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1.
Int J Gynecol Pathol ; 36(1): 90-94, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27362904

RESUMO

Minimal-deviation endometrioid adenocarcinoma (MDEA) of the uterine cervix is a rare tumor that may be confused histologically with a number of benign lesions as well as other types of endocervical neoplasia. The histologic and immunohistochemical features of MDEA have been described in case reports and in small series, but correlation of these findings with ultrastructural examination has not been documented. Herein we report a 51-yr-old patient who underwent hysterectomy for menorrhagia and was found to have a clinically unsuspected, stage IB cervical MDEA. The light microscopic, immunohistochemical, and electron microscopic features of the tumor are described, with the most significant ultrastructural abnormality being the presence of abnormal cilia and ciliogenesis.


Assuntos
Adenocarcinoma/diagnóstico , Carcinoma Endometrioide/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/ultraestrutura , Carcinoma Endometrioide/patologia , Carcinoma Endometrioide/ultraestrutura , Colo do Útero/patologia , Colo do Útero/ultraestrutura , Diagnóstico Diferencial , Feminino , Humanos , Histerectomia , Pessoa de Meia-Idade , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/ultraestrutura
2.
Hum Mol Genet ; 22(19): 3987-97, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23736297

RESUMO

More than 200 mutations in the skeletal muscle α-actin gene (ACTA1) cause either dominant or recessive skeletal muscle disease. Currently, there are no specific therapies. Cardiac α-actin is 99% identical to skeletal muscle α-actin and the predominant actin isoform in fetal muscle. We previously showed cardiac α-actin can substitute for skeletal muscle α-actin, preventing the early postnatal death of Acta1 knock-out mice, which model recessive ACTA1 disease. Dominant ACTA1 disease is caused by the presence of 'poison' mutant actin protein. Experimental and anecdotal evidence nevertheless indicates that the severity of dominant ACTA1 disease is modulated by the relative amount of mutant skeletal muscle α-actin protein present. Thus, we investigated whether transgenic over-expression of cardiac α-actin in postnatal skeletal muscle could ameliorate the phenotype of mouse models of severe dominant ACTA1 disease. In one model, lethality of ACTA1(D286G). Acta1(+/-) mice was reduced from ∼59% before 30 days of age to ∼12%. In the other model, Acta1(H40Y), in which ∼80% of male mice die by 5 months of age, the cardiac α-actin transgene did not significantly improve survival. Hence cardiac α-actin over-expression is likely to be therapeutic for at least some dominant ACTA1 mutations. The reason cardiac α-actin was not effective in the Acta1(H40Y) mice is uncertain. We showed that the Acta1(H40Y) mice had endogenously elevated levels of cardiac α-actin in skeletal muscles, a finding not reported in dominant ACTA1 patients.


Assuntos
Actinas/genética , Actinas/metabolismo , Terapia Genética , Músculo Esquelético/metabolismo , Doenças Musculares/genética , Doenças Musculares/terapia , Miocárdio/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Genes Recessivos , Humanos , Masculino , Camundongos , Camundongos Knockout , Músculo Esquelético/patologia , Doenças Musculares/metabolismo , Doenças Musculares/mortalidade , Mutação , Fenótipo
3.
J Orthop Translat ; 38: 229-240, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36474855

