Extraction of Valuable Biomolecules from the Microalga Haematococcus pluvialis Assisted by Electrotechnologies.

The freshwater microalga Haematococcus pluvialis is well known as the cell factory for natural astaxanthin, which composes up to 4-7% of its total dry weight. The bioaccumulation of astaxanthin in H. pluvialis cysts seems to be a very complex process that depends on different stress conditions during its cultivation. The red cysts of H. pluvialis develop thick and rigid cell walls under stress growing conditions. Thus, the biomolecule extraction requires general cell disruption technologies to reach a high recovery rate. This short review provides an analysis of the different steps in H. pluvialis's up and downstream processing including cultivation and harvesting of biomass, cell disruption, extraction and purification techniques. Useful information on the structure of H. pluvialis's cells, biomolecular composition and properties and the bioactivity of astaxanthin is collected. Special emphasis is given to the recent progress in application of different electrotechnologies during the growth stages and for assistance of the recovery of different biomolecules from H. pluvialis.

Post-Chernobyl incidence of papillary thyroid cancer among Belgian children less than 15 years of age in April 1986: a 30-year surgical experience.

OBJECTIVE: We raised the question of a possible relationship in Belgium between the occurrence of papillary thyroid carcinoma (PTC) and age of children (<15 years) at the time of the Chernobyl nuclear plant accident in April 1986. SETTING: Referral university centre for endocrine surgery. MATERIAL AND METHODS: Thirty-year prospective study of the experience of a surgical team with PTC since the Chernobyl accident, taken out of 2349 patients operated on for any thyroid lesions from April 1986 to April 2015, comparing the incidence of PTC by age groups. MAIN OUTCOME MEASUREMENT: Comparison of PTC incidence in patients >15 years (group A) and children <15 years (group B) in April 1986. RESULTS: Out of a total of 2349 patients having undergone thyroid surgery for all types of lesions during 30 year after Chernobyl and born before April 1986, 2164 were >15 years of age at the time of the nuclear accident (group A) and 175 developed PTC (8.1%) compared to 36 PTC (19.5%) that occurred in 185 children <15 years of age (group B) in April 1986 (p < 0.001). CONCLUSIONS: Radiation exposure affected residents of countries (including Belgium) well beyond Ukraine and Belarus. This was demonstrated by a 1990 meteorological report. Over 30 years, there has been a persistent higher incidence of PTC among Belgian children below the age of 15 years at the time of the Chernobyl accident. This relationship with age has even been strengthened by the implementation of more sophisticated immunohistochemical biomarkers diagnostic technology since April 2011.

Technological Advances and Market Developments of Solid-State Batteries: A Review.

Batteries are essential in modern society as they can power a wide range of devices, from small household appliances to large-scale energy storage systems. Safety concerns with traditional lithium-ion batteries prompted the emergence of new battery technologies, among them solid-state batteries (SSBs), offering enhanced safety, energy density, and lifespan. This paper reviews current state-of-the-art SSB electrolyte and electrode materials, as well as global SSB market trends and key industry players. Solid-state electrolytes used in SSBs include inorganic solid electrolytes, organic solid polymer electrolytes, and solid composite electrolytes. Inorganic options like lithium aluminum titanium phosphate excel in ionic conductivity and thermal stability but exhibit mechanical fragility. Organic alternatives such as polyethylene oxide and polyvinylidene fluoride offer flexibility but possess lower ionic conductivity. Solid composite electrolytes combine the advantages of inorganic and organic materials, enhancing mechanical strength and ionic conductivity. While significant advances have been made for composite electrolytes, challenges remain for synthesis intricacies and material stability. Nuanced selection of these electrolytes is crucial for advancing resilient and high-performance SSBs. Furthermore, while global SSB production capacity is currently below 2 GWh, it is projected to grow with a >118% compound annual growth rate by 2035, when the potential SSB market size will likely exceed 42 billion euros.

Budget-Friendly Generation, Biochemical Analyses, and Lentiviral Transduction of Patient-Derived Colon Organoids.

