Search

Mitochondria are dynamic organelles of endosymbiotic origin that are essential components of eukaryal cells. They contain their own genetic machinery, have multicopy genomes and like their bacterial ancestors they consist of two membranes. However, the majority of the ancestral genome has been lost or transferred to the nuclear genome of the host, preserving only a core set of genes involved in oxidative phosphorylation. Mitochondria perform numerous biological tasks ranging from bioenergetics to production of protein co-factors, including heme and iron-sulfur clusters. Due to the importance of mitochondria in many cellular processes, mitochondrial dysfunction is implicated in a wide variety of human disorders. Much of our current knowledge on mitochondrial function and dysfunction comes from studies using Saccharomyces cerevisiae. This yeast has good fermenting capacity, rendering tolerance to mutations that inactivate oxidative phosphorylation and complete loss of mitochondrial DNA. Here, we review yeast mitochondrial metabolism and function with focus on S. cerevisiae and its contribution in understanding mitochondrial biology. We further review how systems biology studies, including mathematical modeling, has allowed gaining new insight into mitochondrial function, and argue that this approach may enable us to gain a holistic view on how mitochondrial function interacts with different cellular processes. [ABSTRACT FROM AUTHOR]

Background: The aim was to determine prevalence and age at seroconversion of thyroid autoimmunity in relation to islet autoantibodies, gender and HLA-DQ genotypes in children with increased risk for type 1 diabetes followed from birth. Methods: In 10-year-old children (n = 1874), blood samples were analysed for autoantibodies against thyroid peroxidase (TPOAb), thyroglobulin (TGAb), glutamic acid decarboxylase 65 (GADA), Zink transporter 8 (ZnT8R/W/QA), insulinoma-associated protein-2 (IA-2A), insulin (IAA) and HLA-DQ genotypes. Prospectively collected samples from 2 years of age were next analysed for TPOAb, and TGAb and, finally, in confirming samples at 11-16 years of age along with TSH and FT4. Frequencies were tested with Chi-square or Fischer's exact tests, autoantibody levels with Wilcoxon and correlations between autoantibody levels with Spearman's rank correlation test. Results: The prevalence of thyroid autoimmunity was 6.9%, overrepresented in girls (p < .001) also having higher TPOAb levels at 10 years (p = .049). TPOAb was associated with GADA (p = .002), ZnT8R/W/QA (p = .001) and IA-2A (p = .001) while TGAb were associated with ZnT8R/W/QA (p = .021). In boys only, TPOAb were associated with GADA (p = .002), IA-2A (p = .001), ZnT8R/W/QA (p = .001) and IAA (p = .009), and TGAb with GADA (p = .013), IA-2A (p = .005) and ZnT8R/W/QA (p = .003). Levels of IA-2A correlated to both TPOAb (p = .021) and to TGAb (p = .011). In boys only, levels of GADA and TGAb correlated (p = .009 as did levels of IA-2A and TPOAb (p = .013). The frequency and levels of thyroid autoantibodies increased with age. At follow-up, 22.3% had abnormal thyroid function or were treated with thyroxine. Conclusions: Thyroid autoimmunity and high TPOAb levels were more common in girls. In contrast, in boys only, there was a strong association with as well as correlation between levels of thyroid and islet autoantibodies. It is concluded that while girls may develop autoimmune thyroid disease (AITD) independent of islet autoantibodies, the risk for thyroid disease in boys may be linked to concomitant islet autoimmunity. [ABSTRACT FROM AUTHOR]

Cavitation in tuberculosis enables highly efficient person-to-person aerosol transmission. We performed transcriptomics in the rabbit cavitary tuberculosis model. Among 17 318 transcripts, we identified 22 upregulated proteases. Five type I collagenases were overrepresented: cathepsin K (CTSK), mast cell chymase-1 (CMA1), matrix metalloproteinase 1 (MMP-1), MMP-13, and MMP-14. Studies of collagen turnover markers, specifically, collagen type I C-terminal propeptide (CICP), urinary deoxypyridinoline (DPD), and urinary helical peptide, revealed that cavitation in tuberculosis leads to both type I collagen destruction and synthesis and that proteases other than MMP-1, MMP-13, and MMP-14 are involved, suggesting a key role for CTSK. We confirmed the importance of CTSK upregulation in human lung specimens, using immunohistochemical analysis, which revealed perigranulomatous staining for CTSK, and we showed that CTSK levels were increased in the serum of patients with tuberculosis, compared with those in controls (3.3 vs 0.3 ng/mL; P = .005). [ABSTRACT FROM AUTHOR]

Aims: Non-diabetic children with multiple islet autoantibodies were recruited to a secondary prevention trial. The objective was to determine the predictive value of baseline (1) HbA1c and metabolic variables derived from intravenous (IvGTT) and oral glucose tolerance tests (OGTT), (2) insulin resistance and (3) number, type and levels of islet autoantibodies, for progression to type 1 diabetes. Methods: Children [ n = 50, median 5.1 (4-17.9) years] with autoantibodies to glutamate decarboxylase (GAD65A) and at least one of insulinoma-associated protein 2 (IA-2A), insulin or ZnT8 transporter (ZnT8RA, ZnT8WA, ZnT8QA) were screened with IvGTT and OGTT and followed for a minimum of 2 years. Results: Baseline first phase insulin response (sum of serum-insulin at 1 and 3 min during IvGTT; FPIR) ≤3 μU/mL [HR 4.42 (CI 1.40-14.0) p = 0.011] and maximal plasma glucose ≥11.1 mmol/L measured at 30, 60 and/or 90 min during OGTT [HR 6.13 (CI 1.79-21.0) p = 0.0039] were predictors for progression to diabetes. The combination of FPIR from IvGTT and maximal plasma glucose during OGTT predicted diabetes in 10/12 children [HR 9.17 (CI 2.0-42.0) p = 0.0043]. High-level IA-2A, but not number of autoantibodies, correlated to dysglycemia during OGTT ( p = 0.008) and to progression to type 1 diabetes [HR 4.98 (CI 1.09-22.0) p = 0.039]. Conclusions: Baseline FPIR, maximal plasma glucose ≥11.1 at 30, 60 or 90 min during OGTT and high-level IA-2A need to be taken into account when randomizing islet autoantibody positive non-diabetic children to secondary prevention. [ABSTRACT FROM AUTHOR]

