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1.
BMC Ophthalmol ; 23(1): 145, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37029360

RESUMO

BACKGROUND: Severe ocular surface disorders are one of the major blinding diseases, and a paucity of original tissue obscures successful reconstruction. We developed a new surgical technique of direct oral mucosal epithelial transplantation (OMET) to reconstruct severely damaged ocular surfaces in 2011. This study elaborates on the clinical efficacy of OMET. METHODS: A retrospective review of patients with severe ocular surface disorders who underwent OMET from 2011 to 2021 at the Department of Ophthalmology, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine was conducted. Patients who were followed up for at least 3 months postoperatively and had sufficient pre or postoperative records were included. Surgical efficacy was evaluated by comparing the best-corrected visual acuity (BCVA), corneal transparency, neovascularization grade, and symblepharon grade. Additionally, postoperative ocular surface impression cytology was used to study the morphology of the newborn epithelial cells. RESULTS: Forty-eight patients (49 eyes; mean age: 42.55 ± 12.40 years, range:12-66 years) were enrolled in the study. The etiology included chemical burns (30 eyes), thermal burns (16 eyes), explosive injuries (1 eye), Stevens-Johnson syndrome (1 eye), and multiple pterygiums (1 eye). The mean follow-up period was 25.97 ± 22.99 months. Postoperatively, 29 eyes (59.18%) showed improved corneal transparency, 26 eyes (53.06%) had improved BCVA, 47 eyes (95.92%) had a stable epithelium until the final follow-up, 44 eyes (89.80%) had a reduced neovascularization grade. Of the 20 eyes with preoperative symblepharon, 15 (75%) were completely resolved, and five (25%) were partially resolved. Impression cytological studies showed no postoperative conjunctival invasion onto the corneal surface. CONCLUSIONS: OMET is a safe and effective surgical technique for reconstruction in severe ocular surface disorder by maintaining a stable epithelium and reducing the neovascularization and symblepharon grade.


Assuntos
Queimaduras Químicas , Doenças da Córnea , Epitélio Corneano , Queimaduras Oculares , Limbo da Córnea , Pterígio , Recém-Nascido , Humanos , Adulto , Pessoa de Meia-Idade , Doenças da Córnea/cirurgia , Resultado do Tratamento , Mucosa Bucal , Córnea , Estudos Retrospectivos , Queimaduras Oculares/cirurgia
2.
PLoS Pathog ; 19(2): e1011189, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36812247

RESUMO

Increasing evidence highlights the role of bacteria in promoting tumorigenesis. The underlying mechanisms may be diverse and remain poorly understood. Here, we report that Salmonella infection leads to extensive de/acetylation changes in host cell proteins. The acetylation of mammalian cell division cycle 42 (CDC42), a member of the Rho family of GTPases involved in many crucial signaling pathways in cancer cells, is drastically reduced after bacterial infection. CDC42 is deacetylated by SIRT2 and acetylated by p300/CBP. Non-acetylated CDC42 at lysine 153 shows an impaired binding of its downstream effector PAK4 and an attenuated phosphorylation of p38 and JNK, consequently reduces cell apoptosis. The reduction in K153 acetylation also enhances the migration and invasion ability of colon cancer cells. The low level of K153 acetylation in patients with colorectal cancer (CRC) predicts a poor prognosis. Taken together, our findings suggest a new mechanism of bacterial infection-induced promotion of colorectal tumorigenesis by modulation of the CDC42-PAK axis through manipulation of CDC42 acetylation.


Assuntos
Neoplasias Colorretais , Infecções por Salmonella , Proteína cdc42 de Ligação ao GTP , Humanos , Acetilação , Carcinogênese , Proteína cdc42 de Ligação ao GTP/metabolismo , Transformação Celular Neoplásica , Quinases Ativadas por p21/metabolismo , Transdução de Sinais
3.
Virology ; 556: 140-148, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33631413

RESUMO

Herpes simplex virus 1 causes recurrent diseases by reactivating from latency, which requires the viral thymidine kinase (TK) gene. An acyclovir-resistant mutation in TK, V204G, was previously repeatedly identified in a patient with recurrent herpetic keratitis. We found that compared with its parental strain KOS, a laboratory-derived V204G mutant virus was impaired in replication in cultured neurons despite little defect in non-neuronal cells. After corneal inoculation of mice, V204G exhibited defects in ocular replication that were modest over the first three days but severe afterward. Acute replication of V204G in trigeminal ganglia was significantly impaired. However, V204G established latency with viral loads as high as KOS and reactivated with high frequency albeit reduced kinetics. Acyclovir treatment that drastically decreased ocular and ganglionic replication of KOS had little effect on V204G. Thus, despite reduced neuronal replication due to impaired TK activity, this clinically relevant drug-resistant mutant can efficiently establish reactivatable latency.


