Interactions from lipid membrane deformations

Biological cells, the basic building blocks of all life forms, are surrounded by a lipid membrane. More than half of the membrane is occupied by membrane proteins, which can regulate the cell functionality through specific arrangements. To regulate the arrangements several proteins have to work together. In addition to direct forces, there exists an indirect force between the proteins, which stems from their deformation of the membrane and contributes to their self-organization. Since the actual membrane is very crowded and proteins are too tiny and complex to measure this interaction, in this thesis we used a model system consisting of lipid membranes and solid particles to study the deformation-mediated interaction. We experimentally confirmed for the first time that, unlike many known forces, this deformation-mediated interaction is not additive, i.e. the strength and range of three (or more) deformations cannot be obtained by simple addition of the interactions between pairs of deformations. We found that the interaction weakens with increasing number of membrane-deforming particles and that the particle become less ordered. We investigated deformations in both directions of the membrane and found that the interaction can be both repulsive and attractive, and furthermore depends on the shape of the deformation. This thesis helps to better understand the organization of proteins that deform cellular membranes. The work described in this thesis was financed by the physics department at Leiden UniversityBiological and Soft Matter Physic

Antibacterial potential of extracts of leaves of Parrotia persica

Ethanol, methanol, chloroform, petroleum ether and aqueous extracts of leaves of Parrotia persica were evaluated for antibacterial activity. The zone of inhibition varied from 13 to 22 mm. The highest inhibittionwas obtained with methanol and ethanol. Chloroform and petroleum ether extracts did not show any activity. The minimal inhibitory concentration (MIC) value of the methanol extract for the test bacteria ranged between 3.12 and 6.25 mg/ml and that of ethanol extract ranged between 6.25 and 12.5 mg/ml. The results scientifically validate the use of this plant in the traditional medicine of Iran

Effects of the Dietary Approaches to Stop Hypertension (DASH) Eating Plan on Cardiovascular Risks Among Type 2 Diabetic Patients: A randomized crossover clinical trial

Objective: To determine the effects of the Dietary Approaches to Stop Hypertension (DASH) eating pattern on cardiometabolic risks in type 2 diabetic patients. Research design and methods: A randomized crossover clinical trial was undertaken in 31 type 2 diabetic patients. For 8 weeks, participants were randomly assigned to a control diet or the DASH eating pattern. Results: After following the DASH eating pattern, body weight (P = 0.007) and waist circumference (P = 0.002) reduced significantly. Fasting blood glucose levels and A1C decreased after adoption of the DASH diet (−29.4 ± 6.3 mg/dl; P = 0.04 and −1.7 ± 0.1%; P = 0.04, respectively). After the DASH diet, the mean change for HDL cholesterol levels was higher (4.3 ± 0.9 mg/dl; P = 0.001) and LDL cholesterol was reduced (−17.2 ± 3.5 mg/dl; P = 0.02). Additionally, DASH had beneficial effects on systolic (−13.6 ± 3.5 vs. −3.1 ± 2.7 mmHg; P = 0.02) and diastolic blood pressure (−9.5 ± 2.6 vs. −0.7 ± 3.3 mmHg; P = 0.04). Conclusions: Among diabetic patients, the DASH diet had beneficial effects on cardiometabolic risks

Atorvastatin treatment softens human red blood cells: An optical tweezers study

Optical tweezers are proven indispensable single-cell micro-manipulation and mechanical phenotyping tools. In this study, we have used optical tweezers for measuring the viscoelastic properties of human red blood cells (RBCs). Comparison of the viscoelastic features of the healthy fresh and atorvastatin treated cells revealed that the drug softens the cells. Using a simple modeling approach, we proposed a molecular model that explains the drug-induced softening of the RBC membrane. Our results suggest that direct interactions between the drug and cytoskeletal components underlie the drug-induced softening of the cells. © 2018 Optical Society of America

Legal Protection of the Environment in Armed Conflicts with Emphasis on the Second Gulf war

