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1.
Hum Mol Genet ; 28(5): 751-763, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30388220

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) is among the most common monogenic disorders mainly associated with PKD1/PC1 mutations. We show herein that renal regulation in Pc1 dosage-reduced and -increased mouse models converge toward stimulation of c-Myc expression along with ß-catenin, delineating c-Myc as a key Pkd1 node in cystogenesis. Enhanced renal c-Myc-induced ADPKD in SBM transgenic mice lead conversely to striking upregulation of Pkd1/Pc1 expression and ß-catenin activation, lending credence for reciprocal crosstalk between c-Myc and Pc1. In adult SBM kidneys, c-Myc is strongly enriched on Pkd1 promoter with RNA pol II, consistent with Pkd1 upregulation during cystogenesis. Similar c-Myc direct binding at birth uncovers an equivalent role on Pkd1 regulation during renal developmental program. Concurrent with enriched c-Myc binding, recruitment of active chromatin modifying co-factors by c-Myc at the Pkd1 regulatory region probably opens chromatin to stimulate transcription. A similar transcriptional activation by c-Myc is also likely operant on endogenous human PKD1 gene from our transactivation analysis in response to human c-MYC upregulation. Genetic ablation of c-Myc in Pc1-reduced and -increased mouse models significantly attenuates cyst growth, proliferation and PKD progression. Our study determined a dual role for c-Myc, as a major contributor in Pc1-induced cystogenesis and in a feed-forward regulatory Pkd1-c-Myc loop mechanism that may also prevail in human ADPKD.


Assuntos
Regulação da Expressão Gênica , Predisposição Genética para Doença , Proteínas Proto-Oncogênicas c-myc/metabolismo , Canais de Cátion TRPP/genética , Animais , Sequência de Bases , Sítios de Ligação , Biomarcadores , Linhagem Celular , Modelos Animais de Doenças , Progressão da Doença , Dosagem de Genes , Estudos de Associação Genética , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Modelos Biológicos , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/metabolismo , Rim Policístico Autossômico Dominante/patologia , Ligação Proteica , Transdução de Sinais , Canais de Cátion TRPP/metabolismo , Transcrição Gênica
2.
Blood Cells Mol Dis ; 92: 102619, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34768199

RESUMO

The molecular identity of Psickle, the deoxygenation-activated cation conductance of the human sickle erythrocyte, remains unknown. We observed in human sickle red cells that inhibitors of TRPA1 and TRPV1 inhibited Psickle, whereas a TRPV1 agonist activated a Psickle-like cation current. These observations prompted us to test the roles of TRPV1 and TRPA1 in Psickle in red cells of the SAD mouse model of sickle cell disease. We generated SAD mice genetically deficient in either TRPV1 or TRPA1. SAD;Trpv1-/- and SAD;Trpa1-/- mice were indistinguishable in appearance, hematological indices, and osmotic fragility from SAD mice. We found that deoxygenation-activated cation currents remained robust in SAD;Trpa1-/- and SAD;Trpv1-/- mice. In addition, 45Ca2+ influx into SAD mouse red cells during prolonged deoxygenation was not reduced in red cells from SAD;Trpa1-/- and SAD;Trpv1-/- mice. We conclude that the nonspecific cation channels TRPA1 and TRPV1 are not required for deoxygenation to stimulate Psickle-like activity in red cells of the SAD mouse model of sickle cell disease. (159).


Assuntos
Anemia Falciforme/metabolismo , Eritrócitos/patologia , Canal de Cátion TRPA1/metabolismo , Canais de Cátion TRPV/metabolismo , Anemia Falciforme/genética , Anemia Falciforme/patologia , Animais , Cátions/metabolismo , Modelos Animais de Doenças , Eritrócitos/metabolismo , Deleção de Genes , Humanos , Camundongos , Camundongos Knockout , Canal de Cátion TRPA1/genética , Canais de Cátion TRPV/genética
3.
PLoS Genet ; 13(4): e1006694, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28406902

RESUMO

Progressive cystic kidney degeneration underlies diverse renal diseases, including the most common cause of kidney failure, autosomal dominant Polycystic Kidney Disease (PKD). Genetic analyses of patients and animal models have identified several key drivers of this disease. The precise molecular and cellular changes underlying cystogenesis remain, however, elusive. Drosophila mutants lacking the translational regulator Bicaudal C (BicC, the fly ortholog of vertebrate BICC1 implicated in renal cystogenesis) exhibited progressive cystic degeneration of the renal tubules (so called "Malpighian" tubules) and reduced renal function. The BicC protein was shown to bind to Drosophila (d-) myc mRNA in tubules. Elevation of d-Myc protein levels was a cause of tubular degeneration in BicC mutants. Activation of the Target of Rapamycin (TOR) kinase pathway, another common feature of PKD, was found in BicC mutant flies. Rapamycin administration substantially reduced the cystic phenotype in flies. We present new mechanistic insight on BicC function and propose that Drosophila may serve as a genetically tractable model for dissecting the evolutionarily-conserved molecular mechanisms of renal cystogenesis.


