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1.
Gynecol Oncol Rep ; 53: 101380, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38601712

RESUMO

Dedifferentiated endometrial carcinoma is a rare, highly aggressive subtype of endometrial cancer associated with poor survival outcomes. Current guidelines recommend treatment of advanced-stage disease with surgical staging or cytoreduction and platinum/taxane-based chemotherapy. Despite these approaches, the achievement of long-term remission or prolonged survival is challenging. Recent Phase III studies demonstrate that the addition of PD-1 inhibitors to standard chemotherapy significantly improves progression-free survival in patients with measurable, mismatch repair deficient (dMMR) and proficient (pMMR) advanced-stage or recurrent endometrial carcinoma. However, the role of PD-1 blockade in the treatment of undifferentiated and dedifferentiated endometrial carcinoma remains unclear, as very few patients with these cancer subtypes were included in the trials. In this case report, we present a patient with dMMR dedifferentiated endometrial carcinoma, treated with primary surgery to no gross residual disease, followed by carboplatin/paclitaxel chemotherapy and a short course of maintenance pembrolizumab. To date, the patient remains with a prolonged disease-free survival of 61 months, supporting the potential use of PD-1 inhibitors in the upfront treatment of unmeasurable, advanced-stage, dMMR dedifferentiated endometrial carcinoma.

3.
Cureus ; 16(2): e53822, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38465162

RESUMO

Cerebral aneurysms are rarely encountered in pregnancy. Their antepartum and intrapartum management remain clinically challenging, primarily due to concern regarding potential rupture. We present a case of a patient in preterm labor at risk for imminent delivery with a 10mm cerebral aneurysm. She was recommended for cesarean section (CS), yet delivered via spontaneous vaginal delivery in the operating room after induction of general anesthesia for the intended CS. Her aneurysm and neurologic function remained intact postpartum. Cerebral aneurysms <5mm are unlikely to undergo significant growth during pregnancy. The presence of a cerebral aneurysm is not automatically a contraindication to the Valsalva maneuver. The recommendation for which patients with unruptured cerebral aneurysms should deliver by CS, operative vaginal delivery, or unassisted vaginal delivery (i.e., which patients should avoid Valsalva maneuver intrapartum), is complex and requires multidisciplinary discussion.

4.
Med Teach ; : 1-4, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38350453

RESUMO

EDUCATIONAL CHALLENGE: Each year, adverse events are reported in healthcare, of which many relate to healthcare workforce cognitive bias. The active involvement of workforce and consumers in the review and co-design of effective training for the healthcare workforce to recognise, monitor, and manage unconscious bias is required. PROPOSED SOLUTION: We used participatory action research to co-design an innovative, interprofessional simulation based on 'real world' clinical incidents and lived experiences to improve the delivery of safe, high quality, consumer-focused healthcare. Following ethics approval, content analysis of serious adverse patient safety events involving cognitive bias was conducted. These data informed audio-recorded interviews with the healthcare workforce and consumers to explore their experiences of cognitive bias. Following thematic analysis, key themes of communication, stigma, diagnostic overshadowing, and fragmented systems were uncovered. Guided by consumers, these themes were interwoven into a simulation scenario that included real places, stories, and verbatim quotes delivered through mixed media artefacts. This heightened the immersive and experiential learning that aimed to uncover unconscious bias and help learners recognise its impact on clinical decisions and practice. POTENTIAL BENEFITS AND NEXT STEPS: To our knowledge, this is the first interprofessional, co-designed simulation to specifically address cognitive bias in current and future healthcare workforce. Plans to translate this research into a practical framework on how to work with key stakeholders (including consumers) to identify 'real-world' health service risks and co-design targeted simulations to address these gaps are described, including lessons learned.

