Inhomogeneous metallic phase upon disordering a two dimensional Mott insulator

We find that isoelectronic disorder destroys the spectral gap in a Mott-Hubbard insulator in 2D leading, most unexpectedly, to a new metallic phase. This phase is spatially inhomogeneous with metallic behavior coexisting with antiferromagnetic long range order. Even though the Mott gap in the pure system is much larger than antiferromagnetic exchange, the spectral gap is destroyed locally in regions where the disorder potential is high enough to overcome the inter-electron repulsion thereby generating puddles where charge fluctuations are enhanced. With increasing disorder, these puddles expand and concomitantly the states at the Fermi energy get extended leading to a metallic phase. We discuss the implications of our results for experiments.Comment: (4 pages, 5 figures

Damage intensity of gallic acid on prostatic cancer cells lineDu145 by alkaline electrophoresis

زمینه و هدف: سرطان پروستات شایع ترین سرطان در جامعه مردان است. عوامل بسیار زیادی منجر به بروز این بیماری می شود. در عین حال فاکتورهای متعددی به منظور پیشگیری و یا درمان این بیماری شناسایی شده اند. آنتی اکسیدان ها و مخصوصاً ترکیبات پلی فنلی مانند اسید گالیک دارای ظرفیت بالقوه ای از این ویژگی هستند. در این مطالعه با استفاده از تکنیک الکتروفورز قلیایی، اثر اسید گالیک را بر لاین سلول های سرطانی Du145 پروستات مورد مطالعه قرار دادیم. روش بررسی: در این مطالعه تجربی آزمایشگاهی، میزان زیست پذیری سلول های Du145 در مجاورت غلظت های مختلف گالیک اسید، به کمک روش رنگ سنجی تترازولیوم (MTT) اندازه گیری و غلظت مهارکنندگی 50 درصد رشد سلول‌ها (IC50) محاسبه شد. سه غلظت نزدیک به IC50 از داروی اسید گالیک برای 48 ساعت بر سلول های مذکور تیمار شد. پس از انجام الکتروفورز قلیایی تصاویر کامت های ایجاد شده با استفاده از نرم افزار CASP آنالیز شدند. یافته ها: با استفاده از آزمون MTT و بر اساس مدل پروبیت میزان IC50 اسید گالیک برای سلول های Du145 برابر 35 میکرومولار بدست آمد. در آزمون الکتروفورز قلیایی، برای سه غلظت 25،30 و 35 میکرومولار اسیدگالیک، نسبت طول کامت به قطر سلول به ترتیب برابر 1/3±6/7، 2/6±13/8 و 1/2±69/4 بود. نتیجه گیری: گالیک اسید به عنوان یک آنتی اکسیدان قدرتمند در غلظت های نزدیک به IC50 اثر مهاری شدیدی بر رشد سلول های سرطان پروستات (لاین Du145) داشته و با اثر تخریبی بر ژنوم این سلول ها می تواند آپوپتوز را در آنان القاء کند

Protective effect of artichoke (Cynara scolymus) leaf extract against lead toxicity in rat

Context: Artichoke, Cynara scolymus L. (Asteraceae), has many natural antioxidants and multiple pharmacological actions. Recent studies have shown that it has antitoxic activity. Objective: Lead (Pb) is a dangerous environmental toxicant that induces a broad range of dysfunctions in human. This study evaluated the protective effect of the hydroethanolic extract of artichoke against altered biochemical parameters in rats fed with lead-containing diet. Materials and methods: Thirty-two rats were randomly divided into four groups. The first (control) group received standard diet. The second, third and fourth groups received 500 mg lead/kg diet, 500 mg lead/kg diet plus 300 mg/kg b.w. artichoke extract daily, and 500 mg lead/kg diet plus 1 mg vitamin C/100 g b.w. daily for 6 weeks, respectively. Serum lead, lipoprotein profile, ALT (alanine transaminase), AST (aspartate transaminase), ALP (alkaline phosphatase), malondialdehyde (MDA) and liver histopathology assessments were conducted. Results: Serum lead, triglyceride (TG), VLDL, ALT, AST, ALP and MDA levels decreased significantly (p 0.05). Furthermore, the liver histopathology in rats treated with artichoke showed a mild degree of lymphocyte infiltration that was relatively comparable to the control and vitamin C-treated groups. Discussion and conclusion: These results clearly show that the artichoke extract in lead-poisoned rats has suitable chelating properties for the reduction of blood lead levels

