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991.
Stefania Agostini Cristina Bolzati Eliana Didonè Mario Cavazza-Ceccato Fiorenzo Refosco Luigi Aloj Claudio Arra Michela Aurilio Anna Lucia Tornesello Diego Tesauro Giancarlo Morelli 《Journal of peptide science》2007,13(4):211-219
The radiolabeling of the natural octapeptide CCK8, derivatized with a cysteine residue (Cys-Gly-CCK8), by using the metal fragment [99mTc(N)(PNP3)]2+ (PNP3 = N,N-bis(dimethoxypropylphosphinoethyl)methoxyethylamine) is reported. The [99mTc(N)(NS-Cys-Gly-CCK8)(PNP3)]+ complex was obtained according to two methods (one-step or two-step procedure) that gave the desired compound in high yield. The complex is stable in aqueous solution and in phosphate buffer. In vitro challenge experiments with an excess of cysteine and glutathione indicate that no transchelation reactions occur, confirming the high thermodynamic stability and kinetic inertness of this compound. Stability studies carried out in human and mouse serum, as well as in mouse liver homogenates, show that the radiolabeled compound remains intact for prolonged incubation at 37 degrees C. Binding properties give Kd (19.0 +/- 4.6 nmol/l) and Bmax (approximately 10(6) sites/cell) values in A431 cells overexpressing the CCK2-R. In vivo evaluation of the compound shows rapid and specific targeting to CCK2-R, a fourfold higher accumulation compared to nonreceptor expressing tumors. 相似文献
992.
993.
6‐Mer Hyaluronan Oligosaccharides Modulate Neuroinflammation and α‐Synuclein Expression in Neuron‐Like SH‐SY5Y Cells 下载免费PDF全文
994.
Marco Romano Simone Maganuco Stefania Nosotti Fabio Manucci 《Historical Biology》2016,28(8):1014-1025
Since their initial formal recognition by Richard Owen in 1842, dinosaurs have always stood out in the collective imagination for their size and unusual appearance. Therefore, these marvellous animals are a source of curiosity and wonder for people of all ages, social and cultural backgrounds. Thanks to improved research techniques, palaeontologists have been able to work reconstructing the most plausible appearance of dinosaurs. Starting with petrified bones, they tried to make a dream come true – to bring the planet’s ancient inhabitants back to life. The new Italian exhibition Dinosaurs in the Flesh: Science and Art bring the Rulers of a Lost World Back to Life reveals the marriage of science and art that brings back to life animals that lived tens or hundreds of millions of years ago. Palaeontologists and artists collaborate on reconstructing the appearance of organisms from the distant past through study of the fossils, often with the aid of new technologies. The new project, which takes up the idea of Waterhouse Hawkins and Owen and their legacy to restore these ancient vertebrates based on solid scientific foundations, represents to date the only way to reanimate these fascinating lost animals. 相似文献
995.
G‐CSF contributes at the healing of tunica media of arteriotomy‐injured rat carotids by promoting differentiation of vascular smooth muscle cells 下载免费PDF全文
996.
997.
Serena Pagliarani Sabrina Lucchiari Gianna Ulzi Michela Ripolone Raffaella Violano Francesco Fortunato Andreina Bordoni Stefania Corti Maurizio Moggio Nereo Bresolin Giacomo P. Comi 《生物化学与生物物理学报:疾病的分子基础》2018,1864(10):3407-3417
Glycogen disease type III (GSDIII), a rare incurable autosomal recessive disorder due to glycogen debranching enzyme deficiency, presents with liver, heart and skeletal muscle impairment, hepatomegaly and ketotic hypoglycemia. Muscle weakness usually worsens to fixed myopathy and cardiac involvement may present in about half of the patients during disease. Management relies on careful follow-up of symptoms and diet. No common agreement was reached on sugar restriction and treatment in adulthood.We administered two dietary regimens differing in their protein and carbohydrate content, high-protein (HPD) and high-protein/glucose-free (GFD), to our mouse model of GSDIII, starting at one month of age. Mice were monitored, either by histological, biochemical and molecular analysis and motor functional tests, until 10?months of age.GFD ameliorated muscle performance up to 10?months of age, while HPD showed little improvement only in young mice. In GFD mice, a decreased muscle glycogen content and fiber vacuolization was observed, even in aged animals indicating a protective role of proteins against skeletal muscle degeneration, at least in some districts. Hepatomegaly was reduced by about 20%. Moreover, the long-term administration of GFD did not worsen serum parameters even after eight months of high-protein diet. A decreased phosphofructokinase and pyruvate kinase activities and an increased expression of Krebs cycle and gluconeogenesis genes were seen in the liver of GFD fed mice.Our data show that the concurrent use of proteins and a strictly controlled glucose supply could reduce muscle wasting, and indicate a better metabolic control in mice with a glucose-free/high-protein diet. 相似文献
998.
