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1.
Cell ; 175(1): 239-253.e17, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-30197081

RESUMO

Many disease-causing missense mutations affect intrinsically disordered regions (IDRs) of proteins, but the molecular mechanism of their pathogenicity is enigmatic. Here, we employ a peptide-based proteomic screen to investigate the impact of mutations in IDRs on protein-protein interactions. We find that mutations in disordered cytosolic regions of three transmembrane proteins (GLUT1, ITPR1, and CACNA1H) lead to an increased clathrin binding. All three mutations create dileucine motifs known to mediate clathrin-dependent trafficking. Follow-up experiments on GLUT1 (SLC2A1), the glucose transporter causative of GLUT1 deficiency syndrome, revealed that the mutated protein mislocalizes to intracellular compartments. Mutant GLUT1 interacts with adaptor proteins (APs) in vitro, and knocking down AP-2 reverts the cellular mislocalization and restores glucose transport. A systematic analysis of other known disease-causing variants revealed a significant and specific overrepresentation of gained dileucine motifs in structurally disordered cytosolic domains of transmembrane proteins. Thus, several mutations in disordered regions appear to cause "dileucineopathies."


Assuntos
Transportador de Glucose Tipo 1/fisiologia , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/fisiologia , Motivos de Aminoácidos/genética , Sequência de Aminoácidos , Animais , Sítios de Ligação , Canais de Cálcio Tipo T/genética , Canais de Cálcio Tipo T/fisiologia , Erros Inatos do Metabolismo dos Carboidratos , Clatrina/metabolismo , Citoplasma/metabolismo , Transportador de Glucose Tipo 1/genética , Transportador de Glucose Tipo 1/metabolismo , Humanos , Receptores de Inositol 1,4,5-Trifosfato/genética , Receptores de Inositol 1,4,5-Trifosfato/fisiologia , Proteínas Intrinsicamente Desordenadas/metabolismo , Leucina/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Transporte de Monossacarídeos/deficiência , Mutação/genética , Peptídeos , Ligação Proteica , Proteômica/métodos
2.
Mol Cell ; 80(6): 940-954.e6, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33202251

RESUMO

Mechanisms that control mobilization of cytosolic calcium [Ca2+]i are key for regulation of numerous eukaryotic cell functions. One such paradigmatic mechanism involves activation of phospholipase Cß (PLCß) enzymes by G protein ßγ subunits from activated Gαi-Gßγ heterotrimers. Here, we report identification of a master switch to enable this control for PLCß enzymes in living cells. We find that the Gαi-Gßγ-PLCß-Ca2+ signaling module is entirely dependent on the presence of active Gαq. If Gαq is pharmacologically inhibited or genetically ablated, Gßγ can bind to PLCß but does not elicit Ca2+ signals. Removal of an auto-inhibitory linker that occludes the active site of the enzyme is required and sufficient to empower "stand-alone control" of PLCß by Gßγ. This dependence of Gi-Gßγ-Ca2+ on Gαq places an entire signaling branch of G-protein-coupled receptors (GPCRs) under hierarchical control of Gq and changes our understanding of how Gi-GPCRs trigger [Ca2+]i via PLCß enzymes.


Assuntos
Subunidades alfa de Proteínas de Ligação ao GTP/genética , Subunidades beta da Proteína de Ligação ao GTP/genética , Subunidades gama da Proteína de Ligação ao GTP/genética , Proteínas Heterotriméricas de Ligação ao GTP/genética , Fosfolipase C beta/genética , Cálcio/metabolismo , Sinalização do Cálcio/genética , Citosol/metabolismo , Células HEK293 , Humanos , Ligação Proteica/genética , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais/genética
3.
Bioinformatics ; 40(5)2024 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-38460192

RESUMO

MOTIVATION: The molecular identity of a cell results from a complex interplay between heterogeneous molecular layers. Recent advances in single-cell sequencing technologies have opened the possibility to measure such molecular layers of regulation. RESULTS: Here, we present HuMMuS, a new method for inferring regulatory mechanisms from single-cell multi-omics data. Differently from the state-of-the-art, HuMMuS captures cooperation between biological macromolecules and can easily include additional layers of molecular regulation. We benchmarked HuMMuS with respect to the state-of-the-art on both paired and unpaired multi-omics datasets. Our results proved the improvements provided by HuMMuS in terms of transcription factor (TF) targets, TF binding motifs and regulatory regions prediction. Finally, once applied to snmC-seq, scATAC-seq and scRNA-seq data from mouse brain cortex, HuMMuS enabled to accurately cluster scRNA profiles and to identify potential driver TFs. AVAILABILITY AND IMPLEMENTATION: HuMMuS is available at https://github.com/cantinilab/HuMMuS.


