58 research outputs found

    A Field Guide to Pandemic, Epidemic and Sporadic Clones of Methicillin-Resistant Staphylococcus aureus

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    In recent years, methicillin-resistant Staphylococcus aureus (MRSA) have become a truly global challenge. In addition to the long-known healthcare-associated clones, novel strains have also emerged outside of the hospital settings, in the community as well as in livestock. The emergence and spread of virulent clones expressing Panton-Valentine leukocidin (PVL) is an additional cause for concern. In order to provide an overview of pandemic, epidemic and sporadic strains, more than 3,000 clinical and veterinary isolates of MRSA mainly from Germany, the United Kingdom, Ireland, France, Malta, Abu Dhabi, Hong Kong, Australia, Trinidad & Tobago as well as some reference strains from the United States have been genotyped by DNA microarray analysis. This technique allowed the assignment of the MRSA isolates to 34 distinct lineages which can be clearly defined based on non-mobile genes. The results were in accordance with data from multilocus sequence typing. More than 100 different strains were distinguished based on affiliation to these lineages, SCCmec type and the presence or absence of PVL. These strains are described here mainly with regard to clinically relevant antimicrobial resistance- and virulence-associated markers, but also in relation to epidemiology and geographic distribution. The findings of the study show a high level of biodiversity among MRSA, especially among strains harbouring SCCmec IV and V elements. The data also indicate a high rate of genetic recombination in MRSA involving SCC elements, bacteriophages or other mobile genetic elements and large-scale chromosomal replacements

    A Field Guide to Pandemic, Epidemic and Sporadic Clones of Methicillin-Resistant Staphylococcus aureus

    Get PDF
    In recent years, methicillin-resistant Staphylococcus aureus (MRSA) have become a truly global challenge. In addition to the long-known healthcare-associated clones, novel strains have also emerged outside of the hospital settings, in the community as well as in livestock. The emergence and spread of virulent clones expressing Panton-Valentine leukocidin (PVL) is an additional cause for concern. In order to provide an overview of pandemic, epidemic and sporadic strains, more than 3,000 clinical and veterinary isolates of MRSA mainly from Germany, the United Kingdom, Ireland, France, Malta, Abu Dhabi, Hong Kong, Australia, Trinidad & Tobago as well as some reference strains from the United States have been genotyped by DNA microarray analysis. This technique allowed the assignment of the MRSA isolates to 34 distinct lineages which can be clearly defined based on non-mobile genes. The results were in accordance with data from multilocus sequence typing. More than 100 different strains were distinguished based on affiliation to these lineages, SCCmec type and the presence or absence of PVL. These strains are described here mainly with regard to clinically relevant antimicrobial resistance- and virulence-associated markers, but also in relation to epidemiology and geographic distribution. The findings of the study show a high level of biodiversity among MRSA, especially among strains harbouring SCCmec IV and V elements. The data also indicate a high rate of genetic recombination in MRSA involving SCC elements, bacteriophages or other mobile genetic elements and large-scale chromosomal replacements

    An immersive virtual reality mobile platform for self-attachment

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    Psychotherapy is among the most effective techniques for combating mental health issues, and virtual reality is beginning to be explored as a way to enhance the efficacy of various psychotherapeu- tic treatments. In this paper we propose an immersive virtual reality mobile platform for Self-Attachment psychotherapy. Under the Self- Attachment therapeutic framework, the causes of disorders such as chronic anxiety and depression are traced back to the quality of the individual’s attachment with their primary caregiver during child- hood. Our proposed platform aims to assist the user in enhancing their capacities for self-regulation of emotion, by means of earning secure attachment through the experience of positive attachment in- teractions, missed in their childhood. In the virtual environment pro- vided by the platform, the adult-self of the user learns to create and strengthen an affectional and supportive bond with the inner-child. It is hypothesised that by long term potentiation and neuroplasticity, the user gradually develops new neural pathways and matures into an effective secure attachment object for the inner-child, thereby en- abling the self-regulation of emotions

    Hepatoprotective effect of berberine against methotrexate induced liver toxicity in rats

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    Hepatotoxicity is one of the major side effects of methotrexate (MTX), which restricts the clinical use of this drug. Berberine (BBR) is a natural compound with multiple pharmacological activities such as antioxidant, antiapoptotic and anti-inflammatory effects. In this study, the effect of BBR on MTX-induced hepatotoxicity was studied. A total number of 28 male Wistar rats were randomly divided into four experimental groups. Rats were pretreated with BBR orally with dose of 100 mg/kg for 10 consecutive days and MTX (20 mg/kg, intraperitoneally) was administrated on the 9th day. Then on day 11, blood samples were collected to determine serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP). The extracted livers were used for histological examination, biochemical assays and real time PCR studies. Malondialdehyde (MDA), glutathione (GSH), protein carbonyl (PC), nitric oxide (NO) levels, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and myeloperoxidase (MPO) activities were assessed in hepatic tissue. In addition, the expression of SOD and PGx was measured using real-time PCR method in hepatic tissue. Results showed that MTX administration significantly increases AST, ALT and ALP levels (all p < 0.001). It also, increases MDA, PC, NO levels and MPO activity (p < 0.001, p < 0.01, p < 0.05 and p < 0.01 respectively). Moreover, MTX decreases hepatic GSH level, SOD, GPx and CAT activities (all p < 0.001). Pre-treatment with BBR for 10 days prevented some of these changes. Serum levels of AST and ALT decreased (all p < 0.001). Hepatic MDA level decreased (p < 0.001) and GSH level as well as GPx activity increased (p < 0.05 and p < 0.01 respectively). Our results indicated that BBR might be useful for prevention of the hepatotoxicity induced by MTX via ameliorative effects on biochemical and oxidative stress indices. © 2017 Elsevier Masson SA

