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Changes in the gut microbiome have pivotal roles in the pathogenesis of acute graft-versus-host disease (aGVHD) after allogenic haematopoietic cell transplantation (allo-HCT)1-6. However, effective methods for safely resolving gut dysbiosis have not yet been established. An expansion of the pathogen Enterococcus faecalis in the intestine, associated with dysbiosis, has been shown to be a risk factor for aGVHD7-10. Here we analyse the intestinal microbiome of patients with allo-HCT, and find that E. faecalis escapes elimination and proliferates in the intestine by forming biofilms, rather than by acquiring drug-resistance genes. We isolated cytolysin-positive highly pathogenic E. faecalis from faecal samples and identified an anti-E. faecalis enzyme derived from E. faecalis-specific bacteriophages by analysing bacterial whole-genome sequencing data. The antibacterial enzyme had lytic activity against the biofilm of E. faecalis in vitro and in vivo. Furthermore, in aGVHD-induced gnotobiotic mice that were colonized with E. faecalis or with patient faecal samples characterized by the domination of Enterococcus, levels of intestinal cytolysin-positive E. faecalis were decreased and survival was significantly increased in the group that was treated with the E. faecalis-specific enzyme, compared with controls. Thus, administration of a phage-derived antibacterial enzyme that is specific to biofilm-forming pathogenic E. faecalis-which is difficult to eliminate with existing antibiotics-might provide an approach to protect against aGVHD.
Assuntos
Bacteriófagos , Enterococcus faecalis , Microbioma Gastrointestinal , Doença Enxerto-Hospedeiro , Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Adulto Jovem , Bacteriófagos/enzimologia , Bacteriófagos/genética , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Disbiose/complicações , Disbiose/microbiologia , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/crescimento & desenvolvimento , Enterococcus faecalis/metabolismo , Enterococcus faecalis/virologia , Fezes/microbiologia , Vida Livre de Germes , Doença Enxerto-Hospedeiro/complicações , Doença Enxerto-Hospedeiro/microbiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Doença Enxerto-Hospedeiro/terapia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Técnicas In Vitro , Intestinos/efeitos dos fármacos , Intestinos/microbiologia , Perforina/metabolismo , Fatores de Risco , Transplante Homólogo/efeitos adversos , Sequenciamento Completo do Genoma , Farmacorresistência Bacteriana/efeitos dos fármacos , Antibacterianos/farmacologiaRESUMO
OBJECTIVES: Clostridioides difficile infection (CDI) often recurs. Approximately 25% of patients have recurrences after the initial treatment, and patients who have relapsed once are more likely to relapse. We aimed to identify the risk factors for initial CDI recurrence. METHODS: We performed a retrospective survey of patient backgrounds and treatment-related factors. Risk factors were analyzed using single and multiple logistic regression analyses. RESULTS: A total of 134 patients were included in the study. Prophylactic probiotic use and nasogastric tube feeding were independent risk factors for the initial recurrence of CDI. Patients using prophylactic probiotics had significantly higher recurrence rates than those not using prophylactic probiotics. CONCLUSION: Prophylactic probiotic use and nasogastric tube placement may be risk factors for the initial recurrence of CDI. It is noteworthy that CDI that occurs during the use of prophylactic probiotics may be prone to recurrence.
