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Pulsed electric field (PEF) was conducted for the extraction of proteins/C-Phycocyanins from Arthrospira platensis. The cyanobacterial suspension was treated with 1 µs long pulses at an electric field strength of 40 kV·cm−1 and a treatment energy of 114 kJ·kgsus−1 and 56 kJ·kgsus−1. For benchmarking, additional biomass was processed by high pressure homogenization. Homogeneity of the suspension prior to PEF-treatment influenced the protein/C-phycocyanin extraction efficiency. Stability of C-Phycocyanin during post-PEF incubation time was affected by incubation temperature and pH of the external medium. Biomass concentration severely affect proteins/C-Phycocyanins extraction yield via PEF-treatment. The optimum conditions for extraction of proteins/C-Phycocyanin was obtained at 23 °C while incubating in pH 8-buffer. The energy demand for PEF-treatment amounts to 0.56 MJ·kgdw−1 when processing biomass at 100 gdw·kgsus−1. PEF treatment enhances the protein/C-Phycocyanin extraction yield, thus, it can be suggested as preferential downstream processing method for the production of C-Phycocyanin from A. platensis biomass.

One of the major global challenges of the 21st century is the sustainable supply of the growing world population with food, raw materials and energy. Microalgae cultivated outside farmland under photoautotrophic conditions are a suitable source of renewable raw biomass. By adequate processing of microalgae biomass, products with unique properties can be used as food and feed supplements, in cosmetics and agriculture. The best known examples are dyes astaxanthin, phycocyanin and ß-carotene as well as polyunsaturated fatty acids (PUFA). In spite of this appeal the worldwide production of dry microalgae biomass is only few thousand tonnes per year. This is due to the high investment costs in photo-bioreactors (PBR) and the high energy consumption during down-stream processing of microalgae biomass. To reduce these costs, new technologies and processing methods are required. A suitable alternative to mechanical disruption approaches is the pulsed electric field (PEF) treatment. The extraction efficiency is lower compared to mechanical disruption methods, but the biomass separability is maintained since the morphology of the cells barely changes. In this study we evaluated the potential of PEF treatment for protein and phycocyanin recovery from Chlorella vulgaris and Arthrospira platensis respectively. It is assumed that irreversible electroporation of the cell membrane and the subsequent increased permeabilization are the main effects which allows proteins and other ingredients to pass through the membrane. We observed in our study that efficient protein extraction after PEF treatment requires an incubation step and the progress and kinetics of this outflow is dependent on the biomass concentration and the incubation temperature. The impairment of the molecular outflow at higher temperature (50 °C) and at higher biomass concentration are hints for two different effects. Beside diffusion in a chemical gradient a second biological, enzyme-regulated process within the PEF-treated biomass that facilitates release of proteins from the cells, was considered. This presentation will give an overview about the various factors, such as the post PEF treatment incubation parameters, which have an impact on protein release, as it could be possible to optimize the incubation in order to obtain higher yields.

We have previously reported that the CBD1 peptide (SLEQIWNNMTWMQWDK), corresponding to the consensus caveolin-1 binding domain in human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp41, elicits peptide-specific antibodies. Here, we have investigated the cellular immune response and the protective efficacy against a simian/human immunodeficiency virus (SHIV(162P3)) challenge. In addition to the CBD1 peptide, peptides overlapping the caveolin-binding-motif (CBM) ((622)IWNNMTWMQW(631) or (622)IWNNMTW(628)) were fused to a Gag-p24 T helper epitope for vaccination. All immunized cynomolgus macaques responded to a cocktail peptide immunization by inducing specific T cells and the production of high-titer CBD1/CBM peptide-specific antibodies. Six months after the fourth vaccine boost, six control and five vaccinated animals were challenged weekly by repeated exposure to SHIV(162P3) via the mucosal rectal route. All control animals were infected after 1 to 3 challenges with SHIV, while among the five vaccinated monkeys, three became infected after a delay compared to control; one was infected after the eighth viral challenge, and one remained uninfected even after the ninth SHIV challenge. Immunized animals maintained a CD4 T cell count, and their central memory CD4 T cells were less depleted than in the control group. Furthermore, SHIV challenge stimulates antigen-specific memory T cell response in vaccinated macaques. Our results indicate that peptides derived from the CBM region can be immunogenic and provide protection against SHIV infection in cynomolgus monkeys. IMPORTANCE In HIV-1-producing cells, gp41 exists in a complexed form with caveolin-1, an interaction most probably mediated by the caveolin-1 binding motif. This sequence is highly conserved in every single HIV-1 isolate, thus suggesting that there is constant selective pressure to preserve this sequence for a specific function in the HIV infectious cycle. Consequently, the CBM sequence may represent the “Achilles' heel” of HIV-1 in the development of an efficient vaccine. Our results demonstrate that macaques immunized with the CBM-based peptides displayed a delay in the onset of viral infection and CD4 depletion, as well as a significant induction of antigen-specific memory T cell response, which is essential for the control of HIV/SIV infections. Finally, as HIV-infected individuals lack anti-CBM immune responses, CBM-based vaccines could have applications as a therapeutic vaccine in AIDS patients.

The effectiveness of Motivational Interviewing (MI) to change health behaviors is well documented. Previous studies support use of MI to change oral health behaviors in the areas of early childhood caries and periodontal diseases, but research is limited due to the sparse number of oral health care providers with training in MI. The University of Missouri-Kansas City (UMKC) formally integrated MI training into its dental hygiene curriculum five years ago. Summative program evaluation of UMKC's MI training shows that it effectively equips graduates with MI skills. The aim of this qualitative study was to use semi-structured interviews with nine program alumni to provide insight into the experiences of MI-trained dental hygienists in clinical practice. All interviews were captured with a digital voice recorder, were transcribed, and were resubmitted to the interviewees for checking. Five themes emerged from the data analysis: salience, best practices, barriers, facilitators, and lessons learned. These dental hygienists strongly valued and embraced the spirit of MI. They reported feeling strongly that it should be part of all dental hygiene curricula, and they upheld MI as a best practice. The participants approved of their MI instruction as a whole but felt it was difficult and sometimes not viable in practice. They reported that MI training had improved their communication skills and increased treatment acceptance. Time, difficulty, and managing patient resistance were the most often cited barriers, while a supportive climate and creating a routine were the most often cited facilitators.

