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Lobsters are fished world-wide due to their status as a high value, luxury seafood. A large proportion of the product is sold via live export, with lobsters subject to a range of stressors during holding post-capture. Improving the current understanding of the immune response to these stressors assists in improving efficiency and reducing loss in the chain between capture and consumption. In this study, the immune status of four treatment groups of Southern Rock Lobster (Jasus edwardsii) were studied: controls recently landed from a fishing boat, lobsters displaying advanced shell necrosis, lobsters in an unexplained moribund state and lobsters held in a processing facility for 10 weeks in standard conditions (i.e. high density, fasted). A total of 15 immune parameters and 19 haemolymph biochemical parameters were assayed. Phenoloxidase activity was only sporadically observed in haemocyte lysate and was consistently observed at a low level in the plasma with no difference between treatments for either. Haemocyte lysate prophenoloxidase activity was detected in most individuals, with no differences found between treatments. Prophenoloxidase in the plasma showed the highest level of activity, with the shell necrosis treatment demonstrating an elevated activity level relative to the other three treatments. Cell viability was not affected in any treatment. Lobsters with shell necrosis had a reduced capacity for phagocytosis, a significantly higher total haemocyte count, fewer hyalinocytes and more granulocytes and semigranulocytes. Fasted lobsters showed an opposite shift, with significantly more hyalinocytes compared to the other treatments and very few granulocytes and semigranulocytes. The balance of a range electrolytes, minerals metabolites and enzymes were affected in shell necrosis and fasted treatments, raising them as potential markers for immunocompromised lobsters. Multivariate analysis of all assayed parameters showed that all individuals in the necrosis treatment showed a similar, distinct immune response and that the fasted treatment, along with one control and one moribund individual, showed a separate intermediate response. The remainder of the control and moribund lobsters demonstrated a distinct "non-response" in comparison. These results offer a characterisation of the physiological response to common challenges during post-capture holding of rock lobsters, demonstrating the differential response to pathogenic bacterial infection, long term fasting, non-specific moribundity and the stress of capture and transport. • The haemolymph of Southern Rock Lobsters was analysed, comparing 15 immune response parameters and 19 biochemistry parameters. • Treatments clustered into two distinct categories, "response" or "non-response". • Lobsters with shell necrosis and fasted lobsters demonstrated two distinct types of response. • Control lobsters and some lobsters suffering an unexplained moribundity demonstrated non-response. • Activity of the phenoloxidase system was mainly comprised of prophenoloxidase and was observed primarily in the plasma. • Haemocyte cell populations and immune function shifted in response to treatments. [ABSTRACT FROM AUTHOR]

The chlorophyll cycle is a metabolic pathway in plants and green algae that interconverts chlorophyll a and chlorophyll b. The chlorophyll a-to-b conversion is catalyzed by a Rieske-type oxygenase, chlorophyll(ide) a oxygenase, while the chlorophyll b-to-a conversion is catalyzed in two steps by chlorophyll b reductase (a short-chain dehydrogenase) and 7-hydroxymethyl chlorophyll a reductase (a flavoprotein). The level of chlorophyll(ide) a oxygenase is regulated in a feedback loop by the accumulation of chlorophyll b in plants. In contrast, chlorophyll b reductase levels are regulated by a pool of light-harvesting complexes (LHC) that are energetically uncoupled to the core complexes of photosystems. Experimental evidence suggests that LHC levels in plants are regulated by chlorophyll b biosynthesis. LHC levels, however, appear to be independent of chlorophyll b in green algae. Instead, Prasinophytes, a group of green algae, have a chlorophyllide a oxygenase protein possessing structural alterations that differ dramatically from the rest of the green algae, which appear to boost chlorophyll b biosynthesis in these organisms. Hypothetical scenarios for the evolution of the chlorophyll cycle are presented. [ABSTRACT FROM AUTHOR]

The work was piloted to increase the yield and efficacy of rice farming through introduction of induce defense through Salicylic Acid derivative Methyl Salicylate (MeSA) against rice pest to help the growing world with food security. Induced resistance by MeSA could be an applied tool for the regulation of pests to reduce the broad dependence upon insecticides. The effect of MeSA at 100 mg/L exhibited greater mortality against the rice leaffolder. Growth and development of C. medinalis was directly affected altering rates of ingestion, leaf area damage, stadia weights and development time, pupation, and successful pupation to adults were quantified. Significantly decrease existed experimentally when 75 mg/L of MeSA was applied compared to controls. In both fecundity and hatchability, increased concentrations of MeSA, were correlated with decreased number and success. MeSA influenced nutrition indices negatively in a dose dependent manner. The result showed considerable increase in peroxidase activity of C. medinalis infestation after exogenous application of MeSA treatments. Statistical analysis showed substantial reduction in levels of proteins and lipids in C. medinalis post feeding on MeSA treated rice plants at the highest treatment concentration. The data showed that MeSA affected the gut activities along with reduction in enzyme activities (LDH, ACP, ALP and ATPase). Over all treatment with MeSA resulted in significantly lower survival rates of the rice leaffolder. These results illustrate that MeSA improves the rice resistance to the rice leaffolder through disruption of feeding physiology and may have a significant role in the protection of rice from the pest. [ABSTRACT FROM AUTHOR]

Diabetes can cause serious health complications, which can affect every organ of the body, including the skin. The molecular etiology has not yet been clarified for all diabetic skin conditions. Thus, this study aimed to investigate the changes of diabetes in skin compared to non-diabetic skin in rats. Fifteen days after establishing the diabetic status, skin samples from the dorsum-cervical region were harvested for subsequent analysis of alterations caused by diabetes. Our results demonstrate that diabetes stimulated higher inflammation and oxidative stress in skin, but antioxidant defense levels were lower compared to the non-diabetic group (p < 0.05). This could have been related to a decreased number of blood vessels and low expression of VEGF, eNOS and TGF-β1. Finally, insulin signaling proteins IRS, Akt, Shc and ERK showed a low expression in the diabetic group. Thus, our study shows that the pathology of diabetes induced immunohistopathological and biochemical skin changes compared to non-diabetic skin in rats. [ABSTRACT FROM AUTHOR]

