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1.
J Microbiol Immunol Infect ; 57(2): 269-277, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38278671

RESUMO

BACKGROUND: A new sublineage of emm1 group A Streptococcus (GAS), M1UK, has emerged in Europe, North America, and Australia. Notably, a significant portion of emm1 isolates in Asia, particularly in Hong Kong and mainland China, acquired scarlet fever-associated prophages following the 2011 Hong Kong scarlet fever outbreak. However, the presence of the M1UK sublineage has not yet been detected in Asia. METHODS: This study included 181 GAS isolates (2011-2021). The emm type of these isolates were determined, and 21 emm1 isolates from blood or pleural fluid (2011-2021) and 10 emm1 isolates from throat swabs (2016-2018) underwent analysis. The presence of the scarlet fever-associated prophages and the specific single nucleotide polymorphisms of the M1UK clone were determined by polymerase chain reaction and the genome sequencing. RESULTS: The M1UK lineage strains from throat swab and blood samples were identified. One of the M1UK strain in Taiwan carried the scarlet fever-associated prophage and therefore acquired the ssa, speC, and spd1 toxin repertoire. Nonetheless, the increase of M1UK was not observed until 2021, and there was a reduction in the diversity of emm types in 2020-2021, possibly due to the COVID-19 pandemic restriction policies in Taiwan. CONCLUSIONS: Our results suggested that the M1UK lineage clone has introduced in Taiwan. In Taiwan, the COVID-19 restrictions were officially released in March 2023; therefore, it would be crucial to continuously monitor the M1UK expansion and its related diseases in the post COVID-19 era.


Assuntos
COVID-19 , Escarlatina , Infecções Estreptocócicas , Humanos , Escarlatina/epidemiologia , Taiwan/epidemiologia , Pandemias , Proteínas da Membrana Bacteriana Externa/genética , Streptococcus pyogenes/genética , COVID-19/epidemiologia , Reino Unido , Antígenos de Bactérias/genética , Infecções Estreptocócicas/epidemiologia
2.
Nurse Educ Today ; 129: 105914, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37481921

RESUMO

BACKGROUND: Health disparities exist among lesbian, gay, bisexual, and transgender (LGBT) populations worldwide. However, student nurses and nurse staff have limited knowledge and skills in providing culturally competent nursing care for LGBT patients in Taiwan. OBJECTIVES: This paper describes the development, implementation, and evaluation of an online training program for the cultural competence of student nurses and nurses in Taiwan. DESIGN: A one-group pre-/post-test study design. SETTINGS: The study was conducted in five nursing schools, 10 nursing associations, and 37 long-term care facilities. Two prominent online bulletin boards (PTT Nurse and Dcard Nurse) and one Taiwanese nursing group on Facebook were used to recruit participants. PARTICIPANTS: In total, 301 student nurses and nurses participated in the study and responded to pre- and post-test questionnaires. METHODS: An online training program for culturally competent nursing care was developed and implemented. The pre- and post-test questionnaires contained three sections: (1) demographics, (2) knowledge of LGBT health, and (3) the Sexual Orientation Counselor Competency Scale. Three open-ended questions were included in the post-test questionnaire to evaluate the online training program. RESULTS: The online training program significantly improved the participants' knowledge and cultural competence skills. However, their attitudes towards cultural competence did not change after the program was implemented. Regarding qualitative feedback of the online training program, feedback on the strengths and limitations of the program was summarized under three themes: program content, website design, and online modules. CONCLUSIONS: The results suggest the importance of an online training program which may contribute to reducing health disparities among the LGBT population.


Assuntos
Enfermeiras e Enfermeiros , Minorias Sexuais e de Gênero , Estudantes de Enfermagem , Pessoas Transgênero , Humanos , Feminino , Masculino , Competência Cultural/educação , Comportamento Sexual
3.
Life Sci Alliance ; 6(6)2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37001914

RESUMO

RopB is a quorum-sensing regulator that binds to the SpeB-inducing peptide (SIP) under acidic conditions. SIP is known to be degraded by the endopeptidase PepO, whose transcription is repressed by the CovR/CovS two-component regulatory system. Both SIP-bound RopB (RopB-SIP) and SIP-free RopB (apo-RopB) can bind to the speB promoter; however, only RopB-SIP activates speB transcription. In this study, we found that the SpeB expression was higher in the ropB mutant than in the SIP-inactivated (SIP*) mutant. Furthermore, the deletion of ropB in the SIP* mutant derepressed speB expression, suggesting that apo-RopB is a transcriptional repressor of speB Up-regulation of PepO in the covS mutant degraded SIP, resulting in the down-regulation of speB We demonstrate that deleting ropB in the covS mutant derepressed the speB expression, suggesting that the speB repression in this mutant was mediated not only by PepO-dependent SIP degradation but also by apo-RopB. These findings reveal a crosstalk between the CovR/CovS and RopB-SIP systems and redefine the role of RopB in regulating speB expression in group A Streptococcus.


