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1.
Ann Rheum Dis ; 83(5): 599-607, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38228361

RESUMO

OBJECTIVES: The study aimed to evaluate the effect of adding a non-steroidal anti-inflammatory drug (NSAID), celecoxib (CEL), to a tumour necrosis factor inhibitor (TNFi), golimumab (GOL), compared with TNFi monotherapy on radiographic spinal progression in patients with radiographic axial spondyloarthritis (r-axSpA) over 2 years. METHODS: R-axSpA patients, having risk factors for radiographic progression (high disease activity plus C reactive protein >5 mg/L and/or ≥1 syndesmophyte(s)), underwent a 12-week run-in phase with GOL 50 mg every 4 weeks. In the core phase (96 weeks), only patients with a good clinical response at week 12 were randomised (1:1) to GOL+CEL 200 mg two times per day (combination therapy) or GOL monotherapy. The primary endpoint was radiographic progression assessed by modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS) change at week 108 in the intent-to-treat population. RESULTS: A total of 128 patients were enrolled in the run-in phase; and 109 patients were randomised at week 12 to monotherapy (n=55) or combination therapy (n=54). At week 108, 97 (52 vs 45) patients completed the study. The change in mSASSS at week 108 was 1.7 (95% CI 0.8 to 2.6) in the monotherapy vs 1.1 (95% CI 0.4 to 1.8) in the combination therapy groups (p=0.79). New syndesmophytes occurred in 25% of patients in the monotherapy vs 11% of patients in the combination therapy groups (p=0.12). During the study, no significant differences in adverse events and serious adverse events were observed between the groups. CONCLUSIONS: Combination therapy with GOL+CEL did not demonstrate statistically significant superiority over GOL monotherapy in retarding radiographic spinal progression over 2 years in r-axSpA.


Assuntos
Espondiloartropatias , Espondilite Anquilosante , Humanos , Anti-Inflamatórios não Esteroides/uso terapêutico , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Radiografia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/patologia , Espondilite Anquilosante/tratamento farmacológico , Celecoxib/uso terapêutico , Espondiloartropatias/tratamento farmacológico , Progressão da Doença
2.
Bioconjug Chem ; 35(9): 1402-1416, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39185789

RESUMO

The Al18F-labeling approach offers a one-step access to radiofluorinated biomolecules by mimicking the labeling process for radiometals. Although these labeling conditions are considered to be mild compared to classic radiofluorinations, improvements of the chelating units have led to the discovery of (±)-H3RESCA, which allows Al18F-labeling already at ambient temperature. While the suitability of (±)-H3RESCA for functionalization and radiofluorination of proteins is well established, its use for small molecules or peptides is less explored. Herein, we advanced this acyclic pentadentate ligand by introducing an alkyne moiety for the late-stage functionalization of biomolecules via click chemistry. We show that in addition to Al18F-labeling, the cyclohexanediamine triazole (CHDT) moiety allows stable complexation of 68Ga and 111In. Three novel CHDT-functionalized PSMA inhibitors were synthesized and their Al18F-, 68Ga-, and 111In-labeled analogs were subjected to a detailed in vitro radiopharmacological characterization. Stability studies in vitro in human serum revealed among others a high kinetic inertness of all radiometal complexes. Furthermore, the Al18F-labeled PSMA ligands were characterized for their biodistribution in a LNCaP derived tumor xenograft mouse model by PET imaging. One radioligand, Al[18F]F-CHDT-PSMA-1, bearing a small azidoacetyl linker at the glutamate-urea-lysine motif, provided an in vivo performance comparable to that of [18F]PSMA-1007 but with even higher tumor-to-blood and tumor-to-muscle ratios at 120 min p.i. Overall, our results highlight the suitability of the novel CHDT moiety for functionalization and radiolabeling of small molecules or peptides with Al18F, 68Ga, and 111In and the triazole ring seems to entail favorable pharmacokinetic properties for molecular imaging purposes.


