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SYNTHESIS OF PYRROLO[3,2-H]QUINOLINONES WITH GOOD PHOTOCHEMOTHERAPEUTIC ACTIVITY AND NO DNA DAMAGE
2010
In the search for new photochemotherapeutic agents, a series of derivatives of the ring system pyrrolo[3,2-h]quinoline--bioisosters of the angular furocoumarin angelicin--were synthesized through a four-step synthetic approach, in reasonable overall yields. Eight of the synthesized derivatives showed a remarkable phototoxicity against a panel of four human tumor cell lines and a great dose UV-A dependence, reaching IC₅₀ values at submicromolar level. The mode of cellular death photoinduced by pyrrolo[3,2-h]quinolines was evaluated through a series of flow cytometric analysis and other tests were performed to clarify their mechanism of action.
Hypothesis: can N-acetylcysteine be beneficial in Parkinson's disease?
1999
Based on the finding of decreased mitochondrial complex I activity in the substantia nigra of patients with Parkinson's disease, we propose that the consequent reduction of ATP synthesis and increased generation of reactive oxygen species may be a possible cause of nigrostriatal cell death. Since sulfhydryl groups are essential in oxidative phosphorylation, thiolic antioxidants may contribute to the preservation of these proteins against oxidative damage. In the present paper, we hypothesize that treatment with a sulfur-containing antioxidant such as N-acetylcysteine may provide a new neuroprotective therapeutic strategy for Parkinson's disease.
Sicilia e Grecia La conservazione dei monumenti alla fine del Settecento
2015
Fin dalla seconda metà del Settecento in Sicilia si inizia a tutelare, e dunque conservare, i monumenti dell’epoca classica della città di Taormina e perfino un gruppo di alberi secolari, chiamati il “castagno dei cento cavalli”. Inoltre, nel 1778, il governo borbonico istituì, per tutti i monumenti antichi della Sicilia, una commissione formata dai “Regi custodi” – sopraintendenti delle antichità, da un architetto esperto di monumenti antichi, da un pittore di vedute e da un capo mastro, per studiare e rilevare lo stato di conservazione dei monumenti stessi. A seguito di queste indagini, nel 1780, furono approntati i primi interventi di restauro nel tempio di Segesta e in alcuni templi di …
Extracellular calcium-sensing receptor mediates human bronchial epithelial wound repair
2010
The airway epithelium routinely undergoes damage that requires repair to restore epithelial barrier integrity. Cell migration followed by proliferation are necessary steps to achieve epithelial repair. Calcium-sensing receptor (CaSR) is implicated in cell migration and proliferation processes. Thus we hypothesized that CaSR mediates lung epithelial wound repair. We detected CaSR expression in human lung and in well-differentiated human bronchial epithelial cells (HBEC). To test the CaSR functionality, HBEC loaded with fura-2 were stimulated with extracellular Ca(2+) ([Ca(2+)](out)) which resulted in a concentration-dependent intracellular Ca(2+) ([Ca(2+)](i)) increase (potency approximately…
Exogenous ochronosis and striae atrophicae following the use of bleaching creams.
2005
Exogenous ochronosis is a paradoxical hyper-pigmentation of the skin caused by the long-term use of hydroquinone-containing bleaching creams. Ochronosis is an uncommon condition characterized by yellow-brown pigmented deposits in the dermis. We report two cases of exogenous ochronosis in two female patients of the sub-Saharan African population. The lesions were characterized by an asymptomatic hyper-pigmentation of the face with gradually progressive blue-black macular patches, and in case no. 2, in addition to dyschromic lesions, striae atrophicae were present. This phenomenon is the outcome of the use of skin care products containing high concentrations of hydroquinone- and glucocorticoi…
In vitro cytotoxicity of patulin, deoxynivalenol, nivalenol and zearalenone on CHO-K1 cells
2006
Ocular Motor Paroxysmal Events in Neonates and Infants: A Review of the Literature
2021
Abstract Background Ocular paroxysmal events can accompany a variety of neurological disorders. Particularly in infants, ocular paroxysmal events often represent a diagnostic challenge. Distinguishing between epileptic and nonepileptic events or between physiological and pathologic paroxysmal events can be challenging at this age because the clinical evaluation and physical examination are often limited. Continuous polygraphic video-electroencephalography (EEG) monitoring can be helpful in these situations. Methods We review ocular paroxysmal events in newborns and infants. The aim is to improve clinical recognition of ocular paroxysmal events and provide a guide to further management. Usin…
Induction of micronuclei in V79 Chinese hamster cells by tetrachlorohydroquinone, a metabolite of pentachlorophenol
1992
Tetrachlorohydroquinone, a metabolite of the fungicide pentachlorophenol, induced significant dose-related increases in micronuclei in V79 Chinese hamster cells without exogenous metabolic activation. The lowest observed effective dose was 10 microM, where the relative survival was about 62%. At the highest dose tested, 20 microM, the relative survival was about 8% and the frequency of cells with micronuclei was about 6 times the solvent control frequency. The induction of micronuclei by tetrachlorohydroquinone was significantly inhibited by the hydroxyl radical scavenger dimethyl sulfoxide at 5% (v/v).
Cytotoxic and protein kinase inhibiting nakijiquinones and nakijiquinols from the sponge Dactylospongia metachromia.
2014
Chemical investigation of the sponge Dactylospongia metachromia afforded five new sesquiterpene aminoquinones (1-5), two new sesquiterpene benzoxazoles (6 and 7), the known analogue 18-hydroxy-5-epi-hyrtiophenol (8), and a known glycerolipid. The structures of all compounds were unambiguously elucidated by one- and two-dimensional NMR and by MS analyses, as well as by comparison with the literature. Compounds 1-5 showed potent cytotoxicity against the mouse lymphoma cell line L5178Y with IC50 values ranging from 1.1 to 3.7 μM. When tested in vitro for their inhibitory potential against 16 different protein kinases, compounds 5, 6, and 8 exhibited the strongest inhibitory activity against AL…
Traditional Chinese Medicine Remedy to Jury: The Pharmacological Basis for the Use of Shikonin as an Anticancer Therapy
2013
Shikonin is the major constituent of the root of Lithospermum erythrorhizon, which has been used in traditional Chinese medicine to treat external wounds, burns, or dermatitis for centuries. Nowadays, this root is commonly used as an herbal medicine against cancer. Studies carried out over the past 30 years have demonstrated that many of the effects historically associated with the use of this root have a scientific basis, with shikonin and its derivatives being responsible for its pharmacological properties. These include both anti-inflammatory and anticancer effects. While previous summaries have focused on the pharmacokinetics and toxicity of shikonin, the aim of this review is to report…