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AIMS: Cell adhesion molecule 1 (CADM1) is a member of the immunoglobulin superfamily and is abundantly expressed on nerve fibers. Recently, the anti-CADM1 ectodomain antibody 3E1 has proven useful as a drug delivery vector for CADM1-expressing cells in vitro. When injected subcutaneously into mice, whether 3E1 accumulates on nerve fibers and serves as an analgesic was examined. MAIN METHODS: Injected 3E1 was detected by immunohistochemistry and double immunofluorescence. Analgesic effects were verified by a formalin-induced chemical-inflammatory pain test and video-recorded behavior analysis that were performed 6, 12, and 24â¯h after antibody injection. Primary cultures of mouse dorsal root ganglion (DRG) cells were incubated with 3E1 and expressions of CADM1 and its key downstream molecules were examined by Western blot analyses and live cell imaging. DRG cells were loaded with a Ca2+ fluorescent indicator Fluo-8 and a femtosecond laser pulse was irradiated near the cell body to mechanically stimulate the nerves. KEY FINDINGS: Subcutaneously injected 3E1 was widely localized almost exclusively on peripheral nerve fibers in the dermis. In formalin tests, 3E1-injected mice exhibited less pain-related behavior than control mice. When 3E1 was added to DRG cell cultures, it localized to neurites and resulted in decreased expression of CADM1, increased phosphorylation of Src and Akt, and CADM1-3E1 complex formation. Femtosecond laser-induced stimulation transmission along neurites was clearly visualized by Fluo-8 fluorescence in control cells, whereas it was markedly suppressed in 3E1-treated cells. SIGNIFICANCE: 3E1 was suggested to be a potential long-acting analgesic based on its high affinity for CADM1.
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Cell adhesion molecule 1 (CADM1), a single-pass transmembrane protein, is involved in oncogenesis. We previously demonstrated the therapeutic efficacy of anti-CADM1 ectodomain monoclonal antibodies against mesothelioma; however, the underlying mechanism is unclear. In the present study, we explored the molecular behavior of anti-CADM1 antibodies in CADM1-expressing tumor cells. Sequencing analyses revealed that the anti-CADM1 chicken monoclonal antibodies 3E1 and 9D2 are IgY and IgM isotype antibodies, respectively. Co-administration of 3E1 and 9D2 altered the subcellular distribution of CADM1 from the detergent-soluble fraction to the detergent-resistant fraction in tumor cells. Using recombinant chicken-mouse chimeric antibodies that had been isotype-switched from IgG to IgM, we demonstrated that the combination of the variable region of 3E1 and the constant region of IgM was required for CADM1 relocation. Cytochemical studies showed that 3E1 colocalized with late endosomes/lysosomes after co-administration with 9D2, suggesting that the CADM1-antibody complex is internalized from the cell surface to intracellular compartments by lipid-raft mediated endocytosis. Finally, 3E1 was conjugated with the antimitotic agent monomethyl auristatin E (MMAE) via a cathepsin-cleavable linker. Co-administration of 3E1-monomethyl auristatin E and 9D2 suppressed the growth of multiple types of tumor cells, and this anti-tumor activity was confirmed in a syngeneic mouse model of melanoma. 3E1 and 9D2 are promising drug delivery vehicles for CADM1-expressing tumor cells.