Assuntos
Clostridioides difficile , Infecções por Clostridium , Probióticos , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/prevenção & controle , Humanos , Probióticos/uso terapêutico , Recidiva , Estudos Retrospectivos , Fatores de RiscoRESUMO
INTRODUCTION: Solithromycin is a novel fluoroketolide developed to treat pneumonia. But, few studies evaluating its antimicrobial activity against S. pneumoniae in a mixed-infection model with anaerobes are available, while community-acquired pneumonia can involve mixed-infection of Streptococcus pneumoniae and anaerobic bacteria. This study evaluated the antimicrobial activity of solithromycin against macrolide-resistant S. pneumoniae and anaerobic bacteria with a murine pneumonia mixed-infection model. MATERIAL AND METHODS: We evaluated antimicrobial activity of solithromycin (10 and 20 mg/kg) and levofloxacin (126 mg/kg) against S. pneumoniae with a three-point mutation in penicillin-binding protein and an ermB gene, and Parvimonas micra. Antimicrobial efficacy was calculated for each isolate as the change in bacterial count (Δlog10 CFU/mL) obtained in the treated mice after 24 h compared with the count in the starting control animals. RESULTS: The solithromycin and levofloxacin minimum inhibitory concentrations (MICs) for S. pneumoniae were 0.03 and 0.5 µg/mL, respectively. The solithromycin and levofloxacin MICs for P. micra were 0.015 and 0.12 µg/mL, respectively. In a mixed-infection model, solithromycin showed significantly higher antimicrobial activity against S. pneumoniae than levofloxacin (solithromycin 20 mg/kg; -2.87 ± 1.33 log10 CFU/mL vs. levofloxacin; -1.35 ± 0.37 log10 CFU/mL, p = 0.0397). Similarly, solithromycin showed significantly higher antimicrobial activity against P. micra than levofloxacin (solithromycin 20 mg/kg; -2.78 ± 0.98 log10 CFU/mL vs. levofloxacin; -1.57 ± 0.47 log10 CFU/mL, p = 0.0400). DISCUSSION: Solithromycin showed higher antimicrobial activities against macrolide-resistant S. pneumoniae and P. micra than levofloxacin, even though they were coexisted in murine lung tissue. Our results suggest that solithromycin could be effective for pneumonia patients due to S. pneumoniae to reduce bacterial density in lung tissue.
Assuntos
Antibacterianos/uso terapêutico , Bactérias Anaeróbias/efeitos dos fármacos , Coinfecção/tratamento farmacológico , Levofloxacino/farmacologia , Macrolídeos/farmacologia , Streptococcus pneumoniae/efeitos dos fármacos , Triazóis/farmacologia , Animais , Antibacterianos/farmacologia , Bactérias Anaeróbias/patogenicidade , Coinfecção/microbiologia , Modelos Animais de Doenças , Farmacorresistência Bacteriana , Feminino , Humanos , Levofloxacino/uso terapêutico , Macrolídeos/uso terapêutico , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Organismos Livres de Patógenos Específicos , Streptococcus pneumoniae/patogenicidade , Resultado do Tratamento , Triazóis/uso terapêuticoRESUMO
The regioselective alkenylation at the ortho position of phenylphosphine sulfides using alkenes proceeds efficiently in the presence of a cationic Cp*-rhodium(III) catalyst and an appropriate oxidant. A similar rhodium catalyst also promotes the redox-neutral coupling of the phosphine sulfides with alkynes to afford ortho-alkenylated products.
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The corrphycene mol-ecule of the title compound, [Cu(C(36)H(36)N(4)O(4))](0.034).0.966C(36)H(38)N(4)O(4), has an essentially planar macrocyclic framwork with a slightly distorted trapezoidal N(4) core; the r.m.s. deviation of the peripheral 20â C atoms and four N atoms is 0.054â (3)â Å. The surface area within the N(4)-coordinating core (8.358â Å(2)) is significantly smaller than that (8.503â Å(2)) of the corresponding free-base porphyrin. Two intra-molecular N-Hâ¯N hydrogen bonds are observed. Detailed structure analysis clarified that the co-crystallization of the free-base corrphycene together with a quite minor component (ca 3%) of corrphycenato-Cu(II) occurred in the recrystallization process.
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BACKGROUND: Rheumatoid arthritis (RA) is a disease that can cause joint destruction and multiple arthritis. We retrospectively investigated bone and joint destruction during the perinatal period in adult patients with RA and juvenile idiopathic arthritis (JIA) in our hospitals in the last decade. METHODS: The study included 15 women, with 20 pregnancies, 19 childbirths, and one fetal death recorded between 2009 and 2018. We analyzed patient characteristics, disease activity, the modified total Sharp score (mTSS), and ΔmTSS from prepregnancy to delivery and from delivery to one year after delivery in the biologics (BIO) group (biologics used before pregnancy) and non-BIO group (not using biologics). RESULTS: There were five preterm births and seven low-birth-weight infants. The Clinical Disease Activity Index (CDAI) before pregnancy and postdelivery worsened from 12±1.8 to 19.9±2.7 (p<0.05). The mTSS at prepregnancy and postdelivery was 47.7±12.2 and 57.3±11.1 in the BIO group, respectively, and 58.9±11.9 and 75.0±13.1 in the non-BIO group, respectively. In addition, the ΔmTSS value from prepregnancy to delivery and from delivery to one year after delivery was 14.5±4.8 and 9.2±1.7 in the BIO group, respectively (p<0.05), and 16.1±5.2 and 8.3±4.0 in the non-BIO group, respectively. CONCLUSION: The disease activity worsened, and bone and joint destruction progressed in both the BIO and non-BIO groups during the perinatal period in adult patients with RA and JIA in the last decade.
