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1.
Cell Mol Gastroenterol Hepatol ; 17(6): 965-981, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38342302

RESUMO

BACKGROUND & AIMS: Hepatic ischemia-reperfusion injury (HIRI) often occurs in liver surgery, such as partial hepatectomy and liver transplantation, in which myeloid macrophage-mediated inflammation plays a critical role. Cell division cycle 42 (Cdc42) regulates cell migration, cytoskeleton rearrangement, and cell polarity. In this study, we explore the role of myeloid Cdc42 in HIRI. METHODS: Mouse HIRI models were established with 1-hour ischemia followed by 12-hour reperfusion in myeloid Cdc42 knockout (Cdc42mye) and Cdc42flox mice. Myeloid-derived macrophages were traced with RosamTmG fluorescent reporter under LyzCre-mediated excision. The experiments for serum or hepatic enzymic activities, histologic and immunologic analysis, gene expressions, flow cytometry analysis, and cytokine antibody array were performed. RESULTS: Myeloid deletion of Cdc42 significantly alleviated hepatic damages with the reduction of hepatic necrosis and inflammation, and reserved hepatic functions following HIRI in mice. Myeloid Cdc42 deficiency suppressed the infiltration of myeloid macrophages, reduced the secretion of proinflammatory cytokines, restrained M1 polarization, and promoted M2 polarization of myeloid macrophages in livers. In addition, inactivation of Cdc42 promoted M2 polarization via suppressing the phosphorylation of STAT1 and promoting phosphorylation of STAT3 and STAT6 in myeloid macrophages. Furthermore, pretreatment with Cdc42 inhibitor, ML141, also protected mice from hepatic ischemia-reperfusion injury. CONCLUSIONS: Inhibition or deletion of myeloid Cdc42 protects liver from HIRI via restraining the infiltration of myeloid macrophages, suppressing proinflammatory response, and promoting M2 polarization in macrophages.


Assuntos
Modelos Animais de Doenças , Inflamação , Fígado , Macrófagos , Camundongos Knockout , Traumatismo por Reperfusão , Proteína cdc42 de Ligação ao GTP , Animais , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/prevenção & controle , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteína cdc42 de Ligação ao GTP/genética , Camundongos , Macrófagos/metabolismo , Macrófagos/imunologia , Fígado/patologia , Fígado/metabolismo , Fígado/imunologia , Inflamação/patologia , Inflamação/metabolismo , Células Mieloides/metabolismo , Células Mieloides/patologia , Fator de Transcrição STAT3/metabolismo , Masculino , Fator de Transcrição STAT1/metabolismo , Citocinas/metabolismo , Fator de Transcrição STAT6/metabolismo , Fator de Transcrição STAT6/genética , Fator de Transcrição STAT6/deficiência , Camundongos Endogâmicos C57BL , Deleção de Genes
2.
Epigenetics Chromatin ; 16(1): 44, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37941029

RESUMO

BACKGROUND: In a heterogeneous population of cells, individual cells can behave differently and respond variably to the environment. This cellular diversity can be assessed by measuring DNA methylation patterns. The loci with variable methylation patterns are informative of cellular heterogeneity and may serve as biomarkers of diseases and developmental progression. Cell-to-cell methylation heterogeneity can be evaluated through single-cell methylomes or computational techniques for pooled cells. However, the feasibility and performance of these approaches to precisely estimate methylation heterogeneity require further assessment. RESULTS: Here, we proposed model-based methods adopted from a mathematical framework originally from biodiversity, to estimate genome-wide DNA methylation heterogeneity. We evaluated the performance of our models and the existing methods with feature comparison, and tested on both synthetic datasets and real data. Overall, our methods have demonstrated advantages over others because of their better correlation with the actual heterogeneity. We also demonstrated that methylation heterogeneity offers an additional layer of biological information distinct from the conventional methylation level. In the case studies, we showed that distinct profiles of methylation heterogeneity in CG and non-CG methylation can predict the regulatory roles between genomic elements in Arabidopsis. This opens up a new direction for plant epigenomics. Finally, we demonstrated that our score might be able to identify loci in human cancer samples as putative biomarkers for early cancer detection. CONCLUSIONS: We adopted the mathematical framework from biodiversity into three model-based methods for analyzing genome-wide DNA methylation heterogeneity to monitor cellular heterogeneity. Our methods, namely MeH, have been implemented, evaluated with existing methods, and are open to the research community.