In this study, the microbiological food safety of using anaerobic digestate as a fertilizer in hydroponic production of vegetables was evaluated. The used anaerobic digestate was a liquid residue obtained from the digestion of food waste in the production of biogas. Replacing the customary inorganic fertilizer used in hydroponic production with this recycled fertilizer (biofertilizer) could allow for sustainable urban food production close to retailers and consumers. However, in striving for circular food production, it is vital that the food safety of utilizing recycled resources is ensured. Especially in the application of hydroponic farming, where the nutrient loop is shorter than on arable land, a microbiological food safety risk assessment is crucial when adopting new and recycled fertilizers. The biofertilizer based on anaerobic digestate was therefore studied with regard to its microbial community (16S rRNA gene amplicon sequencing) during production of vegetables in a hydroponic system. The biofertilizer was also challenge tested with food borne pathogens (Salmonella enterica , Listeria monocytogenes and Bacillus cereus). Furthermore, the microbial activity of the biofertilizer was studied using isothermal calorimetry. The results showed that the microbial community of the biofertilizer changed distinctly through a necessary initial nitrification process, and that the most abundant genus was Mycobacterium. Deliberate contaminations with 5 log 10 CFU mL−1 of either S. enterica or L. monocytogenes in the nitrified biofertilizer were no longer detectable with selective plating after 48 h of incubation at 20 °C. Selective plating for B. cereus revealed that the biofertilizer contained low levels (∼10 CFU mL−1) of the bacterium, and an inoculation of 5 log 10 CFU mL−1 B. cereus decreased to these levels within 24 h of incubation at 20 °C. Analysis of the microbial activity of the biofertilizer indicated that the biofertilizer does not seem to support microbial activity without the addition of an external nutrient source that contains an accessible carbon source and trace elements. The type of biofertilizer investigated in this study is thus regarded as microbiologically safe for use in hydroponic cultivation. The constant presence of viable B. cereus , however, emphasizes the fundamental importance of continuous risk assessment in case of any modifications or supplementations of the biofertilizer, since it clearly can act as a reservoir for bacterial endospores. [Display omitted] • Mycobacterium is the most abundant genus in nitrified biofertilizer. • Low levels (∼10 CFU mL−1) of B. cereus is naturally present in anaerobic digestate. • Biofertilizer does not support growth of pathogens S. enterica and L. monocytogenes. • The biofertilizer is deemed microbially safe if no external nutrient source is added. [ABSTRACT FROM AUTHOR]

Highlights: [•] Production of advanced biofuels by yeast. [•] Second generation bioethanol. [•] Metabolic engineering of yeast. [•] Production of chemicals by yeast. [ABSTRACT FROM AUTHOR]

The seven WhiB proteins of Mycobacterium tuberculosis (M.tb) are widely believed to be redox-sensing transcription factors due to their binding of iron-sulfur clusters and similarities to DNA binding proteins. Here, we explored the nature of this hypothesized relationship. We exposed M.tb to physiologic conditions such as gradual hypoxia, nitric oxide (NO), cyclic AMP and in vivo conditions, and measured transcription of the whiB genes. We found whiB3 to be induced both by hypoxia and NO, whiB7 to be induced in macrophage-like cells, and whiB4 to be induced in mouse lung. Cyclic AMP induced whiB1,-2, -4, -6 and -7. Our data indicate that the M.tb whiB genes are induced independently by various stimuli which may add versatility to their suggested redox-sensing properties. [ABSTRACT FROM AUTHOR]

Abstract: Previous work on the metabolism of Lactobacillus reuteri ATCC 55730 anticipated a variability in the use of organic electron acceptors as a means to relieve metabolic redox problems. Therefore, investigations focusing on this unique metabolism of L. reuteri may reveal a basis for new probiotic properties. For instance, L. reuteri may use reactive aldehydes and ketones as electron acceptors to balance their redox metabolism, which opens the possibility to exploit this bacterium for in vivo bioreduction of deleterious compounds in the gastrointestinal tract (GIT). Herein we demonstrate that L. reuteri ATCC 55730 cultures on glucose are able to use furfural (1g/L), and hydroxymethylfurfural (HMF) (0.5g/L), as electron acceptors. The former enhances the growth rate by about 25% and biomass yield by 15%, whereas the latter is inhibitory. Furfural is stoichiometrically reduced to furfuryl alcohol by the culture. The conversion of furfural had no effect on the flux distribution between the simultaneously operating phosphoketolase and Embden–Meyerhof pathways, but initiated a flux to acetate production. In addition to furfural and HMF, cellular extracts showed potential to reoxidize NADH and/or NADPH with acrolein, crotonaldehyde, and diacetyl, indicating that conversion reactions take place intracellularly, however, utilization mechanisms for the latter compounds may not be present in this strain. The strain did not reduce other GIT-related reactive compounds, including acrylamide, glyoxal, and furan. [Copyright &y& Elsevier]

We compute the Cramér–Rao lower bounds for determination of isotropic permittivity and permeability in slabs using reflection and transmission data. The results apply to three common measurement situations: free space, rectangular waveguides, and coaxial waveguides. The bounds depend only on the available data and not on the actual inversion method used, making them suitable to evaluate a particular experimental setup. The results are illustrated with several measurements in a rectangular waveguide setting. [ABSTRACT FROM AUTHOR]

This paper describes a method to measure the permittivity and permeability at temperatures from room temperature up to 1000 ^\circ\C using a single rectangular waveguide. The hardware design of the setup that can handle these temperatures, and the procedure that is required to correct the thermal expansion is developed. This includes the sample displacement, the displacement of the calibration reference planes, the thermal expansion of the waveguide, and the gap between the sample and the waveguide wall. Measurements on Macor and NiZn ferrite samples are performed in order to evaluate the performance of the setup and the procedure that is used to determine the permittivity and permeability from the measured S-parameters. [ABSTRACT FROM PUBLISHER]

Louse-borne relapsing fever (LBRF) borreliosis is caused by Borrelia recurrentis, and it is a deadly although treatable disease that is endemic in the Horn of Africa but has epidemic potential. Research on LBRF has been severely hampered because successful infection with B. recurrentis has been achieved only in primates (i.e., not in other laboratory or domestic animals). Here, we present the first non-primate animal model of LBRF, using SCID (-B, -T cells) and SCID BEIGE (-B, -T, -NK cells) immunocompromised mice. These animals were infected with B. recurrentis A11 or A17, or with B. duttonii 1120K3 as controls. B. recurrentis caused a relatively mild but persistent infection in SCID and SCID BEIGE mice, but did not proliferate in NUDE (-T) and BALB/c (wild-type) mice. B. duttonii was infectious but not lethal in all animals. These findings demonstrate that the immune response can limit relapsing fever even in the absence of humoral defense mechanisms. To study the significance of phagocytic cells in this context, we induced systemic depletion of such cells in the experimental mice by injecting them with clodronate liposomes, which resulted in uncontrolled B. duttonii growth and a one-hundred-fold increase in B. recurrentis titers in blood. This observation highlights the role of macrophages and other phagocytes in controlling relapsing fever infection. B. recurrentis evolved from B. duttonii to become a primate-specific pathogen that has lost the ability to infect immunocompetent rodents, probably through genetic degeneration. Here, we describe a novel animal model of B. recurrentis based on B- and T-cell-deficient mice, which we believe will be very valuable in future research on LBRF. Our study also reveals the importance of B-cells and phagocytes in controlling relapsing fever infection. Author Summary: Research on Borrelia recurrentis, the agent of louse-borne relapsing fever (LBRF), has been hampered by the lack of a feasible non-primate animal model. By using immunocompromised SCID mice deficient in B- and T-cells, we were able to establish a stable, persistent B. recurrentis infection with low spirochetemia. Furthermore, systemic depletion of phagocytes by use of clodronate liposomes increased the numbers of bacteria in blood, which demonstrates the importance of both the humoral response and phagocytosis in controlling relapsing fever infection. Lice are favored by the conditions related to the unfortunate turmoil and refugee camps prevailing in the Horn of Africa, and hence LBRF is more important now than it has been for several decades. The newly published genome sequence of B. recurrentis and techniques to genetically manipulate RF borreliae will be instrumental in understanding its complex biology. We therefore believe that our novel animal model will be a great asset that can facilitate future studies of the infection biology of B. recurrentis. [ABSTRACT FROM AUTHOR]

