Validating the accuracy of the Hendrich II Fall Risk Model for hospitalized patients using the ROC curve analysis.

This retrospective study was conducted at a medical center in southern Taiwan to assess the accuracy of the Hendrich II Fall Risk Model (HIIFRM) in predicting falls. Sensitivity, specificity, accuracy, and optimal cutoff points were analyzed using receiver operating characteristic (ROC) curves. Data analysis was conducted using information from the electronic medical record and patient safety reporting systems, capturing 303 fall events and 47,146 non-fall events. Results revealed that at the standard threshold of HIIFRM score ≥5, the median score in the fall group was significantly higher than in the non-fall group. The top three units with HIIFRM scores exceeding 5 were the internal medicine (50.6%), surgical (26.5%), and oncology wards (14.1%), indicating a higher risk of falls in these areas. ROC analysis showed an HIIFRM sensitivity of 29.5% and specificity of 86.3%. The area under the curve (AUC) was 0.57, indicating limited discriminative ability in predicting falls. At a lower cutoff score (≥2), the AUC was 0.75 (95% confidence interval: 0.666-0.706; p < 0.0001), suggesting acceptable discriminative ability in predicting falls, with an additional identification of 101 fall events. This study emphasizes the importance of selecting an appropriate cutoff score when using the HIIFRM as a fall risk assessment tool. The findings have implications for fall prevention strategies and patient care in clinical settings, potentially leading to improved outcomes and patient safety.

The observation records from whale and dolphin watching inshore of Hualien, eastern Taiwan.

Background: The eastern waters of Taiwan have been lacking baseline and research data for several years. This study was initiated by Kuroshio Ocean Education Foundation (KOEF) in collaboration with the Turumoan whale-watching company since 1998, collecting long-term ecological data for cetaceans in the inshore of Hualien, eastern Taiwan. This dataset includes 10,675 records of cetacean sightings from June 1998 to December 2021. Collection of cetacean sighting records was paused for one year in 2001 due to budgetary reasons. All of the sighting records were collected by whale-watching boat guides that were trained by KOEF. Following a standardised protocol, guides used a handheld GPS device and cetacean sighting record sheets to document information about the cetacean species identification, location, time, number of individuals, the presence of mother-calf pairs and mixed-species groups and other states of each sighting during a whale-watching tour. The collection of citizen-science data during this period has significantly advanced Taiwan's cetacean baseline data in the study area. Additionally, we make data available to the public in the form of citizen-science, making a substantial contribution to the advancement of ocean scientific research. We have published the dataset on Global Biodiversity Information Facility, allowing users around the world to download the dataset. New information: This is currently the largest dataset of cetacean sighting records in Taiwan (last updated on 2023-09-05). We have also recorded several species on the International Union for Conservation of Nature (IUCN) Red List categorised as "Data Deficient" during our survey inshore of Hualien, eastern Taiwan, including Ginkgo-toothed beaked whales (Mesoplodonginkgodens Nishiwaki & Kamiya, 1958), Omura's whales (Balaenopteraomurai Wada, Oishi & Yamada, 2003) and killer whales (Orcinusorca (Linnaeus, 1758)). There are also sperm whales (Physetermacrocephalus Linnaeus, 1758), categorised as "Vulnerable" in the IUCN Red List and false killer whales (Pseudorcacrassidens (Owen, 1846)), categorised as "Near Threatened". This study is also the first and only long-term study that has documented cetaceans in the study area.

Compare the effectiveness of extracorporeal shockwave and hyperbaric oxygen therapy on enhancing wound healing in a streptozotocin-induced diabetic rodent model.

