Dectin-2 is critical for phagocyte function and resistance to Paracoccidioides brasiliensis in mice.

Germline-encoded pattern recognition receptors, particularly C-type lectin receptors (CLRs), are essential for phagocytes to sense invading fungal cells. Among CLRs, Dectin-2 (encoded by Clec4n) plays a critical role in the antifungal immune response as it recognizes high-mannose polysaccharides on the fungal cell wall, triggering phagocyte functional activities and ultimately determining adaptive responses. Here, we assessed the role of Dectin-2 on the course of primary Paracoccidioides brasiliensis systemic infection in mice with Dectin-2-targeted deletion. Paracoccidioides brasiliensis constitutes the principal etiologic agent of paracoccidioidomycosis, the most prominent invasive mycosis in Latin American countries. The deficiency of Dectin-2 resulted in shortened survival rates, high lung fungal burden, and increased lung pathology in mice infected with P. brasiliensis. Consistently, dendritic cells (DCs) from mice lacking Dectin-2 infected ex vivo with P. brasiliensis showed impaired secretion of several proinflammatory and regulatory cytokines, including TNF-α, IL-1ß, IL-6, and IL-10. Additionally, when cocultured with splenic lymphocytes, DCs were less efficient in promoting a type 1 cytokine pattern secretion (i.e., IFN-γ). In macrophages, Dectin-2-mediated signaling was required to ensure phagocytosis and fungicidal activity associated with nitric oxide production. Overall, Dectin-2-mediated signaling is critical to promote host protection against P. brasiliensis infection, and its exploitation might lead to the development of new vaccines and immunotherapeutic approaches.

We report a critical role of the innate immune receptor Dectin-2 during Paracoccidioides brasiliensis infection. Fungal sensing by Dectin-2 improved the survival of mice and lowered fungal burden. Further, Dectin-2 was required for cytokine production, phagocytosis, and fungal killing by phagocytes.

Generation and persistence of S1 IgG and neutralizing antibodies in post-COVID-19 patients.

BACKGROUND: Antibody-mediated immune response plays an important role in protection against reinfection. In the case of SARS-CoV-2 infection, the maximum duration of antibody response is still unknown. In this work, the generation of neutralizing  antibodies (NAbs) and IgG antibodies against the S1 subunit (S1 IgG ) of SARS-CoV-2 and their possible duration were determined through decay models. METHODS: 132 participants with SARS-CoV-2 infection were classified according to the severity of the disease. Seroconversion and persistence of S1 IgG antibodies and NAbs were determined by ELISA, samples were taken at two different times post-infection and duration of those antibodies was estimated using Linear Mixed Models (LMMs). RESULTS: The highest amount of S1 IgGs antibodies was associated with age (41 years or older), greater severity of COVID-19 and male gender. NAbs production was associated with the same variables, except for age. The percentage of NAbs decay is higher in the asymptomatic group (P = 0.033), while in S1 IgG antibodies decay, no statistical difference was found between the 4 severity groups. An exponential decay model was built by using a LMM and similarly, two dispersion regions where constructed. The duration of S1 IgG antibodies was 744 days (668-781) for first region and 744 days (453-1231) for the second. Regarding NAbs, an adaptative LMM was used to model a logistic function, determining a duration of 267 days (215-347). CONCLUSION: Humoral immunity to SARS-CoV-2 infection depends on the severity of the disease, gender and age. This immune response could be long-lasting as for other coronaviruses.

Effectiveness of a lifestyle weight-loss intervention targeting inactive former elite athletes: the Champ4Life randomised controlled trial.