Assuntos
Radioisótopos de Flúor , Triazóis , Animais , Triazóis/química , Triazóis/farmacocinética , Humanos , Camundongos , Radioisótopos de Flúor/química , Radioisótopos de Gálio/química , Compostos Radiofarmacêuticos/química , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/síntese química , Masculino , Linhagem Celular Tumoral , Química Click , Distribuição Tecidual
3.
Clin Exp Rheumatol ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39360371

RESUMO

OBJECTIVES: Despite significant savings with biosimilars, their negative perception can lead to the occurrence of a nocebo effect (NE), therefore we aimed to quantify the NE in inflammatory rheumatism after switching from adalimumab or etanercept originators to biosimilars. METHODS: This retrospective study was conducted in 4 hospitals in Normandy, France between January 2018 and July 2022. The study included patients with rheumatoid arthritis or spondyloarthritis in remission under adalimumab or etanercept originators before switching to biosimilars. The occurrence of a NE was considered in patients who did not maintain biosimilars at 12 months and who presented a subjective adverse event (AE). A comparative analysis of the quantitative data collected before and after switching was performed. The AE that led to biosimilar discontinuation was identified. Additional analyses were performed to identify potential risk factors for the occurrence of a NE. RESULTS: Among 183 patients included,13.1% presented a NE. Objective AEs were observed, including rheumatism reactivation (15.3%), intolerance (8.2%), infection (1.6%) and allergic reactions (0.5%). Morning stiffness duration was significantly different before and after the switch in the spondyloarthritis group (p=0.01). No risk factors were associated with the occurrence of a NE within the limits of the studied parameters. CONCLUSIONS: The occurrence of a NE after switching to a biosimilar remains acceptable. It appears less frequent when the switch is supervised by the practitioner rather than being systematic (up to 33% in some countries). A shared medical decision seems to be essential in a subset of patients, which remains to be defined.

4.
Hepatology ; 75(4): 866-880, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34687060

RESUMO

BACKGROUND AND AIMS: Pluripotent stem cell-derived hepatocytes differentiated in monolayer culture are known to have more fetal than adult hepatocyte characteristics. If numerous studies tend to show that this immature phenotype might not necessarily be an obstacle to their use in transplantation, other applications such as drug screening, toxicological studies, or bioartificial livers are reliant on hepatocyte functionality and require full differentiation of hepatocytes. New technologies have been used to improve the differentiation process in recent years, usually evaluated by measuring the albumin production and CYP450 activity. Here we used the complex production and most importantly the activity of the coagulation factor IX (FIX) produced by mature hepatocytes to assess the differentiation of hemophilia B (HB) patient's induced pluripotent stem cells (iPSCs) in both monolayer culture and organoids. APPROACH AND RESULTS: Indeed, HB is an X-linked monogenic disease due to an impaired activity of FIX synthesized by hepatocytes in the liver. We have developed an in vitro model of HB hepatocytes using iPSCs generated from fibroblasts of a severe HB patient. We used CRISPR/Cas9 technology to target the genomic insertion of a coagulation factor 9 minigene bearing the Padua mutation to enhance FIX activity. Noncorrected and corrected iPSCs were differentiated into hepatocytes under both two-dimensional and three-dimensional differentiation protocols and deciphered the production of active FIX in vitro. Finally, we assessed the therapeutic efficacy of this approach in vivo using a mouse model of HB. CONCLUSIONS: Functional FIX, whose post-translational modifications only occur in fully mature hepatocytes, was only produced in corrected iPSCs differentiated in organoids. Immunohistochemistry analyses of mouse livers indicated a good cell engraftment, and the FIX activity detected in the plasma of transplanted animals confirmed rescue of the bleeding phenotype.


Assuntos
Hemofilia B , Células-Tronco Pluripotentes Induzidas , Fígado Artificial , Animais , Biomarcadores , Diferenciação Celular , Fator IX/genética , Hemofilia B/genética , Hemofilia B/terapia , Hepatócitos , Humanos
5.
Int J Mol Sci ; 23(18)2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36142774

RESUMO

The use of primary cells in human liver therapy is limited by a lack of cells. Induced pluripotent stem cells (iPSCs) represent an alternative to primary cells as they are infinitely expandable and can be differentiated into different liver cell types. The aim of our work was to demonstrate that simian iPSCs (siPSCs) could be used as a new source of liver cells to be used as a large animal model for preclinical studies. We first differentiated siPSCs into a homogenous population of hepatoblasts (siHBs). We then separately differentiated them into hepatocytes (siHeps) and cholangiocytes (siChols) expressing respective specific markers and displaying epithelial polarity. Moreover, we showed that polarized siChols can self-organize into 3D structures. These results should facilitate the deciphering of liver development and open the way to exploring co-culture systems that could be assessed during preclinical studies, including in autologous monkey donors, for regenerative medicine purposes.