Studies have revealed that both extracorporeal shock-wave therapy (ESWT) and hyperbaric oxygen therapy (HBOT) can accelerate wound healing. This study aimed to compare the effectiveness of ESWT and HBOT in enhancing diabetic wound healing. A dorsal skin defect in a streptozotocin-induced diabetes rodent model was used. Postoperative wound healing was assessed once every 3 days. Histologic examination was performed with hematoxylin and eosin staining. Proliferation marker protein Ki-67 (Ki-67), endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF), and 8-hydroxy-2-deoxyguanosine (8-OHdG) were evaluated with immunohistochemical (IHC) staining. The wound area was significantly reduced in the ESWT and HBOT groups compared to that in the diabetic controls. However, the wound healing time was significantly increased in the HBOT group compared to the ESWT group. Histological findings showed a statistical increase in neovascularization and suppression of the inflammatory response by both HBOT and ESWT compared to the controls. IHC staining revealed a significant increase in Ki-67, VEGF, and eNOS but suppressed 8-OHdG expression in the ESWT group compared to the HBOT group. ESWT facilitated diabetic wound healing more effectively than HBOT by suppressing the inflammatory response and enhancing cellular proliferation and neovascularization and tissue regeneration.

Compound cellular stress maximizes apoptosis independently of p53 in glioblastoma.

We examined the apoptotic response of two glioblastoma cells, p53 wild type U87 and p53 mutated T98G, to doxorubicin, bortezomib, and vorinostat, which respectively target DNA, 26S proteasome and histone deacetylase, to clarify p53's function in apoptosis. We demonstrated that doxorubicin induced apoptosis in U87 cells but not in T98G cells. The level of p53 was definitively correlated to the extent of DNA damage and apoptosis initiation. Dominant-negative p53 reduced p21 expression, but did not affect doxorubicin-induced apoptosis, so the transcriptional activity of p53 seemed not to participate in doxorubicin-induced apoptosis. However, p53 concentrated into the nucleus during heavy apoptosis. Bortezomib could induce apoptosis in U87 with high sensitivity and T98G cells with low sensitivity. In contrast, vorinostat promoted apoptosis in both U87 and T98G cells and reduced the basal level of p53 in U87 cells, indicating that p53 played no role in the vorinostat-induced apoptosis. To clearly define the role of p53 in bortezomib- and doxorubicin-induced apoptosis, we combined doxorubicin with bortezomib to treat U87 cells to assess this combination's effect on apoptosis and p53 status. Interestingly, the combination of doxorubicin with bortezomib engendered compound stress, resulting in a synergistic outcome for apoptosis in U87 cells. However, the amounts of p53 in the total count and in the nucleus were much lower with the combination than with doxorubicin alone, suggesting that p53 played no role in either the compound stress, doxorubicin-only or bortezomib-induced apoptosis.

County-Wide Mortality Assessments Attributable to PM2.5 Emissions from Coal Consumption in Taiwan.

Over one-third of energy is generated from coal consumption in Taiwan. In order to estimate the health impact assessment attributable to PM2.5 concentrations emitted from coal consumption in Taiwan. We applied a Gaussian trajectory transfer-coefficient model to obtain county-wide PM2.5 exposures from coal consumption, which includes coal-fired power plants and combined heat and power plants. Next, we calculated the mortality burden attributable to PM2.5 emitted by coal consumption using the comparative risk assessment framework developed by the Global Burden of Disease study. Based on county-level data, the average PM2.5 emissions from coal-fired plants in Taiwan was estimated at 2.03 ± 1.29 (range: 0.32-5.64) µg/m3. With PM2.5 increments greater than 0.1 µg/m3, there were as many as 16 counties and 66 air quality monitoring stations affected by coal-fired plants and 6 counties and 18 monitoring stations affected by combined heat and power plants. The maximum distances affected by coal-fired and combined heat and power plants were 272 km and 157 km, respectively. Our findings show that more counties were affected by coal-fired plants than by combined heat and power plants with significant increments of PM2.5 emissions. We estimated that 359.6 (95% CI: 334.8-384.9) annual adult deaths and 124.4 (95% CI: 116.4-132.3) annual premature deaths were attributable to PM2.5 emitted by coal-fired plants in Taiwan. Even in six counties without power plants, there were 75.8 (95% CI: 60.1-91.5) deaths and 25.8 (95%CI: 20.7-30.9) premature deaths annually attributable to PM2.5 emitted from neighboring coal-fired plants. This study presents a precise and effective integrated approach for assessing air pollution and the health impacts of coal-fired and combined heat and power plants.