Bivalve populations are controlled by several biotic and abiotic factors. Parasitism is among the biotic factors but is often neglected. In the present study, we focused on the transcriptomic and biochemical responses of Cerastoderma edule when parasitized as first intermediate host by the trematode Bucephalus minimus (sporocyst, the most damaging stage), and taking into account seasonal patterns. In order to test the hypothesis that the presence of B. minimus compromises cockle regular gene expression and biochemical performance and increases their vulnerability to other parasite species infection, cockles were sampled every other month during one year in Arcachon Bay (French Atlantic coast). Overall, results showed that B. minimus induced its first intermediate host defence mechanism against oxidative stress (mainly at gene level), increased host metabolism and energy demand especially in summer (revealed at both gene and biochemical level, although without significant differences) and was accompanied by a higher metacercariae abundance. Results allowed to accept the posted hypothesis and to conclude that transcriptomic and biochemical markers can provide additional and ecologically relevant information about parasite effects on their hosts, reflecting the invasion effects of pathogens but also the environmental conditions that animals experience. [ABSTRACT FROM AUTHOR]

The homogenization of B 0 conditions is necessary for every magnetic resonance spectroscopy (MRS) investigation. Its direct consequence is narrow spectral lines, on which reliable separation and quantification of biochemicals, and thus experimentally obtainable metabolic information, fundamentally relies. Besides spectral linewidth, unwanted B 0 inhomogeneity also impairs other aspects of the MRS experiment, such as water suppression and editing efficiency, that rely on exact frequency definition. Therefore, experimental B 0 homogenization, called B 0 shimming, is mandatory for meaningful MRS, and high-level B 0 shimming is arguably one of the most important ingredients for successful MRS investigations. In this review, we describe the relevance of B 0 homogeneity for in vivo MRS and summarize common concepts and specific solutions for its experimental optimization. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) are one of the most important carbon Nanomaterials (NMs). The production and use of these carbon NMs is increasing rapidly and, therefore, the need to assess their presence in the environment and associated risks has become increasingly important. However, limited literature is available regarding the impacts induced in aquatic organisms by this pollutant, namely in invertebrate species. Diopatra neapolitana and Hediste diversicolor are keystone polychaete species inhabiting estuaries and shallow water bodies intertidal mudflats, frequently used to evaluate the impact of environmental disturbances in these systems. To our knowledge, no information is available on physiological and biochemical alterations on these two species due to MWCNTs exposure. Thus, the present study aimed to assess the toxic effects of different MWCNTs concentrations (0.01; 0.10 and 1.00 mg/L) in both species physiological (regenerative capacity and respiration rate) and biochemical (energy reserves, metabolic activities, oxidative stress related biomarkers and neurotoxicity markers) performance, after 28 days of exposure. The results obtained revealed that exposure to MWCNTs induced negative effects on the regenerative capacity of D. neapolitana . Additionally, higher MWCNTs concentrations induced increased respiration rates in D. neapolitana. MWCNTs altered energy-related responses, with higher values of electron transport system activity, glycogen and protein concentrations in both polychaetes exposed to this contaminant. Furthermore, when exposed to MWCNTs both species showed oxidative stress with higher lipid peroxidation, lower ratio between reduced and oxidized glutathione, and higher activity of antioxidant (catalase and superoxide dismutase) and biotransformation (glutathione-S-transferases) enzymes in exposed organisms. [ABSTRACT FROM AUTHOR]

The silicon (Si) reduced tan spot ( Pyrenophora tritici-repentis ) severity up to 40%, through both biochemical defense mechanisms and histo-cytological defense responses. The activities of enzymes involved in plant defense system such as superoxide dismutase, peroxidase and chitinase showed greater activity in inoculated plants supplied with Si. Histo-cytological analysis indicated that Si potentiated the accumulation of hydrogen peroxide in the beginning of infection process. Together, these defense mechanisms resulted in the reduction of cell death at the infection sites in plants supplied with Si, which in turn showed lower disease severity. Si appears to be a promising alternative control measure for use in integrated management of tan spot. [ABSTRACT FROM AUTHOR]

DJ-1/PARK7 mutations or deletions cause autosomal recessive early onset Parkinson's disease (PD). Thus, DJ-1 protein has been extensively studied in brain and neurons. PD patients display visual symptoms; however, the visual symptoms specifically attributed to PD patients carrying DJ-1/PARK7 mutations are not known. In this study, we analyzed the structure and physiology of retinas of 3- and 6-month-old DJ-1 knockout (KO) mice to determine how loss of function of DJ-1 specifically contributes to the phenotypes observed in PD patients. As compared to controls, the DJ-1 KO mice displayed an increase in the amplitude of the scotopic ERG b-wave and cone ERG, while the amplitude of a subset of the dc-ERG components was decreased. The main structural changes in the DJ-1 KO retinas were found in the outer plexiform layer (OPL), photoreceptors and retinal pigment epithelium (RPE), which were observed at 3 months and progressively increased at 6 months. RPE thinning and structural changes within the OPL were observed in the retinas in DJ-1 KO mice. DJ-1 KO retinas also exhibited disorganized outer segments, central decrease in red/green cone opsin staining, decreased labeling of ezrin, broader distribution of ribeye labeling, decreased tyrosine hydroxylase in dopaminergic neurons, and increased 7,8-dihydro-8-oxoguanine-labeled DNA oxidation. Accelerated outer retinal atrophy was observed in DJ-1 KO mice after selective oxidative damage induced by a single tail vein injection of NaIO 3, exposing increased susceptibility to oxidative stress. Our data indicate that DJ-1-deficient retinas exhibit signs of morphological abnormalities and physiological dysfunction in association with increased oxidative stress. Degeneration of RPE cells in association with oxidative stress is a key hallmark of age-related macular degeneration (AMD). Therefore, in addition to detailing the visual defects that occur as a result of the absence of DJ-1, our data is also relevant to AMD pathogenesis. [ABSTRACT FROM AUTHOR]