Louse-borne relapsing fever (LBRF) borreliosis is caused by Borrelia recurrentis, and it is a deadly although treatable disease that is endemic in the Horn of Africa but has epidemic potential. Research on LBRF has been severely hampered because successful infection with B. recurrentis has been achieved only in primates (i.e., not in other laboratory or domestic animals). Here, we present the first non-primate animal model of LBRF, using SCID (-B, -T cells) and SCID BEIGE (-B, -T, -NK cells) immunocompromised mice. These animals were infected with B. recurrentis A11 or A17, or with B. duttonii 1120K3 as controls. B. recurrentis caused a relatively mild but persistent infection in SCID and SCID BEIGE mice, but did not proliferate in NUDE (-T) and BALB/c (wild-type) mice. B. duttonii was infectious but not lethal in all animals. These findings demonstrate that the immune response can limit relapsing fever even in the absence of humoral defense mechanisms. To study the significance of phagocytic cells in this context, we induced systemic depletion of such cells in the experimental mice by injecting them with clodronate liposomes, which resulted in uncontrolled B. duttonii growth and a one-hundred-fold increase in B. recurrentis titers in blood. This observation highlights the role of macrophages and other phagocytes in controlling relapsing fever infection. B. recurrentis evolved from B. duttonii to become a primate-specific pathogen that has lost the ability to infect immunocompetent rodents, probably through genetic degeneration. Here, we describe a novel animal model of B. recurrentis based on B- and T-cell-deficient mice, which we believe will be very valuable in future research on LBRF. Our study also reveals the importance of B-cells and phagocytes in controlling relapsing fever infection. [ABSTRACT FROM AUTHOR]

In general, it is believed that fermentation by yeast under harsh industrial conditions, especially if substrates such as wood hydrolysate or lignocellulosic substrates are used, requires the use of so-called industrial strains. In order to check whether this is always true, a comparison of performance was made using two industrial strains and four commonly used laboratory strains, the haploid and diploid versions of CEN-PK and X2180, under industrially relevant stress conditions. The industrial strains were a Swedish commercial baker’s yeast strain and a strain previously isolated from an industrial bioethanol production plant using lignocellulosic substrate. Stress conditions included, apart from growth in the lignocellulosic substrate itself, elevated concentrations of glucose, NaCl, ethanol, and lactate as well as low pH. Results showed that, indeed, the strain adapted to lignocellulosic substrate also possessed the highest growth rate as well as shortest duration of the lag phase in this type of medium. However, the higher the additional stress level, the lower the difference compared to other strains, and X2180 in particular displayed a high resistance to these additional stress conditions. Furthermore, no difference in performance could be detected between the haploid or diploid versions of the laboratory strains. It might be that, at least under some circumstances, a laboratory strain such as X2180 could be an industrially attractive production organism with the advantage of facilitating the possibilities for making controlled genetic manipulations. [ABSTRACT FROM AUTHOR]

The protein kinase C (PKC) isoforms are maintained in an inactive and closed conformation by intramolecular interactions. Upon activation these are disrupted by activators, binding proteins and cellular membrane. We have seen that autophosphorylation of two sites in the C-terminal V5 domain is crucial to keep PKCα insensitive to the activator diacylglycerol, which presumably is caused by a masking of the diacylglycerol-binding C1a domain. Here we demonstrate that the diacylglycerol sensitivity of the PKCβ isoforms also is suppressed by autophosphorylation of the V5 sites. To analyze conformational differences, a fusion protein ECFP-PKCα-EYFP was expressed in cells and the FRET signal was analyzed. The analogous mutant with autophosphorylation sites exchanged for alanine gave rise to a substantially lower FRET signal than wild-type PKCα indicating a conformational difference elicited by the mutations. Expression of the isolated PKCα V5 domain led to increased diacylglycerol sensitivity of PKCα. We identified acidic residues in the VS domain that, when mutated to alanines or lysines, rendered PKCα sensitive to diacylglycerol. Furthermore, mutation to glutamate of four lysines in a lysine-rich cluster in the C2 domain gave a similar effect. Simultaneous reversal of the charges of the acidic residues in the VS and the lysines in the C2 domain gave rise to a PKCα that was insensitive to diacylglycerol. We propose that these structures participate in an intramolecular interaction that maintains PKCα in a closed conformation. The disruption of this interaction leads to an unmasking of the C1a domain and thereby increased diacylglycerol sensitivity of PKCα. [ABSTRACT FROM AUTHOR]

This investigation addresses the following question: what are the important factors for maintenance of a high catabolic capacity under various starvation conditions? Saccharomyces cerevisiae was cultured in aerobic batch cultures, and during the diauxic shift cells were transferred and subjected to 24 h of starvation. The following conditions were used: carbon starvation, nitrogen starvation in the presence of glucose or ethanol, and both carbon starvation and nitrogen starvation. During the starvation period changes in biomass composition (including protein, carbohydrate, lipid, and nucleic acid contents), metabolic activity, sugar transport kinetics, and the levels of selected enzymes were recorded. Subsequent to the starvation period the remaining catabolic capacity was measured by addition of 50 mM glucose. The results showed that the glucose transport capacity is a key factor for maintenance of high metabolic capacity in many, but not all, cases. The results for cells starved of carbon, carbon and nitrogen, or nitrogen in the presence of glucose all indicated that the metabolic capacity was indeed controlled by the glucose transport ability, perhaps with some influence of hexokinase, phosphofructokinase, aldolase, and enolase levels. However, it was also demonstrated that there was no such correlation when nitrogen starvation occurred in the presence of ethanol instead of glucose. [ABSTRACT FROM AUTHOR]

Relapsing-fever borreliosis caused by Borrelia duttonii is a common cause of complications of pregnancy, miscarriage, and neonatal death in sub-Saharan Africa. We established a murine model of gestational relapsing fever infection for the study of the pathological development of these complications. We demonstrate that B. duttonii infection during pregnancy results in intrauterine growth retardation, as well as placental damage and inflammation, impaired fetal circulation, and decreased maternal hemoglobin levels. We show that spirochetes frequently cross the maternal-fetal barrier, resulting in congenital infection. Furthermore, we compared the severity of infection in pregnant and nonpregnant mice and show that pregnancy has a protective effect. This model closely parallels the consequences of human gestational infection, and our results provide insight into the mechanisms behind the complications of pregnancy that have been reported in human relapsing-fever infection. [ABSTRACT FROM AUTHOR]