Assuntos
Proteínas de Bactérias , Infecções Estreptocócicas , Humanos , Virulência , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Streptococcus pyogenes/metabolismo , Peptídeos
4.
Hu Li Za Zhi ; 70(1): 17-22, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36647306

RESUMO

Gender identity is a topic of growing interest in mental health research. People with non-conforming gender identity are prone to suffer from stigmatization and bullying, and often present with psychiatric issues. Transgender denotes the broad spectrum of individuals who identify differently from their assigned gender. Some transgender people meet the requirements of the "gender dysphoria" (GD) diagnosis in the DSM-5-TR (diagnostic and statistical manual of mental disorders, fifth edition, text revision). When these individuals seek or undergo a social transition from male to female or female to male, which in many, but not all, cases also involves a somatic transition by cross-sex hormone treatment and genital (gender affirming) surgery, they are categorized as "transsexual". There are two requirements for transgender identity recognition in Taiwan: two psychiatrists' certificates of GD and the surgical removal of external and internal genitalia. In the DSM-5-TR, GD, as a general descriptive term, refers to the distress that may accompany the incongruence between one's experienced or expressed gender and one's assigned gender. GD manifests itself differently in different age groups. Several developmental-stage-dependent hormonal treatment options are available for GD. Puberty may exacerbate dysphoria due to the development of unwanted secondary sexual characteristics, which may be suppressed using a gonadotropin-releasing hormone agonist. On the other hand, gender-affirming hormones (aka cross-sex hormonal therapy) allow individuals to actively masculinize or feminize their physical appearance to become more consistent with their gender identity. In addition to biological treatment, psychosocial intervention is another key point for transgender people. These individuals experience higher risks of violence victimization, suicide, and sexual violence than their cisgender peers. Several studies have also indicated the presence of an association between autism spectrum disorder and GD. Mental health professionals should address these issues in practice and seek further understanding from transgender people.


Assuntos
Transtorno do Espectro Autista , Pessoas Transgênero , Humanos , Masculino , Feminino , Pessoas Transgênero/psicologia , Identidade de Gênero , Ansiedade , Estresse Psicológico
5.
J Glob Antimicrob Resist ; 31: 63-71, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35964863

RESUMO

OBJECTIVES: Staphylococcus argenteus is generally more susceptible to antibiotic treatments than Staphylococcus aureus; however, the study showed that the daptomycin/vancomycin-resistant S. argenteus was isolated from a patient with repeated antibiotic treatments. In this study, the methicillin- and vancomycin-susceptible S. argenteus isolates were used to characterize the phenotypes of S. argenteus after vancomycin passages in vitro. METHODS: Eleven S. argenteus isolates were used for passaging under different concentrations of vancomycin. The minimal inhibitory concentration (MIC) of vancomycin was determined by the agar dilution assay, and the biofilm mass of the passaged variants was quantified by the crystal violet staining assay and observed under the confocal microscope. RESULTS: The MIC of vancomycin for eight of 11 S. argenteus isolates was increased from ≤2 µg/mL to ≤4-8 µg/mL after vancomycin passages. Two variants with the high-level vancomycin-intermediate (vancomycin MIC ≤8 µg/mL) phenotype were identified, and the parental strains of these variants did not have the heterogeneous vancomycin-intermediate population determined by the population profile analysis. Further, three S. argenteus isolates showed an increase in biofilm production and icaA transcription after the low-dose (2 µg/mL) vancomycin passages. CONCLUSIONS: S. argenteus is capable of acquiring a vancomycin-tolerant phenotype and/or converting to a strong biofilm producer after vancomycin passages, which could contribute to the decrease of their antibiotic susceptibility.


