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The impact of oral administration of mechanically fibrillated cellulose nanofibers (fib-CNF), a commonly used nanofiber, on toxicity and health remains unclear, despite reports of the safety and beneficial effects of chitin-based nanofibers. Thus, evaluating the oral toxicity of fib-CNF in accordance with OECD Test Guideline 407 (TG407) is essential. This study aimed to assess the safety of orally administered fib-CNF through an acute toxicity study in rats, following the OECD TG407 guidelines for 4 weeks. CNF "BiNFi-s" FMa-10005, derived from mechanically fibrillated pulp cellulose, was administered via gavage to male and female Crl:CD(SD) rats at doses of 50, 150, 500, and 1000 mg/kg/day for 28 days, with a control group receiving water for injection. The study evaluated the toxic effects of repeated administration, and the rats were monitored for an additional 14 days post-administration to assess recovery from any toxic effects. The results showed no mortality in either sex during the administration period, and no toxicological effects related to the test substance were observed in various assessments, including general condition and behavioral function observations, urinalysis, hematological examination, blood biochemical examination, necropsy findings, organ weights, and histopathological examination. Notably, only female rats treated with 1000 mg/kg/day of CNF exhibited a consistent reduction in body weight during the 14-day recovery period after the end of treatment. They also showed a slight decrease in pituitary and liver weights. However, hematological and blood biochemical tests did not reveal significant differences, suggesting a potential weight-suppressive effect of CNF ingestion.
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INTRODUCTION: The extent of surgical resection for tongue tumors is determined by tumor size, potentially affecting oral function and quality of life (QoL). However, the relationship between oral dysfunction and QoL decline due to glossectomy extent remains unexplored. Therefore, these correlations and their predictive value for postoperative QoL decline were elucidated. METHODS: Patients treated for tongue cancer at our hospital between 2018 and 2022 were categorized by partial, hemi, or subtotal/total glossectomy. Assessments included swallowing function (RSST), articulation (Oral Diadochokinesis (ODK)), mastication, tongue pressure, and oral moisture. QoL was measured using the Oral Health Impact Profile-14 (OHIP-14). Differences within parameters were assessed using Kruskal-Wallis tests, and between-group comparisons via Mann-Whitney U tests. Spearman's correlation analysis examined parameter relationship. RESULTS: 35 patients were evaluated. Significant differences were found in ODK [ta] (p = 0.015), [ka] (p = 0.0006), tongue pressure (p = 0.0001), moisture levels (p = 0.031), OHIP-14 domains: physical disability (p = 0.014) and social disability (p = 0.046). ODK [ta] (PG: 5.95, HG: 5.38, TG: 4.03 times), [ka] (PG: 5.56, HG: 4.78, TG: 3.23 times), and tongue pressure (PG: 32.9, HG: 21.2, TG: 10.3 mmHg) decreased with glossectomy extent, while physical (PG: 0.27, HG: 2.38, TG: 2.00) and social disability (PG: 0.18, HG: 0.94, TG: 1.43) worsened. A significant negative correlation was observed between tongue pressure and social disability (p = 0.013, r = -0.36). CONCLUSION: Expanding resection significantly impacted postoperative oral function and QoL. Tongue pressure assessment may predict long-term social disability in patient QoL.
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Mechanically fibrillated cellulose nanofibers, known as fib-CNF (fiber length: 500 nm; diameter: 45 nm), are used in composites and as a natural thickener in foods. To evaluate their safety, we conducted a 28-day study in mice with inhalation exposure at 0.2 mg/body and oral administration of 400 mg/kg/day. Inhalation exposure to fib-CNF caused transient weight loss, changes in blood cell counts, and increased lung weights. These changes were attributed to adaptive responses. The oral administration of fib-CNF for 28 days resulted in no apparent toxic effects except for a slight decrease in platelet counts. The fib-CNF administration using the protocols studied appears to be safe in mice.
