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1.
Microbiol Spectr ; 12(1): e0498122, 2024 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-38051049

RESUMEN

IMPORTANCE: Activation of the host transcription factor TFEB helps mammalian cells adapt to stresses such as starvation and infection by upregulating lysosome, autophagy, and immuno-protective gene expression. Thus, TFEB is generally thought to protect host cells. However, it may also be that pathogenic bacteria like Salmonella orchestrate TFEB in a spatio-temporal manner to harness its functions to grow intracellularly. Indeed, the relationship between Salmonella and TFEB is controversial since some studies showed that Salmonella actively promotes TFEB, while others have observed that Salmonella degrades TFEB and that compounds that promote TFEB restrict bacterial growth. Our work provides a path to resolve these apparent discordant observations since we showed that stationary-grown Salmonella actively delays TFEB after infection, while late-log Salmonella is permissive of TFEB activation. Nevertheless, the exact function of this manipulation remains unclear, but conditions that erase the conditional control of TFEB by Salmonella may be detrimental to the microbe.


Asunto(s)
Macrófagos , Serina-Treonina Quinasas TOR , Animales , Ratones , Serina-Treonina Quinasas TOR/metabolismo , Macrófagos/metabolismo , Autofagia/fisiología , Lisosomas/fisiología , Salmonella , Mamíferos
2.
Infect Immun ; 91(1): e0051822, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36533918

RESUMEN

Bacteria that colonize eukaryotic surfaces interact with numerous antimicrobial host-produced molecules, including host defense peptides, complement, and antibodies. Bacteria have evolved numerous strategies to both detect and resist these molecules, and in the Enterobacterales order of bacteria these include alterations of the cell surface lipopolysaccharide structure and/or charge and the production of proteases that can degrade these antimicrobial molecules. Here, we show that omptin family proteases from Escherichia coli and Citrobacter rodentium are regulated by the PhoPQ system. Omptin protease activity is induced by growth in low Mg2+, and deletion of PhoP dramatically reduces omptin protease activity, transcriptional regulation, and protein levels. We identify conserved PhoP-binding sites in the promoters of the E. coli omptin genes ompT, ompP, and arlC as well as in croP of Citrobacter rodentium and show that mutation of the putative PhoP-binding site in the ompT promoter abrogates PhoP-dependent expression. Finally, we show that although regulation by PhoPQ is conserved, each of the omptin proteins has differential activity toward host defense peptides, complement components, and resistance to human serum, suggesting that each omptin confers unique survival advantages against specific host antimicrobial factors.


Asunto(s)
Proteínas de Escherichia coli , Péptido Hidrolasas , Humanos , Escherichia coli/genética , Escherichia coli/metabolismo , Péptidos Antimicrobianos , Serina Endopeptidasas/genética , Péptidos Catiónicos Antimicrobianos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica , Proteínas de Escherichia coli/genética
3.
FEMS Microbiol Lett ; 369(1)2022 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-36208952

RESUMEN

Adherent-invasive Escherichia coli (AIEC) are isolated from inflammatory bowel disease (IBD) patients at a higher rate than from control patients. Using a collection of E. coli strains collected from Crohn's disease (CD), ulcerative colitis (UC), or non-IBD control patients, antibiotic and resistance to the antimicrobial peptides HBD-3 and LL-37 was assessed. Carriage of bacterial-encoded omptin protease genes was assessed by PCR and omptin protease activity was measured using a whole-cell based fluorescence assay. Elevated resistance to antibiotics and host defense peptides in IBD-associated AIEC were observed. IBD-associated strains showed increased (but statistically non-significant) antibiotic resistance. CD-associated strains showed greater (but statistically non-significant) resistance to HBD3-mediated killing while UC-associated strains showed statistically greater resistance to LL-37 mediated killing. High-level resistance to LL-37 was associated with carriage of omptin protease genes and with increased omptin protease activity. Antimicrobial host defense peptide resistance may be an adaptive feature of AIEC leading to enhanced pathogenesis during the initiation or progression of IBD.


