Histochemical Analysis of Glycoconjugates in the Skin of a Catfish (Arius Tenuispinis, Day)

A histochemical study using conventional carbohydrate histochemistry (periodic-acid staining including diastase controls, alcian blue staining at pH 1 and 2.5) as well as using a battery of 14 fluorescein isothiocyanate (FITC)-labelled lectins to identify glycoconjugates present in 10 different areas of the skin of a catfish (Arius tenuispinis) was carried out. The lectins used were: mannose-binding lectins (Con A, LCA and PSA), galactose-binding lectins (PNA, RCA), N-acetylgalactosamine-binding lectins (DBA, SBA, SJA and GSL I), N-acetylglucosamine-binding lectins (WGA and WGAs), fucose-binding lectins (UEA) and lectins which bind to complex carbohydrate configurations (PHA E, PHA L). Conventional glycoconjugate staining (PAS staining, alcian blue at pH 1 and 2.5) showed that the mucous goblet cells contain a considerable amount of glycoconjugates in all locations of the skin, whereas the other unicellular gland type, the club cells, lacked these glycoconjugates. The glycoproteins found in goblet cells are neutral and therefore stain magenta when subjected to PAS staining. Alcian blue staining indicating acid glycoproteins was distinctly positive at pH 1, but gave only a comparable staining at pH 2.5. The mucus of the goblet cells therefore also contains acid glycoproteins rich in sulphate groups. Using FITC-labelled lectins, the carbohydrate composition of the glycoproteins of goblet cells could be more fully characterized. A distinct staining of the mucus of goblet cells was found with the mannose-binding lectins LCA and PSA; the galactosamine-binding lectins DBA, SBA and GLS I; the glucosamine-binding lectin WGA; and PHA E which stains glycoproteins with complex carbohydrate configurations. No reaction occurred with the fucose-binding lectin UEA and the sialic acid-specific lectin SNA. In addition, the galactose-binding lectins PNA and RCA showed only a weak or completely negative staining of the mucus in the goblet cells. The specificity of the lectin staining could be proved by inhibiting binding of the lectins by competitive inhibition with the corresponding sugars. From these data, we can conclude that the mucus produced by the epidermal goblet cells of A. tenuispinis is rich in mannose, N-acetylgalactosamine and N-acetylglucosamine residues

Histochemical Analysis of Glycoconjugates in the Skin of a Catfish (Arius Tenuispinis, Day)

A histochemical study using conventional carbohydrate histochemistry (periodic-acid staining including diastase controls, alcian blue staining at pH 1 and 2.5) as well as using a battery of 14 fluorescein isothiocyanate (FITC)-labelled lectins to identify glycoconjugates present in 10 different areas of the skin of a catfish (Arius tenuispinis) was carried out. The lectins used were: mannose-binding lectins (Con A, LCA and PSA), galactose-binding lectins (PNA, RCA), N-acetylgalactosamine-binding lectins (DBA, SBA, SJA and GSL I), N-acetylglucosamine-binding lectins (WGA and WGAs), fucose-binding lectins (UEA) and lectins which bind to complex carbohydrate configurations (PHA E, PHA L). Conventional glycoconjugate staining (PAS staining, alcian blue at pH 1 and 2.5) showed that the mucous goblet cells contain a considerable amount of glycoconjugates in all locations of the skin, whereas the other unicellular gland type, the club cells, lacked these glycoconjugates. The glycoproteins found in goblet cells are neutral and therefore stain magenta when subjected to PAS staining. Alcian blue staining indicating acid glycoproteins was distinctly positive at pH 1, but gave only a comparable staining at pH 2.5. The mucus of the goblet cells therefore also contains acid glycoproteins rich in sulphate groups. Using FITC-labelled lectins, the carbohydrate composition of the glycoproteins of goblet cells could be more fully characterized. A distinct staining of the mucus of goblet cells was found with the mannose-binding lectins LCA and PSA; the galactosamine-binding lectins DBA, SBA and GLS I; the glucosamine-binding lectin WGA; and PHA E which stains glycoproteins with complex carbohydrate configurations. No reaction occurred with the fucose-binding lectin UEA and the sialic acid-specific lectin SNA. In addition, the galactose-binding lectins PNA and RCA showed only a weak or completely negative staining of the mucus in the goblet cells. The specificity of the lectin staining could be proved by inhibiting binding of the lectins by competitive inhibition with the corresponding sugars. From these data, we can conclude that the mucus produced by the epidermal goblet cells of A. tenuispinis is rich in mannose, N-acetylgalactosamine and N-acetylglucosamine residues