Glutaredoxin (Grx), a major redox regulator, can act as a reductant of methionine sulfoxide reductase A (MsrA). However, the biochemical mechanisms involved in MsrA activity regeneration by Grx remain largely unknown. In this study, we investigated the regeneration mechanism of 1-Cys type Clostridium oremlandii MsrA (cMsrA) lacking a resolving Cys residue in a Grx-dependent assay. Kinetic analysis showed that cMsrA could be reduced by both monothiol and dithiol Grxs as efficiently as by in vitro reductant dithiothreitol. Our data revealed that the catalytic Cys sulfenic acid intermediate is not glutathionylated in the presence of the substrate, and that Grx instead directly formed a complex with cMsrA. Mass spectrometry analysis identified a disulfide bond between the N-terminal catalytic Cys of the active site of Grx and the catalytic Cys of cMsrA. This mixed disulfide bond could be resolved by glutathione. Based on these findings, we propose a model for regeneration of 1-Cys type cMsrA by Grx that involves no glutathionylation on the catalytic Cys of cMsrA. This mechanism contrasts with that of the previously known 1-Cys type MsrB. [ABSTRACT FROM AUTHOR]

Highlights: [•] Drought stress caused a significant increase in the expression of HATs. [•] The acetylation levels on histone H3 and H4 increased under drought stress as well. [•] HATs in rice are involved in drought stress responses in rice. [Copyright &y& Elsevier]

Abstract: The nature and role of intermediates have been the subject of much heated debate in the field of protein folding. Historically, intermediates were viewed as essential stepping-stones that guide a protein through the folding process to the native state. However, with the experimental identification of numerous small proteins that fold rapidly without intermediates, and the emergence from computational studies of new conceptual frameworks, came the thinking that intermediates can act as energy sinks, kinetic traps that result in less efficient folding. Whether ‘good’ or ‘bad’, it is without doubt that folding intermediates provide valuable information to protein chemists: at equilibrium they help to delineate the subdomain architecture of a protein and the hierarchy of subdomain stabilities; under kinetic conditions they provide experimentalists with additional snapshots of the folding reaction and, thereby, fundamental mechanistic details that are often lacking in the case of two-state folders. Intermediates give us valuable insights into the fluctuations from the native structure that may be important in regulating biological function. Lastly, intermediates are often the critical species in misfolding processes that lead to aggregation and disease. Here we review what we have learnt after almost half a century of protein-folding research, and we question two fundamental tests of our understanding: do we know enough about how proteins fold to design folding mechanisms de novo and can we exploit our knowledge to modulate protein-folding mechanisms in the cell for therapeutic benefit? [Copyright &y& Elsevier]

Abstract: This review briefly summarizes recent empirical research on touch. The research includes the role of touch in early development, touch deprivation, touch aversion, emotions that can be conveyed by touch, the importance of touch for interpersonal relationships and how friendly touch affects compliance in different situations. MRI data are reviewed showing activation of the orbitofrontal cortex and the caudate cortex during affective touch. Physiological and biochemical effects of touch are also reviewed including decreased heart rate, blood pressure and cortisol and increased oxytocin. Similar changes noted following moderate pressure massage appear to be mediated by the stimulation of pressure receptors and increased vagal activity. Increased serotonin and decreased substance P may explain its pain-alleviating effects. Positive shifts in frontal EEG also accompany moderate pressure massage along with increased attentiveness, decreased depression and enhanced immune function including increased natural killer cells, making massage therapy one of the most effective forms of touch. [Copyright &y& Elsevier]

Advances in our understanding of the physiology and metabolism of Northern krill, Meganyctiphanes norvegica have been sporadic but significant. Despite problems with keeping M. norvegica in good condition in the laboratory, those who have tried, and succeeded, have contributed to a better knowledge of krill biology and challenged our understanding of some basic biological processes. Most recent work has been concentrated in the fields of digestive physiology, lipid biochemistry, respiration and anaerobiosis, metabolic properties, and pollutants. M. norvegica is capable of digesting an opportunistic, omnivorous diet, showing some digestive enzyme polymorphism and high levels of enzyme activity, the latter varying with season. It also seems capable of digesting cellulose and hemicelluloses, for example, laminarin. The biochemical composition of krill is relatively well known with some recent extensive work focusing on the previously little studied lipid and fatty acid composition, particularly with reference to reproduction, overwintering energy storage and as a nutrition marker. A high aerobic metabolism (but poor anaerobic capacity) is characteristic of M. norvegica, and how this is affected by temperature, low O2, and season has attracted some attention, particularly in the context of diel vertical migration (DVM) across pronounced pycnoclines. Despite determining high metabolic turnover rates and a high physiological plasticity for this species, we know little of the regulative potential of metabolites, particularly their modulative effect on enzyme activity. Certainly a modest ability to maintain aerobic metabolism when encountering hypoxia, and little or no ability to osmoregulate in hyposaline conditions, does not prevent DVM in adults of this species. The ability to maintain aerobic metabolism develops early in ontogeny at about furcilia III (i.e. concurrent with first DVM behaviour). The respiratory pigment of M. norvegica, haemocyanin, has a low O2 affinity and high temperature sensitivity (although temperature has the opposite effect on O2 binding than found for nearly every other haemocyanin). Also surprising is the apparent use of haemocyanin as an energy source/store. While recent work has focused on physiological effects, the ecophysiological effects of transuric elements and trace metals, the effects of pollution generally are widely understudied. [ABSTRACT FROM AUTHOR]

Abstract: Rett syndrome (RTT) is a rare X-linked autistic-spectrum neurological disorder associated with impaired energy metabolism, seizure susceptibility, progressive social behavioral regression, and motor impairment primarily in young girls. The objective of this study was to examine the influence of restricted diets, including a ketogenic diet (KD) and a standard rodent chow diet (SD), on behavior in male Mecp2 308/y mice, a model of RTT. The KD is a high-fat, low-carbohydrate diet that has anticonvulsant efficacy in children with intractable epilepsy and may be therapeutic in children with RTT. Following an 11-day pretrial period, adult wild-type and mutant Rett mice were separated into groups that were fed either an SD in unrestricted or restricted amounts or a ketogenic diet (KetoCal) in restricted amounts for a total of 30 days. The restricted diets were administered to reduce mouse body weight by 20–23% compared to the body weight of each mouse before the initiation of the diet. All mice were subjected to a battery of behavioral tests to determine the influence of the diet on the RTT phenotype. We found that performance in tests of motor behavior and anxiety was significantly worse in male RTT mice compared to wild-type mice and that restriction of either the KD or the SD improved motor behavior and reduced anxiety. We conclude that although both restricted diets increased the tendency of Rett mice to explore a novel environment, the beneficial effects of the KD were due more to calorie restriction than to the composition of the diet. Our findings suggest that calorically restricted diets could be effective in reducing the anxiety and in improving motor behavior in girls with RTT. [Copyright &y& Elsevier]