Assuntos
Proteínas de Drosophila/genética , Doenças Renais Policísticas/etiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas de Ligação a RNA/genética , Animais , Animais Geneticamente Modificados , Cistos , Modelos Animais de Doenças , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Regulação da Expressão Gênica , Túbulos de Malpighi/patologia , Mutação , Doenças Renais Policísticas/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas de Ligação a RNA/metabolismo , Regulação para Cima
4.
BMC Med Inform Decis Mak ; 20(1): 44, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-32111203

RESUMO

BACKGROUND: Laboratory testing occupies a prominent place in health care. Information technology systems have the potential to empower laboratory experts and to enhance the interpretation of test results in order to better support physicians in their quest for better and safer patient care. This study sought to develop a better understanding of which laboratory information exchange (LIE) systems and features specialist physicians are using in hospital settings to consult their patients' laboratory test results, and what benefit they derive from such use. METHODS: As part of a broader research program on the use of health information exchange systems for laboratory medicine in Quebec, Canada, this study was designed as on online survey. Our sample is composed of 566 specialist physicians working in hospital settings, out of the 1512 physicians who responded to the survey (response rate of 17%). Respondents are representative of the targeted population of specialist physicians in terms of gender, age and hospital location. RESULTS: We first observed that 80% of the surveyed physicians used the province-wide interoperable electronic health records (iEHR) system and 93% used a laboratory results viewer (LRV) to consult laboratory test results and most (72%) use both systems to retrieve lab results. Next, our findings reveal important differences in the capabilities available in each type of system and in the use of these capabilities. Third, there are differences in the nature of the perceived benefits obtained from the use of each of these two systems. Last, the extent of use of an LRV is strongly influenced by the IT artefact itself (i.e., the hospital's LRV available capabilities) while the use of the provincial iEHR system is influenced by its organizational context (i.e. the hospital's size and location). CONCLUSIONS: The main contribution of this study lies in its insights into the role played by context in shaping physicians' choices about which laboratory information exchange systems to adopt and which features to use, and the different perceptions they have about benefits arising from such use. One related implication for practice is that success of LIE initiatives should not be solely assessed with basic usage statistics.


Assuntos
Técnicas de Laboratório Clínico , Troca de Informação em Saúde/estatística & dados numéricos , Troca de Informação em Saúde/normas , Médicos/psicologia , Médicos/estatística & dados numéricos , Especialização , Feminino , Hospitais , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Quebeque , Inquéritos e Questionários
5.
Blood Cells Mol Dis ; 79: 102346, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31352162

RESUMO

Excessive red cell dehydration contributes to the pathophysiology of sickle cell disease (SCD). The densest fraction of sickle red cells (with the highest corpuscular hemoglobin concentration) undergoes the most rapid polymerization of deoxy-hemoglobin S, leading to accelerated cell sickling and increased susceptibility to endothelial activation, red cell adhesion, and vaso-occlusion. Increasing red cell volume in order to decrease red cell density can thus serve as an adjunct therapeutic goal in SCD. Regulation of circulating mouse red cell volume and density is mediated largely by the Gardos channel, KCNN4, and the K-Cl cotransporters, KCC3 and KCC1. Whereas inhibition of the Gardos channel in subjects with sickle cell disease increased red cell volume, decreased red cell density, and improved other hematological indices in subjects with SCD, specific KCC inhibitors have not been available for testing. We therefore investigated the effect of genetic inactivation of KCC3 and KCC1 in the SAD mouse model of sickle red cell dehydration, finding decreased red cell density and improved hematological indices. We describe here generation of mice genetically deficient in the three major red cell volume regulatory gene products, KCNN4, KCC3, and KCC1 in C57BL6 non-sickle and SAD sickle backgrounds. We show that combined loss-of-function of all three gene products in SAD mice leads to incrementally increased MCV, decreased CHCM and % hyperchromic cells, decreased red cell density (phthalate method), increased resistance to hypo-osmotic lysis, and increased cell K content. The data show that combined genetic deletion of the Gardos channel and K-Cl cotransporters in a mouse SCD model decreases red cell density and improves several hematological parameters, supporting the strategy of combined pharmacological inhibition of these ion transport pathways in the adjunct treatment of human SCD.


