The role of photosynthesis related pigments in light harvesting, photoprotection and enhancement of photosynthetic yield in planta.

Photosynthetic pigments are an integral and vital part of all photosynthetic machinery and are present in different types and abundances throughout the photosynthetic apparatus. Chlorophyll, carotenoids and phycobilins are the prime photosynthetic pigments which facilitate efficient light absorption in plants, algae, and cyanobacteria. The chlorophyll family plays a vital role in light harvesting by absorbing light at different wavelengths and allowing photosynthetic organisms to adapt to different environments, either in the long-term or during transient changes in light. Carotenoids play diverse roles in photosynthesis, including light capture and as crucial antioxidants to reduce photodamage and photoinhibition. In the marine habitat, phycobilins capture a wide spectrum of light and have allowed cyanobacteria and red algae to colonise deep waters where other frequencies of light are attenuated by the water column. In this review, we discuss the potential strategies that photosynthetic pigments provide, coupled with development of molecular biological techniques, to improve crop yields through enhanced light harvesting, increased photoprotection and improved photosynthetic efficiency.

Characterization of Chicken Leukocyte Subsets from Lymphatic Tissue by Flow Cytometry.

Determining the abundance of leukocyte subtypes, including lymphocyte subpopulations, not only in blood but also in lymphatic tissues, is inevitable to assess the immune status of an organism for research purposes. However, nucleated thrombocytes and erythrocytes exacerbate many hematological techniques in avian species. In order to enable a rapid discrimination of leukocyte subsets from lymphatic tissues of chicken, we adapted existing flow cytometric methods for counting leukocytes in chicken blood. We established staining and gating strategies allowing the flow cytometric characterization and enumeration of total leukocytes, thrombocytes, monocytes/macrophages, CD8α+ lymphocytes, CD4+ T cells, γδ T cells, and B cells in chicken spleen and CD8α+ lymphocytes, CD4+ T cells, γδ T cells, and B cells among intraepithelial lymphocytes in chicken cecal tonsils. For this, we prepared single-cell suspensions of spleen and isolated intraepithelial lymphocytes from cecal tonsils without density centrifugation, and performed antibody staining of cells without subsequent washing steps to prevent cell loss and falsification of obtained cell counts. © 2020 The Authors. Cytometry Part A published by Wiley Periodicals LLC on behalf of International Society for Advancement of Cytometry.

Disturbed circadian rhythm of locomotor activity of pullets is related to feather pecking in laying hens.

Various aspects of activity, such as spontaneous activity, explorative activity, activity in open-field tests, and hyperactivity syndrome have been explored as causal factors of feather pecking in laying hens, with no clear results. In all previous studies, mean values of activity over different time intervals were used as criteria. Incidental observation of alternated oviposition time in lines selected for high (HFP) and low feather pecking (LFP), supported by a recent study which showed differentially expressed genes related to the circadian clock in the same lines, led to the hypothesis that feather pecking may be related to a disturbed diurnal activity rhythm. Hence activity recordings of a previous generation of these lines have been reanalyzed. Data sets of a total of 682 pullets of 3 subsequent hatches of HFP, LFP, and an unselected control line (CONTR) were used. Locomotor activity was recorded in pullets housed in groups of mixed lines in a deep litter pen on 7 consecutive 13-h light phases, using a radio-frequency identification antenna system. The number of approaches to the antenna system was recorded as a measure of locomotor activity and analyzed using a generalized linear mixed model including hatch, line, time of day and the interactions of hatch × time of day and line × time of day as fixed effects. Significant effects were found for time and the interaction line × time of day but not for line. All lines showed a bimodal pattern of diurnal activity. The peak activity of the HFP in the morning was lower than that of the LFP and CONTR. In the afternoon peak all lines differed with the highest mean in the LFP followed by CONTR and HFP. The present results provide support for the hypothesis that a disturbed circadian clock plays a role in the development of feather pecking.

Short- and long-term consequences of stocking density during rearing on the immune system and welfare of laying hens.