Assuntos
Células-Tronco Pluripotentes Induzidas , Animais , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Células Epiteliais , Hepatócitos/metabolismo , Humanos , Fígado
6.
BMC Musculoskelet Disord ; 22(1): 698, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34399725

RESUMO

BACKGROUND: Management of talar fractures remains to be one of the most challenging aspects in trauma surgery. Unfortunately, the evidence regarding the correct treatment of these fractures is mainly based on retrospective case series, while studies assessing the patient-reported outcome are rare. Therefore, the aim of this trial was to analyze the patient reported outcome in context of trauma mechanism and concomitant injuries following operative treatment of talar fractures. METHODS: A retrospective outcome study of patients with operatively treated talar fractures between 2003 and 2015 was conducted. The fractures were classified according to AO-/Hawkins classification system and to the Marti-Weber classification. Data was collected via patient registry, radiographs and a validated patient-reported outcome measure (PROM) for foot and ankle pathologies (Foot and Ankle Outcome Score = FOAS). An analysis regarding the functional outcome, concomitant injury and timing of surgery using the nonparametric Mann-Whitney U test and Spearman`s rank correlation was performed. RESULTS: In total the functional outcome of 32 patients suffering from fractures to the talus were analyzed. The median age of the study cohort was 35±12.2 years, including 9 female (28 %) and 23 male (72 %) patients. The median FAOS score was 72±22.7 (range 13-94). Patients with an isolated talar fracture had an FAOS of 87±20 and with concomitant injury a score of 60±23.4 (p = 0.016). Patients with a closed talar fracture without emergency operation due to dislocation or polytrauma, showed no correlation between timing of surgery and FAOS (r= -0.17, p = 0.43). 10 % of the patients developed an avascular necrosis and 25 % showed signs of a posttraumatic arthritis. The follow-up time was 41 months (range: 16-145). CONCLUSIONS: Talar fractures were typically caused by high-energy trauma often associated with additional injuries of the lower extremity. The majority of the patients showed a fair to poor functional long-term outcome. Concomitant injuries of the lower extremity led to a lower FAOS. In closed talar fractures without the necessity of an emergency surgical intervention, time to surgery did not influence the patient reported outcome. Relating to the presented data, delayed surgery after soft tissue consolidation was not associated with a higher risk of developing an avascular necrosis.


Assuntos
Fraturas Ósseas , Tálus , Adulto , Feminino , Fixação Interna de Fraturas/efeitos adversos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Retrospectivos , Tálus/diagnóstico por imagem , Tálus/cirurgia , Resultado do Tratamento , Adulto Jovem
7.
World J Surg ; 41(3): 687-692, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27872974

RESUMO

BACKGROUND: The objective of this study was to evaluate the interest of using ropivacaine for outpatient laparoscopic cholecystectomy. The use of local anesthesia by instillation and infiltration could reduce pain and increase the number of outpatient cholecystectomies. METHODS: A one-center randomized prospective clinical trial compared the use of ropivacaine during outpatient laparoscopic cholecystectomy to the control group of outpatients for laparoscopic cholecystectomy between April 2014 and May 2015. One hundred twenty-four were eligible, and 100 patients were randomized. Patients with outpatient cholecystectomy were randomized into 2 groups: ropivacaine group (Rop group) and control group (control group). We performed a ropivacaine intraperitoneal instillation and wound infiltration for the ropivacaine group at the end of the procedure. The primary observation was authorization for home discharge. The patient was evaluated by the surgeon using the Chung score. Secondary observations included postoperative pain at 2 h post-surgery, at 6 h post-surgery and the day following surgery. RESULTS: Ninety-eight were able to leave on the evening of surgery. At 6 h post-surgery, the Chung score was identical for both groups (p = 0.73). At 2 and 6 h post-surgery and the day following surgery, there was no significant difference in pain levels (p = 0.63; p = 0.61; p = 0.98). Analgesic consumption was no significant difference in the groups. CONCLUSIONS: The use of ropivacaine does not increase the rate of home discharge and does not change the postoperative pain of outpatient cholecystectomy.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Amidas/uso terapêutico , Anestésicos Locais/uso terapêutico , Colecistectomia Laparoscópica , Dor Pós-Operatória/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Estudos Prospectivos , Ropivacaina
8.
J Hepatol ; 65(1): 182-199, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26916529

