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1.
Ann Surg Treat Res ; 106(6): 330-336, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38868581

RESUMO

Purpose: Managing recurrent inguinal hernias is complex, and choosing the right surgical approach (laparoscopic vs. open) is vital for patient outcomes. This study compared the outcomes of using the same vs. different surgical approaches for initial and subsequent hernia repairs. Methods: We retrospectively analyzed patients who underwent recurrent inguinal hernia repair at Seoul National University Bundang Hospital between January 2014 and May 2023. Patients were divided into the "concordant" and "discordant" groups, comprising patients who underwent same and different approaches in both surgeries, respectively. Preoperative baseline characteristics, index surgery data, postoperative outcomes, and recurrence rates were analyzed and compared. Results: In total, 131 patients were enrolled; the concordant and discordant groups comprised 31 (open, n = 19; laparoscopic, n = 12) and 100 patients (open to laparoscopic, n = 68; laparoscopic to open, n = 32), respectively. No significant differences were observed in the mean operation time (50.5 ± 21.7 minutes vs. 50.2 ± 20.0 minutes, P = 0.979), complication rates (6.5% vs. 14.0%, P = 0.356), or 36-month cumulative recurrence rates (9.8% vs. 9.8%; P = 0.865). The mean postoperative hospital stay was significantly shorter in the discordant than in the concordant group (1.8 ± 0.7 vs. 1.4 ± 0.6, P = 0.003). Conclusion: Most recurrent inguinal hernia repairs were performed using the discordant surgical approach. Overall, concordance in the surgical approach did not significantly affect postoperative outcomes. Therefore, the selection of the surgical approach based on the patient's condition and surgeon's preference may be advisable.

2.
mSphere ; 9(1): e0055723, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38085018

RESUMO

The N6-threonylcarbamoyl adenosine (t6A) tRNA modification is critical for ensuring translation fidelity across three domains of life. Our prior work highlighted the KEOPS complex, organized in a Pcc1-Kae1-Bud32-Cgi121 linear arrangement, not only serves an evolutionarily conserved role in t6A tRNA modification but also exerts diverse functional impacts on pathobiological characteristics in Cryptococcus neoformans, a leading cause of fungal meningitis worldwide. However, the extent to which the pleiotropic functions of the KEOPS complex are specifically tied to tRNA modification remains uncertain. To address this, we undertook a functional characterization of Sua5, responsible for generating the precursor threonylcarbamoyl-adenylate (TC-AMP) for t6A tRNA modification, using a reverse genetics approach. Comparative phenotypic analyses with KEOPS mutants revealed that Sua5 plays a vital role in multiple cellular processes, such as t6A tRNA modification, growth, sexual development, stress response, and virulence factor production, thus reflecting the multifaceted functions of the KEOPS complex. In support of this, sua5Δ bud32Δ double mutants showed phenotypes comparable to those of the corresponding single mutants. Intriguingly, a SUA5 allele lacking a mitochondria targeting sequence (SUA5MTSΔ) was sufficient to restore the wild-type phenotypes in the sua5Δ mutant, suggesting that Sua5's primary functional locus may be cytosolic, akin to the KEOPS complex. Further supporting this, the deletion of Qri7, a mitochondrial paralog of Kae1, had no discernible phenotypic impact on C. neoformans. We concluded that cytosolic t6A tRNA modifications, orchestrated by Sua5 and the KEOPS complex, are central to the regulation of diverse pathobiological functions in C. neoformans.IMPORTANCEUnderstanding cellular functions at the molecular level is crucial for advancing disease treatments. Our research reveals a critical connection between the KEOPS complex and Sua5 in Cryptococcus neoformans, a significant cause of fungal meningitis. While the KEOPS complex is known for its versatile roles in cellular processes, Sua5 is specialized in t6A tRNA modification. Our key finding is that the diverse roles of the KEOPS complex, ranging from cell growth and stress response to virulence, are fundamentally linked to its function in t6A tRNA modification. This conclusion is supported by the remarkable similarities between the impacts of Sua5 and KEOPS on these processes, despite their roles in different steps of the t6A modification pathway. This newfound understanding deepens our insight into fungal biology and opens new avenues for developing potential therapies against dangerous fungal diseases.