RESUMO

Background: Glucocorticoid (GC) is one of frequently used anti-inflammatory agents, but its administration is unfortunately accompanied with bone loss. Although sporadic studies indicated that osteocytes are subject to a series of pathological changes under GC stress, including overexpression of cathepsin K, the definite role of osteocytes in GC-induced bone loss remains largely unclear. Methods: Gene expression of Ctsk and protein levels of cathepsin K were assessed in MLO-Y4 cell lines exposed to dexamethasone (Dex) of different time (0, 12, 24 hours) and dose (0, 10-8 and 10-6 M) courses by RT-qPCR and western blotting, respectively. Confocal imaging and immunostaining were then performed to evaluate the effects of osteocyte-derived cathepsin K on type I collagen in a primary osteocyte ex vivo culture system. MitoTracker Red was used to stain mitochondria for mitochondria morphology assessment and JC-1 assay was employed to evaluate the mitochondria membrane potential in MLO-Y4 cells following Dex treatment. Activation of PINK1-mediated mitophagy was evaluated by immunostaining of the PINK1 protein and CytoID assay. Mdivi-1 was used to inhibit mitophagy and siRNAs were used for the inhibition of Pink1 and Atg5. Results: GC triggered osteocytes to produce excessive cathepsin K which in turn led to the degradation of type I collagen in the extracellular matrix in a primary osteocyte ex vivo culture system. Meanwhile, GC administration increased mitochondrial fission and membrane depolarization in osteocytes. Further, the activation of PINK1-mediated mitophagy was demonstrated to be responsible for the diminishment of dysfunctional mitochondria in osteocytes. Examination of relationship between mitophagy and cathepsin K production revealed that inhibition of mitophagy via knocking down Pink1 gene abolished the GC-triggered cathepsin K production. Interestingly, GC's activation effect towards cathepsin K via mitophagy was found to be independent on the canonical autophagy as this effect was not impeded when inhibiting the canonical autophagy via Atg5 suppression. Conclusion: GC-induced PINK1-mediated mitophagy substantially modulates the production of cathepsin K in osteocytes, which could be an underlying mechanism by which osteocytes contribute to the extracellular matrix degradation during bone loss. The Translational potential of this article: Findings of the current study indicate a possible role of osteocyte mitophagy in GC-induced bone loss, which provides a potential therapeutic approach to alleviate GC-induced osteoporosis by targeting PINK1-mediated osteocytic mitophagy.

4.
Nat Commun ; 14(1): 906, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810735

RESUMO

Osteoclasts are giant bone-digesting cells that harbor specialized lysosome-related organelles termed secretory lysosomes (SLs). SLs store cathepsin K and serve as a membrane precursor to the ruffled border, the osteoclast's 'resorptive apparatus'. Yet, the molecular composition and spatiotemporal organization of SLs remains incompletely understood. Here, using organelle-resolution proteomics, we identify member a2 of the solute carrier 37 family (Slc37a2) as a SL sugar transporter. We demonstrate in mice that Slc37a2 localizes to the SL limiting membrane and that these organelles adopt a hitherto unnoticed but dynamic tubular network in living osteoclasts that is required for bone digestion. Accordingly, mice lacking Slc37a2 accrue high bone mass owing to uncoupled bone metabolism and disturbances in SL export of monosaccharide sugars, a prerequisite for SL delivery to the bone-lining osteoclast plasma membrane. Thus, Slc37a2 is a physiological component of the osteoclast's unique secretory organelle and a potential therapeutic target for metabolic bone diseases.


Assuntos
Reabsorção Óssea , Osteoclastos , Camundongos , Animais , Osteoclastos/metabolismo , Transporte Biológico , Lisossomos/metabolismo , Osso e Ossos/metabolismo , Membrana Celular/metabolismo , Reabsorção Óssea/metabolismo
5.
Brain ; 134(Pt 4): 1101-15, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21303860