RESUMO

Orthotopic liver transplantation remains the only curative treatment for liver disease. However, the number of patients who die while on the waiting list (15%) has increased in recent years as a result of severe organ shortages; furthermore the incidence of liver disease is increasing worldwide. Clinical trials involving hepatocyte transplantation have provided encouraging results. However, transplanted cell function appears to often decline after several months, necessitating liver transplantation. The precise aetiology of the loss of cell function is not clear, but poor engraftment and immune-mediated loss appear to be important factors. Also, primary human hepatocytes (PHH) are not readily available, de-differentiate, and die rapidly in culture. Hepatocytes are available from other sources, such as tumour-derived human hepatocyte cell lines and immortalised human hepatocyte cell lines or porcine hepatocytes. However, all these cells suffer from various limitations such as reduced or differences in functions or risk of zoonotic infections. Due to their significant potential, one possible inexhaustible source of hepatocytes is through the directed differentiation of human induced pluripotent stem cells (hiPSCs). This review will discuss the potential applications and existing limitations of hiPSC-derived hepatocytes in regenerative medicine, drug screening, in vitro disease modelling and bioartificial livers.


Assuntos
Células-Tronco Pluripotentes Induzidas , Animais , Diferenciação Celular , Hepatócitos , Humanos , Fígado Artificial , Medicina Regenerativa
9.
Gesnerus ; 73(2): 256-72, 2016.
Artigo em Alemão | MEDLINE | ID: mdl-29470017

RESUMO

Ornithology has emerged as a science at the turn of the 18th century. To become a self-sufficient scientific discipline, studies of birds had to distinguish themselves from luxury, trade and poetry. Scholars had to invent new ways of writing, different from the beautiful and ornamented books on birds, even if these books were often published by other scholars who had been expelled from academic institutions and therefore considered as «amateurs¼. The same scholars needed the help of «amateurs¼ in order to observe and explain bird migration. First ornithological discourses in Europe and the United States illustrate the relationships between scholars, authors and «amateurs¼ and show how these words can be used in different meanings.

10.
Hepatology ; 60(2): 700-14, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24715669

RESUMO

UNLABELLED: Cholangiocytes are biliary epithelial cells, which, like hepatocytes, originate from hepatoblasts during embryonic development. In this study we investigated the potential of human embryonic stem cells (hESCs) to differentiate into cholangiocytes and we report a new approach, which drives differentiation of hESCs toward the cholangiocytic lineage using feeder-free and defined culture conditions. After differentiation into hepatic progenitors, hESCs were differentiated further into cholangiocytes using growth hormone, epidermal growth factor, interleukin-6, and then sodium taurocholate. These conditions also allowed us to generate cholangiocytes from HepaRG-derived hepatoblasts. hESC- and HepaRG-derived cholangiocyte-like cells expressed markers of cholangiocytes including cytokeratin 7 and osteopontin, and the transcription factors SOX9 and hepatocyte nuclear factor 6. The cells also displayed specific proteins important for cholangiocyte functions including cystic fibrosis transmembrane conductance regulator, secretin receptor, and nuclear receptors. They formed primary cilia and also responded to hormonal stimulation by increase of intracellular Ca(2+) . We demonstrated by integrative genomics that the expression of genes, which signed hESC- or HepaRG-cholangiocytes, separates hepatocytic lineage from cholangiocyte lineage. When grown in a 3D matrix, cholangiocytes developed epithelial/apicobasal polarity and formed functional cysts and biliary ducts. In addition, we showed that cholangiocyte-like cells could also be generated from human induced pluripotent stem cells, demonstrating the efficacy of our approach with stem/progenitor cells of diverse origins. CONCLUSION: We have developed a robust and efficient method for differentiating pluripotent stem cells into cholangiocyte-like cells, which display structural and functional similarities to bile duct cells in normal liver. These cells will be useful for the in vitro study of the molecular mechanisms of bile duct development and have important potential for therapeutic strategies, including bioengineered liver approaches.


Assuntos
Sistema Biliar/citologia , Técnicas de Cultura de Células/métodos , Células-Tronco Embrionárias/citologia , Células Epiteliais/citologia , Hepatócitos/citologia , Células-Tronco Pluripotentes/citologia , Biomarcadores , Diferenciação Celular , Linhagem da Célula , Polaridade Celular , Células Cultivadas , Colagogos e Coleréticos/farmacologia , Meios de Cultura/farmacologia , Hormônio do Crescimento Humano/farmacologia , Humanos , Interleucina-6/farmacologia , Ácido Taurocólico/farmacologia , Transcriptoma
12.
BMC Biol ; 11: 86, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23870169

