Chemoradiotherapy for Inoperable Carotid Body Leiomyosarcoma: A Case Report and Review of Literature.

Vascular leiomyosarcoma is an extremely rare tumor and is associated with poor prognosis among leiomyosarcoma. Surgical resection remains the main treatment option. But outcome of definitive treatment with chemoradiotherapy in inoperable patients is not clear. Here, we report treatment and outcome of definitive chemoradiotherapy in a case of vascular leiomyosarcoma. A 64-year-old man with the initial presentation of pulsatile right neck mass was diagnosed with right carotid body leiomyosarcoma. He refused surgical intervention due to risk of carotid body injury and ischemic stroke. Successful tumor control was achieved with carboplatin-based concurrent chemoradiotherapy. Investigational liquid biopsy for circulating sarcoma cells was also performed to analyze drug sensitivity profile of this rare tumor. One year after treatment, the disease remained well controlled and there was no evidence of baroreflex failure or treatment-related late toxicities. To our best knowledge, this is the first case report of right carotid body leiomyosarcoma controlled with definitive concurrent chemoradiotherapy. The approach of personalized multi-modality treatment will be a focus of our future investigation.

Characterization of collagen from haddock skin and wound healing properties of its hydrolysates.

Collagen, one of the most abundant structural proteins found in vertebrates, has been extensively used for biomedical applications. The objectives of this study were to isolate and characterize acid-soluble collagen (ASC) from haddock (Melanogrammus aeglefinus) skins and to investigate the biological function of ASC hydrolysates in wound healing. Amino acid composition, SDS-PAGE and FTIR suggested that the ASC is most likely type I collagen with well-maintained helical structures. Both the denaturation and shrinkage temperatures of ASC isolated from haddock skins were lower than those of mammalian collagens. The average molecular weights of hydrolysates decreased with the increase in HCl concentration as well as hydrolysis times. ASC and hydrolysates with more molecules (53.8 kDa) decreased the bleeding and clotting times and promoted order 2 vessel formation effectively. All the experimental groups, including the ASC group and its hydrolysate groups, could accelerate epithelialization and shorten the wound healing time of mice. The ASC from haddock skin could therefore serve as an alternative collagen for skin wound healing.

Proteinuria can predict short-term prognosis in critically ill cirrhotic patients.

BACKGROUND AND AIM: Increasing evidence supports that proteinuria is a useful tool in several clinical situations. Cirrhotic patients with proteinuria admitted to intensive care units (ICUs) have high mortality rates. This study analyzed the outcomes of critically ill cirrhotic patients and determined the prognostic value of proteinuria. METHODS: A total of 230 cirrhotic patients were admitted to the ICU of a hospital in Taiwan between March 2008 and February 2011. We prospectively collected data, including demographic parameters and clinical characteristics, of patients on day 1 of admission to the ICU and analyzed these variables as predictors of mortality. RESULTS: The overall ICU, hospital, and 90-day mortality rates were 54%, 60%, and 63%, respectively. The patients with proteinuria had higher rates of acute kidney injury (84% vs. 53%, P<0.001), ICU death (60% vs. 25%, P<0.001), and 90-day mortality (79% vs. 40%, P<0.001). Patients with proteinuria had a hazard ratio for 90-day mortality of 2.800 (P<0.001; 95% CI, 1.927-4.069). Multivariate analysis showed that proteinuria and the Sequential Organ Failure Assessment score were predictors of short-term prognosis. CONCLUSIONS: Proteinuria in critically ill cirrhotic patients is associated with increased complications of liver cirrhosis, ICU mortality, and poor short-term prognosis.

Chitosan acetate as an active coating material and its effects on the storing of Prunus avium L.

In this article, chitosan acetate (CA) was prepared by the method of solid-liquid reaction. CA was a stable faint yellow powder with water solubility. CA kept the same backbone in the chemical structure as the raw material of chitosan, and it also had the similar antibacterial properties with chitosan. CA could form a coating film on the outside surface of the sweet cherries, could effectively retard the loss of the water, titratable acidity, and ascorbic acid of sweet cherries, and could induce a significant increase in the peroxidase and catalase activities in the fruit. The CA coating could also increase the ratio of the total soluble solids and titratable acidity in the fruit. The application of CA effectively maintained quality attributes and extended postharvest life of the sweet cherries. The results revealed that the CA salts had potential application in active edible coating materials in the storage of fresh fruit.

Preparation and characteristics of chitosan microspheres in different acetylation as drug carrier system.