RESUMO

Mutations in the skeletal muscle α-actin gene (ACTA1) cause a range of pathologically defined congenital myopathies. Most patients have dominant mutations and experience severe skeletal muscle weakness, dying within one year of birth. To determine mutant ACTA1 pathobiology, transgenic mice expressing ACTA1(D286G) were created. These Tg(ACTA1)(D286G) mice were less active than wild-type individuals. Their skeletal muscles were significantly weaker by in vitro analyses and showed various pathological lesions reminiscent of human patients, however they had a normal lifespan. Mass spectrometry revealed skeletal muscles from Tg(ACTA1)(D286G) mice contained ∼25% ACTA1(D286G) protein. Tg(ACTA1)(D286G) mice were crossed with hemizygous Acta1(+/-) knock-out mice to generate Tg(ACTA1)(D286G)(+/+).Acta1(+/-) offspring that were homozygous for the transgene and hemizygous for the endogenous skeletal muscle α-actin gene. Akin to most human patients, skeletal muscles from these offspring contained approximately equal proportions of ACTA1(D286G) and wild-type actin. Strikingly, the majority of these mice presented with severe immobility between postnatal Days 8 and 17, requiring euthanasia. Their skeletal muscles contained extensive structural abnormalities as identified in severely affected human patients, including nemaline bodies, actin accumulations and widespread sarcomeric disarray. Therefore we have created valuable mouse models, one of mild dominant ACTA1 disease [Tg(ACTA1)(D286G)], and the other of severe disease, with a dramatically shortened lifespan [Tg(ACTA1)(D286G)(+/+).Acta1(+/-)]. The correlation between mutant ACTA1 protein load and disease severity parallels effects in ACTA1 families and suggests altering this ratio in patient muscle may be a therapy for patients with dominant ACTA1 disease. Furthermore, ringbinden fibres were observed in these mouse models. The presence of such features suggests that perhaps patients with ringbinden of unknown genetic origin should be considered for ACTA1 mutation screening. This is the first experimental, as opposed to observational, evidence that mutant protein load determines the severity of ACTA1 disease.


Assuntos
Actinas/genética , Modelos Animais de Doenças , Músculo Esquelético/metabolismo , Doenças Musculares/genética , Actinas/metabolismo , Animais , Cromatografia Líquida , Genótipo , Força da Mão/fisiologia , Imuno-Histoquímica , Espectrometria de Massas , Camundongos , Camundongos Knockout , Microscopia Eletrônica , Atividade Motora/genética , Contração Muscular/genética , Doenças Musculares/metabolismo , Fenótipo , Teste de Desempenho do Rota-Rod
6.
J Exp Med ; 197(4): 503-13, 2003 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-12591907

RESUMO

The unique tyrosine kinase binding (TKB) domain of Cbl targets phosphorylated tyrosines on activated protein tyrosine kinases (PTKs); this targeting is considered essential for Cbl proteins to negatively regulate PTKs. Here, a loss-of-function mutation (G304E) in the c-Cbl TKB domain, first identified in Caenorhabditis elegans, was introduced into a mouse and its effects in thymocytes and T cells were studied. In marked contrast to the c-Cbl knockout mouse, we found no evidence of enhanced activity of the ZAP-70 PTK in thymocytes from the TKB domain mutant mouse. This finding contradicts the accepted mechanism of c-Cbl-mediated negative regulation, which requires TKB domain targeting of phosphotyrosine 292 in ZAP-70. However, the TKB domain mutant mouse does show aspects of enhanced signaling that parallel those of the c-Cbl knockout mouse, but these involve the constitutive activation of Rac and not enhanced PTK activity. Furthermore, the enhanced signaling in CD4(+)CD8(+) double positive thymocytes appears to be compensated by the selective down-regulation of CD3 on mature thymocytes and peripheral T cells from both strains of mutant c-Cbl mice.


Assuntos
Proteínas de Caenorhabditis elegans , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/fisiologia , Linfócitos T/fisiologia , Ubiquitina-Proteína Ligases , Animais , Antígenos CD/análise , Antígenos de Diferenciação de Linfócitos T/análise , Sítios de Ligação , Complexo CD3/análise , Antígenos CD5/análise , Receptores ErbB/fisiologia , Feminino , Proteínas de Helminto/fisiologia , Lectinas Tipo C , Masculino , Proteínas de Membrana/análise , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Proteínas Proto-Oncogênicas c-cbl , Receptores de Antígenos de Linfócitos T/análise , Timo/enzimologia , Proteína-Tirosina Quinase ZAP-70 , Proteínas rac de Ligação ao GTP/metabolismo , Domínios de Homologia de src
7.
J Autoimmun ; 35(1): 77-85, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20382503

