RESUMEN
The red blood cells (RBCs) of vertebrates have evolved into two basic shapes, with nucleated nonmammalian RBCs having a biconvex ellipsoidal shape and anuclear mammalian RBCs having a biconcave disk shape. In contrast, camelid RBCs are flat ellipsoids with reduced membrane deformability, suggesting altered membrane skeletal organization. However, the mechanisms responsible for their elliptocytic shape and reduced deformability have not been determined. We here showed that in alpaca RBCs, protein 4.1R, a major component of the membrane skeleton, contains an alternatively spliced exon 14-derived cassette (e14) not observed in the highly conserved 80 kDa 4.1R of other highly deformable biconcave mammalian RBCs. The inclusion of this exon, along with the preceding unordered proline- and glutamic acid-rich peptide (PE), results in a larger and unique 90 kDa camelid 4.1R. Human 4.1R containing e14 and PE, but not PE alone, showed markedly increased ability to form a spectrin-actin-4.1R ternary complex in viscosity assays. A similar facilitated ternary complex was formed by human 4.1R possessing a duplication of the spectrin-actin-binding domain, one of the mutations known to cause human hereditary elliptocytosis. The e14- and PE-containing mutant also exhibited an increased binding affinity to ß-spectrin compared with WT 4.1R. Taken together, these findings indicate that 4.1R protein with the e14 cassette results in the formation and maintenance of a hyperstable membrane skeleton, resulting in rigid red ellipsoidal cells in camelid species, and suggest that membrane structure is evolutionarily regulated by alternative splicing of exons in the 4.1R gene.
Asunto(s)
Empalme Alternativo , Camélidos del Nuevo Mundo , Forma de la Célula , Proteínas del Citoesqueleto , Eritrocitos , Animales , Humanos , Actinas/metabolismo , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/metabolismo , Eritrocitos/citología , Eritrocitos/metabolismo , Membranas/metabolismo , Péptidos/metabolismo , Unión Proteica , Espectrina/genética , Espectrina/metabolismo , Forma de la Célula/genéticaRESUMEN
The tumor microenvironment (TME) consists of cancer cells surrounded by stromal components including tumor vessels. Transforming growth factor-ß (TGF-ß) promotes tumor progression by inducing epithelial-mesenchymal transition (EMT) in cancer cells and stimulating tumor angiogenesis in the tumor stroma. We previously developed an Fc chimeric TGF-ß receptor containing both TGF-ß type I (TßRI) and type II (TßRII) receptors (TßRI-TßRII-Fc), which trapped all TGF-ß isoforms and suppressed tumor growth. However, the precise mechanisms underlying this action have not yet been elucidated. In the present study, we showed that the recombinant TßRI-TßRII-Fc protein effectively suppressed in vitro EMT of oral cancer cells and in vivo tumor growth in a human oral cancer cell xenograft mouse model. Tumor cell proliferation and angiogenesis were suppressed in tumors treated with TßRI-TßRII-Fc. Molecular profiling of human cancer cells and mouse stroma revealed that K-Ras signaling and angiogenesis were suppressed. Administration of TßRI-TßRII-Fc protein decreased the expression of heparin-binding epidermal growth factor-like growth factor (HB-EGF), interleukin-1ß (IL-1ß) and epiregulin (EREG) in the TME of oral cancer tumor xenografts. HB-EGF increased proliferation of human oral cancer cells and mouse endothelial cells by activating ERK1/2 phosphorylation. HB-EGF also promoted oral cancer cell-derived tumor formation by enhancing cancer cell proliferation and tumor angiogenesis. In addition, increased expressions of IL-1ß and EREG in oral cancer cells significantly enhanced tumor formation. These results suggest that TGF-ß signaling in the TME controls cancer cell proliferation and angiogenesis by activating HB-EGF/IL-1ß/EREG pathways and that TßRI-TßRII-Fc protein is a promising tool for targeting the TME networks.