Assuntos
Metilação de DNA , Neoplasias , Humanos , Genoma , Análise de Sequência de DNA/métodos , DNA , Neoplasias/genética , Biomarcadores
3.
Virus Res ; 336: 199209, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37633596

RESUMO

Classical swine fever virus (CSFV) shares high antigenic homology with other members of the genus Pestivirus. Because several pestivirus species can also infect swine, eliciting cross-reactive antibodies, it is important to define CSFV-specific epitopes for the differential diagnosis of classical swine fever (CSF) by serology. For this purpose, epitope mapping of seven monoclonal antibodies (mAbs), recognizing sites on the D/A domain of glycoprotein E2, was performed using recombinant expressed antigenic domains and mutants of E2, as well as an overlapping peptide library. Three CSFV-specific epitopes, i.e., 780-IEEMGDDFGFGLCPF-794, 810-NGSAFYLVCPIGWTG-824, and 846-REKPF-850, were identified within the D/A domain of E2. Site-directed mutagenesis further confirmed that residues 783-MGD-785, 789-FGLCPF-794, 813-AFYLVCPIGWTG-824, and 846-REK-848 were critical residues in these regions. In addition, a F789S difference within the epitope 780-IEEMGDDFGFGLCPF-794 was responsible for the absence of binding of two mAbs to the E2 protein of the live attenuated CSFV vaccine strain Riems. Structural modeling revealed that, the three epitopes are located near each other, suggesting that they may form a more complex conformational epitope on the D/A domain in vivo. Six of the mAbs neutralized viruses of diverse genotypes, indicating that the target epitopes are involved in virus interaction with cells. The binding of CSFV to cells was significantly reduced after pre-incubation with either truncated E2 proteins comprising the D/A domain or with the CSFV-specific mAbs targeting the domain D/A. These epitopes identified on the D/A domain are important targets for virus neutralization that might be involved in the early steps of CSFV infection. These findings reveal potential candidates for improving the differential diagnosis of pestiviruses by serology.

4.
Oncol Rep ; 49(3)2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36660927

RESUMO

Hepatocellular carcinoma (HCC) represents almost 80% of all liver cancers, is the sixth most common cancer and is the second­highest cause of cancer­related deaths worldwide. Protein tyrosine phosphatases (PTPs), which are encoded by the largest family of phosphatase genes, play critical roles in cellular responses and are implicated in various signaling pathways. Moreover, PTPs are dysregulated and involved in various cellular processes in numerous cancers, including HCC. Kinases and phosphatases are coordinators that modulate cell activities and regulate signaling responses. There are multiple interacting signaling networks, and coordination of these signaling networks in response to a stimulus determines the physiological outcome. Numerous issues, such as drug resistance and inflammatory reactions in the tumor microenvironment, are implicated in cancer progression, and the role of PTPs in these processes has not been well elucidated. Therefore, the present review focused on discussing the relationship of PTPs with inflammatory cytokines and chemotherapy/targeted drug resistance, providing detailed information on how PTPs can modulate inflammatory reactions and drug resistance to influence progression in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Proteínas Tirosina Fosfatases/genética , Proteínas Tirosina Fosfatases/metabolismo , Transdução de Sinais/genética , Inflamação , Microambiente Tumoral
5.
Toxicol In Vitro ; 86: 105511, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36336209

RESUMO

Chronic exposure of skin to ultraviolet (UV) radiation is responsible for skin ageing, which includes degradation of the epidermal and dermal layers. Filtering UV light is key in the sunscreen industry. We studied the effects of organic UV filters on hyaluronan (HA) metabolism and skin hydration in human HaCaT keratinocytes. The gene expression of HA receptors, HA synthase (HAS), hyaluronidase (HYAL), and water channel aquaporin 3 (AQP3) was evaluated by quantitative RT-PCR. The state of oxidative stress was determined by measuring the intracellular levels of reactive oxygen species (ROS). The results showed that five organic UV filters reduced the extracellular contents of HA, and a phosphatidylinositol 3-kinase (PI3K) inhibitor partially restored the decreased HA levels after octinoxate, octocrylene, and oxybenzone treatment. The expression levels of HA receptors, including cluster of differentiation 44 (CD44), receptor for hyaluronic acid-mediated motility (RHAMM), and toll-like receptors (TLRs), were determined. Avobenzone, octinoxate, oxybenzone, and padimate O exerted inhibitory effects on RHAMM expression. Oxybenzone led to a significant increase in CD44 and AQP3 expression. Both octinoxate and octocrylene increased TLR4 expression but decreased ROS accumulation by activating the PI3K pathway. However, the organic UV filters differentially regulated the mRNA expression of HAS and HYAL. Taken together, these results suggest that certain organic UV filters regulate HA metabolism in human keratinocytes in a PI3K pathway-dependent manner.