Assuntos
Anemia Falciforme/sangue , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Animais , Tamanho Celular/efeitos dos fármacos , Desidratação/tratamento farmacológico , Modelos Animais de Doenças , Eritrócitos/patologia , Humanos , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/deficiência , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Camundongos , Simportadores/deficiência , Simportadores/genética , Cotransportadores de K e Cl-
6.
Am J Physiol Renal Physiol ; 315(1): F57-F73, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29537311

RESUMO

Following the discovery of (R)-roscovitine's beneficial effects in three polycystic kidney disease (PKD) mouse models, cyclin-dependent kinases (CDKs) inhibitors have been investigated as potential treatments. We have used various affinity chromatography approaches to identify the molecular targets of roscovitine and its more potent analog (S)-CR8 in human and murine polycystic kidneys. These methods revealed casein kinases 1 (CK1) as additional targets of the two drugs. CK1ε expression at the mRNA and protein levels is enhanced in polycystic kidneys of 11 different PKD mouse models as well as in human polycystic kidneys. A shift in the pattern of CK1α isoforms is observed in all PKD mouse models. Furthermore, the catalytic activities of both CK1ε and CK1α are increased in mouse polycystic kidneys. Inhibition of CK1ε and CK1α may thus contribute to the long-lasting attenuating effects of roscovitine and (S)-CR8 on cyst development. CDKs and CK1s may constitute a dual therapeutic target to develop kinase inhibitory PKD drug candidates.


Assuntos
Caseína Quinase 1 épsilon/antagonistas & inibidores , Caseína Quinase Ialfa/antagonistas & inibidores , Rim/efeitos dos fármacos , Doenças Renais Policísticas/prevenção & controle , Inibidores de Proteínas Quinases/farmacologia , Purinas/farmacologia , Piridinas/farmacologia , Roscovitina/farmacologia , Animais , Caseína Quinase 1 épsilon/genética , Caseína Quinase 1 épsilon/metabolismo , Caseína Quinase Ialfa/genética , Caseína Quinase Ialfa/metabolismo , Catálise , Cromatografia de Afinidade/métodos , Modelos Animais de Doenças , Humanos , Rim/enzimologia , Rim/patologia , Camundongos Transgênicos , Doenças Renais Policísticas/enzimologia , Doenças Renais Policísticas/genética , Doenças Renais Policísticas/patologia , Ligação Proteica , Inibidores de Proteínas Quinases/metabolismo , Purinas/metabolismo , Piridinas/metabolismo , Roscovitina/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Hum Mol Genet ; 24(14): 3982-93, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-25877301

RESUMO

In this study, we identified a BET bromodomain (BRD) protein, Brd4, not only as a novel epigenetic regulator of autosomal dominant polycystic kidney disease (ADPKD) but also as a novel client protein of Hsp90. We found that Brd4 was upregulated in Pkd1 mutant mouse renal epithelial cells and tissues. This upregulation of Brd4 appears to result from the chaperone activity of Hsp90 and escape proteasomal degradation. We further identify that Brd4 is an upstream regulator of the expression of c-Myc which has been upregulated in all rodent models of PKD and ADPKD patients with unknown mechanism. Inhibition of Brd4 in Pkd1 mutant renal epithelial cells with JQ1, a selective small-molecular inhibitor of BET BRD protein(s), (1) decreased the levels of c-Myc mRNA and protein; (2) increased the levels of p21 mRNA and protein, which was transcriptionally repressed by c-Myc; (3) decreased the phosphorylation of Rb; and (4) decreased cystic epithelial cell proliferation as shown by inhibition of S-phase entry. Most importantly, treatment with JQ1 strikingly delayed cyst growth and kidney enlargement, and preserved renal function in two early stage genetic mouse strains with Pkd1 mutations. This study not only provides one of the mechanisms of how c-Myc is upregulated in PKD but also suggests that targeting Brd4 with JQ1 may function as a novel epigenetic approach in ADPKD. The unraveled link between Brd4 and Hsp90 in ADPKD may also be a general mechanism for the upregulation of Brd4 in cancer cells and opens up avenues for combination therapies against ADPKD and cancer.


Assuntos
Cistos/terapia , Marcação de Genes/métodos , Proteínas Nucleares/genética , Rim Policístico Autossômico Dominante/terapia , Fatores de Transcrição/genética , Animais , Azepinas/farmacologia , Proteínas de Ciclo Celular , Proliferação de Células , Cistos/genética , Modelos Animais de Doenças , Epigênese Genética , Células Epiteliais/metabolismo , Feminino , Células HEK293 , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Masculino , Camundongos Knockout , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Fosforilação , Rim Policístico Autossômico Dominante/genética , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Triazóis/farmacologia , Regulação para Cima
8.
Blood Cells Mol Dis ; 65: 60-65, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28552477