Assuntos
Meticilina , Vancomicina , Vancomicina/farmacologia , Meticilina/farmacologia , Antibacterianos/farmacologia , Fenótipo
6.
Front Microbiol ; 12: 685343, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149675

RESUMO

The acquisition of the phage-encoded superantigen ssa by scarlet fever-associated group A Streptococcus (Streptococcus pyogenes, GAS) is found in North Asia. Nonetheless, the impact of acquiring ssa by GAS in invasive infections is unclear. This study initially analyzed the prevalence of ssa+ GAS among isolates from sterile tissues and blood. Among 220 isolates in northern Taiwan, the prevalence of ssa+ isolates increased from 1.5% in 2008-2010 to 40% in 2017-2019. Spontaneous mutations in covR/covS, which result in the functional loss of capacity to phosphorylate CovR, are frequently recovered from GAS invasive infection cases. Consistent with this, Phostag western blot results indicated that among the invasive infection isolates studied, 10% of the ssa+ isolates lacked detectable phosphorylated CovR. Transcription of ssa is upregulated in the covS mutant. Furthermore, in emm1 and emm12 covS mutants, ssa deletion significantly reduced their capacity to grow in human whole blood. Finally, this study showed that the ssa gene could be transferred from emm12-type isolates to the emm1-type wild-type strain and covS mutants through phage infection and lysogenic conversion. As the prevalence of ssa+ isolates increased significantly, the role of streptococcal superantigen in GAS pathogenesis, particularly in invasive covR/covS mutants, should be further analyzed.

7.
mSphere ; 5(3)2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32434842

RESUMO

The control of the virulence response regulator and sensor (CovR-CovS) two-component regulatory system in group A Streptococcus (GAS) strains regulates more than 15% of gene expression and has critical roles in invasive GAS infection. The membrane-embedded CovS has kinase and phosphatase activities, and both are required for modulating the phosphorylation level of CovR. Regulator of Cov (RocA) is a positive regulator of covR and also been shown to be a pseudokinase that interacts with CovS to enhance the phosphorylation level of CovR; however, how RocA modulates the activity of CovS has not been determined conclusively. Although the phosphorylation level of CovR was decreased in the rocA mutant in the exponential phase, the present study shows that phosphorylated CovR in the rocA mutant increased to levels similar to those in the wild-type strain in the stationary phase of growth. In addition, acidic stress, which is generally present in the stationary phase, enhanced the phosphorylation level of CovR in the rocA mutant. The phosphorylation levels of CovR in the CovS phosphatase-inactivated mutant and its rocA mutant were similar under acidic stress and Mg2+ (the signal that inhibits CovS phosphatase activity) treatments, suggesting that the phosphatase activity, but not the kinase activity, of CovS is required for RocA to modulate CovR phosphorylation. The phosphorylation level of CovR is crucial for GAS strains to regulate virulence factor expression; therefore, the growth phase- and pH-dependent RocA activity would contribute significantly to GAS pathogenesis.IMPORTANCE The emergence of invasive group A streptococcal infections has been reported worldwide. Clinical isolates that have spontaneous mutations or a truncated allele of the rocA gene (e.g., emm3-type isolates) are considered to be more virulent than isolates with the intact rocA gene (e.g., emm1-type isolates). RocA is a positive regulator of covR and has been shown to enhance the phosphorylation level of intracellular CovR regulator through the functional CovS protein. CovS is the membrane-embedded sensor and modulates the phosphorylation level of CovR by its kinase and phosphatase activities. The present study shows that the enhancement of CovR phosphorylation is mediated via the repression of CovS's phosphatase activity by RocA. In addition, we found that RocA acts dominantly on modulating CovR phosphorylation under neutral pH conditions and in the exponential phase of growth. The phosphorylation level of CovR is crucial for group A Streptococcus species to regulate virulence factor expression and is highly related to bacterial invasiveness; therefore, growth phase- and pH-dependent RocA activity and the sequence polymorphisms of rocA gene would contribute significantly to bacterial phenotype variations and pathogenesis.