OBJECTIVES: Many athletes struggle in managing the end of their career, often gaining weight and adopting unhealthy lifestyles. Lifestyle programmes targeting former athletes who have gained substantial fat mass (FM) postsports career are lacking. We studied the effects of the Champ4Life programme on body composition and other health-related outcomes in former elite athletes with overweight or obesity. METHODS: Ninety-four former athletes(42.4±7.3 y, 34.0% female) were recruited and randomly assigned to either an intervention group (IG; n=49) or a control group (CG; n=45). The IG attended 12 educational sessions addressing physical activity, weight management and nutrition. They also had a nutrition appointment aimed to prescribe a moderate caloric deficit(~300-500 kcal/day). Dual-energy X-ray absorptiometry was used to assess body composition. The Short-Form Health Survey-36 questionnaire was used to measure general health-related quality of life. Blood samples were collected to assess cardiometabolic health parameters. RESULTS: At 12 months, the IG lost more weight (estimated difference (ED)=-5.3 kg; -6.9 to -3.8), total FM (ED=-4.1 kg; -5.4 to -2.8) and abdominal FM (ED=-0.49 kg; -0.64 to -0.33) than did the CG (p's<0.001). Cardiometabolic health markers also improved significantly (p<0.05) more in the IG at 12 months (insulin (ED=-4.9 µU/mL;-8.0 to -1.8); homoeostatic model assessment (ED=-1.2; -2.1 to -0.4); total cholesterol (ED=-21.8 mg/dL; -35.4 to -8.2); low-density lipoprotein (ED=18.2 mg/dL;-29.2 to -7.1)), as did quality-of-life dimensions (physical functioning (ED=11.7; 6.5 to 16.9); physical role (ED=17.6; 2.1 to 33.0); general health (ED=19.4; 11.4 to 27.4); vitality (ED=13.3; 5.3 to 21.3) and mental health (ED=12.3; 4.1 to 20.6)). CONCLUSIONS: The Champ4Life programme was effective in substantially reducing total and abdominal FM while preserving fat-free mass and improving health-related markers. These findings will enable evidence-based decisions when implementing lifestyle interventions targeting retired elite athletes. TRIAL REGISTERATION NUMBER: NCT03031951.

Zymosan enhances in vitro phagocyte function and the immune response of mice infected with Paracoccidioides brasiliensis.

Paracoccidioides brasiliensis is the major etiologic agent of Paracoccidioidomycosis (PCM), the most frequent human deep mycosis in Latin America. It is proposed that masking of ß-glucan in P. brasiliensis cell wall is a critical virulence factor that contributes to the development of a chronic disease characterized by a long period of treatment, which is usually toxic. In this context, the search for immunomodulatory agents for therapeutic purposes is highly desirable. One strategy is to use pattern recognition receptors (PRRs) ligands to stimulate the immune response mediated by phagocytes. Here, we sought to evaluate if Zymosan, a ß-glucan-containing ligand of the PRRs Dectin-1/TLR-2, would enhance phagocyte function and the immune response of mice challenged with P. brasiliensis. Dendritic cells (DCs) infected with P. brasiliensis and treated with Zymosan showed improved secretion of several proinflammatory cytokines and expression of maturation markers. In addition, when cocultured with splenic lymphocytes, these cells induced the production of a potential protective type 1 and 17 cytokine patterns. In macrophages, Zymosan ensued a significant fungicidal activity associated with nitric oxide production and phagolysosome acidification. Importantly, we observed a protective effect of Zymosan-primed DCs delivered intranasally in experimental pulmonary PCM. Overall, our findings support the potential use of ß-glucan-containing compounds such as Zymosan as an alternative or complementary antifungal therapy. LAY SUMMARY: We report for the first time that Paracoccidioides brasiliensis-infected phagocytes treated with Zymosan (cell wall extract from bakers' yeast) show enhanced cytokine production, maturation, and fungal killing. Also, Zymosan-primed phagocytes induce a protective immune response in infected mice.

Increased risk of depression and impairment in quality of life in patients with lamellar ichthyosis.

Lamellar ichthyosis (LI) is a genetic skin disorder characterized by dark brown scales, palmoplantar hyperkeratosis, pain, and itching. LI severity could have implications in psychological aspects, causing depression and impairment in the quality of life (QoL) of patients. In this study, we used the Congenital Ichthyosis Severity Index, the Depression Beck Inventory-II (DBI-II), and the Dermatologic Life Quality Index (DLQI) to assess severity, level of depression, and impairment in QoL in a group of patients with LI. We observed that the majority of the patients presented a high severity level concerning the presence of scales (57.7%), while for erythema and alopecia, the severity was less 80% of the analyzed patients presented depression, while only 20.8% of individuals of the control group presented it (P < .001, OR = 15.2). While for QoL, only 4.3% of the patients did not exhibit any impairment. Finally, the increase in the score obtained in DBI-II was correlated with the DLQI score (rs = 0.663, P = .0014). Our results suggest that patients with LI have an increased risk of suffering depression and impairment in their QoL; thus, the management of their disease should be performed from a multidisciplinary perspective to improve the global aspects of their lives.