Already during early life, chickens need to cope with chronic stressors that can impair their health and welfare, with stocking density being one of the most influential factors. Nevertheless, there is a gap in research on the influence of stocking density on laying hens during rearing and in the subsequent laying period. This study therefore investigated how stocking density during rearing affects the immune system and welfare of pullets, and whether effects are persistent later in life. Pullets were reared at either low (13 birds/m2) or high (23 birds/m2) stocking densities but in identical group sizes from wk 7 to 17. Afterward, hens were kept at the same stocking density (2.4 birds/m2) until wk 28. Blood and tissue samples (spleen and cecal tonsils) were collected at the end of the rearing period and in the laying period. The parameters evaluated encompassed number and distribution of leukocytes and lymphocyte subsets in blood and lymphatic tissue, lymphocyte functionality, plasma corticosterone concentrations as well as behavior and physical appearance of hens. At the end of rearing, pullets kept under high stocking density had lower numbers of T lymphocytes, especially γδ T cells in blood, spleen, and cecal tonsils and displayed a higher heterophil to lymphocyte ratio. These effects are mostly persistent during the laying period, although stocking density was identical at this time. Furthermore, birds from the high stocking density group showed less active behavior, more pecking behavior and worse physical appearance throughout both examination periods. In conclusion, stocking density during rearing affects pullets' immune system and behavior not only in the rearing, but also subsequently in the laying period, indicating a strong correlation between health and welfare during rearing and the laying period.

Immune parameters in two different laying hen strains during five production periods.

During life, the number and function of immune cells change with potential consequences for immunocompetence of an organism. In laying hens, studies have primarily focused on early development of immune competence and only few have investigated systemic and lymphatic distribution of leukocyte subsets during adolescence and the egg-laying period. The present study determined the number of various leukocyte types in blood, spleen, and cecal tonsils of 10 Lohmann Brown-Classic and 10 Lohmann LSL-Classic hens per wk of life 9/10, 15/16, 23/24, 29/30, and 59/60, encompassing important production as well as developmental stages, by flow cytometry. Although immune traits differed between the 2 hen strains, identical patterns of age-related immunological changes were found. The numbers of all investigated lymphocyte types in the spleen as well as the numbers of blood γδ T cells increased from wk 9/10 to 15/16. This suggests an ongoing release of lymphocytes from primary lymphoid tissues and an influx of blood lymphocytes into the spleen due to novel pathogen encounters during adolescence. A strong decrease in the number of CTL and γδ T cells and an increase in innate immune cells within blood and spleen were found between wk of life 15/16 and 23/24, covering the transition phase to egg-laying activity. Numbers of peripheral and splenic lymphocytes remained low during the egg-laying period or even further decreased, for example blood CD4+ T cells and splenic γδ T cells. Functional assessments showed that in vitro IFN-γ production of mitogen-stimulated splenocytes was lower in wk 60. Taken together, egg-laying activity seems to alter the immune system toward a more pronounced humoral and innate immune response, with probable consequences for the immunocompetence and thus for productivity, health and welfare of the hens.

Stomatal Responses to Light, CO2, and Mesophyll Tissue in Vicia faba and Kalanchoë fedtschenkoi.

The responses of stomatal aperture to light intensity and CO2 concentration were studied in both Vicia faba (C3) and Kalanchoë fedtschenkoi (Crassulacean acid metabolism; CAM), in material sampled from both light and dark periods. Direct comparison was made between intact leaf segments, epidermises grafted onto exposed mesophyll, and isolated epidermal peels, including transplantations between species and between diel periods. We reported the stomatal opening in response to darkness in isolated CAM peels from the light period, but not from the dark. Furthermore, we showed that C3 mesophyll has stimulated CAM stomata in transplanted peels to behave as C3 in response to light and CO2. By using peels and mesophyll from plants sampled in the dark and the light period, we provided clear evidence that CAM stomata behaved differently from C3. This might be linked to stored metabolites/ions and signalling pathway components within the guard cells, and/or a mesophyll-derived signal. Overall, our results provided evidence for both the involvement of guard cell metabolism and mesophyll signals in stomatal responses in both C3 and CAM species.

Immunomodulatory Effects of Dietary Phosphorus and Calcium in Two Strains of Laying Hens.