RESUMO

Antibodies reactive with the ovarian glycoprotein zona pellucida (ZP) have been linked with human female infertility. Anti-fertility vaccines that target ZP antigens have been utilized to restrict pest animal populations and their efficacy is associated with ovary-specific antibody induction. However, the necessity for zona pellucida-specific antibody in mediating infertility has not been examined in vivo. A recombinant mouse cytomegalovirus vaccine encoding murine zona pellucida 3 that induces rapid and complete infertility in BALB/c mice has been produced. The onset of infertility is temporally related to the presence of antibody sequestered into ovarian follicles and binding to the ZP of infected mice and the loss of mature follicles. When this vaccine was inoculated into immunoglobulin-deficient BALB/c mice with a null mutation in the immunoglobulin mu chain gene Igh-6, fertility was unaffected. Passive transfer of serum containing ZP3 antibodies also elicited transient infertility. Electron microscopy of ovarian tissue collected from ZP3-immunized immunocompetent mice demonstrated significant focal thinning of the zona pellucida (ZP) with reduced length and concentration of transzonal processes and many oocytes displayed evidence of injury. None of these changes were found in vaccinated immunoglobulin-deficient mice. These data confirm that ZP3-reactive antibody is necessary and sufficient to induce autoimmune-mediated follicular depletion and fertility suppression following the inoculation of this vaccine, and suggest that this is due to impaired zona pellucida formation. These findings have relevance in understanding the etiology of autoimmune ovarian disease in woman where anti-ZP antibodies are likely to have a causal role in infertility.


Assuntos
Imunoglobulinas/farmacologia , Muromegalovirus/genética , Ovário/metabolismo , Receptores de Superfície Celular/metabolismo , Vacinas Anticoncepcionais , Animais , Complexo Antígeno-Anticorpo/imunologia , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Anticoncepção Imunológica , Feminino , Humanos , Imunoglobulinas/genética , Infertilidade Feminina/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Mutantes , Microscopia Eletrônica , Especificidade de Órgãos , Ovário/efeitos dos fármacos , Ovário/imunologia , Ovário/patologia , Receptores de Superfície Celular/imunologia , Vacinas Sintéticas/genética
8.
J Alzheimers Dis ; 69(1): 59-70, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30932886

RESUMO

Bone, the major structural scaffold of the human body, has recently been demonstrated to interact with several other organ systems through the actions of bone-derived cells and bone-derived cell secretory proteins. Interestingly, the brain is one organ that appears to fall into this interconnected network. Furthermore, the fact that osteoporosis and Alzheimer's disease are two common age-related disorders raises the possibility that these two organ systems are interconnected in terms of disease pathogenesis. This review focuses on the latest evidence demonstrating the impact of bone-derived cells and bone-derived proteins on the central nervous system, and on how this may be relevant in the progression of Alzheimer's disease and for the identification of novel therapeutic approaches to treat this neurodegenerative disorder.


Assuntos
Doença de Alzheimer/patologia , Osso e Ossos/patologia , Encéfalo/patologia , Células-Tronco Mesenquimais/patologia , Microglia/patologia , Osso e Ossos/metabolismo , Encéfalo/metabolismo , Progressão da Doença , Humanos , Células-Tronco Mesenquimais/metabolismo , Microglia/metabolismo
9.
Mol Cell Biol ; 25(12): 5253-69, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15923639

RESUMO

Rab3 proteins are a subfamily of GTPases, known to mediate membrane transport in eukaryotic cells and play a role in exocytosis. Our data indicate that Rab3D is the major Rab3 species expressed in osteoclasts. To investigate the role of Rab3D in osteoclast physiology we examined the skeletal architecture of Rab3D-deficient mice and found an osteosclerotic phenotype. Although basal osteoclast number in null animals is normal the total eroded surface is significantly reduced, suggesting that the resorptive defect is due to attenuated osteoclast activity. Consistent with this hypothesis, ultrastructural analysis reveals that Rab3D(-/-) osteoclasts exhibit irregular ruffled borders. Furthermore, while overexpression of wild-type, constitutively active, or prenylation-deficient Rab3D has no significant effects, overexpression of GTP-binding-deficient Rab3D impairs bone resorption in vitro. Finally, subcellular localization studies reveal that, unlike wild-type or constitutively active Rab3D, which associate with a nonendosomal/lysosomal subset of post-trans-Golgi network (TGN) vesicles, inactive Rab3D localizes to the TGN and inhibits biogenesis of Rab3D-bearing vesicles. Collectively, our data suggest that Rab3D modulates a post-TGN trafficking step that is required for osteoclastic bone resorption.