Assuntos
Análise de Célula Única , Fatores de Transcrição , Análise de Célula Única/métodos , Camundongos , Animais , Fatores de Transcrição/metabolismo , Software , Biologia Computacional/métodos , Humanos , Multiômica
4.
BMC Public Health ; 24(1): 2317, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39187842

RESUMO

BACKGROUND: Loss to follow-up in long-term epidemiological studies is well-known and often substantial. Consequently, there is a risk of bias to the results. The motivation to take part in an epidemiological study can change over time, but the ways to minimize loss to follow-up are not well studied. The Citizen Science approach offers researchers to engage in direct discussions with study participants and to integrate their opinions and requirements into cohort management. METHODS: Guided group discussions were conducted with study participants from the KORA cohort in the Augsburg Region in Germany, established 40 years ago, as well as a group of independently selected citizens. The aim was to look at the relevant aspects of health studies with a focus on long-term participation. A two-sided questionnaire was developed subsequently in a co-creation process and presented to 500 KORA participants and 2,400 employees of the research facility Helmholtz Munich. RESULTS: The discussions revealed that altruistic motivations, (i.e. supporting research and public health), personal benefits (i.e. a health check-up during a study examination), data protection, and information about research results in layman's terms were crucial to ensure interest and long-term study participation. The results of the questionnaire confirmed these aspects and showed that exclusively digital information channels may be an obstacle for older and less educated people. Thus, paper-based media such as newsletters are still important. CONCLUSIONS: The findings shed light on cohort management and long-term engagement with study participants. A long-term health study needs to benefit public and individual health; the institution needs to be trustworthy; and the results and their impact need to be disseminated in widely understandable terms and by the right means of communication back to the participants.


Assuntos
Ciência do Cidadão , Opinião Pública , Humanos , Alemanha , Masculino , Feminino , Pessoa de Meia-Idade , Inquéritos e Questionários , Idoso , Adulto , Disseminação de Informação/métodos , Estudos Epidemiológicos , Estudos de Coortes , Registros de Saúde Pessoal , Motivação
5.
Int J Mol Sci ; 25(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38891801

RESUMO

The mechanism underlying podocyte dysfunction in minimal change disease (MCD) remains unknown. This study aimed to shed light on the potential pathophysiology of MCD using glomerular proteomic analysis. Shotgun proteomics using label-free quantitative mass spectrometry was performed on formalin-fixed, paraffin-embedded (FFPE) renal biopsies from two groups of samples: control (CTR) and MCD. Glomeruli were excised from FFPE renal biopsies using laser capture microdissection (LCM), and a single-pot solid-phase-enhanced sample preparation (SP3) digestion method was used to improve yield and protein identifications. Principal component analysis (PCA) revealed a distinct separation between the CTR and MCD groups. Forty-eight proteins with different abundance between the two groups (p-value ≤ 0.05 and |FC| ≥ 1.5) were identified. These may represent differences in podocyte structure, as well as changes in endothelial or mesangial cells and extracellular matrix, and some were indeed found in several of these structures. However, most differentially expressed proteins were linked to the podocyte cytoskeleton and its dynamics. Some of these proteins are known to be involved in focal adhesion (NID1 and ITGA3) or slit diaphragm signaling (ANXA2, TJP1 and MYO1C), while others are structural components of the actin and microtubule cytoskeleton of podocytes (ACTR3 and NES). This study suggests the potential of mass spectrometry-based shotgun proteomic analysis with LCM glomeruli to yield valuable insights into the pathogenesis of podocytopathies like MCD. The most significantly dysregulated proteins in MCD could be attributable to cytoskeleton dysfunction or may be a compensatory response to cytoskeleton malfunction caused by various triggers.