Asunto(s)
Colitis Ulcerosa , Enfermedad de Crohn , Infecciones por Escherichia coli , Enfermedades Inflamatorias del Intestino , Humanos , Escherichia coli/genética , Péptidos Catiónicos Antimicrobianos/farmacología , Adhesión Bacteriana/genética , Enfermedad de Crohn/patología , Péptido Hidrolasas , Mucosa Intestinal
4.
Inflamm Bowel Dis ; 25(1): 33-44, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30321333

RESUMEN

Inflammatory bowel diseases are becoming increasingly common throughout the world, both in developed countries and increasingly in rapidly developing countries. Multiple lines of evidence point to a role for the microbial composition of the gastrointestinal tract in the etiology of IBD, but to date, attempts to define a specific microbial cause for IBD have proved unsuccessful. Microbial 16S rRNA profiling shows that IBD patients have elevated levels of Enterobacteriaceae, in particular Escherichia coli, and reduced levels of Faecalibacterium prausnitzii. The observed E. coli have been assigned to a specific pathovar, adherent-invasive E. coli (AIEC). Adherent-invasive E. coli are a genomically heterogenous group, and whereas many groups have attempted to identify specific genetic markers that differentiate AIEC from non-AIEC strains, very few concrete genetic associations have been uncovered. Here, we highlight the advantages of applying a phenotyping approach to the study of these organisms, rather than solely depending on a sequencing or genomic-based screening strategy because virulence-associated phenotypes exhibit behaviors of emergent systems. In this respect, attempts at genetic reductionism are prone to failure because there are numerous metabolic, regulatory or genetic paths that can underlie these virulence-associated behaviors. Here, we review these IBD-associated phenotypes in E. coli and make recommendations for experimental approaches to advance our understanding of IBD-associated bacteria more generally. With advances in high-throughput screening and nongenetically based metabolomic characterization of IBD-associated bacteria, we anticipate a fuller understanding of how altered microbial communities contribute to the development of IBD.


Asunto(s)
Infecciones por Escherichia coli/complicaciones , Escherichia coli/patogenicidad , Enfermedades Inflamatorias del Intestino/etiología , Infecciones por Escherichia coli/microbiología , Humanos , Enfermedades Inflamatorias del Intestino/patología , Fenotipo , Pronóstico
5.
World J Gastroenterol ; 22(8): 2621-9, 2016 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-26937150

RESUMEN

AIM: To evaluate the full-spectrum endoscopy (FUSE) colonoscopy system as the first report on the utility thereof in a Korean population. METHODS: We explored the efficacy of the FUSE colonoscopy in a retrospective, single-center feasibility study performed between February 1 and July 20, 2015. A total of 262 subjects (age range: 22-80) underwent the FUSE colonoscopy for colorectal cancer screening, polyp surveillance, or diagnostic evaluation. The cecal intubation success rate, the polyp detection rate (PDR), the adenoma detection rate (ADR), and the diverticulum detection rate (DDR), were calculated. Also, the success rates of therapeutic interventions were evaluated with biopsy confirmation. RESULTS: All patients completed the study and the success rates of cecal and terminal ileal intubation were 100% with the FUSE colonoscope; we found 313 polyps in 142 patients and 173 adenomas in 95. The overall PDR, ADR and DDR were 54.2%, 36.3%, and 25.2%, respectively, and were higher in males, and increased with age. The endoscopists and nurses involved considered that the full-spectrum colonoscope improved navigation and orientation within the colon. No colonoscopy was aborted because of colonoscope malfunction. CONCLUSION: The FUSE colonoscopy yielded a higher PDR, ADR, DDR than did traditional colonoscopy, without therapeutic failure or complications, showing feasible, effective, and safe in this first Korean trial.


Asunto(s)
Adenoma/patología , Neoplasias del Colon/patología , Pólipos del Colon/patología , Colonoscopía , Divertículo del Colon/patología , Adenoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Neoplasias del Colon/terapia , Pólipos del Colon/terapia , Colonoscopios , Colonoscopía/efectos adversos , Colonoscopía/instrumentación , Divertículo del Colon/terapia , Diseño de Equipo , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , República de Corea , Estudios Retrospectivos , Adulto Joven
6.
Korean J Intern Med ; 30(3): 308-15, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25995661