Asunto(s)
Neoplasias de la Boca , Proteínas Serina-Treonina Quinasas , Humanos , Ratones , Animales , Proteínas Serina-Treonina Quinasas/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Similar a EGF de Unión a Heparina , Células Endoteliales/metabolismo , Microambiente Tumoral , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factor de Crecimiento Transformador beta1 , Neoplasias de la Boca/genética , Factores de Crecimiento TransformadoresRESUMEN
BACKGROUND: Non-Helicobacter pylori Helicobacter (NHPH) is rarely detected in duodenal mucosa due to its preference for slightly acidic environments. Here, we report four cases of NHPH-infected gastritis with duodenal spiral bacilli, potentially NHPH, indicating the possibility of duodenal mucosal infection. CASE PRESENTATION: In every case, gastric mucosa showed endoscopic findings characteristic of NHPH-infected gastritis, and a mucosal biopsy was taken from the duodenal bulb; spiral bacilli were identified under microscopy using Giemsa staining. Case 1, a 46-year-old man, had diffuse spotty redness, mucosal edema, and multiple tiny erosions in the duodenal bulb, along with larger erosions in the second portion of the duodenum upon endoscopic examination. Histopathologically, moderate infiltration of mononuclear cells and neutrophils in the lamina propria and gastric epithelial metaplasia were observed. Case 2, a 54-year-old man, showed an elevated lesion, 1 cm in diameter, with multiple red spots and a few tiny erosions in the duodenal bulb. Histopathologically, mild inflammatory cell infiltration and gastric epithelial metaplasia were observed. In Case 3, a 52-year-old man, endoscopy revealed a flat elevated lesion, 7 mm in diameter, with multiple red spots and a few tiny erosions in the anterior wall of the duodenal bulb. Histopathologically, we observed moderate inflammatory cell infiltration in the gastric antrum and gastric epithelial metaplasia in the duodenal bulb. Case 4, a 40-year-old man, showed mild spotty redness in the duodenal bulb. Histopathologically, mild mononucleocyte infiltration and gastric epithelial metaplasia were observed. A single spiral bacillus was observed in Case 4 by microscopy. In all but Case 2, Helicobacter suis was identified in the gastric juice by polymerase chain reaction analysis. CONCLUSIONS: Spiral bacilli resembling NHPH may infect the duodenal mucosa, particularly the bulb, causing inflammation. Gastric contents entering the duodenum may reduce the intraduodenal pH, promoting NHPH survival and proliferation.
Asunto(s)
Duodeno , Gastritis , Infecciones por Helicobacter , Humanos , Masculino , Persona de Mediana Edad , Gastritis/microbiología , Gastritis/patología , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/patología , Infecciones por Helicobacter/complicaciones , Duodeno/patología , Duodeno/microbiología , Biopsia , Helicobacter/aislamiento & purificación , Helicobacter/fisiología , Helicobacter/genética , Adulto , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Mucosa Gástrica/microbiología , Mucosa Gástrica/patologíaRESUMEN
BACKGROUND: At present, eradication regimens for non-Helicobacter pylori Helicobacter (NHPH) have not been established yet. We investigated effectiveness of the standard triple-drug combination therapy for Helicobacter pylori eradication and of a proton pump inhibitor (PPI) monotherapy in eradication of NHPH. METHODS: Subjects were the patients who were diagnosed with NHPH-infected gastritis based on microscopic findings, helical-shaped organisms obviously larger than Helicobacter pylori, in the gastric mucosal specimens using Giemsa staining at Kenwakai Hospital between November 2010 and September 2021, whose NHPH species were identified by polymerase chain reaction (PCR) analysis of urease genes in endoscopically-biopsied samples, and who consented to NHPH eradication with either the triple-drug combination therapy for one week or a PPI monotherapy for six months. Six months after the completion of eradication, its result was determined with esophagogastroduodenoscopy, microscopic examination, and PCR analysis. In cases of unsuccessful eradication, a second eradication with the other therapy was suggested to the patient. RESULTS: PCR analysis detected NHPH in 38 patients: 36 as Helicobacter suis and two as Helicobacter heilmannii/Helicobacter ailurogastricus. Fourteen Helicobacter suis-infected and one Helicobacter heilmannii/Helicobacter ailurogastricus-infected patients requested eradication therapy. The triple-drug combination therapy succeeded in four of five patients, while the PPI monotherapy succeeded in five of 10 patients. Three of five patients who had been unsuccessful with the latter therapy requested the triple-drug combination therapy as the second eradication and all three were successful. In total, the triple-drug combination therapy succeeded in seven out of eight (87.5%) attempted cases, while the PPI monotherapy in five out of 10 (50%) attempted cases. CONCLUSIONS: In NHPH eradication, the triple-drug combination therapy was considered to be effective to some extent and to become the first-line therapy. While, although less successful, PPI monotherapy appeared to be a potentially promising option particularly for patients with allergy or resistance to antibiotics. Effectiveness of PPI monotherapy may be attributed to hyperacid environment preference of Helicobacter suis and PPI's acid-suppressive effect. Additionally, male predominance in NHPH-infected gastritis patients may be explained by gender difference in gastric acid secretory capacity. However, further evidence needs to be accumulated. STUDY REGISTRATION: This study was approved by the Research Ethics Committee of Kenwakai Hospital (No. 2,017,024).