Assuntos
Ácido Hialurônico , Fosfatidilinositol 3-Quinase , Humanos , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Queratinócitos , Raios Ultravioleta , Hialuronoglucosaminidase/metabolismo
6.
Int J Biol Macromol ; 209(Pt A): 506-512, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35398387

RESUMO

Gum Arabic, a mixture of polysaccharide and glycoprotein, is used as an emulsifying stabilizer in the food industry. It might have immunomodulatory effects. We hypothesized that the combination of IFN-γ and Gum Arabic promotes the production of pro-inflammatory factors in RAW 264.7 cells. Treatment of RAW 264.7 cells with the combination of 3% Gum Arabic and 40 ng/mL IFN-γ resulted in a drastic increase (320%) in nitric oxide production compared with that induced by IFN-γ alone. PGE-2 was produced after the cells were treated with 3% Gum Arabic and 40 ng/mL IFN-γ for 6 h. Gum Arabic and IFN-γ increased the production of iNOS and COX-2 proteins, and triggered TNF-α release. Apart from TNF-α, the release of both G-CSF and IL-6 increased by more than 100 times. The release of IL-3, RANTES, and IL-10 increased by more than ten times. Gum Arabic and IFN-γ also increased the secretion of IL-10, IL-1α, IL-1ß, IL-13, KC, IL-5, IL-4, IL-12, Eotaxin, IL-9, MCP-1, and ROS. Cytokines associated with M1 polarization of macrophages such as TNF-α, IL-1ß, IL-12, NO, and ROS were induced by Gum Arabic and IFN-γ. Our findings help to explore the inflammatory reaction caused by Gum Arabic in cosmetics.


Assuntos
Interleucina-10 , Fator de Necrose Tumoral alfa , Citocinas/metabolismo , Goma Arábica/farmacologia , Interferon gama/metabolismo , Interferon gama/farmacologia , Interleucina-10/metabolismo , Interleucina-12/metabolismo , Macrófagos , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
7.
Mol Metab ; 60: 101473, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35292404

RESUMO

OBJECTIVE: Abdominal adiposity is strongly associated with diabetic and cardiovascular comorbidities. The long noncoding RNA HOTAIR (HOX Transcript Antisense Intergenic RNA) is an important epigenetic regulator with fat depot-specific expression. Its functional roles and epigenetic regulation in abdominal adipogenesis remain uncertain. METHODS: We collected different fat depots from healthy, severely obese, and uraemic subjects to measure fat-depot specific gene expression and quantify regional adiposity via dual-energy X-ray absorptiometry (DXA). HOTAIR was overexpressed to evaluate its functional roles. Reduced representation bisulfite sequencing (RRBS), RNA-sequencing, real-time qPCR and RNA/chromatin immunoprecipitation were performed to analyse HOTAIR-mediated epigenetic regulation. RESULTS: A negative correlation between adipose tissue HOTAIR expression (arm or abdominal subcutaneous fat depots) and regional adiposity under the status of severe obesity or uraemia was observed. HOTAIR overexpression using human immortalized abdominal preadipocytes further revealed its anti-adipogenic effects. Integrative analysis of genome-wide DNA methylation by reduced representation bisulfite sequencing (RRBS) and gene expression was performed. Overall, the differentially methylated genes were functionally enriched for nervous system development, suggesting that HOTAIR may be epigenetically associated with cell lineage commitment. We specifically found that HOTAIR-mediated genes showed strong changes in both DNA methylation and gene expression during abdominal adipogenesis. We observed that two HOTAIR-repressed genes, SLITRK4 and PITPNC1, present an obesity-driven fat-depot specific expression pattern that is positively correlated with the central body fat distribution. CONCLUSIONS: Our study indicated that HOTAIR is a key regulator of abdominal adipogenesis via intricate DNA methylation and is likely to be associated with the transcriptional regulation of genes involved in nervous system development and lipid metabolism, such as SLITRK4 and PITPNC1.