Insufficient nutrient supply can impair the immune system, which is important for animal health and welfare. Since chicken can partly hydrolyze phytate, which is the primary phosphorus storage in plant seeds, a reduction of mineral phosphorus in the diets could be an option for more sustainable egg production. Laying hens require high concentrations of calcium that might inhibit the function of endogenous enzymes for phytate hydrolyzation. The objective of this study was to characterize the impact of standard and reduced dietary phosphorus and calcium concentrations on the number and functionality of immune cells in the peripheral and gut-associated immune system in a white and brown laying hen strain. Reduced mineral phosphorus enhanced several immune parameters such as B cells in blood and IgA concentrations in bile in both strains, and peripheral monocytes and γδ T cells in cecal tonsils in brown hens. Reduced calcium levels resulted in lower numbers of T cells in blood and cecal tonsils in both strains, suggesting negative effects on adaptive immunity. Differences between the two strains were found in almost all immune parameters. Results suggest a potentially beneficial effect of reduced dietary mineral phosphorus on the immune system that is dependent on the genetic background.

Intraocular tumor-associated lymphangiogenesis a novel prognostic factor for ciliary body melanomas with extraocular extension?

PURPOSE: To evaluate whether intraocular tumor-associated lymphangiogenesis contributes to prognosis of ciliary body melanomas with extraocular extension and to study its association with other tumor characteristics. DESIGN: Nonrandomized, retrospective case series. PARTICIPANTS: Twenty consecutive patients enucleated for a malignant melanoma of the ciliary body with extraocular extension. METHODS: Lymphatic vessels were identified using lymphatic vascular endothelial-specific hyaluronic acid receptor-1 (LYVE-1) and podoplanin as specific immunohistochemical markers for lymphatic vascular endothelium. Baseline tumor characteristics included intra- and extraocular tumor size, 2009 tumor, node, metastasis (TNM) classification, route of extraocular spread, tumor cell type, mitotic rate, Ki-67 proliferation-index, microvascular patterns and density, tumor-infiltrating lymphocytes and macrophages, and expression of human leukocyte antigen (HLA) class I and insulin-like growth factor-1 receptor. Kaplan-Meier and Cox regression analyses of melanoma-specific survival were performed. MAIN OUTCOME MEASURES: Prevalence of intraocular LYVE-1(+)/podoplanin(+) lymphatic vessels and association with intraocular tumor characteristics and metastasis-free survival. RESULTS: Intraocular LYVE-1(+) and podoplanin(+) lymphatic vessels could be detected in 12 (60%) of 20 ciliary body melanomas with extraocular extension. Presence of intraocular LYVE-1(+)/podoplanin(+) lymphatic vessels was significantly associated with larger intra- (P = 0.002) and extraocular tumor size (P<0.001), higher TNM categories (P = 0.004), epithelioid cellularity (P = 0.016), higher mitotic rate (P = 0.003), higher Ki-67 proliferation-index (P = 0.049), microvascular networks (P = 0.005), higher microvascular density (P = 0.003), more tumor-infiltrating macrophages (P = 0.002), higher expression of HLA class I (P = 0.046), and insulin-like growth factor-1 receptor (P = 0.033), but not significantly with route of extraocular spread (P = 0.803), and tumor-infiltrating lymphocytes (P = 0.069). Melanoma-specific mortality rates increased significantly with the presence of intraocular LYVE-1(+)/podoplanin(+) lymphatic vessels (P = 0.008). By multivariate Cox regression, tumor size (hazard ratio, 14.40; P = 0.002), and presence of intraocular lymphatic vessels (hazard ratio, 8.09; P = 0.04) were strong prognostic predictors of mortality. CONCLUSIONS: Intraocular peritumoral lymphangiogenesis seems to be associated with an increased mortality risk in patients with ciliary body melanomas and extraocular extension. This association may be primarily because of an association of intraocular lymphangiogenesis with greater tumor size and increased malignancy.

Aquagenic pruritus: associated diseases and clinical pruritus characteristics.