Assuntos
Herpesvirus Humano 1 , Ceratite Herpética/virologia , Neurônios/virologia , Animais , Linhagem Celular Tumoral , Chlorocebus aethiops , Células Epiteliais , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/patogenicidade , Humanos , Camundongos , Células Vero , Ativação Viral , Replicação Viral
4.
J Zhejiang Univ Sci B ; 19(3): 218-226, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29504315

RESUMO

OBJECTIVE: To assess the lower tear meniscus height (LTMH), central tear film thickness (CTFT), and central corneal epithelial thickness (CCET) after deep anterior lamellar keratoplasty (DALK). METHODS: This was a retrospective cross-sectional study of 20 patients who had DALK in one eye over a three-month period. LTMH, CTFT, and CCET of the operated eyes and the unoperated fellow eyes were measured using high-definition optical coherence tomography (HD-OCT). Correlations between three OCT assessments and age, time following surgery, graft size, bed size, and the number of residual sutures were analyzed. RESULTS: Compared to patients with keratoconus, patients with other corneal conditions had significantly higher CCET in the fellow eye (P=0.024). For all patients, CCET in the operated eye was significantly negatively correlated with the number of residual sutures (R=-0.579, P=0.008), and was significantly positively correlated with time following surgery (R=0.636, P=0.003). In the fellow eye, a significant positive correlation was found between age and CCET (R=0.551, P=0.012), and a significant negative correlation between age and CTFT (R=-0.491, P=0.028). LTMH was found to be significantly correlated between operated and fellow eyes (R=0.554, P=0.011). There was no significant correlation between LTMH and age, bed/graft size, time following surgery, or residual sutures (all possible correlations, P>0.05). CONCLUSIONS: Patients with keratoconus tend to have a thinner central corneal epithelium. Corneal epithelium keeps regenerating over time after DALK. DALK did not induce a significant change in tear volume compared with the fellow eye. Postoperative tear function might depend on an individual's general condition, rather than on age, gender, bed/graft size, time following surgery, or residual sutures.


Assuntos
Transplante de Córnea , Epitélio Corneano/patologia , Lágrimas , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia de Coerência Óptica
5.
Optom Vis Sci ; 95(1): 76-81, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29252907

RESUMO

SIGNIFICANCE: As patients with previous radial keratotomy (RK) are still occasionally encountered, recognition of the anatomy of post-RK corneas and management of their complications remain relevant. High-definition anterior segment optical coherence tomography (AS-OCT) is a very useful tool to assess these postsurgical corneas. PURPOSE: To describe a case of acute corneal hydrops with Descemet membrane schisis after RK with observation by AS-OCT. CASE REPORT: A 43-year-old woman presented with a 9-day history of sudden vision loss, foreign body sensation, and photophobia in her left eye. She had undergone bilateral RK 25 years ago at her local hospital. Slit-lamp examination revealed marked corneal edema and stromal clefts in the central cornea along with radial surgical scars in her left eye. Pentacam imaging showed the typical pattern of a post-RK cornea with ectasia in her right eye. Multiple dilacerations of collagen lamellae and fluid-filled intrastromal cysts together with epithelial edema were observed in her left eye using AS-OCT. A Descemet membrane detachment with schisis was also shown by AS-OCT. After 5 months of medication with topical 0.1% fluorometholone eye drops four times daily together with 3% ofloxacin eye ointment once daily, the corneal edema, Descemet membrane detachment, and Descemet membrane schisis had completely resolved resulting in pan-stromal scarring. CONCLUSIONS: This report describes acute corneal hydrops with Descemet membrane schisis after RK imaged using high-definition AS-OCT. The acute hydrops was possibly caused by corneal ectasia or underlying keratoconus, which was aggravated by RK. High-definition AS-OCT is a useful tool to demonstrate the details of different corneal layers and to observe the resolving process of acute hydrops. Topical medications consisting of antibiotic, lubrication, and corticosteroid can be used to treat the acute event effectively.