5.
Front Physiol ; 13: 884166, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574458

RESUMO

Cystic fibrosis (CF) airway disease is characterized by excessive and accumulative mucus in the airways. Mucociliary clearance becomes defective as mucus secretions become hyperconcentrated and viscosity increases. The CFTR-knockout (KO) rat has been previously shown to progressively develop delayed mucociliary transport, secondary to increased viscoelasticity of airway secretions. The humanized-G551D CFTR rat model has demonstrated that abnormal mucociliary clearance and hyperviscosity is reversed by ivacaftor treatment. In this study, we sought to identify the components of mucus that changes as the rat ages to contribute to these abnormalities. We found that Muc5b concentrations, and to a lesser extent Muc5ac, in the airway were increased in the KO rat compared to WT, and that Muc5b concentration was directly related to the viscosity of the mucus. Additionally, we found that methacholine administration to the airway exacerbates these characteristics of disease in the KO, but not WT rat trachea. Lastly we determined that at 6 months of age, CF rats had mucus that was adherent to the airway epithelium, a process that is reversed by ivacaftor therapy in the hG551D rat. Overall, these data indicate that accumulation of Muc5b initiates the muco-obstructive process in the CF lung prior to infection.

6.
Eur Respir J ; 2022 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115338

RESUMO

Cystic fibrosis (CF) airway disease is characterised by chronic Pseudomonas aeruginosa infection. Successful eradication strategies have been hampered by a poor understanding of the mechanisms underlying conversion to chronicity. The CFTR-knockout (KO) rat harbors a progressive defect in mucociliary transport and viscosity. KO rats were infected before and after the appearance of the mucus defect, using a clinical, mucoid-isolate of P. aeruginosa embedded in agarose beads. Young KO rats that were exposed to bacteria before the development of mucociliary transport defects resolved the infection and subsequent tissue damage. However, older KO rats that were infected in the presence of hyperviscous and static mucus were unable to eradicate bacteria, but instead had bacterial persistence through 28 days post-infection that was accompanied by airway mucus occlusion and lingering inflammation. Normal rats responded to infection with increased mucociliary transport to supernormal rates, which reduced the severity of a second bacterial exposure. We therefore conclude that the aberrant mucus present in the CF airway permits persistence of P. aeruginosa in the lung.

7.
Genes Dis ; 9(1): 108-115, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35005111

RESUMO

Chronic pancreatitis (CP) is a major risk factor of pancreatic ductal adenocarcinoma (PDAC). How CP promotes pancreatic oncogenesis remains unclear. A characteristic feature of PDAC is its prominent desmoplasia in the tumor microenvironment, composed of activated fibroblasts and macrophages. Macrophages can be characterized as M1 or M2, with tumor-inhibiting or -promoting functions, respectively. We reported that Gremlin 1 (GREM1), a key pro-fibrogenic factor, is upregulated in the stroma of CP. The current study aimed to investigate the expression of GREM1 and correlation between GREM1 and macrophages within the pancreas during chronic inflammation and the development of PDAC. By mRNA in situ hybridization, we detected GREM1 mRNA expression within α-smooth muscle actin (SMA)-positive fibroblasts of the pancreatic stroma. These designated FibroblastsGrem1+ marginally increased from CP to pancreatic intraepithelial neoplasia (PanIN) and PDAC. Within PDAC, FibroblastsGrem1+ increased with higher pathological tumor stages and in a majority of PDAC subtypes screened. Additionally, FibroblastsGrem1+ positively correlated with total macrophages (MacCD68+) and M2 macrophages (M2CD163+) in PDAC. To begin exploring potential molecular links between FibroblastsGrem1+ and macrophages in PDAC, we examined the expression of macrophage migration inhibitory factor (MIF), an endogenous counteracting molecule of GREM1 and an M1 macrophage promoting factor. By IHC staining of MIF, we found MIF to be expressed by tumor cells, positively correlated with GREM1; by IHC co-staining, we found MIF to be negatively correlated with M2CD163+ expression. Our findings suggest that GREM1 expression by activated fibroblasts may promote PDAC development, and GREM1/MIF may play an important role in macrophage phenotype.