Abstract: In fungi, the velvet gene, or veA, is involved in the regulation of diverse cellular processes, including control of asexual and sexual development as well as secondary metabolism. This global regulator is conserved in numerous fungal species. Interestingly, in Aspergilli, where most of the studies on veA have been carried out, this gene has been described to mediate development in response to light. In recent years the knowledge of this important regulatory system has expanded through the use of Aspergillus nidulans as a model organism, and through the study of veA orthologs across fungal genera. This review includes information on the current understanding of veA function and its mechanism of action. The fact that veA has only been found in fungi, together with advances in the elucidation of the veA mechanism, might be useful in designing future control strategies to decrease the detrimental effects of fungi while enhancing those qualities that are beneficial. [Copyright &y& Elsevier]

Abstract: The posterior cingulate cortex (PCC) is the brain region displaying the earliest sign of energy hypometabolism in patients with amnestic mild cognitive impairment (MCI) who develop Alzheimer’s disease (AD). In particular, the activity of the mitochondrial respiratory enzyme cytochrome oxidase (C.O.) is selectively inhibited within the PCC in AD. The present study is the first experimental analysis designed to model in animals the localized cortical C.O. inhibition found as the earliest metabolic sign of early-stage AD in human neuroimaging studies. Rats were used to model local inhibition of C.O. by direct injection of the C.O. inhibitor sodium azide into the PCC. Learning and memory were examined in a spatial holeboard task and brains were analyzed using quantitative histochemical, morphological and biochemical techniques. Behavioral results showed that sodium azide-treated rats were impaired in their memory of the baited pattern in probe trials as compared to their training scores before treatment, without non-specific behavioral differences. Brain analyses showed that C.O. inhibition was specific to the PCC, and sodium azide increased lipid peroxidation, gliosis and neuron loss, and lead to a network functional disconnection between the PCC and interconnected hippocampal regions. It was concluded that impaired memory by local C.O. inhibition in the PCC may serve to model in animals a metabolic lesion similar to that found in patients with amnestic MCI and early-stage AD. This model may be useful as an in vivo testing platform to investigate neuroprotective strategies to prevent or reduce the amnestic effects produced by posterior cingulate energy hypometabolism. [Copyright &y& Elsevier]

Abstract: Previously, we identified a clathrin-dependent slow endocytosis and a clathrin-independent fast endocytosis in pancreatic β cells, both triggered by elevated cytoplasmic Ca2+ concentration. In the current study, we attempted to explore the roles of different dynamin isoforms in these endocytotic processes. We first confirmed the existence of both neuron-specific dynamin 1 and ubiquitous dynamin 2 in INS-1 cells using both quantitative RT-PCR and Western blot experiments. By specifically knocking down the endogenous level of either dynamin isoform from INS-1 cells, we showed that dynamin 1 and dynamin 2 simultaneously participate in the clathrin-independent and -dependent membrane retrieval in pancreatic β cells. Transferrin internalization was also inhibited in cells with knock down of both dynamin 1 and dynamin 2. Based on these results, we argue that different dynamin isoforms play overlapping roles in different types of endocytosis. [Copyright &y& Elsevier]

Abstract: In addition to neuronal loss in the cerebellum and basal ganglia, recent imaging studies have suggested that cortical involvement may be more extensive in patients with MSA. In this study, we focused on cortical metabolic patterns in 41 patients with MSA-C and 30 controls, using statistical parametric mapping analysis to evaluate whether metabolic derangement in MSA-C patients involved the cortical area and correlated cerebral metabolism with clinical parameters. In patients with MSA-C, SPM analysis revealed that, apart from the expected reduction of FDG-uptake in brainstem–cerebellar area, there was a significant hypometabolism in widespread frontal cortex, including inferior orbitofrontal, rectus, middle and superior frontal, and superior mesiofrontal extending to cingulum, and left inferior parietal cortex. In a subgroup analysis of MSA-C patients, metabolic derangement in the cerebral cortex was visible even in the early stages of MSA-C. In advanced stages, the metabolic derangement tended to evolve into the rostral brainstem and into other cortical areas, including left inferior frontal cortex and right inferior orbitofrontal, right anterior and middle cingulate, and anterior portion of superior mesiofrontal gyri. In correlation analysis, reduced FDG-uptake in orbitofrontal area was most significantly correlated with disease severity and duration, followed by the medial frontal, the dorsal portion of the midbrain, and the cerebellum. Our study demonstrated that there were widespread areas of decreased metabolism in the cerebral cortex and, as the disease progressed, the pattern of metabolic derangement tended to evolve into other frontal areas without significant changes in cerebellar metabolism, suggesting that reduced FDG-uptake in cortical area may be associated with the primary disease process. [Copyright &y& Elsevier]

Abstract: Trabectedin is a promising anticancer agent, but dose-limiting hepatotoxicity was observed during phase I/II clinical trials. Dexamethasone (DEX) has been shown to significantly reduce trabectedin-mediated hepatotoxicity. The current study was designed to assess the capability of sandwich-cultured primary rat hepatocytes (SCRH) to predict the hepato-protective effect of DEX against trabectedin-mediated cytotoxicity. The role of multidrug resistance-associated protein 2 (Mrp2; Abcc2) in trabectedin hepatic disposition also was examined. In SCRH from wild-type Wistar rats, cytotoxicity was observed after 24-h continuous exposure to trabectedin. SCRH pretreated with additional DEX (1 μM) exhibited a 2- to 3-fold decrease in toxicity at 100 nM and 1000 nM trabectedin. Unexpectedly, toxicity in SCRH from Mrp2-deficient (TR−) compared to wild-type Wistar rats was markedly reduced. Depletion of glutathione from SCRH using buthionine sulfoximine (BSO) mitigated trabectedin toxicity associated with 100 nM and 1000 nM trabectedin. Western blot analysis demonstrated increased levels of CYP3A1/2 and Mrp2 in SCRH pretreated with DEX; interestingly, Mrp4 expression was increased in SCRH after BSO exposure. Trabectedin biliary recovery in isolated perfused livers from TR− rats was decreased by ∼75% compared to wild-type livers. In conclusion, SCRH represent a useful in vitro model to predict the hepatotoxicity of trabectedin observed in vivo. The protection by DEX against trabectedin-mediated cytotoxicity may be attributed, in part, to enhanced Mrp2 biliary excretion and increased metabolism by CYP3A1/2. Decreased trabectedin toxicity in SCRH from TR− rats, and in SCRH pretreated with BSO, may be due to increased basolateral excretion of trabectedin by Mrp3 and/or Mrp4. [Copyright &y& Elsevier]