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Anticuerpos Monoclonales , Molécula 1 de Adhesión Celular , Sistemas de Liberación de Medicamentos , Inmunoglobulinas , Animales , Humanos , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/inmunología , Inmunoglobulinas/administración & dosificación , Inmunoglobulinas/metabolismo , Línea Celular Tumoral , Ratones , Ratones Endogámicos C57BL , Oligopéptidos/administración & dosificación , Oligopéptidos/química , Inmunoglobulina M/inmunología , Inmunoglobulina M/administración & dosificación , Pollos , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/inmunología , FemeninoRESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) first infects the host nasal mucosa, where the viral spike protein binds to angiotensin-converting enzyme 2 (ACE2) on the mucosal cells. This study aimed at searching host cell surface molecules that could contribute to the infection in two views; abundance on host cells and affinity to the spike protein. Since the nasal mucosa is lined by respiratory and olfactory epithelia, and both express an immunoglobulin superfamily member cell adhesion molecule 1 (CADM1), whether CADM1 would participate in the spike protein binding was examined. Immunohistochemistry on the mouse nasal cavity detected CADM1 strongly in the olfactory epithelium at cell-cell contacts and on the apical surface but just faintly in the respiratory epithelium. In contrast, ACE2 was detected in the respiratory, not olfactory, epithelium. When mice were administered intranasally with SARS-CoV-2 S1 spike protein and an anti-CADM1 ectodomain antibody separately, both were detected exclusively on the olfactory, not respiratory, epithelium. Then, the antibody and S1 spike protein were administered intranasally to mice in this order with an interval of 1 hour. After 3 hours, S1 spike protein was detected as a protein aggregate floating in the nasal cavity. Next, S1 spike protein labeled with fluorescein was added to the monolayer cultures of epithelial cells exogenously expressing ACE2 or CADM1. Quantitative detection of fluorescein bound to the cells revealed that S1 spike protein bound to CADM1 with affinity half as high as to ACE2. Consistently, docking simulation analyses revealed that S1 spike protein could bind to CADM1 three quarters as strongly as to ACE2 and that the interface of ACE2 was similar in both binding modes. Collectively, intranasal S1 spike protein appeared to prefer to accumulate on the olfactory epithelium, and CADM1 was suggested to contribute to this preference of S1 spike protein based on the molecular abundance and affinity.
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Malignant pleural mesothelioma (MPM) is a highly aggressive malignant tumor, and the effective therapeutic drugs are limited. Thus, the establishment of novel therapeutic method is desired. Considerable proportion of MPMs are shown to express cell adhesion molecule 1 (CADM1), and to use CADM1 to bind to and proliferate on the pleural mesothelial surface, suggesting that CADM1 is a possible therapeutic target. Here, anti-CADM1 ectodomain chicken monoclonal antibodies, 3E1 and 9D2, were examined for their possible therapeutic utility. The full-length form of CADM1 was expressed in eight out of twelve human MPM cell lines. MPM cell lines were cultured on a confluent monolayer of mesothelial MeT-5A cells in the presence of 9D2, the neutralizing antibody. 9D2 suppressed the cell growth of CADM1-positive MPM cells with the loss and aggregation of CADM1 molecules on the MPM cell membrane, but not of CADM1-negative MPM cells. Co-addition of 3E1, lacking the neutralizing action, enhanced the growth-suppressive effect of 9D2. The two antibodies were tested as drug delivery vectors. 3E1 was converted into a humanized antibody (h3E1) and conjugated with monomethyl auristatin E (MMAE), a tubulin polymerization inhibitor. When the resulting h3E1-MMAE antibody-drug conjugate (ADC) was added to the standard cultures of CADM1-positive MPM cells, it suppressed the cell growth in a dose-dependent manner. Co-addition of 9D2 enhanced the growth-suppressive effect of h3E1-MMAE ADC. Anti-CADM1 ectodomain antibodies were suggested to serve as both antibody drugs and drug vectors in the treatment of MPM.
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AIMS: To characterize and evaluate oxidative secondary injury generated in heat-treated Escherichia coli cells during recovery cultivation either on agar or in a broth of a semi-synthetic enriched M9 (EM9) medium and a complex Luria broth (LB) medium with different types of antioxidants. METHODS AND RESULTS: E. coli cells grown in the EM9 and LB broth were heated at 50°C in a buffer (pH 7.0). Heated cells were recovered on the same kind of agar medium as that used for growth, with or without different antioxidants. Although these antioxidants mostly protected the cells from oxidative secondary injury on the recovery media, sodium thiosulphate and sodium pyruvate were most protective on EM9 and LB agars, respectively. Determination of viability using the most probable number and growth delay analysis methods showed significant reductions in the protective effects of antioxidants in the EM9 and LB media. CONCLUSION: Oxidative secondary injury generated in heated E. coli cells was found to be qualitatively and quantitatively diverse under cellular and environmental conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results suggest that different modes of oxidation should be considered in viability determination and injured cell enumeration of heat-treated cells.