BACKGROUND: Aquagenic pruritus (AP) can be induced by systemic diseases. The distribution of underlying diseases in a representative patient collective has not been investigated. This retrospective study aimed to determine the frequency and pruritus-specific parameter of systemic diseases in a series of patients. PATIENTS AND METHODS: Data of 39 patients with AP (24 f, 15 m; mean age: f: 51.3 ± 20.1, m: 57.2 ± 15.0 years) were obtained and statistically evaluated as follows: demographic data, pruritus characteristics, underlying diseases, family history. RESULTS: 30.8 % of patients exhibited polycythemia vera or myelofibrosis (Group 1: G1), in 69.2 % (G2) no underlying disease was found. 25.6 % had lactose intolerance as possible contributing factor. Women were significantly more common in G2 (p < 0.01), with a lower mean age (p < 0.01) and longer duration of AP (18.9 years, p < 0.01). CONCLUSIONS: AP occurs frequently with polycythemia vera. Other underlying diseases are rare; in over half of the patients no cause can be detected. In 25 % lactose intolerance is present which possibly acts as co-factor. Demographic parameters (age, gender) allow estimation of the possible underlying disease in AP. Pruritus characteristics are similar in all groups and not helpful in determining the origin of AP.

Impact of Housing Environment on the Immune System in Chickens: A Review.

During their lifespan, chickens are confronted with a wide range of acute and chronic stressors in their housing environment that may threaten their welfare and health by modulating the immune system. Especially chronic stressful conditions can exceed the individual's allostatic load, with negative consequences for immunity. A fully functional immune system is mandatory for health and welfare and, consequently, also for high productivity and safe animal products. This review provides a comprehensive overview of the impact of housing form, light regime as well as aerial ammonia and hydrogen sulfide concentrations on the immune system in chickens. Certain housing conditions are clearly associated with immunological alterations which potentially impair the success of vaccinations or affect disease susceptibility. Such poor conditions counteract sustainable poultry production. This review also outlines current knowledge gaps and provides recommendations for future research.

Glycosylation is crucial for stability of tumour and cancer stem cell antigen EpCAM.

Epithelial cell adhesion molecule EpCAM is strongly over-expressed in a variety of carcinomas where it is involved in signalling events resulting in increased expression of target genes such as c-Myc, cyclins and others, eventually conferring cells an oncogenic phenotype. However, EpCAM is also expressed in a series of healthy epithelia, albeit generally to a far lesser extend. We have uncovered differential glycosylation of EpCAM as a means to discriminate normal from malignant tissues. EpCAM was hyperglycosylated in carcinoma tissue as compared with autologous normal epithelia. All three N-glycosylation consensus sequences within EpCAM's extracellular domain were used in human and murine cells. We show that glycosylation at asparagine198 is crucial for protein stability. Mutants of EpCAM that substitute asparagine198 for alanine showed a decreased overall expression and half-life of the molecule at the plasma membrane. This is of considerable importance with respect to EpCAM variants expressed in normal tissue, where it might reveal to be less stable and thus may have repercussions on functionality.

A fluorescent broad-spectrum proteasome inhibitor for labeling proteasomes in vitro and in vivo.

The proteasome is an essential evolutionary conserved protease involved in many regulatory systems. Here, we describe the synthesis and characterization of the activity-based, fluorescent, and cell-permeable inhibitor Bodipy TMR-Ahx(3)L(3)VS (MV151), which specifically targets all active subunits of the proteasome and immunoproteasome in living cells, allowing for rapid and sensitive in-gel detection. The inhibition profile of a panel of commonly used proteasome inhibitors could be readily determined by MV151 labeling. Administration of MV151 to mice allowed for in vivo labeling of proteasomes, which correlated with inhibition of proteasomal degradation in the affected tissues. This probe can be used for many applications ranging from clinical profiling of proteasome activity, to biochemical analysis of subunit specificity of inhibitors, and to cell biological analysis of the proteasome function and dynamics in living cells.

Intraocular lymphatics in ciliary body melanomas with extraocular extension: functional for lymphatic spread?