For the past decade, three-dimensional (3D) culture models have been emerging as powerful tools in translational research to overcome the limitations of two-dimensional cell culture models. Thanks to their ability to recapitulate the phenotypic and molecular heterogeneity found in numerous organs, organoids have been used to model a broad range of tumors, such as colorectal cancer. Several approaches to generate organoids exist, with protocols using either pluripotent stem cells, embryonic stem cells, or organ-restricted adult stem cells found in primary tissues, such as surgical resections as starting material. The latter, so-called patient-derived organoids (PDOs), have shown their robustness in predicting patient drug responses compared to other models. Because of their origin, PDOs are natural offspring of the patient tumor or healthy surrounding tissue, and therefore, have been increasingly used to develop targeted drugs and personalized therapies. Here, we present a new protocol to generate patient-derived colon organoids (PDCOs) from tumor and healthy tissue biopsies. We emphasize budget-friendly and reproducible techniques, which are often limiting factors in this line of research that restrict the development of this 3D-culture model to a small number of laboratories worldwide. Accordingly, we describe efficient and cost-effective techniques to achieve immunoblot and high-resolution microscopy on PDCOs. Finally, a novel strategy of lentiviral transduction of PDCOs, which could be applied to all organoid models, is detailed in this article. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: Establishment of PDCOs from biopsies Basic Protocol 2: Long-term maintenance and expansion of PDCOs in BME domes Basic Protocol 3: Cryopreservation and thawing of PDCOs Basic Protocol 4: Lentiviral transduction of PDCOs Basic Protocol 5: Immunoblot and evaluation of variability between donors Basic Protocol 6: Immunofluorescence labeling and high-resolution microscopy of PDCOs Basic Protocol 7: Transcriptomic analyses of PDCOs by RT-qPCR.

A predictive model of organic acids separation by chromatography with strong anionic resins in sulfate form.

Organic acids commonly have quite symmetrical chromatography profiles at low pH (< 1.5) with strong anionic resins, but a significant tailing can be observed with succinic and citric acids. Classical adsorption models, like the Langmuir model, fail to predict this behavior, which can have a major influence on mean retention times and profile shapes, therefore on chromatography performances. A new retention model was developed to better predict organic acid separation with strong anionic resin. This model combines a refined Langmuir adsorption model and an ion-exchange model. Organic acid adsorption is assumed to be due to hydrogen bonding with sulfate and hydrogen sulfate counter-anions on the resin. The adsorption capacity depends mostly on molecular size: up to sixteen formic acid molecules could be adsorbed per counter-anions, meanwhile only two succinic acid or one citric acid molecules could be adsorbed. This adsorption model was then embedded in a generic and accurate modeling approach (continuous column with mass balance equations solved by the conservation element/solution element (CE/SE) method). All parameters of this column model were identified by fitting the simulation to experimental results (equilibrium curves and pulse tests). Then, the column model was validated with original experimental results from a binary mixture pulse test (formic and succinic acids). Results show that simulations are much more predictive for multi-component pulse tests, both in terms of profile shape and retention time, which cannot be captured without considering ion-exchange.

Evaluation of Gas-to-Liquid Transfer with Ceramic Membrane Sparger for H2 and CO2 Fermentation.

Hydrogen and carbon dioxide fermentation to methane, called bio-methanation, is a promising way to provide renewable and easy-to-store energy. The main challenge of bio-methanation is the low gas-to-liquid transfer of hydrogen. Gas injection through a porous membrane can be used to obtain microbubbles and high gas-to-liquid transfer. However, the understanding of bubble formation using a membrane in the fermentation broth is still missing. This study focused on the impact of liquid pressure and flow rate in the membrane, gas flow rate, membrane hydrophobicity, surface, and pore size on the overall gas-to-liquid mass transfer coefficient (KLa) for hydrogen with gas injection through a porous membrane in real fermentation conditions. It has been shown that KLa increased by 13% with an increase in liquid pressure from 0.5 bar to 1.5 bar. The use of a hydrophilic membrane increased the KLa by 17% compared to the hydrophobic membrane. The membrane with a pore size of 0.1 µm produced a higher KLa value compared to 50 and 300 kDa. The liquid crossflow velocity did not impact the KLa in the studied range.

