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This paper revisits a recently introduced chemostat model of one-species with a periodic input of a single nutrient which is described by a system of delay differential equations. Previous results provided sufficient conditions ensuring the existence and uniqueness of a periodic solution for arbitrarily small delays. This paper partially extends these results by proving-with the construction of Lyapunov-like functions-that the evoked periodic solution is globally asymptotically stable when considering Monod uptake functions and a particular family of nutrient inputs.

Gallbladder cancer (GBC) is an aggressive and highly lethal disease with relatively low global incidence, but one that constitutes a major health problem in Asian and Latin American countries, particularly in Chile. The identification of new tumor-associated markers with potential prognosis value is required for GBC clinical practice. Using immunohistochemistry/tumor tissue microarray, we evaluated the expression of 17 gastrointestinal tumor-associated protein markers (CK7, CK17, CK19, CK20, CKLMW, CKHMW, MUC1, MUC2, MUC5AC, MUC6, CA125, CD10, CEA, vimentin, villin, claudin-4, and CDX2) in primary gallbladder adenocarcinomas from 180 Chilean patients and analyzed potential associations with their pathological and clinical characteristics. Younger female patients with well- to moderately differentiated tumors had a better prognosis than that of older female or male patients with tumors with a similar tumor differentiation grade. Among all analyzed markers, MUC6 expression was associated with better prognosis in patients with well- to moderately differentiated tumors, whereas CK17 or CD10 was associated with worse prognosis in patients with poorly differentiated tumors. In addition, the MUC6 + CK17 - expression pattern was strongly associated with better prognosis in patients with well- to moderately differentiated tumors, whereas patients with poorly differentiated tumors and with the CK17 + CD10 + expression pattern showed worse prognosis. Our results suggest that tumor MUC6, CK17, and CD10 can be considered as potential prognosis markers for GBC.

Background: Auscultation is a fundamental part of the physical examination, but its utility has been questioned due to the low inter-rater concordance. We therefore sought to evaluate the concordance of the discrimination of lung sound recordings between experienced physiotherapists., Methods: Lung sound recordings were selected and validated by an expert panel when Fleiss κ concordance was > 0.75. Eleven recordings were played for subject recognition using a portable computer in their workplace. Results were analyzed using Fleiss κ when looking for concordance between physiotherapists. Univariate regression was performed to determine if there was an association with clinical training, years of experience, academic accomplishment, or university affiliation., Results: Sixty-nine physiotherapists with a median of 4 years of working experience (interquartile range 2-6 y) completed the study. There was moderate concordance (κ = 0.562; 95% CI 0.462-0.605) for overall lung sound recording discrimination. For continuous and noncontinuous lung sound recordings, discrimination concordance was substantial (κ = 0.63 and κ = 0.76, respectively). A bivariate analysis revealed that years of experience presented an inverse association with stridor recognition., Conclusions: Concordance between physiotherapists in discriminating recorded lung sounds was moderate. The ability to recognize stridor was inversely associated with years of work experience., (Copyright © 2020 by Daedalus Enterprises.)

Ovarian epithelial carcinoma (OEC) is the most frequent ovarian tumor, characterized by a high mortality in advanced stages where conventional therapies are not effective. Based on the role of the immune system in the progression of this disease, immunotherapy using checkpoint blockade has been considered as a therapeutic alternative. Nevertheless, its results do not match up to the positive results in entities like melanoma and other malignancies, suggesting the need to find other therapies to be used alone or in combination. Dendritic cell- (DC-) based vaccines have shown promising results in several types of cancer, such as melanoma, prostate, and lung cancers, due to the essential role played by DCs in the activation of specific T cells, thus using other ways of activating the immune response than immune checkpoint blockade. During the last decade, we have used DC-based vaccines loaded with an allogeneic heat shock-conditioned melanoma cell lysate in the treatment of advanced stage patients in a series of clinical trials. In these studies, 60% of treated patients showed immunological responses which correlated positively with improved survival. Considering the relevance of ovarian cancer and the promising results of our DC-based vaccine, we show here that heat shock-conditioned cell lysates derived from ovarian epithelial carcinoma cell lines have the potential to induce the phenotypic and functional maturation of human DC, which in turn, is able to induce an efficient CD4 + and CD8 + T cell-mediated immune responses against ovarian cancer cell lines in vitro . In summary, OEC heat shock-conditioned cell lysate-loaded DCs may be considered for future combined immunotherapy approaches against ovarian tumors., Competing Interests: The authors declare that they have no conflict of interest., (Copyright © 2019 Iván Flores et al.)