Assuntos
Doenças da Córnea/etiologia , Edema da Córnea/etiologia , Lâmina Limitante Posterior/patologia , Ceratocone/etiologia , Ceratotomia Radial/efeitos adversos , Adulto , Cicatriz/cirurgia , Doenças da Córnea/diagnóstico por imagem , Edema da Córnea/diagnóstico por imagem , Lâmina Limitante Posterior/diagnóstico por imagem , Dilatação Patológica/diagnóstico por imagem , Dilatação Patológica/etiologia , Feminino , Humanos , Ceratocone/diagnóstico por imagem , Masculino , Complicações Pós-Operatórias , Tomografia de Coerência Óptica
6.
Future Microbiol ; 12: 1045-1057, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28796533

RESUMO

AIM: Acid is an important environmental condition encountered frequently by Salmonella enterica serovar Typhimurium during its pathogenesis, but the role of small-noncoding RNAs (sRNAs) in response to acid stress is poorly understood. METHODS: We used RNA sequencing to explore acid-responsive sRNAs in S. Typhimurium. RESULTS: It identified that 6S RNA encoded by the ssrS was significantly upregulated at pH 3.0. The 6S RNA knockout strain showed a reduced ability to survive at pH 3.0. Additionally, genes in Salmonella pathogenicity island-1 were downregulated in the 6S RNA knockout strain. The loss of 6S RNA significantly reduced S. Typhimurium invasion ability in HeLa cells and virulence in a mouse model. CONCLUSION: These findings demonstrate that 6S RNA plays an important role in S. Typhimurium survival under extremely acid conditions and for invasion of epithelial cells.


Assuntos
Células Epiteliais/microbiologia , RNA Bacteriano/genética , RNA Bacteriano/fisiologia , RNA não Traduzido/genética , RNA não Traduzido/fisiologia , Salmonella typhimurium/genética , Sorogrupo , Virulência/genética , Animais , Modelos Animais de Doenças , Células Epiteliais/patologia , Regulação Bacteriana da Expressão Gênica , Técnicas de Inativação de Genes , Genes Bacterianos/genética , Ilhas Genômicas/genética , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Camundongos Endogâmicos BALB C , RNA Bacteriano/isolamento & purificação , Pequeno RNA não Traduzido/genética , Pequeno RNA não Traduzido/fisiologia , Salmonella typhimurium/patogenicidade , Análise de Sequência de RNA/métodos , Estresse Fisiológico/genética
7.
J Zhejiang Univ Sci B ; 18(6): 539-543, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28585430

RESUMO

OBJECTIVE: To report surgical management and favorable outcome in a case with delayed repair of traumatic laser in situ keratomileusis (LASIK) flap dislocation with shrinkage and folds. METHODS: A 30-year-old man with a five-year history of bilateral LASIK experienced blunt trauma to his right eye followed by decreased vision for 5 weeks. The surgical management included initially softening the flap by irrigation with balanced salt solution (BSS). The shrinkage folds were carefully and gently stretched by scraping with a 26-gauge cannula accompanied by BSS irrigation. All of the epithelial ingrowth on the flap inner surface and on the bed was thoroughly debrided by scraping and irrigation. After the flap was repositioned to match its original margin, a soft bandage contact lens was placed. RESULTS: At his initial visit, slit-lamp microscopy and optical coherence tomography (OCT) showed shrinkage of the LASIK flap with an elevated margin approximately 3 mm above the original position. The flap covered half of the pupil and had multiple horizontal folds. Two months after surgery, the flap remained well positioned with only faint streaks in the anterior stroma. The uncorrected visual acuity of the right eye was 20/20 with a manifest refraction of Plano. CONCLUSIONS: For delayed repair of traumatically dislocated LASIK flaps, sufficient softening by BSS, stretching the shrinkage folds, and thorough debridement of ingrowth epithelium enable resetting the flap and provide satisfactory results.