Abstract: We have shown that protein kinase C (PKC)ε, independently of the catalytic domain, induces outgrowth of cellular processes via its regulatory domain in both neural cells and fibroblasts. This was accompanied by stress fibre loss. Here, we have examined the role of the small GTPases, Rac1, and Cdc42, in these PKC-mediated morphological and cytoskeletal changes. Both constitutively active and dominant negative Rac1 and Cdc42 attenuated the PKC-mediated outgrowth of processes. The suppression was larger for Cdc42 than for Rac1. The PKC-mediated dismantling of the stress fibres in both HiB5 and fibroblasts was inhibited by the expression of the Cdc42 mutants whereas they had smaller effects on the stress fibre dismantling induced by the ROCK inhibitor, Y-27632, indicating a more crucial role for Cdc42 in the PKC-mediated pathway. We conclude that Cdc42 is an important downstream factor in the pathway through which PKC mediates morphological and cytoskeletal effects. [Copyright &y& Elsevier]

Weak organic acids are well-known metabolic effectors in yeast and other micro-organisms. High concentrations of lactic acid due to infection of lactic acid bacteria often occurs in combination with growth under nutrient-limiting conditions in industrial yeast fermentations. The effects of lactic acid on growth and product formation of Saccharomyces cerevisiae were studied, with cells growing under carbon- or nitrogen-limiting conditions in anaerobic chemostat cultures ( D=0.1 h−1) at pH values 3.25 and 5. It was shown that lactic acid in industrially relevant concentrations had a rather limited effect on the metabolism of S. cerevisiae. However, there was an effect on the energetic status of the cells, i.e. lactic acid addition provoked a reduction in the adenosine triphosphate (ATP) content of the cells. The decrease in ATP was not accompanied by a significant increase in the adenosine monophosphate levels. [ABSTRACT FROM AUTHOR]

Abstract: Relapsing fever, an infection caused by Borrelia spirochetes, is generally considered a transient, self-limiting disease in humans. The present study reveals that murine infection by Borrelia duttonii can be reactivated after an extended time as a silent infection in the brain, with no bacteria appearing in the blood and spirochete load comparable to the numbers in an infected tick. The host cerebral gene expression pattern is indistinguishable from that of uninfected animals, indicating that persistent bacteria are not recognized by the immune system nor cause noticeable tissue damage. Silent infection can be reactivated by immunosuppression, inducing spirochetemia comparable to that of initial densities. B. duttonii has never been found in any host except man and the tick vector. We therefore propose the brain to be a possible natural reservoir of the spirochete. The view of relapsing fever as an acute disease should be extended to include in some cases prolonged persistence, a feature characteristic of the related spirochetal infections Lyme disease and syphilis. [Copyright &y& Elsevier]

Abstract: Protein kinase C (PKC) isoforms are central components in intracellular networks that regulate a vast number of cellular processes. It has long been known that in most cell types, one or more PKC isoforms influences the morphology of the F-actin cytoskeleton and thereby regulates processes that are affected by remodelling of the microfilaments. These include cellular migration and neurite outgrowth. This review focuses on the role of classical and novel PKC isoforms in migration and neurite outgrowth, and highlights some regulatory steps that may be of importance in the regulation by PKC of migration and neurite outgrowth. Many studies indicate that integrins are crucial mediators both upstream and downstream of PKC in inducing morphological changes. Furthermore, a number of PKC substrates, directly associated with the microfilaments, such as MARCKS, GAP43, adducin, fascin, ERM proteins and others have been identified. Their potential role in PKC effects on the cytoskeleton is discussed. [Copyright &y& Elsevier]

The yeast Saccharomyces cerevisiae predominantly ferments glucose to ethanol at high external glucose concentrations, irrespective of the presence of oxygen. In contrast, at low external glucose concentrations and in the presence of oxygen, as in a glucose-limited chemostat, no ethanol is produced. The importance of the external glucose concentration suggests a central role for the affinity and maximal transport rates of yeast's glucose transporters in the control of ethanol production. Here we present a series of strains producing functional chimeras between the hexose transporters Hxt1 and Hxt7, each of which has distinct glucose transport characteristics. The strains display a range of decreasing glycolytic rates resulting in a proportional decrease in ethanol production. Using these strains, we show for the first time that at high glucose levels, the glucose uptake capacity of wild-type S. cerevisiae does not control glycolytic flux during exponential batch growth. In contrast, our chimeric Hxt transporters control the rate of glycolysis to a high degree. Strains whose glucose uptake is mediated by these chimeric transporters will undoubtedly provide a powerful tool with which to examine in detail the mechanism underlying the switch between fermentation and respiration in S. cerevisiae and will provide new tools for the control of industrial fermentations. [ABSTRACT FROM AUTHOR]

We have previously seen that protein kinase C (PKC) ε induces neurite outgrowth and that PKCδ and PKCθ elicit apoptosis in neuroblastoma cells. In this study we investigate the effects of cell-permeable C2-ceramide on these events in SK-N-BE(2) neuroblastoma cells. C2-ceramide abolishes neurite formation induced by overexpression of PKCε and, in cells over- expressing PKCδ or PKCθ, ceramide treatment leads to apoptosis. Exposure to C2-ceramide also suppressed neurite outgrowth induced by retinoic acid, but ceramide did not abrogate neurite induction by treatment with the ROCK inhibitor Y-27632, demonstrating that C2-ceramide is not a general inhibitor of neurite outgrowth. The neurite-suppressing effect occurs independently of cell-death. Furthermore, C2-ceramide relocated PKCε and the isolated regulatory domain of PKCε from the cytosol to the perinuclear region. In contrast, neither the localization of PKCδ nor of PKCθ was affected by C2-ceramide. Taken together, the data indicate that the neurite-inhibiting effect of C2-ceramide treatment may be caused by a re-localization of PKCε and thus identify a functional consequence of ceramide effects on PKCe localization. [ABSTRACT FROM AUTHOR]

Seven different strains of Saccharomyces cerevisiae were tested for the ability to maintain their fermentative capacity during 24 h of carbon or nitrogen starvation. Starvation was imposed by transferring cells, exponentially growing in anaerobic batch cultures, to a defined growth medium lacking either a carbon or a nitrogen source. After 24 h of starvation, fermentative capacity was determined by addition of glucose and measurement of the resulting ethanol production rate. The results showed that 24 h of nitrogen starvation reduced the fermentative capacity by 70 to 95%, depending on the strain. Carbon starvation, on the other hand, provoked an almost complete loss of fermentative capacity in all of the strains tested. The absence of ethanol production following carbon starvation occurred even though the cells possessed a substantial glucose transport capacity. In fact, similar uptake capacities were recorded irrespective of whether the cells had been subjected to carbon or nitrogen starvation. Instead, the loss of fermentative capacity observed in carbon-starved cells was almost surely a result of energy deprivation. Carbon starvation drastically reduced the ATP content of the cells to values well below 0.1 µmol/g, while nitrogen-starved cells still contained approximately 6 µmol/g after 24 h of treatment. Addition of a small amount of glucose (0.1 g/liter at a cell density of 1.0 g/liter) at the initiation of starvation or use of stationary-phase instead of log-phase cells enabled the cells to preserve their fermentative capacity also during carbon starvation. The prerequisites for successful adaptation to starvation conditions are probably gradual nutrient depletion and access to energy during the adaptation period. [ABSTRACT FROM AUTHOR]