    Hepatoprotective effect of berberine against methotrexate induced liver toxicity in rats

    No full text
    Hepatotoxicity is one of the major side effects of methotrexate (MTX), which restricts the clinical use of this drug. Berberine (BBR) is a natural compound with multiple pharmacological activities such as antioxidant, antiapoptotic and anti-inflammatory effects. In this study, the effect of BBR on MTX-induced hepatotoxicity was studied. A total number of 28 male Wistar rats were randomly divided into four experimental groups. Rats were pretreated with BBR orally with dose of 100 mg/kg for 10 consecutive days and MTX (20 mg/kg, intraperitoneally) was administrated on the 9th day. Then on day 11, blood samples were collected to determine serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP). The extracted livers were used for histological examination, biochemical assays and real time PCR studies. Malondialdehyde (MDA), glutathione (GSH), protein carbonyl (PC), nitric oxide (NO) levels, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and myeloperoxidase (MPO) activities were assessed in hepatic tissue. In addition, the expression of SOD and PGx was measured using real-time PCR method in hepatic tissue. Results showed that MTX administration significantly increases AST, ALT and ALP levels (all p < 0.001). It also, increases MDA, PC, NO levels and MPO activity (p < 0.001, p < 0.01, p < 0.05 and p < 0.01 respectively). Moreover, MTX decreases hepatic GSH level, SOD, GPx and CAT activities (all p < 0.001). Pre-treatment with BBR for 10 days prevented some of these changes. Serum levels of AST and ALT decreased (all p < 0.001). Hepatic MDA level decreased (p < 0.001) and GSH level as well as GPx activity increased (p < 0.05 and p < 0.01 respectively). Our results indicated that BBR might be useful for prevention of the hepatotoxicity induced by MTX via ameliorative effects on biochemical and oxidative stress indices. © 2017 Elsevier Masson SA

    Protective effect of melatonin in the diabetic rat retina

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    Diabetic retinopathy (DR) is one of the most common and serious microvascular complications of diabetes. The aim of this study was to evaluate the effects of melatonin (MEL) on retinal injury in diabetic rats. In this study, 21 rats were randomly divided into three groups: control, diabetic, and diabetic + MEL. Streptozotocin was used to induce diabetes at a dose of 50 mg/kg, i.p., and blood glucose was measured to choose the diabetic rats for the study. MEL (20 mg/kg) was given orally for 7 weeks in diabetic rats starting 1 week after induction of diabetes. After 8 weeks, the groups were compared in terms of mean scores of fluorescein leakage, using fluorescein angiography. Reactive oxygen species (ROS) and malondialdehyde (MDA) levels were estimated in retina using commercially available assays. Structural changes in retinas were evaluated by light microscopy. Results showed that diabetes significantly increased the mean scores of fluorescein leakage, and MDA and ROS levels compared to control group. Treatment of the diabetic rats with MEL for 7 weeks prevented the alterations induced by diabetes in comparison with the diabetic control group.Based on these findings, it can be concluded that MEL might have beneficial effects in prevention of DR. © 2018 Société Française de Pharmacologie et de Thérapeutiqu

    Beneficial effects of melatonin and atorvastatin on retinopathy in streptozocin-induced diabetic rats

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    Objective: The present study was designed to evaluate the effects of Atorvastatin (ATO) plus melatonin (MEL) on streptozocin-induced diabetic retinopathy (DR) in rats. Method: Diabetes was induced in Wistar rats with an intraperitoneal injection of streptozocin (50 mg/kg). Animals were randomly assigned to one of the following groups (8 rats/group): Control group, Diabetic group, Diabetic + MEL group (20 mg/kg/day), Diabetic + ATO group (10 mg/kg/day), Diabetic + MEL + ATO group (as above). Treatments were started one week after induction of diabetes and continued for 7 weeks. At the end of the experiment, angiography was performed and the rats were killed and retinas were harvested for pathological and molecular ex-aminations. Results: Administration of MEL reduced the fluorescein leakage, MDA and ROS levels compared to diabetic group. Treatment with ATO only reduced ROS levels compared to diabetic group. In addition, administration of ATO plus MEL decreased these indices compared to the diabetic and ATO groups. Histologically, retinal vascular congestion was not observed in the combined ATO and MEL group as compared to the diabetic, ATO, and MEL groups. Conclusion: These data provide evidence for the therapeutic value of MEL in combination with ATO in clinical practice for prevention of DR. © 2020 Bentham Science Publishers