Chitosan microspheres (CM) and reacetylated chitosan microspheres (ACM) were successfully made by the methods of oil/water emulsification and acetic anhydride. The characteristics of the microspheres as a drug carrier system were investigated. Two microsphere samples had spherical shape with the mean diameter of 80.79 microm for CM and 81.25 microm for ACM. The in vitro degradation (pH 7.4) in the presence of lysozyme showed a slow mass loss and ACM was higher degradation compared to CM. The microspheres, especially ACM, had a high drug loading capacity of Adriamycin hydrochloride (ADM) (12.4%) and had sustained release. The cytotoxicity was evaluated in vitro via MTT assay, ACM with steadily continual adhesion to cells had no fibroblast cytotoxicity. The inhibitory rates of ADM-loading CM, ACM suspension to Tca 8113 cells were significantly outperformed that of ADM solution.

Oleoyl-chitosan nanoparticles inhibits Escherichia coli and Staphylococcus aureus by damaging the cell membrane and putative binding to extracellular or intracellular targets.

A novel chitosan antibacterial dispersion system was prepared by oleoyl-chitosan (OCS) nanoparticles (OCNP). We further investigated the antimicrobial mode of OCNP against Escherichia coli and Staphylococcus aureus using a combination of approaches, including measurement of the effect of lecithin and phosphate groups, the conformation of membrane protein, internalization of fluorescein isothiocyanate (FITC)-labeled OCS nanoparticles (FITC-OCS nanoparticles) observed under fluorescence microscopy and DNA/RNA binding assay. Results of fluorescence experiments indicated that OCNP influenced the structure of bacterial membranes. The lecithin effect showed that OCNP bound to cytoplasmic membrane phospholipids of S. aureus, and phosphate groups played an important role. Fluorescence microscopy observations demonstrated that the way OCNP entered into bacteria varied against strains. The gel-retardation experiment showed that OCNP bound strongly to DNA/RNA and retarded their migration in the gels in a concentration-dependent manner. These results indicate that OCNP exerts its antibacterial activity by damaging the structures of cell membrane and putative binding to extracellular targets such as phosphate groups or intracellular targets such as DNA and RNA.

Injectable thermosensitive hydrogel based on chitosan and quaternized chitosan and the biomedical properties.

A novel injectable thermosensitive hydrogel (CS-HTCC/alpha beta-GP) was successfully designed and prepared using chitosan (CS), quaternized chitosan (HTCC) and alpha,beta-glycerophosphate (alpha,beta-GP) without any additional chemical stimulus. The gelation point of CS-HTCC/alpha beta-GP can be set at a temperature close to normal body temperature or other temperature above 25 degrees C. The transition process can be controlled by adjusting the weight ratio of CS to HTCC, or different final concentration of alpha,beta-GP. The optimum formulation is (CS + HTCC) (2% w/v), CS/HTCC (5/1 w/w) and alpha,beta-GP 8.33% or 9.09% (w/v), where the sol-gel transition time was 3 min at 37 degrees C. The drug released over 3 h from the CS-HTCC/alpha,beta-GP thermosensitive hydrogel in artificial saliva pH 6.8. In addition, CS-HTCC/alpha,beta-GP thermosensitive hydrogel exhibited stronger antibacterial activity towards two periodontal pathogens (Porphyromonas gingivalis, P.g and Prevotella intermedia, P.i). CS-HTCC/alpha, beta-GP thermosensitive hydrogel was a considerable candidate as a local drug delivery system for periodontal treatment.

Biological evaluation of a novel chitosan-PVA-based local delivery system for treatment of periodontitis.

In the study, we intend to design a suitable localized drug delivery system (LDDS) with chitosan and poly vinyl alcohol (PVA) for treating serve periodontitis. For that, a novel formulation based on the incorporation of chitosan-based microspheres into PVA film was prepared. As the core parts of the novel formulation, chitosan-based microspheres were prepared form chitosan and/or carboxymethyl-chitosan (CM-chitosan) by using water-in-oil emulsification method. Then basic in vitro and in vivo experiments focusing on biocompatibility and biodegradability of the two chitosan-based microspheres were carried out to evaluate the feasibility of the novel LDDS. In vitro tests, besides having no hemolysis, chitosan microsphere (Cs1-Ms), and CM-chitosan microsphere (Cs2-Ms) have adsorbed little proteins on their surfaces. Moreover, plasma proteins adsorbed on Cs2-Ms, most of which can easily desorbed, are much less than that adsorbed on Cs1-Ms. This indicates that Cs2-Ms perhaps has better biocompatibility than Cs1-Ms. In vivo tests, Cs1-Ms and Cs2-Ms were subcutaneously implanted in rat to investigate the host tissue inflammatory response. Implantations of Cs1-Ms and Cs2-Ms induced a little more severe inflammation when compared with the implantation of PVA film. However, the difference on in vivo biocompatibility between Cs1-Ms and Cs2-Ms could not be confirmed by the implantation model of our experiments. Both Cs1-Ms and Cs2-Ms had suffered bioerosion when they were subcutaneously implanted. The hard and compact matrixes of Cs1-Ms were degraded very slowly, and only some trifling degradation had been found until 4 weeks of implantation. In contrast, Cs2-Ms is soft and more hydrophilic, and can be quickly degraded in a form of diffluence by the physiological circumstance. All these results suggested that Cs2-Ms had better potentials used as core parts of the novel designed LDDS in the future developments.