Assuntos
Traumatismos Oculares/cirurgia , Ceratomileuse Assistida por Excimer Laser In Situ , Retalhos Cirúrgicos , Ferimentos não Penetrantes/cirurgia , Adulto , Desbridamento , Traumatismos Oculares/patologia , Traumatismos Oculares/fisiopatologia , Humanos , Masculino , Irrigação Terapêutica , Resultado do Tratamento , Acuidade Visual , Ferimentos não Penetrantes/patologia , Ferimentos não Penetrantes/fisiopatologia
8.
Tumour Biol ; 39(2): 1010428317691182, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28231725

RESUMO

Extracellular vesicles have emerged as important mediators of intercellular communication and play an active role in cancer, including breast cancer. Despite limited studies, initial observations suggest that these vesicles are important in breast physiology and pathophysiology. We here, in brief, describe their potential use as future biomarkers and therapeutic agents in breast cancer. Extracellular vesicles in blood and breast fluid may have a great potential to detect and predict the presence of breast cancer, and extracellular vesicles modulation may emerge as a therapeutic approach in cancer therapy.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Linhagem Celular Tumoral , Feminino , Terapia Genética/métodos , Humanos , Células MCF-7
9.
BMC Ophthalmol ; 16(1): 158, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27590038

RESUMO

BACKGROUND: Reis-Bücklers corneal dystrophy (RBCD) was consistently reported as a corneal dystrophy only affected Bowman's layer and superficial corneal stroma, and superficial keratectomy was a recommendation surgery for treatment in literatures. The study reported new histopathological and ultrastructural findings in RBCD caused by the Arg124Leu mutation of transforming growth factor induced (TGFBI) gene in a four-generation Chinese pedigree. METHODS: Subjects including eight patients and seven unaffected family members received slit-lamp biomicroscopy and photography. DNA was obtained from all subjects, and exons 4 and 11 to 14 of TGFBI gene were analyzed by polymerase chain reaction and the products were sequenced. Anterior segment optical coherence tomography (AS OCT) and in vivo confocal microscopy were conducted for ten eyes of five patients. Based on the results of AS OCT and in vivo confocal microscopy, deep anterior lamellar keratoplasty (DLKP) using cryopreserved donor cornea was applied for four eyes of four patients. Four lamellar dystrophic corneal buttons were studied by light and transmission electron microscopy, and TGFBI immunohistochemistry. RESULTS: Eight patients had typical clinical manifestations of RBCD presenting recurrent painful corneal erosion starting in their early first decades, along with age-dependent progressive geographic corneal opacities. TGFBI sequencing revealed a heterozygous mutation, Arg124Leu in all eight patients. Anterior segment optical coherence tomography and in vivo confocal microscopy showed the dystrophic deposits involved not only in subepithelial and superficial stroma, but also in mid- or posterior stroma in four examined advanced eyes. Light microscopy showed Bowman's layer was absent, replaced by abnormal deposits stain bright red with Masson's trichrome. In superficial cornea, the deposits stacked and produced three to five continuous bands parallel to the corneal collagen lamellae. In mid- to posterior stroma, numerous granular or dot- like aggregates were heavily scattered, and most of them presented around the nuclei of stromal keratocytes. Transmission electron microscopy revealed the multiple electron-dense rod-shaped deposits aggregated and formed a characteristic pattern of three to five continuous bands in superficial cornea, which were similar to those seen under light microscopy. In mid- to posterior stroma, clusters of rod-shaped bodies were scattered extracellular or intracellular of the stromal keratocytes between the stromal lamellae suggesting the close relationship between mutated proteins and keratocyte. CONCLUSIONS: The study offer evidences indicating DLKP is a viable treatment option for advanced RBCD to avoid recurrence, and the mutated TGFBIp in dystrophic corneas are of keratocytes origin.


Assuntos
Distrofias Hereditárias da Córnea/genética , Distrofias Hereditárias da Córnea/patologia , Fator de Crescimento Transformador beta/genética , Adolescente , Adulto , Idoso , Povo Asiático , Lâmina Limitante Anterior/patologia , Lâmina Limitante Anterior/ultraestrutura , Criança , Pré-Escolar , Córnea/patologia , Córnea/ultraestrutura , Distrofias Hereditárias da Córnea/cirurgia , Ceratócitos da Córnea/patologia , Substância Própria/patologia , Substância Própria/ultraestrutura , Éxons , Proteínas da Matriz Extracelular/genética , Feminino , Humanos , Imuno-Histoquímica , Ceratoplastia Penetrante , Masculino , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade , Mutação , Linhagem , Reação em Cadeia da Polimerase , Tomografia de Coerência Óptica , Adulto Jovem
10.
Sci Rep ; 6: 30837, 2016 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-27484197