Assuntos
Reabsorção Óssea , Osteoclastos/fisiologia , Vesículas Transportadoras/metabolismo , Proteínas rab3 de Ligação ao GTP/metabolismo , Animais , Transporte Biológico/fisiologia , Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Células Cultivadas , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Microscopia Eletrônica , Organelas/metabolismo , Osteoclastos/citologia , Osteopetrose/metabolismo , Osteopetrose/patologia , Fenótipo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Tíbia/citologia , Tíbia/metabolismo , Tíbia/patologia , Proteínas rab3 de Ligação ao GTP/genética , Rede trans-Golgi/metabolismo
10.
Invest Ophthalmol Vis Sci ; 46(9): 3031-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16123398

RESUMO

PURPOSE: To investigate the correlation between the presence of the inactive cathepsin D (CatD) and retinal changes in mcd2/mcd2 transgenic mice. METHODS: Computational modeling was used to examine whether CatD mutants maintain competitive substrate binding. D407 cells were transfected with pcDNACatDM1 or pcDNACatDM2, containing procathepsin D (pro-CatD) with 6-bp (CatDM1) or 12-bp (CatDM2) deletions, respectively, flanking the pro-CatD cleavage site, and the aspartic protease activity of the transfected cells was measured. Subsequently, transgenic mice (mcd2/mcd2) containing CatDM2 were generated. Relative transgene copy number and transcript levels in the previously produced mcd/mcd (carrying CatDM1) and mcd2/mcd2 mice were measured by quantitative real-time PCR. Western blot analysis and aspartic protease activity were used to characterize the mutated proteins. Retinal changes were described by using color fundus photography and fluorescein angiography, histology, immunohistochemistry, and electron microscopy. RESULTS: Computational modeling of the CatDM1 and CatDM2 structures indicated that the substrate binding site was not altered. There was limited or no aspartic protease activity associated with CatDM1 and CatDM2 proteins, respectively. Mcd2/mcd2 animals contained a higher amount of inactive CatD than mcd/mcd or wild-type mice. Retinal abnormalities in mcd2/mcd2 mice developed at 3 months of age, earlier than in mcd/mcd mice. These changes included hypopigmentation, hyperfluorescence, retinal pigment epithelial (RPE) cell depigmentation or clumping, cell proliferation, and pleomorphism. Proliferating cells were identified as being of RPE origin. CONCLUSIONS: This study demonstrated a correlation between the presence of the inactive CatD in RPE cells and the development of ophthalmoscopic, cellular, and histologic changes in the retina.


Assuntos
Catepsina D/fisiologia , Degeneração Macular/enzimologia , Epitélio Pigmentado Ocular/enzimologia , Animais , Ácido Aspártico Endopeptidases/metabolismo , Western Blotting , Catepsina D/química , Simulação por Computador , Precursores Enzimáticos/fisiologia , Angiofluoresceinografia , Deleção de Genes , Humanos , Imuno-Histoquímica , Degeneração Macular/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Estrutura Molecular , Epitélio Pigmentado Ocular/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
11.
Am J Surg Pathol ; 27(10): 1380-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14508400