RESUMO

Deoxy-hemoglobin S polymerization into rigid fibers is the direct cause of the clinical sequelae observed in sickle cell disease (SCD). The rate of polymerization of sickle hemoglobin is determined primarily by intracellular hemoglobin concentration, itself dependent on the amount of sickle hemoglobin and on red blood cell (RBC) volume. Dense, dehydrated RBC (DRBC) are observed in SCD patients, and their number correlates with hemolytic parameters and complications such as renal dysfunction, leg ulcers and priapism. To identify new genes involved in RBC hydration in SCD, we performed the first genome-wide association study for DRBC in 374 sickle cell anemia (HbSS) patients. We did not find genome-wide significant results, indicating that variants that modulate DRBC have modest-to-weak effects. A secondary analysis demonstrated a nominal association (P=0.003) between DRBC in SCD patients and a variant associated with mean corpuscular hemoglobin concentration (MCHC) in non-anemic individuals. This intronic variant controls the expression of ATP2B4, the main calcium pump in erythrocytes. Our study highlights ATP2B4 as a promising target for modulation of RBC hydration in SCD patients.


Assuntos
Anemia Falciforme/sangue , Anemia Falciforme/genética , Eritrócitos/metabolismo , Estudo de Associação Genômica Ampla , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/metabolismo , Adulto , Alelos , Índices de Eritrócitos , Feminino , Variação Genética , Genótipo , Humanos , Masculino , ATPases Transportadoras de Cálcio da Membrana Plasmática/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Adulto Jovem
9.
BMC Med Inform Decis Mak ; 17(1): 46, 2017 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-28427405

RESUMO

BACKGROUND: There has been indisputable growth in adoption of electronic medical record (EMR) systems in the recent years. However, physicians' progress in using these systems has stagnated when measured with maturity scales. While this so-called ceiling effect has been observed and its consequences described in previous studies, there is a paucity of research on the elements that could explain such an outcome. We first suggest that in the context of EMR systems we are in presence of a "tiered ceiling effect" and then we show why such phenomenon occurs. METHODS: We conducted in-depth case studies in three primary care medical practices in Canada where physicians had been using EMR systems for 3 years or more. A total of 37 semi-structured interviews were conducted with key informants: family physicians (about half of the interviews), nurses, secretaries, and administrative managers. Additional information was obtained through notes taken during observations of users interacting with their EMR systems and consultation of relevant documents at each site. We used abductive reasoning to infer explanations of the observed phenomenon by going back and forth between the case data and conceptual insights. RESULTS: Our analysis shows that a ceiling effect has taken place in the three clinics. We identified a set of conditions preventing the users from overcoming the ceiling. In adopting an EMR system, all three clinics essentially sought improved operational efficiency. This had an influence on the criteria used to assess the systems available on the market and eventually led to the adoption of a system that met the specified criteria without being optimal. Later, training sessions focussed on basic functionalities that minimally disturbed physicians' habits while helping their medical practices become more efficient. Satisfied with the outcome of their system use, physicians were likely to ignore more advanced EMR system functionalities. This was because their knowledge about EMR systems came almost exclusively from a single source of information: their EMR system vendors. This knowledge took the form of interpretations of what the innovation was (know-what), with little consideration of the rationales for innovation adoption (know-why) or hands-on strategies for adopting, implementing and assimilating the innovation in the organization (know-how). CONCLUSIONS: This paper provides a holistic view of the technological innovation process in primary care and contends that limited learning, satisficing behaviours and organizational inertia are important factors leading to the ceiling effect frequently experienced in the EMR system assimilation phase.


Assuntos
Difusão de Inovações , Registros Eletrônicos de Saúde/estatística & dados numéricos , Medicina de Família e Comunidade/organização & administração , Sistemas Computadorizados de Registros Médicos/estatística & dados numéricos , Padrões de Prática Médica/organização & administração , Atitude do Pessoal de Saúde , Canadá , Atenção à Saúde/organização & administração , Humanos , Atenção Primária à Saúde/organização & administração
10.
Am J Physiol Renal Physiol ; 311(4): F740-F751, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27488998

RESUMO

Acute kidney injury (AKI) and autosomal dominant polycystic kidney disease (ADPKD) are considered separate entities that both frequently cause renal failure. Since ADPKD appears to depend on a polycystin-1 (Pc1) or Pc2 dosage mechanism, we investigated whether slow progression of cystogenesis in two Pkd1 transgenic mouse models can be accelerated with moderate ischemia-reperfusion injury (IRI). Transient unilateral left ischemic kidneys in both nontransgenic and transgenic mice reproducibly develop tubular dilatations, cysts, and typical PKD cellular defects within 3 mo post-IRI. Similar onset and severity of IRI induced-cystogenesis independently of genotype revealed that IRI is sufficient to promote renal cyst formation; however, this response was not further amplified by the transgene in Pkd1 mouse models. The IRI nontransgenic and transgenic kidneys showed from 16 days post-IRI strikingly increased and sustained Pkd1/Pc1 (>3-fold) and Pc2 (>8-fold) expression that can individually be cystogenic in mice. In parallel, long-term and important stimulation of hypoxia-inducible factor 1α expression was induced as in polycystic kidney disease. While mammalian target of rapamycin signaling is activated, stimulation of the Wnt pathway, with markedly increased active ß-catenin and c-Myc expression in IRI renal epithelium, uncovered a similar regulatory cystogenic response shared by IRI and ADPKD. Our study demonstrates that long-term AKI induces cystogenesis and cross talk with ADPKD Pc1/Pc2 pathogenic signaling.


