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1.
In the period 1982-1984 samples of fleas were collected from wild animals of the Middle Scebeli, Low Scebeli and Bay Regions of Somalia. In total 1,335 specimens (486 males and 849 females) were obtained from 17 species of mammalian hosts out of the 19 examined. The following species of fleas were identified: Echidnophaga gallinacea, E. larina, E. murina, Ctenocephalides felis strongylus, Synosternus burtoni, S. somalicus, S. burtoni, S. somalicus, C. felis strongylus and E. larina are known to be widespread in Somalia; on the contrary, the presence of E. gallinacea in this country has not been reported in the literature, though the flea collection of the Institute of Parasitology of the University of Rome owns five females of this species which were collected by Zavattari in South Somalia during the year 1933. Moreover, as far as it is known, E. murina has not been reported in Somalia until now. The spermatheca of the females identified as S. burtoni is described in detail as it shows characteristics which have not been apparently reported before. 相似文献
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M. Pezzella P. Rossi V. Lombardi V. Gemelli R. Mariani Costantini M. Mirolo C. Fundaro V. Moschese H. Wigzell 《BMJ (Clinical research ed.)》1989,298(6675):713-716
A study was conducted to assess the occurrence of latent infection with the human immunodeficiency virus (HIV) among seronegative people at high risk of infection. The presence of HIV genomes was analysed by molecular techniques in two seronegative children born to mothers infected with HIV and in three regular sexual partners of seropositive drug addicts. The adults were selected from a seronegative cohort at high risk of infection because of their sexual contacts and the children selected because of impaired growth. HIV retroviral sequences were detected in four of the five subjects directly at the cellular level by in situ hybridisation in peripheral blood mononuclear cells. HIV genomic sequences were confirmed by in vitro amplification of viral DNA with the polymerase chain reaction technique. The existence of a latent viral infection state in these seronegative subjects indicates the unreliability of standard serological analysis in people who have been in regular contact with infected patients. 相似文献
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V. Costantini P. Fuschiotti A. Giampietri M. Allegrucci G. Agnelli G.G. Nenci M.C. Fioretti 《Prostaglandins & other lipid mediators》1990,39(6)
The stable prostacyclin (PGI2) analogue, iloprost, is a potent inhibitor of both tumor cell-induced platelet aggregation and of experimental metastasis in mice. To explore possible mechanisms of antimetastatic effect of iloprost, we measured the effect of this drug on both platelet aggregation and immunocompetence in the mouse. Iloprost (4×10−8M) inhibited platelet aggregation as induced by a mixture of collagen and epinephrine for at least 180 minutes of incubation, and completely reversed platelet aggregation when added during the second wave of aggregation. In addition, aggregation of platelets obtained from iloprost-treated mice (0.2 mg/kg) was completely inhibited for at least 90 minutes of incubation. Moreover, iloprost pretreatment
counteracted tumor cell-induced thrombocytopenia. Thus, mouse platelets were equally sensitive to the inhibitory effect of iloprost on aggregation as platelets of other species including humans. Effects of iloprost on parameters of host immunocompetence that may influence tumor growth and metastasis formation were also evaluated. Iloprost treatment increased significantly macrophage cytostasis to tumor cells, natural killer (NK) lytic activity of spleen cells and T-cell mediated cytotoxicity
. These results suggested that the antimetastatic effect of iloprost in the mouse may be attributable to multiple mechanisms including inhibition of platelet aggregation and stimulation of certain host immune functions. 相似文献
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Specific binding sites for vasopressin (AVP) were located in subcellular particulate fractions of rat brain with tritiated vasopressin of high specific activity, 22.5 Ci/mmol. Rat brain tissue was dissected, placed in cold 0.32 M sucrose containing proteolytic inhibitors, homogenized and fractionated into a crude nuclear fraction (1K pellet), crude mitochondrial fractions (12K pellet), and plasma membranes and microsomes (100K pellet). Specific binding of vasopressin was found in the 12K and 100K pellets in the presence of a divalent metal ion with Ni greater than Co greater than Mg greater than Mn greater than no metal ion at pH 7.4 in 50 mM Tris-Maleate buffer. Maximum specific binding of 16 nM AVP was located in the 100K anterior cortex fraction which bound 350 fmoles/mg protein; striatum, midbrain/thalamus, cerebellum, and medulla oblongata and pons bound specifically about 200 fmoles/mg protein and frontal poles and parietal cortex about 100 fmoles/mg protein in the 100K pellet. In all of the brain regions studied, except hippocampus and septum, the 100K pellet bound specifically 2 to 4 times more 3H-AVP than the 12K pellet. In the hippocampus with 16 nM AVP, the 12K pellet bound specifically 150 fmoles/mg protein; the septum, 75 fmoles/mg protein. Little or no binding to the 100K pellet was present in these regions. Bound AVP could be dissociated rapidly from the membranes by the addition of EDTA. The 12K hippocampal pellet was further fractionated into myelin, mitochondria, and synaptosomes; purification was confirmed by marker enzyme assays.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Terzin Marko Paletta Maria Grazia Matterson Kenan Coppari Martina Bavestrello Giorgio Abbiati Marco Bo Marzia Costantini Federica 《Coral reefs (Online)》2021,40(4):1391-1391
Coral Reefs - A correction to this paper has been published: https://doi.org/10.1007/s00338-021-02120-y 相似文献
8.