Assuntos
Glomérulos Renais , Nefrose Lipoide , Podócitos , Proteômica , Humanos , Nefrose Lipoide/metabolismo , Nefrose Lipoide/patologia , Proteômica/métodos , Podócitos/metabolismo , Podócitos/patologia , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Masculino , Feminino , Adulto , Proteoma/metabolismo , Proteoma/análise , Microdissecção e Captura a Laser , Pessoa de Meia-Idade
6.
Br J Clin Pharmacol ; 89(2): 602-616, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36331350

RESUMO

AIM: Previous studies on the association between proton pump inhibitor (PPI) intake and the increased risk of dementia has shown discrepancies in their conclusions. We aimed to provide updated evidence based on extensive bias assessments and quantitative sensitivity analyses. METHODS: We searched the databases PubMed, EMBASE, SCOPUS, CENTRAL and clinicaltrials.gov for prospective studies that examined an association between PPI use and dementia, up to February 2022. Each study was assessed using the Cochrane risk of bias assessment tools for non-randomized studies of interventions (ROBINS-I) or randomized trials (RoB2). Pooled risk ratios (RRs) and 95% prediction intervals were computed using random-effects models. Sensitivity analyses were adjusted for small-study bias. RESULTS: We included nine observational studies with 204 108 dementia cases in the primary analysis on the association between PPI use vs. non-use and dementia, and the RR was 1.16 (95% CI = 1.00; 1.35). After adjusting for small-study bias by Copas selection model and Rücker's shrinkage procedure, the RR was 1.16 (1.02; 1.32) and 1.15 (1.13; 1.17), respectively. A subgroup analysis of PPI use vs. non-use regarding Alzheimer's disease risk yielded an RR of 1.15 (0.89; 1.50). The secondary analysis on the risk of dementia by use of PPI vs. histamine-2 receptor antagonist showed an RR of 1.03 (0.66; 1.62). CONCLUSION: This meta-analysis provided no clear evidence for an association between PPI intake and the risk of dementia. Due to discrepancies in sensitivity analyses, however, some risk of dementia by PPI use cannot be ruled out. Since an unequivocal conclusion is still pending, further research is warranted.


Assuntos
Demência , Inibidores da Bomba de Prótons , Humanos , Inibidores da Bomba de Prótons/efeitos adversos , Estudos Prospectivos , Viés , Antagonistas dos Receptores H2 da Histamina/efeitos adversos , Demência/induzido quimicamente , Demência/epidemiologia
7.
J Am Soc Nephrol ; 33(4): 732-745, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35149593

RESUMO

BACKGROUND: The endocytic reabsorption of proteins in the proximal tubule requires a complex machinery and defects can lead to tubular proteinuria. The precise mechanisms of endocytosis and processing of receptors and cargo are incompletely understood. EHD1 belongs to a family of proteins presumably involved in the scission of intracellular vesicles and in ciliogenesis. However, the relevance of EHD1 in human tissues, in particular in the kidney, was unknown. METHODS: Genetic techniques were used in patients with tubular proteinuria and deafness to identify the disease-causing gene. Diagnostic and functional studies were performed in patients and disease models to investigate the pathophysiology. RESULTS: We identified six individuals (5-33 years) with proteinuria and a high-frequency hearing deficit associated with the homozygous missense variant c.1192C>T (p.R398W) in EHD1. Proteinuria (0.7-2.1 g/d) consisted predominantly of low molecular weight proteins, reflecting impaired renal proximal tubular endocytosis of filtered proteins. Ehd1 knockout and Ehd1R398W/R398W knockin mice also showed a high-frequency hearing deficit and impaired receptor-mediated endocytosis in proximal tubules, and a zebrafish model showed impaired ability to reabsorb low molecular weight dextran. Interestingly, ciliogenesis appeared unaffected in patients and mouse models. In silico structural analysis predicted a destabilizing effect of the R398W variant and possible inference with nucleotide binding leading to impaired EHD1 oligomerization and membrane remodeling ability. CONCLUSIONS: A homozygous missense variant of EHD1 causes a previously unrecognized autosomal recessive disorder characterized by sensorineural deafness and tubular proteinuria. Recessive EHD1 variants should be considered in individuals with hearing impairment, especially if tubular proteinuria is noted.


Assuntos
Surdez , Peixe-Zebra , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Surdez/genética , Endocitose , Humanos , Túbulos Renais Proximais/metabolismo , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Camundongos , Mutação , Proteinúria/metabolismo , Proteínas de Transporte Vesicular/genética , Adulto Jovem , Peixe-Zebra/metabolismo
8.
Eur J Neurol ; 29(5): 1335-1343, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35170158