Alessandra Govoni Delia Gagliardi Giacomo P. Comi Stefania Corti 《Molecular neurobiology》2018,55(8):6307-6318
Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder characterized by the degeneration of lower motor neurons (MNs) in the spinal cord and brain stem, which results in relentless muscle weakness and wasting, leading to premature death due to respiratory complications. The identification of the specific mutations in the survival motor neuron 1 (SMN1) gene that causes SMA has led to the development of experimental therapeutic strategies to increase SMN protein expression, including antisense oligonucleotides, small molecules, and gene therapy, which have so far shown promising results. The timing of therapeutic intervention is crucial since most of the degeneration in MNs occurs in the first months of life in patients with SMA type 1, which is the most severe and common form of SMA. Nevertheless, a precise temporal window for therapeutic intervention has not yet been identified. Evidence from in vivo studies in mice and large animals suggested that early therapeutic intervention for SMA correlated with better motor performance, longer survival, and, occasionally, rescue of the pathological phenotype. Indeed, the need to compensate for the loss of SMN protein function seemed to diminish during adulthood (even though repair ability after nerve injury remained impaired), suggesting the possibility of tapering the therapy administration late in the disease course. Moreover, recent clinical trials on children afflicted with SMA type 1 have shown a more rapid achievement of motor milestones and diminished disease severity when therapy was administered at an early age and earlier in the disease course. Finally, these results highlight the importance of newborn screening for SMA to facilitate early diagnosis and present the patient with available treatments while they are still in the presymptomatic stage. 相似文献
999.
Maria Carmela Bonaccorsi di Patti Antimo Cutone Fabio Polticelli Luigi Rosa Maria Stefania Lepanto Piera Valenti Giovanni Musci 《Biometals》2018,31(3):399-414
In the last 20 years, several new genes and proteins involved in iron metabolism in eukaryotes, particularly related to pathological states both in animal models and in humans have been identified, and we are now starting to unveil at the molecular level the mechanisms of iron absorption, the regulation of iron transport and the homeostatic balancing processes. In this review, we will briefly outline the general scheme of iron metabolism in humans and then focus our attention on the cellular iron export system formed by the permease ferroportin and the ferroxidase ceruloplasmin. We will finally summarize data on the role of the iron binding protein lactoferrin on the regulation of the ferroportin/ceruloplasmin couple and of other proteins involved in iron homeostasis in inflamed human macrophages. 相似文献
1000.
Francesco Calvani Antimo Cutone Maria Stefania Lepanto Luigi Rosa Valentino Valentini Piera Valenti 《Biometals》2018,31(3):445-455
Osteonecrosis of the jaws is an emerging pathological condition characterized by un-exposure or exposure of the necrotic bone, independently from the etiology. This term is usually referred to medication-related osteonecrosis of the jaws due to severe adverse reaction to certain medicines, as bisphosphonates, used for the treatment of cancer and osteoporosis. The management of patients with Bisphosphonate-Related Osteonecrosis of the Jaws (BRONJ) remains challenging because surgical and medical interventions may not eradicate this pathology. The goal of treatment of patients at risk of developing BRONJ or of those who have active disease is the preservation of quality of life by controlling pain, managing infection, and preventing the development of new areas of necrosis. The treatment of osteonecrosis consists in the surgical removal of necrotic bone followed by antibiotic therapy and application of sterile greasy gauze until the wound closure. The classical medical treatment has been compared with the innovative one consisting in the application of sterile greasy gauze soaked with bovine lactoferrin (bLf) after surgery. Here, for the first time, bLf efficacy on wound repair in subjects suffering from BRONJ with the progressive destruction of bone in the mandible or maxilla has been demonstrated. The positive results consist in a significant shorter time of wound closure (1 or 2 weeks) compared to that observed with classical surgical treatment (2–3 months). These promising results are an interesting tool for the innovative treatment of this pathology and for increasing the quality of life of these patients. 相似文献