Methods and cell-based strategies to produce antibody libraries: current state.

Antibodies are critical components of the adaptive immune system, whose therapeutic applications have been growing exponentially in the last years. Discovery and development of therapeutic antibodies encompasses in vivo immunization, synthetic libraries, and surface display methodologies. To overcome some of their limitations, several platforms in higher eukaryotic cells have been developed. Moreover, these platforms aim to replicate in the bench both primary and secondary antibody diversification mechanisms that occur in vivo. Here, we describe the latest strategies that have been used to mirror both naïve and affinity-maturated antibody repertoire. KEY POINTS: • Therapeutic antibodies are one of the most promising classes of drugs to fight diseases. • Antibodies discovered through hybridoma or display technologies require further engineering. • Innovative antibody discovery platforms in higher eukaryotic cells have been developed.

Inhibition of HIV replication through siRNA carried by CXCR4-targeted chimeric nanobody.

Small interfering RNA (siRNA) application in therapy still faces a major challenge with the lack of an efficient and specific delivery system. Current vehicles are often responsible for poor efficacy, safety concerns, and burden costs of siRNA-based therapeutics. Here, we describe a novel strategy for targeted delivery of siRNA molecules to inhibit human immunodeficiency virus (HIV) infection. Specific membrane translocation of siRNA inhibitor was addressed by an engineered nanobody targeting the HIV co-receptor CXCR4 (NbCXCR4) in fusion with a single-chain variable fragment (4M5.3) that carried the FITC-conjugated siRNA. 4M5.3-NbCXCR4 conjugate (4M5.3X4) efficiently targeted CXCR4+ T lymphocytes, specifically translocating siRNA by receptor-mediated endocytosis. Targeted delivery of siRNA directed to the mRNA of HIV transactivator tat silenced Tat-driven viral transcription and inhibited the replication of distinct virus clades. In summary, we have shown that the engineered nanobody chimera developed in this study constitutes an efficient and specific delivery method of siRNAs through CXCR4 receptor.

Integrated in Silico and Experimental Approach towards the Design of a Novel Recombinant Protein Containing an Anti-HER2 scFv.

Biological therapies, such as recombinant proteins, are nowadays amongst the most promising approaches towards precision medicine. One of the most innovative methodologies currently available aimed at improving the production yield of recombinant proteins with minimization of costs relies on the combination of in silico studies to predict and deepen the understanding of the modified proteins with an experimental approach. The work described herein aims at the design and production of a biomimetic vector containing the single-chain variable domain fragment (scFv) of an anti-HER2 antibody fragment as a targeting motif fused with HIV gp41. Molecular modeling and docking studies were performed to develop the recombinant protein sequence. Subsequently, the DNA plasmid was produced and HEK-293T cells were transfected to evaluate the designed vector. The obtained results demonstrated that the plasmid construction is robust and can be expressed in the selected cell line. The multidisciplinary integrated in silico and experimental strategy adopted for the construction of a recombinant protein which can be used in HER2+-targeted therapy paves the way towards the production of other therapeutic proteins in a more cost-effective way.

Impact of the First Wave of the COVID-19 Pandemic on Trade between Canada and the United States.

We examine how the coronavirus disease 2019 (COVID-19) pandemic has affected trade between Canada and the United States, using a novel dataset on monthly bilateral trade flows between Canadian provinces and US states merged with COVID-19 health data. Our results show that a one-standard-deviation increase in COVID-19 severity (case levels, hospitalizations, deaths) in a Canadian province leads to a 3.1 percent to 4.9 percent fall in exports and a 6.7 percent to 9.1 percent fall in imports. Decomposing our analysis by industry, we determine that trade in the manufacturing industry was most negatively affected by the pandemic, and the agriculture industry had the least disruption to trade flows. Our descriptive evidence suggests that lockdowns may also have reduced Canadian exports and imports. However, although our regression coefficients are consistent with that finding, they are not statistically significant, perhaps because of the lack of variation as a result of similar timing in the imposition of restrictions across provinces.

