Clock Genes, Melanopsins, Melatonin, and Dopamine Key Enzymes and Their Modulation by Light and Glutamate in Chicken Embryonic Retinal Cells

The avian circadian system is composed of the retina, the mammalian homolog region of the suprachiasmatic nucleus (SNC), and the pineal gland. The retina, itself, displays many rhythmic physiological events, such as movements of photoreceptor cells, opsin expression, retinal reisomerization, and melatonin and dopamine production and secretion. Altogether, these rhythmic events are coordinated to predict environmental changes in light conditions during the day, optimizing retina function. The authors investigated the expression pattern of the melanopsin genes Opn4x and Opn4m, the clock genes Clock and Per2, and the genes for the key enzymes N-Acetyltransferase and Tyrosine Hidroxylase in chicken embryo dispersed retinal cells. Primary cultures of chicken retina from 8-day-old embryos were kept in constant dark (DD), in 12-h light/12-h dark (12L:12D), in 12L:12D followed by DD, or in DD in the absence or presence of 100 mu M glutamate for 12 h. Total RNA was extracted throughout a 24-h span, every 3 h starting at zeitgeber time 0 (ZT0) of the 6th day, and submitted to reverse transcriptase-polymerase chain reaction (RT-PCR) followed by quantitative PCR (qPCR) for mRNA quantification. The data showed no rhythmic pattern of transcription for any gene in cells kept in DD. However under a light-dark cycle, Clock, Per2, Opn4m, N-Acetyltransferase, and Tyrosine Hydroxylase exhibited rhythmic patterns of transcription. In DD, 100 mu M glutamate was able to induce rhythmic expression of Clock, strongly inhibited the expression of Tyrosine Hydroxylase, and, only at some ZTs, of Opn4x and Opn4m. The neurotransmitter had no effect on Per2 and N-Acetyltransferase transcription. The authors confirmed the expression of the protein OPN4x by immunocytochemistry. These results suggest that chicken embryonic retinal cells contain a functional circadian clock, whose synchronization requires light-dark cycle or glutamate stimuli. (Author correspondence: amdlcast@ib.usp.br).

A new genus of Ectinosomatidae (Copepoda, Harpacticoida) from sublittoral sediments in Ubatuba, Sao Paulo State (Brazil), an updated key to genera and notes on Noodtiella Wells, 1965

Both sexes of a new genus and species of Ectinosomatidae (Copepoda, Harpacticoida) from sublittoral sediments collected on the inner continental shelf in Ubatuba, Sao Paulo State (Brazil) are described in detail. Chaulionyx gen. n. (type species: C. paivacarvalhoi sp. n.) differs from all known genera in the presence of a conspicuous bifid spine on the prehensile P1 endopod. It can be differentiated from other genera with a prehensile endopod (Halophytophilus Brian, 1919; Bradyellopsis Brian, 1925; Klieosoma Hicks & Schriever, 1985) by the presence of distinctive subrectangular middorsal pores on the urosomites and the unarmed male sixth legs. The genus Lineosoma Wells, 1965 is recognized as a paraphyletic taxon and relegated to a junior subjective synonym of Noodtiella Wells, 1965. Arenosetella pectinata Chappuis, 1954a is removed from its floating position in Ectinosomoides Nicholls, 1945, transferred to the genus Noodtiella as N. pectinata comb. n. and considered the senior subjective synonym of N. toukae Mitwally & Montagna, 2001. Dichotomous keys are provided for the identification of the 18 valid species of Noodtiella and the 21 valid genera of the family Ectinosomatidae. Halophytophilus aberrans Wells & Rao, 1987 is placed species incertae sedis in the family.

New genera of philopotine spider flies (Diptera, Acroceridae) with a key to living and fossil genera

In this paper we describe two new genera of philopotine Acroceridae: Schlingeriella irwini gen. et sp. n. (New Caledonia) and Quasi fisheri gen. et sp. n. (Mexico). The Baltic amber species Eulonchiella eocenica Meunier, 1912 is rediagnosed and a neotype designated based on a newly discovered specimen. We also provide a dichotomous key to the world genera of Philopotinae, both living and fossil.