RESUMO

The regulation of chromosomal replication is critical and the activation of DnaA by ATP binding is a key step in replication initiation. However, it remains unclear whether and how the process of ATP-binding to DnaA is regulated. Here, we show that DnaA can be acetylated, and its acetylation level varies with cell growth and correlates with DNA replication initiation frequencies in E. coli. Specifically, the conserved K178 in Walker A motif of DnaA can be acetylated and its acetylation level reaches the summit at the stationary phase, which prevents DnaA from binding to ATP or oriC and leads to inhibition of DNA replication initiation. The deacetylation process of DnaA is catalyzed by deacetylase CobB. The acetylation process of DnaA is mediated by acetyltransferase YfiQ, and nonenzymatically by acetyl-phosphate. These findings suggest that the reversible acetylation of DnaA ensures cells to respond promptly to environmental changes. Since Walker A motif is universally distributed across organisms, acetylation of Walker A motif may present a novel regulatory mechanism conserved from bacteria to eukaryotes.


Assuntos
Proteínas de Bactérias/metabolismo , Replicação do DNA , Proteínas de Ligação a DNA/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/genética , Lisina/química , Organofosfatos/metabolismo , Fosfotransferases/metabolismo , Origem de Replicação , Acetilação , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Proteínas de Ligação a DNA/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Lisina/metabolismo , Fosfotransferases/genética
12.
Gene ; 588(2): 115-23, 2016 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-27173635

RESUMO

As a global transcriptional regulator, H-NS, the histone-like nucleoid-associated DNA-binding and bridging protein, plays a wide range of biological roles in bacteria. In order to determine the role of H-NS in regulating gene transcription and further find out the biological significance of this protein in Enterohemorrhagic Escherichia coli (EHEC), we conducted transcriptome analysis of hns mutant by RNA sequencing. A total of 983 genes were identified to be regulated by H-NS in EHEC. 213 and 770 genes were down-regulated and up-regulated in the deletion mutant of hns, respectively. Interestingly, 34 of 97 genes on virulence plasmid pO157 were down-regulated by H-NS. Although the deletion mutant of hns showed a decreased survival rate in macrophage compared with the wild type strain, it exhibited the higher ability to colonize mice gut and became more virulent to BALB/c mice. The BALB/c mice infected with the deletion mutant of hns showed a lower survival rate, and a higher bacterial burden in the gut, compared with those infected with wild type strain, especially when the gut microbiota was not disturbed by antibiotic administration. These findings suggest that H-NS plays an important role in virulence of EHEC by interacting with host gut microbiota.


Assuntos
Antibiose , Escherichia coli Êntero-Hemorrágica/patogenicidade , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Proteínas de Fímbrias/genética , Regulação Bacteriana da Expressão Gênica , Transcriptoma , Animais , Carga Bacteriana , Sequência de Bases , Modelos Animais de Doenças , Escherichia coli Êntero-Hemorrágica/genética , Escherichia coli Êntero-Hemorrágica/crescimento & desenvolvimento , Infecções por Escherichia coli/mortalidade , Infecções por Escherichia coli/patologia , Feminino , Proteínas de Fímbrias/deficiência , Microbioma Gastrointestinal/fisiologia , Perfilação da Expressão Gênica , Interações Hospedeiro-Patógeno , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Plasmídeos/química , Plasmídeos/metabolismo , Deleção de Sequência , Análise de Sobrevida , Virulência
13.
Mol Med Rep ; 14(1): 3-15, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27176595

RESUMO

Pterygium is a common ophthalmic disease affecting humans only. Extensive epidemiological data have demonstrated a causative effect of chronic ultraviolet (UV) radiation on pterygia. Progress has been made in determining the origin of pterygia, their nasal predilection and wing­shaped appearance, and the roles of UV radiation in the initiation and the development of pterygia. In the present review, the current understanding of the involvement of UV radiation in the pathogenesis of pterygia is summarized. This involvement includes the alteration of limbal stem cells and fibroblasts that contribute to the initiation of pterygia and the induction of various pro­inflammatory cytokines, growth factors and matrix metalloproteinases that promote the progression of pterygia. Further elucidation of the roles of UV radiation in the pathogenesis of pterygia may help to encourage individuals at risk of developing pterygia to take preventive measures and aid researchers in the development of novel targeted therapeutic agents to treat pterygia.