Cet article examine l'incidence de la maladie à coronavirus 2019 (COVID-19) sur le commerce entre le Canada et les États-Unis. La recherche utilise un nouvel ensemble de données sur les échanges commerciaux bilatéraux mensuels entre les provinces canadiennes et les États américains croisées avec les données médicales reliées à la COVID-19. Nos résultats démontrent qu'un accroissement d'un seul écart-type de la sévérité de la COVID 19 (nombre de cas, hospitalisations, décès) dans une province canadienne a causé une chute de 3,1 à 4,9 pour cent des exportations et une chute de 6,7 à 9,1 pour cent des importations. En décomposant notre analyse par industrie, nous constatons que le commerce dans l'industrie manufacturière a été le plus touché négativement par la pandémie, et que le secteur agricole a été le moins perturbé quant aux échanges commerciaux. Nos données descriptives montrent que les périodes de confinement peuvent avoir réduit, à leur tour, les importations et exportations canadiennes. Cependant, même si nos coefficients de régression concordent avec ces résultats, ils ne sont pas pour autant significatifs statistiquement, peut-être en raison du manque de variation découlant des restrictions imposées dans toutes les provinces.

Hyaluronic acid in wound dressings.

Human skin possesses an essential function in the maintenance of individuals' health. However, it may undergo a variety of lesions that produce wounds of distinct severity. In this respect, instantly after any skin wound, the process of tissue regeneration and repair initiates. Nevertheless, diverse factors can delay this process, including bacterial infections, nutritional status, age, hypoxia, chronic diseases, necrosis, and vascular and arterial diseases. Thus, wound dressings are frequently used to improve wound healing. Those wound dressings are fabricated with diverse materials, which confer them different properties. In this regard, hyaluronic acid is a natural polysaccharide widely distributed in extracellular matrices of mammal tissues, which possesses remarkable attributes in terms of biocompatibility, biodegradability, and low cost. Moreover, hyaluronic acid exhibits several beneficial effects on wound healing, such as the decrease of inflammatory processes, regulation of tissue remodeling, and enhancement of angiogenesis. Therefore, in recent years, there is growing attention in this polysaccharide for the design and manufacture of novel wound dressings, which have shown encouraging properties. Here, we describe the different approaches of hyaluronic acid for the production of wound dressings, encompassing hydrogels, films, scaffolds, foams, topical formulations, and nanoformulations, as well as its beneficial effects on wound healing. Finally, we discuss perspectives about the use of hyaluronic acid in wound dressings.

Xanthan gum in drug release.

Controlled release is of vital relevance for many drugs; thus, there is a keen interest in materials that can improve the release profiles of formulations administered via buccal, transdermal, ophthalmic, vaginal, and nasal. The desirable effects of those materials include the improvement of stability, adhesiveness, solubility, and retention time. Hence, different synthetic and natural polymers are utilized to achieve these objectives. In this respect, xanthan gum is an anionic polysaccharide that can be obtained from Xanthomonas bacteria. It is a natural polymer broadly employed in numerous food products, lotions, shampoos, and dermatological articles. Furthermore, due to its physicochemical features, xanthan gum is growingly utilized for the development and improvement of drug delivery systems. In this regard, encouraging findings have been revealed by recent formulations for pharmaceutical applications, including antiviral carriers, antibacterial transporters, transdermal patches, vaginal formulations, and anticancer medications. In this article, we perform a concise description of the chemical properties of xanthan gum and its role as a modifier of drug release. Furthermore, we present an outlook of the state of the art of research focused on the utilization of xanthan gum in varied pharmaceutical formulations, which include tablets, films, hydrogels, and nanoformulations. Finally, we discuss some perspectives about the use of xanthan gum in these formulations.

Synthetic antibody discovery against native antigens by CRISPR/Cas9-library generation and endoplasmic reticulum screening.