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OBJECTIVE: Flap complications continue to be a challenge in microsurgical reconstruction for older adults. We aimed to evaluate the impact of age on surgical outcomes after microvascular reconstruction. STUDY DESIGN: We retrospectively investigated 103 patients with oral squamous cell carcinoma who had undergone microvascular reconstruction surgery to compare microsurgical reconstruction, common postoperative complications, and flap success rates in geriatric (>75 years) and non-geriatric (<75 years) patients. We also evaluated differences based on the American Society of Anesthesiologists Physical Status score. RESULTS: We found no significant differences between the geriatric and non-geriatric groups in peri-operative, postoperative, or general complications. Conversely, we found that delirium and aspiration pneumonia were significantly more likely to occur in geriatric patients and that multiple medical complications were significantly more likely to occur in geriatric patients with a high American Society of Anesthesiologists score. CONCLUSION: Microvascular reconstruction can be performed effectively and without excessive complications in geriatric patients, and age should not be considered a contraindication for this procedure. Comorbidities play a stronger role in the prediction of adverse events.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Procedimentos de Cirurgia Plástica , Humanos , Idoso , Neoplasias Bucais/cirurgia , Carcinoma de Células Escamosas/cirurgia , Estudos Retrospectivos , Complicações Pós-Operatórias/epidemiologia , Neoplasias de Cabeça e Pescoço/complicações , Resultado do TratamentoRESUMO
Strain energy density functions are used in CAE analysis of hyperelastic materials such as rubber and elastomers. This function can originally be obtained only by experiments using biaxial deformation, but the difficulty of such experiments has made it almost impossible to put the function to practical use. Furthermore, it has been unclear how to introduce the strain energy density function necessary for CAE analysis from the results of biaxial deformation experiments on rubber. In this study, parameters of the Ogden and Mooney-Rivlin approximations of the strain energy density function were derived from the results of biaxial deformation experiments on silicone rubber, and their validity was verified. These results showed that it is best to determine the coefficients of the approximate equations for the strain energy density function after 10 cycles of repeated elongation of rubber in an equal biaxial deformation state, followed by equal biaxial elongation, uniaxial constrained biaxial elongation, and uniaxial elongation to obtain these three stress-strain curves.
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BACKGROUND: High-Mobility Group Box 1 (HMGB1) and HMGB2 are chromatin-associated proteins that belong to the HMG protein family, and are involved in the regulation of DNA transcription during cell differentiation, proliferation and regeneration in various tissues. However, the role of HMGB2 in ovarian folliculogenesis is largely unknown. METHODS: We investigated the functional role of HMGB1 and HMGB2 in ovarian folliculogenesis and fertilization using C57BL/6 wild type (WT) and HMGB2-knockout (KO) mice. Ovarian tissues were obtained from WT and HMGB2-KO mice at postnatal days 0, 3, 7, and 2, 6 months of age, then performed immunohistochemistry, qPCR and Western blotting analyses. Oocyte fertilization capability was examined by natural breeding and in vitro fertilization experiments. RESULTS: In HMGB2-KO mice, ovary weight was decreased due to reduced numbers of oocytes and follicles. Natural breeding and in vitro fertilization results indicated that HMGB2-KO mice are subfertile, but not sterile. Immunohistochemistry showed that oocytes expressed HMGB2, but not HMGB1, in neonatal and adult WT ovaries. Interestingly, in HMGB2-KO ovaries, a compensatory increase in HMGB1 was found in oocyte nuclei of neonatal and 2-month-old mice; however, this was lost at 6 months of age. CONCLUSIONS: The depletion of HMGB2 led to alterations in ovarian morphology and function, suggesting that HMGB2 plays an essential role in ovarian development, folliculogenesis and fertilization.
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Proteína HMGB2 , Ovário , Feminino , Animais , Camundongos , Ovário/metabolismo , Proteína HMGB2/genética , Proteína HMGB2/metabolismo , Camundongos Endogâmicos C57BL , Oócitos/metabolismo , Fatores de Transcrição/metabolismo , FertilidadeRESUMO
Although Mohs paste can control bleeding, exudates, and odors from tumors, there have been no reports of the combination of Mohs paste with other treatments, such as chemotherapy, in oral cancer. Here, we report the combination of Mohs paste and chemotherapy for a case of metastatic oral cancer to the precordium skin and bilateral axillary lymph nodes. The tumors almost completely disappeared after the treatment. Combination therapy of Mohs paste and chemotherapy appears to have a better antitumor effect than Mohs paste alone.