Effects of ammonia toxicity on growth performance, cortisol, glucose and hematological response of Nile Tilapia (Oreochromis niloticus)

Ammonia is a production limiting factor in the aquaculture media affecting fish production. A study was designed to scrutinize effects of ammonia on growth performance, survival, cortisol and hematological parameters of Tilapia fish. The study examined effects of 96 h-incubation of male and female Tilapia with 3 mg ammonium chloride per a liter of water compared to control. The study has been carried out in the physiology laboratory of the department of animal and fish production, Alexandria University. Fourteen aquaria were used (6 control and 8 ammoniated). Each aquarium contained 6 fish (half the population males and the other have females). Duration of the control reared fish was 30 days, however the duration for ammoniated group was 4 days. In all stressed fish, there found decreases in final body weight, average daily gain and specific growth rate as compared to controls. Hematological parameters revealed increases (P0.05) in total leukocyte counts in both males and females exposed to stressors. There were significant decreases (P0.05) in red blood cell, hematocrit value and hemoglobin concentration in both males and females. There were non-significant differences (P0.10) in these parameters between males and females. Exposing both male and female tilapia to ammonia, resulted in increases (P0.05) in mean corpuscular volume (MCV). Mean corpuscular hemoglobin (MCH) didn’t change in male tilapia, while females expressed increased MCH values in the ammonia condition. Mean corpuscular hemoglobin concentration (MCHC) decreased (P0.05) under ammonia with no differences between males and females. Differential leukocyte count exhibited increases (P0.05) in neutrophils in ammonia-exposed males and females and decreases (P0.05) in eosinophils and monocytes in males, but not in females. However, lymphocytes decreased (P0.05) in both females and males exposed to ammonia. Cortisol level increased (P0.05) by about 2 folds in both sexes of fish exposed to ammonia (2.95 and 2.72 vs6.40 and 6.48 ng/ml in control males and females vs ammonia-exposed males and females).Rearing tilapia fish in media containing high level (3mg/l water) of ammonium chloride not only deteriorated growth rate but it also negatively affected the health wellbeing.

(E,E)-1,2-Bis[3-meth­oxy-4-(prop-2-yn-1-yl­oxy)benzyl­idene]hydrazine

The complete mol­ecule in the title compound, C22H20N2O4, is generated by the application of an inversion centre. With the exception of the terminal acetyl­ene groups [C—O—C—C = −78.02 (17)°], the remaining atoms constituting the mol­ecule are essentially coplanar. The configuration around the C=N bond [1.282 (2) Å] is E. The formation of supra­molecular chains mediated by C—H⋯O inter­actions, occurring between methyl­ene H and meth­oxy O atoms, is the most notable feature of the crystal packing