Asunto(s)
Antibacterianos , Quimioterapia Combinada , Gastritis , Infecciones por Helicobacter , Helicobacter heilmannii , Inhibidores de la Bomba de Protones , Inhibidores de la Bomba de Protones/administración & dosificación , Inhibidores de la Bomba de Protones/uso terapéutico , Humanos , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Masculino , Femenino , Persona de Mediana Edad , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Gastritis/tratamiento farmacológico , Gastritis/microbiología , Adulto , Anciano , Helicobacter heilmannii/aislamiento & purificación , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/aislamiento & purificación , Amoxicilina/administración & dosificación , Amoxicilina/uso terapéutico , Claritromicina/administración & dosificación , Claritromicina/uso terapéutico , Helicobacter/aislamiento & purificación , Helicobacter/efectos de los fármacos , Resultado del Tratamiento , Mucosa Gástrica/microbiología , Mucosa Gástrica/patologíaRESUMEN
INTRODUCTION: Carbon dioxide-dependent Proteus mirabilis has been isolated from clinical specimens. It is not clear whether mutations in carbonic anhydrase are responsible for the carbon dioxide dependence of P. mirabilis. The pathogenicity of carbon dioxide-dependent P. mirabilis also remains unclear. The purpose of this study was to determine the cause carbon dioxide dependence of P. mirabilis and its pathogenicity. METHODS: The DNA sequence of can encoding carbonic anhydrase of a carbon dioxide-dependent P. mirabilis small colony variant (SCV) isolate was analyzed. To confirm that impaired carbonic anhydrase activity is responsible for the formation of the carbon dioxide-dependent SCV phenotype of P. mirabilis, we performed complementation experiments using plasmids with intact can. Additionally, mouse infection experiments were performed to confirm the change in virulence due to the mutation of carbonic anhydrase. RESULTS: We found that the can gene of the carbon dioxide-dependent P. mirabilis SCV isolate showed had a frameshift mutation with a deletion of 1 bp (c. 173delC). The can of P. mirabilis encodes carbonic anhydrase was also found to function in Escherichia coli. The cause of the carbon dioxide-dependent SCV phenotype of P. mirabilis was an abnormality in carbonic anhydrase. Nevertheless, no changes were observed in virulence due to the mutation of carbonic anhydrase in mouse infection experiments. CONCLUSIONS: The can gene is essential for the growth of P. mirabilis in ambient air. The mechanisms underlying this fitness advantage in terms of infection warrant further investigation.
Asunto(s)
Dióxido de Carbono , Anhidrasas Carbónicas , Infecciones por Proteus , Proteus mirabilis , Proteus mirabilis/genética , Proteus mirabilis/patogenicidad , Proteus mirabilis/aislamiento & purificación , Dióxido de Carbono/metabolismo , Animales , Ratones , Infecciones por Proteus/microbiología , Anhidrasas Carbónicas/genética , Anhidrasas Carbónicas/metabolismo , Humanos , Virulencia/genética , Femenino , Mutación del Sistema de LecturaRESUMEN
Hepatitis B virus (HBV) infects 240 million people worldwide. Current therapy profoundly suppresses HBV replication but requires long-term maintenance therapy. Therefore, there is still a medical need for an efficient HBV cure. HBV enters host cells by binding via the preS1 domain of the viral L protein to the Na+/taurocholate cotransporting polypeptide (NTCP). Thus, NTCP should be a key target for the development of anti-HBV therapeutics. Indeed, myrcludex B, a synthetic form of the myristoylated preS1 peptide, effectively reduces HBV/hepatitis D virus (HDV) infection and has been approved as Hepcludex in Europe for the treatment of patients with chronic HDV infection. We established a monoclonal antibody (MAb), N6HB426-20, that recognizes the extracellular domain of human NTCP and blocks HBV entry in vitro into human liver cells but has much less of an inhibitory effect on bile acid uptake. In vivo, administration of the N6HB426-20 MAb prevented HBV viremia for an extended period of time after HBV inoculation in a mouse model system without strongly inhibiting bile acid absorption. Among the extracellular loops (ECLs) of NTCP, regions of amino acids (aa) 84 to 87 in ECL1 and aa 157 to 165 near ECL2 of transmembrane domain 5 are critically important for HBV/HDV infection. Epitope mapping and the three-dimensional (3D) model of the NTCP structure suggested that the N6HB426-20 MAb may recognize aa 276/277 at the tip of ECL4 and interfere with binding of HBV to the region from aa 84 to 87. In summary, we identified an in vivo neutralizing NTCP-targeting antibody capable of preventing HBV infection. Further improvements in efficacy of this drug will pave the way for its clinical applications. IMPORTANCE A number of entry inhibitors are being developed to enhance the treatment of HBV patients with oral nucleoside/nucleotide analogues (NA). To amplify the effectiveness of NA therapy, several efforts have been made to develop therapeutic MAbs with neutralizing activity against HBs antigens. However, the neutralizing effect of these MAbs may be muted by a large excess of HBsAg-positive noninfectious particles in the blood of infected patients. The advantage of NTCP-targeted HBV entry inhibitors is that they remain effective regardless of viral genotype, viral mutations, and the presence of subviral particles. Although N6HB426-20 requires a higher dose than myrcludex to obtain equivalent suppression of HBV in a model mouse system, it maintained the inhibitory effect for a long time postadministration in proportion to the half-life of an IgG MAb. We believe that further improvements will make this antibody a promising treatment option for patients with chronic hepatitis B.