RESUMO

BACKGROUND: Human pluripotent stem cells (hPSCs) hold great promise for applications in regenerative medicine. However, the safety of cell therapy using differentiated hPSC derivatives must be improved through methods that will permit the transplantation of homogenous populations of a specific cell type. To date, purification of progenitors and mature cells generated from either embryonic or induced pluripotent stem cells remains challenging with use of conventional methods. RESULTS: We used lentivectors encoding green fluorescent protein (GFP) driven by the liver-specific apoliprotein A-II (APOA-II) promoter to purify human hepatic progenitors. We evaluated both integrating and integration-defective lentivectors in combination with an HIV integrase inhibitor. A human embryonic stem cell line was differentiated into hepatic progenitors using a chemically defined protocol. Subsequently, cells were transduced and sorted at day 16 of differentiation to obtain a cell population enriched in hepatic progenitor cells. After sorting, more than 99% of these APOA-II-GFP-positive cells expressed hepatoblast markers such as α-fetoprotein and cytokeratin 19. When further cultured for 16 days, these cells underwent differentiation into more mature cells and exhibited hepatocyte properties such as albumin secretion. Moreover, they were devoid of vector DNA integration. CONCLUSIONS: We have developed an effective strategy to purify human hepatic cells from cultures of differentiating hPSCs, producing a novel tool that could be used not only for cell therapy but also for in vitro applications such as drug screening. The present strategy should also be suitable for the purification of a broad range of cell types derived from either pluripotent or adult stem cells.


Assuntos
Diferenciação Celular , Separação Celular/métodos , Células-Tronco Embrionárias/citologia , Vetores Genéticos/genética , Hepatócitos/citologia , Lentivirus/genética , Integração Viral/fisiologia , Apolipoproteína A-II/genética , Biomarcadores/metabolismo , Linhagem Celular , Citocromo P-450 CYP3A/metabolismo , DNA Viral/metabolismo , Citometria de Fluxo , Genes Reporter , Proteínas de Fluorescência Verde/metabolismo , Hepatócitos/metabolismo , Humanos , Fígado/citologia , Especificidade de Órgãos , Regiões Promotoras Genéticas/genética , Transdução Genética
13.
Front Psychiatry ; 15: 1421582, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39415892

RESUMO

Background: Existing literature on moral conflicts that healthcare professionals encounter in dementia care has explored, amongst others, issues related to autonomy, decision-making capacity, privacy, and more. Notably, conflicts related to healthcare professionals who support informal dementia caregiving and who are confronted with family members being overburdened with their care responsibly remains an underexplored topic in the current literature, particularly in the context of Low-and Middle-Income Countries. The present paper introduces such an encounter, presenting an ethical case analysis of a conflict that occurred during a larger research project conducted in North Macedonia. Case to be studied: Due to the absence of formal care services that could have relieved an overburdened family caregiver, healthcare professionals felt compelled to reach out to the uninvolved adult daughters, requesting them to participate in their parents' care. Wondering about whether their reaching out to the daughters might count as an attempt of pressure and undue interference, professionals conflicted over the appropriateness of their action. This paper follows up on their concern, ethically assessing the professionals' action. To answer the question on whether the healthcare professionals acted appropriately or not, and to what extent, theories of filial duties are applied, embedding their action in the larger context of dementia care in North Macedonia. Results and conclusion: It is argued that the lack of formal care services in North Macedonia is of utmost relevance to the conflict. Thus, the conclusion is that the ethical inappropriateness of the case is to be located not so much with the action of the healthcare professionals but with the state because of its failure to provide professional care services that allow healthcare professionals to take ethically sound actions to counteract overarching burdens that family members face when providing informal dementia care.