Abstract: Nitrogen signalling in cyanobacteria involves a complex network in which the availability of iron plays an important role. In the nitrogen-fixing cyanobacterium Anabaena sp. PCC 7120, iron uptake is controlled by FurA, while NtcA is the master regulator of nitrogen metabolism and shows a mutual dependence with HetR in the first steps of heterocyst development. Expression of FurA is modulated by NtcA and it is enhanced in a hetR − background. Iron starvation in cells grown in the presence of combined nitrogen causes a moderate increase in the transcription of glnA that is more evident in a ntcA − background. Those results evidence a tight link between the reserves of iron and nitrogen metabolism that leads us to search for target genes potentially co-regulated by FurA and NtcA. Using a bioinformatic approach we have found a significant number of NtcA-regulated genes exhibiting iron boxes in their upstream regions. Our computational predictions have been validated using electrophoretic mobility shift assay (EMSA) analysis. These candidates for dual regulation are involved in different functions such as photosynthesis (i.e. psaL, petH, rbcL, isiA), heterocyst differentiation (i.e. xisA, hanA, prpJ, nifH), transcriptional regulation (several alternative sigma factors) or redox balance (i.e. trxA, ftrC, gor). The identification of common elements overlapping the NtcA and FurA regulons allows us to establish a previously unrecognized transcriptional regulatory connection between iron homeostasis, redox control and nitrogen metabolism. [Copyright &y& Elsevier]

Abstract: Leigh’s syndrome is a complex neurological disease with little known correlation between causes and symptoms. Mutations in pyruvate dehydrogenase and electron transport chain complexes have been associated with this syndrome, although the identification of affected enzymes is difficult, if not impossible, with non-invasive clinical tests. In this study, isotopomer analysis is used to characterize the metabolic phenotype of normal and Leigh’s syndrome fibroblasts (GM01503), thereby identifying affected enzymes in the diseased cells. Fibroblasts are grown with DMEM media enriched with 13C labeled glucose. Amino acids from media and proteins as well as lactate are analyzed with GC–MS to identify their label distributions. A computational model accounting for all major pathways in fibroblast metabolism (including 430 metabolites and 508 reactions) is built to determine the metabolic steady states of the normal and Leigh’s cell lines based on measured substrate uptake and secretion rates and isotopomer data. Results show that (i) Leigh’s syndrome affected cells have slower metabolism than control fibroblasts as evidenced by their overall slower substrate utilization and lower secretion of end products; (ii) intracellular fluxes predicted by the models, some of which are validated by biochemical studies published in the literature, show that the respiratory chain in Leigh’s affected cells can produce ATP at a similar rate as the controls, but with a more restricted flux range; and (iii) mutations causing the defects observed in the Leigh’s cells are likely to be in succinate cytochrome c reductase. [Copyright &y& Elsevier]

Abstract: Cellular life requires the presence of a set of biochemical mechanisms in order to maintain a predictable process of growth and division. Several attempts have been made towards the building of minimal protocells from a top-down approach, i.e. by using available biomolecules. This type of synthetic approach has so far been only partially successful, and appropriate models of the synthetic protocell cycle might be needed to guide future experiments. In this paper, we present a simple biochemically and physically feasible model of cell replication involving a discrete semi-permeable vesicle with an internal minimal metabolism involving two reactive centers. It is shown that such a system can effectively undergo a whole cell replication cycle. The model can be used as a basic framework to model whole protocell dynamics including more complex sets of reactions. The possible implementation of our design in future synthetic protocells is outlined. [Copyright &y& Elsevier]

Abstract: Elevated levels of circulating corticosterone commonly occur in response to stressors in wild vertebrates. A rise in corticosterone, usually in animals of subordinate rank, results in a variety of effects on behavior and physiology. Behavioral and physiological responses to short-term increases in corticosterone are well studied. In contrast, the effects of chronic elevated levels of corticosterone are poorly understood, particularly in lizards. Here, we examined the long-term effects of exogenous corticosterone on locomotor performance, resting and active metabolic rate, and hematocrit in male side-blotched lizards Uta stansburiana. Corticosterone implantation resulted in higher levels of stamina relative to sham-surgery controls. In addition, lizards with elevated corticosterone exhibited lower resting metabolic rates relative to controls. Corticosterone had no effect on peak activity metabolism but did result in faster recovery times following exhaustive exercise. We suggest that elevated levels of corticosterone in response to dominance interactions promote enhanced locomotor abilities, perhaps as a flight response to avoid agonistic interactions. Furthermore, stressed lizards are characterized by lower resting metabolic rates, which may serve as strategy to conserve energy stores and enhance survival. [Copyright &y& Elsevier]

Abstract: In addition to effects on metabolism and appetite, leptin is a reproductive hormone produced and secreted by the placenta of many, but not all mammalian species. In mice, in which the placenta does not secrete leptin, exogenously added leptin stimulates invasiveness of early (but not late)-gestation trophoblast cells. We report a similar phenomenon occurs in Myotis lucifugus (little brown myotis), a species in which the placenta synthesizes and secretes leptin. Immunoneutralization of endogenously secreted leptin from cultured M. lucifugus trophoblast cells inhibited the ability of these cells to invade a matrigel matrix. The effect was not due to an inhibitory effect of the antibody on cell proliferation, nor was it a non-specific effect of antibody administration. Cell invasion was significantly reduced in untreated cells obtained from late-gestation placentas, and the antibody had no effect at that time. This occurred despite continued expression throughout gestation of the long (OBRb) and short (OBRa) isoforms of leptin receptor mRNA. This study suggests that an important function of leptin during pregnancy is an effect on trophoblast cell invasiveness, at a time when the placenta is becoming established. That this occurs in two phylogenetically unrelated and distant species, regardless of whether the placenta is a source of secreted leptin, suggests that this is a highly conserved reproductive action of leptin. [Copyright &y& Elsevier]