Background: The acquisition of drug resistance is a major reason for poor outcome of neuroblastoma. Protein kinase C (PKC) has been suggested to influence drug resistance in cancer cells. The aim of this study was to elucidate whether inhibition of PKCβ isoforms influences drug-resistance of neuroblastoma cells. Methods: The effect of the PKCβ inhibitor LY379196 on the growth-suppressing effects of different chemotherapeutics on neuroblastoma cells was analyzed with MTT assays. The effect of LY379196 on the accumulation of [3H]vincristine was also investigated Results: The PKCβ inhibitor LY379196 suppressed the growth of three neuroblastoma cell lines. LY379196 also augmented the growth-suppressive effect of doxorubicin, etoposide, paclitaxel, and vincristine, but not of carboplatin. The effect was most marked for vincristine and for the cell-line (SK-N-BE(2)) that was least sensitive to vincristine. No effect was observed on the non-resistant IMR-32 cells. Two other PKC inhibitors, Gö6976 and GF109203X, also enhanced the vincristine effect. The PKC inhibitors caused an increased accumulation of [3H]vincristine in SK-N-BE(2) cells. Conclusions: This indicates that inhibition of PKCβ could attenuate multidrug resistance in neuroblastoma cells by augmenting the levels of natural product anticancer drugs in resistant cells. [ABSTRACT FROM AUTHOR]

Product concentrations may be estimated from gas analysis or calorimetric measurements. These techniques of analysis are fast, simple, and provide a continuous output. To check the accuracy of these estimations, the anaerobic ethanol formation of an industrial strain of the yeast Saccharomyces cerevisiae was selected as a test system. Cultivations were carried out as batch cultures with different nitrogen sources (ammonium, glutamate and a mixture of amino acids) and 20 g/l of glucose as the carbon and energy source. The results showed that there was a good agreement between measured and calculated ethanol values. However, especially when using heat data the results are very sensitive to small changes in the stoichiometry of the catabolic reaction, i.e. ethanol is not the only product but there are also minor amounts of glycerol and acetate. The problems generated by these products when using heat data to calculate ethanol concentrations are discussed in detail. [Copyright &y& Elsevier]

We have previously demonstrated that long-term ethanol treatment increased the number and function of muscarinic acetylcholine receptors (mAChRs) in human neuroblastoma cells, but the molecular mechanisms involved in these changes are unknown. In the present study, the effect of protein kinase C (PKC) on these events was investigated in human neuroblastoma SH-SY5Y cells. Following exposure to 100 mM ethanol for 2 days, both [3H]N-methylscopolamine binding and carbachol-stimulated I(1,4,5)P3 formation were increased. When cells were cultured in the presence of 12-O-tetradecanoylphorbol 13-acetate (TPA), a potent activator of PKC, the effects of ethanol on mAChR number were totally inhibited but ethanol still potentiated carbacholstimulated I(1,4,5)P3 formation in TPA treated cells. TPA dose-dependently inhibited carbochol-stimulated I(1,4,5)P3 formation and this effect appeared to be independent of PKC phosphorylating activity. On the other hand, PKC inhibitors mimicked ethanol effects on mAChR number and function. Selective inhibition of classical PKC isozymes with 1 muM Go 6976 for 2 days caused an increase in mAChR number and function, suggesting a role for these isozymes in ethanol-induced upregulation of mAChRs. These data indicate that longterm ethanol treatment may upregulate the number of mAChRs by counteracting PKC-mediated phosphorylation. The effects of ethanol on receptor-coupled phosphoinositide hydrolysis appear to be independent of PKC activity. [ABSTRACT FROM AUTHOR]

Examines the use of prolepses on the novels of writer Peter Carey. Definition of prolepsis; Views on the works of Carey; Impact of prolepsis on Carey's novels.

Chlorophyf l‐free preparations of plasma membranes from leaves of barley (Hordeum vulgare L. cv. Kristina) and spinach (Spinada oleracea L. cv. Viking II) were obtained by partition in an aqueous dextran‐polyethylene glycol two‐phase system. CJlu‐can synthetase II (EC 2.4,1.34), a marker for the plasma membrane, was highly enriched in both preparations. Silicotungstic acid, a specific stain for the plasma membrane, indicated a purity close to 100% for the barley preparation. Both plasma membrane preparations contained a light‐reducible b‐cytochrome, as shown by low temperature spectroscopy. The plasma membranes had a tow protein content compared to the bulk of intracellular membranes. The polypeptide composition of the barley and spinach plasma membranes showed striking similarities, with.the most prominent polypeptides in the 49‐58 kdalton region, and some further prominent bands in the 30 kcialton region. Some high molecular weight polypeptides in the 73‐110 kdalton region were also typical for the plasma membranes compared to the microsomal fractions. [ABSTRACT FROM AUTHOR]

Purified mesophyll protoplasts from the C4 plant Digitaria sanguinalis were used to prepare intact mesophyll chloroplasts with low cytoplasmic contamination. The procedure involved breakage of protoplasts, differential centrifugation, partition in a dextran-polyethylene glycol two-phase system, and Percoll density gradient centrifugation. The final chloroplast preparation contained about 80% intact chloroplasts with a phosphoenolpyruvate carboxylase contamination of 0.2-1% of the original protoplast activity, corresponding to 1-6 μmo1 14CO2 fixed/mg Chl.h. The purified chloroplasts showed substrate-dependent oxygen evolution in the range of 40-150 μmol substrate reduced/mg Chl.h, with phosphoglycerate or oxaloacetate as substrate. Both reactions were stimulated 1.5 fold by pyruvate and further by addition of the other substrate. These measurements indicated that phosphoglycerate reduction was limited by substrate transport across the chloroplast envelope. Without added substrate, the chloroplasts consumed oxygen via pseudo-cyclic electron transport in the light. Also this reaction was stimulated by pyruvate. Phosphoglycerate-dependent oxygen evolution was inhibited by P1 and by phosphoenolpyruvate to about the same extent with purified chloroplasts, but only by P1 with protoplast extracts. This suggests that phosphoglycerate, P1 and phosphoenol-pyruvate share a common carrier, similar to the P1-translocator in C3 chloroplasts, and that the lack of inhibition obtained with phosphoenolpyruvate and unpurified chloroplasts is artefactual, possibly due to oxaloacetate formation from added phosphoenolpyruvate and concomitant stimulation of oxygen evolution by oxaloacetate reduction. Furthermore, the results suggest that phosphoenolpyruvate is transported with a Km similar to that of P1 in C4 mesophyll chloroplasts, [ABSTRACT FROM AUTHOR]