Assuntos
Cryptococcus neoformans , Meningite Fúngica , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , Adenosina/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo
3.
BMB Rep ; 56(2): 120-125, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36593106

RESUMO

Karyopherin-α3 (KPNA3), a karyopherin- α isoform, is intimately associated with metastatic progression via epithelial-mesenchymal transition (EMT). However, the molecular mechanism underlying how KPNA3 acts as an EMT inducer remains to be elucidated. In this report, we identified that KPNA3 was significantly upregulated in cancer cells, particularly in triple-negative breast cancer, and its knockdown resulted in the suppression of cell proliferation and metastasis. The comprehensive transcriptome analysis from KPNA3 knockdown cells indicated that KPNA3 is involved in the regulation of numerous EMTrelated genes, including the downregulation of GATA3 and E-cadherin and the up-regulation of HAS2. Moreover, it was found that KPNA3 EMT-mediated metastasis can be achieved by TGF-ß or AKT signaling pathways; this suggests that the novel independent signaling pathways KPNA3-TGF-ß-GATA3-HAS2/E-cadherin and KPNA3-AKT-HAS2/E-cadherin are involved in the EMT-mediated progress of TNBC MDA-MB-231 cells. These findings provide new insights into the divergent EMT inducibility of KPNA3 according to cell and cancer type. [BMB Reports 2023; 56(2): 120-125].


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , alfa Carioferinas , Feminino , Humanos , alfa Carioferinas/metabolismo , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Transição Epitelial-Mesenquimal , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo
4.
Biomacromolecules ; 23(12): 5193-5201, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36378752

RESUMO

With the continued advancement in the design and engineering of hydrogels for biomedical applications, there is a growing interest in imparting stimuli-responsiveness to the hydrogels in order to control their physicomechanical properties in a more programmable manner. In this study, an in situ forming hydrogel is developed by cross-linking alginate with an elastin-like polypeptide (ELP). Lysine-rich ELP synthesized by recombinant DNA technology is reacted with alginate presenting an aldehyde via Schiff base formation, resulting in facile hydrogel formation under physiological conditions. The physicomechanical properties of alginate-ELP hydrogels can be controlled in a wide range by the concentrations of alginate and ELP. Owing to the thermoresponsive properties of the ELP, the alginate-ELP hydrogels undergo swelling/deswelling near the physiological temperature. Taking advantage of these highly attractive properties of alginate-ELP, drug release kinetics were measured to evaluate their potential as a thermoresponsive drug delivery system. Furthermore, an ex vivo model was used to demonstrate the minimally invasive tissue injectability.


Assuntos
Elastina , Hidrogéis , Hidrogéis/química , Liberação Controlada de Fármacos , Elastina/química , Peptídeos/química , Temperatura , Cinética
5.
J Microbiol ; 60(7): 659-667, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35731347

RESUMO

Aptamers are short single-stranded DNA or RNA oligonucleotides capable of binding with high affinity and specificity to target molecules. Because of their durability and ease of synthesis, aptamers are used in a wide range of biomedical fields, including the diagnosis of diseases and targeted delivery of therapeutic agents. The aptamers were selected using a process called systematic evolution of ligands by exponential enrichment (SELEX), which has been improved for various research purposes since its development in 1990. In this protocol, we describe a modified SELEX method that rapidly produces high aptamer screening yields using two types of magnetic beads. Using this method, we isolated an aptamer that specifically binds to an antimicrobial peptide. We suggest that by conjugating a small therapeutic-specific aptamer to a gold nanoparticle-based delivery system, which enhances the stability and intracellular delivery of peptides, aptamers selected by our method can be used for the development of therapeutic agents utilizing small therapeutic peptides.


