Changes in excitation relaxation of diatoms in response to fluctuating light, probed by fluorescence spectroscopies.

A marine pennate diatom Phaeodactylum tricornutum (Pt) and a marine centric diatom Chaetoceros gracilis (Cg) possess unique light-harvesting complexes, fucoxanthin chlorophyll a/c-binding proteins (FCPs). FCPs have dual functions: light harvesting in the blue to green regions and quenching of excess energy. So far, excitation dynamics including FCPs have been studied by altering continuous light conditions. In the present study, we examined responses of the diatom cells to fluctuating light (FL) conditions. Excitation dynamics in the cells incubated under the FL conditions were analyzed by time-resolved fluorescence measurements followed by global analysis. As responses common to the Pt and Cg cells, quenching behaviors were observed in photosystem (PS) II with time constants of hundreds of picoseconds. The PSII → PSI energy transfer was modified only in the Pt cells, whereas quenching in FCPs was suggested only in the Cg cells, indicating different strategy for the dissipation of excess energy under the FL conditions.

[Anesthetic management of organ donation after brain death using continuous total hemoglobin measurement].

A 60-year-old woman declared brain dead was scheduled for organ donation. We continuously measured total hemoglobin values (SpHb) using a Radical-7 monitor (Masimo Co, Irvine, CA, USA) to maintain the functions of organs and oxygen delivery. At the start of surgery, the SpHb value was 9.3 g x dl(-1). Packed red blood cells were transfused immediately No anesthetics or opioids were used during the operation. Blood pressure suddenly decreased to below 80 mmHg because of bleeding, manipulation of organs, and/or compression of the vena cava. Six units of red blood cells and 900 ml of colloids were rapidly transfused with real-time monitoring of SpHb values. On cross-clamping of the aorta, the SpHb value increased up to 10.2 g x dl(-1). The heart, lungs, liver, pancreas, and kidneys were donated from the patient without organ dysfunction. The highlight of this case report is that anesthesiologists could use SpHb monitoring for management of hemodynamics in a brain-dead organ donor.

Exophiala dermatitidis coinfection with nontuberculous mycobacteria: A case report and literature review.

Six years ago, a 60-year-old man presented to our hospital with a cough and sputum. Upon suspicion of nontuberculous mycobacterial (NTM) infection, he was followed up at our hospital. Because the abnormal shadows in the bilateral lung fields deteriorated slightly over 6 years, bronchoscopy was performed. Exophiala dermatitidis and Mycobacterium intracellulare were detected in the bronchial lavage fluid. The patient underwent follow-up examinations without drug administration. Currently, the patient's condition remains stable. E. dermatitidis is regulatory found in the lungs of patients with cystic fibrosis, but only rarely is it found in respiratory samples from patients without cystic fibrosis. However, NTM complications have been reported more frequently in recent years. Due to the increasing number of NTM patients, E. dermatitidis pulmonary infections may also increase. Additional research is required to develop strategies for treating this infection.