Assuntos
Pterígio/etiologia , Raios Ultravioleta/efeitos adversos , Animais , Lâmina Limitante Anterior/metabolismo , Lâmina Limitante Anterior/patologia , Citocinas/genética , Citocinas/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Neovascularização Patológica/etiologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Pterígio/patologia , Células Estromais/metabolismo , Células Estromais/efeitos da radiação , Inibidores Teciduais de Metaloproteinases/genética , Inibidores Teciduais de Metaloproteinases/metabolismo
14.
PLoS Pathog ; 12(3): e1005458, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26943369

RESUMO

The two-component system PhoP-PhoQ is highly conserved in bacteria and regulates virulence in response to various signals for bacteria within the mammalian host. Here, we demonstrate that PhoP could be acetylated by Pat and deacetylated by deacetylase CobB enzymatically in vitro and in vivo in Salmonella Typhimurium. Specifically, the conserved lysine residue 201(K201) in winged helix-turn-helix motif at C-terminal DNA-binding domain of PhoP could be acetylated, and its acetylation level decreases dramatically when bacteria encounter low magnesium, acid stress or phagocytosis of macrophages. PhoP has a decreased acetylation and increased DNA-binding ability in the deletion mutant of pat. However, acetylation of K201 does not counteract PhoP phosphorylation, which is essential for PhoP activity. In addition, acetylation of K201 (mimicked by glutamine substitute) in S. Typhimurium causes significantly attenuated intestinal inflammation as well as systemic infection in mouse model, suggesting that deacetylation of PhoP K201 is essential for Salmonella pathogenesis. Therefore, we propose that the reversible acetylation of PhoP K201 may ensure Salmonella promptly respond to different stresses in host cells. These findings suggest that reversible lysine acetylation in the DNA-binding domain, as a novel regulatory mechanism of gene expression, is involved in bacterial virulence across microorganisms.


Assuntos
Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Infecções por Salmonella/imunologia , Salmonella typhimurium/patogenicidade , Acetilação , Sequência de Aminoácidos , Animais , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA , Modelos Animais de Doenças , Humanos , Lisina/química , Macrófagos/metabolismo , Camundongos , Dados de Sequência Molecular , Fagocitose , Fosforilação , Estrutura Terciária de Proteína , Infecções por Salmonella/microbiologia , Salmonella typhimurium/genética , Salmonella typhimurium/imunologia , Alinhamento de Sequência , Deleção de Sequência , Virulência
15.
J Infect Dis ; 213(11): 1836-45, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-26810370

RESUMO

Salmonella causes a range of diseases in different hosts, including enterocolitis and systemic infection. Lysine acetylation regulates many eukaryotic cellular processes, but its function in bacteria is largely unexplored. The acetyltransferase Pat and NAD(+)-dependent deacetylase CobB are involved in the reversible protein acetylation in Salmonella Typhimurium. Here, we used cell and animal models to evaluate the virulence of pat and cobB deletion mutants in S. Typhimurium and found that pat is critical for bacterial intestinal colonization and systemic infection. Next, to understand the underlying mechanism, genome-wide transcriptome was analyzed. RNA sequencing data showed that the expression of Salmonella pathogenicity island 1 (SPI-1) is partially dependent on pat In addition, we found that HilD, a key transcriptional regulator of SPI-1, is a substrate of Pat. The acetylation of HilD by Pat maintained HilD stability and was essential for the transcriptional activation of HilA. Taken together, these results suggest that a protein acetylation system regulates SPI-1 expression by controlling HilD in a posttranslational manner to mediate S. Typhimurium virulence.


Assuntos
Proteínas de Bactérias/metabolismo , Salmonella typhimurium/patogenicidade , Acetilação , Acetiltransferases/metabolismo , Animais , Hidrolases de Éster Carboxílico/metabolismo , Citocinas/metabolismo , Ativação Enzimática , Deleção de Genes , Células HeLa , Humanos , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Mutação , Células RAW 264.7 , Salmonella typhimurium/enzimologia , Salmonella typhimurium/genética , Salmonella typhimurium/metabolismo , Transcriptoma , Virulência
16.
Curr Opin Oncol ; 27(6): 457-65, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26371779

RESUMO

PURPOSE OF REVIEW: Anthracyclines and taxanes are the two most active classes of cytotoxic agents that are commonly used for the treatment of breast cancer. However, resistance to these agents has become a major clinical obstacle. The aim of the present review is to define the roles of noncoding RNA (ncRNA) in breast cancer progression and the development of chemotherapy resistance. The ultimate goal is to exploit ncRNAs as new therapeutic tools to overcome resistance. RECENT FINDINGS: Two important types of ncRNA include microRNA (miRNA) and long noncoding RNA (lncRNA). Both miRNA and lncRNA have recently impacted the field of breast cancer research as important pieces in the mechanistic puzzle of the genes and pathways involved in breast cancer development and progression. SUMMARY: Herein, we review the roles of miRNA and lncRNA in breast cancer progression and the development of chemotherapy resistance. Future research should include identification of ncRNAs that could be potential therapeutic targets in chemotherapy-resistant tumors, as well as ncRNA biomarkers that facilitate more tumor-specific treatment options for chemotherapy-resistant breast cancer patients.