Assuntos
Proteínas de Bactérias/metabolismo , Histidina Quinase/metabolismo , Proteínas Repressoras/metabolismo , Streptococcus pyogenes/patogenicidade , Transativadores/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Humanos , Monoéster Fosfórico Hidrolases/metabolismo , Fosforilação/genética , Infecções Estreptocócicas/patologia , Streptococcus pyogenes/genética , Transativadores/genética
8.
J Bacteriol ; 201(4)2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30478086

RESUMO

CovR/CovS is a two-component regulatory system in group A Streptococcus and primarily acts as a transcriptional repressor. The D53 residue of CovR (CovRD53) is phosphorylated by the sensor kinase CovS, and the phosphorylated CovRD53 protein binds to the intergenic region of rgg-speB to inhibit speB transcription. Nonetheless, the transcription of rgg and speB is suppressed in covS mutants. The T65 residue of CovR is phosphorylated in a CovS-independent manner, and phosphorylation at the D53 and T65 residues of CovR is mutually exclusive. Therefore, how phosphorylation at the D53 and T65 residues of CovR contributes to the regulation of rgg and speB expression was elucidated. The transcription of rgg and speB was suppressed in the strain that cannot phosphorylate the D53 residue of CovR (CovRD53A mutant) but restored to levels similar to those of the wild-type strain in the CovRT65A mutant. Nonetheless, inactivation of the T65 residue phosphorylation in the CovRD53A mutant cannot derepress the rgg and speB transcription, indicating that phosphorylation at the T65 residue of CovR is not required for repressing rgg and speB transcription. Furthermore, trans complementation of the CovRD53A protein in the strain that expresses the phosphorylated CovRD53 resulted in the repression of rgg and speB transcription. Unlike the direct binding of the phosphorylated CovRD53 protein and its inhibition of speB transcription demonstrated previously, the present study showed that inactivation of phosphorylation at the D53 residue of CovR contributes dominantly in suppressing rgg and speB transcription.IMPORTANCE CovR/CovS is a two-component regulatory system in group A Streptococcus (GAS). The D53 residue of CovR is phosphorylated by CovS, and the phosphorylated CovRD53 binds to the rgg-speB intergenic region and acts as the transcriptional repressor. Nonetheless, the transcription of rgg and Rgg-controlled speB is upregulated in the covR mutant but inhibited in the covS mutant. The present study showed that nonphosphorylated CovRD53 protein inhibits rgg and speB transcription in the presence of the phosphorylated CovRD53in vivo, indicating that nonphosphorylated CovRD53 has a dominant role in suppressing rgg transcription. These results reveal the roles of nonphosphorylated CovRD53 in regulating rgg transcription, which could contribute significantly to invasive phenotypes of covS mutants.


Assuntos
Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/metabolismo , Exotoxinas/biossíntese , Regulação Bacteriana da Expressão Gênica , Processamento de Proteína Pós-Traducional , Proteínas Repressoras/metabolismo , Streptococcus pyogenes/metabolismo , Transativadores/biossíntese , Transcrição Gênica , Proteínas de Bactérias/genética , Exotoxinas/genética , Genótipo , Fosforilação , Streptococcus pyogenes/classificação , Streptococcus pyogenes/genética , Transativadores/genética
9.
10.
Hepatology ; 59(6): 2238-50, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24470239

RESUMO

UNLABELLED: It is unclear how proliferating cells elicit suppression on cell proliferation and how cancer cells evade this growth suppression. Using a loss-of-function screening of the human kinome and phosphatome to identify genes suppressing tumor initiation in human hepatocellular carcinoma (HCC), we identified 19 genes and characterized one of the top-scoring tumor suppressor candidates, protein tyrosine phosphatase receptor type F (PTPRF). We found that PTPRF was induced during cell proliferation by cell-cell contact. Ectopic expression of wild-type PTPRF, but not the phosphatase-inactive mutant, suppressed cell proliferation and colony formation in soft-agar assays. In contrast, PTPRF silencing led to cell hyperproliferation, enhanced tumor colony formation in soft agar, and increased xenograft tumor growth in nude mice. Mechanistically, PTPRF silencing showed aberrant ERK-dependent signaling including the phosphorylation/stabilization of v-myc avian myelocytomatosis viral oncogene homolog (MYC) through the direct activation of v-src avian sarcoma viral oncogene homolog (SRC) and suppression of PP2A. This PTPRF-mediated growth suppression during cell proliferation functioned independently of the Hippo-Yap pathway. Clinically, PTPRF was down-regulated in 42% HCC (37/89), 67% gastric cancer (27/40), and 100% colorectal cancer (40/40). PTPRF up-regulation was found in 24% HCC (21/89) and associated with better clinical outcomes. CONCLUSION: A novel PTPRF-mediated growth suppression pathway was identified by way of a functional genomics screening in human hepatoma cells. Induction of PTPRF by cell-cell contact during cell proliferation quenched the activated ERK-dependent proliferation signaling to prevent cell hyperproliferation and tumor initiation. PTPRF down-regulation in HCC facilitated tumor development. Our findings shed light on how cancer cells can evade growth suppression and open a new avenue for future development of anticancer therapies.


