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1.
Appl Opt ; 63(8): 1971-1981, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568637

RESUMO

The extraction of phase information is crucial in moiré tomography for achieving accurate results. In this paper, a method for extracting phase information of moiré fringes based on the Morlet continuous wavelet transform is introduced. A detailed exposition of the theoretical deduction and algorithmic procedure of this method is provided. And then, to validate the feasibility and applicability of this approach, four flow fields are conducted as test objects for experiments. Based on that, the phase results provided by the Morlet continuous wavelet transform are compared with those obtained by the reported techniques such as Fourier transform and Gabor wavelet transform. It is evident that Morlet continuous wavelet transform demonstrates superior accuracy and smoothness, which proves the reliability of this method. In summary, the method presented in this study probably offers an effective method with broad applications.

2.
Mol Biol Rep ; 50(10): 8385-8395, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37615925

RESUMO

BACKGROUND: Fanconi anemia (FA) is a devastating hereditary disorder for which we desperately need a novel therapeutic strategy. It is caused by mutations in one of at least 22 genes in the FA pathway and is characterized by developmental abnormalities, bone marrow failure, and cancer predisposition. The FA pathway is required for the efficient repair of damaged DNA, including interstrand cross-links (ICL). Recent studies indicate formaldehyde as an ultimate endogenous cause of DNA damage in FA pathophysiology. Formaldehyde can form DNA adducts as well as ICLs by inducing covalent linkages between opposite strands of double-stranded DNA. METHODS AND RESULTS: In this study, we generated a disease model of FA in zebrafish by disrupting the ube2t or fancd2 gene, which resulted in a striking phenotype of female-to-male sex reversal. Since formaldehyde is detoxified from the body by alcohol dehydrogenase 5 (ADH5), we generated fancd2-/-/adh5-/- zebrafish. We observed a body size reduction and a lower number of mature spermatozoa than wild-type or single knockout zebrafish. To evaluate if increased activity in ADH5 can affect the FA phenotype, we overexpressed human ADH5 in fancd2-/- zebrafish. The progress of spermatogenesis seemed to be partially recovered due to ADH5 overexpression. CONCLUSIONS: Our results suggest potential utility of an ADH5 enzyme activator as a therapeutic measure for the clearance of formaldehyde and treatment of FA.


Assuntos
Anemia de Fanconi , Peixe-Zebra , Animais , Masculino , Humanos , Feminino , Peixe-Zebra/genética , Anemia de Fanconi/genética , Dano ao DNA , Reparo do DNA , Fenótipo , Formaldeído
3.
Int J Ophthalmol ; 14(3): 341-348, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33747807

RESUMO

AIM: To study the effect of zymosan, a ligand found on the surface of fungi, on gap junctional intercellular communication (GJIC) in cultured human corneal fibroblasts (HCFs). METHODS: Zymosan was added to the medium of cultured HCFs with or without the administration of mitogen-activated protein kinase (MAPK) inhibitors or the inhibitor kappa B kinase 2 (IKK2) inhibitor IV. The protein and mRNA levels of connexin 43 (Cx43) in HCFs were measured by Western blot, immunofluorescence, and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analyses. The GJIC activity was tested using a dye-coupling assay. RESULTS: The reduction of Cx43 protein and mRNA levels as well as a significant decrease in GJIC activity were observed in cultured HCFs when zymosan was added into the culture medium. Compared with controls (no zymosan), the protein level of Cx43 was reduced by 45% and 54% in the presence of zymosan at 200 and 600 µg/mL, respectively (P<0.05); and it was reduced by 45%, 48%, and 75% in the presence of zymosan (600 µg/mL) for 24, 36, and 48h, respectively (P<0.05). The mRNA expression of Cx43 was reduced by 98% in the presence of zymosan (P<0.05). The effects of zymosan on Cx43 expression and GJIC activity were attenuated by the administration of PD98059 [an extracellular signal-regulated kinase (ERK) signaling inhibitor] (P<0.05), c-Jun NH2-terminal kinase (JNK) inhibitor II (P<0.05), and IKK2 inhibitor IV (P<0.05). CONCLUSION: Zymosan inhibits the activity of GJIC in cultured HCFs. This effect is likely regulated via the nuclear factor-κB (NF-κB), MAPK/ERK, and JNK signaling pathways. The inhibitory effects of zymosan on Cx43 expression and GJIC activity in HCFs may induce damage of corneal stroma during corneal fungal infection.

4.
Curr Eye Res ; 45(9): 1043-1050, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32078434

RESUMO

PURPOSE/AIM: Corneal stromal fibroblasts are connected to each other via gap junctions, which contribute to maintenance of corneal homeostasis. Viral infection of the corneal stroma can result in inflammation and scarring. The effects of polyinosinic-polycytidylic acid [poly(I:C)], an analog of viral double-stranded RNA, on gap junctional intercellular communication (GJIC) in cultured human corneal fibroblasts (HCFs) were examined. MATERIALS AND METHODS: Cultured HCFs were exposed to poly(I:C) in the absence or presence of inhibitors of mitogen-activated protein kinase (MAPK) signaling or the antioxidant N-acetyl-L-cysteine (NAC). Expression of the gap junction protein connexin 43 (Cx43) was examined by immunoblot and immunofluorescence analyses. The level of Cx43 mRNA or microRNA-21 or -130a was determined by quantitative reverse transcription-polymerase chain reaction analysis. GJIC was measured with a dye coupling assay. The amount of malondialdehyde and the activity of superoxide dismutase (SOD) were measured with assay kits. RESULTS: Exposure of HCFs to poly(I:C) resulted in down-regulation of Cx43 expression and GJIC activity as well as in up-regulation of microRNA-21 expression. Poly(I:C) increased the amount of malondialdehyde and reduced the activity of SOD in the cells, and these effects were prevented by NAC. The inhibitory effects of poly(I:C) on both Cx43 expression and GJIC activity were attenuated by NAC and by c-Jun NH2-terminal kinase (JNK) inhibitor II. CONCLUSIONS: Poly(I:C) inhibited Cx43 expression and GJIC in cultured HCFs, possibly as a result of the associated up-regulation of microRNA-21. Poly(I:C) also increased oxidative stress in these cells, and such stress together with signaling by the MAPK JNK was implicated in the effects of poly(I:C) on Cx43 expression and GJIC activity. Down-regulation of GJIC activity among corneal fibroblasts by double-stranded RNA may thus contribute to the disruption of stromal homeostasis during viral infection of the cornea.


Assuntos
Antivirais/farmacologia , Comunicação Celular/efeitos dos fármacos , Conexina 43/metabolismo , Ceratócitos da Córnea/efeitos dos fármacos , Junções Comunicantes/efeitos dos fármacos , Poli I-C/farmacologia , Acetilcisteína/farmacologia , Células Cultivadas , Conexina 43/genética , Ceratócitos da Córnea/metabolismo , Regulação para Baixo , Imunofluorescência , Humanos , Immunoblotting , Malondialdeído/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Reação em Cadeia da Polimerase em Tempo Real , Superóxido Dismutase/metabolismo
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