Antibodies (rabbit) have been prepared against total stroma from isolated spinach (Spinacia oleracea L. cv. Viking II) chloroplasts. These antibodies inhibited most of the aldolase activity present outside the chloroplasts in preparations of intact (80-95%) chloroplasts. They also reduced the amount of labelled fructose-1,6-bisphosphate found in the medium after 14CO2 fixation with such preparations. Both intact and broken chloroplasts were strongly agglutinated by the antibodies. The results indicate that the external fructose-1,6-bisphosphate was formed from excreted dihydroxyacetone phosphate by the action of aldolase and those phosphate isomerase present outside the chloroplasts. The contamination of organelle preparations with free enzymes or enzymes adsorbed on the outer surface of the organelles is probably a general phenomenon. It is suggested that antibodies can he used as a tool to detect and selectively inhibit such contaminating enzyme activities. [ABSTRACT FROM AUTHOR]

The compartmentation of 14CO2 fixation and concomitant metabolism of 14C‐labelled products in a recombined system, composed of isolated intact spinach (Spinacia oleracea) chloroplasts and a ‘cytoplasm’ fraction, has been studied. Addition of ‘cytoplasm’ to chloroplasts fixing 14CO2 increased the label in hexose monophosphates outside the chloroplasts at the expense of excreted dihydroxyacetone phosphate. The label in ammo acids was increased both inside and outside the chloroplasts. The results support the view that chloroplasts are not able to make 2‐oxoacids for amino acid synthesis directly from fixed CO2, but have to co‐operate with the cytoplasm and other organelles. The results also show that recombined systems can be useful for studies on the compartmentation of carbon metabolism in photosynthesizing plant tissues. [ABSTRACT FROM AUTHOR]

The three enzymes D-3-phosphoglycerate dehydrogenase (E.C. 1.1.1 .s), glutamate dependent O-phospho-L-serine amino-transferase (E.C. 2.6.1.52), and O-phospho-L-serine phosphatase (E.C. 3.1.3.3.), which together catalyse the turnover of D-3-phosphoglycerate (3-PGA) to serine were assayed in chloroplast and leaf extracts from spińach (Spinacia oleracea). Relatively high activities of the dehydrogenase and the phosphatase were found in both chloroplast and leaf extracts, whereas the specific activity of the aminotransferase was 10 times higher in leaf extracts than in chloroplast extracts. The results suggest that spinach chloroplasts are able to produce minor amounts of serine directly from 3-PGA, but that the main part of the phosphohydroxypyruvate formed is exported, and probably used in a parallel pathway to serine outside the chloroplasts. Some kinetic properties of the enzymes were also determined. [ABSTRACT FROM AUTHOR]

The effect of ethanol on the characteristics of carbachol-stimulated release of Ca2+ from intracellular Ca2+ stores was studied in single SH-SY5Y cells. Stimulation with carbachol, in the absence of extracellular Ca2+, elicited a rapid Ca2+ increase in SH-SY5Y cells peaking within seconds after addition of maximal agonist concentration. The Ca2+ response pattern in single cells resembled the population response, and there was no evidence of oscillatory changes in cytosolic [Ca2+] ([Ca2+]i). However, cell-to-cell variability could be detected in the magnitude and the latency time of the response, and in the rate of [Ca2+]i increase. In a carbachol dose-response analysis, the EC50 for the number of responsive cells and for the peak [Ca2+]i response was lower than that for carbachol-induced inositol 1,4,5-trisphosphate formation by a factor of 5 to 50. Ethanol (100 mM) caused a significant suppression of the number of responsive cells, but only when cells were stimulated with nonsaturating carbachol concentrations (1 and 10 μM). The suppression by ethanol was evident primarily in those cells that gave a Ca2+ response after several seconds of stimulation, whereas cells that responded within the initial seconds of receptor stimulation remained relatively unaffected. In responding cells stimulated with 10 μM carbachol, ethanol exposure also suppressed the maximal Ca2+ increase primarily in those cells that responded late. We suggest that ethanol suppression of muscarinic receptor-mediated signal transduction through the phospholipase C pathway may depend on the potentiation of feedback inhibition that requires receptor stimulation. [ABSTRACT FROM AUTHOR]

Examines the influence of different nitrogen sources on the growth and product formation of an industrial strain of `Saccharomyces cerevisiae.' Medium composition; Scheme for the formation of reducing equivalents in the biosynthesis of amino acids; Formation of biomass and extracellular metabolites; Growth characteristics; Biomass composition.

Investigates the relationship between male plumage and male parental care in yellowhammers, Emberiza citrinella. Factors which affect the amount and quality of male parental care; Female species' consideration in the choice of male partners; Correlation between male and female feeding rates; Sexual selection process among yellowhammers.

The plant plasma membrane contains a 1,3-β-glucan synthase (EC 2.4.1.34) which has its active site on the cytoplasmic side of the membrane, while the product, the cell wall component callose, is deposited on the apoplastic side of the membrane. This enzyme should therefore be an integral, transmembrane protein. The activity of the enzyme is stimulated by Ca2+, polyamines, and polyols. Using sealed, inside-out (cytoplasmic side out) plasma membrane vesicles from sugar beet (Beta vulgaris L.) leaves, which permits the activity to be measured without solubilization of the membrane, we have localized the activator sites for Ca2+, spermine, and cellobiose to the cytoplasmic side of the plasma membrane. [ABSTRACT FROM AUTHOR]

We have estimated the amount of inside-out plasma membrane (PM) vesicles in microsomal fractions from wheat (Triticum aestivum L. cv. Drabant) and maize (Zea mays L.) roots; non-latent activities of the PM markers vanadate-inhibited K+, Mg2+-ATPase (ΔVO4-ATPase) and glucan synthase II (GS II, EC 2.4.1.34) were used as markers for inside-out PM vesicles, latent activities as markers for right-side-out PM vesicles, and specific staining with silicotungstic acid (STA) as a general marker for the PM. Separation of presumptive inside-out PM vesicles from right-side-out ones was achieved by counter-current-distribution (CCD) in an aqueous polymer two-phase system. Most of the GS II activity was latent and was found in material partitioning into the upper phase; a distribution which correlated well with that of STA-stained vesicles. Thus, most of the PM vesicles had a right-side-out orientation. ΔVO4-ATPase, on the other hand, had a dual distribution (particularly pronounced in wheat) and was recovered both in material partitioning into the lower phase and into the upper phase. This indicates that ΔVO4-ATPase activity was present also in membranes other than the PM. Additional evidence for this interpretation came from sucrose gradient centrifugation of wheat root material. This produced two peaks of ΔVO4-ATPase activity with the membranes partitioning into the lower phase, none of which coincided with the peak obtained with right-side-out PM vesicles. Taken together, these results indicate that only very few inside-out PM vesicles arc present in the microsomal fraction, and that ΔVO4-ATPase as a marker for the PM, in contrast to GS II, may give quite misleading results with some plant materials. This stresses the need to use well-defined preparations of sealed, inside-out PM vesicles in solute uptake studies. The distribution of Ca2+-inhibited ATFase, on the other hand, agreed well with those of GS II and STA-stained vesicles both after CCD and sucrose gradient centrifugation, which suggests that Ca2+ inhibition may be a more specific property of the PM H+-ATPase than vanadate inhibition. [ABSTRACT FROM AUTHOR]