Objective The purpose of this study was to identify possible relationships between parent/guardian sociodemographics, intention, knowledge, and the oral health status of their child/ward. Intention includes three factors as defined in the Theory of Planned Behavior: attitudes, subjective norms and perceived control, and oral health status was measured by decayed, missing and filled teeth (dmft) scores. Methods A convenience sample of parent/guardian with child/ward with age of three to five (n = 181 dyads) enrolled in a Head Start program in the state of Florida participated. A cross-sectional observational study comprised of two components, parent/guardian questionnaire and an oral health status form for recording dmft scores of participating child/ward was employed. Results Parent/guardian race/ethnicity and years of education were significantly related to dmft of child/ward. The highest rates of severe early childhood caries (ECC) were found in child/ward whose parent/guardian is Hispanic and parent/guardian with less than a high school education. Multivariate regression analysis found that increased education level of parent/guardian was significantly associated with lower dmft in this population. No significant relationship was found between parent/guardian self-reported intention (attitudes, subjective norms and perceived control), knowledge and dmft scores of the child/ward. Conclusion Researchers have called for greater attention to the impact of parental influences in the aetiology of ECC. Results from this study were consistent with current studies where parent/guardian race/ethnicity and educational level served as predictors of oral health status of children. In this study population, parent/guardian intention and knowledge were not shown to significantly impact the oral health status of their child/ward.

Motivational interviewing (MI) is a person-centered, goal-directed method of communication for eliciting and strengthening intrinsic motivation for behavior change. Originally developed in the field of addiction therapy, MI has been increasing applied in the health professions with a growing body of successful outcomes for tobacco cessation and diabetic control, which can significantly impact oral health. MI has shown preliminary value for impacting oral behaviors that reduce early childhood caries, plaque, and gingival inflammation. While the training in and use of MI by oral health providers is emerging, full integration into dental and dental hygiene curricula has yet to be explored. Therefore, the purpose of this project was to evaluate the full implementation of MI in the classroom and clinic of a dental hygiene curriculum.

Follicular T helper (Tfh) cells, a subset of CD4 T lymphocytes, are essential for memory B cell activation, survival, and differentiation and assist B cells in the production of antigen-specific antibodies. Work performed in recent years pointed out the importance of Tfh cells in the context of HIV and SIV infections. The importance of tissue distribution of Tfh is also an important point since their frequency differs between peripheral blood and lymph nodes compared to the spleen, the primary organ for B cell activation, and differentiation. Our recent observations indicated an early and profound loss of splenic Tfh cells. The role of transcriptional activator and repressor factors that control Tfh differentiation is also discussed in the context of HIV/SIV infection. Because Tfh cells are important for B cell differentiation and antibody production, accelerating the Tfh responses early during HIV/SIV infection could be promising as novel immunotherapeutic approach or alternative vaccine strategies. However, because Tfh cells are infected during the HIV/SIV infection and represent a reservoir, this may interfere with HIV vaccine strategy. Thus, Tfh represent the good and bad guys during HIV infection., JE from the Agence Nationale de Recherches sur le Sida et les Hépatites Virales (ANRS) and from The Canadian HIV Cure Enterprise Team Grant HIG-13305 from the Canadian Institutes of Health Research (CIHR) in partnership with CANFAR and IAS. FM is supported by a fellowship from Fondation du CHU de Québec. CB and YF are supported by fellowships from ANRS. JE acknowledges the support of the Canada Research Chair program. RS is supported by FCT—Fundaçao para a Ciência e a Tecnologia/MEC—Ministério da Educaçao e Ciência através de fundos nacionais e quando aplicavel cofinanciado pelo FEDER, no âmbito do Acordo de Parceria PT2020 referente à unidade de investigaçao n°4293. RS is supported by the Fundaçao para a Ciência e a Tecnologia (FCT) (IF/00021/2014), info:eu-repo/semantics/publishedVersion

Pathway-selective insulin resistance where insulin fails to suppress hepatic glucose production but promotes liver fat storage may underlie glucose and lipid abnormalities after menopause. We tested the mechanisms by which estrogen treatment may alter the impact of a high-fat diet (HFD) when given at the time of ovariectomy (OVX) in mice. Female C57BL/6J mice underwent sham operation, OVX, or OVX with estradiol (E2) treatment and were fed an HFD. Hyperinsulinemic-euglycemic clamps were used to assess insulin sensitivity, tracer incorporation into hepatic lipids, and liver triglyceride export. OVX mice had increased adiposity that was prevented with E2 at the time of OVX. E2 treatment increased insulin sensitivity with OVX and HFD. In sham and OVX mice, HFD feeding induced fatty liver, and insulin reduced hepatic apoB100 and liver triglyceride export. E2 treatment reduced liver lipid deposition and prevented the decrease in liver triglyceride export during hyperinsulinemia. In mice lacking the liver estrogen receptor α, E2 after OVX limited adiposity but failed to improve insulin sensitivity, to limit liver lipid deposition, and to prevent insulin suppression of liver triglyceride export. In conclusion, estrogen treatment may reverse aspects of pathway-selective insulin resistance by promoting insulin action on glucose metabolism but limiting hepatic lipid deposition.