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1.
Nat Biomed Eng ; 5(8): 926-940, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34373601

RESUMO

Current protocols for the differentiation of human pluripotent stem cells (hPSCs) into chondrocytes do not allow for the expansion of intermediate progenitors so as to prospectively assess their chondrogenic potential. Here we report a protocol that leverages PRRX1-tdTomato reporter hPSCs for the selective induction of expandable and ontogenetically defined PRRX1+ limb-bud-like mesenchymal cells under defined xeno-free conditions, and the prospective assessment of the cells' chondrogenic potential via the cell-surface markers CD90, CD140B and CD82. The cells, which proliferated stably and exhibited the potential to undergo chondrogenic differentiation, formed hyaline cartilaginous-like tissue commensurate to their PRRX1-expression levels. Moreover, we show that limb-bud-like mesenchymal cells derived from patient-derived induced hPSCs can be used to identify therapeutic candidates for type II collagenopathy and we developed a method to generate uniformly sized hyaline cartilaginous-like particles by plating the cells on culture dishes coated with spots of a zwitterionic polymer. PRRX1+ limb-bud-like mesenchymal cells could facilitate the mass production of chondrocytes and cartilaginous tissues for applications in drug screening and tissue engineering.


Assuntos
Proteínas de Homeodomínio/genética , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Pluripotentes/citologia , Animais , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Condrócitos/citologia , Condrócitos/metabolismo , Condrócitos/transplante , Condrogênese , Doenças do Colágeno/terapia , Meios de Cultura/química , Proteínas de Homeodomínio/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Células-Tronco Pluripotentes/metabolismo , Polímeros/química , Receptor beta de Fator de Crescimento Derivado de Plaquetas/metabolismo , Antígenos Thy-1/metabolismo , Engenharia Tecidual
2.
Circ Rep ; 3(4): 256-257, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33842732
3.
Zoolog Sci ; 38(2): 122-139, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33812352

RESUMO

We focused on Meloe beetles that have lost all flight ability, and conducted molecular phylogeographic analyses based on their mitochondrial DNA COI and nuclear DNA EF1- α regions. Meloe beetles infiltrate bumblebee nests by attaching to bumblebees as they pollinate flowers and thereafter have a unique and specific life history as they complete their life-cycle within the host nest; flight-based dispersal is achieved by piggybacking on bumblebees. In fact, Meloe beetles, which cannot fly, even inhabit remote islands (i.e., "Oceanic Islands"). Regarding four species, i.e., Meloe coarctatus, Meloe proscarabaeus, Meloe violaceus and Meloe corvinus, the conventional morphological classification system based on morphological characteristics was strongly supported by the molecular markers. On the other hand, for two species, Meloe menoko and Meloe auriculatus, it was found that M. menoko may be evaluated as having a paraphyletic relationship with M. auriculatus. Furthermore, two other cryptic, undescribed species were also discovered in this study. One was collected in the Nikko Highland, and inhabited the area sympatrically with M. coarctatus. The other was collected from Hachijo-jima Island. These cryptic species were highly differentiated, independent lineages in terms of mitochondrial and nuclear gene regions. That is to say, a new level of species diversity was revealed among the Meloe beetle species, known for their unique and strange ecological and ethological characteristics.


Assuntos
Distribuição Animal , Abelhas/parasitologia , Besouros/fisiologia , Voo Animal , Fluxo Gênico , Animais , Besouros/genética , DNA Mitocondrial , Interações Hospedeiro-Parasita , Filogenia , Especificidade da Espécie
6.
Stem Cells Transl Med ; 10(1): 115-127, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32822104

RESUMO

Human induced pluripotent stem cells (hiPSCs) are a promising cell source for the creation of cartilage to treat articular cartilage damage. The molecular mechanisms that translate culture conditions to the chondrogenic differentiation of hiPSCs remain to be analyzed. To analyze the effects of culture substrates, we chondrogenically differentiated hiPSCs on Matrigel or laminin 511-E8 while holding the composition of the chondrogenic medium constant. Cartilage was formed from hiPSCs on Matrigel, but not on laminin 511-E8. On Matrigel, the hiPSCs were round and yes-associated protein (YAP) was inactive. In contrast, on laminin 511-E8, the hiPSCs were flat and YAP was active. Treating the laminin 511-E8 hiPSCs in a bioreactor caused cell aggregates, in which the cells were round and YAP was inactive. Subsequent culture of the aggregates in chondrogenic medium resulted in cartilage formation. Transient knockdown of YAP in hiPSCs around the start of chondrogenic differentiation successfully formed cartilage on laminin 511-E8, suggesting that the activation of YAP is responsible for the failure of cartilage formation from hiPSCs on laminin 511-E8. Consistently, the addition of YAP inhibitors to laminin 511-E8 hiPSCs caused partial cartilage formation. This study contributes to identifying the molecules that mediate the effects of culture substrates on the chondrogenic differentiation of hiPSCs as well as to developing clinically applicable chondrogenic differentiation methods.

