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1.
Lett Appl Microbiol ; 73(4): 453-459, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34214198

RESUMEN

Fusarium wilt is caused by the soil-inhabiting fungus Fusarium oxysporum ff. spp. and is one of the most devastating plant diseases, resulting in losses and decreasing the quality and safety of agricultural crops. We recently reported the structures and biochemical properties of two biotin-binding proteins, streptavidin C1 and C2 (isolated from Streptomyces cinnamonensis strain KPP02129). In the present study, the potential of the biotin-binding proteins as antifungal agent for Fusarium wilt pathogens was investigated using recombinant streptavidin C1 and C2. The minimum inhibitory concentration of streptavidin C2 was found to be 16 µg ml-1 for inhibiting the mycelial growth of F. oxysporum f.sp. cucumerinum and F. oxysporum f.sp. lycopersici, while that of streptavidin C1 was found to be 64 µg ml-1 . Compared with the nontreated control soil, the population density of F. oxysporum f.sp. lycopersici in the soil was reduced to 49·5% and 39·6% on treatment with streptavidin C1 (500 µg ml-1 ) and C2 (500 µg ml-1 ), respectively. A greenhouse experiment revealed that Fusarium wilt of tomato plants was completely inhibited on soil drenching using a 50-ml culture filtrate of the streptavidin-producing strain KPP02129.


Asunto(s)
Fusarium , Antifúngicos/farmacología , Enfermedades de las Plantas , Estreptavidina , Streptomyces
2.
Opt Express ; 28(26): 38942-38948, 2020 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-33379452

RESUMEN

A novel tunable transmitter structure based on liquid crystal filter, to the best of our knowledge, is presented. The structure is designed for application to 5G fronthaul and supports 25 Gbps dense wavelength division multiplexing (WDM) transmission and tunable range of 35 nm. The design takes into account easy change of operation band over coarse WDM grid. Prototype samples are developed to test feasibility of the design.

3.
Skin Res Technol ; 24(3): 367-370, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29393550

RESUMEN

BACKGROUND: Increasing the number of enlarged pores causes cosmetic problems. The difference in the number of enlarged pores according to facial site, age, and sex is unclear. OBJECTIVE: To analyze the distribution of the number of enlarged pores according to facial site, age, and sex. METHODS AND MATERIALS: We analyzed the number of the enlarged pores and the percentage of wrinkles in the nose, forehead, and cheek from 434 polarized images. The measurement results were analyzed according to site, age, and sex. Relationship between enlarged pore counts and wrinkle severity was also analyzed. The study was conducted by using DermaVision,™ which can take cross-polarization, parallel polarization, and ultraviolet light images. RESULTS: The enlarged pores of the nose and forehead were more prominent than in the cheeks. Pore counts were increased with age, and the increment was significant between the 30's and 40's. There was no significant difference by gender. Enlarged pore counts were related to wrinkle severity. CONCLUSIONS: The number of enlarged pores differs depending on body site and increased with age. The enlarged pore counts correlate with wrinkle severity and the correlation varies depending on the body site.


Asunto(s)
Cara , Folículo Piloso , Glándulas Sebáceas , Envejecimiento de la Piel , Adulto , Factores de Edad , Anciano , Mejilla , Femenino , Frente , Humanos , Masculino , Persona de Mediana Edad , Nariz , Factores Sexuales , Piel
4.
Int Endod J ; 50(3): 260-270, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26865394

