Development of 2D and 3D Mucus Models and Their Interactions with Mucus-Penetrating Paclitaxel-Loaded Lipid Nanocapsules

Purpose

To study, diffusion through mucus (3D model) of different formulations of paclitaxel loaded lipid nanocapsules (Ptx-LNCs), to interpret the results in the light of LNC behavior at air-mucus interface (2D model).

Methods

LNC surface properties were modified with chitosan or poly(ethylene glycol) (PEG) coatings of different size (PEG 2,000 to 5,000 Da) and surface charges. LNC diffusion through 446 μm pig intestinal mucus layer was studied using Transwell^®. LNCs were spread at the air-water-mucus interface then interfacial pressure and area changes were monitored and the efficiency of triglyceride (TG) inclusion was determined.

Results

Ptx-LNCs of surface charges ranging from ?35.7 to +25.3 mV were obtained with sizes between 56.2 and 75.1 nm. The diffusion of paclitaxel in mucus was improved after encapsulation in neutral or positively charged particles (p?<?0.05 vs Taxol^®). No significative difference was observed in the 2,000–5,000 PEG length for diffusion both on the 2D or 3D models. On 2D model positive or neutral LNCs interacted less with mucus. Highest efficiency of TG inclusion was observed for particles with smallest PEG length.

Conclusions

The results obtained with 2D and 3D model allowed us to select the best candidates for in vivo studies (neutral or positive LNCs with smaller PEG length).     

Evaluation of current molecular approaches for genotyping of Campylobacter jejuni strains

Campylobacter jejuni has been recognized as the most common bacterial cause of gastroenteritis worldwide, in both developed and developing countries, since the late 1970s. A number of genotyping schemes have been developed to identify the sources and route of transmission of these foodborne pathogens so that proper control measures can be developed. In this review, we provide current genotypic schemes developed for Campylobacter spp. (particularly C. jejuni) over the last decades, along with an evaluation of the strength and weakness of these techniques and their applications.     

Accounting for data variability,a key factor in in vivo/in vitro relationships: application to the skin sensitization potency (in vivo LLNA versus in vitro DPRA) example

When searching for alternative methods to animal testing, confidently rescaling an in vitro result to the corresponding in vivo classification is still a challenging problem. Although one of the most important factors affecting good correlation is sample characteristics, they are very rarely integrated into correlation studies. Usually, in these studies, it is implicitly assumed that both compared values are error‐free numbers, which they are not. In this work, we propose a general methodology to analyze and integrate data variability and thus confidence estimation when rescaling from one test to another. The methodology is demonstrated through the case study of rescaling the in vitro Direct Peptide Reactivity Assay (DPRA) reactivity to the in vivo Local Lymph Node Assay (LLNA) skin sensitization potency classifications. In a first step, a comprehensive statistical analysis evaluating the reliability and variability of LLNA and DPRA as such was done. These results allowed us to link the concept of gray zones and confidence probability, which in turn represents a new perspective for a more precise knowledge of the classification of chemicals within their in vivo OR in vitro test. Next, the novelty and practical value of our methodology introducing variability into the threshold optimization between the in vitro AND in vivo test resides in the fact that it attributes a confidence probability to the predicted classification. The methodology, classification and screening approach presented in this study are not restricted to skin sensitization only. They could be helpful also for fate, toxicity and health hazard assessment where plenty of in vitro and in chemico assays and/or QSARs models are available. Copyright © 2016 John Wiley & Sons, Ltd.     

Dynamic control of protein diffusion within the granal thylakoid lumen

The machinery that conducts the light-driven reactions of oxygenic photosynthesis is hosted within specialized paired membranes called thylakoids. In higher plants, the thylakoids are segregated into two morphological and functional domains called grana and stroma lamellae. A large fraction of the luminal volume of the granal thylakoids is occupied by the oxygen-evolving complex of photosystem II. Electron microscopy data we obtained on dark- and light-adapted Arabidopsis thylakoids indicate that the granal thylakoid lumen significantly expands in the light. Models generated for the organization of the oxygen-evolving complex within the granal lumen predict that the light-induced expansion greatly alleviates restrictions imposed on protein diffusion in this compartment in the dark. Experiments monitoring the redox kinetics of the luminal electron carrier plastocyanin support this prediction. The impact of the increase in protein mobility within the granal luminal compartment in the light on photosynthetic electron transport rates and processes associated with the repair of photodamaged photosystem II complexes is discussed.     