Assuntos
Aptâmeros de Nucleotídeos , Nanopartículas Metálicas , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Aptâmeros de Nucleotídeos/metabolismo , Ouro , Ligantes , Peptídeos , Técnica de Seleção de Aptâmeros/métodos
6.
Microb Pathog ; 165: 105460, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35231570

RESUMO

RNase E-mediated RNA processing and degradation are involved in bacterial adaptation to environmental changes. The RraA regulatory protein, which is highly conserved in γ-proteobacteria, differentially modulates RNase E activity. Recent studies have revealed the association of Salmonella enterica serovar Typhimurium RNase E (STRNase E) with bacterial pathogenicity; however, the molecular mechanisms are unknown. Here, we show that the expression levels of STRraA, a protein regulator of STRNase E activity, affect S. Typhimurium pathogenicity. RNA-sequencing and RT-PCR analyses indicated positive effects of STRraA levels on the abundance of mRNA species from class II flagellar operons. Primer extension analysis further identified STRraA-regulated STRNase E cleavage in the 5' untranslated region of fliDST mRNA. The cleavage affected the stability of this polycistronic mRNA, suggesting that STRraA protects fliDST mRNA from STRNase E cleavage, leading to enhanced flagellar assembly. Accordingly, STRraA positively regulated flagellar assembly and motility. In addition, STrraA-deleted cells showed decreased invasion ability and cytotoxicity in infection of human cervical epithelial carcinoma cells and reduced mortality in a mouse infection model compared to wild-type cells. These results support an active role of STRraA in RNase E-mediated modulation of pathogenesis in S. Typhimurium.


Assuntos
Regulação Bacteriana da Expressão Gênica , Salmonella typhimurium , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Endorribonucleases , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Virulência/genética
8.
J Microbiol ; 59(2): 113-123, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33527313

RESUMO

In recent years, the occurrence of antibiotic-resistant pathogens is increasing rapidly. There is growing concern as the development of antibiotics is slower than the increase in the resistance of pathogenic bacteria. Antimicrobial peptides (AMPs) are promising alternatives to antibiotics. Despite their name, which implies their antimicrobial activity, AMPs have recently been rediscovered as compounds having antifungal, antiviral, anticancer, antioxidant, and insecticidal effects. Moreover, many AMPs are relatively safe from toxic side effects and the generation of resistant microorganisms due to their target specificity and complexity of the mechanisms underlying their action. In this review, we summarize the history, classification, and mechanisms of action of AMPs, and provide descriptions of AMPs undergoing clinical trials. We also discuss the obstacles associated with the development of AMPs as therapeutic agents and recent strategies formulated to circumvent these obstacles.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Animais , Antibacterianos/química , Bactérias/crescimento & desenvolvimento , Infecções Bacterianas/microbiologia , Humanos , Proteínas Citotóxicas Formadoras de Poros/química
9.
Genes Dev ; 35(3-4): 286-299, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33446571

RESUMO

RNase E is an essential, multifunctional ribonuclease encoded in E. coli by the rne gene. Structural analysis indicates that the ribonucleolytic activity of this enzyme is conferred by rne-encoded polypeptide chains that (1) dimerize to form a catalytic site at the protein-protein interface, and (2) multimerize further to generate a tetrameric quaternary structure consisting of two dimerized Rne-peptide chains. We identify here a mutation in the Rne protein's catalytic region (E429G), as well as a bacterial cell wall peptidoglycan hydrolase (Amidase C [AmiC]), that selectively affect the specific activity of the RNase E enzyme on long RNA substrates, but not on short synthetic oligonucleotides, by enhancing enzyme multimerization. Unlike the increase in specific activity that accompanies concentration-induced multimerization, enhanced multimerization associated with either the E429G mutation or interaction of the Rne protein with AmiC is independent of the substrate's 5' terminus phosphorylation state. Our findings reveal a previously unsuspected substrate length-dependent regulatory role for RNase E quaternary structure and identify cis-acting and trans-acting factors that mediate such regulation.