RESUMO

BACKGROUND AND PURPOSE: Understanding the adverse effects of proton pump inhibitors (PPIs) is important due to their widespread use, but the available evidence for an increased dementia risk amongst patients taking PPIs is inconclusive. The present study aimed to estimate the causal effect of PPIs on the risk of dementia by target trial emulation and time-varying exposure modeling. METHODS: Using claims data of 2,698,176 insured people of a large German statutory health insurer, a target trial was conceptualized in which individuals aged 40 years and older were classified as PPI initiators or non-initiators between 2008 and 2018, and were followed until diagnosis of dementia, death, loss to follow-up or end of study. Incidence of dementia (International Classification of Diseases 10 codes F00, F01, F03, F05.1, G30, G31.0, G31.1, G31.9 and F02.8+G31.82) was defined applying a 1-year lag window. Weighted Cox models were used to estimate the effect of PPI initiation versus non-initiation on dementia risk and weighted pooled logistic regression was used to estimate the effect of time-varying use versus non-use. RESULTS: In all, 29,746 PPI initiators (4.4%) and 26,830 non-initiators (1.3%) were diagnosed with dementia. Comparing PPI initiation with no initiation, the hazard ratio for dementia was 1.54 (95% confidence interval 1.51-1.58). The hazard ratio for time-dependent PPI use versus non-use was 1.56 (95% confidence interval 1.50-1.63). Differentiated subtypes, including unspecified dementia, Alzheimer's disease and vascular dementia, showed increased risk by PPI initiation and time-varying PPI use. CONCLUSIONS: This study suggests that PPI initiation and time-varying PPI use may increase overall dementia risk.


Assuntos
Doença de Alzheimer , Demência , Adulto , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/epidemiologia , Demência/induzido quimicamente , Demência/diagnóstico , Demência/epidemiologia , Humanos , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Inibidores da Bomba de Prótons/efeitos adversos , Fatores de Risco
9.
Eur J Clin Pharmacol ; 78(4): 657-667, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34877614

RESUMO

PURPOSE: The German annual drug prescription-report has indicated overuse of proton pump inhibitors (PPIs) for many years; however, little was known about the characteristics of people using PPIs. This study aimed to provide comprehensive utilization data and describe frequencies of potential on- and off-label PPI-indications in Bavaria, Germany. METHODS: Claims data of statutorily insured people from 2010 to 2018 were used. Defined daily doses (DDDs) of PPIs by type of drug, prevalence of PPI-use and DDDs prescribed per 1000 insured people/day were analyzed. For 2018, proportions of users and DDDs per 1000 insured people were calculated by age and sex. To elucidate changes in prescribing practices due to a suspected drug-drug interaction, we examined co-prescribing of clopidogrel and PPIs between 2010 and 2018. For PPI new users, sums of DDDs and frequencies of potential indications were examined. RESULTS: PPI prescribing increased linearly from 2010 to 2016 and gradually decreased from 2016 to 2018. In 2018, 14.7% of women and 12.2% of men received at least one prescription, and 64.8 DDDs (WHO-def.) per 1000 insured people/day were prescribed. Overall, omeprazole use decreased over the observation period and was steadily replaced by pantoprazole, especially when co-prescibed with clopidogrel. An on-label PPI-indication was not reported at first intake in 52.0% of new users. CONCLUSIONS: The utilization of prescribed PPIs has decreased since 2016. However, a large proportion of new PPI-users had no documentation of a potential indication, and the sums of DDDs prescribed often seemed not to comply with guidelines.


Assuntos
Uso de Medicamentos , Inibidores da Bomba de Prótons , Prescrições de Medicamentos , Feminino , Humanos , Masculino , Omeprazol/uso terapêutico , Padrões de Prática Médica , Inibidores da Bomba de Prótons/uso terapêutico , Organização Mundial da Saúde
10.
Blood Purif ; 51(9): 764-771, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34794141

RESUMO

BACKGROUND: Arteriovenous fistula (AVF) failure due to thrombosis is a major cause of morbidity in patients undergoing regular hemodialysis (HD). Advanced glycation end products (AGEs) and their receptor (RAGE) might contribute to inflammation, neointimal hyperplasia, and thrombosis. RAGE has a C-truncated secretory receptor form, called soluble RAGE (sRAGE). In this study, we aimed to evaluate the association of serum sRAGE with AVF failure due to thrombosis in HD patients. METHODS: Eighty-eight prevalent HD patients with functional AVF were included in the study. The presence of stenosis, clinical and laboratory data, and serum sRAGE was evaluated at inclusion. sRAGE concentration was measured by a competitive enzyme-linked immunosorbent assay, and stenosis was detected by ultrasound. Patients were prospectively followed up for 36 months. During this period, AVF failure (defined as the absence of blast or palpable thrill and impossible cannulation with 2 needles because of complete thrombosis) was noted and thrombosis was certified by ultrasound examination. RESULTS: During follow-up, 16 (18.18%) patients lost their vascular access due to thrombosis. In multivariate Cox regression analysis, sRAGE was a significant predictor of vascular access thrombosis (hazard ratio = 1.15, 95% confidence interval: 1.03-1.25, p = 0.012). Kaplan-Meier analysis showed a significantly lower AVF patency time in patients with sRAGE >16.78 ng/mL than those with sRAGE <16.78 ng/mL (p = 0.02). In the subgroup of patients with stenosis at baseline, sRAGE, serum albumin, obesity, and ischemic heart disease were associated with thrombosis. CONCLUSION: In our study, baseline, systemic sRAGE is associated with the occurrence of thrombosis of AVF, and this marker has a significant impact on AVF survival.