Asunto(s)
Virus de la Hepatitis B , Hepatitis B , Transportadores de Anión Orgánico Sodio-Dependiente , Simportadores , Internalización del Virus , Animales , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales/farmacología , Anticuerpos Monoclonales/uso terapéutico , Células Hep G2 , Hepatitis B/tratamiento farmacológico , Hepatitis B/prevención & control , Hepatitis B/virología , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/metabolismo , Hepatocitos , Humanos , Ratones , Transportadores de Anión Orgánico Sodio-Dependiente/metabolismo , Simportadores/metabolismo , Proteínas Virales/metabolismo , Internalización del Virus/efectos de los fármacosRESUMEN
A small-colony variant (SCV) of carbon dioxide-dependent Escherichia coli was isolated from a patient with acute bacterial cystitis. After the urine sample was inoculated on 5% sheep blood agar and incubated overnight at 35 °C in ambient air, no colony formation was observed. However, after overnight incubation at 35 °C in 5% CO2-enhanced ambient air, numerous colonies were obtained. We failed to characterize or identify the SCV isolate using the MicroScan WalkAway-40 System because the isolate did not grow in the system. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S rRNA sequencing were useful for identifying this SCV isolate. Genome sequencing analysis of the isolates revealed the presence of an 11-bp deletion mutation leading to premature translational truncation in the carbonic anhydrase gene, can, and the presence of 10 known antimicrobial resistance genes. The results of the antimicrobial susceptibility tests performed under CO2-enhanced ambient air were consistent with the presence of antimicrobial resistance genes. Our results also showed that Can is important to grow E. coli in ambient air, and that antimicrobial susceptibility testing of carbon dioxide-dependent SCVs should be performed in 5% CO2-enhanced ambient air. A revertant strain was obtained by passaging the SCV isolate, but the deletion mutation in can remained. To the best of our knowledge, this is the first case in Japan of acute bacterial cystitis caused by carbon dioxide-dependent E. coli with a deletion mutation in can.
Asunto(s)
Infecciones Bacterianas , Cistitis , Animales , Ovinos/genética , Escherichia coli/genética , Dióxido de Carbono , ARN Ribosómico 16S/genética , Eliminación de Secuencia , MutaciónRESUMEN
A hemin-requiring Proteus vulgaris small-colony variant (SCV) was isolated from a urine culture. This isolate was grown on 5% sheep blood agar but not on modified Drigalski agar. The single nucleotide substitution was found in the SCV of the hemC gene (c.55C > T), and this substitution caused a nonsense mutation (p.Gln19Ter). Porphyrin test results showed that the biosynthesis of δ-aminolevulinic acid stopped up to porphobilinogen and not pre-uroporphyrinogen due to a mutation in the hemC gene. To our knowledge, this is the first report of hemin-requiring P. vulgaris.
Asunto(s)
Hemina , Porfirinas , Animales , Ovinos , Proteus vulgaris/genética , Agar , Medios de CultivoRESUMEN
Here, we report a 60-year-old chronically bedridden man with cerebral palsy who had septic shock following a history of urinary tract infection with extended spectrum ß-lactamase-producing and auxotrophic Proteus mirabilis detected on blood and urine cultures. This auxotroph formed small colonies only on the blood agar at 24 h in 5% CO2, but not in the conditions without CO2, and lacked motility and some biochemical activities. The five-year history of stones in the right renal pelvis suggests chronic urinary tract infection with P. mirabilis requiring a 28-day antibiotic treatment. This paper highlights that the CO2-dependent P. mirabilis small colony variant may cause sepsis, probably due to chronic infection in uroliths, which should warrant immediate identification.