Assuntos
Injúria Renal Aguda/patologia , Isquemia/patologia , Rim/patologia , Doenças Renais Policísticas/patologia , Canais de Cátion TRPP/metabolismo , Injúria Renal Aguda/metabolismo , Animais , Modelos Animais de Doenças , Isquemia/metabolismo , Rim/irrigação sanguínea , Rim/metabolismo , Camundongos , Camundongos Transgênicos , Doenças Renais Policísticas/metabolismo , Transdução de Sinais/fisiologia , Canais de Cátion TRPP/genética
11.
Telemed J E Health ; 22(3): 246-50, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26252758

RESUMO

BACKGROUND: Telepathology is a fast growing segment of the telemedicine field. As of yet, no prior research has investigated the impacts of large decentralized telepathology projects on patients, clinicians, and healthcare systems. This study aims to fill this gap. We report a benefits evaluation study of a large decentralized telepathology project deployed in Eastern Quebec, Canada whose main objective is to provide continuous coverage of intraoperative consultations in remote hospitals without pathologists on-site. The project involves 18 hospitals, making it one of the largest telepathology networks in the world. MATERIALS AND METHODS: We conducted 43 semistructured interviews with several telepathology users and hospital managers. Archival data on the impacts of the telepathology project (e.g., number of service disruptions, average time between initial diagnosis and surgery) were also extracted and analyzed. RESULTS: Our findings show that no service disruptions were recorded in hospitals without pathologists following the deployment of telepathology. Surgeons noted that the use of intraoperative consultations enabled by telepathology helped avoid second surgeries and improved accessibility to care services. Telepathology was also perceived by our respondents as having positive impacts on the remote hospitals' ability to retain and recruit surgeons. CONCLUSIONS: The observed benefits should not leave the impression that implementing telepathology is a trivial matter. Indeed, many technical, human, and organizational challenges may be encountered. Telepathology can be highly useful in regional hospitals that do not have a pathologist on-site. More research is needed to investigate the challenges and benefits associated with large decentralized telepathology networks.


Assuntos
Redes Comunitárias/organização & administração , Telepatologia/organização & administração , Canadá , Redução de Custos , Atenção à Saúde/organização & administração , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde , Política , Avaliação de Programas e Projetos de Saúde , Quebeque
12.
Hum Mol Genet ; 22(12): 2361-75, 2013 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-23439951

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by slow progression of multiple cysts in both kidneys that lead to renal insufficiency in mid-life or later. ADPKD is associated with mutations mainly in the PKD1 gene (encoding polycystin-1 or PC1) and less frequently in the PKD2 gene (encoding polycystin-2 or PC2). To mimic naturally occurring human PKD1 mutations and gain insight into the PC1 extracellular domain function, four transgenic mouse lines were established with exclusively the extracellular domain of the Pkd1 gene (Pkd1(extra)) under endogenous transcriptional regulation. Expression of the Pkd1(extra) transgene was 2- to 80-fold above endogenous levels. Strikingly, the Pc1(extra) protein was more abundant, proportionally to the endogenous levels. All four transgenic mouse lines consistently displayed progressive renal cystic phenotype. Consequently, these transgenic mice reproducibly developed renal functional alterations similar to human ADPKD with proteinuria, renal insufficiency, anemia and died of renal failure late in life. In precystic kidneys, the Pkd1(extra) transgene modulated Pc2 expression and thereby, uncovered a potential Pc1-mutant/Pc2 pathogenic crosstalk mechanism. Moreover, the pathophysiologic mechanism also implicates c-myc, a major modulator of cystogenesis. Altogether, the novel Pkd1(extra) mouse model is the first Pc1 extracellular mutant that reproduces human ADPKD clinical progression and physiopathology.