Quantity and type of coastal debris pollution in Taiwan: A rapid assessment with trained citizen scientists using a visual estimation method.

Ongoing monitoring of the distribution and composition of coastal debris is a prerequisite for efficient management and cleanups. Therefore, we conducted a rapid assessment of coastal debris along the 1210 km coastline of Taiwan using a visual estimation method. Forty-nine citizen scientists were intensively trained to correctly identify the volume and types of debris. At 121 sampling locations randomly placed along Taiwan's coastline, the citizen scientists recorded the pollution level and the three most abundant debris types within a 100-m transect during four surveys in 2018-2019. Averaging over the four surveys, the mean amount of coastal debris was estimated to be 406.6 kg/km, and the three most abundant debris types were plastic bottles, foamed plastics, and fishing nets and ropes. Using a statistical test which avoids spatial pseudoreplication, we showed that north-facing coastlines had significantly higher pollution levels than the other coastlines, which we suggest is deposited there during strong winter winds. We also showed that fishery-related debris was a much more important part of coastal debris when the volume of it was determined instead of just the number of items. Mean pollution levels were further associated with wind speed, coastline type, and the distance to presumed pollution sources. Our results compare well with similar surveys conducted in Japan and South Korea. In each country, the debris was highly aggregated, which means it was concentrated in a few highly polluted localities. Therefore, the visual estimation method can effectively guide cleanup efforts to the most polluted areas and also reliably generate long-term monitoring data.

Adaptation to an Unfamiliar Accent by Child L2 Listeners.

The study examines school-aged L2 listeners' adaptation to an unfamiliar L2 accent and learner variables predicting such adaptation. Fourth-grade Mandarin L1 learners of English as a foreign language (N = 117) listened to a story twice in one of three accent conditions. In the single-talker condition, the story was produced by an Indian English (IE) speaker. In the multi-talker condition, the story was produced by two IE speakers. In the control condition, the story was produced by a Mandarin-accented speaker. Children's (re)interpretation of IE words/nonwords was assessed by referent selection tests administered before and after the first and the second exposures to the story. Repeated exposure to IE-accented speech forms influenced performance: the participants demonstrated better recognition of IE words across the referent selection tests but worse (re)interpretation of IE nonwords sounding similar to existing lexical items. Exposure to an IE-accented story yielded an additional advantage in word recognition, but the advantage was limited to words heard in the story. Furthermore, children's English phonological awareness, phonological memory, and vocabulary predicted their reinterpretation performance of the accented forms. These results suggest that school-aged L2 listeners with better phono-lexical representations develop better capacity in adapting to an unfamiliar accent of a foreign language by loosening their acceptability criteria for word recognition but the adaptation does not necessarily entail perceptual tuning to the specific phonological categories of the accent.

Transcription-independent and -dependent p53-mediated apoptosis in response to genotoxic and non-genotoxic stress.

We previously reported that p53-mediated apoptosis is determined by severity of DNA damage, not by the level of p53, in doxorubicin-treated prostate cancer cells. In addition to doxorubicin, our results here indicated that camptothecin and bortezomib, which are a topoisomerase 1 poison and a 26 S proteasome inhibitor, respectively, could also induce apoptosis in a p53-dependent manner in prostate cancer. Then, we examined whether p53-mediated apoptosis induced by genotoxic and non-genotoxic stress occur in the same or a different way. By using dominant negative p53 to compete with wild-type p53 in transcription activity, we demonstrated that p53-mediated apoptosis in response to doxorubicin- or camptothecin-induced genotoxic stress is transcription-independent. In contrast, p53-mediated apoptosis from bortezomib-induced stress is transcription-dependent. Interestingly, we also found that doxorubicin-induced p21 expression is activated by p53 in transcription-dependent manner, while camptothecin-induced p21 expression is p53-independent. We then investigated the p53 ratio of nucleus to cytosol corresponding to low and high dose doxorubicin, camptothecin, or bortezomib treatment. The results suggested that p53 translocation from cytoplasm to nucleus actively drives cells toward apoptosis in either transcription-dependent or -independent manner for responding to non-genotoxic or genotoxic stress, respectively.