Asunto(s)
Infecciones por Proteus , Choque Séptico , Antibacterianos/uso terapéutico , Personas Encamadas , Dióxido de Carbono , Humanos , Masculino , Persona de Mediana Edad , Infección Persistente , Infecciones por Proteus/tratamiento farmacológico , Proteus mirabilis , Choque Séptico/tratamiento farmacológico , beta-Lactamasas/genéticaRESUMEN
INTRODUCTION: Small-colony variants (SCVs) of bacteria are subpopulations with a small colony size, low growth rate, and atypical colony morphology. The purpose of this study was to comprehensively elucidate the characteristics and underlying mechanism of the development of a glutamine-dependent SCV of E. coli, GU-92SCV, isolated from the blood of a patient with pyelonephritis. METHODS: The GU-92SCV strain was tested for auxotrophy testing for glutamine. DNA mutations in genes related to glutamine synthesis were analysed by sequencing. The isolate's proliferation and antimicrobial susceptibility in Mueller-Hinton II medium supplemented with glutamine were examined. RESULTS: The colony of the GU-92SCV strain did not grow on Mueller-Hinton II agar, but growth around the filter paper containing l-glutamine was enhanced on Mueller-Hinton II agar. The GU-92SCV strain had a single nucleotide substitution in glnA, c.193G>A, corresponding to p.Asp65Asn. Changing c.193G>A to the wild-type sequence in glnA restored these phenotypes. Because GU-92SCV did not grow in Mueller-Hinton II broth, antimicrobial susceptibility test results were not obtained; however, in the presence of 10 mg mL-1l-glutamine, the results were consistent with those of the revertant strain GU-92REV. CONCLUSION: To the best of our knowledge, this is the first clinical isolation of a glutamine-dependent E. coli SCV from a patient blood culture. Our data showed that glnA was important for the growth of E. coli in Mueller-Hinton II medium, which also required the presence of glutamine when performing antimicrobial susceptibility testing for glutamine-dependent SCV strains.
Asunto(s)
Antiinfecciosos , Infecciones por Escherichia coli , Escherichia coli , Glutamato-Amoníaco Ligasa , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Infecciones por Escherichia coli/tratamiento farmacológico , Glutamato-Amoníaco Ligasa/genética , Glutamina/genética , Humanos , Mutación MissenseRESUMEN
Tumor progression is governed by various growth factors and cytokines in the tumor microenvironment (TME). Among these, transforming growth factor-ß (TGF-ß) is secreted by various cell types residing in the TME and promotes tumor progression by inducing the epithelial-to-mesenchymal transition (EMT) of cancer cells and tumor angiogenesis. TGF-ß comprises three isoforms, TGF-ß1, -ß2, and -ß3, and transduces intracellular signals via TGF-ß type I receptor (TßRI) and TGF-ß type II receptor (TßRII). For the purpose of designing ligand traps that reduce oncogenic signaling in the TME, chimeric proteins comprising the ligand-interacting ectodomains of receptors fused with the Fc portion of immunoglobulin are often used. For example, chimeric soluble TßRII (TßRII-Fc) has been developed as an effective therapeutic strategy for targeting TGF-ß ligands, but several lines of evidence indicate that TßRII-Fc more effectively traps TGF-ß1 and TGF-ß3 than TGF-ß2, whose expression is elevated in multiple cancer types. In the present study, we developed a chimeric TGF-ß receptor containing both TßRI and TßRII (TßRI-TßRII-Fc) and found that TßRI-TßRII-Fc trapped all TGF-ß isoforms, leading to inhibition of both the TGF-ß signal and TGF-ß-induced EMT of oral cancer cells, whereas TßRII-Fc failed to trap TGF-ß2. Furthermore, we found that TßRI-TßRII-Fc suppresses tumor growth and angiogenesis more effectively than TßRII-Fc in a subcutaneous xenograft model of oral cancer cells with high TGF-ß expression. These results suggest that TßRI-TßRII-Fc may be a promising tool for targeting all TGF-ß isoforms in the TME.
Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Neoplasias de la Boca/tratamiento farmacológico , Neovascularización Patológica/tratamiento farmacológico , Receptores Fc/genética , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Animales , Carcinoma de Células Escamosas/metabolismo , Células HEK293 , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias de la Boca/metabolismo , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/metabolismo , Receptores Fc/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/uso terapéutico , Factor de Crecimiento Transformador beta/metabolismo , Microambiente TumoralRESUMEN
BACKGROUND AND AIM: There are only a few reports of non-Helicobacter pylori Helicobacter (NHPH) gastritis in Japanese patients. We aimed to examine its prevalence, clinical features, and esophagogastroduodenoscopy (EGD) findings based on 50 patients encountered in one facility. MATERIALS AND METHODS: Subjects were all patients who had undergone gastric mucosal biopsy endoscopically at Kenwakai Hospital for approximately 10 years. NHPH infection was diagnosed by microscopic findings of Giemsa staining performed on all specimens. PCR analysis of urease genes was performed to detect and identify NHPH, when informed consent was obtained. Helicobacter pylori-diagnostic tests were also performed. NHPH-infected patients were questioned about symptoms and animal contact. RESULTS: NHPH gastritis was found in 50 of 3847 patients (1.30%). The percentage increased to 3.35% (30 of 896 patients) in the latter 2 years and 4 months with increasing recognition of its characteristic endoscopic findings by endoscopists. PCR analysis, performed in 30 patients, detected NHPH in 28 patients: 26 as Helicobacter suis and 2 as Helicobacter heilmanii/Helicobacter ailurogastricus. Helicobacter pylori-diagnostic tests were almost negative. However, anti-H. pylori antibody showed high-negative titer (3.0-9.9 U/ml) in 12. Of 50 patients (consisting of 49 men and 1 woman), almost all were asymptomatic, and 25 were keeping pets. Regarding EGD findings, in all 50 patients, "crack-like mucosa" and/or nodular gastritis was noted in gastric antrum, and regular arrangement of collecting venules (RAC) was noted in gastric corpus. None of the patients infected with NHPH were co-infected with H. pylori. CONCLUSIONS: The prevalence was finally estimated to be approximately 3.35%. Helicobacter suis was the most common NHPH species. "Crack-like mucosa" and/or nodular gastritis in gastric antrum, RAC in gastric corpus, and H. pylori-negativity by H. pylori-diagnostic tests especially containing a high-negative titer of anti-H. pylori antibody may indicate NHPH infection.
Asunto(s)
Infecciones por Helicobacter , Helicobacter pylori , Animales , Femenino , Mucosa Gástrica , Gastroscopía , Helicobacter , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/epidemiología , Helicobacter pylori/genética , Humanos , Japón/epidemiología , Masculino , PrevalenciaRESUMEN
BACKGROUND: Non-Helicobacter pylori Helicobacter (NHPH) is not widely recognized as a cause of acute gastric mucosal lesions (AGML), as only a few cases of AGML caused by NHPH have been reported. We present here one case and examine the species and eradication of NHPH together with the three previously reported cases. CASE PRESENTATION: A 52-year-old woman presented with a two-day history of severe epigastric pain, nausea, and vomiting. An esophagogastroduodenoscopy showed mucosal edema, multiple erosions, and ulcerations in the antrum. Biopsy specimens taken from the antrum revealed long spiral-shaped organisms, suggesting NHPH. As both serum anti-Helicobacter pylori (H. pylori) antibody and H. pylori stool antigen test were negative, this case was diagnosed as AGML caused by NHPH. After the administration of esomeprazole 20 mg for 14 days and the interval of the following 12 days, AGML was deemed to have been cured endoscopically. In addition, microscopic examination and PCR analysis confirmed the success of NHPH eradication. CONCLUSIONS: NHPH should be considered a probable cause of AGML in cases that are not attributed to the other causes already recognized. Taking probability of spontaneous eradication into consideration, it is appropriate to start eradication therapy after confirming the chronicity of NHPH infection.
Asunto(s)
Gastritis , Infecciones por Helicobacter , Helicobacter , Enfermedad Aguda , Esomeprazol , Femenino , Mucosa Gástrica , Gastritis/diagnóstico , Gastritis/tratamiento farmacológico , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Humanos , Persona de Mediana EdadRESUMEN
Mutant activin receptor-like kinase-2 (ALK2) is associated with the pathogenesis of fibrodysplasia ossificans progressiva, making it an attractive target for therapeutic intervention. We synthesized a new series of bicyclic pyrazoles and evaluated their mutant ALK2 enzyme inhibitory activities, leading to the identification of 8 as the most potent inhibitor. This compound showed moderate microsomal metabolic stability and human ether-a-go-go related gene (hERG) safety. In C2C12 cells carrying mutant ALK2 (R206H), 8 efficiently inhibited the bone morphogenetic protein (BMP)-induced alkaline phosphatase activity.