Assuntos
Fístula Arteriovenosa , Produtos Finais de Glicação Avançada , Biomarcadores , Constrição Patológica , Humanos , Receptor para Produtos Finais de Glicação Avançada , Diálise Renal/efeitos adversos
11.
Eur J Clin Pharmacol ; 77(7): 1039-1048, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33442768

RESUMO

PURPOSE: Due to conflicting scientific evidence for an increased risk of dementia by intake of proton pump inhibitors (PPIs), this study investigates associations between PPI use and brain volumes, estimated brain age, and cognitive function in the general population. METHODS: Two surveys of the population-based Study of Health in Pomerania (SHIP) conducted in Northeast Germany were used. In total, 2653 participants underwent brain magnetic resonance imaging (MRI) and were included in the primary analysis. They were divided into two groups according to their PPI intake and compared with regard to their brain volumes (gray matter, white matter, total brain, and hippocampus) and estimated brain age. Multiple regression was used to adjust for confounding factors. Cognitive function was evaluated by the Verbal Learning and Memory Test (VLMT) and the Nuremberg Age Inventory (NAI) and put in relation to PPI use. RESULTS: No association was found between PPI use and brain volumes or the estimated brain age. The VLMT score was 1.11 lower (95% confidence interval: - 2.06 to - 0.16) in immediate recall, and 0.72 lower (95% CI: - 1.22 to - 0.22) in delayed recall in PPI users than in non-users. PPI use was unrelated to the NAI score. CONCLUSIONS: The present study does not support a relationship between PPI use and brain aging.


Assuntos
Envelhecimento/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Cognição/efeitos dos fármacos , Inibidores da Bomba de Prótons/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Bomba de Prótons/efeitos adversos , Adulto Jovem
12.
Kidney Int ; 98(1): 159-167, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32471643

RESUMO

Donnai-Barrow syndrome (DBS) is an autosomal-recessive disorder characterized by multiple pathologies including malformation of forebrain and eyes, as well as resorption defects of the kidney proximal tubule. The underlying cause of DBS are mutations in LRP2, encoding the multifunctional endocytic receptor megalin. Here, we identified a unique missense mutation R3192Q of LRP2 in an affected family that may provide novel insights into the molecular causes of receptor dysfunction in the kidney proximal tubule and other tissues affected in DBS. Using patient-derived induced pluripotent stem cell lines we generated neuroepithelial and kidney cell types as models of the disease. Using these cell models, we documented the inability of megalin R3192Q to properly discharge ligand and ligand-induced receptor decay in lysosomes. Thus, mutant receptors are aberrantly targeted to lysosomes for catabolism, essentially depleting megalin in the presence of ligand in this affected family.


Assuntos
Células-Tronco Pluripotentes Induzidas , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Agenesia do Corpo Caloso , Endocitose , Perda Auditiva Neurossensorial , Hérnias Diafragmáticas Congênitas , Humanos , Túbulos Renais Proximais , Ligantes , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Miopia , Proteinúria , Erros Inatos do Transporte Tubular Renal
13.
BMC Public Health ; 20(1): 1901, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-33302924