8.
Clin Nurs Res ; 31(5): 782-794, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34293956

RESUMO

Patients are central to healthcare clinicians and organizations but often subsidiary to clinical expertise, knowledge, workplace processes, and culture. Shifting societal values, technology, and regulations have remoulded the patient-clinician relationship, augmenting the patient's voice within the healthcare construct. Scaffolding this restructure is the global imperative to deliver person-centered care (PCC). The aim of the scoping review was to explore and map the intersection between patient feedback and strategies to improve the provision of PCC within acute hospitals in Australia. Database searches yielded 493 articles, with 16 studies meeting inclusion criteria. Integration of patient feedback varied from strategy design, through to multi-staged input throughout the initiative and beyond. Initiatives actioning patient feedback fell broadly into four categories: clinical practice, educational strategies, governance, and measurement. How clinicians can invite feedback and support patients to engage equally remains unclear, requiring further exploration of strategies to propel clinician-patient partnerships, scaffolded by hospital governance structures.


Assuntos
Hospitais , Autocuidado , Austrália , Retroalimentação , Humanos , Assistência Centrada no Paciente
9.
Mediators Inflamm ; 2021: 5595464, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34104113

RESUMO

We have previously demonstrated that the pancreas can recover from chronic pancreatitis (CP) lesions in the cerulein-induced mouse model. To explore how pancreatic recovery is achieved at the molecular level, we used RNA-sequencing (seq) and profiled transcriptomes during CP transition to recovery. CP was induced by intraperitoneally injecting cerulein in C57BL/6 mice. Time-matched controls (CON) were given normal saline. Pancreata were harvested from mice 4 days after the final injections (designated as CP and CON) or 4 weeks after the final injections (designated as CP recovery (CPR) and control recovery (CONR)). Pancreatic RNAs were extracted for RNA-seq and quantitative (q) PCR validation. Using RNA-seq, we identified a total of 3,600 differentially expressed genes (DEGs) in CP versus CON and 166 DEGs in CPR versus CONR. There are 132 DEGs overlapped between CP and CPR and 34 DEGs unique to CPR. A number of selected pancreatic fibrosis-relevant DEGs were validated by qPCR. The top 20 gene sets enriched from DEGs shared between CP and CPR are relevant to extracellular matrix and cancer biology, whereas the top 10 gene sets enriched from DEGs specific to CPR are pertinent to DNA methylation and specific signaling pathways. In conclusion, we identified a distinct set of DEGs in association with extracellular matrix and cancer cell activities to contrast CP and CPR. Once during ongoing CP recovery, DEGs relevant to DNA methylation and specific signaling pathways were induced to express. The DEGs shared between CP and CPR and the DEGs specific to CPR may serve as the unique transcriptomic signatures and biomarkers for determining CP recovery and monitoring potential therapeutic responses at the molecular level to reflect pancreatic histological resolution.


Assuntos
Regulação da Expressão Gênica , Pâncreas/metabolismo , Pancreatite Crônica/metabolismo , Pancreatite Crônica/terapia , Transcriptoma , Animais , Ceruletídeo/metabolismo , Colecistocinina/metabolismo , Modelos Animais de Doenças , Matriz Extracelular/metabolismo , Feminino , Perfilação da Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA-Seq , Transdução de Sinais
10.
Cell Biosci ; 11(1): 28, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531047