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Infecciones por Escherichia coli , Escherichia coli , Agar/farmacología , Antioxidantes/farmacología , Medios de Cultivo/química , Calor , Humanos , Estrés Oxidativo , Ácido Pirúvico , Sodio/farmacologíaRESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uses its S1 spike protein to bind to angiotensin-converting enzyme 2 (ACE2) on human cells in the first step of cell entry. Tryptanthrin, extracted from leaves of the indigo plant, Polygonum tinctorium, using d-limonene (17.3 µg/ml), is considered to inhibit ACE2-mediated cell entry of another type of coronavirus, HCoV-NL63. The current study examined whether this extract could inhibit the binding of the SARS-CoV-2 spike protein to ACE2. Binding was quantified as cell-bound fluorescence intensity in live cell cultures in which canine kidney MDCK cells overexpressing ACE2 were incubated with fluorescein-labeled S1 spike protein. When indigo extract, together with S1 protein, was added at 8,650x and 17,300x dilutions, fluorescence intensity decreased in a dose- and S1 extract-dependent manner, without affecting cell viability. When 4.0-nM tryptanthrin was added instead of the indigo extract, fluorescence intensity also decreased, but to a lesser degree than with indigo extract. Docking simulation analyses revealed that tryptanthrin readily bound to the receptor-binding domain of the S1 protein, and identified 2- and 7-amino acid sequences as the preferred binding sites. The indigo extract appeared to inhibit S1-ACE2 binding at high dilutions, and evidently contained other inhibitory elements as well as tryptanthrin. This extract may be useful for the prevention or treatment of SARS-CoV-2 infection.
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Periodontitis is a chronic inflammatory disease caused by periodontopathogenic bacteria that form biofilms in periodontal pockets. The gingival epithelium acts as the first physical barrier in fighting attacks by periodontopathogenic pathogens, such as the primary etiological agent Porphyromonas gingivalis, and various exogenous chemicals, as well as regulates the local innate immune responses. Therefore, the development of novel oral care products to inhibit inflammatory reactions caused by bacterial infection and protect the gingival epithelium is necessary. Juncus effusus L. has generally been used as an indigenous medicine, such as a diuretic, an antipyretic, and an analgesic, in ancient practice. In this study, we examined the effects of a water extract from J. effusus L. on the inhibition of the inflammatory reaction elicited by bacterial infection and protection of the oral epithelium by chemical irritation. Pretreatment of oral epithelial cells with the water extract from J. effusus L. significantly reduced P. gingivalis or its lipopolysaccharide- (LPS-) mediated production of chemokines (interleukin-8 and C-C-chemokine ligand20) in a concentration-dependent manner with comparable to or greater effects than epigallocatechin gallate and protected oral epithelial cells from injury by chemical irritants, cetylpyridinium chloride, and benzethonium chloride. Moreover, the water extract from J. effusus L. in the presence of antimicrobial agents or antifibrinolytics already used as ingredients in mouthwash could significantly reduce the production of chemokines from P. gingivalis LPS-stimulated oral epithelial cells in a concentration-dependent manner. These findings suggest that the water extract from J. effusus L. is potentially useful for oral care to prevent oral infections, such as periodontal infections, and maintain oral epithelial function.
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Antiinflamatorios , Queratinocitos/metabolismo , Magnoliopsida/química , Mucosa Bucal/metabolismo , Extractos Vegetales , Antiinflamatorios/química , Antiinflamatorios/farmacología , Infecciones por Bacteroidaceae/metabolismo , Infecciones por Bacteroidaceae/prevención & control , Línea Celular Transformada , Humanos , Queratinocitos/patología , Mucosa Bucal/patología , Periodontitis/metabolismo , Periodontitis/patología , Periodontitis/prevención & control , Extractos Vegetales/química , Extractos Vegetales/farmacología , Porphyromonas gingivalis/metabolismoRESUMEN
AIMS: Cell adhesion molecule 1 (CADM1) mediates interepithelial adhesion and is upregulated in crowded epithelial monolayers. This study aimed to examine CADM1 expression in the human endometrium of proliferative and secretory phases, and its transcriptional regulation in terms of estrogen stimuli and higher cellularity. MAIN METHODS: CADM1 immunohistochemistry was conducted on endometrial tissues from women in their 40s and adult mice subcutaneously injected with estradiol following ovariectomy. Dual-luciferase reporter assays were conducted using human endometrial HEC-50B and HEC-1B cells and reporter plasmids harboring the human CADM1 3.4-kb promoter and its deleted and mutated forms. Cells were transfected with estrogen receptor α cDNA and reporter plasmids, and treated with estradiol before luciferase activity measurement. KEY FINDINGS: Immunohistochemistry revealed that CADM1 was clearly expressed on the lateral membranes of the simple columnar glandular cells in the proliferative phase, but not in the secretory phase, from both women and the mouse model. The glandular cell density increased two-fold in the proliferative phase. Reporter assays identified three Sp1-binding sites as estradiol-responsive elements in the proximal region (from -223 to -84) of the transcription start site (+1) in HEC-50B cells. When the cell culture was started at eight-fold higher cell density, the CADM1 3.4-kb promoter was transactivated at a two-fold higher level in HEC-50B cells. This cell density effect was not detected for the CADM1 2.3-kb or 1.6-kb promoter. SIGNIFICANCE: Two (proximal and distal) promoter regions are suggested to function additively to transactivate CADM1 in endometrial glandular cells that crowd in the proliferative phase.
