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1.
Ann Surg Oncol ; 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39073661

RESUMEN

BACKGROUND: The selection of hyperthermic intraperitoneal chemotherapy (HIPEC) or early postoperative intraperitoneal chemotherapy (EPIC) for peritoneal metastases from colorectal cancer or appendiceal neoplasms following cytoreductive surgery (CRS) depends on the surgeon's discretion. This study was designed to compare postoperative and oncologic outcomes of HIPEC and EPIC using inverse probability of treatment weighting (IPTW). METHODS: This study included 175 patients who received HIPEC or EPIC following CRS at a single tertiary university hospital between December 1999 and December 2020. Inverse probability of treatment weighting analysis was performed to control for pretreatment characteristics between the two groups. Multivariate analysis was performed to determine factors associated with postoperative and survival outcomes. RESULTS: After IPTW, no significant differences in baseline demographics and tumor characteristics were observed between the two groups. The HIPEC group had a significantly longer operation time than the EPIC group. The EPIC group showed a significantly higher postoperative mortality rate than the HIPEC group. Operation time (odds ratio [OR] 1.01; 95% confidence interval [CI] 1.01-1.02; p < 0.001), bowel anastomosis (OR 7.25; 95% CI 1.16-45.2; p = 0.034), neoadjuvant chemotherapy (OR 7.62; 95% CI 1.85-31.4; p = 0.005), and EPIC (OR 8.76; 95% CI 2.16-35.5; p = 0.002) were independent risk factors for major surgical complications. No association was observed between intraperitoneal chemotherapy type and major hematologic toxicity, overall survival, progression-free survival, or peritoneal progression-free survival. CONCLUSIONS: EPIC was a risk factor for major surgical complications. Survival outcomes were similar between the two types of intraperitoneal chemotherapy.

2.
Int J Mol Sci ; 24(21)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37958616

RESUMEN

Breast cancer is a common type of cancer characterized by high mortality rates. However, chemotherapy is not selective and often leads to side-effects. Therefore, there is a need for the development of highly efficient drugs. Recent studies have shown that some extracellular vesicles (EVs) derived from cell cultures possess anti-cancer activity and hold great potential as cancer therapeutics. However, the use of mammalian cell cultures for EV production results in low productivity and high costs. To address this issue, extracellular vesicles derived from perilla leaves (Perex) were isolated and investigated for their anti-cancer activity in various cancer cells. Initially, a high concentration of Perex with a low level of impurities was successfully purified through a combination of ultrafiltration and size-exclusion chromatography. Perex exhibited potent anti-cancer activities, inhibiting the proliferation, migration, and invasion of MDA-MB-231 cancer cells, which have high levels of caveolin-1 compared to other cancer and normal cells. This selective attack on cancer cells with high levels of caveolin-1 reduces unwanted side-effects on normal cells. Considering its high productivity, low production cost, selective anti-cancer activity, and minimal side-effects, Perex represents a promising candidate for the therapeutic treatment of breast cancer.


Asunto(s)
Neoplasias de la Mama , Vesículas Extracelulares , Animales , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Caveolina 1/metabolismo , Vesículas Extracelulares/metabolismo , Técnicas de Cultivo de Célula , Proliferación Celular , Línea Celular Tumoral , Mamíferos/metabolismo
3.
J Am Chem Soc ; 144(31): 14132-14139, 2022 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-35905443

RESUMEN

Proton translocation through the membrane-embedded Fo component of F-type ATP synthase (FoF1) is facilitated by the rotation of the Fo c-subunit ring (c-ring), carrying protons at essential acidic amino acid residues. Cryo-electron microscopy (Cryo-EM) structures of FoF1 suggest a unique proton translocation mechanism. To elucidate it based on the chemical conformation of the essential acidic residues of the c-ring in FoF1, we determined the structure of the isolated thermophilic Bacillus Fo (tFo) c-ring, consisting of 10 subunits, in membranes by solid-state NMR. This structure contains a distinct proton-locking conformation, wherein Asn23 (cN23) CγO and Glu56 (cE56) CδOH form a hydrogen bond in a closed form. We introduced stereo-array-isotope-labeled (SAIL) Glu and Asn into the tFoc-ring to clarify the chemical conformation of these residues in tFoF1-ATP synthase (tFoF1). Two well-separated 13C signals could be detected for cN23 and cE56 in a 505 kDa membrane protein complex, respectively, thereby suggesting the presence of two distinct chemical conformations. Based on the signal intensity and structure of the tFoc-ring and tFoF1, six pairs of cN23 and cE56 surrounded by membrane lipids take the closed form, whereas the other four in the a-c interface employ the deprotonated open form at a proportion of 87%. This indicates that the a-c interface is highly hydrophilic. The pKa values of the four cE56 residues in the a-c interface were estimated from the cN23 signal intensity in the open and closed forms and distribution of polar residues around each cE56. The results favor a rotation of the c-ring for ATP synthesis.