Health impact assessment of PM2.5 from a planned coal-fired power plant in Taiwan.

PURPOSE: To investigate the impact of a planned coal-fired power plant (CFPPT) in Shenao on air quality and health at subnational levels in Taiwan. METHODS: We applied the Gaussian trajectory transfer-coefficient (GTx) model to estimate annual average PM2.5 (particulate matter with aerodynamic diameter less than 2.5 µm) increments in 19 Taiwanese cities and counties caused by CFPPT operation. A population health risk assessment was performed by incorporating evidence of the health effects of PM2.5 provided by prospective studies and estimating long-term PM2.5 exposure. Additionally, we considered ischemic heart disease, stroke, lung cancer, and chronic obstruct pulmonary disease as the primary outcomes. The population-attributable fraction was used to estimate the county-level mortality burden attributable to CFPPT-generated PM2.5 in 2025. RESULTS: The estimated annual PM2.5 increments ranged from 0.004 µg/m3 (Taitung County) to 0.28 µg/m3 (Hsinchu County) due to the Shenao CFPPT. The total and premature deaths attributable to PM2.5 from Shenao CFPPT operation in Taiwan during 2025-2040 would be 576 (95% confidence interval [CI]: 537-619) and 145 (95% CI: 136-155), respectively. Notably, we estimated 198 (95% CI: 169-234) deaths and 58 (95% CI: 51-66) premature deaths, respectively, in New Taipei City, which accounted for over a quarter of the total deaths. Overall, the mortality rate attributable to the Shenao CFPPT in Taiwan was 6 per 10,000. CONCLUSION: A scientific approach should be adopted for assessing the impacts of CFPPT operation on population health, which can serve as a valuable policymaking reference for the government.

Type and quantity of coastal debris pollution in Taiwan: A 12-year nationwide assessment using citizen science data.

Man-made coastal debris pollution is a growing concern for Taiwan. In 2004, Taiwanese environmental organizations led by the "Society of Wilderness" began gathering data on 19 categories of debris items collected during cleanup events. We present our analysis of the resulting 12-year dataset collated from 541 events held between October 2004 and December 2016. In total, 904,302 items weighing 131,358.3 kg were collected, and 63.6% and 27.2% of items were made of either plastic or plastic mixed with other materials, respectively. The five most commonly recorded debris categories were plastic shopping bags, plastic bottle caps, disposable tablewares, fishing equipment, and plastic drinking straws. We estimated that during the 12-year period on average between 3.7 and 7.9 million items weighing 560-1110 metric tons polluted Taiwan's coastline. We offer recommendations for improving the quality of data collected during Taiwan's cleanup events and report some policy changes due partly to previous reports of this dataset.

Evaluating the effectiveness of a novel atomized liquid needle-free transdermal delivery system.

Needle-free jet injections constitute a crucial method for drug delivery. A novel liquid drug delivery system has been proposed recently, in which pressure atomizes liquid before delivering that atomized liquid to the patient's body; however, the mechanism and efficiency of the system are unclear. This study explored the shot delivery pressure, penetration depth, and cumulative amount of permeation of this system. This system was used to deliver 0.5% (w/v) methylene blue to agarose phantoms at various shot delivery pressures. Shots of methylene blue were also delivered to porcine skin samples at different shot delivery frequencies for light microscopy evaluation. A commercial microneedle array was used for comparing the effectiveness of the skin penetration depths. The array was gently stamped against porcine skin; methylene blue was subsequently applied to the area for different time points, followed by microscopic observations. In vitro skin penetration was tested using static Franz diffusion cells over 8 h. Finally, the feasibility of the system's clinical application was evaluated by analyzing the local analgesic effect in a heat nociceptive animal model. The penetration depths created using 100 shots at 100 psi were similar to those created using the commercial microneedle array for 2 h. Thermal stimulation responses showed that 15 min after diclofenac sodium was delivered by the system, heat nociception was significantly attenuated for 60 min. Our study presents a novel delivery system that may be useful for future clinical applications.