Assuntos
Endorribonucleases/química , Endorribonucleases/metabolismo , Proteínas de Escherichia coli/química , Escherichia coli/enzimologia , Escherichia coli/genética , Modelos Moleculares , Amidoidrolases/metabolismo , Domínio Catalítico , Endorribonucleases/genética , Proteínas de Escherichia coli/genética , Mutação/genética , Estrutura Quaternária de Proteína , RNA Bacteriano/metabolismo , Regulação para Cima/genética
10.
EMBO J ; 39(24): e104719, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33215742

RESUMO

Recent evidence suggests that animal microRNAs (miRNAs) can target coding sequences (CDSs); however, the pathophysiological importance of such targeting remains unknown. Here, we show that a somatic heterozygous missense mutation (c.402C>G; p.C134W) in FOXL2, a feature shared by virtually all adult-type granulosa cell tumors (AGCTs), introduces a target site for miR-1236, which causes haploinsufficiency of the tumor-suppressor FOXL2. This miR-1236-mediated selective degradation of the variant FOXL2 mRNA is preferentially conducted by a distinct miRNA-loaded RNA-induced silencing complex (miRISC) directed by the Argonaute3 (AGO3) and DHX9 proteins. In both patients and a mouse model of AGCT, abundance of the inversely regulated variant FOXL2 with miR-1236 levels is highly correlated with malignant features of AGCT. Our study provides a molecular basis for understanding the conserved FOXL2 CDS mutation-mediated etiology of AGCT, revealing the existence of a previously unidentified mechanism of miRNA-targeting disease-associated mutations in the CDS by forming a non-canonical miRISC.


Assuntos
Proteína Forkhead Box L2/genética , Proteína Forkhead Box L2/metabolismo , Tumor de Células da Granulosa/genética , MicroRNAs/metabolismo , Mutação , Fases de Leitura Aberta , Desequilíbrio Alélico , Animais , Apoptose , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Morte Celular/fisiologia , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Inativação de Genes , Tumor de Células da Granulosa/patologia , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , MicroRNAs/genética , Mutação de Sentido Incorreto , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , RNA Mensageiro/metabolismo , Transcriptoma
11.
Nat Commun ; 11(1): 2010, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32332759

RESUMO

The balance between major DNA double-strand break (DSB) repair pathways is influenced by binding of the Ku complex, a XRCC5/6 heterodimer, to DSB ends, initiating non-homologous end joining (NHEJ) but preventing additional DSB end resection and homologous recombination (HR). However, the key molecular cue for Ku recruitment to DSB sites is unknown. Here, we report that FOXL2, a forkhead family transcriptional factor, directs DSB repair pathway choice by acetylation-dependent binding to Ku. Upon DSB induction, SIRT1 translocates to the nucleus and deacetylates FOXL2 at lysine 124, leading to liberation of XRCC5 and XRCC6 from FOXL2 and formation of the Ku complex. FOXL2 ablation enhances Ku recruitment to DSB sites, imbalances DSB repair kinetics by accelerating NHEJ and inhibiting HR, and thus leads to catastrophic genomic events. Our study unveils the SIRT1-(de)acetylated FOXL2-Ku axis that governs the balance of DSB repair pathways to maintain genome integrity.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA por Junção de Extremidades , Proteína Forkhead Box L2/metabolismo , Autoantígeno Ku/metabolismo , Acetilação , Linhagem Celular Tumoral , Proteína Forkhead Box L2/genética , Células HEK293 , Recombinação Homóloga , Humanos , Autoantígeno Ku/genética , Mutação , Ligação Proteica/genética , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sirtuína 1/metabolismo
12.
Vet Microbiol ; 225: 17-24, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30322527