Role of FlbT in flagellin production in Brucella melitensis.

It was recently demonstrated that the pathogen Brucella melitensis produces a polar sheathed flagellum under the control of the master regulator FtcR. However, the regulatory mechanism controlling the flagellar assembly remains unknown. In this work, we investigate the flagellar hierarchy of B. melitensis as well as the flagellin FliC regulation. We show that a mutation in fliF or flgE (coding for the basal body structure and the hook, respectively) does not affect FliC synthesis, suggesting that production of FliC does not depend on the flagellar assembly. We demonstrate that FlbT is a FliC activator since inactivation of flbT causes a decrease in fliC expression by using a fliC-lacZ translational reporter construct. Moreover, the quantitative real-time PCR and Western blot analysis show a marked decrease in fliC mRNA and FliC protein level, respectively. Conversely, the B. melitensis wild-type strain overexpressing flaF fails to produce FliC, suggesting an opposite function. Interestingly, the expression of the flbT gene in an ftcR or an flbT mutant restores FliC production, demonstrating that FlbT plays a regulatory checkpoint role in FliC synthesis. This mechanism could be conserved in the Rhizobiales since complementation of an flbT or an ftcR mutant with flbT from Sinorhizobium meliloti restores FliC synthesis.

RpoE1, an extracytoplasmic function sigma factor, is a repressor of the flagellar system in Brucella melitensis.

The genome of Brucella melitensis contains genes coding for the sigma factors RpoD, RpoN, RpoH1, RpoH2, RpoE1 and RpoE2. Previously published data show that B. melitensis is flagellated and that an rpoE1 mutant overexpresses the flagellar protein FlgE. In this study, we demonstrate that mutation of rpoE1 causes an overexpression of the flagellar genes fliF, flgE, fliC, flaF and flbT, correlating with the production of a longer filament and thereby demonstrating that RpoE1 acts as a flagellar repressor. Moreover, mutation of rpoE1 increases the promoter activity of the flagellar master regulator ftcR, suggesting that RpoE1 acts upstream of ftcR. Together, these data show that RpoE1 represses the flagellar synthesis and filament length in B. melitensis.

CO2 Absorption Using Hollow Fiber Membrane Contactors: Introducing pH Swing Absorption (pHSA) to Overcome Purity Limitation.

Recently, membrane contactors have gained more popularity in the field of CO2 removal; however, achieving high purity and competitive recovery for poor soluble gas (H2, N2, or CH4) remains elusive. Hence, a novel process for CO2 removal from a mixture of gases using hollow fiber membrane contactors is investigated theoretically and experimentally. A theoretical model is constructed to show that the dissolved residual CO2 hinders the capacity of the absorbent when it is regenerated. This model, backed up by experimental investigation, proves that achieving a purity > 99% without consuming excessive chemicals or energy remains challenging in a closed-loop system. As a solution, a novel strategy is proposed: the pH Swing Absorption which consists of manipulating the acido-basic equilibrium of CO2 in the absorption and desorption stages by injecting moderate acid and base amount. It aims at decreasing CO2 residual content in the regenerated absorbent, by converting CO2 into its ionic counterparts (HCO3- or CO32-) before absorption and improving CO2 degassing before desorption. Therefore, this strategy unlocks the theoretical limitation due to equilibrium with CO2 residual content in the absorbent and increases considerably the maximum achievable purity. Results also show the dependency of the performance on operating conditions such as total gas pressure and liquid flowrate. For N2/CO2 mixture, this process achieved a nitrogen purity of 99.97% with a N2 recovery rate of 94.13%. Similarly, for H2/CO2 mixture, a maximum H2 purity of 99.96% and recovery rate of 93.96% was obtained using this process. Moreover, the proposed patented process could potentially reduce energy or chemicals consumption.

In-situ biogas upgrading by bio-methanation with an innovative membrane bioreactor combining sludge filtration and H2 injection.

