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This paper is concerned with the Dirichlet problem for an equation involving the 1–Laplacian operator Δ1u:=div(Du|Du|) and having a singular term of the type f(x)uγ. Here f∈LN(Ω) is nonnegative, 0<γ⩽1 and Ω is an open bounded set with Lipschitz‐continuous boundary. We prove an existence result for a concept of solution conveniently defined. The solution is obtained as limit of solutions to p‐Laplacian type problems. Moreover, when f(x)>0 almost everywhere, the solution satisfies those features that might be expected as well as a uniqueness result. We also give explicit one–dimensional examples that show that, in general, uniqueness does not hold. We remark that the Anzellotti theory of L∞–divergence–measure vector fields must be extended to deal with this equation. [ABSTRACT FROM AUTHOR]

We prove the existence of solutions of nonlinear elliptic equations with first-order terms having “natural growth” with respect to the gradient. The assumptions on the source terms lead to the existence of possibly unbounded solutions (though with exponential integrability). The domain Ω is allowed to have infinite Lebesgue measure. [ABSTRACT FROM AUTHOR]

Phytotherapy has long been a source of medicinal products and over the years there have been many attempts to use herbal medicines for the treatment of diabetes. Several medicinal plants and their preparations have been demonstrated to act at key points of glucidic metabolism. The most common mechanisms of action found include the inhibition of α-glucosidase and of AGE formation, the increase of GLUT-4 and PPARs expression and antioxidant activity. Despite the large amount of literature available, the actual clinical effectiveness of medicinal plants in controlling diabetes-related symptoms remains controversial and there is a crucial need for stronger evidence-based data. In this review, an overview of the medicinal plants, which use in the management of diabetes is supported by authoritative monographs, is provided. References to some species which are currently under increasing clinical investigation are also reported., Competing Interests: The authors declare no conflict of interest.

Benign prostatic hyperplasia is a common disease in men aged over 50 years old, with an incidence increasing to more than 80% over the age of 70, that is increasingly going to attract pharmaceutical interest. Within conventional therapies, such as α -adrenoreceptor antagonists and 5 α -reductase inhibitor, there is a large requirement for treatments with less adverse events on, e.g., blood pressure and sexual function: phytotherapy may be the right way to fill this need. Serenoa repens standardized extract has been widely studied and its ability to reduce lower urinary tract symptoms related to benign prostatic hyperplasia is comprehensively described in literature. An innovative investigation on the mechanism of inhibition of 5 α -reductase by Serenoa repens extract active principles is proposed in this work through computational methods, performing molecular docking simulations on the crystal structure of human liver 5 β -reductase. The results confirm that both sterols and fatty acids can play a role in the inhibition of the enzyme, thus, suggesting a competitive mechanism of inhibition. This work proposes a further confirmation for the rational use of herbal products in the management of benign prostatic hyperplasia, and suggests computational methods as an innovative, low cost, and non-invasive process for the study of phytocomplex activity toward proteic targets., Competing Interests: The authors declare there are no competing interests.

The Italian herbal products market is the most prosperous in Europe. The proof is represented by the use of these products in several marketing categories, ranging from medicine to nutrition and cosmetics. Market and legislation in Italy are at the same time cause and consequence of this peculiar situation. In fact, the legislation on botanical food supplements in Italy is very permissive and at the same time the market shows an overall satisfaction of users and strong feedback in terms of consumption, which brings a widening use of medicinal plants, formerly the prerogative of pharmaceuticals, to other fields such as nutrition. This review summarizes the market and normative panorama of herbal products in Italy, highlighting the blurred boundaries of health indications, marketing authorizations and quality controls between herbal medicines and non pharmaceutical products, such as food supplements, cosmetics and other herbal-based "parapharmaceuticals"., Competing Interests: The authors declare no conflict of interest.