Despite the significant advances of antibodies as therapeutic agents, there is still much room for improvement concerning the discovery of these macromolecules. Here, we present a new synthetic cell-based strategy that takes advantage of eukaryotic cell biology to produce highly diverse antibody libraries and, simultaneously, link them to a high-throughput selection mechanism, replicating B cell diversification mechanisms. The interference of site-specific recognition by CRISPR/Cas9 with error-prone DNA repair mechanisms was explored for the generation of diversity, in a cell population containing a gene for a light chain antibody fragment. We achieved up to 93% of cells containing a mutated antibody gene after diversification mechanisms, specifically inside one of the antigen-binding sites. This targeted variability strategy was then integrated into an intracellular selection mechanism. By fusing the antibody with a KDEL retention signal, the interaction of antibodies and native membrane antigens occurs inside the endoplasmic reticulum during the process of protein secretion, enabling the detection of high-quality leads for expression and affinity by flow cytometry. We successfully obtained antibody lead candidates against CD3 as proof of concept. In summary, we developed a novel antibody discovery platform against native antigens by endoplasmic synthetic library generation using CRISPR/Cas9, which will contribute to a faster discovery of new biotherapeutic molecules, reducing the time-to-market.

A Step Forward in Breast Cancer Research: From a Natural-Like Experimental Model to a Preliminary Photothermal Approach.

Breast cancer is one of the most frequently diagnosed malignancies and common causes of cancer death in women. Recent studies suggest that environmental exposures to certain chemicals, such as 7,12-Dimethylbenzanthracene (DMBA), a chemical present in tobacco, may increase the risk of developing breast cancer later in life. The first-line treatments for breast cancer (surgery, chemotherapy or a combination of both) are generally invasive and frequently associated with severe side effects and high comorbidity. Consequently, novel approaches are strongly required to find more natural-like experimental models that better reflect the tumors' etiology, physiopathology and response to treatments, as well as to find more targeted, efficient and minimally invasive treatments. This study proposes the development and an in deep biological characterization of an experimental model using DMBA-tumor-induction in Sprague-Dawley female rats. Moreover, a photothermal therapy approach using a near-infrared laser coupled with gold nanoparticles was preliminarily assessed. The gold nanoparticles were functionalized with Epidermal Growth Factor, and their physicochemical properties and in vitro effects were characterized. DMBA proved to be a very good and selective inductor of breast cancer, with 100% incidence and inducing an average of 4.7 tumors per animal. Epigenetic analysis showed that tumors classified with worst prognosis were hypomethylated. The tumor-induced rats were then subjected to a preliminary treatment using functionalized gold nanoparticles and its activation by laser (650-900 nm). The treatment outcomes presented very promising alterations in terms of tumor histology, confirming the presence of necrosis in most of the cases. Although this study revealed encouraging results as a breast cancer therapy, it is important to define tumor eligibility and specific efficiency criteria to further assess its application in breast cancer treatment on other species.

Dental Dam Application for Endodontics in Dogs-A Novel Clamp Kit.

Although rubber dams are widely used in endodontic treatment in humans with well-known advantages, their use in veterinary medicine is uncommon. The use of a dental rubber dam provides better control of cross-infection, prevents soft tissue contact of chemicals, and improves treatment efficiency. The purpose of this article is to describe a new line of clamps specifically designed for dogs and to review the procedure and materials used for isolating the operative field in endodontic patients. This new design of clamps, better adapted to canine tooth anatomy with different sizes and conformations, has been successfully used in dogs by the authors with good clinical results. The clamps allow for better adaptation to the tooth without injuring the gingiva or the furcation and provide increased retention of the dam for more effective isolation. Given the proven benefits in humans, the authors expect that the widespread use of a rubber dam with clamps specifically designed for canine dental anatomy will improve clinical outcomes in endodontics.

Antibacterial activity of Pinus elliottii against anaerobic bacteria present in primary endodontic infections.