RESUMO

The discovery of antimicrobial peptides (AMPs) in recent years has been promising for the treatment of multidrug resistant pathogenic microbes. Brucellosis is still considered one of the most common zoonoses in the world. In this study, we evaluated the effect HPA3P peptide in the bacterial uptake and intracellular growth of Brucella abortus (B. abortus) 544 in murine macrophages RAW 264.7. HPA3P was further utilized in a mouse model for infection and treatment. This peptide did not show cytotoxicity or bactericidal effect to B. abortus. However, it inhibited bacterial internalization at 0, 15 and 30 min incubation at two different doses at 12 and 24 µM as well as reduced intracellular growth after 2, 24 and 48 h incubation. Mice treated with HPA3P demonstrated a significant 1.01-log reduction (P < 0.0001) and spleen weight reduction compared to the nanocarrier control (P < 0.01). Significant increases in key cytokines Interferon-γ (IFN-γ) and Tumor necrosis factor (TNF) at 3, 7 and 14 days post-infection were observed in HPA3P treated mice similar to the antibiotic control group with both compared to the nanocarrier control. Monocyte chemoattractant protein-1 (MCP-1) was also heightened at 14 days post-infection. Histopathological analysis also suggests reduced bacterial granuloma in the liver and spleens of HPA3P treated group compared with the nanocarrier control group. In this study, the modulation of crucial cytokines IFN-γ and TNF might have led to a considerable reduction in the proliferation of B. abortus in a mouse model of brucellosis. Further investigation might be required to maximize the efficacy of HPA3P treatment in murine brucellosis.


Assuntos
Antibacterianos/farmacologia , Brucella abortus/efeitos dos fármacos , Brucelose/imunologia , Macrófagos/efeitos dos fármacos , Peptídeos/administração & dosagem , Peptídeos/farmacologia , Animais , Brucella abortus/crescimento & desenvolvimento , Brucella abortus/imunologia , Brucelose/microbiologia , Citocinas/imunologia , Modelos Animais de Doenças , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/farmacocinética , Interferon gama/imunologia , Fígado/microbiologia , Fígado/patologia , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Peptídeos/síntese química , Peptídeos/imunologia , Baço/microbiologia , Baço/patologia , Fator de Necrose Tumoral alfa/imunologia
13.
Int J Syst Evol Microbiol ; 68(9): 2755-2759, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30016233

RESUMO

A strictly aerobic, catalase-negative and oxidase-positive bacterium (HR-BBT), isolated from a water sample of the Han River, was taxonomically studied using a polyphasic approach. Cells were Gram-stain-negative motile rods with a polar flagellum. The strain grew at 20-35 °C and pH 7-8 and in the absence of NaCl. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain HR-BBT belonged to the family Nevskiaceae in the phylum Proteobacteria and formed a phylogenic lineage with members of the genus Solimonas. A comparison of the 16S rRNA gene sequences of strain HR-BBT and the type strains of closely related species of the genus Solimonas showed that it shared highest sequence similarity with Solimonas terrae KIS83-12T (94.9 %), Solimonas soli DCY12T (94.8 %), Solimonas variicoloris MN28T (94.4 %) and Solimonas flava CW-KD 4T (94.2 %). The fatty acids of the strain consisted of summed features 8 (comprising C18 : 1ω6c and/or C18 : 1ω7c) and 3 (comprising C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and C12 : 0 as major components. The polar lipids comprised phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, three unidentified phospholipids and an unidentified lipid. Ubiquinone-8 was detected as the sole respiratory quinone. The DNA G+C content of strain HR-BBT was 68.5 mol%. Based on the genotypic, chemotaxonomic and phenotypic analyses, strain HR-BBT represents a novel species of the genus Solimonas, for which the name Solimonas fluminis sp. nov. is proposed. The type strain is HR-BBT (=KACC 19410T=JCM 32268T).