Assuntos
Doenças Renais Policísticas/metabolismo , Canais de Cátion TRPP/química , Canais de Cátion TRPP/metabolismo , Animais , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Rim/crescimento & desenvolvimento , Rim/metabolismo , Rim/patologia , Masculino , Camundongos , Camundongos Transgênicos , Mutação , Doenças Renais Policísticas/genética , Doenças Renais Policísticas/patologia , Estrutura Terciária de Proteína , Canais de Cátion TRPP/genética
14.
BMC Med Inform Decis Mak ; 15: 27, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25888991

RESUMO

BACKGROUND: Numerous calls have been made for greater assimilation of information technology in healthcare organizations in general, and in primary care settings in particular. Considering the levels of IT investment and adoption in primary care medical practices, a deeper understanding is needed of the factors leading to greater performance outcomes from EMR systems in primary care. To address this issue, we developed and tested a research model centered on the concept of Extended EMR Use. METHODS: An online survey was conducted of 331 family physicians in Canadian private medical practices to empirically test seven research hypotheses using a component-based structural equation modeling approach. RESULTS: Five hypotheses were partially or fully supported by our data. Family physicians in our sample used 67% of the clinical and 41% of the communicational functionalities available in their EMR systems, compared to 90% of the administrative features. As expected, extended use was associated with significant improvements in perceived performance benefits. Interestingly, the benefits derived from system use were mainly tied to the clinical support provided by an EMR system. The extent to which physicians were using their EMR systems was influenced by two system design characteristics: functional coverage and ease of use. The more functionalities that are available in an EMR system and the easier they are to use, the greater the potential for exploration, assimilation and appropriation by family physicians. CONCLUSIONS: Our study has contributed to the extant literature by proposing a new concept: Extended EMR Use. In terms of its practical implications, our study reveals that family physicians must use as many of the capabilities supported by their EMR system as possible, especially those which support clinical tasks, if they are to maximize its performance benefits. To ensure extended use of their software, vendors must develop EMR systems that satisfy two important design characteristics: functional coverage and system ease of use.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Pesquisa sobre Serviços de Saúde/métodos , Médicos de Família/normas , Prática Privada/normas , Adulto , Medicina de Família e Comunidade/normas , Pesquisas sobre Atenção à Saúde , Humanos , Quebeque
15.
Blood Cells Mol Dis ; 51(1): 9-16, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23481459

RESUMO

The K-Cl cotransporters (KCCs) of mouse erythrocytes exhibit higher basal activity than those of human erythrocytes, but are similarly activated by cell swelling, by hypertonic urea, and by staurosporine. However, the dramatic stimulation of human erythroid KCCs by N-ethylmaleimide (NEM) is obscured in mouse erythrocytes by a prominent NEM-stimulated K(+) efflux that lacks Cl(-)-dependence. The NEM-sensitivity of Cl(-)-independent K(+) efflux of mouse erythrocytes is lower than that of KCC. The genetically engineered absence of the K-Cl cotransporters KCC3 and KCC1 from mouse erythrocytes does not modify Cl(-)-independent K(+) efflux. Mouse erythrocytes genetically devoid of the Gardos channel KCNN4 show increased NEM-sensitivity of both Cl(-)-independent K(+) efflux and K-Cl cotransport. The increased NEM-sensitivity and stimulation magnitude of Cl(-)-independent K(+) efflux in mouse erythrocytes expressing transgenic hypersickling human hemoglobin SAD (HbSAD) are independent of the presence of KCC3 and KCC1, but absence of KCNN4 reduces the stimulatory effect of HbSAD. NEM-stimulated Cl(-)-independent K(+) efflux of mouse red cells is insensitive to ouabain and bumetanide, but partially inhibited by chloroquine, barium, and amiloride. The NEM-stimulated activity is modestly reduced at pH6.0 but not significantly altered at pH8.0, and is abolished at 0°C. Although the molecular identity of this little-studied K(+) efflux pathway of mouse erythrocytes remains unknown, its potential role in the pathophysiology of sickle red cell dehydration will be important for the extrapolation of studies in mouse models of sickle cell disease to our understanding of humans with sickle cell anemia.


Assuntos
Cloretos/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Etilmaleimida/farmacologia , Potássio/metabolismo , Simportadores/agonistas , Simportadores/metabolismo , Amilorida/farmacologia , Animais , Cloroquina/farmacologia , Resistência a Medicamentos/genética , Hemoglobina Falciforme/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Camundongos , Camundongos Knockout , Simportadores/antagonistas & inibidores , Temperatura , Cotransportadores de K e Cl-
16.
Mol Ther Methods Clin Dev ; 29: 366-380, 2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37214311