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Molécula 1 de Adhesión Celular/biosíntesis , Proliferación Celular , Endometrio/metabolismo , Células Epiteliales/metabolismo , Regulación de la Expresión Génica , Adulto , Animales , Molécula 1 de Adhesión Celular/genética , Línea Celular Tumoral , Estrógenos/farmacología , Femenino , Humanos , RatonesRESUMEN
The Vilsmeier reagent (VR), first reported a century ago, is a versatile reagent in a variety of organic reactions. It is used extensively in formylation reactions. However, the synthesis of VR generally requires highly toxic and corrosive reagents such as POCl3, SOCl2, or COCl2. In this study, we found that VR is readily obtained from a CHCl3 solution containing N,N-dimethylformamide or N,N-dimethylacetamide upon photo-irradiation under O2 bubbling. The corresponding Vilsmeier reagents were obtained in high yields with the generation of gaseous HCl and CO2 as byproducts to allow their isolations as crystalline solid products amenable to analysis by X-ray crystallography. With the advantage of using CHCl3, which bifunctionally serves as a reactant and a solvent, this photo-on-demand VR synthesis is available for one-pot syntheses of aldehydes, acid chlorides, formates, ketones, esters, and amides.
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Bacillus pumilus has rarely been reported as a cause of human infections. We report a case of a B. pumilus causing food poisoning in an adult male. A 51-year-old Japanese man complained of severe abdominal cramps, fever with chills, diarrhea, dizziness, and loss of appetite after eating reheated rice with stewed minced meat purchased from a Kenyan restaurant. Bacillus pumilus was isolated from blood culture and was identified using a biochemical test and 16S rRNA gene sequencing analysis. The patient was treated with probiotics and ciprofloxacin and recovered after 3 days. To our knowledge, this is the first report describing the potential role of B. pumilus as a foodborne pathogen in Kenya and highlights the importance of good hygiene and food preparation practices.
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Bacillus pumilus , Enfermedades Transmitidas por los Alimentos/microbiología , Infecciones por Bacterias Grampositivas/microbiología , Antibacterianos/uso terapéutico , Ciprofloxacina/uso terapéutico , Heces/microbiología , Enfermedades Transmitidas por los Alimentos/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana EdadRESUMEN
We report a case of colorectal cancer associated with Crohn's disease in a 50-year-old man. He had been diagnosed with Crohn's disease 26 years before and had undergone sigmoidectomy for sigmoid colon stenosis 19 years before. Ileal resection, was performed for ileus stenosis 12 years before. Three years before, partial resection of the small intestine was performed for perforation of the small intestine. During this period, the medical treatment was continued, but the patient experienced remission and exacerbation. He complained of anal pain at a regular outpatient visit, and endoscopic examination showed an elevated lesion immediately above the dentate line. Adenocarcinoma Group 5 was detected on biopsy. The diagnosis was rectal cancer(cT2N3M0, Stageâ ¢b). We performed an abdominoperineal resection, a D3 lymph node dissection, and colostomy. Chemotherapy with mFOLFOX6 was provided postoperatively. The patient has survived without recurrence for 1 year and 6 months after the surgery.