RESUMO

BACKGROUND: Current evidence suggests that the information needs of people with diabetes mellitus differ across patient groups. With a view to being able to provide individualized information, this study aims to identify (i) the diabetes-related information needs of people with diabetes mellitus; (ii) different subgroups of people with specific information needs; and (iii) associated characteristics of the identified subgroups, such as sociodemographic characteristics, diabetes-related comorbidities, and well-being. METHODS: This cross-sectional study was based on data from 837 respondents with diabetes mellitus who participated in the population-based KORA (Cooperative Health Research in the Augsburg Region) Health Survey 2016 in Southern Germany (KORA GEFU 4 study) (45.6% female, mean age 71.1 years, 92.8% Type 2 diabetes). Diabetes-related information needs were assessed with a questionnaire asking about patients' information needs concerning 11 diabetes-related topics, e.g. 'long-term complications' and 'treatment/therapy'. Subgroups of people with different information needs and associated characteristics were identified using latent class analysis. RESULTS: We identified the following four classes of people with different information needs: 'high needs on all topics', 'low needs on all topics', 'moderate needs with a focus on complications and diabetes in everyday life', and 'advanced needs with a focus on social and legal aspects and diabetes research'. The classes differed significantly in age, years of education, type of diabetes, diabetes duration, diabetes-related comorbidities, smoking behaviour, diabetes education, current level of information, and time preference. CONCLUSIONS: Knowledge about different patient subgroups can be useful for tailored information campaigns or physician-patient interactions. Further research is needed to analyse health care needs in these groups, changes in information needs over the course of the disease, and prospective health outcomes.


Assuntos
Diabetes Mellitus Tipo 2 , Idoso , Estudos Transversais , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Alemanha/epidemiologia , Humanos , Análise de Classes Latentes , Masculino , Estudos Prospectivos
14.
J Fish Biol ; 96(4): 905-912, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32039478

RESUMO

The European river lamprey Lampetra fluviatilis and the European brook lamprey Lampetra planeri (Block 1784) are classified as a paired species, characterized by notably different life histories but morphological similarities. Previous work has further shown limited genetic differentiation between these two species at the mitochondrial DNA level. Here, we expand on this previous work, which focused on lamprey species from the Iberian Peninsula in the south and mainland Europe in the north, by sequencing three mitochondrial marker regions of Lampetra individuals from five river systems in Ireland and five in southern Italy. Our results corroborate the previously identified pattern of genetic diversity for the species pair. We also show significant genetic differentiation between Irish and mainland European lamprey populations, suggesting another ichthyogeographic district distinct from those previously defined. Finally, our results stress the importance of southern Italian L. planeri populations, which maintain several private alleles and notable genetic diversity.


Assuntos
DNA Mitocondrial/genética , Lampreias/classificação , Lampreias/genética , Animais , Europa (Continente) , Genética Populacional , Filogeografia , Rios
15.
Kidney Int ; 96(2): 327-341, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31101366

RESUMO

To elucidate the physiologic function of renal globotriaosylceramide (Gb3/CD77), which up-to-date has been associated exclusively with Shiga toxin binding, we have analyzed renal function in Gb3-deficient mice. Gb3 synthase KO (Gb3S-/-) mice displayed an increased renal albumin and low molecular weight protein excretion compared to WT. Gb3 localized at the brush border and within vesicular structures in WT proximal tubules and has now been shown to be closely associated with the receptor complex megalin/cubilin and with albumin uptake. In two clinically relevant mouse models of acute kidney injury caused by myoglobin as seen in rhabdomyolysis and the aminoglycoside gentamicin, Gb3S-/- mice showed a preserved renal function and morphology, compared to WT. Pharmacologic inhibition of glucosylceramide-based glycosphingolipids, including Gb3, in WT mice corroborated the results of genetically Gb3-deficient mice. In conclusion, our data significantly advance the current knowledge on the physiologic and pathophysiologic role of Gb3 in proximal tubules, showing an involvement in the reabsorption of filtered albumin, myoglobin and the aminoglycoside gentamicin.


Assuntos
Injúria Renal Aguda/tratamento farmacológico , Albuminas/metabolismo , Dioxanos/farmacologia , Galactosiltransferases/antagonistas & inibidores , Pirrolidinas/farmacologia , Reabsorção Renal/efeitos dos fármacos , Triexosilceramidas/metabolismo , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/patologia , Animais , Dioxanos/uso terapêutico , Modelos Animais de Doenças , Galactosiltransferases/genética , Galactosiltransferases/metabolismo , Gentamicinas/metabolismo , Gentamicinas/toxicidade , Humanos , Microscopia Intravital , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/patologia , Túbulos Renais Proximais/ultraestrutura , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , Camundongos , Camundongos Knockout , Microscopia Eletrônica , Microscopia de Fluorescência por Excitação Multifotônica , Microvilosidades/efeitos dos fármacos , Microvilosidades/metabolismo , Mioglobina/metabolismo , Mioglobina/toxicidade , Pirrolidinas/uso terapêutico , Receptores de Superfície Celular/metabolismo , Eliminação Renal/efeitos dos fármacos
16.
Hum Brain Mapp ; 40(5): 1554-1570, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30430687