Assuntos
Antraciclinas/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Resistencia a Medicamentos Antineoplásicos/genética , RNA não Traduzido/fisiologia , Taxoides/uso terapêutico , Antibióticos Antineoplásicos/uso terapêutico , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/fisiologia
17.
Cell Physiol Biochem ; 36(6): 2274-86, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26279432

RESUMO

BACKGROUND: Currently, exosomes that act as mediators of intercellular communication are being researched extensively. Our previous studies confirmed that these exosomes contain microRNAs (miRNAs) that could alter chemo-susceptibility, which is partly attributed to the successful intercellular transfer of multidrug resistance (MDR)-specific miRNAs. We also confirmed that ß-elemene could influence MDR-related miRNA expression and regulate the expression of the target genes PTEN and Pgp, which may lead to the reversal of the chemoresistant breast cancer (BCA) cells. We are the first to report these findings, and we propose the following logical hypothesis: ß-elemene can mediate MDR-related miRNA expression in cells, thereby affecting the exosome contents, reducing chemoresistance transmission via exosomes, and reversing the drug resistance of breast cancer cells. METHODS: MTT-cytotoxic, miRNA microarray, real-time quantitative PCR, Dual Luciferase Activity Assay, and Western blot analysis were performed to investigate the impact of ß-elemene on the expression of chemoresistance specific miRNA and PTEN as well as Pgp in chemoresistant BCA exosomes. RESULTS: Drug resistance can be reversed by ß-elemene related to exosomes. There were 104 differentially expressed miRNAs in the exosomes of two chemoresistant BCA cells: adriacin (Adr) - resistant MCF-7 cells (MCF-7/Adr) and docetaxel (Doc) - resistant MCF-7 cells (MCF-7/Doc) that underwent treatment. Of these, 31 miRNAs were correlated with the constant changes in the MDR. The expression of miR-34a and miR-452 can lead to changes in the characteristics of two chemoresistant BCA exosomes: MCF-7/Adr exosomes (A/exo) and MCF-7/Doc exosomes (D/exo). The PTEN expression affected by ß-elemene was significantly increased, and the Pgp expression affected by ß-elemene was significantly decreased in both cells and exosomes. ß-elemene induced a significant increase in the apoptosis rate in both MCF-7/Doc and MCF-7/Adr cells. CONCLUSIONS: Drug resistance can be reversed by ß-elemene, which can alter the expression of some MDR-related miRNAs, including PTEN and Pgp in MCF-7/Adr and MCF-7/Doc in cells. It can therefore affect the exosome contents and induce the reduction of resistance transmission via exosomes.


Assuntos
Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Exossomos/metabolismo , Sesquiterpenos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Apoptose/efeitos dos fármacos , Apoptose/genética , Neoplasias da Mama/genética , Técnicas de Cocultura , Docetaxel , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/genética , Exossomos/efeitos dos fármacos , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteínas de Fluorescência Verde/metabolismo , Humanos , Luciferases/metabolismo , Células MCF-7 , Análise de Sequência com Séries de Oligonucleotídeos , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Taxoides/farmacologia
18.
PLoS One ; 10(6): e0129843, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26107945

RESUMO

The development of novel targeted therapies holds promise for conquering chemotherapy resistance, which is one of the major hurdles in current breast cancer treatment. Previous studies indicate that mitochondria uncoupling protein 2 (UCP-2) is involved in the development of chemotherapy resistance in colon cancer and lung cancer cells. In the present study we found that lower level of miR133a is accompanied by increased expression of UCP-2 in Doxorubicin-resistant breast cancer cell cline MCF-7/Dox as compared with its parental cell line MCF-7. We postulated that miR133a might play a functional role in the development of Doxorubicin-resistant in breast cancer cells. In this study we showed that: 1) exogenous expression of miR133a in MCF-7/Dox cells can sensitize their reaction to the treatment of Doxorubicin, which is coincided with reduced expression of UCP-2; 2) knockdown of UCP-2 in MCF-7/Dox cells can also sensitize their reaction to the treatment of Doxorubicin; 3) intratumoral delivering of miR133a can restore Doxorubicin treatment response in Doxorubicin-resistant xenografts in vivo, which is concomitant with the decreased expression of UCP-2. These findings provided direct evidences that the miR133a/UCP-2 axis might play an essential role in the development of Doxorubicin-resistance in breast cancer cells, suggesting that the miR133a/UCP-2 signaling cohort could be served as a novel therapeutic target for the treatment of chemotherapy resistant in breast cancer.