RESUMEN

AIM: To investigate the role of nitric oxide (NO)-induced autophagy in human dental pulp cells (HDPCs) and the involvement of AMP-activated protein kinase (AMPK) pathway. METHODOLOGY: The MTT assay was used to determine the cytotoxic effect of the NO donor sodium nitroprusside (SNP) in HDPCs. Apoptosis was detected by means of the terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assay, and apoptosis- or autophagy-related signal molecules were observed by Western blot analysis. Acidic autophagolysosomal vacuoles were stained with acridine orange to detect autophagy in the presence of 3-methyladenine (3MA) used to inhibit autophagy. To explore the mechanism underlying autophagy and its protective role against apoptosis, compound C, the chemical AMPK inhibitor, was used. Statistical analysis was performed using Student's t-test or analysis of variance (anova) followed by the Student-Newman-Keuls test (P < 0.05). RESULTS: SNP decreased viability of the HDPCs in a dose- and time-dependent manner. Exposing the HDPCs to SNP increased the levels of p62 and LC3-II, the typical markers of autophagy, and increased the number of acidic autophagolysosomal vacuoles, indicating the appearance of autophagy as detected by acridine orange staining (P < 0.05). Pre-treatment with 3MA decreased cell viability but increased cleaved poly(ADP-ribose) polymerase (PARP) and caspase-3, apoptosis indicators, in the SNP-treated HDPCs (P < 0.05). SNP activated AMPK/ULK signalling, whilst the inhibition of AMPK by compound C enhanced apoptotic cell death induced by SNP in the HDPCs (P < 0.05). CONCLUSION: NO induced autophagy with AMPK activation, which plays a role in the survival of HDPCs against NO-induced apoptosis.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Pulpa Dental/metabolismo , Óxido Nítrico/farmacología , Autofagia/fisiología , Células Cultivadas , Pulpa Dental/citología , Humanos , Serina-Treonina Quinasas TOR/metabolismo
5.
J Helminthol ; 91(5): 642-646, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27628641

RESUMEN

Sparganosis is one of the top three tissue-dwelling heterologous helminthic diseases, along with cysticercosis and paragonimiasis, in Korea. Due to a lack of effective early diagnosis and treatment methods, this parasitic disease is regarded as a public health threat. This study evaluated reactivity, against sparganum extracts, of sera from inhabitants of Cheorwon-gun, Goseong-gun and Ongjin-gun in Korea. The sera from 836 subjects were subjected to enzyme-linked immunosorbent assay and immunoblot analysis. The sera from 18 (5.8%) and 15 (5.1%) inhabitants in Cheorwon-gun (n = 312) and Goseong-gun (n = 294), respectively, exhibited highly positive reactions to the sparganum antigen, whereas only two (0.9%) inhabitants in Ongjin-gun (n = 230) showed positivity. We sought antigenic proteins for serodiagnosis of positive sera by immunoproteomic approaches. Total sparganum lysates were separated by two-dimensional electrophoresis and then subjected to immunoblot analysis with mixed sparganosis-positive sera. We found seven antigenic spots and identified paramyosin as an antigenic protein by liquid chromatography-mass spectrometry. By two-dimensional (2D)-based mass analysis and immunoblotting against sparganosis-positive sera, paramyosin was identified as a candidate antigen for serodiagnosis of sparganosis.


Asunto(s)
Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/inmunología , Pruebas Serológicas/métodos , Esparganosis/diagnóstico , Plerocercoide/inmunología , Tropomiosina/inmunología , Animales , Antígenos Helmínticos/análisis , Cromatografía Liquida , Electroforesis en Gel Bidimensional , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Immunoblotting , Espectrometría de Masas , Proteoma/análisis , República de Corea , Plerocercoide/química , Tropomiosina/análisis
6.
J Appl Microbiol ; 121(3): 800-10, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27111464

RESUMEN

AIM: Nonalcoholic hepatic fat accumulation has been hypothesized to be associated with alterations in gut microbiota composition, although mechanistic explanations for this link are largely insufficient. The aim of this study was to elucidate the microbiota-driven mechanisms involved in the development of nonalcoholic hepatic steatosis. METHODS AND RESULTS: Ob/ob mice and their wild-type lean control mice were fed an AIN-93G diet for 12 weeks. Faecal microbiota composition, faecal bile acid (BA) profile and intestinal and hepatic markers of BA metabolism were analysed. Ob/ob mice had significantly less faecal taurine-conjugated BAs compared to their lean controls. The proportions of butyrate-producing bacteria were lower in ob/ob mice compared to those in lean mice. Intestinal expression of farnesoid X receptor (FXR) mRNA was significantly higher, whereas hepatic expression of cholesterol-7α-hydroxylase 1 (CYP7A1) and small heterodimer partner (SHP) were significantly lower in ob/ob mice compared to those in control mice. CONCLUSION: Microbiota-associated BAs deconjugation may induce nonalcoholic fatty liver disease (NAFLD) by activating intestinal FXR signalling and blocking hepatic FXR-SHP pathway, thereby accelerating fat synthesis. SIGNIFICANCE AND IMPACT OF THE STUDY: We provided evidences that changes in the gut microbiota and their metabolites can alter the profile of BAs, thereby providing a mechanism by which an altered microbiota profile contributes to the development of NAFLD.


