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11.
Atherosclerosis is initiated by adhesion and infiltration of inflammatory leukocytes into the intima, where non-receptor protein tyrosine kinases, such as focal adhesion kinase (FAK) and proline-rich tyrosine kinase 2 (PYK2), play important roles as intracellular messengers of mechanical and biochemical signals. In the present study, we examined whether FAK and PYK2 are up-regulated by elevated blood pressure or circulating humoral factors in hypertension. We used a rat model of abdominal aortic banding that allows separate evaluation of elevated blood pressure (upper body) and circulating humoral factors (lower body). We obtained the proximal and distal aortas of the banding site, 6 hours, 3 days, and 1 and 4 weeks after the banding procedure, for evaluation of phosphorylation of FAK and PYK2 by Western blotting. Arterial pressure was significantly elevated only in the upper body throughout the experimental period. The expression of FAK and the FAK phosphorylation were significantly increased at 1 and 4 weeks only in the proximal aorta. This was also the case for the expression of total PYK2 and the PYK2 phosphorylation. In contrast, there was no significant change in FAK or PYK2 phosphorylation in the distal aorta, whereas plasma levels of angiotensin II were systemically elevated. In sham-operated rats, no change in FAK or PYK2 phoshorylation was noted in the proximal and distal aortas. These results indicate that phosphorylation of FAK and PYK2 is upregulated by elevated blood pressure but not by humoral factors in the rat aorta, demonstrating novel aspects of atherogenesis in hypertension.  相似文献   
12.

Purpose

This study describes the use of CT images in atlas-based automated planning methods for acetabular cup implants in total hip arthroplasty (THA). The objective of this study is to develop an automated cup planning method considering the statistical distribution of the residual thickness.

Methods

From a number of past THA planning datasets, we construct two statistical atlases that represent the surgeon’s expertise. The first atlas is a pelvis-cup merged statistical shape model (PC-SSM), which encodes global spatial relationships between the patient anatomy and implant. The other is a statistical residual thickness map (SRTM) of the implant surface, which encodes local spatial constraints of the anatomy and implant. In addition to PC-SSM and SRTM, we utilized the minimum thickness as a threshold constraint to prevent penetration.

Results

The proposed method was applied to the pelvis shapes segmented from CT images of 37 datasets of osteoarthritis patients. Automated planning results with manual segmentation were compared to the plans prepared by an experienced surgeon. There was no significant difference in the average cup size error between the two methods (1.1 and 1.2 mm, respectively). The average positional error obtained by the proposed method, which integrates the two atlases, was significantly smaller (3.2 mm) than the previous method, which uses single atlas (3.9 mm). In the proposed method with automated segmentation, the size error of the proposed method for automated segmentation was comparable (1.1 mm) to that for manual segmentation (1.1 mm). The average positional error was significantly worse (4.2 mm) than that using manual segmentation (3.2 mm). If we only consider mildly diseased cases, however, there was no significance between them (3.2 mm in automated and 2.6 mm in manual segmentation).