RESUMO

Autosomal dominant polycystic kidney disease (ADPKD) causes renal cysts and leads to end-stage renal disease in midlife due mainly to PKD1 gene mutations. Virtually no studies have explored gene therapeutic strategies for long-term effective treatment of PKD. Toward this aim, the severely cystic Pkd1-null mouse model was targeted with a series of transgene transfers using genomic Pkd1 under its regulatory elements (Pkd1wt), a kidney-targeted Pkd1 gene (SBPkd1), or Pkd1Minigene. The introduced Pkd1wt gene constructs with ∼8-fold overexpression display similar endogenous cellular profiles and full complementation of Pkd1-/- phenotype and establish the referral Pkd1 genomic length for proper regulation. SBPkd1 transgene transfer expressing 0.6- or 7-fold Pkd1 endogenous levels is sufficient to correct glomerular and proximal tubular cysts and to markedly postpone cysts in other tubular segments as well, showing that the small SB elements appreciably overlap with Pkd1 promoter/5' UTR regulation. Renal-targeted Pkd1Minigene at high copy numbers conveys an expression level similar to that of the endogenous Pkd1 gene, with widespread and homogeneous weak Pkd1 cellular signal, partially rescuing all cystic tubular segments. These transgene transfers determine that Pkd1 intragenic sequences regulate not only expression levels but also spatiotemporal patterns. Importantly, our study demonstrates that Pkd1 re-expression from hybrid therapeutic constructs can ameliorate, with considerably extended lifespan, or eliminate PKD.

17.
Vaccine ; 41(21): 3387-3398, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37105892

RESUMO

BACKGROUND: V114 (15-valent pneumococcal conjugate vaccine [PCV]) contains all serotypes in 13-valent PCV (PCV13) and additional serotypes 22F and 33F. This study evaluated safety and immunogenicity of V114 compared with PCV13 in healthy infants, and concomitant administration with DTPa-HBV-IPV/Hib and rotavirus RV1 vaccines. METHODS: V114 and PCV13 were administered in a 2+1 schedule at 2, 4, and 11-15 months of age. Adverse events (AEs) were collected on Days 1-14 following each vaccination. Serotype-specific anti-pneumococcal immunoglobulin G (IgG) was measured 30 days post-primary series (PPS), immediately prior to a toddler dose, and 30 days post-toddler dose (PTD). Primary objectives included non-inferiority of V114 to PCV13 for 13 shared serotypes and superiority of V114 to PCV13 for the two additional serotypes. RESULTS: 1184 healthy infants 42-90 days of age were randomized 1:1 to V114 (n = 591) or PCV13 (n = 593). Proportions of participants with solicited AEs and serious AEs were comparable between vaccination groups. V114 met pre-specified non-inferiority criteria for all 13 shared serotypes, based on the difference in proportions of participants with serotype-specific IgG concentrations ≥0.35 µg/mL (response rate; lower bound of two-sided 95% confidence interval [CI] >-10.0) and IgG geometric mean concentration (GMC) ratios (lower bound of two-sided 95% CI >0.5), and pre-specified superiority criteria for serotypes 22F and 33F (lower bound of two-sided 95% CI >10.0 for response rates and >2.0 for GMC ratios). Antibody responses to DTPa-HBV-IPV/Hib and RV1 vaccines met pre-specified non-inferiority criteria, based on antigen-specific response rates to DTPa-HBV-IPV/Hib and anti-rotavirus IgA geometric mean titers. CONCLUSIONS: After a 2+1 schedule, V114 elicited non-inferior immune responses to 13 shared serotypes and superior responses to the two additional serotypes compared with PCV13, with comparable safety profile. These results support the routine use of V114 in infants. TRIAL REGISTRATION: ClinicalTrials.gov: NCT04031846; EudraCT: 2018-003787-31.


Assuntos
Infecções Pneumocócicas , Vacinas Pneumocócicas , Vacinas Conjugadas , Humanos , Lactente , Anticorpos Antibacterianos , Método Duplo-Cego , Imunogenicidade da Vacina , Imunoglobulina G , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/administração & dosagem , Vacinas Pneumocócicas/efeitos adversos , Streptococcus pneumoniae , Vacinação/métodos , Vacinas Conjugadas/administração & dosagem , Vacinas Conjugadas/efeitos adversos
18.
Hum Mol Genet ; 19(7): 1174-89, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20053665

RESUMO

While high levels of Pkd1 expression are detected in tissues of patients with autosomal dominant polycystic kidney disease (ADPKD), it is unclear whether enhanced expression could be a pathogenetic mechanism for this systemic disorder. Three transgenic mouse lines were generated from a Pkd1-BAC modified by introducing a silent tag via homologous recombination to target a sustained wild-type genomic Pkd1 expression within the native tissue and temporal regulation. These mice specifically overexpressed the Pkd1 transgene in extrarenal and renal tissues from approximately 2- to 15-fold over Pkd1 endogenous levels in a copy-dependent manner. All transgenic mice reproducibly developed tubular and glomerular cysts leading to renal insufficiency. Interestingly, Pkd1(TAG) mice also exhibited renal fibrosis and calcium deposits in papilla reminiscent of nephrolithiasis as frequently observed in ADPKD. Similar to human ADPKD, these mice consistently displayed hepatic fibrosis and approximately 15% intrahepatic cysts of the bile ducts affecting females preferentially. Moreover, a significant proportion of mice developed cardiac anomalies with severe left-ventricular hypertrophy, marked aortic arch distention and/or valvular stenosis and calcification that had profound functional impact. Of significance, Pkd1(TAG) mice displayed occasional cerebral lesions with evidence of ruptured and unruptured cerebral aneurysms. This Pkd1(TAG) mouse model demonstrates that overexpression of wild-type Pkd1 can trigger the typical adult renal and extrarenal phenotypes resembling human ADPKD.