RESUMO

Activation of parietal cortex structures like the precuneus is commonly observed during explicit memory retrieval, but the role of parietal cortices in encoding has only recently been appreciated and is still poorly understood. Considering the importance of the precuneus in human visual attention and imagery, we aimed to assess a potential role for the precuneus in the encoding of visuospatial representations into long-term memory. We therefore investigated the acquisition of constant versus repeatedly shuffled configurations of icons on background images over five subsequent days in 32 young, healthy volunteers. Functional magnetic resonance imaging was conducted on Days 1, 2, and 5, and persistent memory traces were assessed by a delayed memory test after another 5 days. Constant compared to shuffled configurations were associated with significant improvement of position recognition from Day 1 to 5 and better delayed memory performance. Bilateral dorsal precuneus activations separated constant from shuffled configurations from Day 2 onward, and coactivation of the precuneus and hippocampus dissociated recognized and forgotten configurations, irrespective of condition. Furthermore, learning of constant configurations elicited increased functional coupling of the precuneus with dorsal and ventral visual stream structures. Our results identify the precuneus as a key brain structure in the acquisition of detailed visuospatial information by orchestrating a parieto-occipito-temporal network.


Assuntos
Aprendizagem por Associação/fisiologia , Memória/fisiologia , Lobo Parietal/fisiologia , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto , Mapeamento Encefálico , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/fisiologia , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Lobo Parietal/diagnóstico por imagem , Estimulação Luminosa , Desempenho Psicomotor , Adulto Jovem
17.
J Am Soc Nephrol ; 29(5): 1383-1396, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29444905

RESUMO

BACKGROUND: The kidney is considered to be a structurally stable organ with limited baseline cellular turnover. Nevertheless, single cells must be constantly replaced to conserve the functional integrity of the organ. PDGF chain B (PDGF-BB) signaling through fibroblast PDGF receptor-ß (PDGFRß) contributes to interstitial-epithelial cell communication and facilitates regenerative functions in several organs. However, the potential role of interstitial cells in renal tubular regeneration has not been examined. METHODS: In mice with fluorescent protein expression in renal tubular cells and PDGFRß-positive interstitial cells, we ablated single tubular cells by high laser exposure. We then used serial intravital multiphoton microscopy with subsequent three-dimensional reconstruction and ex vivo histology to evaluate the cellular and molecular processes involved in tubular regeneration. RESULTS: Single-tubular cell ablation caused the migration and division of dedifferentiated tubular epithelial cells that preceded tubular regeneration. Moreover, tubular cell ablation caused immediate calcium responses in adjacent PDGFRß-positive interstitial cells and the rapid migration thereof toward the injury. These PDGFRß-positive cells enclosed the injured epithelium before the onset of tubular cell dedifferentiation, and the later withdrawal of these PDGFRß-positive cells correlated with signs of tubular cell redifferentiation. Intraperitoneal administration of trapidil to block PDGFRß impeded PDGFRß-positive cell migration to the tubular injury site and compromised the recovery of tubular function. CONCLUSIONS: Ablated tubular cells are exclusively replaced by resident tubular cell proliferation in a process dependent on PDGFRß-mediated communication between the renal interstitium and the tubular system.


Assuntos
Desdiferenciação Celular , Células Epiteliais/fisiologia , Túbulos Renais Proximais/fisiologia , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Regeneração , Urotélio/fisiologia , Animais , Cálcio/metabolismo , Comunicação Celular , Movimento Celular/efeitos dos fármacos , Feminino , Microscopia Intravital , Rim/citologia , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/lesões , Linfocinas/metabolismo , Masculino , Camundongos , Inibidores de Fosfodiesterase/farmacologia , Fator de Crescimento Derivado de Plaquetas/metabolismo , Recuperação de Função Fisiológica , Trapidil/farmacologia , Urotélio/lesões
18.
BMC Genomics ; 19(1): 12, 2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29298680