Specific leaf areas of the tank bromeliad Guzmania monostachia perform distinct functions in response to water shortage

Leaves comprise most of the vegetative body of tank bromeliads and are usually subjected to strong longitudinal gradients. For instance, while the leaf base is in contact with the water accumulated in the tank, the more light-exposed middle and upper leaf sections have no direct access to this water reservoir. Therefore, the present study attempted to investigate whether different leaf portions of Guzmania monostachia, a tank-forming C(3)-CAM bromeliad, play distinct physiological roles in response to water shortage, which is a major abiotic constraint in the epiphytic habitat. Internal and external morphological features, relative water content, pigment composition and the degree of CAM expression were evaluated in basal, middle and apical leaf portions in order to allow the establishment of correlations between the structure and the functional importance of each leaf region. Results indicated that besides marked structural differences, a high level of functional specialization is also present along the leaves of this bromeliad. When the tank water was depleted, the abundant hydrenchyma of basal leaf portions was the main reservoir for maintaining a stable water status in the photosynthetic tissues of the apical region. In contrast, the CAM pathway was intensified specifically in the upper leaf section, which is in agreement with the presence of features more suitable for the occurrence of photosynthesis at this portion. Gas exchange data indicated that internal recycling of respiratory CO(2) accounted for virtually all nighttime acid accumulation, characterizing a typical CAM-idling pathway in the drought-exposed plants. Altogether, these data reveal a remarkable physiological complexity along the leaves of G. monostachia, which might be a key adaptation to the intermittent water supply of the epiphytic niche. (C) 2009 Elsevier GmbH. All rights reserved.

The Muscini flies of the world (Diptera, Muscidae): identification key and generic diagnoses

Flies of the tribe Muscini (Diptera, Muscidae) are worldwide in distribution and are represented by some 350 species in 18 genera. The present study provides an identification key and diagnoses for all the genera of world Muscini: Biopyrellia Townsend, Curranosia Paterson, Dasyphora Robineau-Desvoidy, Deltotus Seguy, Hennigmyia Peris, Mesembrina Meigen, Mitroplatia Enderlein, Morellia Robineau-Desvoidy, Musca Linnaeus, Myiophaea Enderlein, Neomyia Walker, Neorypellia Pont, Polietes Rondani, Polietina Schnabl & Dziedzicki, Pyrellia Robineau-Desvoidy, Pyrellina Malloch, Sarcopromusca Townsend, Ziminellia Nihei & de Carvalho. Most infrageneric taxa are also represented, namely, the sub-genera of Dasyphora and Morellia. Comments on phylogeny support (whenever pertinent) and the major references containing revisions and regional identification keys to species are provided for each genus and subgenus.

Mannose-binding lectin complement pathway plays a key role in complement activation by Paracoccidioides brasiliensis

Paracoccidioides brasiliensis (Pb) is a dimorphic fungal pathogen that causes paracoccidioidomycosis the most severe deep mycosis from South America Although cell mediated immunity is considered the most efficient protective mechanism against Pb infection mechanisms of innate immunity are poorly defined Herein we investigated the interaction of the complement system with high and low virulence isolates of Pb We demonstrated that Pb18 a high virulence Pb Isolate when incubated with normal human serum (NHS) induces consumption of hemolytic complement and when immobilized promotes binding of C4b C3b and C5b-C9 Both low virulence (Pb265) and high virulence (Pb18) isolates consumed C4 C3 and mannose-binding learn (MBL) of MBL-sufficient but not of MBL-deficient serum as revealed by deposition of residual C4 C3 and MBL on immune complexes and mannan However higher complement components consumption was observed with Pb265 as compared with Pb18 The suggested relationship between low virulence and significant complement activation properties of Pb isolates was confirmed by the demonstration that virulence attenuation of Pb 18 results in acquisition of the ability to activate complement Conversely reactivation of attenuated Pb18 results in loss of the ability to activate complement Our results demonstrate for the first time that Pb yeasts activate the complement system by the lectin pathway and there is an Inverse correlation between complement activating ability and Pb virulence These differences could exert an influence on Innate immunity and severity of the disease developed by infected hosts (C) 2010 Elsevier Ltd All rights reserved

Quantitative structure-activity studies on a series of migrastatin analogs as inhibitors of cancer cell metastasis

Migrastatin, a macrolide natural product, and its structurally related analogs are potent inhibitors of cancer cell metastasis, invasion and migration. In the present work, a specialized fragment-based method was employed to develop QSAR models for a series of migrastatin and isomigrastatin analogs. Significant correlation coefficients were obtained (best model, q(2) = 0.76 and r(2) = 0.91) indicating that the QSAR models possess high internal consistency. The best model was then used to predict the potency of an external test set, and the predicted values were in good agreement with the experimental results (R(2) (pred) = 0.85). The final model and the corresponding contribution maps, combined with molecular modeling studies, provided important insights into the key structural features for the anticancer activity of this family of synthetic compounds based on natural products.