RESUMO

BACKGROUND: A systemic evaluation of immune cell infiltration patterns in experimental acute pancreatitis (AP) is lacking. Using multi-dimensional flow cytometry, this study profiled infiltrating immune cell types in multiple AP mouse models. METHODS: Three AP models were generated in C57BL/6 mice via cerulein (CAE) injection, alcohol and palmitoleic acid (EtOH + POA) injection, and alcohol diet feeding and cerulein (EtOH + CAE) injection. Primary pancreatic cells and splenocytes were prepared, and multi-dimensional flow cytometry was performed and analyzed by manual gating and computerized PhenoGraph, followed by visualization with t-distributed stochastic neighbor embedding (t-SNE). RESULTS: CAE treatment induced a time-dependent increase of major innate immune cells and a decrease of follicular B cells, and TCD4+ cells and the subtypes in the pancreas, whereas elicited a reversed pattern in the spleen. EtOH + POA treatment resulted in weaker effects than CAE treatment. EtOH feeding enhanced CAE-induced amylase secretion, but unexpectedly attenuated CAE-induced immune cell regulation. In comparison with manual gating analysis, computerized analysis demonstrated a remarkable time efficiency and reproducibility on the innate immune cells and B cells. CONCLUSIONS: The reverse pattern of increased innate and decreased adaptive immune cells was consistent in the pancreas in CAE and EtOH + POA treatments. Alcohol feeding opposed the CAE effect on immune cell regulation. Together, the immune profiling approach utilized in this study provides a better understanding of overall immune responses in AP, which may facilitate the identification of intervention windows and new therapeutic strategies. Computerized analysis is superior to manual gating by dramatically reducing analysis time.

11.
J Clin Med ; 10(2)2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33467580

RESUMO

The incidence of acute and chronic pancreatitis is increasing in the United States. Rates of acute pancreatitis (AP) are similar in both sexes, but chronic pancreatitis (CP) is more common in males. When stratified by etiology, women have higher rates of gallstone AP, while men have higher rates of alcohol- and tobacco-related AP and CP, hypercalcemic AP, hypertriglyceridemic AP, malignancy-related AP, and type 1 autoimmune pancreatitis (AIP). No significant sex-related differences have been reported in medication-induced AP or type 2 AIP. Whether post-endoscopic retrograde cholangiopancreatography pancreatitis is sex-associated remains controversial. Animal models have demonstrated sex-related differences in the rates of induction and severity of AP, CP, and AIP. Animal and human studies have suggested that a combination of risk factor profiles, as well as genes, may be responsible for the observed differences. More investigation into the sex-related differences of AP and CP is desired in order to improve clinical management by developing effective prevention strategies, diagnostics, and therapeutics.

12.
Am J Respir Crit Care Med ; 202(9): 1271-1282, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32584141

RESUMO

Rationale: Animal models have been highly informative for understanding the characteristics, onset, and progression of cystic fibrosis (CF) lung disease. In particular, the CFTR-/- rat has revealed insights into the airway mucus defect characteristic of CF but does not replicate a human-relevant CFTR (cystic fibrosis transmembrane conductance regulator) variant.Objectives: We hypothesized that a rat expressing a humanized version of CFTR and harboring the ivacaftor-sensitive variant G551D could be used to test the impact of CFTR modulators on pathophysiologic development and correction.Methods: In this study, we describe a humanized-CFTR rat expressing the G551D variant obtained by zinc finger nuclease editing of a human complementary DNA superexon, spanning exon 2-27, with a 5' insertion site into the rat gene just beyond intron 1. This targeted insertion takes advantage of the endogenous rat promoter, resulting in appropriate expression compared with wild-type animals.Measurements and Main Results: The bioelectric phenotype of the epithelia recapitulates the expected absence of CFTR activity, which was restored with ivacaftor. Large airway defects, including depleted airway surface liquid and periciliary layers, delayed mucus transport rates, and increased mucus viscosity, were normalized after the administration of ivacaftor.Conclusions: This model is useful to understand the mechanisms of disease and the extent of pathology reversal with CFTR modulators.


