Endocarditis induced by M. morganii in an immunocompetent patient without underlying valvular abnormalities.

Background: The gram-positive cocci is the most common pathogens of infective endocarditis (IE), and it is rarely induced by gram negative bacteria. Only one prior case has been described, in which a patient reported with IE caused by M. morganii, who suffered from multiple myeloma and received high dosages of corticosteroids, chemotherapy and immunomodulatory agents. IE is seldom diagnosed in patients without underlying valvular abnormalities. The most important risk factors of IE are intravenous drug abuse, implanted foreign material and central venous catheterization. Case summary: We describe a case of 34-year-old patient presented to the hospital with recurrent fever and pneumonia since 5 months. He was diagnosed with infective endocarditis with tricuspid vegetation by transthoracic echocardiography (TTE). Two blood culture tests demonstrated the growth of M. morganii, which was further confirmed by a NGS test, as well as a culture of vegetation from the tricuspid. All the evidence confirmed that M. morganii was the causative pathogen of the endocarditis in this case. The IE in an immunocompetent patient without underlying valvular abnormalities had been cured with broad antibiotic therapy and surgical intervention. Conclusion: This was a unique case of IE induced by an extremely rare agent in an immunocompetent patient without underlying valvular abnormalities. Broad-antibiotics with ß-lactam enzyme inhibition should be used on time for M. morganii induced IE with bacteraemia. The operation to curette the vegetation and repair the tricuspid was also an important way to cure the endocarditis in the patient without underlying valvular abnormalities and with repeated episodes of blood stream and lung infections.

Surface engineering of hematite nanorods photoanode towards optimized photoelectrochemical water splitting.

Rapid charge recombination in hematite (Fe2O3) during photoelectrochemical water splitting is a major obstacle to achieving high-efficiency photoelectrodes. Surface defect engineering is considered as a viable strategy for enhancing photoelectrochemical activity of oxide photoanodes. Herein, a one-dimensional (1D) defective γ-Fe2O3 nanorods (DFNRs) photoanode is prepared using solvothermal and high-temperature hydrogenation strategies. The as-prepared DFNRs possess superior visible-light absorption capacity and exhibit excellent photoelectrochemical performance (0.98 mA cm-2), with approximately three-fold higher photocurrent density than that of pristine Fe2O3 (FNRs, 0.32 mA cm-2). The enhanced activity of the DFNRs results from the moderate formation of oxygen vacancy defects, which promotes spatial charge separation and transfer at the DFNRs/electrolyte interface, as well as the 1D nanorod structure, which favors rapid charge transfer. The surface of γ-Fe2O3 with hydroxyl (OH) groups provides sufficient surface-active sites. This result suggests that surface-oxygen deficiency of γ-Fe2O3 can not only expand the light absorption range but also facilitating photo-generated charge carriers separation. This surface engineering strategy provides an alternative method for preparing stable and highly active metal oxide photoanodes for photoelectrochemical water splitting.

Efficient Charge Transfer Channels in Reduced Graphene Oxide/Mesoporous TiO2 Nanotube Heterojunction Assemblies toward Optimized Photocatalytic Hydrogen Evolution.

Interface engineering is usually considered to be an efficient strategy to promote the separation and migration of photoexcited electron-hole pairs and improve photocatalytic performance. Herein, reduced graphene oxide/mesoporous titanium dioxide nanotube heterojunction assemblies (rGO/TiO2) are fabricated via a facile hydrothermal method. The rGO is anchored on the surface of TiO2 nanosheet assembled nanotubes in a tightly manner due to the laminated effect, in which the formed heterojunction interface becomes efficient charge transfer channels to boost the photocatalytic performance. The resultant rGO/TiO2 heterojunction assemblies extend the photoresponse to the visible light region and exhibit an excellent photocatalytic hydrogen production rate of 932.9 µmol h-1 g-1 under simulated sunlight (AM 1.5G), which is much higher than that of pristine TiO2 nanotubes (768.4 µmol h-1 g-1). The enhancement can be ascribed to the formation of a heterojunction assembly, establishing effective charge transfer channels and favoring spatial charge separation, the introduced rGO acting as an electron acceptor and the two-dimensional mesoporous nanosheets structure supplying a large surface area and adequate surface active sites. This heterojunction assembly will have potential applications in energy fields.