Assuntos
Adipogenia , Metilação de DNA , Adipogenia/genética , Tecido Adiposo/metabolismo , Metilação de DNA/genética , Epigênese Genética/genética , Humanos , Proteínas de Membrana/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Obesidade/genética , Obesidade/metabolismo , RNA Longo não Codificante
8.
Psychol Res ; 86(3): 844-857, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34097132

RESUMO

In recent years, research on interoceptive abilities (i.e., sensibility, accuracy, and awareness) and their associations with emotional experience has flourished. Yet interoceptive abilities in alexithymia-a personality trait characterized by a difficulty in the cognitive interpretation of emotional arousal, which impacts emotional experience-remain under-investigated, thereby limiting a full understanding of subjective emotional experience processing. Research has proposed two contrasting explanations thus far: in one model, the dimensions of interoceptive sensibility and accuracy in alexithymia would increase; in the other model, they would decrease. Surprisingly, the contribution of interoceptive awareness has been minimally researched. In this study (N = 182), the relationship between participants' level of alexithymia and the three interoceptive dimensions was tested. Our results show that the higher the level of alexithymia is, the higher interoceptive accuracy and sensibility (R2 = 0.29 and R2 = 0.14); conversely, the higher the level of alexithymia is, the lower interoceptive awareness (R2 = 0.36). Moreover, an ROC analysis reveals that interoceptive awareness is the most accurate predictor of alexithymia, yielding over 92% accuracy. Collectively, these results support a coherent understanding of interoceptive abilities in alexithymia, whereby the dissociation of interoceptive accuracy and awareness may explain the underlying psycho-physiological mechanisms of alexithymia. A possible neurocognitive mechanism is discussed which suggests insurgence of psychosomatic disorders in alexithymia and related psychotherapeutic approaches.


Assuntos
Sintomas Afetivos , Emoções , Sintomas Afetivos/psicologia , Nível de Alerta , Transtornos Dissociativos , Emoções/fisiologia , Humanos
9.
Helicobacter ; 26(6): e12857, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34708471

RESUMO

BACKGROUND: Probiotics may alter the gut microbiota and may reduce antibiotic-related dysbiosis after H. pylori eradication. However, whether probiotics are effective in reducing the bacterial load of H. pylori and modifying the gut microbiota remains unknown. We aimed to assess the efficacy of Lactobacillus acidophilus and Lactobacillus rhamnosus in reducing the bacterial load of H. pylori and modifying the gut microbiota. MATERIALS AND METHODS: In this double-blind, randomized, placebo-controlled trial, we recruited 40 adult subjects with moderate to high bacterial loads of H. pylori, defined as a mean delta over baseline (DOB) value of the 13 C-urea breath test (13 C-UBT) of 10 or greater every 4 days 6 times. Eligible subjects were randomized in a 1:1 ratio to receive either probiotics containing Lactobacillus acidophilus and Lactobacillus rhamnosus or placebo twice daily for 4 weeks. 13 C-UBT was measured weekly from the beginning of treatment to 2 weeks after treatment. Amplification of the V3 and V4 hypervariable regions of the 16S rRNA was performed for fecal microbiota. RESULTS: A total of 40 subjects were randomized to receive probiotics or placebo. The DOB value was significantly lower in the probiotic group than in the placebo group after 4 weeks of treatment (26.0 vs. 18.5, p = .045). The DOB value was significantly reduced compared to that at baseline in the probiotic group (18.5 vs. 26.7, p = .001) but not in the placebo group (26.0 vs. 25.0, p = .648). However, the eradication rate for H. pylori was 0% in both groups. There was no significant difference in the DOB values between the two groups 1 and 2 weeks after discontinuation of the probiotics. There were also no significant changes observed in the α-diversity and ß-diversity at week 4 compared to baseline in the probiotic group (p = .77 and 0.91) and the placebo group (p = .26 and 0.67). CONCLUSIONS: Although the use of Lactobacillus acidophilus and Lactobacillus rhamnosus may reduce the bacterial load of H. pylori, there were no significant changes in the composition of gut microbiota. This trial is registered with ClinicalTrials.gov, NCT02725138.


Assuntos
Microbioma Gastrointestinal , Infecções por Helicobacter , Helicobacter pylori , Probióticos , Adulto , Carga Bacteriana , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/prevenção & controle , Humanos , Lactobacillus acidophilus , RNA Ribossômico 16S/genética
10.
Viruses ; 13(8)2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34452520

RESUMO

Classical swine fever virus (CSFV) shares high structural and antigenic homology with bovine viral diarrhea virus (BVDV) and border disease virus (BDV). Because all three viruses can infect swine and elicit cross-reactive antibodies, it is necessary to differentiate among them with regard to serological diagnosis of classical swine fever. To understand the mechanism of cross-reactivity, it is important to define common or specific epitopes of these viruses. For this purpose, epitope mapping of six monoclonal antibodies (mAbs) was performed using recombinant expressed antigenic domains of CSFV and BDV E2 proteins. One CSFV-specific conformational epitope and one CSFV and BDV common epitope within domain B/C of E2 were identified. Site-directed mutagenesis confirmed that residues G725 and V738/I738 of the CSFV-specific epitope and P709/L709 and E713 of the second epitope are important for mAbs binding. Infection of CSFV in porcine cells was significantly reduced after pre-incubation of the cells with the domain B/C of E2 or after pre-incubation of CSFV with the mAbs detecting domain B/C. 3D structural modeling suggested that both epitopes are exposed on the surface of E2. Based on this, the identified epitopes represent a potential target for virus neutralization and might be involved in the early steps of CSFV infection.