Asunto(s)
Bacillus , Adenosina Trifosfato/metabolismo , Bacillus/metabolismo , Microscopía por Crioelectrón , Ácido Glutámico , Conformación Proteica , Subunidades de Proteína/química , ATPasas de Translocación de Protón/metabolismo , Protones
4.
Biochem Biophys Res Commun ; 616: 19-25, 2022 08 06.
Artículo en Inglés | MEDLINE | ID: mdl-35636251

RESUMEN

Toxin - Antitoxin systems are crucial for bacterial survival against harsh circumstances such as antibiotic treatment. The VapBC systems are the most abundant Toxin-Antitoxin systems among the Toxin - Antitoxin systems in the Mycobacterium tuberculosis. The VapBC43 system is one of them, which is related to the response to the vancomycin treatment. However, the structure of the VapBC43 complex remained unknown. Here, we present the crystal structure of the VapBC43 complex in which a single VapB43 molecule binds to the VapC43 dimer. The electrophoretic mobility shift assay shows that the VapB43 can bind to its promoter DNA. In addition, this structure reveals that the VapC43 contains a PIN (PilT N-terminus) domain motif which is essential for ribonuclease activity but has less conserved acidic residues than other homologs. The results of ribonuclease assays show that the VapC43 exhibits ribonuclease activity despite the lack of acidic residues which are well conserved in a PIN domain superfamily. Based on the previous finding that the VapBC43 contributes to the survival of Mycobacterium tuberculosis under vancomycin treatment, the structural information of the VapBC43 complex may enable the development of the inhibitor of VapC43 that can be used as an adjuvant for vancomycin therapy against M. tuberculosis.


Asunto(s)
Antitoxinas , Toxinas Bacterianas , Mycobacterium tuberculosis , Antitoxinas/química , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/química , Modelos Moleculares , Mycobacterium tuberculosis/metabolismo , Ribonucleasas/química , Vancomicina
5.
Int J Mol Sci ; 23(13)2022 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-35806139

RESUMEN

Prostate cancer (PCa) is the most commonly diagnosed malignancy among men in developed countries. The five-year survival rate for men diagnosed with early-stage PCa is approximately 100%, while it is less than 30% for castration-resistant PCa (CRPC). Currently, the detection of prostate-specific antigens as biomarkers for the prognosis of CRPC is criticized because of its low accuracy, high invasiveness, and high false-positive rate. Therefore, it is important to identify new biomarkers for prediction of CRPC progression. Extracellular vesicles (EVs) derived from tumors have been highlighted as potential markers for cancer diagnosis and prognosis. Specifically, urinary EVs directly reflect changes in the pathophysiological conditions of the urogenital system because it is exposed to prostatic secretions. Thus, detecting biomarkers in urinary EVs provides a promising approach for performing an accurate and non-invasive liquid biopsy for CPRC. In this study, we effectively isolated urinary EVs with low protein impurities using size-exclusion chromatography combined with ultrafiltration. After EV isolation and characterization, we evaluated the miRNAs in urinary EVs from healthy donors and patients with CRPC. The results indicated that miRNAs (miR-21-5p, miR-574-3p, and miR-6880-5p) could be used as potential biomarkers for the prognosis of CRPC. This analysis of urinary EVs contributes to the fast and convenient prognosis of diseases, including CRPC, in the clinical setting.