A bioreactor using membrane technologies was used to demonstrate the feasibility of in-situ bio-methanation coupled to industrial wastewater treatment for biogas upgrading. High biogas productivity (1.7 Nm3Biogas/m3Bioreactor/day) with high CH4 content (97.9%) was reached. In-situ bio-methanation did not affect the COD removal efficiency of anerobic digestion (>94%). Process resilience has been tested for both substrate overload and H2 intermittence injection. Recovery of high CH4 content after 7 days without H2 injection occurred within few hours. Influence of microbial community has been studied showing that both hydrogenotrophic and homoacetogenic-acetoclastic pathways were involved.

Global analysis of quorum sensing targets in the intracellular pathogen Brucella melitensis 16 M.

Many pathogenic bacteria use a regulatory process termed quorum sensing (QS) to produce and detect small diffusible molecules to synchronize gene expression within a population. In Gram-negative bacteria, the detection of, and response to, these molecules depends on transcriptional regulators belonging to the LuxR family. Such a system has been discovered in the intracellular pathogen Brucella melitensis, a Gram-negative bacterium responsible for brucellosis, a worldwide zoonosis that remains a serious public health concern in countries were the disease is endemic. Genes encoding two LuxR-type regulators, VjbR and BabR, have been identified in the genome of B. melitensis 16 M. A DeltavjbR mutant is highly attenuated in all experimental models of infection tested, suggesting a crucial role for QS in the virulence of Brucella. At present, no function has been attributed to BabR. The experiments described in this report indicate that 5% of the genes in the B. melitensis 16 M genome are regulated by VjbR and/or BabR, suggesting that QS is a global regulatory system in this bacterium. The overlap between BabR and VjbR targets suggest a cross-talk between these two regulators. Our results also demonstrate that VjbR and BabR regulate many genes and/or proteins involved in stress response, metabolism, and virulence, including those potentially involved in the adaptation of Brucella to the oxidative, pH, and nutritional stresses encountered within the host. These findings highlight the involvement of QS as a major regulatory system in Brucella and lead us to suggest that this regulatory system could participate in the spatial and sequential adaptation of Brucella strains to the host environment.

Current and novel approaches to downstream processing of microalgae: A review.

Biotechnological application of microalgae cultures at large scale has significant potential in the various fields of biofuels, food and feed, cosmetic, pharmaceutic, environmental remediation and water treatment. Despite this great potential application, industrialisation of microalgae culture and valorisation is still faced with serious remaining challenges in culture scale-up, harvesting and extraction of target molecules. This review presents a general summary of current techniques for harvesting and extraction of biomolecules from microalgae, their relative merits and potential for industrial application. The cell wall composition and its impact on microalgae cell disruption is discussed. Additionally, more recent progress and promising experimental methods and studies are summarised that would allow the reader to further investigate the state of the art. A final survey of energetic assessments of the different techniques is also made. Bead milling and high-pressure homogenisation seem to give clear advantages in terms of target high value compounds extraction from microalgae, with enzyme hydrolysis as a promising emerging technique. Future industrialisation of microalgae for high scale biotechnological processing will require the establishment of universal comparison-standards that would enable easy assessment of one technique against another.

Optimize, Modulate, and Scale-up Resveratrol and Resveratrol Dimers Bioproduction in Vitis labrusca L. Cell Suspension from Flasks to 20 L Bioreactor.

Resveratrol and its oligomers are biologically active compounds. This work brings new insights for the bioproduction of trans-resveratrol with three dimers, pallidol, trans-ε-viniferin, and trans-δ-viniferin, in cell suspension of Vitis labrusca. Conditions of elicitation by methyl jasmonate were optimized for the production of stilbenes using statistical design of experiment. Bio-production of stilbenes was scaled-up to 5 L and in these conditions, trans-resveratrol concentrations reached 237 mg/L, and for pallidol 114 mg/L. The comparison of different elicitation modes (different elicitors, combination with cyclodextrins or adsorbent resin) allowed to reach particularly high concentrations of target molecules: Resveratrol 6.14 g/L, pallidol 0.90 g/L, δ-viniferin 0.54 g/L, and ε-viniferin 0.50 g/L. Scale-up to 20 L-stirring-bioreactor gave similar growth rates to those observed in shake flask culture, with a high production of resveratrol (4.23 g/L) and δ-viniferin (0.76 g/L). This work provides new strategies for the production of stilbenes in plant cell suspension for biological and commercial evaluation.