Asunto(s)
Ácidos y Sales Biliares/metabolismo , Hígado Graso/microbiología , Microbioma Gastrointestinal , Intestinos/microbiología , Animales , Colesterol 7-alfa-Hidroxilasa/genética , Colesterol 7-alfa-Hidroxilasa/metabolismo , Modelos Animales de Enfermedad , Hígado Graso/enzimología , Hígado Graso/genética , Hígado Graso/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Metabolismo de los Lípidos , Hígado/enzimología , Hígado/metabolismo , Masculino , Ratones , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo
8.
Genes Immun ; 15(4): 233-40, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24598798

RESUMEN

SHIP-1 has an important role in controlling immune cell function through its ability to downmodulate PI3K signaling pathways that regulate cell survival and responses to stimulation. Mice deficient in SHIP-1 display several chronic inflammatory phenotypes including antibody-mediated autoimmune disease, Crohn's disease-like ileitis and a lung disease reminiscent of chronic obstructive pulmonary disease. The ileum and lungs of SHIP-1-deficient mice are infiltrated at an early age with abundant myeloid cells and the mice have a limited lifespan primarily thought to be due to the consolidation of lungs with spontaneously activated macrophages. To determine whether the myeloid compartment is the key initiator of inflammatory disease in SHIP-1-deficient mice, we examined two independent strains of mice harboring myeloid-restricted deletion of SHIP-1. Contrary to expectations, conditional deletion of SHIP-1 in myeloid cells did not result in consolidating pneumonia or segmental ileitis typical of germline SHIP-1 deficiency. In addition, other myeloid cell abnormalities characteristic of germline loss of SHIP-1, including flagrant splenomegaly and enhanced myelopoiesis, were absent in mice lacking SHIP-1 in myeloid cells. This study indicates that the spontaneous inflammatory disease characteristic of germline SHIP-1 deficiency is not initiated solely by LysM-positive myeloid cells but requires the simultaneous loss of SHIP-1 in other hematolymphoid lineages.


Asunto(s)
Pulmón/inmunología , Activación de Macrófagos , Macrófagos/inmunología , Mielopoyesis/inmunología , Monoéster Fosfórico Hidrolasas/inmunología , Neumonía/inmunología , Animales , Enfermedad Crónica , Íleon/enzimología , Íleon/inmunología , Inflamación/enzimología , Inflamación/inmunología , Inflamación/patología , Inositol Polifosfato 5-Fosfatasas , Pulmón/enzimología , Pulmón/patología , Macrófagos/enzimología , Macrófagos/patología , Ratones , Ratones Noqueados , Mielopoyesis/genética , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/inmunología , Fosfatidilinositol 3-Quinasas/metabolismo , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatasas , Monoéster Fosfórico Hidrolasas/genética , Monoéster Fosfórico Hidrolasas/metabolismo , Neumonía/enzimología , Neumonía/genética
9.
Front Robot AI ; 11: 1374999, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38651053

RESUMEN

With the growing demand for robots in the industrial field, robot-related technologies with various functions have been introduced. One notable development is the implementation of robots that operate in collaboration with human workers to share tasks, without the need of any physical barriers such as safety fences. The realization of such collaborative operations in practice necessitates the assurance of safety if humans and robots collide. Thus, it is important to establish criteria for such collision scenarios to ensure robot safety and prevent injuries. Collision safety must be ensured in both pinching (quasi-static contact) and impact (transient contact) situations. To this end, we measured the force pain thresholds associated with impacts and evaluated the biomechanical limitations. This measurements were obtained through clinical trials involving physical collisions between human subjects and a device designed for generating impacts, and the force pain thresholds associated with transient collisions between humans and robots were analyzed. Specifically, the force pain threshold was measured at two different locations on the bodies of 37 adults aged 19-32 years, using two impactors with different shapes. The force pain threshold was compared with the results of other relevant studies. The results can help identify biomechanical limitations in a precise and reliable manner to ensure the safety of robots in collaborative applications.