Asunto(s)
Vesículas Extracelulares , MicroARNs , Neoplasias de la Próstata Resistentes a la Castración , Biomarcadores de Tumor/metabolismo , Vesículas Extracelulares/metabolismo , Humanos , Biopsia Líquida , Masculino , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias de la Próstata Resistentes a la Castración/patología
6.
Vox Sang ; 115(3): 233-240, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31877575

RESUMEN

BACKGROUND AND OBJECTIVES: ABO isoagglutinin titre is important for evaluating and monitoring ABO-incompatible (ABOi) stem cells or solid organ transplantations. There are several methods to measure the titre level, including the tube haemagglutination method, micro-column agglutination and erythrocyte-magnetized technology (EMT). However, few studies have reported isoagglutinin measured by EMT. Here, we compared the isoagglutinin titre of normal individuals obtained by an automated instrument with that obtained by conventional manual methods to evaluate the feasibility of replacing the manual method with the automated instrument. MATERIALS AND METHODS: The ABO isoagglutinin titre was measured on residual samples of healthy individuals who visited the health promotion centre of the National Cancer Center, Korea, from April to October 2015. Samples from 120 patients were collected, which included 20 males and 20 females for each blood group (A, B and O). IgM and IgG ABO isoagglutinin titres of each blood group were measured by the tube haemagglutination, micro-column agglutination and EMT techniques. The median (minimum-maximum) titres were compared, and the concordance between two methods was evaluated with the rate of results showing within one titre difference. RESULTS: The median ABO IgM and IgG titres of all blood groups obtained by the EMT method were higher than that obtained by the conventional tube haemagglutination and micro-column agglutination. CONCLUSION: The agreement between the two methods was comparable in case of IgM but low in IgG.


Asunto(s)
Sistema del Grupo Sanguíneo ABO/sangre , Hemaglutinación , Pruebas Inmunológicas/métodos , Femenino , Pruebas de Hemaglutinación/métodos , Humanos , Masculino , República de Corea
9.
Int J Mol Sci ; 20(2)2019 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-30646576

RESUMEN

Autophagy is a natural physiological process, and it induces the lysosomal degradation of intracellular components in response to environmental stresses, including nutrient starvation. Although an adequate autophagy level helps in cell survival, excessive autophagy triggered by stress such as starvation leads to autophagy-mediated apoptosis. Chinese hamster ovary (CHO) cells are widely used for producing biopharmaceuticals, including monoclonal antibodies. However, apoptosis induced by high stress levels, including nutrient deficiency, is a major problem in cell cultures grown in bioreactors, which should be overcome. Therefore, it is necessary to develop a method for suppressing excessive autophagy and for maintaining an appropriate autophagy level in cells. Therefore, we investigated the effect of silkworm storage protein 1 (SP1), an antiapoptotic protein, on autophagy-mediated apoptosis. SP1-expressing CHO cells were generated to assess the effect and molecular mechanism of SP1 in suppressing autophagy. These cells were cultured under starvation conditions by treatment with Earle's balanced salt solution (EBSS) to induce autophagy. We observed that SP1 significantly inhibited autophagy-mediated apoptosis by suppressing caspase-3 activation and reactive oxygen species generation. In addition, SP1 suppressed EBSS-induced conversion of LC3-I to LC3-II and the expression of autophagy-related protein 7. Notably, basal Beclin-1 level was significantly low in the SP1-expressing cells, indicating that SP1 regulated upstream events in the autophagy pathway. Together, these findings suggest that SP1 offers a new strategy for overcoming severe autophagy-mediated apoptosis in mammalian cells, and it can be used widely in biopharmaceutical production.


Asunto(s)
Apoptosis/genética , Autofagia/genética , Proteínas de Insectos/genética , Animales , Beclina-1/genética , Bombyx/genética , Células CHO , Supervivencia Celular/genética , Cricetulus , Regulación de la Expresión Génica/genética , Humanos
10.
J Biomol NMR ; 70(1): 53-65, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29197977