7.
Cell Mol Immunol ; 18(3): 523-527, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32868910

RESUMO

The interactions of CD4+ T cells and B cells are fundamental for the generation of protective antibody responses, as well as for the development of harmful autoimmune diseases. Recent studies of human tissues and blood samples have established a new subset of CD4+ B helper T cells named peripheral helper T (Tph) cells. Unlike T follicular helper (Tfh) cells, which interact with B cells within lymphoid organs, Tph cells provide help to B cells within inflamed tissues. Tph cells share many B helper-associated functions with Tfh cells and induce B cell differentiation toward antibody-producing cells. The differentiation mechanism is also partly shared between Tph and Tfh cells in humans, and both Tfh and Tph cells can be found within the same tissues, including cancer tissues. However, Tph cells display features distinct from those of Tfh cells, such as the expression of chemokine receptors associated with Tph cell localization within inflamed tissues and a low Bcl-6/Blimp1 ratio. Unlike that of Tfh cells, current evidence shows that the target of Tph cells is limited to memory B cells. In this review, we first summarize recent findings on human Tph cells and discuss how Tph and Tfh cells play shared and distinct roles in human diseases.

9.
J Orthop Res ; 39(2): 449-457, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33325059

RESUMO

Treatment of implant-associated orthopedic infections remains challenging, partly because antimicrobial treatment is ineffective after a mature biofilm covers the implant surface. Currently, the relative efficacy of systemic mono- and combination standard-of-care (SOC) antibiotic therapies over the course of mature biofilm formation is unknown. Thus, we assessed the effects of cefazoline (CEZ), gentamicin (GM), and vancomycin, with or without rifampin (RFP), on Staphylococcus aureus biofilm formation during the establishment of implant-associated osteomyelitis in a murine tibia model. Quantitative scanning electron microscopy of the implants harvested on Days 0, 3, and 7 revealed that all treatments except CEZ monotherapy significantly reduced biofilm formation when antibiotics started at Day 0 (0.46- to 0.25-fold; p < 0.05). When antibiotics commenced 3 days after the infection, only GM monotherapy significantly inhibited biofilm growth (0.63-fold; p < 0.05), while all antibiotics inhibited biofilm formation in combination with RFP (0.56- to 0.44-fold; p < 0.05). However, no treatment was effective when antibiotics commenced on Day 7. To confirm these findings, we assessed bacterial load via colony-forming unit and histology. The results showed that GM monotherapy and all combination therapies reduced the colony-forming unit in the implant (0.41- to 0.23-fold; p < 0.05); all treatments except CEZ monotherapy reduced the colony-forming unit and staphylococcus abscess communities in the tibiae (0.40- to 0.10-fold; p < 0.05). Collectively, these findings demonstrate that systemic SOC antibiotics can inhibit biofilm formation within 3 days but not after 7 days of infection. The efficacy of SOC monotherapies, CEZ particularly, is very limited. Thus, combination treatment with RFP may be necessary to inhibit implant-associated osteomyelitis.


Assuntos
Antibacterianos/uso terapêutico , Cefazolina/uso terapêutico , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Osteomielite/tratamento farmacológico , Infecções Relacionadas à Prótese/tratamento farmacológico , Animais , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/ultraestrutura , Cefazolina/farmacologia , Modelos Animais de Doenças , Quimioterapia Combinada , Feminino , Camundongos Endogâmicos BALB C , Osteomielite/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Staphylococcus aureus , Falha de Tratamento
10.
Sci Rep ; 10(1): 20787, 2020 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-33247195

RESUMO

Post-traumatic osteoarthritis (PTOA) is a major cause which hinders patients from the recovery after intra-articular injuries or surgeries. Currently, no effective treatment is available. In this study, we showed that inhibition of the acute stage chondrocyte death is a promising strategy to mitigate the development of PTOA. Namely, we examined efficacies of Kyoto University Substance (KUS) 121, a valosin-containing protein modulator, for PTOA as well as its therapeutic mechanisms. In vivo, in a rat PTOA model by cyclic compressive loading, intra-articular treatments of KUS121 significantly improved the modified Mankin scores and reduced damaged-cartilage volumes, as compared to vehicle treatment. Moreover, KUS121 markedly reduced the numbers of TUNEL-, CHOP-, MMP-13-, and ADAMTS-5-positive chondrocytes in the damaged knees. In vitro, KUS121 rescued human articular chondrocytes from tunicamycin-induced cell death, in both monolayer culture and cartilage explants. It also significantly downregulated the protein or gene expression of ER stress markers, proinflammatory cytokines, and extracellular-matrix-degrading enzymes induced by tunicamycin or IL-1ß. Collectively, these results demonstrated that KUS121 protected chondrocytes from cell death through the inhibition of excessive ER stress. Therefore, KUS121 would be a new, promising therapeutic agent with a protective effect on the progression of PTOA.