RESUMO

We report a case of gangliocytic paraganglioma of bronchus. A 54-year-old woman underwent bronchoscopy following two episodes of right lower lobe pneumonia over the previous 5 months with unresolved chest radiographic changes. A computerized tomographic scan showed a right lower lobe endobronchial lesion, and at bronchoscopy there was a mass partly occluding the lumen of the bronchus. The biopsy and subsequent bronchoscopic resection showed a tumor with morphologic, immunohistochemical, and ultrastructural features of paragangliomatous, gangliocytic, and Schwann cell differentiation consistent with a gangliocytic paraganglioma. The lesion was treated conservatively with bronchoscopic resection and laser therapy. Histopathologic examination of recurrent tumor at 6 months showed features consistent with paraganglioma. Ten months after initial diagnosis, there was no bronchoscopic evidence of residual tumor. The occurrence of gangliocytic paraganglioma in diverse sites gives cause for the reappraisal of the histogenesis of this fascinating lesion. The variable morphology of this lesion may be an expression of the potential for divergent differentiation of a pluripotent stem cell.


Assuntos
Neoplasias Brônquicas/patologia , Neoplasias Brônquicas/ultraestrutura , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/ultraestrutura , Paraganglioma/patologia , Paraganglioma/ultraestrutura , Biópsia , Neoplasias Brônquicas/diagnóstico por imagem , Neoplasias Brônquicas/cirurgia , Broncoscopia/métodos , Feminino , Humanos , Terapia a Laser , Microscopia Eletrônica , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico por imagem , Recidiva Local de Neoplasia/cirurgia , Paraganglioma/diagnóstico por imagem , Paraganglioma/cirurgia , Tomografia Computadorizada por Raios X
12.
J Med Microbiol ; 48(12): 1095-1102, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10591163

RESUMO

The effect of aging on host resistance to systemic candidosis was assessed by monitoring the course of infection in 16-month-old CBA/CaH mice (aged non-immune) and in a comparable group that had been infected with a sublethal dose of Candida albicans at 6 weeks of age (aged immune). Aged non-immune mice showed rapid progression of the disease, with a marked increase in the number of mycelia in the brain and kidney, and early morbidity. Foci of myocardial necrosis were evident, but inflammatory cells were sparse. The histological picture in the aged immune mice was similar to that in the aged non-immune group, although fewer mycelial aggregates were seen. Both groups of aged mice showed a significantly lower fungal burden in the brain on day 1 of infection, but on day 4, colony counts increased significantly in the aged non-immune mice. Comparison of cytokine gene expression in the infected brains showed that the relative amount of interferon-gamma and tumour necrosis factor-alpha cDNA were similar in all three groups. Interleukin-6 was elevated in both infected non-immune and uninfected aged mice. Aged immune mice showed no morbidity after challenge, and both colonisation and tissue damage were reduced in comparison with the aged non-immune animals.


Assuntos
Envelhecimento/imunologia , Candida albicans/imunologia , Candidíase/imunologia , Animais , Encéfalo/imunologia , Encéfalo/microbiologia , Encéfalo/patologia , Candida albicans/isolamento & purificação , Candidíase/microbiologia , Candidíase/patologia , Citocinas/genética , Citocinas/metabolismo , DNA Complementar/genética , Suscetibilidade a Doenças , Feminino , Coração/microbiologia , Rim/microbiologia , Rim/patologia , Camundongos , Camundongos Endogâmicos CBA , Miocardite/patologia , Miocárdio/patologia , Reação em Cadeia da Polimerase
13.
Biomed Mater ; 9(1): 015015, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24457429

RESUMO

Recent experimental studies have shown the suitability of silk fibroin scaffold (SFS) and porcine-derived acellular collagen I/III scaffold (ACS) as onlay graft materials for tympanic membrane perforation repair. The aims of this study were to further characterize and evaluate the in vivo biocompatibility of SFS and ACS compared with commonly used materials such as Gelfoam and paper in a rat model. The scaffolds were implanted in subcutaneous (SC) tissue and middle ear (ME) cavity followed by histological and otoscopic evaluation for up to 26 weeks. Our results revealed that SFS and ACS were well tolerated and compatible in rat SC and ME tissues throughout the study. The tissue response adjacent to the implants evaluated by histology and otoscopy showed SFS and ACS to have a milder tissue response with minimal inflammation compared to that of paper. Gelfoam gave similar results to SFS and ACS after SC implantation, but it was found to be associated with pronounced fibrosis and osteoneogenesis after ME implantation. It is concluded that SFS and ACS both were biocompatible and could serve as potential alternative scaffolds for tissue engineering in the ear.