14.
RMD Open ; 10(2)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749532

RESUMO

OBJECTIVES: To investigate lectin pathway proteins (LPPs) as biomarkers for axial spondyloarthritis (axSpA) in a cross-sectional cohort with a suspicion of axSpA, comprising newly diagnosed axSpA and chronic low back pain (cLBP) individuals. METHODS: Serum samples from 515 participants within the OptiRef cohort, including 151 axSpA patients and 364 cLBP patients, were measured using immunoassays for LPPs (mannan-binding lectin (MBL), collectin liver-1 (CL-L1), M-ficolin, H-ficolin and L-ficolin, MBL-associated serine proteases (MASP)-1, -2 and -3, MBL-associated proteins (MAp19 and MAp44) and the complement activation product C3dg). RESULTS: Serum levels of L-ficolin, MASP-2 and C3dg were elevated in axSpA patients, whereas levels of MASP-3 and CL-L1 were decreased, and this remained significant for C3dg and MASP-3 after adjustment for C reactive protein (CRP). A univariate regression analysis showed serum levels of CL-L1, MASP-2, MASP-3 and C3dg to predict the diagnosis of axSpA, and MASP-3 and C3dg remained significant in a multivariate logistic regression analysis. Assessment of the diagnostic potential showed that a combination of human leukocyte antigen B27 (HLA-B27) and measurements of L-ficolin, MASP-3 and C3dg increased the diagnostic specificity for axSpA, however, with a concomitant loss of sensitivity. CONCLUSIONS: Serum levels of complement activation, that is, C3dg, and MASP-3 differed significantly between axSpA and cLBP patients after adjustment for CRP. Although combining HLA-B27 with measurements of L-ficolin, MASP-3 and C3dg increased the diagnostic specificity for axSpA, this seems unjustified due to the concomitant loss of sensitivity. However, both C3dg and MASP-3 were associated with axSpA diagnosis in multivariate logistic regression, suggesting an involvement of complement in the inflammatory processes and possibly pathogenesis in axSpA.


Assuntos
Espondiloartrite Axial , Biomarcadores , Proteínas do Sistema Complemento , Humanos , Biomarcadores/sangue , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Estudos Transversais , Proteínas do Sistema Complemento/metabolismo , Proteínas do Sistema Complemento/análise , Espondiloartrite Axial/diagnóstico , Espondiloartrite Axial/sangue , Espondiloartrite Axial/etiologia , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Lectinas/sangue , Ativação do Complemento
15.
Elife ; 112022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35195068

RESUMO

In multicellular organisms, the specification, coordination, and compartmentalization of cell types enable the formation of complex body plans. However, some eukaryotic protists such as slime molds generate diverse and complex structures while remaining in a multinucleate syncytial state. It is unknown if different regions of these giant syncytial cells have distinct transcriptional responses to environmental encounters and if nuclei within the cell diversify into heterogeneous states. Here, we performed spatial transcriptome analysis of the slime mold Physarum polycephalum in the plasmodium state under different environmental conditions and used single-nucleus RNA-sequencing to dissect gene expression heterogeneity among nuclei. Our data identifies transcriptome regionality in the organism that associates with proliferation, syncytial substructures, and localized environmental conditions. Further, we find that nuclei are heterogenous in their transcriptional profile and may process local signals within the plasmodium to coordinate cell growth, metabolism, and reproduction. To understand how nuclei variation within the syncytium compares to heterogeneity in single-nucleus cells, we analyzed states in single Physarum amoebal cells. We observed amoebal cell states at different stages of mitosis and meiosis, and identified cytokinetic features that are specific to nuclei divisions within the syncytium. Notably, we do not find evidence for predefined transcriptomic states in the amoebae that are observed in the syncytium. Our data shows that a single-celled slime mold can control its gene expression in a region-specific manner while lacking cellular compartmentalization and suggests that nuclei are mobile processors facilitating local specialized functions. More broadly, slime molds offer the extraordinary opportunity to explore how organisms can evolve regulatory mechanisms to divide labor, specialize, balance competition with cooperation, and perform other foundational principles that govern the logic of life.


Assuntos
Células Gigantes/fisiologia , Physarum polycephalum/metabolismo , Análise de Célula Única , Transcriptoma , Regulação da Expressão Gênica , RNA-Seq
16.
Hepatology ; 51(5): 1754-65, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20301097