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Neoplasias Bucais , Pele , Terapia Combinada , Hemorragia/etiologia , Humanos , Linfonodos , Neoplasias Bucais/complicações , Neoplasias Bucais/tratamento farmacológicoRESUMO
Hepatocyte growth factor (HGF) activator inhibitor type-1 (HAI-1), encoded by the SPINT1 gene, is a transmembrane protease inhibitor that regulates membrane-anchored serine proteases, particularly matriptase. Here, we explored the role of HAI-1 in tongue squamous cell carcinoma (TSCC) cells. An immunohistochemical study of HAI-1 in surgically resected TSCC revealed the cell surface immunoreactivity of HAI-1 in the main portion of the tumor. The immunoreactivity decreased in the infiltrative front, and this decrease correlated with enhanced lymphatic invasion as judged by podoplanin immunostaining. In vitro homozygous deletion of SPINT1 (HAI-1KO) in TSCC cell lines (HSC3 and SAS) suppressed the cell growth rate but significantly enhanced invasion in vitro. The loss of HAI-1 resulted in enhanced pericellular activities of proteases, such as matriptase and urokinase-type plasminogen activator, which induced activation of HGF/MET signaling in the co-culture with pro-HGF-expressing fibroblasts and plasminogen-dependent plasmin generation, respectively. The enhanced plasminogen-dependent plasmin generation was abrogated partly by matriptase silencing. Culture supernatants of HAI-1KO cells had enhanced potency for converting the proform of vascular endothelial growth factor-C (VEGF-C), a lymphangiogenesis factor, into the mature form in a plasminogen-dependent manner. Furthermore, HGF significantly stimulated VEGF-C expression in TSCC cells. Orthotopic xenotransplantation into nude mouse tongue revealed enhanced lymphatic invasion of HAI-1KO TSCC cells compared to control cells. Our results suggest that HAI-1 insufficiency leads to dysregulated pericellular protease activity, which eventually orchestrates robust activation of protease-dependent growth factors, such as HGF and VEGF-C, in a tumor microenvironment to contribute to TSCC progression.
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Carcinoma de Células Escamosas , Proteínas Secretadas Inibidoras de Proteinases , Neoplasias da Língua , Animais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Fibrinolisina/genética , Homozigoto , Humanos , Camundongos , Plasminogênio/genética , Proteínas Secretadas Inibidoras de Proteinases/genética , Proteínas Secretadas Inibidoras de Proteinases/metabolismo , Deleção de Sequência , Serina Endopeptidases , Neoplasias da Língua/genética , Neoplasias da Língua/patologia , Microambiente Tumoral , Fator C de Crescimento do Endotélio Vascular/genéticaRESUMO
High-mobility group box 2 (HMGB2) is a chromatin-associated protein that is an important regulator of gene transcription, recombination, and repair processes. The functional importance of HMGB2 has been reported in various organs, including the testis, heart, and cartilage. However, its role in the ovary is largely unknown. In this study, ovary tissues from wild-type (WT) and HMGB2-knock-out (KO) mice were examined by histopathological staining and immunohistochemistry. The ovary size and weight were significantly lower in HMGB2-KO mice than in age-matched WT littermates. Histopathological analysis revealed ovarian atrophy and progressive fibrosis in 10-month-old HMGB2-KO mouse ovaries. Compared to age-matched WT mice, the numbers of oocytes and developing follicles were significantly decreased at 2 months of age and were completely depleted at 10 months of age in HMGB2-KO mice. Immunohistochemistry revealed the expression of HMGB2 in the granulosa cells of developing follicles, oocytes, some corpora lutea, and stromal cells. Importantly, HMGB2-positive cells were co-localized with estrogen receptor beta (ERß), but not ERα. Estrogen response element-binding activity was demonstrated by southwestern histochemistry, and it was decreased in HMGB2-KO mouse ovaries. Cell proliferation activity was also decreased in HMGB2-KO mouse ovaries in parallel with the decreased folliculogenesis. These results indicated that the depletion of HMGB2 induced ovarian atrophy that was characterized by a decreased ovarian size and weight, progressive fibrosis, as well as decreased oocytes and folliculogenesis. In conclusion, we demonstrated the crucial role of HMGB2 in mouse ovarian folliculogenesis through ERß expression.
