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Eye drops are envisaged as the most promising non-invasive formulation for the treatment of the ocular posterior segment diseases, while it is hindered by a series of complex ocular barriers, both static and dynamic in nature. In this context, we propose a single molecule nanomedicine based on host-guest chemistry to achieve highly efficient drug delivery targeted to ocular posterior segment. Sulfonated azocalix[4]arene (SAC4A) serves as the single molecule carrier, owing the multiple features of small size (24.0 Å in length, 21.2 Å in width, 14.8 Å in height with a Van der Waals volume of 930 Å 3 ), negative charge, hydrophilicity, loading universality and hypoxia-triggered release. As a proof-of-concept, an eye drop formed by the complexation of SAC4A with sunitinib (SUN) is prepared to treat wet age-related macular degeneration (wAMD). SAC4A successfully transports SUN to the ocular posterior segment (the amount of SUN reaching the retinal-choroid tissue in the SUN@SAC4A group was 2.47 times larger than that in the SUN group at 30 min), significantly enhancing its anti-choroidal neoangiogenesis effect of SUN to wAMD, which played a key role in the treatment. We believe that the single molecule nanomedicine paradigm is highly amenable for treating various ocular posterior segment diseases in the future., (Copyright © 2024. Published by Elsevier B.V.)

According to the 6th Second Class Forest Resource Inventory data in Linzhi area of Tibet, and by using the volume source biomass method and average-biomass computing method, in combining with the molecular formula carbon rate of different tree species, this paper estimated the carbon storage and carbon density of different standing forests and their components in the area, and analyzed the spatial distribution patterns of the carbon storage and carbon density. In 2004, the forest carbon storage in the area was 2. 43x10(8) t, and the average forest carbon density was 76.01 t.hm-2. The carbon storage followed the sequence of standing forest > shrub forest > open forest > scattered trees > bamboo forest > four-side trees. Standing forests had a carbon storage 2.51x10(5)-1.27x10(8) t, accounting for 92.0% of the total forest carbon storage in the area. The average carbon density of various standing forests was 103.16 t.hm-2, and fir forest had the highest carbon storage and carbon density. From the view of regional distribution, the forest carbon storage presented a trend of increased from northwest to southeast, whereas the forest carbon density tended to be increased from southwest to northeast. The carbon storage of the standing forests was mainly consisted by mature and over-matured forests, and the carbon density of over-matured forests was the highest among all the age classes' forests. The forest carbon storage in Linzhi area would be increased with the increase of over-matured forests, but tended to be decreased with the death and decomposition of over-matured forests.

Objective: To study the distribution of genomovars and microevolution of Yersinia pestis in the Qinghai-Tibet Plateau., Methods: Primer pairs targeting the twenty-two different regions(DFRs) were designed for detecting the presence or deletion of each DFR in 297 strains isolated from the Qinghai-Tibet Plateau., Results: 9 genomovars, i. e. Genomovar 1, 5, 6, 7, 8, 10, 11, new type and Ype-ancestor were identified in the Marmota himalayana plague focus of the Qinghai-Tibet Plateau. Among these genomovars, genomovar 5,8 and 10 were dominant types. The total rate of the three genomovars was 80.6% (204/253) and the genomovars in different regions were different. All of 44 strains of Y. pestis in the Microtus fuscus plague focus of the Qinghai-Tibet Plateau belonged to genomovar 14., Conclusion: The distribution of genomovars of Y. pestis in the Qinghai-Tibet plateau had remarkable characteristics geographically. Based on the distribution of genomovars of Y. pestis, the routes of transmission and microevolution of Y. pestis were proposed.