Assuntos
Gammaproteobacteria/classificação , Filogenia , Rios/microbiologia , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Gammaproteobacteria/genética , Gammaproteobacteria/isolamento & purificação , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
14.
Oncogenesis ; 7(1): 3, 2018 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-29358688

RESUMO

Although endometrial cancer is the most common type of gynecological malignancy in developed countries, its molecular etiology is not well understood. Leucine-rich repeat and immunoglobulin-like domain 2 (LRIG2) is an evolutionarily conserved gene, but its functions in the endometrium are unknown. In this study, we found that LRIG2 is highly downregulated in endometrial adenocarcinoma patients and that it functions as a tumor suppressor. LRIG2 induced the mitochondrion-mediated apoptotic pathways by regulating stoichiometric balance among BCL-2 family proteins, whereby pro-survival members, MCL-1 and BCL-xL, were downregulated and pro-apoptotic BAK and BAX were upregulated. LRIG2 also inhibited proliferation of the Hec-1A and Ishikawa endometrial adenocarcinoma cells by upregulating p21. LRIG2 induced BAX- and BAK-dependent cell death that was efficiently prevented by MCL-1 overexpression. Furthermore, we found that LRIG2 unexpectedly phosphor-activates phosphoinositide 3-kinase (PI3K)/AKT and epidermal growth factor receptor (EGFR), which are conventionally accepted as survival signaling cues in diverse types of cancer. We observed that PI3K/AKT and EGFR serve as key kinases that have roles as growth suppressors of Hec-1A endometrial cancer cells by mediating the LRIG2-induced modulation of the BCL-2 family of proteins and p21. In vivo delivery of antisense DNAs against LRIG2 promoted the Hec-1A endometrial tumor growth in a xenograft mouse model, and immunoblotting of these tumor extracts showed consistent modulation of AKT, EGFR, the BCL-2 family members, and p21. Thus, our results demonstrated that LRIG2 is a growth suppressor of endometrial adenocarcinoma cells.

15.
Macromol Biosci ; 17(9)2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28691369

RESUMO

Hydrogels possess several physical and chemical properties suitable for engineering cellular environments for biomedical applications. Despite recent advances in hydrogel systems for cell culture, it is still a significant challenge to independently control the mechanical and diffusional properties of hydrogels, both of which are well known to influence various cell behaviors when using hydrogels as 3D cell culture systems. Controlling the crosslinking density of a hydrogel system to tune the mechanical properties inevitably affects their diffusional properties, as the crosslinking density and diffusion are often inversely correlated. In this study, a polymeric crosslinker is demonstrated that allows for the adjustment of the degree of substitution of reactive functional groups. By using this polymeric crosslinker, the rigidity of the resulting hydrogel is controlled in a wide range without changing the polymer concentration. Furthermore, their diffusional properties, as characterized by their swelling ratios, pore diameters, and drug release rates, are not significantly affected by the changes in the degree of substitution. 3D cell studies using this hydrogel system successfully demonstrate the varying effects of mechanical properties on different cell types, whereas those in a conventional hydrogel system are more significantly influenced by changes in diffusional properties.


Assuntos
Materiais Biocompatíveis/química , Engenharia Celular/métodos , Liberação Controlada de Fármacos , Hidrogéis/química , Células 3T3 , Animais , Difusão , Células Hep G2 , Humanos , Camundongos
16.
Biochem Biophys Res Commun ; 482(4): 877-882, 2017 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-27890615