Xiaojiong Lu Todd Costantini Nicole E. Lopez Paul L. Wolf Ann‐Marie Hageny James Putnam Brian Eliceiri Raul Coimbra 《Journal of cellular and molecular medicine》2013,17(5):664-671
Mitochondria play a central role in the integration and execution of a wide variety of apoptotic signals. In the present study, we examined the deleterious effects of burn injury on heart tissue. We explored the effects of vagal nerve stimulation (VNS) on cardiac injury in a murine burn injury model, with a focus on the protective effect of VNS on mitochondrial dysfunction in heart tissue. Mice were subjected to a 30% total body surface area, full‐thickness steam burn followed by right cervical VNS for 10 min. and compared to burn alone. A separate group of mice were treated with the M3‐muscarinic acetylcholine receptor (M3‐AchR) antagonist 4‐DAMP or phosphatidylinositol 3 Kinase (PI3K) inhibitor LY294002 prior to burn and VNS. Heart tissue samples were collected at 6 and 24 hrs after injury to measure changes in apoptotic signalling pathways. Burn injury caused significant cardiac pathological changes, cardiomyocyte apoptosis, mitochondrial swelling and decrease in myocardial ATP content at 6 and 24 hrs after injury. These changes were significantly attenuated by VNS. VNS inhibited release of pro‐apoptotic protein cytochrome C and apoptosis‐inducing factor from mitochondria to cytosol by increasing the expression of Bcl‐2, and the phosphorylation level of Bad (pBad136) and Akt (pAkt308). These protective changes were blocked by 4‐DAMP or LY294002. We demonstrated that VNS protected against burn injury–induced cardiac injury by attenuating mitochondria dysfunction, likely through the M3‐AchR and the PI3K/Akt signalling pathways. 相似文献
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While shallow water red coral populations have been overharvested in the past, nowadays, commercial harvesting shifted its pressure on mesophotic organisms. An understanding of red coral population structure, particularly larval dispersal patterns and connectivity among harvested populations is paramount to the viability of the species. In order to determine patterns of genetic spatial structuring of deep water Corallium rubrum populations, for the first time, colonies found between 58–118 m depth within the Tyrrhenian Sea were collected and analyzed. Ten microsatellite loci and two regions of mitochondrial DNA (mtMSH and mtC) were used to quantify patterns of genetic diversity within populations and to define population structuring at spatial scales from tens of metres to hundreds of kilometres. Microsatellites showed heterozygote deficiencies in all populations. Significant levels of genetic differentiation were observed at all investigated spatial scales, suggesting that populations are likely to be isolated. This differentiation may by the results of biological interactions, occurring within a small spatial scale and/or abiotic factors acting at a larger scale. Mitochondrial markers revealed significant genetic structuring at spatial scales greater then 100 km showing the occurrence of a barrier to gene flow between northern and southern Tyrrhenian populations. These findings provide support for the establishment of marine protected areas in the deep sea and off-shore reefs, in order to effectively maintain genetic diversity of mesophotic red coral populations. 相似文献
10.
Carla Perrotta Silke Kleefeld Anthony Staines Prerna Tewari Anneclaire J. De Roos Dalsu Baris Brenda Birmann Brian Chiu Wendy Cozen Nikolaus Becker Lenka Foretova Marc Maynadié Alexandra Nieters Silvia de Sanjosé Lucia Miligi Adele Seniori Costantini Mark Purdue John Spinelli Pierluigi Cocco 《Cancer epidemiology》2013,37(3):300-305
Objective: We investigated occupational risk of multiple myeloma (MM) in a pooled analysis of five international case–control studies. Methods: We calculated the odds ratio and its 95% confidence interval for selected occupations with unconditional regression analysis in 1959 MM cases and 6192 controls, by pooling study-specific risks using random-effects meta-analysis. Exposure to organic solvents was assessed with a job-exposure matrix (JEM). Results: Gardeners and nursery workers combined, most likely exposed to pesticides, showed a 50% increase in risk (OR = 1.50, 95% CI 0.9–2.3), while other farming jobs did not. Metal processors (OR = 1.55, 95% CI 0.9–2.3), female cleaners (OR = 1.32, 95% CI 1.0–1.8), and high level exposure to organic solvents (OR = 1.38, 95% CI 0.96–1.8) also showed moderately increased risks. Conclusions: Additional case–control studies of MM aetiology are warranted to further investigate the nature of the repeatedly reported increase in MM risk in several occupational groups. 相似文献