The cytochrome composition of plasma membranes (PM) obtained by phase partitioning of microsomal fractions from spinach leaves (Spinacea oleracea L. cv. Medania), cauliflower inflorescences (Brassica oleracea L.), sugar beer leaves (Beta vulgaris L.) and barley (Hordeum vulgare L. cv. Kristina) roots and leaves was characterized by absorbance difference spectrophotometry at different reducing conditions at 20 and – 196°C, by redox titration, and by heme staining of polypeptide bands after lithium dodecyl sulfate polyacrylamide gel electrophoresis (LDS‐PAGE). The location of the α‐bands in the difference spectra and the loss of heme after treatment with LDS indicated that predominantly cytochromes of the b‐type were present in all species tested. The total concentration of cytochrome was ca 0.35 nmol (mg protein)−1. The main component (ca 70% of total) was completely reduced by ascorbate and partly by NADH and had a midpoint potential of ca 150 mV. At – 196°C, ascorbate reduction revealed a symmetrical α‐band at ca 557 nm with PM from spinach leaves, cauliflower and sugar beet leaves, but with barley root and leaf PM ascorbate reduction resulted in an asymmetrical α‐band (shoulder at 552, maximum at 559 nm). In the dithionite‐reduced minus ascorbate‐reduced spectrum at –196°C a split α‐band (552 + 558 nm) was seen with PM from all species. This minor component had a midpoint potential of ca – 50 mV and is probably identical to cytochrome b5, the presence of which would explain the relatively high NADH‐cytochrome c reductase activities observed with plant PM. With PM from cauliflower, CO‐difference spectra indicated that cytochromes P‐420 and P‐450 were present at concentrations up to 0.06 and 0.03 nmol (mg protein)−1, respectively. Visualization of cytochromes by heme staining after LDS‐PAGE was complicated by endogenous peroxidase activity and by loss of heme during solubilisation. A presumptive b‐cytochrome (heme‐stained band at 94 kDa) was only detected with barley leaf PM. [ABSTRACT FROM AUTHOR]

Plasma membranes were isolated from light-grown, 14-day-old maize leaves (Zea mays L. cv. Golden Cross Bantam) using aqueous two-phase partitioning. The plasma membrane (PM) fraction contained < 0.3% of the total chlorophyll, < 0.2% of the mitochondrial marker enzyme activity, minimal contamination by endomembranes and 34% of the total PM. A calmodulin-sitmulated (Ca2+ + Mg2+)-ATpase was identified in the PM-enriched fraction. The Ca2+ + calmodulin stimulation was dependent of Mg2+, saturated at ca 25 μM total Ca2+, had a pH maximum at 7.2 and was maximally stimulated by 600 nM bovine brain calmodulin. The stimulation was not greatly affected by the anion present and showed a divalent cation specificity of Ca2+ > Sr+2 ≥ Mn+2 > Co2+ ≥ Cu2+ > Ba2+. The napthalenesulfonamide W7, an antagonist of calmodulin action, completely inhibited the calmodulin stimulation at 175 μM, while the less active analogue W5 was ineffective at this concentration. La3+, an inhibitor of PM Ca2+ transport, showed a 50% inhibition of calmodulin-stimulated ATPase activity at ca 200 μM. Taken as a whole, these date demonstrate the presence of a calmodulin-stimulated, (Ca2+ + Mg2+)-ATPase on the cytoplasmic surface of the plasma membrane of maize leaf cells. [ABSTRACT FROM AUTHOR]

An NAD(P)H oxidase activity stimulated by phenolic compounds has been investigated in purified plasma membranes (pm) and in an intracellular membrane (icm) fraction depleted in plasma membranes, both obtained from a microsomal fraction from cauliflower inflorescences (Brassica oleracea L.). The phenolic compounds salicylhydroxamic add (SHAM), ferulic acid, coniferyl alcohol, n-propyl gallate, naringenin, kaempferol and caffeic acid all strongly stimulated the activity. Peroxidase (EC 1.11.1.7). or a peroxidase-like enzyme, was responsible for the NAD(P)H oxidase activity, which proceeded through a free-radical chain reaction and was inhibited by catalase (EC 1.11.1.6), superoxide dismutase (EC 1.15.1.1) and KCN. Most of the total activity was soluble; however, the membrane-bound activity was highly enriched in the pm compared to the km. The catalase activity was 6 times higher in the icm-Fraction than in the pm-fraction, but this was not the reason for the much lower phenol-stimulated NADH oxidase activity in the km. Peroxidase activity measured with o-dianisidine and H2O2 had about the same specific activities in the pm-and icm- fractions. Neither the phenol-stimulated NADH oxidase nor the peroxidase activity could be washed away from the pm even by 0.7 M NaCl, indicating that these activities are truly membrane-bound. SHAM as well as the other phenolic compounds capable of stimulating the NADH oxidase reaction were potent inhibitors of blue light-induced cytochrome b-reduction in the pm fraction. [ABSTRACT FROM AUTHOR]

The ability of chloroplasts to synthesize aromatic amino acids from CO2 was investigated using highly purified, intact spinach (Spinacia oleracea L. cv. Viking II) chloroplasts and 14CO2. Incorporation of 14C into aromatic amino acids was very low, however, and this was assumed to be due to lack of phosphoenolpyruvate (PEP), one of the substrates for the shikimate/arogenate pathway leading to aromatic amino acids in chloroplasts. Therefore, the glycolytic enzymes phosphoglycerate mutase (EC 2.7.5.3) and enolase (EC 4.2.1.11) were added to the 14CO2 fixation medium in order to convert labelled 3‐phosphoglycerate exported from the intact chloroplasts to 2‐phosphoglycerate and PEP. In this way a part of the glycolytic pathway was reconstituted outside the chloroplasts to substitute for the cytoplasm lost on isolation. The presence of both enzymes in the medium increased incorporation of 14C into Tyr and Phe more than ten‐fold and incorporation into Trp about two‐fold, while total 13CO2 fixation rates were not affected. Our results suggest that chloroplasts do not contain phosphoglycerate mutase or enolase, and that, in vivo, PEP is synthesized in the cytoplasm and imported to the chloroplast stroma for the biosynthesis of aromatic amino acids. The biosynthesis of all three aromatic amino acids was under feedback control. Using expected physiological concentrations (below 100 μM), each of the aromatic amino acids exerted a strict feedback inhibition of its own biosynthesis only. [ABSTRACT FROM AUTHOR]

Presents a chemostat study conducted by correlating glycolytic flux with adenosine triphosphate concentration in Saccharomyces cerevisiae. Investigation of the levels of intracellular nucleotides and glycolytic enzymes at different glycopytic fluxes; Determination of whether there is a correlation between any of these concentrations; How changes in catabolic flux affected the accumulation of the storage carbohydrates glycogen and trehalose.