OBJECTIVE: To assess the functional significance of intraocular tumor-associated lymphatic vessels in ciliary body melanomas with extraocular extension. METHODS: Twelve consecutive patients enucleated for a malignant melanoma of the ciliary body with extraocular extension and immunohistochemical presence of intraocular LYVE-1-positive and podoplanin-positive lymphatic vessels were examined for proliferation status and tumor invasion into tumor-associated lymphatics. Proliferating lymphatic vessels were identified using LYVE-1 and podoplanin as specific lymphatic endothelial markers and Ki-67 as the proliferation marker. Tumor invasion into lymphatic vessels was assessed using Melan-A as the melanoma marker. Kaplan-Meier analyses of survival and metastasis were performed. RESULTS: Intraocular proliferating lymphatic vessels were detected in all 12 ciliary body melanomas with extraocular extension. The ratio of proliferating lymphatics was significantly higher in the intraocular vs extraocular tumor compartment (P < .001). Extraocular lymphatic invasion by tumor cells was observed in 5 patients (42%), intraocular lymphatic invasion in 4 (33%), and synchronous intraocular and extraocular lymphatic invasion in 3 (25%). Detection of melanoma cells in intraocular and extraocular lymphatic vessels was significantly associated with higher risks of lymphatic spread (P < .001) and lower metastasis-free survival rates (P = .03). CONCLUSIONS: Intraocular tumor-associated lymphatic vessels contain proliferating endothelial cells and can be invaded by cancer cells in ciliary body melanomas with extraocular extension. Lymphatic invasion by tumor cells seems to be associated with an increased risk of lymphatic spread and mortality in these affected patients.

Activity-based profiling reveals reactivity of the murine thymoproteasome-specific subunit beta5t.

Epithelial cells of the thymus cortex express a unique proteasome particle involved in positive T cell selection. This thymoproteasome contains the recently discovered beta5t subunit that has an uncharted activity, if any. We synthesized fluorescent epoxomicin probes that were used in a chemical proteomics approach, entailing activity-based profiling, affinity purification, and LC-MS identification, to demonstrate that the beta5t subunit is catalytically active in the murine thymus. A panel of established proteasome inhibitors showed that the broad-spectrum inhibitor epoxomicin blocks the beta5t activity and that the subunit-specific antagonists bortezomib and NC005 do not inhibit beta5t. We show that beta5t has a substrate preference distinct from beta5/beta5i that might explain how the thymoproteasome generates the MHC class I peptide repertoire needed for positive T cell selection.

Intraocular lymphangiogenesis in malignant melanomas of the ciliary body with extraocular extension.

PURPOSE: To analyze whether lymphatic vessels can invade the normally alymphatic eye (lymphangiogenesis) in patients with malignant melanoma of the ciliary body with extraocular extension and to correlate these findings with metastasis-free survival. METHODS: Ten enucleated globes with the histopathologically and immunohistochemically (S-100, HMB-45, PNL-2, and Melan-A) confirmed diagnosis of malignant melanoma of the ciliary body with extraocular extension were matched with 10 globes with a ciliary body melanoma without extraocular extension regarding tumor size, cell type, melanin content, mitotic count, vascular networks, and patients' age. In all 20 cases, immunohistochemistry was performed to identify lymphatic vessels by using LYVE-1 and podoplanin as specific markers for lymphatic vascular endothelium. RESULTS: Intraocular LYVE-1(+) and podoplanin(+) lymphatic vessels were detected in 7 of 10 malignant melanomas of the ciliary body with extraocular extension (two of these developed a regional lymph node metastasis). Lymphatic vessels were found only at the tumor periphery directly adjacent to the sclera within the eye, more often in tumors of the epithelioid type (P = 0.017, Mann-Whitney test). Ciliary body melanomas without extrascleral extension revealed no intraocular LYVE-1(+) and podoplanin(+) lymphatic vessels. The presence of intraocular LYVE-1(+)/podoplanin(+) lymphatic vessels was significantly associated with lower metastasis-free survival rates (P = 0.038, log-rank test). CONCLUSIONS: Malignant melanomas of the ciliary body with extraocular extension show intraocular lymphatic vessels. This first evidence of lymphangiogenesis into the normally alymphatic eye may explain the increased risk of lymphatic metastasis in ciliary body melanoma with extraocular extension.

Diatom-derived carbohydrates as factors affecting bacterial community composition in estuarine sediments.