RESUMO

BACKGROUND: The unisexual Amazon molly (Poecilia formosa) originated from a hybridization between two sexual species, the sailfin molly (Poecilia latipinna) and the Atlantic molly (Poecilia mexicana). The Amazon molly reproduces clonally via sperm-dependent parthenogenesis (gynogenesis), in which the sperm of closely related species triggers embryogenesis of the apomictic oocytes, but typically does not contribute genetic material to the next generation. We compare for the first time the gonadal transcriptome of the Amazon molly to those of both ancestral species, P. mexicana and P. latipinna. RESULTS: We sequenced the gonadal transcriptomes of the P. formosa and its parental species P. mexicana and P. latipinna using Illumina RNA-sequencing techniques (paired-end, 100 bp). De novo assembly of about 50 million raw read pairs for each species was performed using Trinity, yielding 106,922 transcripts for P. formosa, 115,175 for P. latipinna, and 133,025 for P. mexicana after eliminating contaminations. On the basis of sequence similarity comparisons to other teleost species and the UniProt databases, functional annotation, and differential expression analysis, we demonstrate the similarity of the transcriptomes among the three species. More than 40% of the transcripts for each species were functionally annotated and about 70% were assigned to orthologous genes of a closely related species. Differential expression analysis between the sexual and unisexual species uncovered 2035 up-regulated and 564 down-regulated genes in P. formosa. This was exemplary validated for six genes by qRT-PCR. CONCLUSIONS: We identified more than 130 genes related to meiosis and reproduction within the apomictically reproducing P. formosa. Overall expression of these genes seems to be down-regulated in the P. formosa transcriptome compared to both ancestral species (i.e., 106 genes down-regulated, 29 up-regulated). A further 35 meiosis and reproduction related genes were not found in the P. formosa transcriptome, but were only expressed in the sexual species. Our data support the hypothesis of general down-regulation of meiosis-related genes in the apomictic Amazon molly. Furthermore, the obtained dataset and identified gene catalog will serve as a resource for future research on the molecular mechanisms behind the reproductive mode of this unisexual species.


Assuntos
Gônadas/metabolismo , Poecilia/genética , Transcriptoma , Animais , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Meiose/genética , Partenogênese/genética , Poecilia/metabolismo , Análise de Sequência de RNA
19.
Pharmacoepidemiol Drug Saf ; 27(7): 806-814, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29797371

RESUMO

PURPOSE: We evaluated the pharmacological treatment of distal sensorimotor polyneuropathy (DSPN) among older subjects from the general population. METHODS: The study included subjects aged 61 to 82 years from the KORA F4 survey (2006-2008). DSPN was defined as the presence of bilaterally impaired foot-vibration perception and/or bilaterally impaired foot-pressure sensation. Pain intensity was assessed with the painDETECT questionnaire. RESULTS: From the included 1076 older persons, 172 (16%) persons reported pain in the lower extremities and DSPN was present in 150 (14%) subjects. Forty-eight people with pain in the lower extremities reported DSPN. Only 38% of the subjects with DSPN reporting an average pain level of ≥4 during the past 4 weeks received medical treatment, predominantly nonsteroidal anti-inflammatory drugs (NSAIDs 20% and opioids 12%). The medication of choice for neuropathic pain, antidepressants, anticonvulsants, and opioids was relatively being underused. However, opioids and neuropathy preparations were prescribed preferably for subjects with painful DSPN. CONCLUSIONS: In the older general population, only a small proportion of subjects with painful DSPN receive analgesic pharmacotherapy. Although not recommended by guidelines for the treatment of neuropathic pain, NSAIDs were the most frequently used class of analgesic drugs.


Assuntos
Analgésicos/uso terapêutico , Anticonvulsivantes/uso terapêutico , Antidepressivos/uso terapêutico , Neuropatias Diabéticas/tratamento farmacológico , Neuralgia/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Analgésicos/administração & dosagem , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/uso terapêutico , Anticonvulsivantes/administração & dosagem , Antidepressivos/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
J Math Biol ; 77(3): 527-544, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29248985

RESUMO

Phylogenetic inference aims to reconstruct the evolutionary relationships of different species based on genetic (or other) data. Discrete characters are a particular type of data, which contain information on how the species should be grouped together. However, it has long been known that some characters contain more information than others. For instance, a character that assigns the same state to each species groups all of them together and so provides no insight into the relationships of the species considered. At the other extreme, a character that assigns a different state to each species also conveys no phylogenetic signal. In this manuscript, we study a natural combinatorial measure of the information content of an individual character and analyse properties of characters that provide the maximum phylogenetic information, particularly, the number of states such a character uses and how the different states have to be distributed among the species or taxa of the phylogenetic tree.


Assuntos
Modelos Biológicos , Filogenia , Animais , Evolução Biológica , Simulação por Computador , Conceitos Matemáticos , Modelos Genéticos , Especificidade da Espécie
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