MgADP inhibition, which is considered as a part of the regulatory system of ATP synthase, is a well-known process common to all F1-ATPases, a soluble component of ATP synthase. The entrapment of inhibitory MgADP at catalytic sites terminates catalysis. Regulation by the ε subunit is a common mechanism among F1-ATPases from bacteria and plants. The relationship between these two forms of regulatory mechanisms is obscure because it is difficult to distinguish which is active at a particular moment. Here, using F1-ATPase from Bacillus subtilis (BF1), which is strongly affected by MgADP inhibition, we can distinguish MgADP inhibition from regulation by the ε subunit. The ε subunit did not inhibit but activated BF1. We conclude that the ε subunit relieves BF1 from MgADP inhibition.

The diagnosis of viral pneumonia is often difficult because of its varied presentations. Regarding the serological diagnosis of viral infections, it is difficult to perform a viral DNA test in general medical facilities, especially in rural settings. Among viral pneumonia cases, herpes simplex virus (HSV) pneumonia can occur in immunocompromised hosts. However, when the clinical course of HSV pneumonia is acute, and the features of pneumonia are not distinct, the diagnosis can be challenging. We report the case of a 69year-old man who visited the hospital with complaints of dyspnea and cough for two days. Although the patient had no fever and the urine was negative for Legionella antigen, we suspected Legionella pneumonia based on the clinical course, Gram stain of sputum, and CT findings. After undergoing treatment with antibiotics, his condition worsened, with dyspnea and an increase in the demand for oxygen at 5 L. The patient also had complications related to the heart and liver. The sputum culture was negative, and the HSV serum test revealed that HSV IgM level was elevated to 1.16 (reference value: ≤0.80) and IgG level at admission and at follow-up 21 days later was elevated to 28.1 and 60.0 respectively (reference value: ≤2.0); accordingly, the patient was diagnosed with HSV pneumonia. In cases of pneumonia with atypical courses, the coexistence of multiple diseases, and immunosuppression, HSV pneumonia should be included in the differential diagnosis. In rural settings, viral pneumonia should be investigated using antibodies against viruses due to the limited availability of other medical resources. When a patient is judged to be immunosuppressed in the treatment of pneumonia of unknown cause, it is important to consider the possibility of HSV infection and take prompt action. Furthermore, it is essential to consider the possibility of multi-organ failure secondary to HSV infection, which requires systemic management.

No abstract

Infective endocarditis (IE) is caused by vegetations, consisting of platelets, fibrin, inflammatory cells, and microcolonies of bacteria, fungi, rickettsia, chlamydia, and viruses, that form in the heart valves, endocardium, and large vessel intima. Staphylococcus aureus endocarditis is highly tissue destructive, usually follows an acute course, and tends to become severe due to valve destruction, surrounding abscesses, and distant seeding. The main complications of IE due to S. aureus are heart failure due to destruction of tendon cords and valves, perivalvular abscesses and fistulas, and the dissemination of septic emboli to various organs including the brain, kidney, spleen, and lungs. The most common deep tissue abscess formed is an iliopsoas abscess; however, a few publications have described the formation of superficial muscle abscesses due to S. aureus bacteremia. For muscles near joints, deposition of calcium pyrophosphate crystals, as seen in pseudogout, can lead to pseudo-abscess formation and increase susceptibility to infection. This has been previously recognized in the iliopsoas muscle, in particular. We report a case of IE and intercostal muscle abscesses caused by S. aureus bacteremia in an 86-year-old man. Careful follow-up is required in patients with IE, due to the possibility of abscess formation. Furthermore, calcium pyrophosphate deposition in muscles around joints can trigger abscess formation when there is concurrent bloodstream infection.

In an aged society, the deterioration of physical and cognitive functions is prevalent. To motivate the rehabilitation of older persons, an initiative known as “shopping rehabilitation” incorporates shopping as an element of a nudge. The purpose of this study was to clarify motor function changes and cognitive functions of participants during shopping rehabilitation, through a semi-experimental study. We measured changes in the Kihon Checklist score before and after rehabilitation interventions. A paired t-test was used to analyze changes in the overall score of the basic checklist before and after the rehabilitation intervention. In December 2020, 59 participants answered the Kihon Checklist after their shopping rehabilitation intervention. During the 6-month intervention period, the number of participants with a checklist score of 8 or higher was significantly reduced after the intervention (p = 0.050). In the sub-analysis, the score improved significantly for the group with families (p = 0.050). Improvement was observed in the group living alone, but the difference was not significant (p = 0.428). The shopping rehabilitation intervention improved the Kihon Checklist score. Continuous observations and research are necessary to measure the long-term effects of shopping rehabilitation and the mechanisms that foster their maintenance and effects.