RESUMEN

FoF1-ATP synthase catalyzes ATP hydrolysis/synthesis coupled with a transmembrane H+ translocation in membranes. The Fo c-subunit ring plays a major role in this reaction. We have developed an assignment strategy for solid-state 13C NMR (ssNMR) signals of the Fo c-subunit ring of thermophilic Bacillus PS3 (TFo c-ring, 72 residues), carrying one of the basic folds of membrane proteins. In a ssNMR spectrum of uniformly 13C-labeled sample, the signal overlap has been a major bottleneck because most amino acid residues are hydrophobic. To overcome signal overlapping, we developed a method designated as COmplementary Sequential assignment with MInimum Labeling Ensemble (COSMILE). According to this method, we generated three kinds of reverse-labeled samples to suppress signal overlapping. To assign the carbon signals sequentially, two-dimensional Cα(i+1)-C'Cα(i) correlation and dipolar assisted rotational resonance (DARR) experiments were performed under magic-angle sample spinning. On the basis of inter- and intra-residue 13C-13C chemical shift correlations, 97% of Cα, 97% of Cß and 92% of C' signals were assigned directly from the spectra. Secondary structure analysis predicted a hairpin fold of two helices with a central loop. The effects of saturated and unsaturated phosphatidylcholines on TFo c-ring structure were examined. The DARR spectra at 15 ms mixing time are essentially similar to each other in saturated and unsaturated lipid membranes, suggesting that TFo c-rings have similar structures under the different environments. The spectrum of the sample in saturated lipid membranes showed better resolution and structural stability in the gel state. The C-terminal helix was suggested to locate in the outer layer of the c-ring.


Asunto(s)
Resonancia Magnética Nuclear Biomolecular/métodos , ATPasas de Translocación de Protón/química , Bacillus/química , Isótopos de Carbono , Lípidos de la Membrana/química , Fosfatidilcolinas/química , Subunidades de Proteína
11.
Biochim Biophys Acta Proteins Proteom ; 1865(1): 65-75, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27784646

RESUMEN

Translation initiation, the rate-limiting step in the protein synthesis, is tightly regulated. As one of the translation initiation factors, translation initiation factor 1 (IF1) plays crucial roles not only in translation but also in many cellular processes that are important for genomic stability, such as the activity of RNA chaperones. Here, we characterize the RNA interactions and dynamics of IF1 from Staphylococcus aureus Mu50 (IF1Sa) by NMR spectroscopy. First, the NMR-derived solution structure of IF1Sa revealed that IF1Sa adopts an oligonucleotide/oligosaccharide binding (OB)-fold. Structural comparisons showed large deviations in the α-helix and the following loop, which are potential RNA-binding regions of the OB-fold, as well as differences in the electrostatic potential surface among bacterial IF1s. Second, the 15N NMR relaxation data for IF1Sa indicated the flexible nature of the α-helix and the following loop region of IF1Sa. Third, RNA-binding properties were studied using FP assays and NMR titrations. FP binding assays revealed that IF1Sa binds to RNAs with moderate affinity. In combination with the structural analysis, the NMR titration results revealed the RNA binding sites. Taken together, these results show that IF1Sa binds RNAs with moderate binding affinity via the residues that occupy the large surface area of its ß-barrel. These findings suggest that IF1Sa is likely to bind RNA in various conformations rather than only at a specific site and indicate that the flexible RNA binding mode of IF1Sa is necessary for its interaction with various RNA substrates.


Asunto(s)
Proteínas Bacterianas/química , Factores Procarióticos de Iniciación/química , Proteínas de Unión al ARN/química , Staphylococcus aureus/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/ultraestructura , Sitios de Unión , Espectroscopía de Resonancia Magnética , Resonancia Magnética Nuclear Biomolecular , Iniciación de la Cadena Peptídica Traduccional , Factores Procarióticos de Iniciación/genética , Factores Procarióticos de Iniciación/ultraestructura , Unión Proteica , Estructura Secundaria de Proteína , ARN Bacteriano/química , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/ultraestructura , Alineación de Secuencia , Staphylococcus aureus/genética
12.
Molecules ; 21(4): 527, 2016 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-27110759

RESUMEN

The aim of this study was to observe whether Polycal has inhibitory activity on ligation-induced experimental periodontitis and related alveolar bone loss in rats following topical application to the gingival regions. One day after the ligation placements, Polycal (50, 25, and 12.5 mg/mL solutions at 200 µL/rat) was topically applied to the ligated gingival regions daily for 10 days. Changes in bodyweight, alveolar bone loss index, and total number of buccal gingival aerobic bacterial cells were monitored, and the anti-inflammatory effects were investigated via myeloperoxidase activity and levels of the pro-inflammatory cytokines IL-1ß and TNF-α. The activities of inducible nitric oxide synthase (iNOS) and lipid peroxidation (MDA) were also evaluated. Bacterial proliferation, periodontitis, and alveolar bone loss induced by ligature placements were significantly inhibited after 10 days of continuous topical application of Polycal. These results indicate that topical application of Polycal has a significant inhibitory effect on periodontitis and related alveolar bone loss in rats mediated by antibacterial, anti-inflammatory, and anti-oxidative activities.