Assuntos
Carcinoma Hepatocelular/enzimologia , Genes Supressores de Tumor , Genômica/métodos , Neoplasias Hepáticas/enzimologia , Fosfotransferases/metabolismo , Proteínas Tirosina Fosfatases Classe 2 Semelhantes a Receptores/metabolismo , Animais , Regulação para Baixo/genética , Humanos , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Camundongos Nus , Neoplasias Experimentais , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Interferência de RNA
11.
Hepatology ; 53(2): 504-16, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21246584

RESUMO

UNLABELLED: Intrahepatic metastasis is the primary cause of the high recurrence and poor prognosis of human hepatocellular carcinoma (HCC). However, neither its molecular mechanisms nor markers for its prediction before hepatectomy have been identified. We recently revealed up-regulation of erythroblastic leukemia viral oncogene homolog 3 (ERBB3) in human HCC. Here we examined the clinical and biological significance of ERBB3 in HCC. Up-regulation of ERBB3 in HCC was strongly associated with male gender (P < 0.001), chronic hepatitis B (P = 0.002), microscopic vascular invasion (P = 0.034), early recurrence (P = 0.003), and worse prognosis (P = 0.004). Phosphorylated ERBB3 and its ligands [neuregulins (NRGs)] were detected in both HCC tissues and cells. Phosphorylation of ERBB3 could be induced by conditioned media of HCC cells and abolished by the pretreatment of conditioned media with anti-NRG antibodies or by the silencing of the endogenous NRG expression of the donor HCC cells. Human epidermal growth factor receptor 2 was required for ERBB3 phosphorylation. The downstream phosphoinositide 3-kinase/v-akt murine thymoma viral oncogene homolog pathways were primarily elicited by NRG1/ERBB3 signaling, whereas the mitogen-activated protein kinase/extracellular signal-regulated kinase pathways were elicited by both epidermal growth factor/epidermal growth factor receptor and NRG1/ERBB3 signaling. The activation and silencing of ERBB3-dependent signaling had potent effects on both the migration and invasion of HCC cells, but neither had significant effects on the proliferation of HCC cells, tumor formation, or tumor growth in vitro and in vivo. CONCLUSION: The constitutive activation of ERBB3-dependent signaling via the NRG1/ERBB3 autocrine loop plays a crucial role in the regulation of cell motility and invasion, which contribute to intrahepatic metastasis and early recurrence of HCC. ERBB3 is a marker for the prediction of intrahepatic metastasis and early recurrence. ERBB3-dependent signaling is a candidate target for the treatment of microscopic vascular invasion and for the prevention of HCC recurrence.


Assuntos
Comunicação Autócrina/fisiologia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Neuregulina-1/metabolismo , Receptor ErbB-3/metabolismo , Carcinoma Hepatocelular/mortalidade , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células , Feminino , Inativação Gênica/efeitos dos fármacos , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Recidiva Local de Neoplasia , Fosforilação/fisiologia , Prognóstico , RNA Interferente Pequeno/farmacologia , Estudos Retrospectivos , Transdução de Sinais/fisiologia
12.
Mol Carcinog ; 49(5): 476-87, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20232364