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The title complex, [Fe(C(36)H(36)N(4)O(4))Cl], shows a domed structure with a slightly distorted trapezoidpyramidal core, in which the perpendicular displacements of the Fe(III) atom from the mean pyrrole N(4) plane are 0.418â (3) and 0.465â (3)â Å for the two crystallographically independent mol-ecules.
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Polyelectrolyte gels exhibit swelling behaviors that are dependent on the external environment. The swelling behaviors of highly charged polyelectrolyte gels can be well explained using the Flory-Rehner model combined with the Gibbs-Donnan effect and Manning's counterion condensation effect (the FRGDM model). This study investigated the swelling properties of a series of model polyelectrolyte gels, namely tetra-polyacrylic acid-polyethylene glycol gels (Tetra-PAA-PEG gels), and determined the applicability of the FRGDM model. The swelling ratio (Vs/V0) was well reproduced by the FRGDM model in the moderate swelling regime (Vs/V0 < 10). However, in the high swelling regime (Vs/V0 > 10), the FRGDM model is approx. 1.6 times larger than the experimental results. When we introduced the finite extensibility to the elastic free energy in the FRGDM model, the swelling behavior was successfully reproduced even in the high swelling regime. Our results reveal that finite extensibility is one of the factors determining the swelling equilibrium of highly charged polyelectrolyte gels. The modified FRGDM model reproduces well the swelling behavior of a wide range of polyelectrolyte gels.
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In recent years, microwave energy is expected to be a heat source of high temperature process aiming for CO2 reduction and energy conservation owing to the possibility of volumetric heating. In order to examine the applicability of microwave heating to ironmaking, it is important to investigate the microwave heating of raw materials of ironmaking such as Fe3O4. In this study, the effect of particle size and relative density on microwave absorptivity of powdery Fe3O4 was elucidated by the heating curves. Powdery Fe3O4 samples having different particle sizes and relative densities and bulk Fe3O4 samples were heated at the positions of the H (magnetic) and E (electric) field maxima in a 2.45 GHz single-mode microwave cavity. Sample temperatures abruptly increase and become constant after a while. At a constant temperature, the energy balance is attained, i.e., the rate of microwave energy absorption is equal to the rate of thermal energy dissipation. Assuming that the thermal energy dissipation rate due to convection and radiation heat fluxes is only a function of the sample temperature, the microwave absorptivity could be evaluated by the temperature at the steady state. It has been found that the microwave absorptivity of Fe3O4 powder decreases with an increase in relative density. On the other hand, the microwave absorptivity hardly depends on the particle size, which may be due to its quite a large penetration depth of Fe3O4 compared to metal.
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Community-acquired pneumonia (CAP) can involve mixed-species bacterial infection. However, few studies have investigated antimicrobial efficacy in the treatment of mixed species infections. This study aimed to compare the in vivo antimicrobial activity of garenoxacin (GRNX) and levofloxacin (LVFX) against Streptococcus pneumoniae and Parvimonas micra in a murine model of mixed species bacterial pneumonia. S. pneumoniae D-6888 and P. micra No. 242 were used in this study. Antimicrobial activity toward each isolate was calculated as the change in bacterial count in the lungs (Δlog10 CFU/mL) of mice after 24 h of treatment compared with the count in pretreated animals (0 h). The MICs of GRNX and LVFX against S. pneumoniae D-6888 were 0.06 and 0.5 mg/L and the MICs against P. micra No. 242 were 0.03 and 0.12 mg/L, respectively. In a murine pneumonia mixed-infection model, GRNX showed significantly higher in vivo antimicrobial activity against S. pneumoniae than LVFX (GRNX; ï¼2.02 ± 0.99 log10 CFU/mL vs. LVFX; ï¼0.97 ± 0.61 log10 CFU/mL, p = 0.0188). GRNX displayed about 2-fold more potent activity against P. micra than LVFX (GRNX; ï¼1.12 ± 0.56 log10 CFU/mL vs. LVFX; ï¼0.61 ± 0.43 log10 CFU/mL, p = 0.1029). These results suggest that GRNX is preferable for the treatment of mixed species bacterial CAP.