Abstract: Most of the adenosine triphosphate (ATP) synthesized during glucose metabolism is produced in the mitochondria through oxidative phosphorylation. This is a complex reaction powered by the proton gradient across the mitochondrial inner membrane, which is generated by mitochondrial respiration. A detailed model of this reaction, which includes dynamic equations for the key mitochondrial variables, was developed earlier by Magnus and Keizer. However, this model is extraordinarily complicated. We develop a simpler model that captures the behavior of the original model but is easier to use and to understand. We then use it to investigate the mitochondrial responses to glycolytic and calcium input. We use the model to explain experimental observations of the opposite effects of raising cytosolic in low and high glucose, and to predict the effects of a mutation in the mitochondrial enzyme nicotinamide nucleotide transhydrogenase (Nnt) in pancreatic -cells. [Copyright &y& Elsevier]

Abstract: Mitochondrial acetoacetyl-CoA thiolase (T2) deficiency is a rare inherited metabolic disorder affecting isoleucine catabolism and ketone body metabolism. So far, more than 39 different mutations have been identified in 60 T2-deficient patients. However, no large deletions have been reported. We herein report the first case of a large T2 gene deletion from intron 1 to intron 4 in a T2-deficient patient (GK41). cDNA analysis revealed that an aberrant cDNA with exons 2–5 skipping was a major transcript, associated with a minor transcript of exons 2–4 skipping with a 94-bp insertion composed of an intron 1 sequence. Genomic analysis indicated an absence of PCR amplification of exons 2–4 and gene deletion was revealed by Southern blot analysis. Cloning and sequencing long range PCR products revealed a 6.4kb deletion. Alu element-mediated unequal homologous recombination between an Alu-Sx in intron 1 and another Alu-Y in intron 4 appears to be responsible for this deletion. [Copyright &y& Elsevier]

Abstract: For decades, demands associated with the predictable life-history cycle have been considered stressful and have not been distinguished from stress that occurs in association with unpredictable and life-threatening perturbations in the environment. The recent emergence of the concept of allostasis distinguishes behavioral and physiological responses to predictable routines as opposed to unpredictable perturbations, and allows for their comparison within one theoretical framework. Glucocorticosteroids (GCs) have been proposed as important mediators of allostasis, as they allow for rapid readjustment and support of behavior and physiology in response to predictable and unpredictable demands (allostatic load). Much work has already been done in defining GC action at the high concentrations that accompany life-threatening perturbations. However, less is known about the role of GCs in relation to daily and seasonal life processes. In this review, we summarize the known behavioral and physiological effects of GCs relating to the predictable life-history cycle, paying particular attention to feeding behavior, locomotor activity and energy metabolism. Although we utilize a comparative approach, emphasis is placed on birds. In addition, we briefly review effects of GCs at stress-related concentrations to test the hypothesis that different levels of GCs play specific and distinct roles in the regulation of life processes and, thus, participate in the promotion of different physiological states. We also examine the receptor types through which GC action may be mediated and suggest mechanisms whereby different GC concentrations may exert their actions. In conclusion, we argue that biological actions of GCs at “non-stress” seasonal concentrations play a critical role in the adjustment of responses that accompany predictable variability in the environment and demand more careful consideration in future studies. [Copyright &y& Elsevier]

Abstract: We have previously shown that the proteasome activator PA28 is essential to Hsp90-dependent protein refolding in vitro, where PA28 mediates transfer of the Hsp90-bound substrate protein to the Hsc70/Hsp40 chaperone machine for its correct refolding. This observation suggests that PA28 may also collaborate with Hsp90 in cells. To examine this possibility, here we have used double-stranded RNA interference (RNAi) against PA28 in Caenorhabditis elegans mutants of daf-21, which encodes Hsp90. We show that C. elegans PA28 facilitates Hsp90-initiated protein refolding, albeit with an activity lower than that of mouse PA28 proteins. RNAi-mediated knockdown of PA28 significantly suppresses the Daf-c (dauer formation constitutive) phenotype of the daf-21 mutant, but it has no affect on the distinct defects of this mutant in sensing odorants. Taking these results together, we conclude that PA28 is likely to function in collaboration with Hsp90 in vivo. [Copyright &y& Elsevier]

Abstract: Xenotransplantation is one of the most attractive solutions for the current worldwide shortage of organs. The knocking out of α1,3-galactosyltransferase in pigs resulted in a drastic reduction in xenoantigenicity. However, more recent studies indicate that other xeno-antigens, so-called non-Gal antigens, will also need to be downregulated. In this study, pig N-acetylglucosaminyltransferase I (GnT-I), a key enzyme that initiates the biosynthesis of hybrid- and complex-type N-linked sugar chains, was isolated and the pigGnT-I.2 specific for the O-linked sugar chain was also isolated. Point mutants, pigGnT-I(123) and pigGnT-I(320), were subsequently constructed. While pigGnT-I(123) shows an indistinct dominant negative effect for endogenous GnT-I in pig cells, pigGnT-I(320) had a drastic effect. In addition, in the case of pig cell transfectants with pigGnT-I(320), cell surface carbohydrate structures were significantly altered and its antigenicity to human serum was reduced. Consequently, pigGnT-I(320) appears to be potentially useful in xenotransplantation by remodeling the carbohydrate structures on pig cells. [Copyright &y& Elsevier]

Abstract: Osteoclasts are multinucleated cells responsible for bone resorption and play important roles in normal skeletal development, in the maintenance of its integrity throughout life, and in calcium metabolism. During bone resorption, the cytoskeleton of osteoclasts undergoes extensive reorganization, with polarization and formation of ruffled borders to secrete acid and formation of sealing zone to prevent leakage. The differentiation and function of osteoclasts are in turn regulated by osteoblasts, stromal cells, and bone. They are also subjected to negative feedback regulation by extracellular and intracellular calcium concentrations. [Copyright &y& Elsevier]