Colitis Alters Oxysterol Metabolism and is Affected by 4ß-Hydroxycholesterol Administration.

BACKGROUND AND AIMS: Inflammatory bowel diseases [IBD] represent a challenging health issue with a complex aetiology involving genetic and environmental parameters. Although our understanding of the pathophysiology of IBD has improved, much remains to be explored. In this context, bioactive lipids, more specifically oxysterols, i.e. oxygenated derivatives of cholesterol, represent an interesting avenue to investigate. Indeed, oxysterols or their receptors are involved in inflammation and immune regulation. Therefore, we set out to study the oxysterome in IBD. METHODS: We used both high-performance liquid chromatograph/mass spectroscopy and molecular biology tools to quantify oxysterol levels and the expression of their metabolic enzymes in several models of murine colitis [both acute and chronic], as well as in colon biopsies from patients with Crohn's disease and ulcerative colitis. RESULTS: We found that the oxysterome is altered in IBD, in both acute and chronic murine models as well as in human IBD. Two of the oxysterols quantified, 4ß-hydroxycholesterol and 25-hydroxycholesterol, were consistently altered in all our models and therefore could be of interest in this context. Hence, we administered them to mice with colitis. While 25-hydroxycholesterol had no effect, 4ß-hydroxycholesterol worsened colon inflammation. CONCLUSIONS: Our study addresses the potential involvement of oxysterols in colitis and clearly points towards an active role as well as a clinical relevance for these bioactive lipids.

Tacrolimus monotherapy in liver transplantation: one-year results of a prospective, randomized, double-blind, placebo-controlled study.

BACKGROUND: Minimal immunosuppression (IS) is desirable in organ transplantation to reduce side effects and to promote the process of tolerance induction. MATERIAL AND METHODS: Between February 2000 and September 2004, 156 adults (>15 years old) receiving a primary liver graft were enrolled in a prospective, randomized, double-blind, placebo-controlled, investigator-driven single-center study comparing tacrolimus (TAC)-placebo (PL) and TAC-low-dose, short-term (64 days) steroid (ST) IS. There were no exclusion criteria at moment of randomization. All patients had a 12-month follow-up (range, 12-84). RESULTS: Three- and 12-month patient survival rates were 93.6% and 87.2% in the TAC-PL group and 98.7% and 94.7% in TAC-ST group (P = 0.096 and P = 0.093, respectively). Three- and 12-month graft survival rates were 92.3% and 85.9% versus 97.4% and 92.3% (P = 0.14 and 0.13, respectively). By 3 and 12 months, rejection treatment had been given in 20.5% (16 pts) and 23% (18 pts) of TAC-PL patients and in 12.7% (10 pts) and 20.5% (16 pts) of TAC-ST patients (P = 0.20 and 0.54). Corticosteroid-resistant rejection (CRR) at 3 and 12 months was recorded in 12.8% (10 pts) of TAC-PL patients and 3.8% (3 pts) of TAC-ST patients (P = 0.04). When considering the 145 patients transplanted without artificial organ support (n = 145), CRR at 3 and 12 months was recorded in 8.8% (6/68 pts) of TAC-PL patients and in 3.9% (3/77 pts) of TAC-ST patients (P = 0.22). Vanishing bile duct syndrome was diagnosed in 1 (1.2%) TAC-PL patient and 4 (5.1%) TAC-ST patients (P = 0.17). By 1 year, 78.2% (61/78) of TAC-PL patients and 82% (64/78) of TAC-ST patients were on TAC monotherapy (P = 0.54). When considering 67 TAC-PL and 74 TAC-ST survivors, rates of monotherapy were 91% (61 pts) and 86.5% (64 pts) (P = 0.39). At 1 year, 62.5% (42 pts) of TAC-PL survivors and 64.9% (48 pts) of TAC-ST survivors were on low-dosage (<6 ng/mL) TAC monotherapy (P 0.79). CONCLUSION: TAC monotherapy can be achieved safely without compromising graft nor patient survival in a primary, even unselected, adult liver transplant population. The higher incidence of early CRR in the TAC-PL group related to the significantly higher number of patients transplanted while being on artificial organ support. In such condition, this monodrug immunosuppressive strategy needs to be adapted. TAC monotherapy strategy should lay the basis for further large scale minimization studies in liver transplantation.