Asunto(s)
Pérdida de Hueso Alveolar/prevención & control , Antiinfecciosos/administración & dosificación , Antiinflamatorios/administración & dosificación , Antioxidantes/administración & dosificación , Gluconato de Calcio/administración & dosificación , Periodontitis/tratamiento farmacológico , beta-Glucanos/administración & dosificación , Administración Tópica , Pérdida de Hueso Alveolar/metabolismo , Animales , Antiinfecciosos/farmacología , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Bacterias/efectos de los fármacos , Gluconato de Calcio/farmacología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Combinación de Medicamentos , Humanos , Interleucina-1beta/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Masculino , Estrés Oxidativo/efectos de los fármacos , Periodontitis/metabolismo , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/metabolismo , beta-Glucanos/farmacología
13.
Int J Mol Sci ; 16(10): 24219-42, 2015 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-26473849

RESUMEN

Plants rich in antioxidant substances may be useful for preventing skin aging. Pomegranates, containing flavonoids and other polyphenolic compounds, are widely consumed due to their beneficial properties. We examined the underlying mechanisms of dried pomegranate concentrate powder (PCP) on melanin synthesis in B16F10 melanoma cells. The antioxidant effects of PCP were determined by measuring free radical scavenging capacity and transcript levels of antioxidant enzymes. To explore the inhibitory effects of PCP on melanin synthesis, we measured tyrosinase activity and melanin content in α-melanocyte stimulating hormone (α-MSH)-stimulated B16F10 cells. In addition, the levels of tyrosinase-related protein-1 (TRP-1), TRP-2, tyrosinase, and microphthalmia-associated transcription factor (MITF) expression were determined by Western blotting. Changes in the phosphorylation status of protein kinase A (PKA), cAMP response element-binding protein (CREB), mitogen-activated protein kinases (MAPKs), phosphatidylinositol 3-kinase (PI3K), serine/threonine kinase Akt, and glycogen kinase 3ß (GSK3ß) were also examined. The free radical scavenging activity of PCP increased in a dose-dependent manner. In PCP-treated B16F10 cells, transcript levels of glutathione peroxidase-1 (GPx-1) were increased compared with α-MSH-stimulated cells. In addition, PCP led to the down-regulation of phospho-p38, phospho-PKA, phospho-CREB, phospho-GSK3ß, MITF, and TRP-1 compared with α-MSH-stimulated B16F10 cells. We believe this effect may be associated with PCP activity, which leads to the inhibition of melanin production and tyrosinase activity. These results suggest that PCP decreases tyrosinase activity and melanin production via inactivation of the p38 and PKA signaling pathways, and subsequently decreases phosphorylation of CREB, MITF, and melanogenic enzymes. These observations provided new insights on the molecular mechanisms of the skin-whitening property of PCP.


Asunto(s)
Lythraceae/metabolismo , Melaninas/biosíntesis , Melanoma Experimental/tratamiento farmacológico , Monofenol Monooxigenasa/metabolismo , Preparaciones de Plantas/farmacología , Animales , Antioxidantes/farmacología , Proteína de Unión a CREB/metabolismo , Línea Celular Tumoral , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Depuradores de Radicales Libres/farmacología , Liofilización , Glutatión Peroxidasa/metabolismo , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Ratones , Factor de Transcripción Asociado a Microftalmía/metabolismo , Fosfatidilinositol 3-Quinasa/metabolismo , Fosforilación/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , alfa-MSH/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Glutatión Peroxidasa GPX1
14.
J Cosmet Sci ; 66(3): 145-59, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26454903