Assuntos
Aminofenóis/uso terapêutico , Agonistas dos Canais de Cloreto/uso terapêutico , Regulador de Condutância Transmembrana em Fibrose Cística/efeitos dos fármacos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/tratamento farmacológico , Fibrose Cística/genética , Muco/efeitos dos fármacos , Quinolonas/uso terapêutico , Animais , Humanos , Modelos Animais , Ratos
13.
Shock ; 53(5): 646-652, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31454826

RESUMO

Resuscitation with human fresh frozen plasma (FFP) in hemorrhagic shock (HS) patients is associated with improved clinical outcomes. Our group has demonstrated that the beneficial effect of FFP is due to its blockade on endothelial hyperpermeability, thereby improving vascular barrier function. The current study aimed to investigate HS-induced endothelial cell apoptosis, a potential major contributor to the endothelial hyperpermeability, and to determine the effect and the key components/factors of FFP on protecting endothelial cells from apoptosis. We first measured and demonstrated an increase in apoptotic endothelial microparticles (CD146AnnexinV) in patients in shock compared to normal subjects, indicating the induction of endothelial cell activation and apoptosis in shock patients. We then transfused HS rats with FFP and showed that FFP blocked HS-induced endothelial cell apoptosis in gut tissue. To identify the anti-apoptotic factors in FFP, we utilized high-performance liquid chromatography, fractionated FFP, and screened the fractions in vitro for the anti-apoptotic effects. We selected the most effective fractions, performed mass spectrometry, and identified fibrinogen as a potent anti-apoptotic factor. Taken together, our findings suggest that HS-induced endothelial apoptosis may constitute a major mechanism underlying the vascular hyperpermeability. Furthermore, the identified anti-apoptotic factor fibrinogen may contribute to the beneficial effects of FFP resuscitation, and therefore, may have therapeutic potential for HS.


Assuntos
Células Endoteliais/fisiologia , Fibrinogênio/fisiologia , Plasma/citologia , Choque/patologia , Choque/terapia , Ferimentos e Lesões/complicações , Animais , Apoptose , Estudos de Casos e Controles , Técnicas de Cultura de Células , Citoproteção , Modelos Animais de Doenças , Células Endoteliais/patologia , Humanos , Ratos , Ferimentos e Lesões/patologia , Ferimentos e Lesões/terapia
14.
BMJ Open ; 9(12): e030301, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31843821

RESUMO

INTRODUCTION: Home care clients are increasingly medically complex, have limited access to effective chronic disease management and have very high emergency department (ED) visitation rates. There is a need for more appropriate and targeted supportive chronic disease management for home care clients. We aim to evaluate the effectiveness and preliminary cost effectiveness of a targeted, person-centred cardiorespiratory management model. METHODS AND ANALYSIS: The Detection of Indicators and Vulnerabilities of Emergency Room Trips (DIVERT) - Collaboration Action Research and Evaluation (CARE) trial is a pragmatic, cluster-randomised, multicentre superiority trial of a flexible multicomponent cardiorespiratory management model based on the best practice guidelines. The trial will be conducted in partnership with three regional, public-sector, home care providers across Canada. The primary outcome of the trial is the difference in time to first unplanned ED visit (hazard rate) within 6 months. Additional secondary outcomes are to identify changes in patient activation, changes in cardiorespiratory symptom frequencies and cost effectiveness over 6 months. We will also investigate the difference in the number of unplanned ED visits, number of inpatient hospitalisations and changes in health-related quality of life. Multilevel proportional hazard and generalised linear models will be used to test the primary and secondary hypotheses. Sample size simulations indicate that enrolling 1100 home care clients across 36 clusters (home care caseloads) will yield a power of 81% given an HR of 0.75. ETHICS AND DISSEMINATION: Ethics approval was obtained from the Hamilton Integrated Research Ethics Board as well as each participating site's ethics board. Results will be submitted for publication in peer-reviewed journals and for presentation at relevant conferences. Home care service partners will also be informed of the study's results. The results will be used to inform future support strategies for older adults receiving home care services. TRIAL REGISTRATION NUMBER: NCT03012256.