RESUMO

Pituitary gonadotropins are key hormones that orchestrate the growth and development of ovarian follicles. However, limited information is available on intra-ovarian factors that mediate the actions of gonadotropins. In this study, we identified that the early growth response 2 gene (EGR2) is a gonadotropin-inducible gene in granulosa cells of rats and humans. Analysis of consensus EGR-binding elements (EBEs) showed that the immediate early response 3 gene (IER3) is a novel transcriptional target gene of EGR2 as confirmed by the luciferase assay, electrophoretic mobility-shift assay (EMSA), chromatin immunoprecipitation (ChIP), and western blot analysis. Overexpression of EGR2 promoted survival of KGN human granulosa-derived cells in which IER3 acts as a mediator; knockdown of EGR2 induced death in KGN cells. Additionally, EGR2 was found to regulate the expression of myeloid cell leukemia 1 (MCL-1), which belongs to the BCL-2 family of proteins regulating cell survival. Thus, this study identified a novel signaling axis, comprised of gonadotropins-EGR2-IER3, which is important for the survival of granulosa cells during folliculogenesis.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Proteína 2 de Resposta de Crescimento Precoce/genética , Gonadotropinas/metabolismo , Células da Granulosa/metabolismo , Proteínas de Membrana/genética , Ativação Transcricional , Animais , Sequência de Bases , Linhagem Celular , Sobrevivência Celular , Proteína 2 de Resposta de Crescimento Precoce/metabolismo , Feminino , Células da Granulosa/citologia , Humanos , Regiões Promotoras Genéticas , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley
17.
Infect Immun ; 83(11): 4266-76, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26283336

RESUMO

MdsABC is a Salmonella-specific tripartite efflux pump that has been implicated in the virulence of Salmonella enterica serovar Typhimurium; however, little is known about the virulence factors associated with this pump. We observed MdsABC expression-dependent alterations in the degree of resistance to extracellular oxidative stress and macrophage-mediated killing. Thin-layer chromatography and tandem mass spectrometry analyses revealed that overexpression of MdsABC led to increased secretion of 1-palmitoyl-2-stearoyl-phosphatidylserine (PSPS), affecting the ability of the bacteria to invade and survive in host cells. Overexpression of MdsABC and external addition of PSPS similarly rendered the mdsABC deletion strain resistant to diamide. Diagonal gel analysis showed that PSPS treatment reduced the diamide-mediated formation of disulfide bonds, particularly in the membrane fraction of the bacteria. Salmonella infection of macrophages induced the upregulation of MdsABC expression and led to an increase of intracellular bacterial number and host cell death, similar to the effects of MdsABC overexpression and PSPS pretreatment on the mdsABC deletion strain. Our study shows that MdsABC mediates a previously uncharacterized pathway that involves PSPS as a key factor for the survival and virulence of S. Typhimurium in phagocytic cells.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Infecções por Salmonella/microbiologia , Salmonella typhimurium/metabolismo , Salmonella typhimurium/patogenicidade , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica , Humanos , Macrófagos/metabolismo , Macrófagos/microbiologia , Proteínas de Membrana Transportadoras/genética , Salmonella typhimurium/genética , Virulência
18.
Biochem Biophys Res Commun ; 464(2): 392-5, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26067556

RESUMO

The delivery of biologically functional peptides into mammalian cells can be a direct and effective method for cancer therapy and treatment of other diseases. Discoidin domain receptor 2 (DDR2) is a collagen-induced receptor tyrosine kinase recently identified as a novel therapeutic target in lung cancer. In this study, we report that peptides containing the functional domain of DDR2 can be efficiently delivered into lung malignant cancer cells via a gold nanoparticle-DNA aptamer conjugate (AuNP-Apt)-based system. Peptide delivery resulted in the abrogation of DDR2 activation triggered by collagen. Moreover, the peptide delivered by the AuNP-Apt system inhibited cancer cell proliferation and invasion mediated by DDR2 activation. Thus, these results suggest that peptide loaded onto AuNP-Apt conjugates can be used for the development of peptide-based biomedical applications for the treatment of DDR2-positive cancer.