RESUMEN

Synopsis Botanical antioxidants have attracted much attention as useful preventatives of skin damage. Pomegranate is consumed throughout the world for its beneficial health effects, including its antioxidant and anti-inflammatory activities. We investigated whether pomegranate concentrated solution (PCS) could serve as a potential functional cosmetic ingredient that exerts a skin-whitening effect and antiwrinkle activity. To investigate the moisturizing effect of PCS, hyaluronidase activity was examined in human keratinocytes (HaCaT). Elastase and procollagenase activities were assessed in normal human primary dermal fibroblast-neonatal (HDF-N) cells to determine their antiwrinkle effects. Metalloproteinase 1 (MMP-1) activity was also assessed following ultraviolet A (UVA) irradiation. Whitening effects were measured by a tyrosinase inhibition assay and melanin formation test in mouse melanocytes (Melan-a). In addition, histopathological analysis was performed to determine the number of microfolds formed on the epithelial surface, mean epithelial thickness, mean number of inflammatory cells infiltrating the dermis, and collagen fiber-occupied regions within the dermis. Hyaluronan synthesis was significantly increased by PCS in HaCaT cells, while procollagenase and elastase activities were decreased in HDF-N cells. A significant decrease in UVA-induced MMP-1 activity was also observed in PCS-treated HDF-N cells, compared with UVA-exposed cells. PCS effectively reduced melanin production and mushroom tyrosinase activity in Melan-a cells. Moreover, UVB-induced histopathological dermal sclerosis and inflammatory signs were significantly attenuated in PCS-administered mice compared with UVB-exposed mice. Conclusions: Our results suggest that PCS prevents signs of aging, including those related to photoaging. These effects are associated with enhanced hyaluronan synthesis, as well as suppressed elastase, collagenase, MMP-1, and tyrosinase activities and melanin production. UVB-induced photoaging, such as histopathological dermal sclerosis and inflammatory signs, were effectively reduced on the addition of PCS. These results also suggest that skin aging can be prevented and reduced by the antioxidant effects of PCS.


Asunto(s)
Hialuronoglucosaminidasa/metabolismo , Lythraceae , Metaloproteasas/metabolismo , Monofenol Monooxigenasa/metabolismo , Línea Celular , Humanos , Piel/citología , Piel/enzimología , Envejecimiento de la Piel , Preparaciones para Aclaramiento de la Piel , Soluciones
15.
Biophys J ; 106(2): 390-8, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24461014

RESUMEN

FoF1-ATP synthase uses the electrochemical potential across membranes or ATP hydrolysis to rotate the Foc-subunit ring. To elucidate the underlying mechanism, we carried out a structural analysis focused on the active site of the thermophilic c-subunit (TFoc) ring in membranes with a solid-state NMR method developed for this purpose. We used stereo-array isotope labeling (SAIL) with a cell-free system to highlight the target. TFoc oligomers were purified using a virtual ring His tag. The membrane-reconstituted TFoc oligomer was confirmed to be a ring indistinguishable from that expressed in E. coli on the basis of the H(+)-translocation activity and high-speed atomic force microscopic images. For the analysis of the active site, 2D (13)C-(13)C correlation spectra of TFoc rings labeled with SAIL-Glu and -Asn were recorded. Complete signal assignment could be performed with the aid of the C(α)i+1-C(α)i correlation spectrum of specifically (13)C,(15)N-labeled TFoc rings. The C(δ) chemical shift of Glu-56, which is essential for H(+) translocation, and related crosspeaks revealed that its carboxyl group is protonated in the membrane, forming the H(+)-locked conformation with Asn-23. The chemical shift of Asp-61 C(γ) of the E. coli c ring indicated an involvement of a water molecule in the H(+) locking, in contrast to the involvement of Asn-23 in the TFoc ring, suggesting two different means of proton storage in the c rings.


Asunto(s)
Dominio Catalítico , Membrana Celular/enzimología , Subunidades de Proteína/química , ATPasas de Translocación de Protón/química , Temperatura , Secuencia de Aminoácidos , Membrana Celular/metabolismo , Membrana Dobles de Lípidos/metabolismo , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Datos de Secuencia Molecular , Multimerización de Proteína , Estructura Cuaternaria de Proteína , Subunidades de Proteína/metabolismo , ATPasas de Translocación de Protón/metabolismo
16.
J Cosmet Sci ; 65(5): 285-98, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25682620