Investigation of polymeric amphiphilic nanoparticles as antitumor drug carriers.

In this paper, polymeric amphiphilic nanoparticles based on oleoyl-chitosan (OCH) with different degrees of substitution (DS, 5%, 11% and 27%) were prepared by Oil/Water emulsification method. Mean diameters of the nanoparticles were 327.4 nm, 255.3 nm and 192.6 nm, respectively. Doxorubicin (DOX) was efficiently loaded into OCH nanoparticles and provided a sustained released after a burst release in PBS. These nanoparticles showed no cytotoxicity to mouse embryo fibroblasts (MEF) and low hemolysis rates (<5%). The results of SDS-PAGE indicated that bovine calf serum (BCS) adsorption on OCH nanoparticles was inhibited by smaller particle size. Cellular uptake was evaluated by incubating fluorescence labeled OCH nanoparticles with human lung carcinoma cells (A549) and mouse macrophages (RAW264.7). Cellular uptake of OCH nanoparticles was time--and concentration--dependent. Finding the appropriate incubation time and concentration of OCH nanoparticles used as drug carriers might decrease phagocytic uptake, increase cancer cell uptake and ultimately improve therapeutic efficiency of antitumor therapeutic agents.

Microencapsulation of a probiotic bacteria with alginate-gelatin and its properties.

Lactobacillus casei ATCC 393-loaded microcapsules based on alginate and gelatin had been prepared by extrusion method and the product could increase the cell numbers of L. casei ATCC 393 to be 10(7) CFU g(-1) in the dry state of microcapsules. The microparticles homogeneously distributed with size of 1.1 ± 0.2 mm. Four kinds of microcapsules (S(1), S(2), S(3) and S(4)) exhibited swelling in simulated gastric fluid (SGF) while the beads eroded and disintegrated rapidly in simulated intestinal fluid (SIF). Cells of L. casei ATCC 393 could be continuously released from the microcapsules during simulated gastrointestinal tract (GIT) and the release amounts and speeds in SIF were much higher and faster than that in SGF. Encapsulation in alginate-gelatin microcapsules successfully improved the survival of L. casei ATCC 393 and this approach might be useful in delivery of probiotic cultures as a functional food.

Antibacterial mechanism of chitosan microspheres in a solid dispersing system against E. coli.

In this study, we investigated the antibacterial mechanism through the interfacial contacting inhibition behaviors of chitosan antimicrobials against Escherichia coli in solid dispersing state. Chitosan microspheres (CMs) were prepared by emulsification cross-linking reaction, and oleoyl-CMs (OCMs) were obtained by introduction of oleoyl groups to the chitosan. The CMs were with smooth surface and spherical shape of diameter of about 124 microm. The antibacterial activity was directly proportional to the concentration and the hydrophobic property of CMs. The fluorescence experiments indicated CMs had influenced the structure of membrane, especially the OCMs were speculated to interact with proteins on the cell membrane. SEM photographs showed E. coli adhered to the surface of the CMs and provided evidences for the disruption of the cells, while the bacterium conglomerated on the surface of the OCMs. The CMs changed the permeability of membrane and caused cellular leakage that correlated with the hydrophobic interaction between CMs and cytoplasmic membrane phospholipids of Gram-negative bacteria. Solid dispersing system makes the antibacterial activities of CMs counted as a sequent event-driven to study the antibacterial mechanism of chitosan originally.

Uptake of oleoyl-chitosan nanoparticles by A549 cells.

The aim of the present study was to evaluate cellular uptake of oleoyl-chitosan (OCH) nanoparticles by using A549 cells, a human lung carcinoma cell line, for drug and gene delivery applications. In this study, self-assembled OCH nanoparticles encapsulating a fluorescent marker molecule, fluorescein isothiocyanate (FITC), were prepared and characterized. The effects of particle size, concentration, and incubation time on the cellular uptake of the nanoparticles (FITC-OCH nanoparticles) were quantified by spectrofluorometric measurement and confirmed using fluorescence microscopy studies. The nanoparticles were taken up by the cells, and levels of binding and uptake increased with the decrease of particle size and the increase of particle concentration and incubation time. These results implied that the OCH nanoparticles have great potential to be applied as a drug carrier system to deliver drugs into the cells.

Plasma protein adsorption pattern and tissue-implant reaction of poly(vinyl alcohol)/carboxymethyl-chitosan blend films.