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Enfermedad de Crohn , Neoplasias del Recto , Enfermedad de Crohn/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Neoplasias del Recto/etiología , Neoplasias del Recto/cirugíaRESUMEN
BACKGROUND: The epidemiology of enteric pathogens has not been well studied in Kenya because of wide disparities in health status across the country. Therefore, the present study describes the prevalence of enteropathogenic bacteria, their seasonal variation, and antibiotic resistance profiles among hospitalized diarrheic children in a suburban region of central Kenya. METHODS: Fecal samples were collected between July 2009 and December 2013 from a total of 1410 children younger than 5 years, hospitalized with acute diarrhea in Kiambu County Hospital, Kenya. Conventional culture, biochemical, and molecular methods were conducted to identify causative bacterial pathogens and their virulence factors. Antimicrobial susceptibility tests were performed using E-test strips and VITEK-2 advanced expert system (AES) to evaluate the drug-resistance pattern of the isolates. RESULTS: Of the 1410 isolates, bacterial infections were identified in 474 cases. Diarrheagenic Escherichia coli (DEC) was the most frequently isolated pathogen (86.5%). Other pathogens such as Aeromonas (5.5%), Shigella (4%), Salmonella (3.4%), Providencia (3.2%), Vibrio spp. (1.1%), Yersinia enterocolitica (1.1%), and Plesiomonas shigelloides (0.2%) were also identified. Mixed bacterial infection was observed among 11.1% of the cases. The highest infection rate was found during the dry season (59.3%, p = 0.04). Most of the DEC was found to be multidrug resistant to trimethoprim/sulfamethoxazole 97.6%, amoxicillin 97.6%, erythromycin 96.9%, ampicillin 96.6%, and streptomycin 89%. CONCLUSIONS: This study suggests that DEC is the leading diarrhea-causing bacterial pathogen circulating in central Kenya, and seasonality has a significant effect on its transmission. Proper antibiotic prescription and susceptibility testing is important to guide appropriate antimicrobial therapy.
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Artificial peptides designed for molecular recognition of a bacterial toxin have been developed. Vacuolating cytotoxin A protein (VacA) is a major virulence factor of Helicobacter pylori, a gram-negative microaerophilic bacterium inhabiting the upper gastrointestinal tract, particularly the stomach. This study attempted to identify specific peptide sequences with high affinity for VacA using systematic directed evolution in vitro, a cDNA display method. A surface plasmon resonance-based biosensor and fluorescence correlation spectroscopy to examine binding of peptides with VacA identified a peptide (GRVNQRL) with high affinity. Cyclization of the peptide by attaching cysteine residues to both termini improved its binding affinity to VacA, with a dissociation constant (Kd ) of 58 nm. This study describes a new strategy for the development of artificial functional peptides, which are promising materials in biochemical analyses and medical applications.
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Toxinas Bacterianas/metabolismo , ADN Complementario/genética , Helicobacter pylori/metabolismo , Péptidos/química , Péptidos/metabolismo , Toxinas Bacterianas/genética , Unión ProteicaRESUMEN
Alarin is an alternative-splicing form of GALP (galanin-like peptide). It shares only 5 conserved amino acids at the N-terminal region with GALP which is involved in a diverse range of normal brain functions. This study seeks to investigate whether alarin has additional functions due to its differences from GALP. Here, we have shown using a radial diffusion assay that alarin but not GALP inhibited the growth of Escherichia coli (strain ML-35). The conserved N-terminal region, however, remained essential for the antimicrobial activity of alarin as truncated peptides showed reduced killing effect. Moreover, alarin inhibited the growth of E. coli in a similar potency as human cathelicidin LL-37, a well-studied antimicrobial peptide. Electron microscopy further showed that alarin induced bacterial membrane blebbing but unlike LL-37, it did not cause hemolysis of erythrocytes. In addition, alarin is only active against the gram-negative bacteria, E. coli but not the gram-positive bacteria, Staphylococcus aureus. Thus, these data suggest that alarin has potentials as an antimicrobial and should be considered for the development in human therapeutics.