RESUMEN

BACKGROUND: There have been many attempts to search for affordable and effective functional cosmetic ingredients, especially from natural sources. OBJECTIVES: As research into developing a functional cosmetic ingredient, we investigated whether exopolymers from Aureobasidium pullulans SM2001 (E-AP-SM2001) exert antioxidant, antiwrinkle, whitening, and skin moisturizing effects. METHODS: Antioxidant effects of E-AP-SM2001 were determined by measuring free radical scavenging capacity and superoxide dismutase (SOD)-like activity. Antiwrinkle effects were assessed through the inhibition of hyaluronidase, elastase, collagenase, and matrix metalloproteinase (MMP)-1. Whitening effects were measured by tyrosinase inhibition assay, and by melanin formation test in B16/F10 melanoma cells. Skin moisturizing effects were detected by mouse skin water content test. RESULTS: E-AP-SM2001 showed potent DPPH radical scavenging activity and SOD-like effects. Additionally, hyaluronidase, elastase, collagenase, and MMP-1 activities were significantly inhibited by E-AP-SM2001. We also observed that E-AP-SM2001 effectively reduced melanin production by B16/F10 melanoma cells and mushroom tyrosinase activities. Furthermore, significant increases in skin water content were detected in E-AP-SM2001- treated mouse skin, as compared with vehicle-treated control skin. Notably, a mask pack containing E-AP-SM2001 showed a >twofold more extensive moisturizing effect compared with one containing Saccharomycopsis ferment filtrate. CONCLUSIONS: Our results suggest that E-AP-SM2001 has adequate antiaging, antiwrinkle, and whitening benefits and skin moisturizing effect. These effects involve reducing hyaluronidase, elastase, collagenase, and MMP-1 activities, as well as inhibition of melanin production and tyrosinase activities. Therefore, the antioxidant E-AP-SM2001 may serve as a predictable functional ingredient.


Asunto(s)
Ascomicetos/química , Polímeros/farmacología , Envejecimiento de la Piel/efectos de los fármacos , Animales , Antioxidantes/farmacología , Línea Celular Tumoral , Humanos , Ratones
17.
Biophys Chem ; 309: 107228, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38552402

RESUMEN

ß-lactam antibiotics are the most successful and commonly used antibacterial agents, but the emergence of resistance to these drugs has become a global health threat. The expression of ß-lactamase enzymes produced by pathogens, which hydrolyze the amide bond of the ß-lactam ring, is the major mechanism for bacterial resistance to ß-lactams. In particular, among class A, B, C and D ß-lactamases, metallo-ß-lactamases (MBLs, class B ß-lactamases) are considered crucial contributors to resistance in gram-negative bacteria. To combat ß-lactamase-mediated resistance, great efforts have been made to develop ß-lactamase inhibitors that restore the activity of ß-lactams. Some ß-lactamase inhibitors, such as diazabicyclooctanes (DBOs) and boronic acid derivatives, have also been approved by the FDA. Inhibitors used in the clinic can inactivate mostly serine-ß-lactamases (SBLs, class A, C, and D ß-lactamases) but have not been effective against MBLs until now. In order to develop new inhibitors particularly for MBLs, various attempts have been suggested. Based on structural and mechanical studies of MBL enzymes, several MBL inhibitor candidates, including taniborbactam in phase 3 and xeruborbactam in phase 1, have been introduced in recent years. However, designing potent inhibitors that are effective against all subclasses of MBLs is still extremely challenging. This review summarizes not only the types of ß-lactamase and mechanisms by which ß-lactam antibiotics are inactivated, but also the research finding on ß-lactamase inhibitors targeting these enzymes. These detailed information on ß-lactamases and their inhibitors could give valuable information for novel ß-lactamase inhibitors design.