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Antibacterianos/uso terapêutico , Coinfecção/tratamento farmacológico , Fluoroquinolonas/uso terapêutico , Levofloxacino/uso terapêutico , Pneumonia Bacteriana/tratamento farmacológico , Animais , Coinfecção/microbiologia , Modelos Animais de Doenças , Feminino , Firmicutes , Camundongos Endogâmicos ICR , Neutropenia , Pneumonia Bacteriana/microbiologia , Organismos Livres de Patógenos Específicos , Streptococcus pneumoniaeRESUMO
The prevalence of type I allergic diseases such as food allergy and allergic rhinitis has increased. Therefore, many studies have focused on food factors with anti-allergic activities in recent years. In order to investigate the effect of food factors on mast cell activation, a RBL-2H3 cell monoculture system has been widely used, in which various food factors have been reported to inhibit degranulation of RBL-2H3 cells. However, some orally administered food factors do not interact directly with immune cells but do so indirectly through intestinal epithelial cells. In this report, we established a novel in vitro co-culture model to evaluate anti-allergic effects of orally administered food factors. The co-culture system, comprised of Caco-2 cells (apical component) and RBL-2H3 cells (basolateral component), was able to evaluate the effects of two flavonoids that are known to have the inhibitory effects on mast cell degranulation. Moreover, we evaluated the anti-allergic effects of Enterococcus faecalis strains that are not absorbed through the intestine. We identified two strains of lactic acid bacteria that had inhibitory effects on mast cell degranulation using this co-culture system and possessed anti-allergic properties in a passive cutaneous anaphylaxis model mouse. This novel in vitro co-culture model was applicable for finding food factors with anti-allergic effects and might be useful for examining its anti-allergic mechanisms.
Assuntos
Antialérgicos/farmacologia , Degranulação Celular , Técnicas de Cocultura , Flavonoides/farmacologia , Intestinos/imunologia , Anafilaxia Cutânea Passiva/imunologia , Alérgenos , Animais , Células CACO-2 , Linhagem Celular , Enterococcus faecalis/fisiologia , Alimentos , Hipersensibilidade Alimentar , Humanos , Quempferóis/farmacologia , Lactobacillus/isolamento & purificação , Lactobacillus/fisiologia , Luteolina/farmacologia , Mastócitos/fisiologia , Camundongos , RatosRESUMO
A new regioselective synthetic methodology for benzo[b]phosphole derivatives has been developed. Thus, a range of functionalized benzo[b]phosphole oxides could be synthesized via Rh(III)-catalyzed C-H alkenylation of arylthiophosphinamides with alkynes followed by formal phospha-Friedel-Crafts cyclization.
RESUMO
D-Aspartate (D-Asp), a free D-amino acid found in mammals, plays crucial roles in the central nervous, neuroendocrine, and endocrine systems. In mammalian tissues, D-Asp oxidase (DDO) is a degradative enzyme that stereospecifically acts on D-Asp. Asp racemase, a synthetic enzyme that produces D-Asp from L-Asp, has been identified in several lower organisms; however, the biosynthetic pathway of D-Asp in mammals remains to be fully clarified. The aim of this study was to establish a simple, accurate, and sensitive enzymatic method for the determination of Asp racemase activity. Using recombinant Streptococcus thermophilus Asp racemase as a model enzyme, two enzymatic methods for the determination of Asp racemase activity were optimized. In these methods, recombinant human DDO was used to degrade D-Asp formed from L-Asp by the Asp racemase reaction to 2-oxo acid, the amounts of which were then determined using a colorimetric assay. In one method, designated the coupling method, DDO was concomitantly included in the Asp racemase reaction mixture, and the Asp racemase reaction was readily coupled to the D-Asp degradative reaction by DDO during the incubation. In the other method, designated the separating method, an aliquot of the Asp racemase reaction mixture was mixed with DDO after the reaction to determine the amounts of D-Asp produced by Asp racemase. Under optimized conditions, the accuracy and sensitivity of these two methods were examined and compared, both to one another and conventional high-performance liquid chromatography (HPLC). The results presented here suggest that the coupling method is more accurate and sensitive than the other two methods and can be used for the determination of Asp racemase activity. The coupling method may help to advance our current understanding of the biosynthetic pathway of D-Asp in mammals.