Assuntos
Materiais Biocompatíveis/química , Colágeno/química , Orelha/patologia , Fibroínas/química , Seda/química , Engenharia Tecidual/métodos , Animais , Bombyx , Fibrose , Géis , Imuno-Histoquímica , Inflamação , Masculino , Osteogênese , Otoscopia , Ratos , Ratos Sprague-Dawley , Suínos , Alicerces Teciduais , Membrana Timpânica/patologia
16.
J Cell Biol ; 185(5): 903-15, 2009 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19468071

RESUMO

Skeletal muscle alpha-actin (ACTA1) is the major actin in postnatal skeletal muscle. Mutations of ACTA1 cause mostly fatal congenital myopathies. Cardiac alpha-actin (ACTC) is the major striated actin in adult heart and fetal skeletal muscle. It is unknown why ACTC and ACTA1 expression switch during development. We investigated whether ACTC can replace ACTA1 in postnatal skeletal muscle. Two ACTC transgenic mouse lines were crossed with Acta1 knockout mice (which all die by 9 d after birth). Offspring resulting from the cross with the high expressing line survive to old age, and their skeletal muscles show no gross pathological features. The mice are not impaired on grip strength, rotarod, or locomotor activity. These findings indicate that ACTC is sufficiently similar to ACTA1 to produce adequate function in postnatal skeletal muscle. This raises the prospect that ACTC reactivation might provide a therapy for ACTA1 diseases. In addition, the mouse model will allow analysis of the precise functional differences between ACTA1 and ACTC.


Assuntos
Actinas/fisiologia , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Actinas/genética , Animais , Perfilação da Expressão Gênica , Coração/embriologia , Camundongos , Camundongos Knockout , Músculo Esquelético/ultraestrutura , Miocárdio/ultraestrutura , Isoformas de Proteínas/fisiologia
18.
J Immunol ; 175(5): 3235-43, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16116214

RESUMO

Cytotoxic lymphocytes express a large family of granule serine proteases, including one member, granzyme (Grz)M, with a unique protease activity, restricted expression, and distinct gene locus. Although a number of Grzs, including GrzM, have been shown to mediate target cell apoptosis in the presence of perforin, the biological activity of Grz has been restricted to control of a number of viral pathogens, including two natural mouse pathogens, ectromelia, and murine CMV (MCMV). In this article, we describe the first reported gene targeting of GrzM in mice. GrzM-deficient mice display normal NK cell/T cell development and homeostasis and intact NK cell-mediated cytotoxicity of tumor targets as measured by membrane damage and DNA fragmentation. GrzM-deficient mice demonstrated increased susceptibility to MCMV infection typified by the presence of more viral inclusions and transiently higher viral burden in the visceral organs of GrzM-deficient mice compared with wild-type (WT) mice. The cytotoxicity of NK cells from MCMV-infected GrzM-deficient mice remained unchanged and, like WT control mice, GrzM-deficient mice eventually effectively cleared MCMV infection from the visceral organs. In contrast, GrzM-deficient mice were as resistant as WT control mice to mouse pox ectromelia infection, as well as challenge with a number of NK cell-sensitive tumors. These data confirm a role for GrzM in the host response to MCMV infection, but suggest that GrzM is not critical for NK cell-mediated cytotoxicity.