Assuntos
Doença da Fronteira/virologia , Vírus da Doença da Fronteira/imunologia , Vírus da Febre Suína Clássica/imunologia , Peste Suína Clássica/virologia , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/imunologia , Animais , Vírus da Doença da Fronteira/química , Vírus da Doença da Fronteira/genética , Vírus da Febre Suína Clássica/química , Vírus da Febre Suína Clássica/genética , Mapeamento de Epitopos , Epitopos/química , Epitopos/genética , Epitopos/imunologia , Domínios Proteicos , Suínos , Doenças dos Suínos/virologia , Proteínas do Envelope Viral/genética
11.
Molecules ; 26(12)2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34204643

RESUMO

Plant-derived protein hydrolysates have potential applications in nutrition. Rice protein hydrolysates (RPHs), an excellent source of proteins, have attracted attention for the development of cosmeceuticals. However, few studies have reported the potential application of RPH in analysis, and this study examined their antioxidant activities and the inhibitory activities of skin aging enzymes. The results indicated that the total phenolic and flavonoid concentrations were 2.06 ± 0.13 mg gallic acid equivalent/g RPHs and 25.96 ± 0.52 µg quercetin equivalent/g RPHs, respectively. RPHs demonstrated dose-dependent activity for scavenging free radicals from 1,1-diphenyl-2-picrylhydrazyl [half-maximal inhibitory concentration (IC50) = 42.58 ± 2.1 mg/g RPHs] and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (IC50 = 2.11 ± 0.88 mg/g RPHs), dose-dependent reduction capacity (6.95 ± 1.40 mg vitamin C equivalent/g RPHs) and oxygen radical absorbance capacity (473 µmol Trolox equivalent/g RPHs). The concentrations of the RPH solution required to achieve 50% inhibition of hyaluronidase and tyrosinase activities were determined to be 8.91 and 107.6 mg/mL, respectively. This study demonstrated that RPHs have antioxidant, antihyaluronidase, and antityrosinase activities for future cosmetic applications.


Assuntos
Hidrolisados de Proteína/química , Hidrolisados de Proteína/farmacologia , Envelhecimento/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Clareadores/química , Clareadores/metabolismo , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Ácido Gálico/farmacologia , Camundongos , Oryza/química , Oryza/enzimologia , Oryza/metabolismo , Oxirredução , Fenóis/farmacologia , Picratos/química , Picratos/farmacologia , Extratos Vegetais/química , Quercetina/farmacologia , Células RAW 264.7 , Ácidos Sulfônicos/química , Ácidos Sulfônicos/farmacologia , Tiazóis/química , Tiazóis/farmacologia
12.
Micromachines (Basel) ; 12(5)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062908

RESUMO

Efficient heat removal through the substrate is required in high-power operation of AlGaN/GaN high-electron-mobility transistors (HEMTs). Thus, a SiC substrate was used due to its popularity. This article reports the electrical characteristics of normally off p-GaN gate AlGaN/GaN high-electron-mobility transistors (HEMTs) on a low-resistivity SiC substrate compared with the traditional Si substrate. The p-GaN HEMTs on the SiC substrate possess several advantages, including electrical characteristics and good qualities of epitaxial crystals, especially on temperature performance. Additionally, the price of the low-resistivity SiC substrate is three times lower than the ordinary SiC substrate.