Assuntos
Modelos Animais de Doenças , Doenças Renais Policísticas/genética , Canais de Cátion TRPP/genética , Animais , Pressão Sanguínea , Expressão Gênica , Coração/fisiopatologia , Rim/patologia , Rim/fisiopatologia , Expectativa de Vida , Fígado/patologia , Camundongos , Camundongos Transgênicos , Fenótipo , Doenças Renais Policísticas/patologia , Doenças Renais Policísticas/fisiopatologia , Canais de Cátion TRPP/metabolismo , Regulação para Cima
19.
BMC Health Serv Res ; 12: 64, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22420301

RESUMO

BACKGROUND: Telepathology, which is an emerging form of telemedicine in Canada, is defined as the electronic transmission of pathological images, usually derived from microscopes, from one location to another. There are various applications of telepathology, including case referral for an expert opinion, provision of an emergency service in the absence of a resident pathologist, and education. Until now, there has been relatively little use of telepathology for core diagnostic services in the absence of a local pathologist, but this practice is likely to increase in the future. The Laval University Integrated Health Network is in the process of deploying a telepathology system, primarily to provide an intraoperative frozen section service to small hospitals in sparsely populated areas which are experiencing a severe shortage of on-site pathologists. The telepathology project involves 17 hospitals located in five regions of eastern Quebec, Canada. This paper describes the study protocol that will be used to evaluate the benefits associated with the project. METHODS/DESIGN: A panel of experts was first assembled by Canada Health Infoway to agree on a set of benefits indicators that could be applied to all telepathology projects across Canada. Using the set of indicators as an input, we have developed a three-step study protocol. First, a survey questionnaire will be distributed to appraise the way pathologists, pathology technologists and surgeons perceive the telepathology system and its impacts. Second, a series of semi-structured interviews will be conducted with project leaders and telepathology users at sites that are representative of all the hospitals in the Laval University Integrated Health Network. The overall aim is to better understand the expected and unexpected effects of telepathology on health care professionals and patients as well as on the regional organization and delivery of care services. Finally, a pre-post design using secondary data is proposed to evaluate a wide array of tangible benefits to the patients, the health care providers, the hospitals, and the region as a whole. DISCUSSION: The Laval University Integrated Health Network's telepathology project is expected to yield positive and significant results that are relevant internationally. Our findings will provide valuable information on the nature and extent of benefits associated with telepathology systems intended to provide an intraoperative frozen section service to remote hospitals experiencing a shortage of specialists.


Assuntos
Redes de Comunicação de Computadores/organização & administração , Serviços Hospitalares Compartilhados/organização & administração , Telepatologia/organização & administração , Redes de Comunicação de Computadores/tendências , Secções Congeladas , Serviços Hospitalares Compartilhados/tendências , Humanos , Área Carente de Assistência Médica , Estudos de Casos Organizacionais , Avaliação de Programas e Projetos de Saúde , Quebeque , Telepatologia/tendências
20.
Med Sci (Paris) ; 28(11): 993-9, 2012 Nov.
Artigo em Francês | MEDLINE | ID: mdl-23171906

RESUMO

The aim of the Eastern Québec telepathology network is to provide uniform diagnostic telepathology services across a huge geographic region with a low population density. This project is intended to provide surgeons and pathologists with frozen section and second opinion services anywhere and at any time across the entire region, in order to avoid unnecessary patient transfer. The project has been implemented in 21 sites, each equipped with a whole slide scanner, a macroscopy station, a videoconferencing device and a viewer/case management and collaboration solution. Of the 21 sites, 6 are devoid of a pathology laboratory, two have no pathologist and 5 have only one pathologist on site. Signs of improvement of medical care in this region are already apparent since the Eastern Québec telepathology network has been implemented. However, it is important not to underestimate the challenges related to change management in the course of implementation of such a new technology.


Assuntos
Telepatologia/organização & administração , Anatomia/organização & administração , Comportamento Cooperativo , Previsões , Secções Congeladas , Cirurgia Geral/organização & administração , Humanos , Serviços de Informação , Comunicação Interdisciplinar , Internet , Patologia Clínica/organização & administração , Garantia da Qualidade dos Cuidados de Saúde , Quebeque , Encaminhamento e Consulta , Telepatologia/instrumentação , Telepatologia/métodos , Telepatologia/tendências , Universidades/organização & administração
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