Extracting phonological patterns for L2 word learning: the effect of poor phonological awareness.

An implicit word learning paradigm was designed to test the hypothesis that children who came to the task of L2 vocabulary acquisition with poorer L1 phonological awareness (PA) are less capable of extracting phonological patterns from L2 and thus have difficulties capitalizing on this knowledge to support L2 vocabulary learning. A group of Chinese-speaking six-grade students took a multi-trial L2 (English) word learning task after being exposed to a set of familiar words that rhymed with the target words. Children's PA was measured at grade 3. Children with relatively poorer L1 PA and those with better L1 PA did not differ in identifying the forms of the new words. However, children with poorer L1 PA demonstrated reduced performance in naming pictures with labels that rhymed with the pre-exposure words than with labels that did not rhyme with the pre-exposure words. Children with better L1 PA were not affected by the recurring rime shared by the pre-exposure words and the target words. These findings suggest that poor L1 PA may impede L2 word learning via difficulty in abstracting phonological patterns away from L2 input to scaffold word learning.

DNA barcoding of shark meats identify species composition and CITES-listed species from the markets in Taiwan.

BACKGROUND: An increasing awareness of the vulnerability of sharks to exploitation by shark finning has contributed to a growing concern about an unsustainable shark fishery. Taiwan's fleet has the 4th largest shark catch in the world, accounting for almost 6% of the global figures. Revealing the diversity of sharks consumed by Taiwanese is important in designing conservation plans. However, fins make up less than 5% of the total body weight of a shark, and their bodies are sold as filets in the market, making it difficult or impossible to identify species using morphological traits. METHODS: In the present study, we adopted a DNA barcoding technique using a 391-bp fragment of the mitochondrial cytochrome oxidase I (COI) gene to examine the diversity of shark filets and fins collected from markets and restaurants island-wide in Taiwan. RESULTS: Amongst the 548 tissue samples collected and sequenced, 20 major clusters were apparent by phylogenetic analyses, each of them containing individuals belonging to the same species (most with more than 95% bootstrap values), corresponding to 20 species of sharks. Additionally, Alopias pelagicus, Carcharhinus falciformis, Isurus oxyrinchus, and Prionace glauca consisted of 80% of the samples we collected, indicating that these species might be heavily consumed in Taiwan. Approximately 5% of the tissue samples used in this study were identified as species listed in CITES Appendix II, including two species of Sphyrna, C. longimanus and Carcharodon carcharias. CONCLUSION: DNA barcoding provides an alternative method for understanding shark species composition when species-specific data is unavailable. Considering the global population decline, stock assessments of Appendix II species and highly consumed species are needed to accomplish the ultimate goal of shark conservation.

Subfemtosecond hybrid synchronization between ultrafast Yb and Er fiber laser systems by controlling the relative injection timing.

We report experimental as well as theoretical investigation of the key factors that influence the relative timing jitter between hybrid synchronized ultrafast Yb and Er fiber laser systems. Experimental results show that, within the achievable synchronization range, the synchronization performance varies significantly with the relative injection timing between the 1 µm master and 1.5 µm slave pulses. This observation is in agreement with the insights obtained from the theoretical analysis, which identifies the retiming effect as a function of the initial condition of the master-slave pulse collision. By controlling the relative injection timing with a low-bandwidth intracavity feedback, relative timing jitter as low as 0.87 fs (within 1.9 MHz bandwidth) is successfully obtained.