Assuntos
Isomerases de Aminoácido/análise , Isomerases de Aminoácido/metabolismo , Ácido Aspártico/análise , Ácido Aspártico/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Ativação Enzimática/fisiologia , Humanos , Streptococcus thermophilus/enzimologiaRESUMO
The photo-hydrogen-evolving activity (activity to enhance the photochemical EDTA-reduction of water into molecular hydrogen) was evaluated for three different Ru(II)Pt(II) dimers with a general formula of [(bpy)2Ru(micro-bridge)PtCl2]2+(bpy = 2,2'-bipyridine; bridge = 4,4'-bis(N-(3-aminopropyl)carbamoyl)-2,2'-bipyridine (L1), 2,3-bis(2-pyridyl)pyrazine (L2), and 4,4'-bis(N-(4-pyridyl)methylcarbamoyl)-2,2'-bipyridine (L3); EDTA = ethylenediaminetetraacetic acid disodium salt). A new Ru(II)Pt(II) complex, [(bpy)2Ru(micro-L3)PtCl2]2+, was synthesized and characterized. It was confirmed that all three compounds are ineffective towards photochemical H2 production. In each case, an acetate-buffer solution (pH = 5) containing the Ru(II)Pt(II) dimer and EDTA was photolysed using a 350-W Xe lamp under an Ar atmosphere, during which the amount of H2 evolved was analysed by gas chromatography. Additional photolysis experiments were carried out by adding [Ru(bpy)3]2+ and methylviologen (N,N'-dimethyl-4,4'-bipyridinium) to the photolysis solutions described above to test the H2-evolving activity of the Pt(II) unit involved in these Ru(II)Pt(II) dimers. As a result, the Pt(II) units involved in the L1 and L2 compounds were found to be active as an H2-evolving catalyst, while that of the L3 compound was found to show no activity at all. The extent of intramolecular electron-transfer quenching from the 3MLCT excited state of the [Ru(bpy)3]2+ derivative to the tethering Pt(II) catalyst centre was investigated by comparison of the luminescence spectra of these compounds, together with the related compounds. The results showed that the quenching of the 3MLCT luminescence is not at all enhanced in either the L1 or the L3 compounds. On the other hand, the L2 compound is strongly quenched as previously reported. In addition to the above studies, the H2-evolving activity of some Pt(II) monomers, cis-PtCl2(NH3)2, PtCl2(en)(en = ethylenediamine), cis-PtCl2(4-methylpyridine)2, PtCl2(2,2'-bipyrimidine), PtCl2(4,4'-dicarboxy-2,2'-bipyridine), and [PtCl(terpy)]+(terpy = 2,2':6',2''-terpyridine), were similarly investigated in the presence of EDTA, [Ru(bpy)3]2+ and methylviologen, since they were regarded as structural analogues of the Pt(II) units involved in the L1-L3 compounds. The compounds having a cis-Pt(II)Cl2 unit were generally found to show high H2-evolving activity. This was interpreted in terms of the ligation of negatively charged chloride anions leading to the destabilization of the Pt(II) dz2 orbital responsible for the hydrogenic activation. Importantly, cis-PtCl2(4-methylpyridine)2 exhibited relatively high activity as an H2-evolving catalyst, suggesting the importance of the flexible rotation of the pyridyl ligands for efficient hydrogenic activation at the axial site of the Pt(II) ion. The DFT calculations also showed the validity of the structure-activity relationship discussed above for the L3 compound.