Assuntos
Insuficiência Cardíaca/terapia , Serviços de Assistência Domiciliar , Insuficiência Respiratória/terapia , Canadá , Análise Custo-Benefício , Serviço Hospitalar de Emergência/estatística & dados numéricos , Utilização de Instalações e Serviços , Serviços de Assistência Domiciliar/economia , Hospitalização/estatística & dados numéricos , Humanos , Modelos de Riscos Proporcionais , Qualidade de Vida , Tempo para o Tratamento
15.
Artigo em Inglês | MEDLINE | ID: mdl-32211568

RESUMO

Bone morphogenetic proteins (BMPs) comprise a major subgroup of the transforming growth factor (TGF)-ß superfamily. They play pivotal roles in embryonic development and tissue homeostasis in adults. Deregulation of BMP and TGF-ß signaling contributes to developmental anomalies and multiple diseases. In this mini-review, we focus on BMP signaling in inflammatory disorders of the pancreas, acute and chronic pancreatitis, in contrast to TGF-ß signaling. We then discuss molecular mechanisms that interact with and connect between the BMP and TGF-ß signaling pathways. Lastly, we review potential implications of these molecular mechanisms for therapeutic development. In summary, BMP signaling pathway plays different roles during pancreatitis disease development, and the antagonism between BMP and TGF-ß signaling can be manipulated for therapeutic development against pancreatitis.

16.
JCI Insight ; 3(1)2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29321377

RESUMO

The mechanisms underlying the development and natural progression of the airway mucus defect in cystic fibrosis (CF) remain largely unclear. New animal models of CF, coupled with imaging using micro-optical coherence tomography, can lead to insights regarding these questions. The Cftr-/- (KO) rat allows for longitudinal examination of the development and progression of airway mucus abnormalities. The KO rat exhibits decreased periciliary depth, hyperacidic pH, and increased mucus solid content percentage; however, the transport rates and viscoelastic properties of the mucus are unaffected until the KO rat ages. Airway submucosal gland hypertrophy develops in the KO rat by 6 months of age. Only then does it induce increased mucus viscosity, collapse of the periciliary layer, and delayed mucociliary transport; stimulation of gland secretion potentiates this evolution. These findings could be reversed by bicarbonate repletion but not pH correction without counterion donation. These studies demonstrate that abnormal surface epithelium in CF does not cause delayed mucus transport in the absence of functional gland secretions. Furthermore, abnormal bicarbonate transport represents a specific target for restoring mucus clearance, independent of effects on periciliary collapse. Thus, mature airway secretions are required to manifest the CF defect primed by airway dehydration and bicarbonate deficiency.


Assuntos
Fibrose Cística/terapia , Muco/metabolismo , Mucosa Respiratória/metabolismo , Animais , Bicarbonatos/metabolismo , Transporte Biológico , Fibrose Cística/patologia , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Transporte de Íons , Masculino , Depuração Mucociliar , Ratos , Mucosa Respiratória/patologia , Propriedades de Superfície
17.
JOP ; 19(5): 236-243, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30636940

RESUMO

OBJECTIVE: The cerulein-induced mouse pancreatitis model is a well-established, commonly used representation of human chronic pancreatitis pathology. Although studies report sex-dependent differences in human chronic pancreatitis, there are no studies in this model directly comparing sex response to pancreatic injury and recovery. Therefore, we designed a study to investigate whether sex- dependent differences in chronic pancreatitis injury and recovery exist in the cerulein-induced pancreatitis model. METHODS: Adult male and female C57BL/6 mice were administered cerulein (50 µg/kg, 5 hourly intraperitoneal injections/day, 3 days/week) for 4 weeks to induce chronic pancreatitis; control mice received normal saline injections. Pancreata and blood were harvested at 4 days (as injury group) or 4 weeks (as recovery group) after the last injection. Amylase secretion was measured from the serum. Acinar injury was scored on H&E sections. Fibrosis was assessed by Sirius Red and collagen immunofluorescence staining. RESULTS: Compared to time-matched controls, injury group displayed decreased body and pancreas weight, and increased acinar injury and fibrosis, with no significant differences between males and females. Recovery group demonstrated recovery of body weight, partial recovery of pancreas weight, reversal of acinar injury, and partial reversal of fibrosis, with no significant differences between males and females. Amylase secretion/body weight was similar across all groups. CONCLUSIONS: Male and female mice of the cerulein-induced chronic pancreatitis demonstrate similar responses to chronic pancreatitis injury and recovery. Although this model may not sufficiently emulate sex-dependent responses in human chronic pancreatitis, our study supports that both sexes of mice from this model can be used for the study of chronic pancreatitis.