Various poly(vinyl alcohol)/carboxymethyl-chitosan (PVA/CMCS) blend films were prepared by a mechanical blending method and characterized by SEM for their surface and cross-section morphologies. It indicated that blending high CMCS content in PVA plastic led to a rough surface and loose structure. Bovine serum albumin (BSA) and bovine fibrinogen (BFG) were chosen as representative plasma proteins to carry out adsorption tests. Equilibrium adsorption amount of proteins onto the blends decreased with the increase of CMCS content in film matrix, and BSA was more easily adsorbed onto the films than BFG in the same conditions. The blend films also exhibited different trends for BSA and BFG adsorption when pH of the media changed, but maximum adsorption approximately occurred at the isoelectric point of proteins. Moreover, increasing the ionic strength would always decrease the adsorptions of protein onto the films. In animal experiments, it was found that incorporation of CMCS and PVA gave a lower tissue reaction than pure PVA films when they were subcutaneously implanted in Wistar rats. After two weeks subcutaneous implantation, surfaces of PVA became wrinkled and cracked; however, the blend implants exhibited a alveolate porous microstructure.

Preparation and blood coagulation evaluation of chitosan microspheres.

Cross-linked chitosan microspheres (40-100 microm) with smooth surface were prepared by the methods of emulsification and ethanol coagulant. FTIR results showed that the cross-linking reaction occurred on the amino groups of chitosan molecules. The swelling characteristic of chitosan microspheres was influenced by the environment pH, being generally greater at low rather than higher pH values. The coagulation properties of chitosan microspheres were evaluated by dynamic blood clotting, platelet adhesion and activation, erythrocyte adhesion, hemolysis, and protein absorption assays. Chitosan microspheres can shorten the clotting time and induce the adhesion and activation of platelets. But the shortening of clotting time by chitosan microspheres may be related to not only platelet aggregation, but also erythrocyte aggregation. Take together, chitosan microspheres may be potential use as thrombospheres.

Self-assembled nanoparticles based on hydrophobically modified chitosan as carriers for doxorubicin.

In this study self-assembled nanoparticles based on oleoyl-chitosan (OCH) were prepared with a mean diameter of 255.3 nm and an almost spherical shape. The toxicity profile of OCH nanoparticles was evaluated in vitro via hemolysis test and MTT assay. The hemolysis rates of OCH nanoparticles tested in different conditions came well within permissible limits (5%). The OCH nanoparticles showed no cytotoxicity to mouse embryo fibroblasts. Doxorubicin (DOX) was efficiently loaded into OCH nanoparticles with an encapsulation efficiency of 52.6%. The drug was rapidly and completely released from the nanoparticles (DOX-OCH nanoparticles) at pH 3.8, whereas at pH 7.4 there was a sustained release after a burst release. The inhibitory rates of DOX-OCH nanoparticle suspension to different human cancer cells (A549, Bel-7402, HeLa, and SGC-7901) significantly outperformed that of DOX solution. These results revealed the potential of OCH nanoparticles as carriers for hydrophobic antitumor agents.

Effect of the molecular mass and degree of substitution of oleoylchitosan on the structure, rheological properties, and formation of nanoparticles.

Oleoylchitosans (O-chitosans), with different molecular masses and degrees of substitution (DS), were synthesized by reacting chitosan with oleoyl chloride. The FT-IR suggested the formation of an amide linkage between amino groups of chitosan and carboxyl groups of oleic acid. The viscosity of O-chitosan sharply increased with the increase of concentration, whereas that of unmodified chitosan rose only slightly. This increase was stronger as the increase of hydrophobicity (DS) and molecular mass of the polymer. The critical aggregation concentration (CAC) of O-chitosans with DS 5, 11, and 27% were 79.43, 31.6, 10 mg/L, respectively, and the CAC of samples with molecular masses of 20, 38, 300, and 1100 kDa were 50.1, 74.93, 125.9, and 630.9 mg/L, respectively. All of the O-chitosans could reduce surface tension slightly. Nanoparticles were prepared using an O/W emulsification method. Mean diameters of the polymeric amphiphilic nanoparticles of O-chitosans with DS 5 and 11% were around 327.4 and 275.3 nm, respectively.

Cellulose acetate/chitosan multimicrospheres preparation and ranitidine hydrochloride release in vitro.

A noval cellulose acetate/chitosan multimicrospheres (CACM) was prepared by the method of w/o/w emulsion. The concentration of cellulose acetate (CA) and the ratio of CA/chitosan (CS) had influence on the CACM size, and appearance. Ranitidine hydrochloride loading, and releasing efficiency in vitro were investigated. The optimal condition for preparation of the microspheres was CA concentration at 2% and the ratio of CA/CS at 3/1. The microspheres size was 200-350 microm. The appearance of microspheres was spherical, porous, and nonaggregated. The highest loading efficiency was 21%. The ranitidine release from the CACM was 40% during 48 hr in buffers.