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Receptor beta de Estrogênio , Proteína HMGB2 , Animais , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/análise , Receptor beta de Estrogênio/genética , Receptor beta de Estrogênio/metabolismo , Feminino , Células da Granulosa , Proteína HMGB2/análise , Proteína HMGB2/genética , Proteína HMGB2/metabolismo , Camundongos , Camundongos Knockout , Ovário/metabolismoRESUMO
MEL1 (MDS1/EVI1-like gene 1/PRDM16), a zinc finger protein, is located near the chromosomal breakpoint at 1p36 in human acute myeloid leukemia (AML) cells with the t (1; 3) (p36; q21) translocation. Mel1/Prdm16 is not only a causative gene of leukemia, but also has multiple regulatory functions, such as the regulation of fat metabolism. To investigate the function of Mel1/Prdm16, we generated Mel1/Prdm16-deficient mice, but homozygous deficiency (Mel1/Prdm16-/-) was embryonic lethal at E 11.5. Heterozygous mice showed abnormal cartilage and bone formation in the postnatal skull and long bones, suggesting that Mel1/Prdm16 expression plays an important role in bone development. In osteoblast and chondrocyte cell lines, Mel1/Prdm16 promotes the differentiation of chondrocytes and regulates the differentiation of osteoblasts. Transient repression of the master regulator Runx2 is required for chondrocyte differentiation at an early stage of differentiation. However, in Mel1/Prdm16-suppressed ATDC5 cells, the initial suppression of Runx2 was lacking and its expression was upregulated at the beginning of differentiation, suggesting that chondrogenic differentiation is suppressed in Mel1/Prdm16+/- mesenchymal progenitor cells because Runx2 expression is upregulated during the early stage of differentiation. Thus, the Mel1/Prdm16 gene may be involved in the early repression of Runx2 expression during osteochondral differentiation and promote chondrogenic differentiation.
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Osso e Ossos/anatomia & histologia , Osso e Ossos/citologia , Diferenciação Celular , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/metabolismo , Animais , Sequência de Bases , Proteína Morfogenética Óssea 2/metabolismo , Cartilagem/patologia , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Proteínas de Ligação a DNA/deficiência , Proteínas de Homeodomínio/metabolismo , Camundongos , Camundongos Knockout , Modelos Biológicos , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese , Transdução de Sinais , Fatores de Transcrição/deficiênciaRESUMO
To reduce skin irritation and allergic symptoms caused by long-term mask use, we produced a mask with a filter effect by laminating nanofibers on habutae silk fabric, a specialty of Japan's Fukui Prefecture, using the electrospinning method. We investigated the filter characteristics of silk fabrics with different weave structures (habutae, flat crepe, and twill). We found that woven fabrics alone could not sufficiently block particles finer than 1 µm, even when the fabric layers were overlapped. Therefore, we had a nanofiber filter layer fabricated on the surface of habutae fabric by the electrospinning method at a weight of 1 g/m2. The nanofibers removed more than 94% of 0.3 µm-particles, which are similar to the size of virus particles. However, the nanofiber layer was so dense that it caused an increase in pressure drop, so we made the nanofiber layer thinner and fabricated the filter on the surface of the habutae fabric at 0.5 g/m2. A three-dimensional mask consisting of two woven fabrics, one with a nanofiber layer on the inside and the other with a normal woven fabric without a nanofiber layer on the outside, was fabricated and tested on 95 subjects. The subjects reported that the nanofiber habutae masks were more comfortable than nonwoven masks. Moreover, the silk woven masks did not cause allergic symptoms such as skin irritation.
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Although large exons cannot be readily recognized by the spliceosome, many are evolutionarily conserved and constitutively spliced for inclusion in the processed transcript. Furthermore, whether large exons may be enriched in a certain subset of proteins, or mediate specific functions, has remained unclear. Here, we identify a set of nearly 3,000 SRSF3-dependent large constitutive exons (S3-LCEs) in human and mouse cells. These exons are enriched for cytidine-rich sequence motifs, which bind and recruit the splicing factors hnRNP K and SRSF3. We find that hnRNP K suppresses S3-LCE splicing, an effect that is mitigated by SRSF3 to thus achieve constitutive splicing of S3-LCEs. S3-LCEs are enriched in genes for components of transcription machineries, including mediator and BAF complexes, and frequently contain intrinsically disordered regions (IDRs). In a subset of analyzed S3-LCE-containing transcription factors, SRSF3 depletion leads to deletion of the IDRs due to S3-LCE exon skipping, thereby disrupting phase-separated assemblies of these factors. Cytidine enrichment in large exons introduces proline/serine codon bias in intrinsically disordered regions and appears to have been evolutionarily acquired in vertebrates. We propose that layered splicing regulation by hnRNP K and SRSF3 ensures proper phase-separation of these S3-LCE-containing transcription factors in vertebrates.