    Pretreatment with melatonin protects against cyclophosphamide-induced oxidative stress and renal damage in mice

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    Cyclophosphamide (CP) is widely used in treatment of different cancers. Nephrotoxicity is one of the dose-limiting side effects of CP. This study was carried out to investigate the effect of melatonin (MEL) on CP-induced nephrotoxicity in mice. In this study, 50 Swiss albino mice (20�25 g) were randomly divided into five groups. Mice were pretreated with MEL intraperitoneally (i.p) in doses of 5, 10 and 20 mg/kg for five consecutive days, and CP (200 mg/kg, i.p) was administrated on the 5th day 1 h after the last dose of MEL. Then on day 6, blood samples were collected to determine serum creatinine (Cr) and blood urea nitrogen (BUN) levels. The kidneys were used for histological examination, biochemical assays and real-time PCR studies. Malondialdehyde (MDA), glutathione (GSH), protein carbonyl (PC), nitric oxide (NO) level, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and myeloperoxidase (MPO) activity were assessed in renal tissue. In addition, the expression of SOD2 and PGx1 was measured using real-time PCR method in renal tissue. Results showed that CP administration significantly increases Cr, BUN, MDA, PC, NO level and MPO activity. It also decreases renal GSH level, SOD, GPx and CAT activity. Pretreatment with MEL (especially 20 mg/kg, i.p.) for 5 days prevented these changes; however, it did not affect the SOD activity. Our results revealed that MEL might be useful for prevention of the nephrotoxicity induced by CP through ameliorative effects on biochemical indices and oxidative stress parameters. © 2017 Société Française de Pharmacologie et de Thérapeutiqu

    Protective effect of melatonin in the diabetic rat retina

    No full text
    Diabetic retinopathy (DR) is one of the most common and serious microvascular complications of diabetes. The aim of this study was to evaluate the effects of melatonin (MEL) on retinal injury in diabetic rats. In this study, 21 rats were randomly divided into three groups: control, diabetic, and diabetic + MEL. Streptozotocin was used to induce diabetes at a dose of 50 mg/kg, i.p., and blood glucose was measured to choose the diabetic rats for the study. MEL (20 mg/kg) was given orally for 7 weeks in diabetic rats starting 1 week after induction of diabetes. After 8 weeks, the groups were compared in terms of mean scores of fluorescein leakage, using fluorescein angiography. Reactive oxygen species (ROS) and malondialdehyde (MDA) levels were estimated in retina using commercially available assays. Structural changes in retinas were evaluated by light microscopy. Results showed that diabetes significantly increased the mean scores of fluorescein leakage, and MDA and ROS levels compared to control group. Treatment of the diabetic rats with MEL for 7 weeks prevented the alterations induced by diabetes in comparison with the diabetic control group.Based on these findings, it can be concluded that MEL might have beneficial effects in prevention of DR. © 2018 Société Française de Pharmacologie et de Thérapeutique

    Gold nanoparticle-induced sonosensitization enhances the antitumor activity of ultrasound in colon tumor-bearing mice

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    Purpose: As a noninvasive and nonionizing radiation, ultrasound can be focused remotely, transferring acoustic energy deep in the body, thereby addressing the penetration depth barrier of the light-based therapies. In cancer therapy, the effectiveness of ultrasound can be enhanced by utilizing nanomaterials that exhibit sonosensitizing properties called as nanosonosensitizers. The gold nanoparticle (AuNP) has been recently presented as a potent nanosonosensitizer with the potential to simultaneously enhance both the thermal and mechanical interactions of ultrasound with the tissue of the human body. Accordingly, this paper attempts to evaluate the in vivo antitumor efficiency of ultrasound in combination with AuNP. Methods: BALB/c mice-bearing CT26 colorectal tumor model was intraperitoneally injected with AuNPs and then subjected to ultrasound irradiation (1 MHz; 2 W/cm2; 10 min) for three sessions. Furthermore, 18FFDG (2-deoxy-2-18Ffluoro-d-glucose) positron-emission tomography (PET) imaging was performed and the radiomic features from different feature categorizes were extracted to quantify the tumors� phenotype. Results: The tumors were dramatically shrunk and the mice appeared healthy over 21 days of study span without the evidence of relapse. The animals treated with AuNP + ultrasound exhibited an obvious decline in tumor metabolic parameters such as standard uptake value (SUV), total lesion glycolysis (TLG), and metabolic tumor volume (MTV) compared to other treatment groups. Conclusion: These findings support the use of AuNP as a potent sonosensitizing agent with the potential to use the thermal and mechanical effects of ultrasound so as to cause damage to the focused tumor site, resulting in an improved antitumor efficacy. © 2018 American Association of Physicists in Medicin
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