Asunto(s)
Antibacterianos , Inhibidores de beta-Lactamasas , Inhibidores de beta-Lactamasas/farmacología , Inhibidores de beta-Lactamasas/química , Inhibidores de beta-Lactamasas/uso terapéutico , Antibacterianos/farmacología , Antibacterianos/química , beta-Lactamas/metabolismo , beta-Lactamas/farmacología , beta-Lactamasas , Farmacorresistencia Microbiana
18.
Molecules ; 18(11): 13410-24, 2013 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-24177697

RESUMEN

Due to the widespread and increasing appearance of antibiotic resistance, a new strategy is needed for developing novel antibiotics. Especially, there are no specific antibiotics for Helicobacter pylori (H. pylori). H. pylori are bacteria that live in the stomach and are related to many serious gastric problems such as peptic ulcers, chronic gastritis, mucosa-associated lymphoid tissue lymphoma, and gastric cancer. Because of its importance as a human pathogen, it's worth studying the structure and function of the proteins from H. pylori. After the sequencing of the H. pylori strain 26695 in 1997, more than 1,600 genes were identified from H. pylori. Until now, the structures of 334 proteins from H. pylori have been determined. Among them, 309 structures were determined by X-ray crystallography and 25 structures by Nuclear Magnetic Resonance (NMR), respectively. Overall, the structures of large proteins were determined by X-ray crystallography and those of small proteins by NMR. In our lab, we have studied the structural and functional characteristics of small proteins from H. pylori. In this review, 25 NMR structures of H. pylori proteins will be introduced and their structure-function relationships will be discussed.


Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/química , Helicobacter pylori/metabolismo , Espectroscopía de Resonancia Magnética/métodos , Descubrimiento de Drogas , Helicobacter pylori/efectos de los fármacos
19.
Health Secur ; 21(2): 95-104, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36888540

RESUMEN

New and reemerging infectious disease outbreaks threaten human safety worldwide, increasing the urgency to implement biosurveillance systems that enhance government capacity in public health emergency preparedness and response. To do so, it is necessary to evaluate existing surveillance and response activities and identify potential barriers at the national level. This study aimed to assess the current status and readiness of government agencies in South Korea, particularly for information sharing and use, and to identify barriers and opportunities in developing an agency-integrated biosurveillance system. The target sample size was 66 government officials, working at 6 relevant government ministries. We invited a total of 100 officials to participate. A total of 34 government officials completed the survey (34.0% response rate), 18 (52.9%) of whom were affiliated with the Korea Disease Control and Prevention Agency or the Ministry of Health and Welfare. Findings revealed that information sharing between government agencies occurred frequently, but a discrepancy existed in terms of the type of information shared and stored. Although information sharing with other agencies and ministries occurred at all stages-prevention, preparation, response, and recovery-it mostly revolved around preventive activities, with no respondents reportedly sharing recovery-related information. An agency-integrated biosurveillance system is crucial in preparing for the next pandemic, as well as supporting information sharing, analysis, and interpretation across humans, animals, and the environment. It is key to national and global health security.


Asunto(s)
Biovigilancia , Animales , Humanos , Evaluación de Necesidades , Brotes de Enfermedades/prevención & control , Gobierno Federal , República de Corea
20.
J Prev Med Public Health ; 56(1): 67-76, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36746424

RESUMEN

OBJECTIVES: Previous studies have reported that people with disabilities are more likely to be impoverished and affected by excessive medical costs than people without disabilities. Public transfer income (PTI) reduces financial strain in low-income households. This study examined the impact of PTI on catastrophic health expenditures (CHE), focusing on low-income households and households with Medical Aid beneficiaries that contained people with disabilities. METHODS: We constructed a panel dataset by extracting data on registered households with disabilities from the Korea Welfare Panel Study 2012-2019. We then used a generalized estimating equation model to estimate the impacts of PTI on CHE. A subgroup analysis was carried out to assess the moderating effects of family income levels and health insurance types. RESULTS: As PTI increased, the odds ratio (OR) of CHE in households that contained people with disabilities decreased significantly (OR, 0.92; 95% confidence interval [CI], 0.89 to 0.94; p<0.001). In particular, PTI effectively reduced the likelihood of CHE for low-income households (OR, 0.85; 95% CI, 0.81 to 0.89; p<0.001) and those who received medical benefits (OR, 0.78; 95% CI, 0.68 to 0.89; p<0.001). CONCLUSIONS: This study highlights the positive effect of PTI on decreasing CHE. Household income and the health insurance type were significant effect modifiers, but economic barriers seemed to persist among low-income households with non-Medical Aid beneficiaries. Federal policies or programs should consider increasing the total amount of PTI targeting low-income households with disabilities that are not covered by the Medical Aid program.


Asunto(s)
Personas con Discapacidad , Gastos en Salud , Humanos , Enfermedad Catastrófica , Pobreza , República de Corea
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