RESUMO

Frequent intrahepatic metastasis causes early tumor recurrence and dismaying prognosis of human hepatocellular carcinoma (HCC). We recently identified overexpression of stathmin1 (STMN1) in human HCC. This study was designed to elucidate the clinical and biological significance of overexpression of STMN1 in HCC. Expression of STMN1 was conducted by quantitative reverse transcription-polymerase chain reaction and immunoblotting assays on 58 pairs of HCC and para-tumor liver tissues from patients with HCC along with normal liver tissues as the controls. Association of STMN1 overexpression with tumor recurrence and prognosis was investigated by Kaplan-Meier cumulative survival and Cox Regression analyses. Roles of STMN1 in cell cycle, cell motility, and invasion were determined by in vitro assays. STMN1 overexpression in hepatoma was strongly associated with local invasion (P = 0.031), early recurrence (P = 0.002), and poor prognosis (P = 0.005), and was an independent indicator for tumor recurrence (P = 0.0045). STMN1 overexpression further identified subgroups of HCC patients with higher tumor recurrence and worse prognosis among HCC patients with early tumor stage (T1) or intermediate histological grades (G2 and G3), both of whom represent the majority of HCC patients receiving primary curative hepatectomy. Silencing STMN1 expression via RNA interference suppressed invasion activity, while ectopic expression of STMN1 enhanced cell invasion and caused polyploidy of cells. In conclusion, STMN1 overexpression could predict early tumor recurrence and poor prognosis, particularly at early stage of hepatoma. Overexpression of STMN1 promoted polyploidy formation, tumor-cell invasion, and intrahepatic metastasis, suggesting that STMN1 can be a target for anti-cancer therapy of human hepatoma.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Estatmina/genética , Carcinoma Hepatocelular/genética , Feminino , Inativação Gênica , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Risco
13.
J Proteome Res ; 8(8): 3977-86, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19545154

RESUMO

Evading apoptosis is pivotal in both of carcinogenesis and resistance to anticancer therapy. We investigated the molecules and pathways of apoptosis evasion in human hepatoma cells by irradiating hepatoma cells with optimized UV (so-called "hormetic responses"). Proteins and pathways related to hormetic responses were identified via proteomic approaches followed by reconstruction of function-networks. Of the 2326 defined protein spots, 42 distinct proteins significantly changed their expression. Eleven hormetic response proteins (HINT1, PHB, CTSD, ANXA1, LGASL1, TPT1, NPM, PRDX2, UCHL1, CERK, and C1QBP) were involved in 5 death-regulatory pathways, including the p53-dependent apoptotic pathway, protein ubiquinization, cellular redox, calcium-mediated signaling pathway, and sphingomyelin-metabolism pathway. Knockdown of HINT1 expression via RNA interference increased tumor cell resistance to apoptosis induction, while silencing NPM, UCHL1, or CERK greatly sensitized tumor cells to apoptosis induction. In conclusion, NPM, UCHL1, and CERK act as apoptosis-evasion proteins that may serve as therapeutic targets for hepatoma. Silencing their expression would increase therapeutic efficacy, thereby reducing the corresponding doses and side-effects of anticancer therapy. This model of induction of cellular hormetic responses to identify apoptosis-evasion molecules/pathways via proteomic approaches can be applied to other modalities of anticancer therapy.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/efeitos da radiação , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , Proteômica/métodos , Sequência de Aminoácidos , Análise de Variância , Apoptose/fisiologia , Proteínas Reguladoras de Apoptose/efeitos da radiação , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/radioterapia , Linhagem Celular Tumoral , Eletroforese em Gel Bidimensional , Humanos , Immunoblotting , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/radioterapia , Dados de Sequência Molecular , Proteínas de Neoplasias/efeitos da radiação , Proibitinas , Proteoma/metabolismo , Proteoma/efeitos da radiação , Interferência de RNA , Reprodutibilidade dos Testes , Transdução de Sinais/efeitos da radiação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Proteína Tumoral 1 Controlada por Tradução , Raios Ultravioleta
14.
Dev Growth Differ ; 24(4): 319-325, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-37281332

RESUMO

Ovaries of hypophysectomized Rana catesbeiana tadpoles. weighing I to 14 g, were prepared for electron microscopic study. The oocytes are at the growth phase, ranging from 50 to 190 µm in diameter. The observation on these oocytes has revealed the presence of intramitochondrial yolk-crystals but not cytoplasmic yolk platelets. The crystalline structure, situated within the intracristal space, consists of a hexagonal array of dense particles about 50 Å in diameter and 72 Å in periodicity. Our data agree with those reported in oocytes of intact ranid species. According to literatures, crystals of intramitochondrial yolk and of cytoplasmic yolk platelets show similar ultrasturctures. The precursor of cytoplasmic yolk platelets in adult Xenopus oocytes is known to be synthesized in the estrogen-stimulated liver and incorporated via circulation into oocytes by gonadotropin-dependent micropinocytosis. The present finding suggests that the intramitochondrial yolk could be formed within oocytes, independently of the pituitary control.

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