10.
Eur Radiol ; 23(4): 1150-7, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22868482

RESUMEN

OBJECTIVE: To compare three-dimensional (3D) T2-weighted turbo spin-echo (TSE) with multiplanar two-dimensional (2D) T2-weighted TSE for the evaluation of invasive cervical carcinoma. METHODS: Seventy-five patients with cervical carcinoma underwent MRI of the pelvis at 3.0 T, using both 5-mm-thick multiplanar 2D (total acquisition time = 12 min 25 s) and 1-mm-thick coronal 3D T2-weighted TSE sequences (7 min 20 s). Quantitative analysis of signal-to-noise ratio (SNR) and qualitative analysis of image quality were performed. Local-regional staging was performed in 45 patients who underwent radical hysterectomy. RESULTS: The estimated SNR of cervical carcinoma and the relative tumour contrast were significantly higher on 3D imaging (P < 0.0001). Tumour conspicuity was better with the 3D sequence, but the sharpness of tumour margin was better with the 2D sequence. No significant difference in overall image quality was noted between the two sequences (P = 0.38). There were no significant differences in terms of the diagnostic accuracy, sensitivity, and specificity of parametrial invasion, vaginal invasion, and lymph node metastases. CONCLUSION: Multiplanar reconstruction 3D T2-weighted imaging is largely equivalent to 2D T2-weighted imaging for overall image quality and staging accuracy of cervical carcinoma with a shorter MR data acquisition, but has limitations with regard to the sharpness of the tumour margin.


Asunto(s)
Algoritmos , Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Imagen por Resonancia Magnética/métodos , Neoplasias Uterinas/patología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Aumento de la Imagen/métodos , Persona de Mediana Edad , Estadificación de Neoplasias , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
QJM ; 116(3): 197-204, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36200913

RESUMEN

BACKGROUND: Apelin is an endogenous neuropeptide that binds to the G-protein-coupled receptor (APJ) and participates in a variety of physiological processes in the heart, lungs and other peripheral organs. Intriguingly, [Pyr1]-Apelin-13, a highly potent pyroglutamic form of apelin, has the potential to bind to and be degraded by angiotensin-converting enzyme 2 (ACE2). ACE2 is known to operate as a viral receptor in the early stages of severe acute respiratory coronavirus (SARS-CoV-2) infection. AIM: This study aimed to determine if apelin protects against SARS-CoV-2 infection by inhibiting ACE2 binding to SARS-CoV-2 spike protein. DESIGN AND METHODS: To determine whether [Pyr1]-Apelin-13 inhibits ACE2 binding to the SARS-CoV-2 spike protein (S protein), we performed a cell-to-cell fusion assay using ACE2-expressing cells and S protein-expressing cells and a pseudovirus-based inhibition assay. We then analyzed publicly available transcriptome data while focusing on the beneficial effects of apelin on the lungs. RESULTS: We found that [Pyr1]-Apelin-13 inhibits cell-to-cell fusion mediated by ACE2 binding to the S protein. In this experiment, [Pyr1]-Apelin-13 protected human bronchial epithelial cells, infected with pseudo-typed lentivirus-producing S protein, against viral infection. In the presence of [Pyr1]-Apelin-13, the level of viral spike protein expression was also reduced in a concentration-dependent manner. Transcriptome analysis revealed that apelin may control inflammatory responses to viral infection by inhibiting the nuclear factor kappa B pathway. CONCLUSION: Apelin is a potential therapeutic candidate against SARS-CoV-2 infection.


Asunto(s)
COVID-19 , Humanos , Enzima Convertidora de Angiotensina 2/farmacología , SARS-CoV-2/metabolismo , Apelina/farmacología , Tratamiento Farmacológico de COVID-19 , Peptidil-Dipeptidasa A/metabolismo
13.
Clin Radiol ; 65(12): 967-73, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21070899