Assuntos
Doxorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica , Canais Iônicos/metabolismo , MicroRNAs/genética , Proteínas Mitocondriais/metabolismo , Animais , Antibióticos Antineoplásicos/uso terapêutico , Sobrevivência Celular , Feminino , Humanos , Células MCF-7 , Neoplasias Mamárias Experimentais/tratamento farmacológico , Camundongos , Camundongos Nus , Transplante de Neoplasias , Interferência de RNA , Transdução de Sinais/genética , Proteína Desacopladora 2
19.
Tuberculosis (Edinb) ; 95(3): 294-302, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25736521

RESUMO

Tuberculosis (TB) is a communicable disease of major global importance and causes metabolic disorder of the patients. In a previous study, we found that the plasma metabolite profile of TB patients differs from that of healthy control subjects based on nuclear magnetic resonance (NMR) spectroscopy. In order to evaluate the TB specificity of the metabolite profile, a total of 110 patients, including 40 with diabetes, 40 with malignancy, and 30 with community-acquired pneumonia (CAP), assessed by NMR spectroscopy, and compared to those of patients with TB. Based on the orthogonal partial least-squares discriminant analysis (OPLS-DA), the metabolic profiles of these diseases were significant different, as compared to the healthy controls and TB patients, respectively. The score plots of the OPLS-DA model demonstrated that TB was easily distinguishable from diabetes, CAP and malignancy. Plasma levels of ketone bodies, lactate, and pyruvate were increased in TB patient compared to healthy control, but lower than CAP and malignancy. We conclude that the metabolic profiles were TB-specific and reflected MTB infection. Our results strongly support the NMR spectroscopy-based metabolomics could contribute to an improved understanding of disease mechanisms and may offer clues to new TB clinic diagnosis and therapies.


Assuntos
Biomarcadores/sangue , Metabolômica/métodos , Espectroscopia de Prótons por Ressonância Magnética , Tuberculose/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Infecções Comunitárias Adquiridas/sangue , Infecções Comunitárias Adquiridas/diagnóstico , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Análise Discriminante , Feminino , Humanos , Corpos Cetônicos/sangue , Ácido Láctico/sangue , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/diagnóstico , Pneumonia/sangue , Pneumonia/diagnóstico , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Ácido Pirúvico/sangue , Tuberculose/diagnóstico , Tuberculose/microbiologia
20.
Asian Pac J Cancer Prev ; 16(3): 1105-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25735339

RESUMO

Chemoresistance is the most common cause of chemotherapy failure during breast cancer (BCA) treatment. It is generally known that the mechanisms of chemoresistance in tumors involve multiple genes and multiple signaling pathways,; if appropriate drugs are used to regulate the mechanisms at the gene level, it should be possible to effectively reverse chemoresistance in BCA cells. It has been confirmed that chemoresistance in BCA cells could be reversed by ginsenoside Rh2 (G-Rh2). Preliminary studies of our group identified some drug- resistance specific miRNA. Accordingly, we proposed that G-Rh2 could mediate drug-resistance specific miRNA and corresponding target genes through the gene regulatory network; this could cut off the drug-resistance process in tumors and enhance treatment effects. G-Rh2 and breast cancer cells were used in our study. Through pharmaceutical interventions, we could explore how G-Rh2 could inhibit chemotherapy resistance in BCA, and analyze its impact on related miRNA and target genes. Finally, we will reveal the anti-resistance molecular mechanisms of G-Rh2 from a different angle in miRNA-mediated chemoresistance signals among cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Proliferação de Células , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ginsenosídeos/farmacologia , MicroRNAs/genética , Apoptose , Western Blotting , Neoplasias da Mama/patologia , Medicamentos de Ervas Chinesas/química , Feminino , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
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