Investigates the smoking and intermediate alpha-antitrypsin deficiency and lung function in middle-aged men in Maimo, Sweden. Evaluation of lung function in a sample of 50-year-old men; Pulmonary function of non-smoking subjects and controls; Interaction of smoking and alpha-antitrypsin levels in the development of emphysema.

Abstract: Like several other spirochetes, relapsing fever Borrelia can cause persistent infection of the central nervous system (CNS). By treating mice harboring residual Borrelia duttonii brain infection with the bacteriocidal, cell wall inhibiting antibiotic ceftriaxone, bacteria were cleared from the brain. This shows that the residual infection is not latent but actively growing. [Copyright &y& Elsevier]

This study was undertaken to investigate the impact of culture pH (4.5–6.5) and temperature (32–37 °C) on the stress resilience of Lactobacillus reuteri DSM 17938 during freeze-drying and post freeze-drying exposure to low pH (pH 2) and bile salts. Response-surface methodology analysis revealed that freeze-drying survival rates N c e l l s a f t e r d r y i n g N c e l l s b e f o r e d r y i n g 100 were linearly related to pH with the highest survival rate of 80% when cells were cultured at pH 6.5 and the lowest was 40% when cells were cultured at pH 4.5. The analysis further revealed that within the chosen temperature range the culture temperature did not significantly affect the freeze-drying survival rate. However, fermentation at pH 4.5 led to better survival rates when rehydrated cells were exposed to low pH shock or bile salts. Thus, the effect of pH on freeze-drying survival was in contrast to effects on low pH and bile salts stress tolerance. The rationale behind this irreconcilability is based on the responses being dissimilar and are not tuned to each other. Culturing strain DSM 17938 at pH values higher than 5.5 could be a useful option to improve the survivability and increase viable cell numbers in the final freeze-dried product. However, the dissimilar responses for the process- and application parameters tested here suggest that an optimal compromise has to be found in order to obtain the most functional probiotic product possible. [ABSTRACT FROM AUTHOR]

Breast cancer prognosis is frequently good but a substantial number of patients suffer from relapse. The death receptor ligand TRAIL can in combination with Smac mimetics induce apoptosis in some luminal-like ER-positive breast cancer cell lines, such as CAMA-1, but not in MCF-7 cells. Here we show that TRAIL and the Smac mimetic LCL161 induce non-canonical NF-κB and IFN signaling in ER-positive MCF-7 cells and in CAMA-1 breast cancer cells when apoptosis is blocked by caspase inhibition. Levels of p52 are increased and STAT1 gets phosphorylated. STAT1 phosphorylation is induced by TRAIL alone in MCF-7 cells and is independent of non-canonical NF-κB since downregulation of NIK has no effect. The phosphorylation of STAT1 is a rather late event, appearing after 24 hours of TRAIL stimulation. It is preceded by an increase in IFNB1 mRNA levels and can be blocked by siRNA targeting the type I IFN receptor IFNAR1 and by inhibition of Janus kinases by Ruxolitinib. Moreover, downregulation of caspase-8, but not inhibition of caspase activity, blocks TRAIL-mediated STAT1 phosphorylation and induction of IFN-related genes. The data suggest that TRAIL-induced IFNB1 expression in MCF-7 cells is dependent on a non-apoptotic role of caspase-8 and leads to autocrine interferon-β signaling. [ABSTRACT FROM AUTHOR]

Introduction: Low serum selenium and altered tumour RNA expression of certain selenoproteins are associated with a poor breast cancer prognosis. Selenoprotein expression stringently depends on selenium availability, hence circulating selenium may interact with tumour selenoprotein expression. However, there is no matched analysis to date. Methods: This study included 1453 patients with newly diagnosed breast cancer from the multicentric prospective Sweden Cancerome Analysis Network – Breast study. Total serum selenium, selenoprotein P and glutathione peroxidase 3 were analysed at time of diagnosis. Bulk RNA-sequencing was conducted in matched tumour tissues. Fully adjusted Cox regression models with an interaction term were employed to detect dose-dependent interactions of circulating selenium with the associations of tumour selenoprotein mRNA expression and mortality. Results: 237 deaths were recorded within ~ 9 years follow-up. All three serum selenium biomarkers correlated positively (p < 0.001). All selenoproteins except for GPX6 were expressed in tumour tissues. Single cell RNA-sequencing revealed a heterogeneous expression pattern in the tumour microenvironment. Circulating selenium correlated positively with tumour SELENOW and SELENON expression (p < 0.001). In fully adjusted models, the associations of DIO1, DIO3 and SELENOM with mortality were dose-dependently modified by serum selenium (p < 0.001, p = 0.020, p = 0.038, respectively). With increasing selenium, DIO1 and SELENOM associated with lower, whereas DIO3 expression associated with higher mortality. Association of DIO1 with lower mortality was only apparent in patients with high selenium [above median (70.36 µg/L)], and the HR (95%CI) for one-unit increase in log(FPKM + 1) was 0.70 (0.50–0.98). Conclusions: This first unbiased analysis of serum selenium with the breast cancer selenotranscriptome identified an effect-modification of selenium on the associations of DIO1, SELENOM, and DIO3 with prognosis. Selenium substitution in patients with DIO1-expressing tumours merits consideration to improve survival. [ABSTRACT FROM AUTHOR]

Bladder cancer is molecularly one of the most heterogenous malignancies characterized by equally heterogenous clinical outcomes. Standard morphological assessment with pathology and added immunohistochemical analyses is unable to fully address the heterogeneity, but up to now treatment decisions have been made based on such information only. Bladder cancer molecular subtypes will likely provide means for a more personalized bladder cancer care. To facilitate further development of bladder cancer molecular subtypes and clinical translation, the UROSCAN-biobank was initiated in 2013 to achieve systematic biobanking of preoperative blood and fresh frozen tumor tissue in a population-based setting. In a second phase, we established in 2018 a parallel logistic pipeline for molecular profiling by RNA-sequencing, to develop and validate clinical implementation of molecular subtyping and actionable molecular target identification in real-time. Until June 2021, 1825 individuals were included in the UROSCAN-biobank, of which 1650 (90%) had primary bladder cancer, 127 (7%) recurrent tumors, and 48 (3%) unknown tumor status. In 159 patients, multiple tumors were sampled, and metachronous tumors were collected in 83 patients. Between 2016 and 2020 the UROSCAN-biobanking included 1122/2999 (37%) of all primary bladder cancer patients in the Southern Healthcare Region. Until June 2021, the corresponding numbers subjected to RNA-sequencing and molecular subtyping was 605 (UROSCANSEQ), of which 52 (9%) samples were not sequenced due to inadequate RNA-quality (n = 47) or technical failure/lost sample (n = 5). The UROSCAN-biobanking and UROSCANSEQ-infrastructure for molecular subtyping by real-time RNA-sequencing represents, to our knowledge, the largest effort of evaluating population-wide molecular classification of bladder cancer. [ABSTRACT FROM AUTHOR]