RESUMEN

AIM: To determine whether radiologists can recognize images retouched to include sham lesions. MATERIALS AND METHODS: Ten representative key images were selected of aortic dissection, hepatocellular carcinoma, renal cell carcinoma, colon cancer, liver metastasis, hepatic cyst, gallbladder stones, splenic artery aneurysm, adrenal adenoma, and stomach cancer from abdominal computed tomography (CT) imaging performed in 2008. Five of the key images were replaced with retouched images using image-editing software. The time to complete retouching was recorded for each image. Radiologists were requested to make a diagnosis for the 10 images, and were then asked to identify possible retouched images. The time taken to reach a decision in each case was recorded. Thirty radiologists (13 residents and 17 attending radiologists) participated as reviewers. RESULTS: The time to complete retouching was 15.2±3.15 min. None of the reviewers recognized that some images were retouched during diagnosis. The rate of correct diagnosis was 90% (range 71.7-100%). After reviewers were informed of possible image retouching, the detection rate of retouched images was 50% (40-58.3%). This rate was statistically the same as random choice (p=0.876). There was no significant difference between residents and attending radiologists in the detection rate of retouched images (p=0.786). The time to diagnosis and the time to detection of the retouched images were 15 (14-17) and 6 (5-7) min, respectively. CONCLUSION: Digital images can be easily retouched, and radiologists have difficulty in identifying retouched images. Radiologists should be aware of the potential fraudulent use of retouched images.


Asunto(s)
Seguridad Computacional , Procesamiento de Imagen Asistido por Computador , Intensificación de Imagen Radiográfica/normas , Sistemas de Información Radiológica/normas , Decepción , Fraude , Humanos , Formulario de Reclamación de Seguro/legislación & jurisprudencia , Internado y Residencia , Radiología , Sistemas de Información Radiológica/legislación & jurisprudencia , República de Corea , Programas Informáticos , Factores de Tiempo , Tomografía Computarizada por Rayos X
14.
Lett Appl Microbiol ; 50(5): 445-51, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20302599

RESUMEN

AIMS: The objective of this study was to evaluate recombinant 56-kDa outer membrane protein as a potential inhibitor to infection from Orientia tsutsugamushi. METHODS AND RESULTS: The 56-kDa protein was cloned and expressed in an Escherichia coli system, and the degree of target cell attachment to immobilized 56-kDa protein was measured in a cell adhesion assay. The results showed that the 56-kDa protein has an ability to attach HeLa cells. Furthermore, treatment of target cells with a truncated 56-kDa 1-418 (amino acid residues) protein inhibited target cell infection by O. tsutsugamushi, demonstrated with an indirect immunofluorescence antibody assay. CONCLUSIONS: The truncated 56-kDa protein (a.a. 1-418) plays an important role in O. tsutsugamushi infection, and the 56-kDa protein could be useful and effective in the inhibition of O. tsutsugamushi attachment and infection. SIGNIFICANCE AND IMPACT OF THE STUDY: The attachment of the 56-kDa protein to target cells was directly determined by in vitro adherence test, and the invasion of target cells by O. tsutsugamushi was inhibited by treating the target cells with a truncated 56-kDa protein.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/genética , Proteínas de la Membrana Bacteriana Externa/metabolismo , Regulación hacia Abajo , Orientia tsutsugamushi/fisiología , Tifus por Ácaros/microbiología , Animales , Adhesión Celular , Células HeLa , Humanos , Ratones , Orientia tsutsugamushi/genética , Unión Proteica , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Tifus por Ácaros/fisiopatología
15.
Clin Microbiol Infect ; 14(2): 174-7, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18070125

RESUMEN

A case-control study was conducted involving 156 patients with scrub typhus and 130 controls. Three factors were associated significantly with the risk of developing scrub typhus: engaging in fruit farming (OR 2.44; 95% CI 1.04-5.69), gathering chestnuts (OR 2.05; 95% CI 1.09-3.87) and taking breaks in areas adjacent to agricultural operations (OR 3.06; 95% CI 1.50-6.22). In contrast, receiving information or educational materials concerning the prevention of scrub typhus had a protective effect (OR 0.45; 95% CI 0.24-0.83). These results suggest that a health education programme will lower the risk of developing scrub typhus when applied to high-risk groups.