RESUMEN

BACKGROUND/AIMS: (18)F-Fluorodeoxyglucose positron-emission tomography ((18)F-FDG PET) has been used to assess the biological behavior of hepatocellular carcinoma (HCC). In this study, we investigated the usefulness of (18)F-FDG PET for predicting tumor progression and survival in patients with intermediate Barcelona Clinic Liver Cancer (BCLC) intermediate-stage HCC treated by transarterial chemoembolization (TACE). METHODS: From February 2006 to March 2013, 210 patients treated with TACE, including 77 patients with BCLC intermediate-stage HCC, underwent examination by (18)F-FDG PET. (18)F-FDG uptake was calculated based on the tumor maximum (Tmax) standardized uptake value (SUV), the liver mean (Lmean) SUV, and the ratio of the Tmax SUV to the Lmean SUV (Tmax/Lmean). RESULTS: The mean follow-up period for the 77 patients (52 males, 25 females; average age, 63.3 years) was 22.2 months. The median time to progression of HCC in patients with a low Tmax/Lmean (< 1.83) and high Tmax/Lmean (≥ 1.83) was 17 and 6 months, respectively (p < 0.001). The median overall survival time of patients with a low and high Tmax/Lmean was 44 and 14 months, respectively (p = 0.003). Multivariate analysis revealed that the Tmax/Lmean was an independent predictor of overall survival (hazard ratio [HR], 1.96; 95% confidence interval [CI], 1.210 to 3.156; p = 0.006) and tumor progression (HR, 2.05; 95% CI, 1.264 to 3.308; p = 0.004). CONCLUSIONS: (18)F-FDG uptake calculated by the Tmax/Lmean using PET predicted tumor progression and survival in patients with BCLC intermediate-stage HCC treated by TACE.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/cirugía , Quimioembolización Terapéutica , Fluorodesoxiglucosa F18 , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/cirugía , Tomografía de Emisión de Positrones , Radiofármacos , Anciano , Carcinoma Hepatocelular/mortalidad , Quimioembolización Terapéutica/efectos adversos , Quimioembolización Terapéutica/mortalidad , Progresión de la Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Imagen Multimodal , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
7.
Nucl Med Commun ; 36(4): 319-27, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25564069

RESUMEN

OBJECTIVE: The limited studies with 18F-fluorodeoxyglucose (18F-FDG)-PET reported results and interpretations that differed between hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (IHCC). We investigated the correlation between preoperative PET results and postoperative prognosis, including early (time-to-recurrence<6 months) tumor recurrence, and histopathological tumor differentiation in patients who had undergone surgery for primary malignant intrahepatic tumors, including HCC and IHCC. MATERIALS AND METHODS: We retrospectively reviewed 357 patients who had undergone curative surgery for malignant hepatic tumors, including primary HCC or IHCC, other than Klatskin tumors at a tertiary academic hospital between January 2005 and June 2012. All patients had undergone an 18F-FDG PET/computed tomography scan preoperatively and the maximum standardized uptake value of the tumor (max SUV tumor) and the tumor-to-nontumor SUV ratio (TNR) were calculated from 18F-FDG uptake. Histopathological differentiation grading was confirmed postoperatively. RESULTS: Among the patients, 115 cases with primary malignant intrahepatic tumors fulfilled the inclusion criteria. On univariate analysis, preoperative max SUV tumor and TNR showed a correlation with the overall and early tumor recurrence of HCC, but only max SUV tumor was associated with overall and early recurrence of IHCC (P<0.05). When considering postoperative histopathological differentiation, a correlation between max SUV tumor and TNR with HCC and between max SUV tumor and IHCC was found (P<0.05). However, on multivariate analysis, only early recurrence was associated with TNR in HCC and with max SUV tumor in IHCC. CONCLUSION: A preoperative 18F-FDG PET scan can be considered a useful reference for postoperative tumor recurrence and histopathological differentiation in cases of primary malignant intrahepatic tumors. 18F-FDG PET scan results should be interpreted separately for malignant liver tumors.


Asunto(s)
Neoplasias de los Conductos Biliares/diagnóstico por imagen , Carcinoma Hepatocelular/diagnóstico por imagen , Colangiocarcinoma/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Neoplasias Hepáticas/diagnóstico por imagen , Tomografía de Emisión de Positrones , Periodo Preoperatorio , Adulto , Anciano , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/cirugía , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Colangiocarcinoma/patología , Colangiocarcinoma/cirugía , Diagnóstico Diferencial , Femenino , Humanos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Análisis Multivariante , Pronóstico , Recurrencia , Estudios Retrospectivos
8.
Korean J Women Health Nurs ; 21(4): 321-331, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37684835