Assuntos
Aptâmeros de Nucleotídeos , Carcinoma Pulmonar de Células não Pequenas/patologia , Ouro/química , Neoplasias Pulmonares/patologia , Nanopartículas Metálicas , Peptídeos/administração & dosagem , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Receptores Mitogênicos/antagonistas & inibidores , Linhagem Celular Tumoral , Membrana Celular , Receptores com Domínio Discoidina , Humanos , Peptídeos/química , Receptores Proteína Tirosina Quinases/fisiologia , Receptores Mitogênicos/fisiologia
19.
Appl Environ Microbiol ; 81(15): 5266-77, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26025888

RESUMO

The bacterial 2-nitroreductase NbaA is the primary enzyme initiating the degradation of 2-nitrobenzoate (2-NBA), and its activity is controlled by posttranslational modifications. To date, the structure of NbaA remains to be elucidated. In this study, the crystal structure of a Cys194Ala NbaA mutant was determined to a 1.7-Å resolution. The substrate analog 2-NBA methyl ester was used to decipher the substrate binding site by inhibition of the wild-type NbaA protein. Tandem mass spectrometry showed that 2-NBA methyl ester produced a 2-NBA ester bond at the Tyr193 residue in the wild-type NbaA but not residues in the Tyr193Phe mutant. Moreover, covalent binding of the 2-NBA methyl ester to Tyr193 reduced the reactivity of the Cys194 residue on the peptide link. The Tyr193 hydroxyl group was shown to be essential for enzyme catalysis, as a Tyr193Phe mutant resulted in fast dissociation of flavin mononucleotide (FMN) from the protein with the reduced reactivity of Cys194. FMN binding to NbaA varied with solution NaCl concentration, which was related to the catalytic activity but not to cysteine reactivity. These observations suggest that the Cys194 reactivity is negatively affected by a posttranslational modification of the adjacent Tyr193 residue, which interacts with FMN and the substrate in the NbaA catalytic site.


Assuntos
Nitrobenzoatos/química , Nitrobenzoatos/metabolismo , Nitrorredutases/química , Nitrorredutases/metabolismo , Pseudomonas fluorescens/enzimologia , Sítios de Ligação , Cristalografia por Raios X , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Mutação de Sentido Incorreto , Ligação Proteica , Conformação Proteica , Processamento de Proteína Pós-Traducional , Cloreto de Sódio/metabolismo , Espectrometria de Massas em Tandem
20.
J Proteome Res ; 14(6): 2446-56, 2015 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-25871347

RESUMO

Granulosa cell tumor (GCT) is a rare form of ovarian cancer classified as a sex cord-stromal tumor. The c.402C→G missense mutation in the FOXL2 gene that changes cysteine 134 to tryptophan (C134W) is found in more than 97% of adult-type GCTs, and the C134W FOXL2 mutant is hyperphosphorylated. We identified three differential phosphorylation sites, at serine 33 (S33), tyrosine 186 (Y186), and serine 238 (S238), of the C134W mutant by tandem mass spectrometry. Among these sites, antibodies were raised against the pS33 and pY186 epitopes using specific peptides, and they were tested by immunostaining tissue microarrays of archival adult-type GCT specimens, other tumors, and normal tissues. The pS33 antibody showed greater sensitivity and specificity for the detection of adult-type GCTs than that of the other phospho and nonphospho antibodies. The specificity of the pS33 antibody to the pS33 epitope was further confirmed by enriching the pS33 peptide by affinity chromatography using the immobilized antibody, followed by mass spectrometric and western blot analyses from whole cell lysates of the adult-type GCT cell line, KGN. pS33 FOXL2 immunostaining levels were significantly higher in adult-type GCTs than those in other tumors and tissues. The receiver operating characteristic curve analysis of pS33 FOXL2 showed high sensitivity (1.0) and specificity (0.76) to adult-type GCTs with a cutoff score of >30% positive cells, and the area under the curve was 0.96. This suggests the potential of pS33 FOXL2 to serve as a new biomarker for the diagnosis of adult-type GCT.


Assuntos
Biomarcadores/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Tumor de Células da Granulosa/metabolismo , Proteínas Nucleares/metabolismo , Adulto , Anticorpos/imunologia , Células Cultivadas , Cromatografia de Afinidade , Proteína Forkhead Box L2 , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Humanos , Masculino , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/imunologia , Fosforilação
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