13.
Eur J Med Chem ; 201: 112422, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32569926

RESUMO

P-Glycoprotein (P-gp) overexpression is a major mechanism by which cancer cells acquire the multidrug resistance (MDR) phenotype, and is associated with poor clinical outcome in patients. In an effort to develop MDR-reversal agents, we synthesized and evaluated a series of thiophenylbenzofuran derivatives (4-31) as P-gp inhibitors, among which compounds 4, 10, and 14 represented the optimal agent in reversing the MDR phenotype. These P-gp inhibitors were dramatically effective than verapamil in sensitizing the human ABCB1-overexpressing ABCB1/Flp-In™-293 cells and MDR KBvin cells to a series of chemotherapeutic agents, including vincristine and paclitaxel, as manifested by multi-fold decreases in the respective IC50 values to therapeutically attainable levels.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Benzofuranos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Benzofuranos/síntese química , Benzofuranos/metabolismo , Sítios de Ligação , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligação Proteica
14.
Front Microbiol ; 11: 616922, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33552027

RESUMO

DNA methyltransferases (DNMTs) are a group of proteins that catalyze DNA methylation by transferring a methyl group to DNA. The genetic variation in DNMTs results in differential DNA methylation patterns associated with various biological processes. In fungal species, DNMTs and their DNA methylation profiles were found to be very diverse and have gained many research interests. We reviewed fungal DNMTs in terms of their biological functions, protein domain structures, and their associated epigenetic regulations compared to those known in plant and animal systems. In addition, we summarized recent reports on potential RNA-directed DNA methylation (RdDM) related to DNMT5 in fungi. We surveyed up to 40 fungal species with published genome-wide DNA methylation profiles (methylomes) and presented the associations between the specific patterns of fungal DNA methylation and their DNMTs based on a phylogenetic tree of protein domain structures. For example, the main DNMTs in Basidiomycota, DNMT1 with RFD domain + DNMT5, contributing to CG methylation preference, were distinct from RID + Dim-2 in Ascomycota, resulting in a non-CG methylation preference. Lastly, we revealed that the dynamic methylation involved in fungal life stage changes was particularly low in mycelium and DNA methylation was preferentially located in transposable elements (TEs). This review comprehensively discussed fungal DNMTs and methylomes and their connection with fungal development and taxonomy to present the diverse usages of DNA methylation in fungal genomes.

15.
Phytother Res ; 33(4): 1104-1113, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30734961

RESUMO

Myrica rubra Sieb. et Zucc. (Myricaceae), known as Chinese bayberry, is traditionally used as folk medicine in Asian countries. The interaction of Propionibacterium acnes signalling with sebocytes is considered important in the pathogenesis of acne. In the present study, extracts and active compounds of Chinese bayberry were used to determine chemical antioxidant activity and anti-inflammatory effects in P. acnes-stimulated human SZ95 sebocytes. A high-performance liquid chromatography with electrochemical detection system was used to analyse the phenolic composition of bayberry extracts. Accordingly, the flavonols, myricitrin and myricetin, were found to be abundant in the unhydrolysed and hydrolysed extracts of Chinese bayberry fruits, respectively. The anthocyanin cyanidin-3-glucoside was also predominantly found in the unhydrolysed extracts. Quantification of human inflammatory cytokines indicated that cell-free extracts of P. acnes stimulated IL-8 and IL-6 production, which was inhibited by myricetin, rather than its glycoside or anthocyanin. Myricetin also exhibited inhibitory effects in P. acnes-stimulated gene expression of Toll-like receptor (TLR) 2 and protein phosphorylation of p70 S6 kinase. In conclusion, myricetin shows a suppressive effect on P. acnes-induced cytokine production through regulation of the TLR and mammalian target of rapamycin pathways. Myricetin goes beyond previous research findings to potentially modulate inflammatory signalling in human sebocytes. These results will be valuable in developing anti-inflammatory agents against skin acne.


Assuntos
Citocinas/efeitos dos fármacos , Flavonoides/uso terapêutico , Myrica/química , Extratos Vegetais/química , Propionibacterium acnes/efeitos dos fármacos , Medicamentos de Ervas Chinesas , Flavonoides/farmacologia , Humanos , Extratos Vegetais/farmacologia
16.
Surg Endosc ; 32(11): 4472-4480, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29717372