Abstract: Burkitt’s lymphoma is an aggressive B-cell neoplasm resulting from deregulated c-myc expression. We have previously shown that proliferation of Burkitt’s lymphoma cell lines such as Ramos is markedly reduced by iron treatment. It has been shown that iron induces expression of c-myc which, owing to its transcriptional regulatory functions, regulates genes involved in iron metabolism. Transient enhancement of c-myc expression by iron could increase the expression of genes involved in iron incorporation, which could lead to an accumulation of intracellular free iron. Here, we have investigated whether cells with a high basal level of c-Myc were more likely to accumulate free iron. Our results suggest that the basal level of c-Myc in Ramos cells is twofold higher than what is seen in HL-60 cells. Moreover, in Ramos cells, where c-Myc is expressed at a high level, H-ferritin expression is down-regulated, transferrin receptor (CD71) expression is increased, and ferritin translation is inhibited. These modifications in iron metabolism, resulting from the strong basal expression of c-Myc, and amplified by iron addition, could lead to a disruption in homeostasis and consequently to growth arrest. [Copyright &y& Elsevier]

Abstract: Our research aims to provide quantitatively transparent, biologically realistic descriptions of the processes involved in hemostasis which will permit predictions of the behavior of the coagulation system in normal and pathologic states. We use four models of coagulation: (1) numerical approximations of the tissue factor (Tf) pathway of thrombin generation based upon mechanism and dynamics; (2) Tf activation of the “blood coagulation proteome” from isolated cells and proteins; (3) Tf activated contact pathway inhibited whole blood in vitro; and (4) blood shed from standardized microvascular wounds in vivo. The results from these models are integrated in interactive assessments aimed at achieving convergence of biochemical rigor and biological authenticity. Microvascular injury is the most biologically secure but least accessible to mechanistic study. Numerical models while quantitatively transparent are biologically limited. By the integrated analyses of all four models, we establish observations which require inclusion or discovery of new parameters to achieve mechanistically interpretable biological reality. Discoveries made in this fashion have included thrombin''s role in the initiation phase, TFPI/ATIII/APC synergy interactions, rfVIIa in fVII deficiency, the roles of fVIII and fIX in the Tf reaction, and the cleavage of fIX by fXa membrane. Ideally, our results will provide descriptions which predict the behavior of the biological blood coagulation system under normal and pathologic conditions. [Copyright &y& Elsevier]

Abstract: Cystic fibrosis (CF), an autosomal recessive disorder, is caused by the disruption of biosynthesis or the function of a membrane cAMP-activated chloride channel, CFTR. CFTR regulatory mechanisms include recruitment of channel proteins to the cell surface from intracellular pools and by protein–protein interactions. Rab proteins are small GTPases involved in regulated trafficking controlling vesicle docking and fusion. Rab4 controls recycling events from endosome to the plasma membrane, fusion, and degradation. The colorectal cell line HT-29 natively expresses CFTR and responds to cAMP stimulation with an increase in CFTR-mediated currents. Rab4 over-expression in HT-29 cells inhibits both basal and cAMP-stimulated CFTR-mediated currents. GTPase-deficient Rab4Q67L and GDP locked Rab4S22N both inhibit channel activity, which appears characteristically different. Active status of Rab4 was confirmed by GTP overlay assay, while its expression was verified by Western blotting. The pull-down and immunoprecipitation experiments suggest that Rab4 physically interacts with CFTR through protein–protein interaction. Biotinylation with cell impermeant NHS-Sulfo-SS-Biotin implies that Rab4 impairs CFTR expression at cell surface. The enhanced cytosolic CFTR indicates that Rab4 expression restrains CFTR appearance at the cell membrane. The study suggests that Rab4 regulates the channel through multiple mechanisms that include protein-protein interaction, GTP/GDP exchange, and channel protein trafficking. We propose that Rab4 is a dynamic molecule with a significant role in CFTR function. [Copyright &y& Elsevier]

Abstract: Calnexin is an endoplasmic reticulum (ER) resident type I integral membrane phosphoprotein. This protein is actively involved in the ER glycoprotein quality control through its luminal domain. In addition, although calnexin also interacts with membrane-bound ribosomes, the nature of this interaction remains poorly characterized. Herein, using in vitro approaches, we demonstrate that calnexin cytosolic domain directly interacts with, at least 5 ribosomal proteins. Furthermore, we characterize more specifically its interaction with the ribosomal protein L4 and that L4 binds to the 19 carboxy terminal amino acids of calnexin. We suggest that the direct interaction of calnexin with membrane-bound ribosomes may represent a regulatory mechanism for its lectin-like chaperone function. [Copyright &y& Elsevier]

Abstract: Indoleamine 2,3-dioxygenase (EC 1.13.11.42) is a heme-containing dioxygenase which catalyzes the first and rate-limiting step in the major pathway of l-tryptophan catabolism in mammals. Much attention has recently been focused on the dioxygenase because this metabolic pathway is involved not only in a variety of physiological functions but also in many diseases. In this review, the discovery and unique catalytic properties of dioxygenase are described first, and then the recent findings regarding the dioxygenase-initiated tryptophan metabolism are summarized, with special emphasis on the detrimental role of dioxygenase in side effects of interferon-γ and interleukin-12 (by systemic tryptophan depletion), the escape of malignant tumors from immune surveillance (by immunosuppression caused by tryptophan depletion), several neurodegenerative disorders including Alzheimer’s disease (by an aberrant production of neurotoxin, quinolinic acid), and age-related cataract (due to “Kynurenilation,” a novel post-translational modification of lens proteins with tryptophan-derived UV filters). [Copyright &y& Elsevier]

Abstract: Using a number of different homeostatic control mechanisms in the brain and peripheral physiological systems, metabolic activity is continuously regulated at rest and during exercise to prevent catastrophic system failure. Essential for the function of these regulatory processes are baseline “setpoint” levels of metabolic function, which can be used to calculate the level of response required for the maintenance of system homeostasis after system perturbation, and to which the perturbed metabolic activity levels are returned to at the end of the regulatory process. How these setpoint levels of all the different metabolic variables in the different peripheral physiological systems are created and maintained, and why they are similar in different individuals, has not been well explained. In this article, putative system regulators of metabolic setpoint levels are described. These include that: (i) innate setpoint values are stored in a certain region of the central nervous system, such as the hypothalamus; (ii) setpoint values are created and maintained as a response to continuous external perturbations, such as gravity or “zeitgebers”, (iii) setpoint values are created and maintained by complex system dynamical activity in the different peripheral systems, where setpoint levels are regulated by the ongoing feedback control activity between different peripheral variables; (iv) human anatomical and biomechanical constraints contribute to the creation and maintenance of metabolic setpoints values; or (v) a combination of all these four different mechanisms occurs. Exercise training and disease processes can affect these metabolic setpoint values, but the setpoint values are returned to pre-training or pre-disease levels if the training stimulus is removed or if the disease process is cured. Further work is required to determine what the ultimate system regulator of metabolic setpoint values is, why some setpoint values are more stringently protected by homeostatic regulatory mechanisms than others, and the role of conscious decision making processes in determining the regulation of metabolic setpoint values. [Copyright &y& Elsevier]