Effect of acidity and salt content on the keeping quality of butter

Szerzők kísérletei szerint a vaj eltarthatósága a tejszín aciditásának növekedésével fokozatosan csökken. Édes tejszínből, ill. közepes és nagy aciditású tejszínből készült sózatlan vaj 5 C°-on jól eltartható volt 135, ill. 105 és 75 napig. Sózott vajak eltarthatósága rosszabb volt amint a sózatlan vajaké. Édes tejszínből, ill. közepes és nagy aciditású tejszínből készült sózott vajak eltarthatósága 5 C°-on való tárolásakor 105, ill. 90 és 45 nap volt. Nach den Versuchsangaben vermindert sich die Lagerfähigkeit der Butter stufenweise mit der Erhöhung der Azidität der Sahne. Aus süsser Sahne bzw. aus Sahne von mittlerer und hoher Azidität hergestellte ungesalzte Butter war bei 5°C 135 bzw. 105 und 75 Tage lang lagerfähig. Die Lagerfähigkeit von gesalzten Buttern war schlechter als die der ungesalzten Butter. Gesalzte Butter aus süsser Sahne bzw. aus Sahne von mittlerer und hoher Azidität war bei Lagerung bei 5 °C 105 bzw. 90 und 45 Tage lang lagerfähig. According to the experimental results the keeping quality of butter gradually decreased with the increase of acidity of the cream. Unsalted butter manufactured from sweet cream and cream of moderate and high acidity, respectively, exhibited a keeping quality of 135, 105 and 75 days on storage at 5°C. Salted butters showed lower keeping quality than unsalted butters.Salted butter manufactured from sweet cream and cream of moderate and high acidity, respectively, showed a keeping quality of 105, 90 and 45 days on storage at 5 °C. Selon les expériences des auteurs la stockabilité du beurre diminue avec I’augmentation de l’acidité de la creme. Les beurres non salés, produits ä partir des cremes douce, ä acidité faible et forte se faisaient bien entreposer ä 5°C pendant des périodes respectives de 135, 105 et 75 jours. La stickabilité des beurres sales était inférieure ä celle des non salés. La stockabilité des beurres salés, fabriqués ä partir de cremes douce, d’acidité faible ou forte durait, ä 5°C, 105, 95 et 45 jours

An Analysis of Private School Closings

We add to the small literature on private school supply by exploring exits of K-12 private schools. We find that the closure of private schools is not an infrequent event, and use national survey data from the National Center for Education Statistics to study closures of private schools. We assume that the probability of an exit is a function of excess supply of private schools over the demand, as well as the school's characteristics such as age, size, and religious affiliation. Our empirical results generally support the implications of the model. Working Paper 07-0

Scientists' Warning to Humanity on Threats to Indigenous and Local Knowledge Systems

The knowledge systems and practices of Indigenous Peoples and local communities play critical roles in safeguarding the biological and cultural diversity of our planet. Globalization, government policies, capitalism, colonialism, and other rapid social-ecological changes threaten the relationships between Indigenous Peoples and local communities and their environments, thereby challenging the continuity and dynamism of Indigenous and Local Knowledge (ILK). In this article, we contribute to the “World Scientists' Warning to Humanity,” issued by the Alliance of World Scientists, by exploring opportunities for sustaining ILK systems on behalf of the future stewardship of our planet. Our warning raises the alarm about the pervasive and ubiquitous erosion of knowledge and practice and the social and ecological consequences of this erosion. While ILK systems can be adaptable and resilient, the foundations of these knowledge systems are compromised by ongoing suppression, misrepresentation, appropriation, assimilation, disconnection, and destruction of biocultural heritage. Three case studies illustrate these processes and how protecting ILK is central to biocultural conservation. We conclude with 15 recommendations that call for the recognition and support of Indigenous Peoples and local communities and their knowledge systems. Enacting these recommendations will entail a transformative and sustained shift in how ILK systems, their knowledge holders, and their multiple expressions in lands and waters are recognized, affirmed, and valued. We appeal for urgent action to support the efforts of Indigenous Peoples and local communities around the world to maintain their knowledge systems, languages, stewardship rights, ties to lands and waters, and the biocultural integrity of their territories—on which we all depend.Peer reviewe

A Collaborative Assessment Process for Sustained Curriculum Improvement in Natural Resources and Environmental Management

In this poster, assessment activities in Natural Resources and Environmental management (NREM) were designed to address three critical questions: (1) Are NREM graduate degree program student learning outcomes (SLOs) still appropriate?; (2) Do current core departmental graduate courses adequately address graduate degree program SLOs?; and (3) If current core and elective courses do not adequately cover the existing SLOs, how can they be modified to do so? The NREM Curriculum Committee gathered answers through multiple, collaborative activities inclusive of both graduate students and faculty. In total, the assessment process and implementation included input collected during departmental faculty meetings, faculty and student meetings, collaborative Google documents, faculty workshops, and departmental retreats. This poster describes the concrete strategies and steps through which facilitated collaboration occurred over key milestones of the overall program assessment process. This poster summarizes challenges encountered, such as engaging instructional, research and extension faculty from Oahu and neighbor islands and outlines success strategies and suggestions for other programs to utilize a facilitated collaborative process to move program assessment forward