Biochemical and pharmacological characterization of adenosine A1 receptors in eel (Anguilla anguilla) brain     

A. Poli  B. Pavan  R. Lucchi  P. G. Borasio  E. Fabbri  R. Rossi 《Fish physiology and biochemistry》1997,16(1):19-27

N⁶-cyclohexyl[³H]adenosine ([³H]CHA) was used to label adenosine A1 receptors in membranes prepared from male and female eel whole brain. The A1 receptor agonist [³H]CHA bound saturably, reversibly and with high affinity (K_d = 0.91 ± 0.12 nM; B_max = 120.36 ± 5.2 fmol mg⁻¹ protein). In equilibrium competition experiments, the adenosine agonists and antagonists all displaced [³H]CHA from high-affinity binding sites with the rank order of potency in displacing, characteristics of an A1 adenosine receptor. Mg²⁺ dramatically increased the affinity of [³H]CHA without modifying the maximal binding capacity. The specific binding was inhibited by guanosine 5′-triphosphate (K_i = 2.54 ± 0.98 μM). The [³H]CHA binding sites are ubiquitously distributed with a maximum in cerebellum and a minimum in olfactory bulb. No difference was observed between male and female brain. In eel brain, synaptosomes (P2), stimulation of adenosine 3′,5′-monophosphate (cyclic AMP) accumulation with 10⁻⁵ M forskolin was markedly reduced (45.5%) by treatment with the adenosine A1 receptor agonist CHA (10⁻⁴ M), and the reduction was reversed in presence of the selective A1 receptor antagonist 8-cyclopentyltheophylline (10⁻⁵ M). In superfused eel cerebellar synaptosomes, K⁺ stimulated the release of adenosine in a partially Ca²⁺-dependent manner. The findings, taken together, suggest the hypothesis that adenosine A1 receptors present in eel brain could modulate synaptic transmission, as A1 receptors do in other vertebrates.  相似文献   

EGFR overexpression in canine primary lung cancer: pathogenetic implications and impact on survival     

S. Sabattini  F. R. Mancini  L. Marconato  B. Bacci  F. Rossi  M. Vignoli  G. Bettini 《Veterinary and comparative oncology》2014,12(3):237-248

This study reports the main clinicopathological features of primary lung cancer (PLC) in 37 dogs, with special regard to the pathogenetic and prognostic role of epidermal growth factor receptor (EGFR) overexpression. For each case the following characteristics were evaluated: tumour‐node‐metastasis (TNM) stage, tumour histotype, histological grade, mitotic activity and immunohistochemical expression of EGFR. In samples with available normal lung tissue, the amount of background anthracosis was also measured by image analysis. In 27 tumours (73%) a variable number of cells (20–100%) stained positively for EGFR. The proportion of EGFR‐positive tumours was significantly higher in cases with background anthracosis, and the amount of anthracosis was correlated with the percentage of positive tumour cells. Additionally, a trend towards shortened survival for the high EGFR group was observed. These findings suggest an involvement of EGFR signalling pathway in canine PLC, a negative prognostic significance of protein overexpression and its potential implication in air pollution carcinogenesis.  相似文献   

Ribozymes as potential anti-HIV-1 therapeutic agents   总被引：87，自引：0，他引：87  

N Sarver  E M Cantin  P S Chang  J A Zaia  P A Ladne  D A Stephens  J J Rossi 《Science (New York, N.Y.)》1990,247(4947):1222-1225

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Mutations induced in Tradescantia by small doses of x-rays and neutrons: analysis of dose-Response curves   总被引：1，自引：0，他引：1  

A H Sparrow  A G Underbrink  H H Rossi 《Science (New York, N.Y.)》1972,176(37):916-918

Dose-response curves for pink somatic mutations in Tradescantia stamen hairs were analyzed after neutron and x-ray irradiation with doses ranging from a fraction of a rad to the region of saturation. The dose-effect relation for neutrons indicates a linear dependence from 0.01 to 8 rads; between 0.25 and 5 rads a linear dependence is indicated for x-rays also. As a consequence the relative biological effectiveness reaches a constant value (about 50) at low doses. The observations are in good agreement with the predictions of the theory of dual radiation action and support its interpretation of the effects of radiation on higher organisms. The doubling dose of x-rays was found to be nearly I rad.  相似文献   

The urban homeless: estimating composition and size   总被引：6，自引：0，他引：6  

P H Rossi  J D Wright  G A Fisher  G Willis 《Science (New York, N.Y.)》1987,235(4794):1336-1341