Spermine oxidase (SMO) is a recently described flavoenzyme belonging to the class of polyamine oxidases (PAOs) and participating in the polyamine metabolism in animal cells. In this paper we describe the expression, purification, and characterization of the catalytic properties of a recombinant mouse SMO (mSMO). The purified enzyme has absorbance peaks at 457nm (ε=11mM−1cm−1) and 378nm, shows a molecular mass of ∼63kDa, and has Km and kcat values of 170μM and 4.8s−1, using spermine as substrate; it is unable to oxidize other free or acetylated polyamines. The mechanism-based PAO inhibitor N,N1-bis(2,3-butadienyl)-1,4-butanediamine (MDL72,527) acts as a competitive inhibitor of mSMO, with an apparent dissociation constant Ki=63μM. If incubated for longer times, MDL72,527 yields irreversible inhibition of the enzyme with a half-life of 15min at 100μM MDL72,527. The mMSO catalytic mechanism, investigated by stopped flow, is consistent with a simple four-step kinetic scheme. [Copyright &y& Elsevier]

As an ATP-dependent DNA helicase, RecG can repair DNA replication forks in many organisms. However, knowledge of recG in Bacillus thuringiensis (Bt) is limited. In our previous study, recG was found damaged in Bt LLP29-M19, which was more resistant to ultraviolet light (UV) after exposing Bt LLP29 to UV for 19 generations. To further understand the function of recG in the mechanism of Bt UV resistance, recG was knocked out and recovered with homologous recombination technology in Bt LLP29. Comparing the resistance of the different mutants to UVB, Bt ∆ recG- LLP29 lacking recG was found more sensitive to UVB, hydroxyurea (HU) and H 2 O 2 than LLP29 and the complementation strain. To compare the expression level of recG in the Bt strains under different UV treatments, Quantitative Real-time PCR (RT-qPCR) of recG was performed in the tested Bt strains, which showed that the expression level of recG in Bt ∆ recG -LLP29 was substantially lower than that in the original strain and complementation strain. Interestingly, when exposed to UV for 20 min, RecG expression in both Bt LLP29 and Bt recG -R was the highest. The unwinding activity of recG in Bt LLP29 and the complementation strain were also found higher than that of the recG knockout strain, Bt ∆ recG -LLP29. These results demonstrate that recG is involved with the resistance of Bt to UV. These findings not only enhance the understanding of the Bt UV resistance mechanism, but also provide an important theoretical basis for the application of Bt. Unlabelled Image • recG was knocked out and recovered with homologous recombination technology in Bt LLP29. • Bt ∆ recG- LLP29 lacking recG was found more sensitive to UVB, hydroxyurea (HU) and H 2 O 2 than LLP29-M19 and the complementation strain. • The expression level of recG in Bt ∆ recG -LLP29 was substantially lower than that in the original strain and complementation strain. • The unwinding and ATPase activities of recG in Bt LLP29 and the complementation strain were also found higher than that of the recG knockout strain, Bt ∆ recG -LLP29. • These results demonstrate that recG is involved with the resistance of Bt to UV. [ABSTRACT FROM AUTHOR]

Recreational, seated video gaming (gaming) has become a favorite pastime of children, adolescents, and adults (gamers) in developed countries. Some engage in gaming behavior for more than 6 h daily, which can subsequently lead to less time spent being physically active. Gaming can potentially have a serious impact on the physiology and biochemistry of gamers and can influence both short-term and long-term health. The aim of this review was to provide an overview of what is known about how gaming affects physiological and biochemical parameters in the human body and how studies have previously been designed and to discuss how studies can be designed moving forward. The literature search included material from three scientific databases (PubMed, EMBASE, and Web of Science) using a two-block search strategy. To be included in this review, studies had to investigate a biochemical or physiological aspect of sedentary, video game-related activities. Studies that investigated neurological, psychologic or musculoskeletal outcomes along with physiological or biochemical outcomes in gaming were eligible for inclusion. Studies regarding psychiatric conditions were excluded as this subject was outside the scope of this review. Additionally, non-English language articles were excluded. A total of 5417 articles were screened, 138 studies from the literature search and 4 studies from reference lists were selected for further evaluation. The studies were evaluated based on their abstracts or full texts, and 51 studies were eventually included in the review. Thirty-seven studies included physiological results, seven studies included biochemical results, and seven studies included both. Several outcomes such as heart rate, blood pressure, blood glucose levels, and cortisol levels, were the subjects of a large number of investigations. This field is heterogenic and does not lend itself to firm conclusions. Tentatively, it seems reasonable to conclude that heart rate variability studies show that gaming increases activity in the sympathetic nervous system. More high-quality studies are required, and the lack of studies using uniform, standardized designs and realistic gaming sessions (i.e., longer than 30 min) limits our current knowledge. [ABSTRACT FROM AUTHOR]

Abstract: We describe the application and evaluation of a widely available commercial jar as an anaerobic container suitable for the growth of a wide variety of anaerobes. A system for generating stable anaerobiosis was developed by combining standard anaerobic environment generators with Click-Clack jars produced by Click-Clack Ltd. (http://www.clickclack.com). This system was simple, reliable, and reduced capital outlay on anaerobic jars by at least an order of magnitude. [Copyright &y& Elsevier]

Abstract: We hypothesized that because depletion of vitamin A blocks the initiation of phototransduction, such inhibition of functional activation should lead to decrease retinal metabolism and perfusion. In a case study of a vitamin A-depleted patient, we found that retinal vessel diameters, a surrogate measure of retinal perfusion, increased in concert with the restitution of electroretinographic function following vitamin A supplementation. When normalized to conditions after treatment, the relative magnitude of study parameters at presentation were: scotopic electroretinography B-wave amplitude 1.2%, photopic electroretrinography B-wave amplitude 23%, retinal vein diameter 88%, retinal artery diameter 94%. These observations support that activation of the visual process results in increased retinal metabolism and perfusion. [Copyright &y& Elsevier]