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Éxons , Fatores de Processamento de Serina-Arginina/genética , Fatores de Transcrição/genética , Vertebrados/genética , Animais , Linhagem Celular , Citidina/genética , Evolução Molecular , Ribonucleoproteínas Nucleares Heterogêneas Grupo K/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo K/metabolismo , Humanos , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Camundongos , Poliadenilação , Splicing de RNA , Proteínas de Ligação a RNA/genética , Fatores de Processamento de Serina-Arginina/metabolismo , Fatores de Transcrição/metabolismoRESUMO
Commingled yarns consisting of thermoplastic nylon fibers and carbon fibers can be used to produce superior carbon fiber reinforced thermoplastics (CFRTP) by applying fiber spreading technology after commingling. In this study, we examined whether spread commingled carbon fiber/nylon fiber yarns could reduce the impregnation distance, as there are few reports on this. From this study, the following are revealed. The impregnation speed of the nylon resin on the carbon fiber was very fast, less than 1 min. As the molding time increased, the tensile strength and tensile fracture strain slightly decreased, and the nylon resin deteriorated. The effects of molding time on flexural strength, flexural modulus, and flexural fracture strain were negligible. From the cross-sectional observation conducted to confirm the impregnation state of the matrix resin, no voids were observed in the molded products, regardless of molding time or molding pressure, indicating that resin impregnation into the carbon fiber bundle of the spread commingled yarn fabric was completed at a molding pressure of 5 MPa and a molding time of 5 min.
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Prostasin is a glycosylphosphatidylinositol-anchored serine protease widely expressed in epithelial cells, with crucial epidermal barrier functions. Evidence has suggested prostasin may have served as a tumor suppressor in various cancers, but its role in oral squamous cell carcinoma (OSCC) remains unclear. Thus, herein, we conducted an immunohistochemical prostasin study in 119 resected OSCC cases. Prostasin expression was decreased in 63% (75/119) of cases. OSCC with decreased prostasin immunoreactivity (low prostasin cases) tended to show a higher histological grade (p = 0.0088) and a more infiltrative cancer cell morphology (p = 0.0024). We then explored the role of prostasin in the OSCC cell lines: SAS and HSC-4. SAS did not express detectable prostasin levels, whereas HSC-4 expressed low but distinct levels. Prostasin overexpression suppressed the proliferation and migration of both OSCC lines in vitro. Conversely, prostasin silencing significantly enhanced growth rates of HSC-4. Finally, we analyzed the impact of prostasin expression on the prognosis of patients with OSCC; decreased expression tended to correlate with shorter overall survival (p = 0.0291) after resection. This trend was supported by our analyses using a public database (Kaplan-Meier plotter) of head and neck squamous cell carcinomas. In conclusion, we showed decreased prostasin expression was associated with aggressive features and a poorer prognosis of OSCC.
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Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Expressão Gênica/genética , Genes Supressores de Tumor , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Prognóstico , Serina Endopeptidases/fisiologiaRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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The integrin αE known as CD103 binds integrin ß7 to form the complete heterodimeric integrin molecule αEß7. CD103 is mainly expressed by lymphocytes within epithelial tissues of intestine, lung, and skin as well as subsets of mucosal and dermal conventional dendritic cells (cDCs). CD103 has been originally implicated in the attachment of lymphocytes to epithelium in the gut and skin through the interaction with E-cadherin expressed on intestinal epithelial cells, keratinocytes, and Langerhans cells (LCs). However, an impact of CD103 on the cutaneous immune responses and the development of inflammatory skin diseases remains elusive. Here, we report that CD103 regulates the development of psoriasiform dermatitis through the control of the function of cDCs. Deficiency in CD103 exacerbates psoriasiform dermatitis, accompanied by excessive epidermal hyperplasia and infiltration of inflammatory leukocytes. Furthermore, deficiency in CD103 not only accelerates the production of proinflammatory cytokines in psoriatic lesions but also promotes the generation of lymphocytes producing interleukin (IL)-17 in the skin-draining peripheral lymph nodes (PLNs). Under the deficiency in CD103, cDCs localized in PLNs enhance cytokine production following activation. Thus, our findings reveal a pivotal role for CD103 in the control of the function of cDCs to regulate cutaneous inflammation in psoriasiform dermatitis.
