Comparison of Alginate Mixtures as Wall Materials of Schizochytrium Oil Microcapsules Formed by Coaxial Electrospray.

This work evaluated maltodextrin/alginate and ß-glucan/alginate mixtures in the food industry as wall materials for the microencapsulation of Schizochytrium sp. oil, an important source of the omega-3 fatty acid DHA (docosahexaenoic acid). Results showed that both mixtures display a shear-thinning behavior, although the viscosity is higher in ß-glucan/alginate mixtures than in maltodextrin/alginate. Scanning electron microscopy was used to assess the morphology of the microcapsules, which appeared more homogeneous for maltodextrin/alginate. In addition, oil-encapsulation efficiency was higher in maltodextrin/alginate mixtures (90%) than in ß-glucan/alginate mixtures (80%). Finally, evaluating the microcapsules' stability by FTIR when exposed to high temperature (80 °C) showed that maltodextrin/alginate microcapsules were not degraded contrary to the ß-glucan/alginate microcapsules. Thus, although high oil-encapsulation efficiency was obtained with both mixtures, the microcapsules' morphology and prolonged stability suggest that maltodextrin/alginate is a suitable wall material for microencapsulation of Schizochytrium sp. oil.

Large Peritoneal Macrophages and Transitional Premonocytes Promote Survival during Abdominal Sepsis.

Monocytes and macrophages are early sentinels of infection. The peritoneum contains two resident populations: large and small peritoneal macrophages (LPMs and SPMs). While LPMs self-renew, circulating monocytes enter the peritoneum and differentiate into SPMs. We lack information on the dynamics of monocyte-macrophage trafficking during abdominal sepsis, reflecting an important knowledge gap. In this study, we characterize the presence of LPMs, SPMs, and monocytes in the peritoneum of mice following cecal ligation and puncture (CLP)-induced sepsis and sham surgery. LPMs rapidly disappeared from the peritoneum and were scarce at 18-66 h after CLP or sham surgery. By 14 d, LPMs returned for sham mice, but they remained scarce in CLP mice. Depletion of LPMs from the peritoneum of CD11b-DTR mice greatly increased animal mortality. These data imply that LPMs are critical for sepsis survival. Monocytes rapidly infiltrated the peritoneum and were abundant at 18-66 h after CLP or sham surgery. Surprisingly, SPMs only increased at 14 d post-CLP. Therefore, monocytes may defend hosts from acute sepsis mortality without generating SPMs. More monocytes were present in mice predicted to survive sepsis versus mice predicted to die. However, altering monocyte numbers via CCR2 deficiency or adoptive transfer did not significantly affect animal survival. We reasoned that animals destined to survive sepsis may exhibit a different monocyte phenotype, rather than merely enhanced numbers. Indeed, mice predicted to survive possessed more CD31+, CXCR4hi transitional premonocytes in their abdomen. Inhibition of CXCL12-CXCR4 signaling via AMD3100 exacerbated sepsis. These data imply that recruitment of transitional premonocytes to the abdomen promotes sepsis survival.

Impact of CTLA-4 blockade in conjunction with metronomic chemotherapy on preclinical breast cancer growth.

BACKGROUND: Although there are reports that metronomic cyclophosphamide (CTX) can be immune stimulating, the impact of its combination with anti-CTLA-4 immunotherapy for the treatment of cancer remains to be evaluated. METHODS: Murine EMT-6/P breast cancer, or its cisplatin or CTX-resistant variants, or CT-26 colon, were implanted into Balb/c mice. Established tumours were monitored for relative growth following treatment with anti-CTLA-4 antibody alone or in combination with; (a) metronomic CTX (ldCTX; 20 mg kg-1 day-1), b) bolus (150 mg kg-1) plus ldCTX, or (c) sequential treatment with gemcitabine (160 mg kg-1 every 3 days). RESULTS: EMT-6/P tumours responded to anti-CTLA-4 therapy, but this response was less effective when combined with bolus plus ldCTX. Anti-CTLA-4 could be effectively combined with either ldCTX (without a bolus), or with regimens of either sequential or concomitant gemcitabine, including in orthotopic EMT-6 tumours, and independently of the schedule of drug administration. Tumour responses were confirmed with CT-26 tumours but were less pronounced in drug-resistant EMT-6/CTX or EMT-6/DDP tumour models than in the parent tumour. A number of tumour bearing mice developed spontaneous metastases under continuous therapy. The majority of cured mice rejected tumour re-challenges. CONCLUSIONS: Metronomic CTX can be combined with anti-CTLA-4 therapy, but this therapy is impaired by concomitant bolus CTX. Sequential therapy of anti-CTLA-4 followed by gemcitabine is effective in chemotherapy-naive tumours, although tumour relapses can occur, in some cases accompanied by the development of spontaneous metastases.

Identification of Bioactivity, Volatile and Fatty Acid Profile in Supercritical Fluid Extracts of Mexican arnica.

Supercritical fluid extraction (SFE) is a sustainable technique used for the extraction of lipophilic metabolites such as pigments and fatty acids. Arnica plant is considered a potential candidate material with high antioxidant and antimicrobial activities. Therefore, in this study, a locally available Heterotheca inuloides, also known as Mexican arnica, was analyzed for the extraction of high-value compounds. Based on different pressure (P), temperature (T), and co-solvent (CoS), four treatments (T) were prepared. A maximum 7.13% yield was recovered from T2 (T = 60 °C, P = 10 MPa, CoS = 8 g/min), followed by 6.69% from T4 (T = 60 °C, P = 30 MPa, CoS = 4 g/min). Some bioactive sesquiterpenoids such as 7-hydroxycadalene, caryophyllene and δ-cadinene were identified in the extracts by GC/MS. The fatty acid profile revealed that the main components were palmitic acid (C16:0), followed by linoleic acid (C18:2ω6c), α-linolenic acid (C18:3ω3) and stearic acid (C18:0) differing in percent yield per treatment. Antibacterial activities were determined by the agar diffusion method, indicating that all the treatments exerted strong antibacterial activity against S. aureus, C. albicans, and E. coli strains. The antioxidant capacity of the extracts was also measured by three in vitro assays, DPPH, TEAC and FRAP, using Trolox as a standard. Results showed high antioxidant capacity enabling pharmaceutical applications of Mexican arnica.