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Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Péptido Similar a Galanina/análogos & derivados , Péptido Similar a Galanina/farmacología , Secuencia de Aminoácidos , Animales , Péptidos Catiónicos Antimicrobianos , Catelicidinas/farmacología , Membrana Celular/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Escherichia coli/ultraestructura , Hemólisis , Caballos/sangre , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Datos de Secuencia Molecular , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrolloRESUMEN
This study aimed to determine the relationship between human papillomavirus (HPV) and nuclear factor-κB (NF-κB) in cervical cancer using 62 tissues of cervical cancer, and to compare the findings to penile cancer. HPV-DNA integration is a crucial factor for malignant transformation in cervical cancer and can be identified using in situ hybridization. Of the 62 cases, HPV infection was detected in 28 (45.2%). This frequency was lower than in penile cancer (68.2%) as shown by our previous study. The earliest age of onset of cervical and penile cancer was 18 and 35, respectively, whereas the mean age of the initial diagnosis of cervical and penile cancer was 50.1 and 59.6, respectively. The discrepancies of HPV prevalence, earliest ages of onset and mean ages between cervical and penile cancer patients may result from the gender-based synergistic action of HPV associated with multiple epidemiological co-factors. Of the 28 HPV-infected cases, NF-κB expression was observed in the nucleus in 18 (64.3%), in the cytoplasm in 19 (67.9%) and in the nucleus and/or cytoplasm in 27 cases (96.4%). The overexpression of NF-κB in cervical cancer cases suggests that NF-κB activation is a key modulator in driving chronic inflammation to cancer.
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The study evaluated the antibiotic resistance patterns of Helicobacter pylori strains against metronidazole and clarithromycin in a hospital in Havana, Cuba. Eighty-five percent, 22.5%, and 10% of 40 H. pylori strains investigated were resistant to metronidazole, ciprofloxacin, and clarithromycin respectively but all were susceptible to amoxicillin and tetracycline. RdxA truncation was found only in metronidazole-resistant strains. In such strains, reported are eight and two novel mutations in the rdxA and frxA genes respectively. Two-point mutations in the 23S rRNA genes of clarithromycin-resistant strains were detected. A high prevalence of metronidazole resistance was found in Cuban H. pylori strains. Mutations in the rdxA gene may contribute more significantly than frxA gene to the high level of resistance to metronidazole. This study supports the need to continue monitoring the antibiotic susceptibility in H. pylori in Cuba to guide the treatment of such infection.
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Antibacterianos/farmacología , Antiinfecciosos/farmacología , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/genética , Mutación/genética , Adulto , Factores de Edad , Anciano , Amoxicilina/farmacología , Ciprofloxacina/farmacología , Claritromicina/farmacología , Cuba , Farmacorresistencia Bacteriana/genética , Femenino , Helicobacter pylori/clasificación , Humanos , Masculino , Metronidazol/farmacología , Pruebas de Sensibilidad Microbiana/métodos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , Análisis de Secuencia de ADN/métodos , Factores Sexuales , Especificidad de la Especie , Tetraciclina/farmacología , Adulto JovenRESUMEN
Gangliosides are target receptors for bacterial entry, yet those present in human milk exhibit a protective role against bacterial infection. Here, we show that treatment with ganglioside mixture at a concentration of 100 microg/mL resulted in significant inhibition of the vacuole formation activity of Helicobacter pylori vacuolating cytotoxin (VacA) in gastric epithelial cancer AZ-521 cells. All gangliosides (GM1, GM2, GM3, GD1a, GD1b, GD3 and GT1b) examined showed good neutralizing capacity against VacA. A pull-down assay was performed using lyso-GM1 coupled to Sepharose as the tagged polysaccharide polymer to capture VacA from H. pylori culture supernatant. GM1-VacA complexes were successfully precipitated, suggesting that GM1 binds directly to VacA. The hydrodynamic binding of lyso-GM1 and VacA measured by fluorescence correlation spectroscopy had a K(d) value of 190 nM. VacA also bound to lyso-GM1 at pH 2 corresponding to the physiological pH of human stomach. Collectively, these results showed that direct binding of H. pylori VacA to free gangliosides neutralizes the toxin activity of VacA. These findings offer an alternative insight into the role of gangliosides in VacA toxicity and the pathogenesis of H. pylori.
