Which plantar region can predict peripheral arterial disease by using laser speckleflowgraphy?

Laser speckle flowgraphy (LSFG) is a new device that can measure skin blood flow and capture the movement of erythrocytes. However, there are a few reports on the use of LSFG to estimate skin blood flow, especially in the lower extremities. We aimed to compare plantar skin blood flow between patients with and without peripheral arterial disease (PAD) to discern the extent to which LSFG could accurately predict PAD. We prospectively measured the plantar skin blood flow in 28 patients with PAD and 37 participants without PAD at two hospitals from 2017 to 2021, using the ankle-brachial index (ABI) and LSFG. We partitioned the plantar into 12 parts: digits 1-5, medial metatarsal, middle metatarsal, lateral metatarsal, medial arch, middle arch, lateral arch, and heel, and compared the difference between the two groups and the area under the curve (AUC) of each point. Statistical analyses were performed to determine the sensitivity, specificity, false-positive rate, and false-negative rate at high accuracy points of AUC and ABI. There was a significant difference among the 12 points between the two groups, and the ratio using toe 1 and toe 5 was highly accurate. The ratio using toe 1 indicated higher sensitivity (89 vs. 82%), higher false-positive rate (22 vs. 4%), lower specificity (81 vs. 97%), and an equivalent false-negative rate (9 vs. 12%) to that of the ABI. These findings could facilitate the use of LSFG to estimate the skin blood flow condition in the plantar skin. Our results indicate that measuring toe 1 using LSFG could be used to somewhat assess PAD.

Distribution of thymidine phosphorylase activity in gastric carcinoma and adjacent normal gastric tissue.

BACKGROUND/AIMS: Thymidine phosphorylase was reported to be identical to the angiogenic factor, platelet-derived endothelial cell growth factor. In this study we investigated the distribution of thymidine phosphorylase activity in human gastric carcinoma or normal gastric tissue using the ELISA system. METHODOLOGY: A longitudinal slice in the center of the gastric carcinoma of resected specimens from 6 patients with gastric carcinoma was used, and thymidine phosphorylase activity was mapped in each case. RESULTS: In all cases, the thymidine phosphorylase activities were significantly higher in tumors than adjacent normal gastric tissues. The amount and distribution of thymidine phosphorylase activity were different between intestinal-type and diffuse-type carcinoma. The thymidine phosphorylase activities in the invasive front of tumor were significantly lower than those in the other part in intestinal-type carcinoma. CONCLUSIONS: The ELISA system used in this study proved useful for the determination of thymidine phosphorylase activities in tissue sections.