18.
Mol Neurodegener ; 12(1): 33, 2017 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-28472993

RESUMO

BACKGROUND: The experience from clinical trials indicates that anti-Aß immunotherapy could be effective in early/pre-clinical stages of AD, whereas at the late stages promoting the clearing of Aß alone may be insufficient to halt the disease progression. At the same time, pathological tau correlates much better with the degree of dementia than Aß deposition. Therefore, targeting pathological tau may provide a more promising approach for the treatment of advanced stages of AD. Recent data demonstrates that the N-terminal region of tau spanning aa 2-18 termed "phosphatase activation domain" that is normally hidden in the native protein in 'paperclip'-like conformation, becomes exposed in pathological tau and plays an essential role in the inhibition of fast axonal transport and in aggregation of tau. Hence, we hypothesized that anti-Tau2-18 monoclonal antibodies (mAb) may recognize pathological, but not normal tau at very early stages of tauopathy and prevent or decrease the aggregation of this molecule. METHODS: Mouse mAbs were generated using standard hybridoma methodology. CDR grafting was used for humanization of mouse mAb. Humanized mAb (Armanezumab) was characterized and tested in vitro/ex vivo/in vivo using biochemical and immunological methods (HPLC, Biacore, ELISA, IHC, FRET, etc.). Stable DG44 cell line expressing Armanezumab was generated by clone selection with increased concentrations of methotrexate (MTX). RESULTS: A panel of mouse mAbs was generated, clone 1C9 was selected based on binding to pathological human tau with high affinity and humanized. Fine epitope mapping revealed conservation of the epitope of human tau recognized by the parent murine mAb and Armanezumab. Importantly, Armanezumab (i) bound to tau with high affinity as determined by Biacore; (ii) bound pathological tau in brains from AD, FTD and Pick's disease cases; (iii) inhibited seeding effect of aggregated tau from brain lysate of P301S Tg mice; (iv) inhibited cytotoxic effect of tau oligomers; (v) reduced total tau (HT7) and AT100, PHF1, AT8, AT180, p212, p214-positive tau species in brains of tau transgenic mice after intracranial injection. A stable CHO cell line producing >1.5 g/l humanized mAb, Armanezumab was generated. CONCLUSION: These findings suggest that Armanezumab could be therapeutic in clinical studies for treatment of AD.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Encéfalo/efeitos dos fármacos , Tauopatias , Proteínas tau/antagonistas & inibidores , Animais , Especificidade de Anticorpos , Humanos , Camundongos , Camundongos Transgênicos
19.
Vaccine ; 35(16): 2015-2024, 2017 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-28320590