Conclusion

We infer that integrating PC-SSM and SRTM is a useful approach for modeling experienced surgeon’s preference during cup planning.
  相似文献   
13.
A novel New Delhi metallo-β-lactamase, NDM-13, was identified in a carbapenem-resistant Escherichia coli clinical isolate obtained from the urine of a patient in Nepal. The enzymatic activity of NDM-13 against β-lactams was similar to that of NDM-1. However, NDM-13 displayed significantly higher kcat/Km ratios for cefotaxime. The genetic environment of blaNDM-13 was determined to be tnpA-IS30-blaNDM-13-bleMBL-trpF-dsbC-cutA-groES-groL, with blaNDM-13 located within the chromosome.  相似文献   
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This study aimed to measure the impact of the COVID-19 pandemic on the volumes of annual stroke admissions compared with those before the pandemic in Japan. We conducted an observational, retrospective nationwide survey across 542 primary stroke centers in Japan. The annual admission volumes for acute stroke within 7 days from onset between 2019 as the pre-pandemic period and 2020 as the pandemic period were compared as a whole and separately by months during which the epidemic was serious and prefectures of high numbers of infected persons. The number of stroke patients declined from 182,660 in 2019 to 178,083 in 2020, with a reduction rate of 2.51% (95% confidence interval [CI], 2.58%-2.44%). The reduction rates were 1.92% (95% CI, 1.85%-2.00%; 127,979-125,522) for ischemic stroke, 3.88% (95% CI, 3.70%-4.07%, 41,906-40,278) for intracerebral hemorrhage, and 4.58% (95% CI, 4.23%-4.95%; 13,020-12,424) for subarachnoid hemorrhage. The admission volume declined by 5.60% (95% CI, 5.46%-5.74%) during the 7 months of 2020 when the epidemic was serious, whereas it increased in the remaining 5 months (2.01%; 95% CI, 1.91%-2.11%). The annual decline in the admission volume was predominant in the five prefectures with the largest numbers of infected people per million population (4.72%; 95% CI, 4.53%-4.92%). In conclusion, the acute stroke admission volume declined by 2.51% in 2020 relative to 2019 in Japan, especially during the months of high infection, and in highly infected prefectures. Overwhelmed healthcare systems and infection control practices may have been associated with the decline in the stroke admission volume during the COVID-19 pandemic.  相似文献   
17.
Anastomotic complications of the coronary arteries were observed in approximately 5% of patients undergoing Bentall-type surgery. Given the high surgical risk of reoperation, percutaneous coronary intervention could be a treatment for anastomotic complications but is challenging because of the complicated anatomy after Bentall-type surgery. Here, a 70-year-old man underwent a Bentall operation during which the left main coronary artery was accidentally injured. Therefore, coronary artery bypass using a saphenous vein graft was performed. The saphenous vein graft was anastomosed from the right side of the aortic graft to the left main coronary artery. Three years later, the patient presented with an anterior non–ST-segment elevation myocardial infarction. Because his unusual anatomy, the saphenous vein graft could not be cannulated with diagnostic catheters, even after perusing the surgical record of the Bentall surgery. Subsequently, coronary computed tomography angiography was performed. Three-dimensional reconstructed images visualized the positional relationship between the saphenous vein graft and anatomical landmarks, such as the implanted surgical valve prosthesis. The angiogram angle was adjusted using these landmarks and projection angles estimated by the images. Then, the ASAHI Hyperion Judkins right 4 catheter could be easily inserted, and percutaneous coronary intervention was successfully performed. Three-dimensional reconstruction images were useful for performing percutaneous coronary intervention by aiding in the identification of the anatomic location of the saphenous vein graft and the positional relationship between the saphenous vein graft and anatomic landmarks. In patients with unusual anatomy, as in this case, coronary computed tomography angiography should be strongly considered.  相似文献   
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The novel coronavirus-19 (COVID-19) pandemic has considerably impacted children’s lives. The aim of this study was to determine whether the pandemic affected mealtime regularity among preschool children and whether maintaining regular mealtimes or changes in mealtime regularity during the pandemic were related to dietary balance, including chronological relationships. This online cross-sectional survey involving individuals registered with a company that provides meals to children aged 2−6 years was conducted in February 2021. Using a 40-point scale, a healthy diet score (HDS) was developed to evaluate children’s dietary balance. The participants were divided into four groups based on their responses, and multiple regression analyses were performed with the HDS as the dependent variable. Maintaining regular mealtimes was associated with practices such as waking and going to bed earlier, less snacking, and eating breakfast every day. Even after adjusting for basic attributes, lifestyle habits, household circumstances, and other factors, regular mealtimes were still positively correlated with the HDS. These findings indicate that maintaining regular mealtimes is associated with higher HDS scores and better lifestyle habits. Furthermore, as the changed HDS was higher in the group whose mealtimes became regular during the pandemic, adopting regular mealtimes may lead to a more balanced diet.  相似文献   
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