Endodontic infections have a polymicrobial nature, but anaerobic bacteria prevail among the infectious microbes. Considering that it is easy to eliminate planktonic bacteria, biofilm-forming bacteria still challenge clinicians during the fight against endodontic diseases. The chemical constituents of the oleoresin of Pinus elliottii, a plant belonging to the family Pinaceae, stand out in the search for biologically active compounds based on natural products with potential application in the treatment of endodontic infections. Indeed, plant oleoresins are an abundant natural source of diterpenes that display significant and well-defined biological activities as well as potential antimicrobial action. In this context, this study aimed to (1) evaluate the in vitro antibacterial activity of the oleoresin, fractions, and subfractions of P. elliottii as well as the action of dehydroabietic acid against 11 anaerobic bacteria that cause endodontic infection in both their planktonic and biofilm forms and (2) assess the in vitro antibiofilm activity of dehydroabietic acid against the same group of bacteria. The broth microdilution technique helped to determine the minimum inhibitory concentration (MIC) of the oleoresin and fractions. This same technique aided determination of the MIC values of nine subfractions of Fraction 1, the most active fraction. The MIC, minimum bactericidal concentration, and antibiofilm activity of dehydroabietic acid against the tested anaerobic bacteria were also examined. The oleoresin and fractions, especially fraction PE1, afforded promising MIC values, which ranged from 0.4 to 50 µg/mL. Concerning the nine evaluated subfractions, PE1.3 and PE1.4 furnished the most noteworthy MIC values, between 6.2 and 100 µg/mL. Dehydroabietic acid displayed antibacterial activity, with MIC values lying from 6.2 to 50 µg/mL, as well as bactericidal effect for all the investigated bacteria, except for Prevotella nigrescens. Assessment of the antibiofilm activity revealed significant results--MICB50 lay between 7.8 and 62.5 µg/mL, and dehydroabietic acid prevented all the evaluated bacteria from forming a biofilm. Hence, the chemical constituents of P. elliottii are promising biomolecules to develop novel therapeutic strategies to fight against endodontic infections.

Effectiveness of photodynamic therapy on treatment response and survival in patients with recurrent oral squamous cell carcinoma: A systematic review.

BACKGROUND: This systematic review assessed the effectiveness of photodynamic therapy (PDT) in patients with recurrent oral squamous cell carcinoma (OSCC). METHODS: Clinical studies on recurrent OSCC treated with PDT alone were included. Combined treatment strategies were excluded. The search was performed on Medline/Pubmed, Cochrane Library, Embase, Web of Science and ClinicalTrials.gov, manual search, and grey literature. RESULTS: The eleven included studies were observational. The risk of bias and methodological quality were evaluated using the Newcastle-Ottawa Quality Assessment Scale. The studies reported the use of hematoporphyrin derivative, PhotofrinⓇ, FoscanⓇ and 5-aminolevulinic acid. Data on treatment response and survival was collected. Secondarily, postoperative courses and patient's quality of life/acceptance were reported whenever available. PhotofrinⓇ and FoscanⓇ were the most used photosensitisers, with more complete responses. Lesions responding less favourably were on posterior regions or deep-seated in the tissue. CONCLUSIONS: Although treatment response differs between treatment protocols, PDT stands as a viable treatment option to be considered, as it can achieve therapeutic results and disease-free, long-lasting periods. Partial treatment responses may be of interest when achieving eligibility for other treatment strategies. Despite this study's limitations, which considered four photosensitisers, PhotofrinⓇ was the most used but more recent photosensitisers like FoscanⓇ have greater chemical stability, tissue penetration, and may be more efficacious on recurrent OSCC.

Antiviral Action against SARS-CoV-2 of a Synthetic Peptide Based on a Novel Defensin Present in the Transcriptome of the Fire Salamander (Salamandra salamandra).

The potential emergence of zoonotic diseases has raised significant concerns, particularly in light of the recent pandemic, emphasizing the urgent need for scientific preparedness. The bioprospection and characterization of new molecules are strategically relevant to the research and development of innovative drugs for viral and bacterial treatment and disease management. Amphibian species possess a diverse array of compounds, including antimicrobial peptides. This study identified the first bioactive peptide from Salamandra salamandra in a transcriptome analysis. The synthetic peptide sequence, which belongs to the defensin family, was characterized through MALDI TOF/TOF mass spectrometry. Molecular docking assays hypothesized the interaction between the identified peptide and the active binding site of the spike WT RBD/hACE2 complex. Although additional studies are required, the preliminary evaluation of the antiviral potential of synthetic SS-I was conducted through an in vitro cell-based SARS-CoV-2 infection assay. Additionally, the cytotoxic and hemolytic effects of the synthesized peptide were assessed. These preliminary findings highlighted the potential of SS-I as a chemical scaffold for drug development against COVID-19, hindering viral infection. The peptide demonstrated hemolytic activity while not exhibiting cytotoxicity at the antiviral concentration.

Bioactives Overproduction through Operational Strategies in the Ichthyotoxic Microalga Heterosigma akashiwo Culture.