Assuntos
Ectromelia Infecciosa/imunologia , Infecções por Herpesviridae/imunologia , Muromegalovirus , Serina Endopeptidases/fisiologia , Animais , Citotoxicidade Imunológica , Granzimas , Infecções por Herpesviridae/patologia , Homeostase , Células Matadoras Naturais/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Muromegalovirus/imunologia , Neoplasias Experimentais/imunologia , Linfócitos T/fisiologia
19.
Med Sci Monit ; 11(2): CR53-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15668631

RESUMO

BACKGROUND: Studies of molecular changes in hair as possible biomarkers for specific cancers revealed an additional molecular change in the diffraction patterns of some persons aged over 75. This change was found to correlate with the presence of Alzheimer's disease (AD). To confirm this correlation and its relation to the presence of a human APP mutation, known to definitely cause AD, hairs were examined from AD patients, pregnant women known to have an increase in plasma beta amyloid and transgenic mice carrying a mutated human APP gene. Patients were clinically examined by an experienced physician who recorded the patient's history and completed physical and neurological examinations. Hair samples were held taut and centred in the beam. The diffraction patterns were collected on Fuji-Bas Imaging plates and analysed using standard programs. MATERIAL/METHODS: A fan-shaped set of spot-like reflections was observed in the equatorial diffraction patterns from the hair of all AD patients and all third trimester pregnant women. Combined fibre diffraction of hair and histopathologic examination of brains from transgenic mice carrying a mutated human APP gene confirmed that these changes are related to the mutated human APP genes and the formation of beta amyloid plaques. RESULTS: Here we show results that fibre diffraction analysis would provide a non-invasive, accurate bio-marker for Alzheimer's disease. Our results are consistent with the hypothesis that this marker is related to the presence of mutated human APP genes and indicate that the structural change precedes the significant development of plaques. CONCLUSIONS: Here we show results that fibre diffraction analysis would provide a non-invasive, accurate bio-marker for Alzheimer's disease. Our results are consistent with the hypothesis that this marker is related to the presence of mutated human APP genes and indicate that the structural change precedes the significant development of plaques.


Assuntos
Doença de Alzheimer/diagnóstico , Modelos Animais de Doenças , Cabelo/metabolismo , Cabelo/patologia , Programas de Rastreamento/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Animais , Biomarcadores/análise , Encéfalo/metabolismo , Encéfalo/patologia , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Gravidez , Síncrotrons
20.
Microbiology (Reading) ; 145 ( Pt 7): 1631-1640, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10439402

RESUMO

The role of T lymphocytes in host responses to sublethal systemic infection with Candida albicans was evaluated by mAb depletion of CD4+ and CD8+ cells from BALB/c and CBA/CaH mice, which develop mild and severe tissue damage, respectively. Depletion of CD4+ lymphocytes from BALB/c mice markedly increased tissue damage, but did not alter the course of infection. In CBA/CaH mice, depletion of CD4+ cells abrogated tissue destruction in both brain and kidney at day 4 after infection, and significantly decreased fungal colonization in the brain. However, the severity of tissue lesions increased relative to controls from day 8 onwards. A small increase in tissue damage was evident in both mouse strains after depletion of CD8+ cells. There were no major differences between days 4 and 8 after infection in cDNA cytokine profiles of CD4+ lymphocytes from either BALB/c or CBA/CaH mice. After passive transfer into infected syngeneic recipients, spleen cells from infected CBA/CaH mice markedly increased tissue damage when compared to controls, and also caused a significant increase in fungal colonization in the brain. A similar transfer in BALB/c mice increased the number of inflammatory cells in and around the lesions, but had no effect on the fungal burden in brain and kidney. The data demonstrate that both CD4+ and CD8+ lymphocytes contribute to the reduction of tissue damage after systemic infection with C. albicans, and that the development and expression of CD4+ lymphocyte effector function is influenced by the genetic background of the mouse.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Candida albicans/imunologia , Candidíase/imunologia , Transferência Adotiva , Animais , Encéfalo/microbiologia , Encéfalo/patologia , Candidíase/microbiologia , Candidíase/patologia , Citocinas/biossíntese , Citocinas/genética , Feminino , Rim/microbiologia , Rim/patologia , Depleção Linfocítica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos CBA , Especificidade da Espécie , Baço/citologia , Baço/imunologia
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