Refractory thyroid carcinoma: which systemic treatment to use?

The incidence of thyroid cancer has increased markedly in recent decades, but has been stable in terms of mortality rates. For the most part, these cancers are treated with surgery, which may or may not be followed by radioactive iodine depending on the tumor subtype. Still, many of these cancers will recur and may be treated with radioactive iodine or another surgery. It is unclear what treatment is best for cases of locally advanced or metastatic thyroid cancer that are refractory to radioactive iodine. Chemotherapy has a very low response rate. However, in the past few years, several systemic therapies, primarily targeted, have emerged to improve the overall survival of these patients. Alternative treatments are also of interest, namely peptide receptor radionuclide therapy or immunotherapy.

Management of a jejunal obstruction caused by the migration of a laparoscopic adjustable gastric banding. A case report.

INTRODUCTION: We present a rare case of jejunal obstruction due to the migration of a laparoscopic adjustable gastric band (LAGB) that occurred 10 years after surgery and was successfully treated by laparoscopy. This report is compliant with the SCARE guidelines. PRESENTATION OF CASE: A 42-year-old woman who underwent LAGB for morbid obesity 10 years ago was admitted with a small bowel obstruction due to the migration of a LAGB in the proximal small bowel. An attempt to endoscopic removal was unsuccessful and resulted in a laparoscopic extraction of the band. The post-operative course was uneventful. DISCUSSION: Formerly, LAGB was considered the safest technique in bariatric surgery. However, the rate of complication increases in long-term studies. When the IGM of the band is diagnosed, removal is the only issue. Small bowel obstruction caused by a migrated band appears to be a rare complication following IGM, and the only therapeutic option is surgery because an endoscopic procedure is not reliable. Furthermore, LAGB appears to be a less effective technique for weight loss than the sleeve gastrectomy and the gastric bypass. CONCLUSION: Small bowel obstruction caused by LAGB migration is a rare but serious complication following IGM. In such cases, endoscopy has to be avoided because of the risk of jejunal disruption. The only way to treat it properly is surgery. This type of late complication reinforces the interest in the techniques currently used in bariatric surgery such as sleeve gastrectomy and gastric bypass, providing also a better weight loss than the LAGB.

Purification of organic acids by chromatography with strong anionic resins: Investigation of uptake mechanisms.

Bio-based organic acids are promising renewable carbon sources for the chemical industry. However energy-consuming purification processes are used, like distillation or crystallization, to reach high purities required in some applications. That is why preparative chromatography was studied as an alternative separation technique. In a previous work dealing with the purification of lactic, succinic and citric acids, the Langmuir model was insufficient to explain the elution profiles obtained with a strong anionic resin. Consequently the Langmuir model was coupled with a usual ion-exchange model to take into account the retention of their conjugate bases (<2%), which are commonly neglected at low pH (<1.5). Elution simulations with both uptake mechanisms fitted very well with experimental pulse tests. Only two parameters were optimized (equilibrium constant of acid uptake and ion-exchange selectivity coefficient of conjugate base) and their value were coherent with experimental and resin suppliers' data. These results confirmed that the singular tailing and apparent delay observed with succinic and citric acids can be explained by the high affinity of succinate and citrate for resin cationic sites. The model was implemented in a preparative chromatography simulation program in order to optimize operating parameters of our pilot-scale ISMB unit (Improved Simulated Moving Bed). The comparison with experimental ISMB profiles was conclusive.