Hand washing is considered as the single most important strategy to prevent infections. World health organization (WHO) defines hand hygiene as a primary issue of personal care with particular reference to hospital personnel and health facility workers. In this work, we investigated a new combination for hand disinfection as an alternative to alcohol-based and chlorhexidine products. The new combination of 5-pyrrolidone-2-carboxylic acid (PCA) and copper sulphate pentahydrate (CS) was tested upon different bacterial species that normally colonize hands, including Staphylococcus aureus, methicillin resistant S. aureus (MR S. aureus), Staphylococcus epidermidis, multidrug resistant S. epidermidis (MDR S. epidermidis), Streptococcus pyogenes, Streptococcus agalactiae, Escherichia coli, Candida albicans and three clinical isolates: MR S. aureus, MDR S. epidermidis, and an E. coli strain. Minimal inhibitory concentrations (MICs), Minimal bactericidal concentrations (MBCs), fractional inhibitory concentration (FIC) indices, and fractional bactericidal concentration (FBC) indices were evaluated. Ethanol 70% V/V, isopropanol 60% V/V, and 4% w/V chlorhexidine solution were used as reference hand disinfectants. Copper sulphate pentahydrate was very effective against all tested microorganisms: The MIC and MBC for CS ranged from 781 mg/l against S. pyogenes to 12500 mg/l against E. coli strains and C. albicans. In addition, PCA exhibited a good antimicrobial activity, in particular, against S. pyogenes and S. agalactiae. The combination of CS and PCA showed a strong synergistic effect and all FIC indices were ≤0·500. The combination of CS and PCA were more effective than ethanol 70% V/V and isopropanol 60% V/V. In addition to antimicrobial activity, the new formulation possesses peculiar features such as residual activity and moisturizing effect. This work identifies a new strategy for hand disinfection.

The relevance of H. pylori to the pathogenesis of gastritis and gastroduodenal ulcers has been proposed for about the past 25 years; the presence of this bacterium is now established as the main risk factor in the development of stomach carcinomas and lymphomas. Antibiotic treatment does not always inhibit or kill H. pylori because of the potential side effects of antibiotic resistance. Previous research has indicated that red wines have therapeutic benefits against this bacterium. The purpose of our study was to determine the potential of Italian red wines to inhibit H. pylori in a laboratory medium and to compare their antimicrobial activity with that of red grape juice and with isolated procyanidins. The antiradical capacity of Italian red wines was also determined. In conclusion, a novel approach is offered coupling antioxidant benefits of red wines with synergistic effectiveness.

Sedum telephium ssp. maximum is a medicinal plant that possesses anti-inflammatory, analgesic and keratolytic properties. We investigated the anti-inflammatory activity of its methanolic extract (STME) in rat peritoneal macrophages (MPhis) stimulated with lipopolysaccharide from Salmonella enteritidis. After stimulation with 10 microg/ml of LPS, MPhis were coincubated with different doses of STME (8, 16 and 32 microg/ml) or RPMI medium alone using different times of incubation. STME reduced levels of tumor necrosis factor-alpha, both mRNA and its protein, and significantly decreased IL-1beta and IL-6 production. Moreover, STME inhibited inducible nitric oxide synthase expression and blunted nitrite release and inhibited both extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase activation in lipopolysaccharide-stimulated MPhis. Data show that STME might be useful as a potential anti-inflammatory agent., (Copyright 2008 S. Karger AG, Basel.)

Clinical studies have demonstrated that the antidepressant efficacy of Hypericum perforatum extract is comparable to that of classic antidepressants, such as imipramine. The role played by its components, particularly hypericin and hyperforin, has been examined in different experimental models of depression. The present study was carried out in order to verify the hypothesis that hyperforin is the main active antidepressant component. For this purpose we evaluated the activity of a dry extract from a subspecies of H. perforatum, H. perforatum spp. angustifolium, which has a higher hyperforin content than H. perforatum perforatum, in a series of experimental models of depression. The models used are based on the development of hyporeactivity to aversive stimuli induced by unavoidable stress exposure in rats. The extract of H. perforatum angustifolium presented an efficacy that was similar to that obtained with a treatment with imipramine or H. perforatum perforatum. Furthermore, in the models used the H. perforatum angustifolium extract was active at doses eight times lower than those necessary to produce a comparable activity with H. perforatum extract.