Mode conversion using optical analogy of shortcut to adiabatic passage in engineered multimode waveguides.

A shortcut to adiabatic mode conversion in multimode waveguides using optical analogy of stimulated Raman adiabatic passage is investigated. The design of mode converters using the shortcut scheme is discussed. Computer-generated planar holograms are used to mimic the shaped pulses used to speed up adiabatic passage in quantum systems based on the transitionless quantum driving algorithm. The mode coupling properties are analyzed using the coupled mode theory and beam propagation simulations. We show reduced device length using the shortcut scheme as compared to the common adiabatic scheme. Modal evolution in the shortened device indeed follows the adiabatic eigenmode exactly amid the violation of adiabatic criterion.

Influence of charge on FITC-BSA-loaded chondroitin sulfate-chitosan nanoparticles upon cell uptake in human Caco-2 cell monolayers.

BACKGROUND AND METHODS: Chondroitin sulfate-chitosan (ChS-CS) nanoparticles and positively and negatively charged fluorescein isothiocyanate-conjugated bovine serum albumin (FITC-BSA)-loaded ChS-CS nanoparticles were prepared and characterized. The properties of ChS-CS nanoparticles, including cellular uptake, cytotoxicity, and transepithelial transport, as well as findings on field emission-scanning electron microscopy, transmission electron microscopy, and confocal laser scanning microscopy were evaluated in human epithelial colorectal adenocarcinoma (Caco-2) fibroblasts. ChS-CS nanoparticles with a mean particle size of 250 nm and zeta potentials ranging from -30 to +18 mV were prepared using an ionic gelation method. RESULTS: Standard cell viability assays demonstrated that cells incubated with ChS-CS and FITC-BSA-loaded ChS-CS nanoparticles remained more than 95% viable at particle concentrations up to 0.1 mg/mL. Endocytosis of nanoparticles was confirmed by confocal laser scanning microscopy and measured by flow cytometry. Ex vivo transepithelial transport studies using Caco-2 cells indicated that the nanoparticles were effectively transported into Caco-2 cells via endocytosis. The uptake of positively charged FITC-BSA-loaded ChS-CS nanoparticles across the epithelial membrane was more efficient than that of the negatively charged nanoparticles. CONCLUSION: The ChS-CS nanoparticles fabricated in this study were effectively endocytosed by Caco-2 fibroblasts without significant cytotoxicity at high nanoparticle concentrations. ChS-CS nanoparticles represent a potential novel delivery system for the transport of hydrophilic macromolecules.

Passively cascade-pulsed erbium ZBLAN all-fiber laser.

We propose and numerically demonstrate a cascade pulsing mechanism in a CW-pumped Er³âº:ZBLAN all-fiber laser system. In the design, the laser was pumped at 980 nm and passively Q-switched at 1.6 µm. The Q-switched resonance reduced the population on 4/13/2 of the erbium gain fiber, thereby creating a population inversion between the levels of 4/11/2 and 4/13/2, and instantly inducing an intense gain-switched pulse at 2.7 µm. Sequential 2.7-µm single-mode pulsing with a pulse energy of 170 µJ and a peak power of 6 kW was achieved with an absorbed pump power of 0.65 W.

Studies on a novel gelatin sponge: preparation and characterization of cross-linked gelatin scaffolds using 2-chloro-1-methylpyridinium iodide as a zero-length cross-linker.

