Amphipathic KALA fusogenic peptide enhances absorption of insulin and calcitonin by pulmonary membranes of rats.

OBJECTIVE: The aim was to investigate the absorption-enhancing effect (AEE) of lysine-alanine-leucine-alanine (KALA) repeating unit peptide upon pulmonary absorption of peptide and protein medicines among rats. MATERIALS AND METHODS: Absorption of insulin and calcitonin in the lung was evaluated using varying concentrations of KALA peptide from 0.1% to 1.0% (w/v). The study also examined the lung damage caused by the KALA peptide. RESULTS: KALA peptide with various concentrations improved the absorption of insulin and calcitonin in the lungs. It also reduced glucose and calcium levels in the blood compared to the control, with the AEE increasing in a concentration-dependent manner due to the KALA peptide. In toxicity assays, test results for protein and lactate dehydrogenase (LDH) in bronchoalveolar lavage fluid (BALF) did not show a significant increase in the presence of KALA peptide at various concentrations. This implies that the KALA peptide did not cause any membrane damage to lung tissues. In transmembrane electrical resistance (TEER) and permeability detection, a decrease in TEER value and an increase in papp value by the addition of KALA peptide indicated that KALA peptide had the ability to aid the drug delivery through epithelial cells via both paracellular and transcellular pathways. CONCLUSIONS: KALA peptides are suitable as an absorption enhancer at lower concentrations (below 1.0%, w/v) for improving the absorption of insulin and calcitonin from the lung with no observed toxic impact.

[Endoscopic features and clinical correlation analysis of 24 patients with Cronkhite-Canada syndrome].

Objective: To clarify the endoscopic changes prior to corticosteroid therapy in Cronkhite-Canada syndrome (CCS) patients and to explore the correlation between endoscopic features and clinical characteristics. Methods: A total of 24 CCS patients who were hospitalized in Peking Union Medical College Hospital from January 1999 to June 2019 and underwent gastroscopy and colonoscopy before corticosteroid therapy were retrospectively enrolled. The endoscopic images were re-interpreted. The demographic characteristics, clinical manifestations, laboratory tests and histopathological data were collected and analyzed. Results: Of all 24 patients, 15 (62.5%) were male and 9(37.5%) were female, with an average age of (59±10) years and disease course of 6 (1~36) months. Based on the endoscopic findings, the percentages of stomach, colon, duodenum, rectum and terminal ileum involvement were 100%, 100%, 95.7%, 66.7% and 50.0% respectively. Gastric involvement was more severe in the lower part of the body and the antrum of the stomach, while the cardia and the fundus were spared in 5 (20.8%) cases. Colonic involvement was more severe in the right colon. No patient showed remarkable esophageal involvement. The typical appearance under endoscopy were diffuse mucosal hyperemia and edema with polyps or nodular changes. The lesions may have mulberry-like or imbricate changes in severe cases. Lymphatic dilation in the duodenum was found in 47.8% patients. Most of the polyps were pedunculated or sub-pedunculated, with occasionally seen sessile polyps in the colon. The pit patterns of the 12 resected colon polyps in 11 patients could be classified as Kudo type Ⅲ(S), Ⅲ(L), Ⅳ and Ⅴ(I), among which 2 tubular adenomas had the Kudo type Ⅲ(L). Other resected polyps were hyperplastic polyps or CCS polyps. The disease duration prior to diagnosis was positively correlated with the maximum diameter of colon polyps (r=0.625, P=0.006). Serum albumin levels in patients with whole stomach involvement were significantly lower than those in patients with cardia spared [(29±8) g/L vs (37±5) g/L, P=0.034]. Conclusions: The typical initial endoscopic finding of CCS is multiple polyps or nodular changes on the background of diffuse hyperemia and edema lining the gastric, duodenal and colonic mucosa. Lymphatic dilatation in the duodenum could also be found. Some endoscopic features are correlated to clinical characteristics.

Characterization and modeling of the metal diffusion from deep ultraviolet photoresist and silicon-based substrate.

The radioactive tracer technique was applied to investigate the out-diffusion of the transition metals (Cu, Fe and Co) from deep ultraviolet (DUV) photoresist into underlying substrate. Two important process parameters, viz., baking temperatures and substrate types (i.e., bare silicon, polysilicon, silicon oxide and silicon nitride), were evaluated. Results indicate that the out-diffusion of Co is insignificant, irrespective of the substrate type and baking temperature. The out-diffusion of Cu is significant for substrates of bare silicon and polysilicon but not for silicon oxide and nitride; for Fe, the story is reversed. The substrate type appears to strongly affect the diffusion, while the baking temperature does not. Also, the effect of solvent evaporation was found to play an important role in impurity diffusion. Using the method of numerical analysis, a diffusion profile was depicted in this work to describe the out-diffusion of metallic impurities from photoresist layer under various baking conditions. In addition, the effectiveness of various wet-cleaning recipes in removing metallic impurities such as Cu, Fe and Co was also studied using the radioactive tracer technique. Among the six cleaning solutions studied, SC2 and SPM are the most effective in impurity removal. An out-diffusion cleaning model was first proposed to describe the cleaning process. A new cleaning coefficient, h(T), was suggested to explain the cleaning effect. The cleaning model could explain the tracer results.