Assuntos
Naftalenos/uso terapêutico , Osteoartrite/tratamento farmacológico , Piridinas/uso terapêutico , Ácidos Sulfônicos/uso terapêutico , Proteína com Valosina/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Idoso , Animais , Apoptose/efeitos dos fármacos , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/lesões , Cartilagem Articular/metabolismo , Células Cultivadas , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo , Condrócitos/patologia , Citocinas/genética , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Masculino , Osteoartrite/etiologia , Osteoartrite/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Tunicamicina/toxicidade , Ferimentos e Lesões/complicações
11.
J Cardiol Cases ; 22(4): 170-173, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33014198

RESUMO

Unicuspid aortic valve (UAV) is an extremely rare congenital malformation that frequently presents with valvular dysfunction or aortic aneurysm. Here we report the case of a 49-year-old man with severe aortic stenosis caused by UAV requiring the Bentall procedure. Two- and three-dimensional transesophageal echocardiography revealed an eccentric opening in an aortic valve and a lateral attachment to the aorta at the orifice level, suggestive of which is consistent with unicommissural UAV as confirmed by surgical findings. .

12.
Int Cancer Conf J ; 9(4): 207-211, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32904147

RESUMO

The dose-dense epirubicin and cyclophosphamide (EC) therapy for breast cancer decreases the risk of cancer recurrence and death. However, epirubicin and cyclophosphamide also cause cardiotoxicity, and cardiomyopathy is the most well-known related adverse effect. A 58-year-old woman presented to our hospital with palpitations 2 weeks after her final dose-dense EC therapy for breast cancer. Holter electrocardiogram (ECG) showed transitory complete atrioventricular block (CAVB) and torsade de pointes. A 12-lead ECG showed QT prolongation in addition to CAVB. Patients receiving dose-dense EC therapy should be monitored more carefully with ECG due to their risk of fatal arrhythmias.

13.
Immunol Med ; 43(4): 156-160, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32584200

RESUMO

CXCL13-producing PD-1hiCXCR5-CD4+ T cells were discovered in synovial tissues of rheumatoid arthritis (RA). Further intensive analysis of RA samples led to the proposal of PD-1hiCXCR5-CD4+ T cells as a pathogenic CD4 subset, peripheral helper T (Tph) cells. Tph cells are upregulated also in the peripheral blood of seropositive RA patient and exert B-cell helper activities. Furthermore, Tph cells are associated with other inflammatory conditions including systemic lupus erythematosus, IgG4-related diseases, type 1 diabetes, inflammatory bowel diseases, and malignant tumors. In this review, molecular feature and pathogenic and beneficial functions of Tph cells in inflammatory conditions are discussed.


Assuntos
Artrite Reumatoide/imunologia , Quimiocina CXCL13/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Receptor de Morte Celular Programada 1 , Receptores CXCR5 , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T CD4-Positivos , Doença Crônica , Diabetes Mellitus Tipo 1/imunologia , Humanos , Doença Relacionada a Imunoglobulina G4/imunologia , Inflamação , Neoplasias/imunologia , Membrana Sinovial/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo
14.
Zookeys ; 933: 107-123, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508491

RESUMO

Podonychus gyobu sp. nov., a second species of the genus Podonychus Jäch & Kodada, 1997, hitherto known only from Indonesia, is described from Kyushu, Japan. This new species is similar to P. sagittarius Jäch & Kodada, 1997, but differs from it in the straight penis, arcuate 2nd labial palpomere, and in the 3rd antennomere being longer than wide. The endophallic structures and the larva of P. gyobu sp. nov. are described. A character matrix of the Macronychini genera and a key to the Japanese genera are provided.

15.
Orphanet J Rare Dis ; 15(1): 122, 2020 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-32448372

RESUMO

BACKGROUND: Fibrodysplasia ossificans progressiva (FOP) is a rare autosomal-dominant disease characterized by heterotopic ossification (HO) in soft tissues and caused by a mutation of the ACVR1A/ALK2 gene. Activin-A is a key molecule for initiating the process of HO via the activation of mTOR, while rapamycin, an mTOR inhibitor, effectively inhibits the Activin-A-induced HO. However, few reports have verified the effect of rapamycin on FOP in clinical perspectives. METHODS: We investigated the effect of rapamycin for different clinical situations by using mice conditionally expressing human mutant ACVR1A/ALK2 gene. We also compared the effect of rapamycin between early and episode-initiated treatments for each situation. RESULTS: Continuous, episode-independent administration of rapamycin reduced the incidence and severity of HO in the natural course of FOP mice. Pinch-injury induced HO not only at the injured sites, but also in the contralateral limbs and provoked a prolonged production of Activin-A in inflammatory cells. Although both early and injury-initiated treatment of rapamycin suppressed HO in the injured sites, the former was more effective at preventing HO in the contralateral limbs. Rapamycin was also effective at reducing the volume of recurrent HO after the surgical resection of injury-induced HO, for which the early treatment was more effective. CONCLUSION: Our study suggested that prophylactic treatment will be a choice of method for the clinical application of rapamycin for FOP.