RESUMO

BACKGROUND: By the time clinical symptoms of Alzheimer's disease (AD) manifest in patients there is already substantial tau pathology in the brain. Recent evidence also suggests that tau pathology can become self-propagating, further accelerating disease progression. Over the last decade several groups have tested the efficacy of protein-based anti-tau immunotherapeutics in various animal models of tauopathy. Here we report on the immunological and therapeutic potency of the first anti-tau DNA vaccine based on the MultiTEP platform, AV-1980D, in THY-Tau22 transgenic mice. METHODS: Starting at 3months of age, mice were immunized intramuscularly with AV-1980D vaccine targeting a tau B cell epitope spanning aa2-18 followed by electroporation (EP). Humoral and cellular immune responses in vaccinated animals were analyzed by ELISA and ELISpot, respectively. Neuropathological changes in the brains of experimental and control mice were then analyzed by biochemical (WB and ELISA) and immunohistochemical (IHC) methods at 9months of age. RESULTS: EP-mediated AV-1980D vaccinations of THY-Tau22 mice induced activation of Th cells specific to the MultiTEP vaccine platform and triggered robust humoral immunity response specific to tau. Importantly, no activation of potentially harmful autoreactive Th cell responses specific to endogenous tau species was detected. The maximum titers of anti-tau antibodies were reached after two immunizations and remained slightly lower, but steady during five subsequent monthly immunizations. Vaccinations with AV-1980D followed by EP significantly reduced total tau and pS199 and AT180 phosphorylated tau levels in the brains extracts of vaccinated mice, but produced on subtle non-significant effects on other phosphorylated tau species. CONCLUSIONS: These data demonstrate that MultiTEP-based DNA epitope vaccination targeting the N-terminus of tau is highly immunogenic and therapeutically potent in the THY-Tau22 mouse model of tauopathy and indicate that EP-mediated DNA immunization is an attractive alternative to protein-based adjuvanted vaccines for inducing high concentrations of anti-tau antibodies.


Assuntos
Doença de Alzheimer/prevenção & controle , Doença de Alzheimer/terapia , Epitopos/imunologia , Vacinas de DNA/imunologia , Proteínas tau/imunologia , Imunidade Adaptativa , Doença de Alzheimer/patologia , Animais , Anticorpos/sangue , Western Blotting , Encéfalo/patologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , ELISPOT , Epitopos/genética , Feminino , Humanos , Imuno-Histoquímica , Injeções Intramusculares , Linfócitos/imunologia , Camundongos Transgênicos , Resultado do Tratamento , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Proteínas tau/genética
20.
Pediatrics ; 139(2)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28143919

RESUMO

BACKGROUND AND OBJECTIVES: Cystic fibrosis (CF) is known for its impact on the lung and pancreas of individuals; however, impaired growth is also a common complication. We hypothesized that targeting the biological defect in the CF transmembrane conductance regulator (CFTR) protein may affect growth outcomes. METHODS: In this post hoc analysis, we assessed linear growth and weight in 83 children (aged 6-11 years) enrolled in 2 clinical trials, the longitudinal-observation GOAL study and the placebo-controlled ENVISION study, to evaluate the effects of ivacaftor, a CFTR potentiator. We calculated height and weight z scores and height and weight growth velocities (GVs). RESULTS: In ivacaftor-treated children in GOAL, height and weight z scores increased significantly from baseline to 6 months (increases of 0.1 [P < .05] and 0.26 [P < .0001], respectively); height GV increased significantly from 3 to 6 months (2.10-cm/year increase; P < .01). In ivacaftor-treated children in ENVISION, height and weight z scores increased significantly from baseline to 48 weeks (increases of 0.17 [P < .001] and 0.35 [P < .001], respectively). Height and weight GVs from baseline to 48 weeks were also significantly higher with ivacaftor than with placebo (differences of 1.08 cm/year [P < .05] and 3.11 kg/year [P < .001], respectively). CONCLUSIONS: Ivacaftor treatment in prepubescent children may help to address short stature and altered GV in children with CF; results from these analyses support the existence of an intrinsic defect in the growth of children with CF that may be ameliorated by CFTR modulation.


Assuntos
Aminofenóis/uso terapêutico , Fibrose Cística/tratamento farmacológico , Quinolonas/uso terapêutico , Estatura/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Criança , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Resultado do Tratamento
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