Botulinum toxin blocks mast cells and prevents rosacea like inflammation

Background

Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.

Hypertension is a risk factor for adverse outcomes in patients with coronavirus disease 2019: a cohort study

Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.     

Implant wear induces inflammation, but not osteoclastic bone resorption, in RANK(-/-) mice.

Signaling of RANK (receptor activator of nuclear factor kappa B) through its ligand RANKL appears critical in osteolysis associated with aseptic loosening (AL). The purpose of this study was to investigate the role of RANK in a murine osteolysis model developed in RANK knockout (RANK(-/-)) mice. Ultra high molecular weight polyethylene (UHMWPE) debris was introduced into established air pouches on RANK(-/-) mice, followed by implantation of calvaria bone from syngeneic littermates. Wild type C57BL/6 (RANK(+/+)) mice injected with either UHMWPE or saline alone were included in this study. Pouch tissues were collected 14 days after UHMWPE inoculation for molecular and histology analysis. Results showed that UHMWPE stimulation induced strong pouch tissue inflammation in RANK(-/-) mice, as manifested by inflammatory cellular infiltration, pouch tissue proliferation, and increased gene expression of IL-1beta, TNFalpha, and RANKL. However, the UHMWPE-induced inflammation in RANK(-/-) mice was not associated with the osteoclastic bone resorption observed in RANK(+/+) mice. In RANK(+/+) mice subjected to UHMWPE stimulation, a large number of TRAP(+) cells were found on the implanted bone surface, where active osteoclastic bone resorption was observed. No TRAP(+) cells were found in UHMWPE-containing pouch tissues of RANK(-/-) mice. Consistent with the lack of osteoclastic activity shown by TRAP staining, no significant UHMWPE particle-induced bone resorption was found in RANK(-/-) mice. A well preserved bone collagen content (Van Gieson staining) and normal plateau surface contour [microcomputed tomography (microCT)] of implanted bone was observed in RANK(-/-) mice subjected to UHMWPE stimulation. In conclusion, this study provides the evidence that UHMWPE particles induce strong inflammatory responses, but not associated with osteoclastic bone resorption in RANK(-/-) mice. This indicates that RANK signaling is essential for UHMWPE particle-induced osteoclastic bone resorption, but does not participate in UHMWPE particle-induced inflammatory response.     

晶体玻璃体视网膜联合手术治疗复杂性视网膜脱离

目的探讨玻璃体视网膜手术（ｖｉｔｒｅｒｅｔｉｎａｌｓｕｒｇｅｒｙ，ＶＲ术）联合晶体切除／超声粉碎的效果。方法对８１例（８１只眼）应用晶体玻璃体视网膜联合手术（ｌｅｎｔｉｃｕｌａｒ－ｖｉｔｒｅｏｒｅｔｉｎａｌｓｕｒｇｅｒｙ，ＬＶＲ术）治疗的复杂性视网膜脱离进行回顾性分析。结果解剖性成功者６４只眼（７９．０１％），功能性成功者４５只眼（５５．５６％）；手术成功率显著降低的原因是前部增殖性玻璃体视网膜病变（ｐｒｏｌｉｆｅｒａｔｉｖｅｖｉｔｒｅｏ－ｒｅｔｉｎｏｐａｔｈｙ，ＰＶＲ）（成功率４２．８６％，Ｐ＜０．０１）和术中／术后眼内出血（成功率５８．８２％，Ｐ＜０．０２５）。结论ＬＶＲ术是治疗复杂性视网膜脱离的主要方法；显著影响手术预后的因素是前部ＰＶＲ和术中／术后眼内出血。     

医源性胆管狭窄X线表现

本文报道了１３例医源性胆管狭窄，分析其影像表现。特点为：环形狭窄；线样狭窄，包括规则的和不规则的线样狭窄；闭塞性狭窄；胆管闭塞和胆管中断分离。ＥＲＣＴ和ＰＣＴ对狭窄的形态，位置及长度显示优于ＣＴ和ＵＳ。     

Regulatory properties of brain glutamate decarboxylase (GAD): the apoenzyme of GAD is present principally as the smaller of two molecular forms of GAD in brain

The apoenzyme of glutamate decarboxylase [enzyme without bound cofactor, pyridoxal 5'-phosphate (pyridoxal-P)] serves as a reservoir of inactive glutamate decarboxylase (GAD) that can be activated when additional GABA synthesis is required. We have investigated which of two molecular forms of GAD is present as apoenzyme in synaptosomes and in cortex, caudate nucleus, hippocampus, and cerebellum of rat brain. Endogenous glutamate apodecarboxylase (apoGAD) was labeled by incubating extracts of synaptosomes or punches of each region with 32P-pyridoxal-P, followed by reduction with NaBH4, to link covalently the 32P-pyridoxal-P to GAD. Proteins were separated by SDS-PAGE. Punches from all four brain regions and forebrain synaptosomes contained two forms of GAD with apparent Mrs of 63 and 65 kDa as identified by immunoblotting with four antiGAD sera. Punches and synaptosomes contained a major 32P-pyridoxal-P-labeled band with an apparent Mr of 63 kDa that was stained on immunoblots by the antiGAD serum 1440 and the monoclonal antibody GAD-6, and a minor labeled band at 65 kDa that was stained by the 1440, 6799, and K2 antisera. Synaptosomes contained remarkably few other strongly labeled proteins, but punches contained several other labeled bands. Three additional lines of evidence indicate that the labeled 63-kDa protein is apoGAD: (1) it was purified by immunoaffinity chromatography with the GAD-1 monoclonal antibody; (2) it yielded one major labeled peptide when digested with chymotrypsin, and that peptide appeared identical in peptide-mapping experiments to the labeled active-site peptide isolated from chromatographically prepared rat brain GAD; and (3) its labeling was selectively blocked by 4-deoxypyridoxine 5'-phosphate, a competitive inhibitor of the binding of pyridoxal-P to GAD.(ABSTRACT TRUNCATED AT 250 WORDS)     

Efficacy of radiology of the esophagus for evaluation of dysphagia

The efficacy of radiology in evaluating dysphagia was studied in 86 patients by comparison to endoscopic findings. In the 66 patients with endoscopic abnormalities radiology was correct in 54, for a sensitivity of 82%. Sensitivity of radiology improved to 95% if mild esophagitis was excluded. In the 20 patients with normal endoscopy, radiology was normal in 18 (90%). Thus radiology proved to be a reliable means of evaluating the esophagus in patients with dysphagia.