Immunotherapy based on checkpoint blockers has proven survival benefits in patients with melanoma and other malignancies. Nevertheless, a significant proportion of treated patients remains refractory, suggesting that in combination with active immunizations, such as cancer vaccines, they could be helpful to improve response rates. During the last decade, we have used dendritic cell (DC) based vaccines where DCs loaded with an allogeneic heat-conditioned melanoma cell lysate were tested in a series of clinical trials. In these studies, 60% of stage IV melanoma DC-treated patients showed immunological responses correlating with improved survival. Further studies showed that an essential part of the clinical efficacy was associated with the use of conditioned lysates. Gallbladder cancer (GBC) is a high-incidence malignancy in South America. Here, we evaluated the feasibility of producing effective DCs using heat-conditioned cell lysates derived from gallbladder cancer cell lines (GBCCL). By characterizing nine different GBCCLs and several fresh tumor tissues, we found that they expressed some tumor-associated antigens such as CEA, MUC-1, CA19-9, Erb2, Survivin, and several carcinoembryonic antigens. Moreover, heat-shock treatment of GBCCLs induced calreticulin translocation and release of HMGB1 and ATP, both known to act as danger signals. Monocytes stimulated with combinations of conditioned lysates exhibited a potent increase of DC-maturation markers. Furthermore, conditioned lysate-matured DCs were capable of strongly inducing CD4 + and CD8 + T cell activation, in both allogeneic and autologous cell co-cultures. Finally, in vitro stimulated CD8 + T cells recognize HLA-matched GBCCLs. In summary, GBC cell lysate-loaded DCs may be considered for future immunotherapy approaches.

Background: Gallbladder cancer (GBC), although infrequent in industrialized countries, has high incidence rates in certain world regions, being a leading cause of death among elderly Chilean women. Surgery is the only effective treatment, and a five-year survival rate of advanced-stage patients is less than 10%. Hence, exploring immunotherapy is relevant, although GBC immunogenicity is poorly understood. This study examined the relationship between the host immune response and GBC patient survival based on the presence of tumor-infiltrating lymphocytes at different disease stages., Methods: Tumor tissues from 80 GBC patients were analyzed by immunohistochemistry for the presence of CD3 + , CD4 + , CD8 + , and Foxp3 + T cell populations, and the results were associated with clinical stage and patient survival., Results: The majority of tumor samples showed CD3 + T cell infiltration, which correlated with better prognosis, particularly in advanced disease stages. CD8 + , but not CD4 + , T cell infiltration correlated with improved survival, particularly in advanced disease stages. Interestingly, a < 1 CD4 + /CD8 + T cell ratio was related with increased survival. Additionally, the presence of Foxp3 + T cells correlated with decreased patient survival, whereas a ≤ 1 Foxp3 + /CD8 + T cell ratio was associated with improved patient survival., Conclusions: Depending on the disease stage, the presence of CD8 + and absence of Foxp3 + T cell populations in tumor tissues correlated with improved GBC patient survival, and thus represent potential markers for prognosis and management of advanced disease, and supports testing of immunotherapy.

Background: Various hepatoprotective herbal products from plants are available in Mexico, where up to 85% of patients with liver disease use some form of complementary and alternative medicine. However, only few studies have reported on the biological evaluation of these products., Objective: Using a model of carbon tetrachloride (CCl4)-induced hepatotoxicity in rats, we evaluated the effects of commercial herbal extracts used most commonly in the metropolitan area of Monterrey, Mexico., Materials and Methods: The commercial products were identified through surveys in public areas. The effect of these products given with or without CCl4 in rats was evaluated by measuring the serum concentrations of aspartate amino transferase (AST) and alanine amino transferase (ALT), and histopathological analysis. Legalon(®) was used as the standard drug., Results: The most commonly used herbal products were Hepatisan(®) capsules, Boldo capsules, Hepavida(®) capsules, Boldo infusion, and milk thistle herbal supplement (80% silymarin). None of the products tested was hepatotoxic according to transaminase and histological analyses. AST and ALT activities were significantly lower in the Hepavida+CCl4-treated group as compared with the CCl4-only group. AST and ALT activities in the silymarin, Hepatisan, and Boldo tea groups were similar to those in the CCl4 group. The CCl4 group displayed submassive confluent necrosis and mixed inflammatory infiltration. Both the Hepatisan+CCl4 and Boldo tea+CCl4 groups exhibited ballooning degeneration, inflammatory infiltration, and lytic necrosis. The silymarin+CCl4 group exhibited microvesicular steatosis. The Hepavida+CCl4- and Legalon+CCL4-treated groups had lower percentages of necrotic cells as compared with the CCl4-treated group; this treatment was hepatoprotective against necrosis., Conclusion: Only Hepavida had a hepatoprotective effect.

Adverse reactions of acetaminophen have been associated to oxidative stress, which may be elicited by reactive oxygen species (ROS) and/or production of the metabolite NAPQI. Both phenomena would arise through the activity of liver cytochrome P450 (CYP450) system, but their contribution to this oxidative stress is yet to be clarified. A NADPH oxidase activity has been proposed in rat liver microsomes. This activity may be due to the presence of NAD(P)H oxidase (NOX) isoforms in liver endoplasmic reticulum. Both NOX and the CYP450 system activities can catalyze ROS generation using NADPH as a cofactor. Therefore, acetaminophen biotransformation, which requires NADPH, may promote ROS generation through either activity or both. To discriminate between these possibilities, rat liver microsomes were incubated with acetaminophen and NADPH in the presence or absence of specific inhibitors. Incubation with NADPH and acetaminophen elicited lipid peroxidation and decreased thiol content and glutathione-S-transferase (GST) activity. The NOX inhibitors apocynin and plumbagin prevented all these phenomena but the decrease in thiol content. In contrast, this decrease was completely prevented by the specific CYP450 system inhibitor SKF-525A. These data suggest that ROS generation following incubation of microsomes with acetaminophen and NADPH appears to be mainly caused by a NOX activity. In light of these data, toxicity of acetaminophen is discussed., (Copyright © 2011 Elsevier Ltd. All rights reserved.)