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Antígenos CD/metabolismo , Dermatite/metabolismo , Cadeias alfa de Integrinas/metabolismo , Psoríase/metabolismo , Animais , Antígenos CD/genética , Autoimunidade/genética , Autoimunidade/fisiologia , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Dermatite/genética , Feminino , Citometria de Fluxo , Imuno-Histoquímica , Cadeias alfa de Integrinas/genética , Queratinócitos/metabolismo , Células de Langerhans/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Psoríase/genética , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
C-type lectin receptors (CLRs), pattern recognition receptors (PRRs) with a characteristic carbohydrate recognition domain (CRD) in the extracellular portion, mediate crucial cellular functions upon recognition of glycosylated pathogens and self-glycoproteins. CLEC4A is the only classical CLR that possesses an intracellular immunoreceptor tyrosine-based inhibitory motif (ITIM), which possibly transduces negative signals. However, how CLEC4A exerts cellular inhibition remains unclear. Here, we report that the self-interaction of CLEC4A through the CRD is required for the ITIM-mediated suppressive function in conventional dendritic cells (cDCs). Human type 2 cDCs (cDC2) and monocytes display a higher expression of CLEC4A than cDC1 and plasmacytoid DCs (pDCs) as well as B cells. The extracellular portion of CLEC4A specifically binds to a murine cDC cell line expressing CLEC4A, while its extracellular portion lacking the N-glycosylation site or the EPS motif within the CRD reduces their association. Furthermore, the deletion of the EPS motif within the CRD or ITIM in CLEC4A almost completely impairs its suppressive effect on the activation of the murine cDC cell line, whereas the absence of the N-glycosylation site within the CRD exhibits partial inhibition on their activation. On the other hand, antagonistic monoclonal antibody (mAb) to CLEC4A, which inhibits the self-interaction of CLEC4A and its downstream signaling in murine transfectants, enhances the activation of monocytes and monocyte-derived immature DCs upon stimulation with a Toll-like receptor (TLR) ligand. Thus, our findings suggest a pivotal role of the CRD in self-interaction of CLEC4A to elicit the ITIM-mediated inhibitory signal for the control of the function of cDCs.
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Carboidratos/imunologia , Lectinas Tipo C/imunologia , Glicoproteínas de Membrana/imunologia , Receptores Imunológicos/imunologia , Animais , Células Dendríticas/imunologia , Humanos , Motivo de Ativação do Imunorreceptor Baseado em Tirosina/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Reconhecimento de Padrão/imunologiaRESUMO
AIM: Synthetic vascular grafts are widely used in surgical revascularization, mainly for medium- to large-sized vessels. However, synthetic grafts smaller than 6 mm in diameter are associated with a high incidence of thrombosis. In this study, we evaluated silk fibroin, a major protein of silk, with high biocompatibility and biodegradability, as a useful material for extremely-small-diameter vascular grafts. METHODS: A small-sized (0.9 mm inner diameter) graft was braided from a silk fibroin thread. The right carotid arteries of 8- to 14-week-old male C57BL/6 mice were cut at the midpoint, and fibroin grafts (5- to 7-mm in length) were transplanted using a cuff technique with polyimide cuffs. The grafts were harvested at different time points and analyzed histologically. RESULTS: CD31ï¼ endothelial cells had already started to proliferate at 2 weeks after implantation. At 4 weeks, neointima had formed with α-smooth muscle actin+ cells, and the luminal surface was covered with CD31ï¼endothelial cells. Mac3ï¼ macrophages were accumulated in the grafts. Graft patency was confirmed at up to 6 months after implantation. CONCLUSION: This mouse model of arterial graft implantation enables us to analyze the remodeling process and biocompatibility of extremely-small-diameter vascular grafts. Biodegradable silk fibroin might be applicable for further researches using genetically modified mice.
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Implantes Absorvíveis , Materiais Biocompatíveis/química , Prótese Vascular , Fibroínas/química , Animais , Implante de Prótese Vascular , Proliferação de Células , Células Endoteliais/citologia , Masculino , Camundongos Endogâmicos C57BL , Grau de Desobstrução VascularRESUMO
In multinodular lesions or tumors with mixed benign and malignant components, malignant elements may be undetectable using fine-needle aspiration biopsy/cytology in preoperative pathological diagnosis of some cases, because of sampling error.