Asunto(s)
Orientia tsutsugamushi/patogenicidad , Tifus por Ácaros/epidemiología , Tifus por Ácaros/prevención & control , Adulto , Anciano , Agricultura , Animales , Vectores Arácnidos/microbiología , Estudios de Casos y Controles , Femenino , Educación en Salud , Humanos , Corea (Geográfico)/epidemiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Tifus por Ácaros/transmisión , Trombiculidae/microbiología
16.
Transplant Proc ; 40(5): 1488-91, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18589135

RESUMEN

BACKGROUND: To evaluate the correlation of postoperative portal venous velocity (PVV) and portal venous flow (PVF) with the degree of short-term graft regeneration in recipients of living donor liver transplantation (LDLT). MATERIALS AND METHODS: Between August 2005 and April 2006, we performed 44 adult-to-adult LDLTs with right-lobe grafts, of whom 31 recipients were included in this study. Doppler ultrasonography was used to measure PVV (cm/s) and PVF (mL/min) on postoperative days (POD) 1, 3, and 5 or 6. Portal venous velocity index (PVI) was defined as the ratio of PVV to graft weight (GW), and portal flow volume index (PFI) as the ratio of PVF to GW. Graft regeneration rate (GRR), defined as the ratio of the volume of regenerated graft to GW, was estimated by dividing computed tomography volumetry at POD 7 by GW measured after retrieval of the graft. We analyzed the relationship between GRR and PVV, PVF, PVI, and PFI. RESULTS: GW ranged between 528 g and 1040 g (mean = 735 g) and GRR ranged between 118% and 278% (mean = 172%). Although neither PVV nor PVF correlated with GRR, PVI and PFI at POD 1 (P = .009) and PFI at POD 5 or 6 (P = .012) significantly correlated with GRR at POD 7. CONCLUSION: PVI and PFI at POD 1 are useful indicators to predict short-term graft regeneration in recipients of LDLT.


Asunto(s)
Velocidad del Flujo Sanguíneo , Regeneración Hepática/fisiología , Trasplante de Hígado/fisiología , Vena Porta/fisiología , Adulto , Hepatectomía , Humanos , Hígado/anatomía & histología , Cirrosis Hepática/cirugía , Fallo Hepático/cirugía , Donadores Vivos , Tamaño de los Órganos , Regeneración , Estudios Retrospectivos
17.
Clin Microbiol Infect ; 12(3): 254-61, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16451413

RESUMEN

This study characterised the population structure of Legionella pneumophila by comparing the rpoB (300-bp) and dotA (360-bp) sequences of 267 isolates (18 reference strains, 149 Korean isolates and 100 Japanese isolates). In addition to the six clonal subgroups established previously, four subgroups, P-V to P-VIII, were identified. Subgroupings based on rpoB and dotA sequences were found to correlate with the source of the isolates, and this data may be useful for future epidemiological studies. Fourteen (five Korean and nine Japanese) isolates showed incongruent subgroupings in the rpoB and dotA trees, suggesting that genetic exchange among subgroups, and even among subspecies, may occur frequently in nature.


Asunto(s)
Proteínas Bacterianas/genética , Proteínas Portadoras/genética , ARN Polimerasas Dirigidas por ADN/genética , Genes Bacterianos , Legionella pneumophila/genética , Proteínas de la Membrana/genética , Variación Genética , Japón , Corea (Geográfico) , Legionella pneumophila/clasificación , Datos de Secuencia Molecular , Especificidad de la Especie
18.
Cancer Lett ; 145(1-2): 57-64, 1999 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-10530770

RESUMEN

Chlorophyllin (CHL), a water-soluble derivative of chlorophyll, has been used for the treatment of several abnormal human conditions without apparent toxicity. Recent studies have revealed that CHL has the excellent chemopreventive potential. In the present investigation, we have found the inhibitory activities of CHL against 7,12-dimethylbenz[a]anthracene (DMBA)-induced mutagenesis in Salmonella typhimurium TA100 and also on DMBA-initiated and 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-promoted mouse skin tumor formation. The incidence and the multiplicity of skin tumors were not significantly decreased in mice by a single topical application of CHL prior to the DMBA treatment, but there was a marked suppression of papillomagenesis in mice treated with CHL during the promotional stage. Furthermore, the formation of DMBA-induced papillomagenesis was reduced in all mice that had received CHL for 6 weeks following treatment with TPA for 6, 18 and 24 weeks. These results indicate that CHL can inhibit both tumor promotion and the progression of papillomagenesis in the two-stage mouse skin carcinogenesis induced by DMBA and TPA.