Assuntos
Miosite Ossificante , Ossificação Heterotópica , Receptores de Ativinas Tipo I/genética , Animais , Humanos , Camundongos , Mutação , Miosite Ossificante/tratamento farmacológico , Miosite Ossificante/genética , Ossificação Heterotópica/tratamento farmacológico , Ossificação Heterotópica/genética , Sirolimo/farmacologia , Sirolimo/uso terapêutico
17.
Nature ; 580(7801): 124-129, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32238941

RESUMO

Pluripotent stem cells are increasingly used to model different aspects of embryogenesis and organ formation1. Despite recent advances in in vitro induction of major mesodermal lineages and cell types2,3, experimental model systems that can recapitulate more complex features of human mesoderm development and patterning are largely missing. Here we used induced pluripotent stem cells for the stepwise in vitro induction of presomitic mesoderm and its derivatives to model distinct aspects of human somitogenesis. We focused initially on modelling the human segmentation clock, a major biological concept believed to underlie the rhythmic and controlled emergence of somites, which give rise to the segmental pattern of the vertebrate axial skeleton. We observed oscillatory expression of core segmentation clock genes, including HES7 and DKK1, determined the period of the human segmentation clock to be around five hours, and demonstrated the presence of dynamic travelling-wave-like gene expression in in vitro-induced human presomitic mesoderm. Furthermore, we identified and compared oscillatory genes in human and mouse presomitic mesoderm derived from pluripotent stem cells, which revealed species-specific and shared molecular components and pathways associated with the putative mouse and human segmentation clocks. Using CRISPR-Cas9-based genome editing technology, we then targeted genes for which mutations in patients with segmentation defects of the vertebrae, such as spondylocostal dysostosis, have been reported (HES7, LFNG, DLL3 and MESP2). Subsequent analysis of patient-like and patient-derived induced pluripotent stem cells revealed gene-specific alterations in oscillation, synchronization or differentiation properties. Our findings provide insights into the human segmentation clock as well as diseases associated with human axial skeletogenesis.


Assuntos
Relógios Biológicos/fisiologia , Desenvolvimento Embrionário/fisiologia , Células-Tronco Pluripotentes/citologia , Somitos/citologia , Somitos/crescimento & desenvolvimento , Anormalidades Múltiplas/genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Relógios Biológicos/genética , Desenvolvimento Embrionário/genética , Edição de Genes , Regulação da Expressão Gênica no Desenvolvimento/genética , Glicosiltransferases/deficiência , Glicosiltransferases/genética , Hérnia Diafragmática/genética , Humanos , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Camundongos , Fenótipo , Somitos/metabolismo , Fatores de Tempo
19.
J Clin Rheumatol ; 26(7): 295-300, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31397763

RESUMO

OBJECTIVE: The aim of this longitudinal study was to examine the clinical significance of soluble lectin-like oxidized low-density lipoprotein receptor 1 (sLOX-1) in patients with rheumatoid arthritis. METHODS: We gathered demographic and clinical data for a large rheumatoid arthritis cohort at 3 time points. Blood samples were collected at each time point; the number of samples was 282 cases in 2012, 431 cases in 2013, and 500 cases in 2014. Plasma sLOX-1 was measured by enzyme-linked immunosorbent assay. Correlations between sLOX-1 and clinical data were analyzed. Predictive factors associated with changes in sLOX-1 and rheumatoid factor (RF) were analyzed by multivariate linear regression. RESULTS: Plasma sLOX-1 level was significantly correlated with RF titer and other clinical parameters. The longitudinal analyses showed that changes in sLOX-1 were significantly correlated with changes in RF titers and with those at baseline. Multivariate linear regression analysis revealed that changes in RF and baseline RF were predictive factors for changes in sLOX-1. Conversely, the changes in RF were significantly correlated with the changes in sLOX-1 in all years. A stepwise regression analysis showed that the change in sLOX-1 was a predictive factor for the change in RF. CONCLUSIONS: The change in sLOX-1 has predictive value for assessing the change in RF, indicating the usefulness of sLOX-1 in clinical practice.


Assuntos
Artrite Reumatoide , Fator Reumatoide , Artrite Reumatoide/diagnóstico , Biomarcadores , Ensaio de Imunoadsorção Enzimática , Humanos , Estudos Longitudinais , Receptores Depuradores Classe E
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