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Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/toxicidad , Gangliósidos/metabolismo , Proteínas Bacterianas/metabolismo , Sitios de Unión , Línea Celular Tumoral , Gangliósidos/farmacología , Humanos , Espectrometría de FluorescenciaRESUMEN
The causal relationship between chronic inflammation and cancer is widely accepted. Numerous investigations have identified nuclear factor-κB (NF-κB) as an important modulator in driving chronic inflammation to cancer. This study aimed to determine the prevalence of human papillomavirus (HPV) in penile cancer in Japanese patients and whether NF-κB is subsequently overexpressed in penile cancer. Thirty-four specimens of penile tissue (16 malignant and 18 benign cases) were examined to determine the association of HPV infection. An in situ hybridization (ISH) method was used to detect and localize HPV-DNA. A sensitive HPV polymerase chain reaction (PCR) procedure was used for the detection of HPV-DNA, and DNA sequencing was used to identify the HPV genotype. HPV-DNA was detected in 37.5 and 75% of cases of penile cancer, using ISH and PCR, respectively. Our efforts to detect HPV genotypes were unsuccessful as HPV-DNA could not be extracted from these materials. Using ISH, a prevalence of 68.2% of HPV infection was found in penile cancer in Kenyan patients in east Africa. In the present study, all 9 HPV-positive cases, (100%) were NF-κB-positive in the nucleus and/or cytoplasm. In contrast, of the 25 HPV-negative cases, 15 (60%) were NF-κB-positive in the nucleus and/or cytoplasm. Therefore, ISH is a method which is able to prove infection of a large quantity of HPV more effectively when compared with PCR. Thus, a large quantity of HPV infection leads to the activity of NF-κB. The most prevalent genotype was the HPV-22 found in 83.3% of the penile cancer cases. In addition, HPV-11 was found in 81.8% of the non-cancer cases. For cases with a high level of infection, the activity of NF-κB increased compared with those with a low level of HPV infection.
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Human papillomavirus (HPV) E6 and E7 oncoproteins are essential factors for HPV oncogenesis. These E6 and E7 gene products play a central role in the induction of malignant transformation by interacting with several cellular regulatory proteins such as p16(INK4a), p53 and nuclear factor κB (NF-κB). In the present study, conducted in northern Thailand, HPV-DNA was detected in penile cancer cases using an in situ hybridization procedure and p16(INK4a), p53 and NF-κB were detected by immunohistochemistry. Using the cell cycle regulatory proteins p16(INK4a) (61.5%) and p53 (71.8%), it was found that of the 51 cases, 39 (76.5%) were HPV-DNA-positive in penile cancer. On the other hand, 25% p16(INK4a) and 75% p53, respectively, were found in HPV-negative cases. Prevalence of HPV infection (76.5%) was shown in penile cancer cases in northern Thailand. No difference was found between HPV-positive and HPV-negative cases with respect to the presence of the cell cycle regulatory protein p53. On the other hand, p16(INK4a) was found to be different between HPV-positive and HPV-negative cases. Inactivation of tumor suppressor genes, such as p16(INK4a) and p53, to genetic instability, cell immortalization, accumulation of mutations and cancer formation, with or without HPV and irrespective of HPV infection, is therefore suggested. Of the 39 HPV-positive cases, 35 (89.7%) were NF-κB-positive in the nucleus, 29 (74.4%) in the cytoplasm and 37 (94.9%) in the nucleus and/or cytoplasm. NF-κB was detected in 4 (33.3%) of the 12 HPV-negative cases. Therefore, we propose that penile cancer cases with HPV infection are more likely to activate NF-κB than those without HPV infection.
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BACKGROUND: Information is limited about how adipokines predict the accumulation of cardiovascular (CV) risk factors or the presence of metabolic syndrome (MS) in children. METHODS AND RESULTS: The subjects were 321 children (200 boys and 121 girls; 109 normal and 212 obese) aged 6-12 years. Obesity was defined as a body mass index of >or= the 95(th) percentile for age and sex. MS was defined by using the newly established Task Force criteria. The levels of the adipokines--adiponectin, leptin, ghrelin, high sensitive C-reactive protein (CRP) and resistin--were measured. Regression analyses revealed that high leptin levels were predictive of the accumulation of CV risk factors in normal weight, obese, and entire (normal weight and obese) group of subjects. High CRP in the normal weight group and low adiponectin in the obese and the entire groups were also independently predictive of the accumulation of risk factors. A high leptin level was solely predictive of the presence of MS in obese and entire groups. CONCLUSIONS: Leptin was the most sensitive marker for predicting the accumulation of CV risk factors and the presence of MS in elementary school children. Primary prevention is important because both leptin and adiponectin levels abruptly worsened when children obtained any 1 risk factor.