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501.
502.
Transmissible spongiform encephalopathies (TSE) is a group of diseases that is unique in comprising disorders that can occur sporadically, are hereditary and/or infectious. The transmissible pathogen--the prion--is distinct from all other pathogens in being devoid of nucleic acids. During the elucidation of these disorders, many different--and contradictory--theories have been put forward. Early researchers, mostly driven by the economic impact of these diseases on sheep farming, engaged in heavy disputes concerning heredity vs. infectivity of scrapie. Following the experimental demonstration of scrapie's infectivity during the 20th century, research focused on the characterization of the nature of the transmissible agent. The current work comprehensively summarizes the available early literature on TSE research. A review of the historical literature is presented, describing the efforts in breeding, transmission experiments, and theories about the nature of the infectious agent.  相似文献   
503.
504.
Glioblastoma is the most common primary malignant brain tumor in adults with an overall survival of only 14.6 months. Hypoxia is known to play a role in tumor aggressiveness but the influence of hypoxia on the immune microenvironment is not fully understood. The aim of this study was to investigate the expression of immune-related proteins in normoxic and hypoxic tumor areas by digital spatial profiling. Tissue samples from 10 glioblastomas were stained with a panel of 40 antibodies conjugated to photo-cleavable oligonucleotides. The free oligo-tags from normoxic and hypoxic areas were hybridized to barcodes for digital counting. Differential expression patterns were validated by Ivy Glioblastoma Atlas Project (GAP) data and an independent patient cohort. We found that CD44, Beta-catenin and B7-H3 were upregulated in hypoxia, whereas VISTA, CD56, KI-67, CD68 and CD11c were downregulated. PD-L1 and PD-1 were not affected by hypoxia. Focusing on the checkpoint-related markers CD44, B7-H3 and VISTA, our findings for CD44 and VISTA could be confirmed with Ivy GAP RNA sequencing data. Immunohistochemical staining and digital quantification of CD44, B7-H3 and VISTA in an independent cohort confirmed our findings for all three markers. Additional stainings revealed fewer T cells and high but equal amounts of tumor-associated microglia and macrophages in both hypoxic and normoxic regions. In conclusion, we found that CD44 and B7-H3 were upregulated in areas with hypoxia whereas VISTA was downregulated together with the presence of fewer T cells. This heterogeneous expression should be taken into consideration when developing novel therapeutic strategies.  相似文献   
505.

Objective

To report on our first-in-human experience using the LithoVue Elite™ ureteroscope (Boston Scientific Corp., Marlborough, MA, USA) to measure intrarenal pressure (IRP) during flexible ureteroscopy.

Patients and Methods

A single-arm retrospective observational analysis was performed in 50 consecutive patients undergoing ureteroscopic lithotripsy using the LithoVue Elite™ system with pressure sensing capability between April 2022 and February 2023 at two centres. A pressure bag set at 150 mmHg or hand irrigation with a 60-mL syringe was used for irrigation and a ureteric access sheath (UAS) was placed at the physician's discretion. Median and maximum IRPs, and relative cumulative time exceeding 20, 40, 60, 80, 100, 120, 140, 160, and 200 mmHg per total procedure time were analysed. The two-sample Mann–Whitney U-test was used, with statistical significance set at P < 0.05.

Results

The median (interquartile range [IQR]) patient age and body mass index (BMI) was 62.5 (46.7–68.2) years and 27.6 (23.3–32.1) kg/m2, respectively. During the median (IQR) total procedure time of 31.9 (17.4–44.9) min, the median and maximum IRPs were 28.5 (20.0–47.5) and 174.0 (133.5–266.0) mmHg, respectively. IRP remained at <60 mmHg during 92% of the procedure times. Patients with Asian ethnicity, and those without pre-stenting or UAS use exhibited longer cumulative/total durations exceeding pre-defined IRP cut-off values. The smaller 10/12-F UAS did not lower pressures as much as the 11/13-F or 12/14-F UAS (P < 0.001). Age, diabetes, hypertension, preoperative α-blockade, stone size, and BMI did not show any statistically significant associations with IRP.

Conclusions

The IRP can now be routinely measured during ureteroscopy. Patients had a median IRP of 28.5 mmHg and a maximum of 174 mmHg. Using a smaller UAS (10/12 F), Asian ethnicity, and tight ureters were found to have higher IRPs.  相似文献   
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