The red tide-forming microalga Heterosigma akashiwo has been associated with massive events of fish deaths, both wild and cultured. Culture conditions are responsible for the synthesis or accumulation of some metabolites with different interesting bioactivities. H. akashiwo LC269919 strain was grown in a 10 L bubble column photobioreactor artificially illuminated with multi-coloured LED lights. Growth and production of exopolysaccharides, polyunsaturated fatty acids (PUFAs), and carotenoids were evaluated under different culture modes (batch, fed-batch, semicontinuous, and continuous) at two irradiance levels (300 and 700 µE·s-1·m-2). Continuous mode at the dilution rate of 0.2·day-1 and 700 µE·s-1·m-2 provided the highest production of biomass, PUFAs (132.6 and 2.3 mg·L-1·day-1), and maximum fucoxanthin productivity (0.16 mg·L-1·day-1). The fed-batch mode accumulated exopolysaccharides in a concentration (1.02 g·L-1) 10-fold over the batch mode. An extraction process based on a sequential gradient partition with water and four water-immiscible organic solvents allowed the isolation of bioactive fucoxanthin from methanolic extracts of H. akashiwo. Metabolites present in H. akashiwo, fucoxanthin and polar lipids (i.e., eicosapentaenoic acid (EPA)), or probably such as phytosterol (ß-Sitosterol) from other microalgae, were responsible for the antitumor activity obtained.

Effectiveness of photodynamic therapy on treatment response and survival of patients with recurrent oral squamous cell carcinoma: a systematic review protocol.

OBJECTIVE: This review aims to systematically examine the effectiveness of photodynamic therapy for the treatment of patients with recurrent oral squamous cell carcinoma. INTRODUCTION: Oral squamous cell carcinoma is a significant public health problem, and is the seventh most common cancer. Its incidence is mainly due to tobacco use, alcohol consumption, and HPV infection. The survival rates are poor due to diagnosis at advanced stages, with high recurrence rates. Although current evidence does not point to photodynamic therapy as a first-line option, this treatment might be suitable for treating recurrent stages of the cancer where conventional treatments were ineffective. Despite the potential of photodynamic therapy, there is a need to verify the scientific evidence to support its indication for the treatment of recurrent oral squamous cell carcinoma. INCLUSION CRITERIA: This review will consider studies on any stage of recurrent oral squamous cell carcinoma treated with photodynamic therapy after receiving first-line conventional treatments. Patients of any age, gender, and geographic location will be included. The primary outcomes will be to evaluate response to treatment, focusing on remission, recurrence, change in size of the lesion, alleviation of symptoms, and survival. Secondary outcomes will be postoperative complications, presence of necrosis, patient quality of life after treatment, and patient satisfaction. METHODS: Studies will be searched using a combination of index terms and keywords in MEDLINE, Cochrane Central, Web of Science, Embase, and ClinicalTrials.gov. No date limits will be applied. Articles written in English, French, Spanish, or Portuguese will be considered. Findings will be provided as a narrative synthesis, structured around the photodynamic therapy protocol used. A meta-analysis is planned and subgroup analysis will be conducted if possible. The certainty of findings will be assessed. SYSTEMATIC REVIEW REGISTRATION NUMBER: PROSPERO CRD42020141075.

Isolation and Identification of Cytotoxic Compounds Present in Biomaterial Life®.

Direct pulp capping consists of a procedure in which a material is directly placed over the exposed pulp to maintain dental vitality. Although still widely used in clinical practice, previous in vitro studies found that the biomaterial Life® presented high cytotoxicity, leading to cell death. This study aimed to identify the Life® constituents responsible for its cytotoxic effects on odontoblast-like cells (MDPC-23). Aqueous medium conditioned with Life® was subjected to liquid-liquid extraction with ethyl acetate. After solvent removal, cells were treated with residues isolated from the organic and aqueous fractions. MTT and Trypan blue assays were carried out to evaluate the metabolic activity and cell death. The organic phase residue promoted a significant decrease in metabolic activity and increased cell death. On the contrary, no cytotoxic effects were observed with the mixture from the aqueous fraction. Spectroscopic and spectrometric methods allowed the identification of the toxic compounds. A mixture of the regioisomers ortho, para, and meta of N-ethyl-toluenesulfonamide was identified as the agent responsible for the toxicity of biomaterial Life® in MDPC-23 cells. These findings contribute to improving biomaterial research and development.