The experience of modern methods of enteroscopy in the diagnosis of Crohn's disease

The aim of the study is to evaluate the possibilities of videocapsule endoscopy (VCE), single and double balloon enteroscopy in diagnosis of small bowel Crohn's disease. MATERIAL AND METHODS: From V.2003 to IV.2011 we observed 52 pts. with suspected small bowel Crohn's disease; 8 (15.4%) of them were operated urgently because of complications. Another 44 pts (m-23, f-21, ranged from 15-72 years, mean age 37.5 +/- 12.0 years) underwent complex examination including 19 VCE and 49 BAE in 32 pts.(incl. 7 after VCE). RESULTS: Typical Crohn's disease appearance was found in 15 (34.1%) pts (incl. 4pts after VCE) from 44 who were examined endoscopically. In 8 pts we've revealed stenosis, in 4 of them we've passed through the ileocecal valve stenosis by bouginage with the enteroscope and were able to examine superior area. After performing target biopsy from the small bowel mucosal lesions Pirogov - Langhans cells were found in 5 (33.3%) pts. We haven't found any signs of Crohn's disease in 17 pts. (no abnormalities found-6, enteritis-9, celiac disease-1, NSAID-ulcers-1). Conservative treatment has been applied in 10 (66.7%) pts., surgical intervention - in 5 (33.3%) pts. There was a capsule retention in 2 (10.5%) pts. There were no any complications in BAE. CONCLUSION; The use of the new enteroscopic techniques substantially improves the diagnosis of small bowel     

Hospitalizations due to spontaneous intracerebral hemorrhage in the region of Nis (Serbia): 11-year time-series analysis

Background

The study of seasonal variability of intracerebral hemorrhage (ICH) occurrence may contribute to a better understanding of the nature of this disease and open up new perspectives in its prevention. The aim of this study was to test seasonal patterns in the number of admissions of ICH patients and determine which months have maximal and minimal number of admissions.

Methods

The main data source for this study was a hospital-based registry at the Clinic of Neurology in Nis, Serbia. During the studied period (1997-2007) a total of 1569 ICH patients were registered. Time series, consisting of the monthly number of hospitalized patients, for the 128 months of the study duration, has been successfully modeled using the multiplicative Auto Regressive Integrated Moving Average (ARIMA) model.

Results

Using the maximum likelihood method, utilizing Melrad's algorithm, the parameters of this ARIMA model have been calculated: constant (estimate 12.068, p < 0.001), auto regressive-AR(1) (estimate 0.866, p < 0.001), moving average-MA(1) (estimate 0.775, p < 0.001), seasonal moving average-SMA(12) (estimate −0.198, p = 0.036). ARIMA modeling has been successful and showed that there is a clear seasonal pattern in the data analyzed.

Conclusion

Based on the seasonal multiplicative ARIMA model and the seasonal time series decomposition, we showed that, in the period covered by the study, the peak of admissions occurred in March, and the trough of admissions was found in August.     

Changes in health-related quality of life with long-term eltrombopag treatment in adults with persistent/chronic immune thrombocytopenia: Findings from the EXTEND study

Patients with persistent/chronic immune thrombocytopenia (cITP) have low platelet counts, increased risk of bleeding and bruising, and often suffer from reduced health-related quality of life (HRQoL). cITP treatments may either improve HRQoL by increasing platelet counts or decrease it because of side effects. The open-label EXTEND study (June 2006 to July 2015) evaluated long-term safety, tolerability, and efficacy of eltrombopag (an oral thrombopoietin-receptor-agonist) in adults with cITP who completed a previous eltrombopag ITP trial. The final results of EXTEND were published and used to assess changes in patient-reported HRQoL over time and association between HRQoL and platelet response. Four validated HRQoL instruments were administered: SF-36v2 including physical component summary (PCS) and Mental Component Summary; Motivation and Energy Inventory Short Form (MEI-SF); Fatigue Subscale of FACIT (FACIT-Fatigue); and FACT-Thrombocytopenia Subscale Six-Item Extract (FACT-Th6). For the 302 patients enrolled, median duration of eltrombopag treatment was 2.37 years. All 4 HRQoL instruments demonstrated positive mean changes from baseline over time adjusted for patient baseline characteristics and rescue therapy use, and had positive association with platelet response (platelet count ≥30 × 10⁹/L; ≥50 × 10⁹/L; and ≥50 × 10⁹/L and >2 times baseline). Improvements from baseline started within 3 months and persisted through 5 years of treatment for FACIT-Fatigue and FACT-Th6 (P <.05 for nearly all time points); through 2.5 years for SF-36v2 PCS and less consistently for the MEI-SF. In conclusion, in addition to eltrombopag increasing platelet counts and reducing bleeding/bruising, it also alleviated fatigue, concerns about bleeding and bruising, and improved physical function in many patients, especially responders.