Effect of silymarin on liver phoshpatidate phosphohydrolase in hyperlipidemic rats

Previous studies have shown that silymarin, a flavonoid antioxidant, possesses a hypolipidemic effect. The aim of this study was to evaluate the effect of silymarin on liver phoshpatidate phosphohydrolase, total plasma cholesterol, plasma lipoproteins, liver and plasma triglyceride, plasma malondialdehyde, and plasma antioxidant in rats fed with high cholesterol diet enriched with fat. Male rats were fed by standard pellet diet (group I), standard diet accompanied with silymarin (group II), lipogenic diet (containing saturated fat, cholesterol and ethanol) plus silymarin (group III), and only lipogenic diet (group IV). On day 60 of the experiment, liver phosphatidate phosphohydrolase activity, liver triglyceride, plasma lipids, plasma malondialdehyde, and plasma antioxidant levels were measured. Group II showed a significant reduction (20) (p < 0.001) in the liver PAP activity compared to group I. The atherogenic ratio of total cholesterol to high density lipoprotein cholesterol, liver triglyceride, plasma total cholesterol, and triglyceride levels significantly decreased (p < 0.05) due to silymarin treatment in group III compared to group IV. Significant reduction in plasma malondialdehyde (p < 0.05) and significant elevation (p < 0.05) in plasma antioxidant power observed in group III compared to group IV. These results clearly suggested that silymarin can be effective to reducing liver phosphatidate phosphohydrolase activity and liver triglyceride. Furthermore, silymarin had blood lipid-reducing and beneficial antioxidant effects in hyperlipidemic diets. © ISISnet Publishers

Biochemical components of Berberis lycium fruit and its effects on lipid profile in diabetic rats

Introduction: Diabetes mellitus is characterized by chronic hyperglycemia with disturbances of carbohydrate, fat, and lipid metabolism resulting from defect in insulin secretion, insulin action, or both. It not only leads to hyperglycemia but also may cause hyperlipidemia. Herbal medicines have always been considered as a healthy source of life. Although medicinal herbs and their derivatives have long been used for hyperlipidemia, their definite effects have not yet been proven by valid research. The aim of this study was to measure minerals in B. lycium fruit and to evaluate the effects of its ethanolic extract on lipid profile in diabetic rats. Methods: For this study 40 male Wistar rats were used and were divided into five equal groups. For induction of diabetes in animals, alloxan monohydrate was used. The animals were under treatment for 42 days. For healthy and diabetic control groups distilled water, for positive diabetic control metformin, for the fourth and fifth diabetic groups Berberis lycium extract in respectively 200 and 600 mg/kg dose were used, daily. Blood samples were collected from heart and lipid profile was measured with autoanalyzer and HPLC. Results: The results of the study indicated that iron level in Berberis lycium fruit was considerably high. In diabetic rats administered with Berberis lycium fruit extract in 600 mg/kg dose, the lipid profile decreased significantly (p&lt;0.05). Conclusion: The present investigation showed that the Berberis lycium fruit extract alleviates lipid profile level and might be used efficiently in hyperlipidemia, especially in diabetic patients. It may also be beneficial in iron deficiency.</p

The neuroprotective effect of pretreatment with Lavandula officinalis ethanolic extract on brain edema in rat stroke model

To evaluate the protective effect of Lavandula officinalis (L. officinalis) extract against blood-brain barrier (BBB) permeability and its possible mechanisms in an experimental model of stroke. METHODS: Focal cerebral ischemia was induced by the transient occlusion of the middle cerebral artery for 1 h in rats. Lavender extract (100, 200 mg/kg i.p.) was injected for 20 consecutive days. BBB permeability and oxidative stress biomarkers were evaluated using standard methods. RESULTS: The results of this study showed that L. officinalis ethanolic extract significantly reduced the BBB permeability in experimental groups when compared with ischemia group. The lavender extract significantly reduced malondialdehyde levels of plasma and brain tissue in intact group when compared with control group. CONCLUSIONS: L. officinalis extract reduced blood brain barrier permeability and alleviated neurological function in rats, and the mechanism may be related to augmentation in endogenous antioxidant defense and inhibition of oxidative stress in the rat brain