Microphytobenthic biofilms in estuaries, dominated by epipelic diatoms, are sites of high primary productivity. These diatoms exude large quantities of extracellular polymeric substances (EPS) comprising polysaccharides and glycoproteins, providing a substantial pool of organic carbon available to heterotrophs within the sediment. In this study, sediment slurry microcosms were enriched with either colloidal carbohydrates or colloidal EPS (cEPS) or left unamended. Over 10 days, the fate of these carbohydrates and changes in beta-glucosidase activity were monitored. Terminal restriction fragment length polymorphism (T-RFLP), DNA sequencing, and quantitative PCR (Q-PCR) analysis of 16S rRNA sequences were used to determine whether sediment bacterial communities exhibited compositional shifts in response to the different available carbon sources. Initial heterotrophic activity led to reductions in carbohydrate concentrations in all three microcosms from day 0 to day 2, with some increases in beta-glucosidase activity. During this period, treatment-specific shifts in bacterial community composition were not observed. However, by days 4 and 10, the bacterial community in the cEPS-enriched sediment diverged from those in colloid-enriched and unamended sediments, with Q-PCR analysis showing elevated bacterial numbers in the cEPS-enriched sediment at day 4. Community shifts were attributed to changes in cEPS concentrations and increased beta-glucosidase activity. T-RFLP and sequencing analyses suggested that this shift was not due to a total community response but rather to large increases in the relative abundance of members of the gamma-proteobacteria, particularly Acinetobacter-related bacteria. These experiments suggest that taxon- and substrate-specific responses within the bacterial community are involved in the degradation of diatom-derived extracellular carbohydrates.

New Target Genes for Tumor-derived Soluble Factors in Primary Monocytes.

BACKGROUND: Tumor cells have developed several strategies to escape the immune system. One of these strategies consists of the secretion of immunosuppressive factors like interleukin-10 or prostaglandin E2 (PGE2), which impair the immune system. We have demonstrated recently that tumor-derived PGE2 down-regulates the expression of the integrin Mac-1 and the chemokine receptor CCR5 on primary monocytes, resulting in reduced adhesion and migration. MATERIALS AND METHODS: In order to identify new target genes for tumor-derived factors in monocytes, we set up an in vitro system consisting of cDNA micro arrays and 2D gel electrophoresis. RESULTS: We identified 25 genes that were differentially expressed upon incubation of cells in conditioned tumor cell supernatants as compared to cells incubated in cell culture medium. We describe in more detail that IL-1ß secretion is induced by tumor supernatants and that IL-1ß overexpression is also evident in monocytes from tumor patients in vivo, where expression correlates with the tumor stage. In addition, up-regulation of the plasminogen activator inhibitor-2, PAI-2, and down-regulation of the urokinase-type plasminogen activator receptor, uPAR, resulted in a reduced capability of monocytes to degrade and invade extracellular matrices. CONCLUSION: In summary, we describe interesting novel targets of soluble tumor-derived factors that are probably involved in the tumor-mediated immunosuppression commonly found in cancer patients.

The Carcinoma-associated Antigen EpCAM Induces Glyoxalase 1 Resulting in Enhanced Methylglyoxal Turnover.

BACKGROUND: The epithelial cell adhesion molecule (EpCAM) is a homophilic adhesion molecule expressed de novo on a variety of epithelial tumors. Overexpression of EpCAM results in enhanced proliferation and rapid induction of the proto-oncogene c-myc. MATERIALS AND METHODS: The novel proteomics-based fluorescence difference gel electrophoresis (DIGE technology) was used to study EpCAM effects on the proteome of human epithelial cells. RESULTS: DIGE analysis resulted in the identification of five proteins with a significantly changed regulation ranging from -1.3 to +5.8-fold. One of the identified proteins, namely glyoxalase 1, experienced a shift in the isoelectric point from pH 5.2 to 5.0 upon EpCAM expression. This shift correlated with a gain of enzymatic activity of glyoxalase 1 resulting in an enhanced methylglyoxal turnover. CONCLUSION: We show the potential of the DIGE technology to rapidly and quantitatively analyze proteomes for changed expression levels and, importantly, posttranslational modifications. Furthermore, we describe new targets of the carcinoma antigen EpCAM including glyoxalase1.