The treatment of non-selected depressed patients with a hydro-alcoholic extract of Hypericum perforatum has been reported to have an efficacy similar to that of classical antidepressants. The effects of H. perforatum on three animal depression models have been studied: (a) an acute form of escape deficit (ED) induced by unavoidable stress; (b) a chronic model of ED, which can be maintained by the administration of mild stressors on alternate days; (c) a model of anhedonia based on the finding that repeated stressors prevent the development of appetitive behavior induced by vanilla sugar in satiated rats fed ad libitum. H. perforatum: (i) acutely protects animals from the sequelae of unavoidable stress; (ii) reverts the chronic escape deficit state maintained by repeated stressors and (iii) preserves the animal's capacity to acquire motivated appetitive behavior. Exposure to chronic stress not only induces escape deficit, but also decreases extraneuronal levels of dopamine in the nucleus accumbens shell; both behavioral and neurochemical effects are reverted by long-term treatment with antidepressants. Three-week treatment with H. perforatum reverted the chronic stress effect on extraneuronal dopamine in the nucleus accumbens. A consistent body of data in the literature suggests that, among the components of H. perforatum extract, hyperforin is the compound (or one of the compounds) responsible for the antidepressant activity. We compared the efficacy of the total extract with the efficacy of hyperforin after p.o. administration. In the acute-escape deficit model, hyperforin showed a potency of about ten times that of the total extract in protecting rats from the sequelae of unavoidable stress. Thus, hyperforin appears to be the most likely active component responsible for the antidepressant activity of H. perforatum.

The apparent current explosion of interest and commercial activity in the area of herbal products should be followed by accurate quality control. In this work, the authors carried out the specific quality assays of all the aromatic drugs reported in European Pharmacopoeia. For each drug, several samples of different brands were bought in pharmacies, herbalist's shops, or supermarkets. The worst results were obtained in the assay for the essential oil content and this is very negative as the medicinal activities of these drugs are ascribed to their essential oil content. The samples of different brands yielded very different results from a qualitative point of view. In most cases, the analyzed samples were very far from the acceptable qualitative standards that they definitely lacked any health benefits.

The treatment of unselected depressed patients with an hydro-alcoholic extract of Hypericum perforatum has been reported to have an efficacy similar to that of classical antidepressants. In the present report, the effects of H. perforatum were studied on three animal models of depression: (i) an acute form of escape deficit (ED) induced by an unavoidable stress; (ii) a chronic model of ED, which can be maintained by the administration of mild stressors on alternate days; (iii) a model of anhedonia based on the finding that repeated stressors prevent the development of an appetitive behavior induced by vanilla sugar in satiated rats fed ad libitum. H. perforatum acutely protected animals from the sequelae of unavoidable stress; such an effect was partially prevented by the administration of SCH 23390 or (-)-pindolol. Moreover, H. perforatum reverted the ED maintained by repeated stressors and preserved the animal's capacity to learn to operate for earning a positive reinforcer. It was concluded that H. perforatum contains some active principle(s) endowed with antidepressant activity.

A study was performed in order to examine the effect of 4-Aminopyridine on gastric secretion of the rat. Acid secretion was evaluated in the stomach perfused rat preparation in anaesthetized animals. Systemic administration of the drug dose depently stimulated gastric secretion and the threshold dose was not dissimilar to that of Histamine. Atropine sulphate was able to antagonize the stimulating effect of the drug.

Smilax macrophylla Vers., administered per os at the doses of 1 or 2 g/kg in normal rats or in rats made hyperuricemic and hyperuricosuric by potassium oxonate (250 mg/Kg p.o.) or fructose (4 g/Kg p.o.) does not modify diuresis, but increases the excretion of uric acid and allantoin in normal rats and in those pretreated with fructose, whereas it is inactive in oxonate pretreated rats. Allantoinemia is not modified by fructose or oxonate, whereas uricemia is modified.