RESUMO

UNLABELLED: Generation of hepatocytes from human embryonic stem cells (hESCs) could represent an advantageous source of cells for cell therapy approaches as an alternative to orthotopic liver transplantation. However, the generation of differentiated hepatocytes from hESCs remains a major challenge, especially using a method compatible with clinical applications. We report a novel approach to differentiate hESCs into functional hepatic cells using fully defined culture conditions, which recapitulate essential stages of liver development. hESCs were first differentiated into a homogenous population of endoderm cells using a combination of activin, fibroblast growth factor 2, and bone morphogenetic protein 4 together with phosphoinositide 3-kinase inhibition. The endoderm cells were then induced to differentiate further into hepatic progenitors using fibroblast growth factor 10, retinoic acid, and an inhibitor of activin/nodal receptor. After further maturation, these cells expressed markers of mature hepatocytes, including asialoglycoprotein receptor, tyrosine aminotransferase, alpha1-antitrypsin, Cyp7A1, and hepatic transcription factors such as hepatocyte nuclear factors 4alpha and 6. Furthermore, the cells generated under these conditions exhibited hepatic functions in vitro, including glycogen storage, cytochrome activity, and low-density lipoprotein uptake. After transduction with a green fluorescent protein-expressing lentivector and transplantation into immunodeficient uPA transgenic mice, differentiated cells engrafted into the liver, grew, and expressed human albumin and alpha1-antitrypsin as well as green fluorescent protein for at least 8 weeks. In addition, we showed that hepatic cells could be generated from human-induced pluripotent cells derived from reprogrammed fibroblasts, demonstrating the efficacy of this approach with pluripotent stem cells of diverse origins. CONCLUSION: We have developed a robust and efficient method to differentiate pluripotent stem cells into hepatic cells, which exhibit characteristics of human hepatocytes. Our approach should facilitate the development of clinical grade hepatocytes for transplantation and for research on drug discovery.


Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/citologia , Hepatócitos/citologia , Fígado/embriologia , Ativinas/farmacologia , Animais , Benzamidas/farmacologia , Proteína Morfogenética Óssea 4/farmacologia , Diferenciação Celular/fisiologia , Cromonas/farmacologia , Dioxóis/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Camundongos , Morfolinas/farmacologia , Células-Tronco Pluripotentes/citologia , Tretinoína/farmacologia
17.
Am J Obstet Gynecol ; 205(1): 69.e1-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21545996

RESUMO

OBJECTIVE: The purpose of this study was to reanalyze the results of a previously published trial that compared 3 methods of anterior colporrhaphy according to the clinically relevant definitions of success. STUDY DESIGN: A secondary analysis of a trial of 114 subjects who underwent surgery for anterior pelvic organ prolapse who were assigned randomly to standard anterior colporrhaphy, ultralateral colporrhaphy, or anterior colporrhaphy plus polyglactin 910 mesh from 1996-1999. For the current analysis, success was defined as (1) no prolapse beyond the hymen, (2) the absence of prolapse symptoms (visual analog scale ≤ 2), and (3) the absence of retreatment. RESULTS: Eighty-eight percent of the women met our definition of success at 1 year. One subject (1%) underwent surgery for recurrence 29 months after surgery. No differences among the 3 groups were noted for any outcomes. CONCLUSION: Reanalysis of a trial of 3 methods of anterior colporrhaphy revealed considerably better success with the use of clinically relevant outcome criteria compared with strict anatomic criteria.


Assuntos
Procedimentos Cirúrgicos em Ginecologia , Prolapso de Órgão Pélvico/cirurgia , Vagina/cirurgia , Idoso , Feminino , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Pessoa de Meia-Idade , Poliglactina 910/uso terapêutico , Recidiva , Resultado do Tratamento
18.
Forensic Sci Int ; 325: 110872, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34147938

RESUMO

Silicone embolism syndrome (SES) is a well known complication after injection of silicone gel as well as liquid silicone. Rarely, men use physiologic salt solution or liquid silicone injected into the subcutaneous tissue of the scrotum, the penis, the upper genital or the inguinal region. Those men, who call themselves "siliconers", want to get a larger penis and scrotum, also visible when wearing clothes. Injections of liquid silicone in the mentioned regions can lead to liquid silicone embolism in the lungs and also the liver, sometimes eventually leading to death via right heart failure as in the present case. Autopsy revealed "frog spawn"-like vacuoles in the subcutaneous tissue of the genital region and liquid silicone embolism in lungs and liver. Additionally, toxicological analyses revealed different liquid silicones. Smaller oligomers were transported into lung and liver, larger ones showed local enrichment at the injection site. The seized Polydimethylsiloxane (PDMS) could not be detected in abdominal fat, blood or urine, potentially due to low perfusion of fat tissue, the aqueous character of blood and urine or the time span between last injection and death.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/patologia , Embolia/induzido quimicamente , Embolia Pulmonar/induzido quimicamente , Silicones/efeitos adversos , Adulto , Transtornos Dismórficos Corporais/complicações , Embolia/patologia , Humanos , Injeções Subcutâneas , Fígado/patologia , Pulmão/patologia , Masculino , Embolia Pulmonar/patologia , Vacúolos
19.
Hepatology ; 49(3): 950-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19152424