Asunto(s)
Receptores de Activinas Tipo I/antagonistas & inhibidores , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Miositis Osificante/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/farmacología , Receptores de Activinas Tipo I/genética , Receptores de Activinas Tipo I/metabolismo , Animales , Compuestos Bicíclicos Heterocíclicos con Puentes/síntesis química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Línea Celular , Relación Dosis-Respuesta a Droga , Humanos , Ratones , Estructura Molecular , Mutación , Miositis Osificante/metabolismo , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Pirazoles/síntesis química , Pirazoles/química , Relación Estructura-ActividadRESUMEN
A carbon dioxide-dependent small-colony variant of Escherichia coli SH4888 was isolated from blood cultures of a patient with cholangitis. To date, little is known regarding the molecular mechanisms leading to formation of carbon dioxide-dependent phenotypes in clinical isolates, but abnormalities in the carbonic anhydrase are thought to cause carbon dioxide autotrophy. In this study DNA sequence analysis of the carbonic anhydrase-encoding can locus in the carbon dioxide-dependent E. coli SH4888 revealed that the isolate had a 325-bp deletion spanning from the 3'-terminal region of can to the 3'-terminal region of hpt, which encodes a hypoxanthine phosphoribosyltransferase. To confirm that the carbon dioxide-dependent SCV phenotype of E. coli SH4888 was due to the can mutation, we performed a complementation test with a plasmid carrying an intact can that restored the normal phenotype. However, E. coli SH4888 had increased virulence compared to the can-complemented E. coli SH4888 in a murine infection model. In conclusion, these data confirm that impaired carbonic anhydrase function can cause a carbon dioxide-dependent SCV phenotype in E. coli SH4888 and provides a fitness advantage in terms of infection.
Asunto(s)
Dióxido de Carbono/metabolismo , Anhidrasas Carbónicas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Anciano , Animales , Cultivo de Sangre , Colangitis/microbiología , Farmacorresistencia Bacteriana , Genes Bacterianos , Prueba de Complementación Genética , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Viabilidad Microbiana/genética , Mutación , Análisis de Secuencia de ADNRESUMEN
Thymidine-dependent small-colony variant (TD-SCV) of Escherichia coli was isolated from urine of a septuagenarian female patient on hemodialysis suffering from recurrent cystitis. The patient had been treated with frequent administrations of trimethoprim sulfamethoxazole (SXT), every time her cystitis symptoms developed. In the TD-SCV isolate, the deletion was detected in the thyA gene associated with thymidylate synthase. Interestingly, the isolate was found to produce extended-spectrum ß-lactamase (ESBL), and the experiment on conjugational transfer of the resistance trait was successful. By means of genetic analysis, the isolate was found to carry blaCTX-M-1 group. To the best of our knowledge, this is the first report of urinary tract infection caused by the transmissible ESBL-producing TD-SCV of E. coli. MICs of the TD-SCV were obtained only on the Mueller Hinton agar media supplemented with appropriate concentrations of thymidine, which might lead to the difficulty for proper chemotherapy in daily medicine. Furthermore, transmission of the ESBL gene via plasmid should be of concern.
Asunto(s)
Cistitis , Infecciones por Escherichia coli , Antibacterianos/uso terapéutico , Cistitis/tratamiento farmacológico , Escherichia coli/genética , Infecciones por Escherichia coli/tratamiento farmacológico , Femenino , Humanos , Timidina , beta-Lactamasas/genéticaRESUMEN
Mutant activin receptor-like kinase-2 (ALK2) was reported to be closely associated with the pathogenesis of fibrodysplasia ossificans progressiva (FOP) and diffuse intrinsic pontine glioma (DIPG), and therefore presents an attractive target for therapeutic intervention. Through in silico virtual screenings and structure-activity relationship studies assisted by X-ray crystallographic analyses, a novel series of bis-heteroaryl pyrazole was identified as potent inhibitors of ALK2 (R206H). Derived from in silico hit compound RK-59638 (6a), compound 18p was identified as a potent inhibitor of ALK2 (R206H) with good aqueous solubility, liver microsomal stability, and oral bioavailability.