Peroxymonocarbonate and Carbonate Radical Displace the Hydroxyl-like Oxidant in the Sod1 Peroxidase Activity under Physiological Conditions

Despite being one of the most important antioxidant defenses, Cu,Zn-superoxide dismutase (Sod1) has been frequently associated with harmful effects, including neurotoxicity. This toxicity has been attributed to immature forms of Sod1 and extraneous catalytic activities. Among these, the ability of Sod1 to function as a peroxidase may be particularly relevant because it is increased in bicarbonate buffer and produces the reactive carbonate radical. Despite many studies, how this radical forms remains unknown. To address this question, we systematically studied hSod1 peroxidase activity in the presence of nitrite, formate, and bicarbonate-carbon dioxide. Kinetic analyses of hydrogen peroxide consumption and of nitrite, formate, and bicarbonate-carbon dioxide oxidation showed that the Sod1-bound hydroxyl-like oxidant functions in the presence of nitrite and formate. In the presence of bicarbonate-carbon dioxide, this oxidant is replaced by peroxymonocarbonate, which is then reduced to the carbonate radical. Peroxymonocarbonate intermediacy was evidenced by (13)C NMR experiments showing line broadening of its peak in the presence of Zn,ZnSod1. In agreement, peroxymonocarbonate was docked into the hSod1 active site, where it interacted with the conserved Arg(143). Also, a reaction between peroxymonocarbonate and Cu(I)Sod1 was demonstrated by stopped-flow experiments. Kinetic simulations indicated that peroxymonocarbonate is produced during Sod1 turnover and not in bulk solution. In the presence of bicarbonate-carbon dioxide, sustained hSod1-mediated oxidations occurred with low steady-state concentrations of hydrogen peroxide (4-10 mu M). Thus, carbonate radical formation through peroxymonocarbonate may be a key event in Sod1-induced toxicity.

The Key Role of the School Principal’s Leadership in the Schooling of Newly Arrived Immigrant Pupils in Sweden : Experiences from an Interactive Action Research Project

When newly immigrated children and young people begin school in Sweden, certain challengesarise. These may result from weak Swedish-language skills and different schooling backgrounds,as well as organizational and pedagogical limitations in the schools. This generates demands onschool leaders to lead and develop the organization and teachers competences to meet these pupils’needs. This situation was behind the initiation of the project “New Immigrants and Learning—Competence Development for Teachers and School Principals.” The project ran in schools infour Swedish municipalities, its aim was to develop leadership, organizational and pedagogicalskills that would facilitate the schooling and integration of newly arrived pupils. This article aimsto describe and discuss a Participant Action Research (PAR) based on a think tank and researchcircles, drawing special attention to the role of the school leaders. It will also examine whether theresearch circles and the project overall served to develop educational and intercultural leadership,organizational conditions, collegial learning, pedagogical methods and competence in terms ofschooling for this pupil group.

Projektarbete i praktiken : Hur kan oförutsedda problem vid projektöverlämningen minimeras

Projektarbete förekommer på många företag och trots att det ofta finns tydligt beskrivna rutiner för hur projektarbetet skall ske händer det att parterna inte är helt överens då projektet ska avslutas. Ibland är det ändringar under projektets gång som ligger till grund för kommande tvister, men i grunden är det oftast kommunikationen som brister mellan parterna. Genom att intervjua några olika företag och analyserat hur de arbetar i projekt har vi i detta arbete kunnat se en röd tråd som består av den viktiga kommunikationen för att skapa och bibehålla sunda relationer. För att hantera de förändringar som kan ske under projektresans gång ser vi i vår analys av de företag som ingått i vår studie att det är av fördel att ha ett nära samarbete med kunder eller leverantörer och helst starta samarbetet tidigt för att möjliggöra justeringar som annars i ett senare skede blir svårare att genomföra. Ett tillvägagångssätt att arbeta med ett projekts interna problem kan vara plattformar som möjliggör en delning av information mellan projektets olika medlemmar. Angreppsvinkeln är då att det ska bli lättare för att samtliga projektdeltagare att kunna ta del av informationen med en förhoppning att minimera missförstånd inom projektet.