ABSTRACT The international community has passed terrible ordeals in the course of wars and, due to the stability of environmental damages of war, the protection of the environment has proved to be of high necessity for the international community. As a geopolitically important maritime region, the Persian Gulf, due to massive energy resources, is no exception to this trend and is under the supervision of the international law of armed conflicts. Today, since the necessity of environmental protection in times of armed conflicts has had marked effects on promoting the status of the wartime environmental protection, its norms can be viewed as customary international law and jus cogens with erga omnes effects. Considering environmental concerns in times of war and peace is thus accounted to be an international requirement, particularly for the belligerent parties in armed conflicts. Accordingly, regarding the strategic status of the Persian Gulf and the previous experiences of two wars in the region, the Second Gulf War (1990War ( -1991 and its environmental effects in particular, and by evaluating the existing regulations in the course of the Second War, the present study attempts to reach a new legal approach according to which, in case of the outbreak of another war in the region or in any spot in the world, environmental damages caused by armed conflicts be kept to a minimum

Dairy food products: good or bad for cardiometabolic disease?

Prevalence of type 2 diabetes mellitus (T2DM) is rapidly increasingly and is a key risk for CVD development, now recognised as the leading cause of death globally. Dietary strategies to reduce CVD development include reduction of saturated fat intake. Milk and dairy products are the largest contributors to dietary saturated fats in the UK and reduced consumption is often recommended as a strategy for risk reduction. However, overall evidence from prospective cohort studies does not confirm a detrimental association between dairy product consumption and CVD risk. The present review critically evaluates the current evidence on the association between milk and dairy products and risk of CVD, T2DM and the metabolic syndrome (collectively, cardiometabolic disease). The effects of total and individual dairy foods on cardiometabolic risk factors and new information on the effects of the food matrix on reducing fat digestion are also reviewed. It is concluded that a policy to lower SFA intake by reducing dairy food consumption to reduce cardiometabolic disease risk is likely to have limited or possibly negative effects. There remain many uncertainties, including differential effects of different dairy products and those of differing fat content. Focused and suitably designed and powered studies are needed to provide clearer evidence not only of the mechanisms involved, but how they may be beneficially influenced during milk production and processing

Atorvastatin treatment softens human red blood cells: An optical tweezers study

Optical tweezers are proven indispensable single-cell micro-manipulation and mechanical phenotyping tools. In this study, we have used optical tweezers for measuring the viscoelastic properties of human red blood cells (RBCs). Comparison of the viscoelastic features of the healthy fresh and atorvastatin treated cells revealed that the drug softens the cells. Using a simple modeling approach, we proposed a molecular model that explains the drug-induced softening of the RBC membrane. Our results suggest that direct interactions between the drug and cytoskeletal components underlie the drug-induced softening of the cells. © 2018 Optical Society of America

Meta-analysis: COVID-19 diagnosis in chest CT�master key for radiologists

Background: COVID-19 was discovered in February in China. Due to the high prevalence of the disease, early detection and rapid isolation of patients are the vital points for controlling the outbreak. The purpose of this study was to determine the correct location of chest CT scan in the diagnosis of COVID-19. Main text: The current study is a systematic review and meta-analysis. 2959 papers were found in all national and international databases. The study has been reported based on the PRISMA checklist. All analyses were done by CMA Ver. 2 software. The statistical analysis results show that the GGO observation level in the available shape was 46 in CT scan results, and the consolidation observation level in the general form was 33 in CT scan results. Pleural effusion was 7, and linear opacity observation level was 24 in CT scan results in the general form. The CT scan test sensitivity level was gained 94.7, and PCR test sensitivity level was achieved as 94.8. This level was 89 in the early stage. Conclusion: The chest CT has about 24 higher diagnostic sensitivity than the PCR test, in the early stage. GGO revealed a declining process and also indicates that GGO is an early symptom of the disease in CT scan. Linear opacity is the reason behind the initial dyspnea in coronavirus suffering patients referring to the medical centers. The extra-pulmonary lesions increase in the last stage of the disease that makes the patient�s worse. © 2021, The Author(s)