We prepared a novel porous gelatin (GEL) sponge which was cross-linked (CL) with a zero-length crosslinker of 2-chloro-1-methylpyridinium iodide (CMPI), and compared CPMI with 1-ethyl-3,3-dimethylaminoproplycarbodiimide (EDC). The ninhydrin assay indicated that the CMPI-CL-GEL sponge had a higher degree of cross-linking than the EDC-CL-GEL sponge at cross-linking saturation. In contrast, the EDC-CL-GEL sponge demonstrated poor water uptake and a much slower enzymatic degradation rate than the CMPI-CL-GEL sponge. Scanning electron microscopy (SEM) images of the gelatin sponge fabricated using a gradient frozen-lyophilization method showed uniformly distributed and interconnected pores. Human 3T3 fibroblasts were successfully seeded onto the scaffolds, and cell proliferation was sustained on all CL-GEL sponges. CMPI-CL-GEL sponges demonstrated significantly increased cell numbers after day 1, and cell numbers steadily rose from day 1 to 12. Meanwhile, the CMPI-CL-GEL sponge had a higher cell number than the EDC-CL-GEL sponge (P < 0.05) by day 4. In vitro studies with 3T3 fibroblasts demonstrated an increased cell viability for those cells grown on sponges cross-linked with CMPI compared to those cross-linked with EDC. SEM images revealed attachment and spreading of cells, the CMPI-CL-GEL sponges had more cells that had elongated, migrated, and formed interconnected networks with neighboring cells.

The comparison of protein-entrapped liposomes and lipoparticles: preparation, characterization, and efficacy of cellular uptake.

Fluorescein isothiocyanate-conjugated bovine serum albumin (FITC-BSA)-loaded polyethylene glycol (PEG)-modified liposomes and lipoparticles with high protein entrapment were developed. The lipid formula of the liposomes contained PEGylated lipids and unsaturated fatty acids for enhancing membrane fluidity and effective delivery into cells. The preparation techniques, lipid content, and PEG-modified lipoparticle ratios were evaluated. The PEG-modified lipoparticles prepared by ethanol injection extrusion (100 nm pore size) achieve a population of blank liposomes with a mean size of 125 ± 2.3 nm and a zeta potential of -12.4 ± 1.5 mV. The average particle size of the PEG-modified lipoparticles was 133.7 ± 8.6 nm with a zeta potential of +13.3 mV. Lipoparticle conformation was determined using transmission electron microscopy and field-emission scanning electron microscopy. The FITC-BSA encapsulation efficiency was dramatically increased from 19.0% for liposomes to 59.7% for lipoparticles. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) results confirmed the preparation process, and an 8-hour leaching test did not harm the protein structure. Once prepared, the physical and chemical stability of the PEG-modified lipoparticle formulations was satisfactory over 90 days. In vitro retention tests indicated that the 50% retention time for the protein-containing lipoparticles was 7.9 hours, substantially longer than the liposomes at 3.3 hours. A Caco-2 cell model was used for evaluating the cytotoxicity and cell uptake efficiency of the PEG-modified lipoparticles. At a lipid content below 0.25 mM, neither the liposomes nor the lipoparticles caused significant cellular cytotoxicity (P < 0.01) and FITC-BSA was significantly taken up into cells within 60 minutes (P < 0.01).

Novel protein-loaded chondroitin sulfate-chitosan nanoparticles: preparation and characterization.

In this study, the potential of chondroitin sulfate (ChS)-chitosan (CS) nanoparticles (NPs) for the delivery of proteins was investigated. ChS-CS NPs were prepared by ionic cross-linking of CS solution with ChS. The aggregation line, particle size and zeta potential were investigated as a function of the pH, weight ratio and concentration. The water content and formation yield of the NPs were measured by gravimetry. Results indicated that ChS-CS NPs showed a higher degree of ionic cross-linking and formation yield than sodium tripolyphosphate-CS NPs. Fluorescein isothiocyanate conjugate bovine serum albumin (FITC-BSA), a model protein drug, was incorporated into the ChS-CS NPs. The encapsulation efficiency was obviously increased with the increase in initial FITC-BSA concentration and was as high as 90%. In vitro release studies of ChS-CS NPs showed a small burst effect following a continued and controlled release. Cytotoxicity tests with Caco-2 cells showed no toxic effects of ChS-CS NPs. The ex vivo cellular uptake studies using Caco-2 and HEK-293 cells indicated that NPs were found to be endocytosed into the cells. In conclusion, ChS-CS NPs are a potential new delivery system for the transport of hydrophilic compounds such as proteins.