RESUMO

BACKGROUND: Few clear recommendations exist for the management of colorectal anastomotic leaks, often based on surgeon preferences or institutional protocols. The primary goal was to evaluate the feasibility and safety of the combined laparoscopic and transanal (hybrid) approach to treat postoperative colorectal anastomotic leaks. The secondary goals included comparison of outcomes following early (< 5 days after initial resection) versus late (≥ 5 days) detection of leaks. MATERIALS AND METHODS: Sixteen hemodynamically stable patients, with anastomotic dehiscence < 50% of the circumference after laparoscopic anterior resection underwent repeat laparoscopy (lavage/drainage) and transanal endolumenal repair (7 low (< 5 cm from the anal verge) with an ordinary anoscope and 9 high (≥ 5 cm from the anal verge) with a transanal endoscopic operations (TEO®) platform). RESULTS: The median delay to detection and management was 4.5 days. The procedure was feasible in 13/16 patients (3 patients required conversion to laparotomy). Primary healing of the anastomosis was obtained in 14 patients (13 with the combined procedure, one after conversion). Two patients (1 early, 1 late) sustained persistent purulent discharge via their drain, but the repair healed secondarily. All patients requiring conversion to laparotomy (n = 3) or sustaining intra-operative complications (n = 3) were in the delayed group. No patients required further intervention or died. Protective stomas, created either at index surgery (n = 7) or at re-operation (n = 9), were closed in 14/16 patients within 6 months and no anastomotic sinus, persistent or recurrent fistula, was noted at 1-year follow-up. LIMITATIONS: This is a single-center study consisting of small sample size. CONCLUSIONS: Combined repeat laparoscopy and transanal endolumenal repair is feasible and safe, potentially reducing postoperative morbidity associated with repeat laparotomy and anastomotic leaks. Early detection and re-intervention are fundamental to success. Currently missing from the International Study Group of Rectal Cancer recommendations, laparoscopy and endolumenal repair could be added as a therapeutic option in Grade B.


Assuntos
Fístula Anastomótica/cirurgia , Neoplasias Colorretais/cirurgia , Laparoscopia/métodos , Cirurgia Endoscópica por Orifício Natural/métodos , Neoplasias Retais/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Canal Anal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Resultado do Tratamento
17.
Int J Biol Macromol ; 114: 181-186, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29572144

RESUMO

Locust bean gum (LBG) galactomannan has been claimed to have applications in the biopharmaceutical field. However, the effects of LBG galactomannan on immunomodulatory aspects are not yet clear. The purpose of this study was to over-express thermostable ß-d-mannanase from the thermophilic actinomycete Thermobifida fusca BCRC 19214 using a Pichia pastoris expression system. The maximum intracellular ß-d-mannanase activity obtained from the cell-free extract was approximately 40.0U/mL after 72h of cultivating a P. pastoris transformant (pPICZ-man) induced with methanol. Hydrolysis of native LBG galactomannan with 8U/mL ß-d-mannanase for 24h significantly decreased the weight-average molecular weight of LBG galactomannan from 5,580,010 to 3188. Native and hydrolyzed LBG galactomannan in a range of 0-0.2% did not trigger significant cytotoxicity after 24h of treatment compared with the control. The native LBG galactomannan stimulated RAW 264.7 cells to produce cytokine TNF-α dose-dependently, but there was no significant IL-1ß or nitric oxide production. The native LBG galactomannan also stimulated ß-hexosaminidase secretion in RBL-2H3 cells. After the native LBG galactomannan was hydrolyzed with ß-d-mannanase, all of the immunological properties disappeared. These results suggest the possible immunomodulatory effects of native LBG galactomannan.


Assuntos
Actinomyces/enzimologia , Proteínas Fúngicas/química , Galactanos/química , Interleucina-1beta/metabolismo , Mananas/química , Óxido Nítrico/metabolismo , Gomas Vegetais/química , Fator de Necrose Tumoral alfa/metabolismo , beta-Manosidase/química , Actinomyces/genética , Animais , Proteínas Fúngicas/genética , Galactose/análogos & derivados , Hidrólise , Mananas/farmacologia , Camundongos , Células RAW 264.7 , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , beta-Manosidase/genética
18.
Dis Colon Rectum ; 60(1): 43-50, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27926556

RESUMO

BACKGROUND: Double and triple stapling techniques to close the rectal stump in laparoscopic anterior resection are fraught with technical drawbacks that could possibly be avoided with the use of the single stapling technique. However, little is known of its safety in laparoscopic surgery or outcomes when combined with natural orifice specimen extraction. OBJECTIVE: This study aims to analyze the feasibility and the operative and immediate postoperative outcomes of single-stapled anastomosis and natural orifice specimen extraction with conventional techniques. It intends to evaluate technical variations related to colon, mesentery, and pelvic anatomy characteristics. DESIGN AND PATIENTS: A consecutive series of 188 patients underwent elective surgery for benign or malignant lesions between 10 and 40 cm from the anal verge, 5 cm or less in diameter on radiological examination, stage T1 to T3, Nx, M0, with 2 different methods of rectal stump closure (pursestring vs linear-stapled closure) associated with single or double stapling and per anus vs conventional specimen extraction. SETTING: This study was conducted at China Medical University Hospital, Taiwan, a tertiary referral center, between January 2012 and April 2015. MAIN OUTCOME MEASURES: The main outcomes measured are feasibility and operative and immediate postoperative outcomes. RESULTS: Single-stapled resection with natural orifice specimen extraction was feasible in 94% patients with an 11% perioperative morbidity rate. The patients required statistically significantly less analgesia, had earlier return of bowel movements, and shorter hospital stay, whereas there was no statistically significant difference in the overall readmission rate and overall morbidity, including anastomotic leakage. LIMITATIONS: This was a single-center, retrospective case-matched study. CONCLUSION: Anatomic variations (short colon and short mesentery) can be managed adequately with intracorporeal anvil head fixation. The single stapling technique is feasible and as safe as conventional double stapling techniques, although it is technically more demanding. The transanal endoscopic operation platform can be useful when the rectal stump is long.