RESUMEN

PURPOSE: Purpose of this study was to identify the effect of structured information on immediate preoperative anxiety and uncertainty for women undergoing total laparoscopic hysterectomy. METHODS: Sixty women who were admitted for total laparoscopic hysterectomy were recruited at a university hospital in Gyeonggi-do from June to October 2014. Thirty women were assigned to either the experimental or the control group. Women in the experimental group were provided structured information, which consisted of visual and auditory materials about surgical preparation and process, practical experience on devices such as IV-PCA pump and Inspiro-meter and actual experience on route to go to the operating room. State-anxiety, uncertainty, and blood pressure and pulse rate as biological indicators were measured before and after the intervention to examine the effect. RESULTS: Significant group differences were found on state anxiety, uncertainty, including ambiguity, inconsistency, and unpredictability at the holding area. There was a significant difference on pulse rate in the operating room between the two groups. CONCLUSION: Findings demonstrated that the structured information provided for women undergoing laparoscopic hysterectomy preoperatively was effective on immediate preoperative anxiety and uncertainty. Nurses may contribute to decreasing patients' anxiety and uncertainty by utilizing this structured information preoperatively.

9.
Intest Res ; 12(2): 139-45, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25349581

RESUMEN

BACKGROUND/AIMS: Colorectal cancer (CRC) develops from colonic adenomas. Type 2 diabetes mellitus (DM) is associated with a higher risk of CRC and metformin decreases CRC risk. However, it is not certain if metformin affects the development of colorectal polyps and adenomas. This study aimed to elucidate if metforminaffects the incidence of colonic polyps and adenomas in patients with type 2 DM. METHODS: Of 12,186 patients with type 2 DM, 3,775 underwent colonoscopy between May 2001 and March 2013. This study enrolled 3,105 of these patients, and divided them in two groups: 912 patients with metformin use and 2,193 patients without metformin use. Patient clinical characteristics, polyp and adenoma detection rate in the two groups were analyzed retrospectively. RESULTS: The Colorectal polyp detection rate was lower in the metformin group than in the non-meformin group (39.4% vs. 62.4%, P<0.01). Colorectal adenoma detection rate was significantly lower in the metformin group than in the non-metformin group (15.2% vs. 20.5%, P<0.01). Fewer advanced adenomas were detected in the metformin group than in the non-metformin group (12.2% vs. 22%, P<0.01). Multivariate analysis identified age, sex, Body mass index and metformin use as factors associated with polyp incidence, whereas only metforminwas independently associated with decreased adenoma incidence (Odd ratio=0.738, 95% CI=0.554-0.983, P=0.03). CONCLUSIONS: In patients with type 2 DM, metformin reduced the incidence of adenomas that may transform into CRC. Therefore, metformin may be useful for the prevention of CRC in patients with type 2 DM.

10.
Scand J Gastroenterol ; 49(8): 967-73, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24874189

RESUMEN

OBJECTIVE: Self-expandable metal stents (SEMSs) have been used as palliative treatment or bridge to surgery for obstructions caused by colorectal cancer (CRC). We assessed the long-term outcomes of palliative SEMSs and evaluated the risk factors influencing complications. MATERIALS AND METHODS: One hundred and seventy-five patients underwent SEMS placement for acute malignant colorectal obstruction. Of the 72 patients who underwent palliative treatment for primary CRC, 30 patients received chemotherapy (CT) for primary cancer (CT group) and 42 underwent best supportive treatment (BST) without CT (BST group). RESULTS: There was a significant difference in late migration between the CT group and the BST group (20.0% in CT group, 2.4% in BST group, p = 0.018). Response to CT influenced the rate of late obstruction (0% in disease control, 35.7% in disease progression, p = 0.014). However, late obstruction was not associated with stent properties, such as diameter or type (≤22 mm vs. >22 mm, 13.5% vs. 14.3%, p = 1.00; uncovered stent vs. covered stent, 15.5% vs. 7.1%, p = 0.675) and migration (≤22 mm vs. >22 mm, 16.2% vs. 2.9%, p = 0.108; uncovered stent vs. covered stent, 8.6% vs. 14.3%, p = 0.615) in palliative SEMS. CONCLUSION: The administration of CT increases the rate of stent migration, and disease control by CT can reduce the risk of obstruction by maintaining the luminal patency of palliative SEMSs.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/terapia , Obstrucción Intestinal/etiología , Obstrucción Intestinal/terapia , Cuidados Paliativos , Stents , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/mortalidad , Progresión de la Enfermedad , Endoscopía Gastrointestinal , Femenino , Estudios de Seguimiento , Humanos , Obstrucción Intestinal/diagnóstico , Obstrucción Intestinal/mortalidad , Masculino , Metales , Persona de Mediana Edad , Cuidados Paliativos/métodos , República de Corea/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento
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