A 74-year-old man was admitted to our hospital to undergo an operation for distal aortic arch aneurysm with chronic aortic dissection. The first operation was attempted through left lateral thoracotomy. Since the aorta had a severely calcified false lumen, conventional aortic replacement was considered to entail greater risk and graft replacement was given up. As an another option, endovascular stent grafting via the aortic arch through median sternotomy was selected as a second operation. Deep hypothermic circulatory arrest with selective cerebral perfusion was used during delivery and deployment of the stented graft through the aortotomy site. The distal stented graft was deployed into the true lumen at the ninth thoracic vertebral level. Neither endoleaks nor complications were observed. Postoperative computed tomography showed complete thrombosis of the distal aortic arch aneurysm and the false lumen. The postoperative course was uneventful. Transaortic endovascular stent grafting is an effective and less invasive treatment for aortic arch aneurysms with severely calcified aorta.

With the progressive aging of the Japanese population, cardiac surgeons are increasingly faced with elderly patients. We have studied 29 consecutive patients, 80 years of age or older, who underwent aortic valve replacement at our institution between January 2000 and December 2003. Mortality, morbidity and late follow-up results were compared to those in 36 patients aged from 64 to 75 years old undergoing the same procedure over the same time period. The older patient group had a significantly higher incidence of calcified aortic stenosis and emergency operations and a higher score of NYHA functional class. Hospital mortality was 2 of 29 (6.9%) in the older patient group and 2 of 36 (5.6%) in the control group (ns). Postoperative renal failure and respiratory failure which needed prolonged ventilator support occured significantly more often in the older patient group. However, there was no significant difference between the 2 groups in terms of hospital stay. Almost all octogenarians showed improved NYHA functional class to class I or II after the operations. The actuarial survival rate was 89% in the older patient group and 78% in the control group at 3 years. The late survival rate and cardiac event-free rate were not significantly different between these 2 groups. Following aortic valve replacement, octogenarians, despite more compromised pre-operative status had good relief of symptoms, a favorable quality of life and a similar late survival to the younger patient groups. These findings support the recommendation that valve replacement should be performed in octogenarians with symptomatic aortic valvular disease.

Background: Comparative analysis of virulence factors (VFs) between Pasteurella canis and Pasteurella multocida are lacking, although both cause zoonotic infections. We determined the virulence-associated genome sequence characteristics of P. canis and assessed the toxin gene prevalence unique to P. canis among clinical isolates of P. canis and P. multocida. Methods: We selected 10 P. canis and 16 P. multocida whole-genome sequences (WGSs) from the National Center for Biotechnology database. The VFanalyzer tool was used to estimate P. canis-characteristic VFs. Amino acid sequences of VFs were compared with multiple-aligned sequences. The genome structure containing P. canis-characteristic and adjacent loci was compared to the corresponding P. multocida genome structure. After designing primer sequences and assessing their accuracy, we examined the gene prevalence of the P. canis-characteristic VFs using PCR among clinical isolates of P. multocida and P. canis. Results: Using VFanalyzer, we found virulence-associated cytolethal distending toxin (cdt)A–cdtB–cdtC loci common to all P. canis WGSs that were not found in P. multocida WGSs. Similarities in the multiple alignments of CdtA–CdtB–CdtC amino acid sequences were found among the 10 P. canis WGSs. Shared or similar loci around cdtA–cdtB–cdtC were identified between the P. canis and P. multocida genome structures. The PCR-based cdtA–cdtB–cdtC prevalence differed for P. canis and P. multocida clinical isolates. Conclusions P. canis-specific cdtA–cdtB–cdtC prevalence was identified among clinical isolates. These three loci may be unique toxin genes and promising targets for the rapid identification of P. canis in clinical settings.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a new zoonotic agent that emerged in December 2019, causes coronavirus disease 2019 (COVID-19). This infection can be spread by asymptomatic, presymptomatic, and symptomatic carriers. SARS-CoV-2 spreads primarily via respiratory droplets during close person-to-person contact in a closed space, especially a building. This article summarizes the environmental factors involved in SARS-CoV-2 transmission, including a strategy to prevent SARS-CoV-2 transmission in a building environment. SARS-CoV-2 can persist on surfaces of fomites for at least 3 days depending on the conditions. If SARS-CoV-2 is aerosolized intentionally, it is stable for at least several hours. SARS-CoV-2 is inactivated rapidly on surfaces with sunlight. Close-contact aerosol transmission through smaller aerosolized particles is likely to be combined with respiratory droplets and contact transmission in a confined, crowded, and poorly ventilated indoor environment, as suggested by some cluster cases. Although evidence of the effect of aerosol transmission is limited and uncertainty remains, adequate preventive measures to control indoor environmental quality are required, based on a precautionary approach, because COVID-19 has caused serious global damages to public health, community, and the social economy. The expert panel for COVID-19 in Japan has focused on the "3 Cs," namely, "closed spaces with poor ventilation," "crowded spaces with many people," and "close contact." In addition, the Ministry of Health, Labour and Welfare of Japan has been recommending adequate ventilation in all closed spaces in accordance with the existing standards of the Law for Maintenance of Sanitation in Buildings as one of the initial political actions to prevent the spread of COVID-19. However, specific standards for indoor environmental quality control have not been recommended and many scientific uncertainties remain regarding the infection dynamics and mode of SARS-CoV-2 transmission in closed indoor spaces. Further research and evaluation are required regarding the effect and role of indoor environmental quality control, especially ventilation.
Aerosols ; Air Pollution, Indoor/prevention & control* ; Betacoronavirus/physiology* ; COVID-19 ; Coronavirus Infections/transmission* ; Crowding ; Environment, Controlled ; Humans ; Pandemics/prevention & control* ; Pneumonia, Viral/transmission* ; SARS-CoV-2 ; Ventilation