Assuntos
Anastomose Cirúrgica/métodos , Fístula Anastomótica/epidemiologia , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Neoplasias Retais/cirurgia , Grampeamento Cirúrgico/métodos , Idoso , Estudos de Casos e Controles , China , Estudos de Viabilidade , Feminino , Humanos , Laparoscopia , Tempo de Internação , Masculino , Mesentério/cirurgia , Pessoa de Meia-Idade , Cirurgia Endoscópica por Orifício Natural , Reto/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
19.
Anticancer Res ; 36(11): 6155-6160, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27793945

RESUMO

BACKGROUND/AIM: Capecitabine is the current standard oral chemotherapy used in neoadjuvant concurrent chemoradiotherapy (NCCRT) for locally advanced rectal cancer (LARC) in North America. We compared the effectiveness of another oral chemotherapy agent, UFT (an oral combination of uracil and tegafur), to that of capecitabine. MATERIALS AND METHODS: We identified LARC patients diagnosed from 2007 to 2011 using a population-based registry in Taiwan (Health and Welfare Data Science Center, HWDC) and constructed a propensity score matched cohort to balance observable potential confounders. We compared the hazard ratio (HR) of death between the UFT and capecitabine groups. We performed supplementary analysis (SA) to evaluate the robustness of our finding regarding potential unobserved confounders (SA-1) and the robustness of the result in a subgroup when an additional potential confounder was taken into account (SA-2). RESULTS: Our study population comprised of 200 patients balanced with respect to observed co-variables. UFT lowered the hazard of death significantly more than capecitabine (HR=0.58, 95% confidence interval (CI)=0.35-0.95, p=0.03). Our result was moderately sensitive in SA-1 but not significant in SA-2. CONCLUSION: The effectiveness of UFT in NCCRT for LARC is probably non-inferior to that of capecitabine.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Retais/tratamento farmacológico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Capecitabina/administração & dosagem , Quimioterapia Adjuvante , Feminino , Humanos , Masculino , Indução de Remissão , Taxa de Sobrevida , Tegafur/administração & dosagem , Uracila/administração & dosagem
20.
Int J Biol Macromol ; 82: 1-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26476245

RESUMO

Native konjac glucomannan was used as the substrate for thermophilic actinomycetes, Thermobifida fusca BCRC19214, to produce ß-mannanase. The ß-mannanase was purified and five internal amino acid sequences were determined by LC-MS/MS. These sequences had high homology with the ß-mannanase from T. fusca YX. The tfm gene which encoded the ß-mannanase was cloned, sequenced and heterologous expressed in Yarrowia lipolytica P01 g expression system. Recombinant heterologous expression resulted in extracellular ß-mannanase production at levels as high as 3.16 U/ml in the culture broth within 48 h cultivation. The recombinant ß-mannanase from Y. lipolytica transformant had superior thermal property. The optimal temperature of the recombinant ß-mannanase from Y. lipolytica transformant (pYLSC1-tfm) was 80°C. When native konjac glucomannan was incubated with the recombinant ß-mannanase from Y. lipolytica transformant (pYLSC1-tfm) at 50°C, there was a fast decrease of viscosity happen during the initial phase of reaction. This viscosity reduction was accompanied by an increase of reducing sugars. The surface of konjac glucomannan film became smooth. After 24h of treatment, the DPw of native konjac glucomannan decreased from 6,435,139 to 3089.


Assuntos
Mananas/química , Leveduras/enzimologia , beta-Manosidase/química , Ativação Enzimática , Estabilidade Enzimática , Fermentação , Hidrólise , Proteínas Recombinantes/química , Temperatura , Leveduras/genética , beta-Manosidase/biossíntese , beta-Manosidase/isolamento & purificação
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