RESUMO

UNLABELLED: The feasibility of ex vivo gene therapy as an alternative to liver transplantation for the treatment of liver metabolic diseases needs to be analyzed in large animal models. This approach requires appropriate gene transfer vectors and effective hepatocyte engraftment. Lentiviral vectors have the ability to transduce nondividing differentiated cells, such as hepatocytes, and portal vein occlusion increases hepatocyte engraftment. We investigated whether reversible portal vein embolization combined with ex vivo lentivirus-mediated gene transfer is an effective approach for successful hepatocyte engraftment in nonhuman primates and whether the transgene remains expressed in the long term in transplanted hepatocytes in situ. Simian hepatocytes were isolated after left lobe resection, and the left and right anterior portal branches of animals were embolized with absorbable material. Isolated hepatocytes were labeled with Hoechst dye or transduced in suspension with lentiviruses expressing green fluorescent protein under the control of the human apolipoprotein A-II promoter and transplanted via the inferior mesenteric vein. The whole procedure was well tolerated. The embolized liver was revascularized within 2 weeks. The volume of nonembolized liver increased from 38.7% +/- 0.8% before embolization to 55.9% +/- 1% after embolization and hepatocytes significantly proliferated (10.5% +/- 0.4% on day 3 after embolization). Liver repopulation after transplantation with Hoechst-labeled hepatocytes was 7.4% +/- 1.2%. Liver repopulation was 2.1% +/- 0.2% with transduced hepatocytes, a proportion similar to that obtained with Hoechst-labeled cells, given that the mean transduction efficacy of simian hepatocyte population was 34%. Transgene expression persisted at 16 weeks after transplantation. CONCLUSION: We have developed a new approach to improve hepatocyte engraftment and to express a transgene in the long term in nonhuman primates. This strategy could be suitable for clinical applications.


Assuntos
Apolipoproteína A-II/metabolismo , Transplante de Células/métodos , Embolização Terapêutica/métodos , Hepatócitos/metabolismo , Hepatócitos/transplante , Animais , Apolipoproteína A-II/genética , Proliferação de Células , Regulação da Expressão Gênica , Terapia Genética , Hepatócitos/patologia , Humanos , Lentivirus/genética , Fígado/metabolismo , Fígado/patologia , Fígado/cirurgia , Regeneração Hepática/fisiologia , Macaca mulatta , Modelos Animais , Veia Porta/cirurgia , Transgenes/genética
20.
Stem Cells ; 27(11): 2655-66, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19688839

RESUMO

Human pluripotent stem cells from embryonic origins and those generated from reprogrammed somatic cells share many characteristics, including indefinite proliferation and a sustained capacity to differentiate into a wide variety of cell types. However, it remains to be demonstrated whether both cell types rely on similar mechanisms to maintain their pluripotent status and to control their differentiation. Any differences in such mechanisms would suggest that reprogramming of fibroblasts to generate induced pluripotent stem cells (iPSCs) results in novel states of pluripotency. In that event, current methods for expanding and differentiating human embryonic stem cells (ESCs) might not be directly applicable to human iPSCs. However, we show here that human iPSCs rely on activin/nodal signaling to control Nanog expression and thereby maintain pluripotency, thus revealing their mechanistic similarity to human ESCs. We also show that growth factors necessary and sufficient for achieving specification of human ESCs into extraembryonic tissues, neuroectoderm, and mesendoderm also drive differentiation of human iPSCs into the same tissues. Importantly, these experiments were performed in fully chemically defined medium devoid of factors that could obscure analysis of developmental mechanisms or render the resulting tissues incompatible with future clinical applications. Together these data reveal that human iPSCs rely on mechanisms similar to human ESCs to maintain their pluripotency and to control their differentiation, showing that these pluripotent cell types are functionally equivalent.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Transdução de Sinais/fisiologia , Receptores de Ativinas/antagonistas & inibidores , Ativinas/farmacologia , Adulto , Animais , Benzamidas/farmacologia , Proteína Morfogenética Óssea 4/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Células Cultivadas , Meios de Cultura , Dioxóis/farmacologia , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Feminino , Fator 2 de Crescimento de Fibroblastos/farmacologia , Fibroblastos/citologia , Citometria de Fluxo , Imunofluorescência , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator 4 Semelhante a Kruppel , Fatores de Transcrição Kruppel-Like/genética , Fatores de Transcrição Kruppel-Like/fisiologia , Masculino , Camundongos , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/fisiologia , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/fisiologia , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
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