Asunto(s)
9,10-Dimetil-1,2-benzantraceno/antagonistas & inhibidores , Anticarcinógenos/uso terapéutico , Antimutagênicos/uso terapéutico , Clorofilidas/uso terapéutico , Neoplasias Cutáneas/prevención & control , Animales , Quimioprevención , Femenino , Masculino , Ratones , Ratones Endogámicos ICR , Ratas , Ratas Sprague-Dawley , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Acetato de Tetradecanoilforbol/toxicidad
19.
Biochem Pharmacol ; 62(8): 1013-23, 2001 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-11597570

RESUMEN

cis-platinum(II) (cis-diammine dichloroplatinum; cisplatin) is a potent antitumor compound that is widely used for the treatment of many malignancies. An important side-effect of cisplatin is nephrotoxicity, which results from injury to renal tubular epithelial cells and can be manifested as either acute renal failure or a chronic syndrome characterized by renal electrolyte wasting. Recently, apoptosis has been recognized as an important mechanism of cell death mediating the antitumor effect of cisplatin. This study was undertaken to examine the mechanisms of cell death induced by cisplatin in M-1 cells, which were derived from the outer cortical collecting duct cells of SV40 transgenic mice. Treatment of M-1 cells with high concentrations of cisplatin (0.5 and 1 mM) for 2 hr led to necrotic cell death, whereas a 24-hr treatment with 5-20 microM cisplatin led to apoptosis. Antioxidants protected against cisplatin-induced necrosis, but not apoptosis, indicating that reactive oxygen species play a role in mediating necrosis but not apoptosis induced by cisplatin and that the mechanism of cell death induced by cisplatin is concentration dependent. The low concentrations of cisplatin, which induced apoptosis in M-1 cells, did not affect the expression levels of Bcl-2-related proteins and did not activate c-Jun NH2-terminal kinase (SAPK/JNK). Cisplatin induced the translocation of endogenous Bax from the cytosolic to the membrane fractions and, subsequently, the release of cytochrome c. Overexpression of Bcl-2 blocked cisplatin-induced apoptosis and Bax translocation. These observations suggest that the subcellular redistribution of Bax is a critical event in the apoptosis induced by cisplatin.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis , Cisplatino/farmacología , Túbulos Renales Colectores/efectos de los fármacos , Proteínas Proto-Oncogénicas/metabolismo , Animales , Antioxidantes/farmacología , Transporte Biológico , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Grupo Citocromo c/metabolismo , Citosol/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos , Túbulos Renales Colectores/citología , Túbulos Renales Colectores/metabolismo , Ratones , Mitocondrias/metabolismo , Proteínas Quinasas Activadas por Mitógenos/fisiología , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Proteína X Asociada a bcl-2
20.
J Biochem ; 116(5): 1139-45, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7896744

RESUMEN

Twenty-two mutants between beta Glu-161 and beta Lys-201 of Escherichia coli H(+)-ATPase beta subunit could grow by oxidative phosphorylation, but 11 other such mutants, beta Glu-181-->Gln, Asp, Asn, Thr, Ser, Ala, or Lys and beta Arg-182-->Lys, Ala, Glu, or Gln, could not. The beta Asp-181, beta Lys-182, and other defective mutants had 1.4, 1, and < 0.1%, respectively, of the wild-type membrane ATPase activity. Partially purified F1-ATPases from all mutants at positions 181 and 182, except for the beta Asp-181 and beta Lys-182 mutants, showed very low unisite catalysis. Purified F1-ATPases of the beta Gln-181 and beta Ala-181 mutants showed no multisite (or steady state) catalysis and slow unisite catalysis (< or = 1% of that of the wild type): their defects could be attributed to decreased catalytic rates (low k+2 and k-2). Changes of the k+2 and k-2 values in the beta Asp-181 enzyme, which showed detectable multi- and unisite catalysis, were less marked (27 and 21%, respectively, of wild-type rates). The beta Gln-182 enzyme showed defective catalysis (< or = 0.1% of the multi- and approximately 1% of the unisite catalyses of the wild type), whereas the beta Lys-182 enzyme showed 1 and 85% of the wild-type multisite and unisite catalytic rates, respectively. beta Lys-182 had wild-type values of k+2 and k-2, but beta Gln-182 had k+2 about 10-fold lower than that of wild type.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Arginina/química , Ácido Glutámico/química , ATPasas de Translocación de Protón/química , Nucleótidos de Adenina , Secuencia de Bases , Sitios de Unión , Cinética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida
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