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Receptores de Activinas Tipo I/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Pirazoles/farmacología , Administración Oral , Animales , Área Bajo la Curva , Disponibilidad Biológica , Simulación por Computador , Cristalografía por Rayos X , Semivida , Humanos , Microsomas Hepáticos/efectos de los fármacos , Estructura Molecular , Miositis Osificante/enzimología , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacocinética , Espectroscopía de Protones por Resonancia Magnética , Pirazoles/administración & dosificación , Pirazoles/química , Pirazoles/farmacocinética , Solubilidad , Espectrometría de Masa por Ionización de Electrospray , Relación Estructura-ActividadRESUMEN
BACKGROUND: Non-Helicobacter pylori helicobacters (NHPHs) besides H. pylori infect human stomachs and cause chronic gastritis and mucosa-associated lymphoid tissue lymphoma. Cholesteryl-α-glucosides have been identified as unique glycolipids present in H. pylori and some Helicobacter species. Cholesterol-α-glucosyltransferase (αCgT), a key enzyme for the biosynthesis of cholesteryl-α-glucosides, plays crucial roles in the pathogenicity of H. pylori. Therefore, it is important to examine αCgTs of NHPHs. MATERIALS AND METHODS: Six gastric NHPHs were isolated from Japanese patients and maintained in mouse stomachs. The αCgT genes were amplified by PCR and inverse PCR. We retrieved the αCgT genes of other Helicobacter species by BLAST searches in GenBank. RESULTS: αCgT genes were present in most Helicobacter species and in all Japanese isolates examined. However, we could find no candidate gene for αCgT in the whole genome of Helicobacter cinaedi and several enterohepatic species. Phylogenic analysis demonstrated that the αCgT genes of all Japanese isolates show high similarities to that of a zoonotic group of gastric NHPHs including Helicobacter suis, Helicobacter heilmannii, and Helicobacter ailurogastricus. Of 6 Japanese isolates, the αCgT genes of 4 isolates were identical to that of H. suis, and that of another 2 isolates were similar to that of H. heilmannii and H. ailurogastricus. CONCLUSIONS: All gastric NHPHs examined showed presence of αCgT genes, indicating that αCgT may be beneficial for these helicobacters to infect human and possibly animal stomachs. Our study indicated that NHPHs could be classified into 2 groups, NHPHs with αCgT genes and NHPHs without αCgT genes.
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Glucosiltransferasas/genética , Infecciones por Helicobacter/microbiología , Helicobacter/enzimología , Helicobacter/genética , Linfoma de Células B de la Zona Marginal/microbiología , Animales , Femenino , Gastritis/microbiología , Gastritis/patología , Genoma Bacteriano/genética , Helicobacter/clasificación , Infecciones por Helicobacter/patología , Humanos , Japón , Linfoma de Células B de la Zona Marginal/patología , Ratones , Datos de Secuencia Molecular , Filogenia , Reacción en Cadena de la Polimerasa , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Virulencia/genéticaRESUMEN
We here report a case of Dysgonomonas mossii bacteremia with cholangitis. An 85-year-old male patient with recurrent hepatitis B surface antigen-negative/anti-hepatitis C virus-negative hepatocellular carcinoma came to our hospital in poor physical condition. Two sets of blood cultures revealed a positive result for D. mossii. As matrix-assisted laser desorption/ionization time-of-flight mass spectrometry failed to identify D. mossii, analysis of 16S rRNA gene sequencing was performed; however, this gene is not specific enough to distinguish between D. mossii and D. oryzarvi. Finally, D. mossii infection was confirmed by gyrB and recA sequencing. To our knowledge, this is the first report of D. mossii causing human infection, which was identified in culture and confirmed using a combination of 16S rRNA, gyrB, and recA sequencing.
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Bacteriemia/microbiología , Infecciones Bacterianas/microbiología , Bacteroidetes/aislamiento & purificación , Anciano de 80 o más Años , Bacteriemia/diagnóstico , Infecciones Bacterianas/diagnóstico , Bacteroidetes/química , Bacteroidetes/genética , Humanos , Masculino , Espectrometría de Masa por Láser de Matriz Asistida de Ionización DesorciónRESUMEN
Helicobacter suis (H. suis), formerly called Helicobacter heilmannii type 1 (H. heilmannii), is a gram-negative bacterium of the Helicobacter species. This pathogen infects the stomach of humans and animals such as dogs, cats, pigs, and rodents, the latter giving rise to zoonotic infection. Here, we generated a H. suis-specific antibody useful for immunohistochemistry with formalin-fixed, paraffin-embedded tissue sections. To do so, we began by cloning the gene encoding H. suis cholesterol α-glucosyltransferase (αCgT). αCgT is the key enzyme responsible for biosynthesis of cholesteryl α-D-glucopyranoside (CGL), a major cell wall component of Helicobacter species including H. suis. The deduced amino acid sequence of H. suis αCgT had 56% identity with the corresponding Helicobacter pylori (H. pylori). We then developed a polyclonal antibody (anti-Hh-I205R) by immunizing rabbits with a 205 amino acid H. suis αCgT fragment. Immunohistochemistry with the anti-Hh-I205R antibody could differentiate H. suis from H. pylori in gastric mucosa sections derived from mice infected with either pathogen. We then probed formalin-fixed, paraffin-embedded sections of human gastric mucosa positive for H. suis infection with the anti-Hh-I205R antibody and detected positive staining. These results indicate that anti-Hh-I205R antibody is specific for H. suis αCgT and useful to detect H. suis in gastric specimens routinely analyzed in pathological examinations.