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Parallel and serial neural mechanisms for visual search in macaque area V4     

Bichot NP  Rossi AF  Desimone R 《Science (New York, N.Y.)》2005,308(5721):529-534

To find a target object in a crowded scene, a face in a crowd for example, the visual system might turn the neural representation of each object on and off in a serial fashion, testing each representation against a template of the target item. Alternatively, it might allow the processing of all objects in parallel but bias activity in favor of those neurons that represent critical features of the target, until the target emerges from the background. To test these possibilities, we recorded neurons in area V4 of monkeys freely scanning a complex array to find a target defined by color, shape, or both. Throughout the period of searching, neurons gave enhanced responses and synchronized their activity in the gamma range whenever a preferred stimulus in their receptive field matched a feature of the target, as predicted by parallel models. Neurons also gave enhanced responses to candidate targets that were selected for saccades, or foveation, reflecting a serial component of visual search. Thus, serial and parallel mechanisms of response enhancement and neural synchrony work together to identify objects in a scene. To find a target object in a crowded scene, a face in a crowd for example, the visual system might turn the neural representation of each object on and off in a serial fashion, testing each representation against a template of the target item. Alternatively, it might allow the processing of all objects in parallel but bias activity in favor of those neurons that represent critical features of the target, until the target emerges from the background. To test these possibilities, we recorded neurons in area V4 of monkeys freely scanning a complex array to find a target defined by color, shape, or both. Throughout the period of searching, neurons gave enhanced responses and synchronized their activity in the gamma range whenever a preferred stimulus in their receptive field matched a feature of the target, as predicted by parallel models. Neurons also gave enhanced responses to candidate targets that were selected for saccades, or foveation, reflecting a serial component of visual search. Thus, serial and parallel mechanisms of response enhancement and neural synchrony work together to identify objects in a scene.  相似文献   

Something in the eye of the beholder     

Blau H  Brazelton T  Keshet G  Rossi F 《Science (New York, N.Y.)》2002,298(5592):361-2; author reply 362-3

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Is ITS-2 rDNA suitable marker for genetic characterization of Sarcoptes mites from different wild animals in different geographic areas?     

S. Alasaad  D. Soglia  V. Spalenza  S. Maione  R.C. Soriguer  J.M. Pérez  R. Rasero  M.P. Ryser Degiorgis  H. Nimmervoll  X.Q. Zhu  L. Rossi 《Veterinary parasitology》2009

The present study examined the relationship among individual Sarcoptes scabiei mites from 13 wild mammalian populations belonging to nine species in four European countries using the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) as genetic marker. The ITS-2 plus primer flanking 5.8S and 28S rDNA (ITS-2+) was amplified from individual mites by polymerase chain reaction (PCR) and the amplicons were sequenced directly. A total of 148 ITS-2+ sequences of 404 bp in length were obtained and 67 variable sites were identified (16.59%). UPGMA analyses did not show any geographical or host-specific clustering, and a similar outcome was obtained using population pairwise Fst statistics. These results demonstrated that ITS-2 rDNA does not appear to be suitable for examining genetic diversity among mite populations.  相似文献   

Early life history of the black anglerfish Lophius budegassa Spinola, 1807 in the Mediterranean Sea using otolith microstructure     

Mario La Mesa  Francesca De Rossi 《Fisheries Research》2008,93(1-2):234-239

The early life history of the black anglerfish, Lophius budegassa was investigated by otolith (lapilli) increment analysis. Samples of demersal juvenile L. budegassa ranging from 54 to 196 mm total length were collected during bottom trawl surveys in the central Adriatic Sea. By counting increments presumed to be deposited daily in the lapillar otoliths, 88 specimens of L. budegassa were successfully aged. Age estimates of juveniles ranged between 79 and 204 days, indicating that probably the pelagic phase of this species is relatively short and settlement occurs at less than 3 months of life. The analysis of check marks in the core area of lapilli enabled us to determine the period of endogenous feeding, which would last between 15 and 24 days after hatching. Back-calculated hatching dates and, consequently, the spawning season of L. budegassa in the Adriatic Sea was spread over a long period, lasting at least from February to June. The length at age relationship gave an estimate of mean growth rate of approximately 0.8–1.02 mm/day, indicating a faster growth rate of 0+ juveniles L. budegassa than previously thought. The implications of these findings on age estimates discrepancies between previous ageing studies on L. budegassa carried out using different calcified structure (sagittae or illicia) are discussed.  相似文献