Metabolic effects of berberine on liver phosphatidate phosphohydrolase in rats fed on high lipogenic diet: An additional mechanism for the hypolipidemic effects of berberine

Objective: To evaluate the effects of berberine (BBR) on the liver phosphatidate phosphohydrolase (PAP) and plasma lipids in rats fed on high lipogenic and normal diet. Methods: Forty rats were randomly divided into 5 groups. Group I (control) received standard diet. Group II received standard diet plus 90 mg/kg BBR and Groups IV received lipogenic diet (containing sunflower oil, cholesterol and ethanol) without treatment. Groups III and V received lipogenic diet plus 90 mg/kg BBR and 30 mg/kg gemfibrozil, respectively. On Day 60 of the experiment, blood samples were collected and PAP, total cholesterol, triglyceride, low density lipoprotein cholesterol, high density lipoprotein cholesterol, very low density lipoprotein, malondialdehyde, plasma antioxidant, and liver histopathology assessments were conducted. Results: PAP, plasma triglyceride, total cholesterol, very low density lipoprotein, and malondialdehyde levels decreased significantly (P < 0.05) in Group III compared to Group IV (24 94, 36 11, 21 18, 36.86 and 19 59, respectively). The liver triglyceride and cholesterol in Groups III and V had a remarkable decrease (P < 0.001) compared with Group IV (24.94 and 49.13, respectively). There was a significant reduction (P < 0.05) in atherogenic index in Groups III compared with Group IV. Conclusions: These results clearly suggested that BBR could be effective in reducing liver PAP, lipid abnormality, liver triglyceride and lateral side effects of hyperlipidemia. © 2014 by the Asian Pacific Journal of Tropical Biomedicine

The effect of carvacrol on the interleukin-6 gene expression and cell signaling proteins in prostatic cancer cell line DU-145

زمینه و هدف: اینترلوکین-6 باعث ایجاد خاصیت آنتی آپوپتوزی و مقاومت دارویی در سلول های سرطانی پروستات می شود. هدف از این مطالعه بررسی اثر کارواکرول بر بیان ژن IL-6، پروتئین های سیگنالی آن و توانایی مهاجرت در رده سلول های سرطان پروستات (DU-145) می باشد. روش بررسی: در این مطالعه تجربی آزمایشگاهی، سلول های DU-145 با غلظت های مختلف کارواکرول به مدت 48 ساعت تیمار شدند. سپس، درصد زیست پذیری سلول ها به کمک روش رنگ سنجی تترازولیوم (MTT) اندازه گیری و غلظت مهارکنندگی 50 درصد رشد سلول‌ها (IC50) محاسبه شد. میزان IL-6 در غلظت های مختلف کارواکرول با استفاده از کیت الایزا تعیین شد. بیان ژن IL-6 و پروتئین های سیگنالی آن (pStat3، pErk و pAkt) به ترتیب با استفاده از روش های Real time RT PCR و Western blot تعیین شدند. توانایی مهاجرت و تهاجم سلول های DU-145 با استفاده از تست Invasion بررسی شد. یافته ها: میزان IC50 کارواکرول معادل Mµ2/406 به دست آمد. کارواکرول در غلظت Mµ150 باعث افزایش بیان mRNA مربوط به IL-6 وافزایش سنتز پروتئین آن گردید؛ اما در غلظت های بالاتر از Mµ150 بیان mRNA و سنتز IL-6 به صورت وابسته به دوز کاهش یافت (05/0>P). کارواکرول در غلظت بالاتر از Mµ150 بصورت وابسته به دوز باعث کاهش پروتئین های مسیرهای سیگنالی داخل سلولی pStat3، pErk و pAkt شد؛ همچنین، کارواکرول توانایی تهاجم و زیست پذیری سلول های سرطانی DU-145 پروستات را به طور معنی داری کاهش داد (05/0>P). نتیجه گیری: کارواکرول از طریق کاهش پروتئین های مسیرهای سیگنالی داخل سلولی و بیان ژن IL-6 باعث کاهش رشد، تکثیر و توانایی مهاجرت سلولی و باعث القاء آپوپتوز در سلول های سرطان پروستات (DU-145) می گردد. بنابراین، کاواکرول به عنوان یک ماده درمانی سودمند در درمان سرطان پروستات می تواند مورد توجه قرار گیرد