Prognosticating the effect of temperature and pH parameters on size and stability of the nanoliposome system based on thermodynamic modeling.

The main challenge of using nanoliposome systems is controlling their size and stability. In order to overcome this challenge, according to the research conducted at the Research Centre for New Technologies of Biological Engineering, University of Tehran, a model for predicting the size and stability of nanoliposome systems based on thermodynamic relations has been presented. In this model, by using the presented equations and without performing many experiments in the laboratory environment, the effect of temperature, ionic power and different pH can be considered simultaneously whereas examining the components of size, stability and any feature were considered before. Synthesis and application of liposomal nanocarriers in different operating conditions can be investigated and predicted, and due to the change in temperature and pH, the smallest size of th system can be obtained. In this study, we were able to model the synthesis and storage conditions of liposomal nanocarriers at different temperatures and acidic, neutral and alkaline pHs, based on the calculation of mathematical equations. This model also indicates that with increasing temperature, the radius increases but with increasing pH, the radius first increases and then decreases. Therefore, this model can be used to predict size and stability in different operating conditions. In fact, with this modelling method, there is no need to study through laboratory methods and analysis to determine the size, stability and surface loads, and in terms of Accuracy, time and cost savings are affordable.

Revision and Implementation of "Clinical Guideline for Tuberculosis and HIV in Prisons", Great Tehran Prison, Iran.

AIM: To evaluate the feasibility of the revised "Clinical Guideline for HIV and TB" in the Great Tehran Prison during October 2013 to June 2014. METHODS: The guideline includes all aspects of HIV/TB diagnosis based on active case finding (ACF), treatment and care services. Before the implementation, a focus group discussion was conducted, and attended by experts on prison health. The objective was to identify defects and limitations of the guideline. After the discussion, the guideline was revised. The Great Tehran Prison contains three separate units; all prisoners are taken first to "reception and identification unit (quarantine)" and then send to two housing units according to their legal status. An HIV ACF strategy was employed in the quarantine, and two units through a voluntary provider-initiated HIV testing. Three staff of the triangular clinic trained the prisoners about common routes of HIV transmission and the symptoms of TB in the units. In the quarantine, all prisoners were examined for all HIV-risk factors, HIV testing and symptoms of TB. In unit one, healthcare staff continued the ACF process, while in unit two, the peers of prisoners were assigned as the healthcare communicators to proceed with the strategy. At this caring process, when the test result was positive, then the process of care, treatment and follow ups was initiated. Moreover, the use of directly observed therapy (DOT) for antiretroviral therapy (ART) and TB was applied to the sick prisoners. There was also a follow-up caring for released prisoner to refer them to care and treatment services outside the prison. RESULTS: The guideline was implemented in the prison successfully. CONCLUSION: Regarding feasibility of the guideline, the investigators of this study suggest that the guideline should be implemented in other prisons across the country.

In Vitro Co-Delivery Evaluation of Novel Pegylated Nano-Liposomal Herbal Drugs of Silibinin and Glycyrrhizic Acid (Nano-Phytosome) to Hepatocellular Carcinoma Cells.

OBJECTIVE: This study aimed to evaluate a co-encapsulated pegylated nano-liposome system based on two herbal anti-tumor drugs, silibinin and glycyrrhizic acid, for delivery to a hepatocellular carcinoma (HCC) cell line (HepG2). MATERIALS AND METHODS: In this experimental study, co-encapsulated nano-liposomes by the thin layer film hydration method with HEPES buffer and sonication at 60% amplitude. Liposomes that co-encapsulated silibinin and glycyrrhizic acid were prepared with a specified molar ratio of dipalmitoylphosphatidylcholine (DPPC), cholesterol (CHOL), and methoxy-polyethylene glycol 2000 (PEG2000)-derived distearoyl phosphatidylethanolamine (mPEG2000-DSPE). We used the MTT technique to assess cytotoxicity for various concentrations of co-encapsulated nano-liposomes, free silibinin (25% w/v) and glycyrrhizic acid (75% w/v) on HepG2 and fibroblast cell lines over a 48-hour period. RESULTS: Formulation of pegylated nano-liposomes showed a narrow size distribution with an average diameter of 46.3 nm. The encapsulation efficiency (EE) for silibinin was 24.37%, whereas for glycyrrhizic acid it was 68.78%. Results of in vitro cytotoxicity showed significantly greater co-encapsulated nano-liposomes on the HepG2 cell line compared to the fibroblast cell line. The half maximal inhibitory concentration (IC50) for co-encapsulated pegylated nanoliposomal herbal drugs was 48.68 µg/ml and free silibinin with glycyrrhizic acid was 485.45 µg/ml on the HepG2 cell line. CONCLUSION: This in vitro study showed that nano-liposome encapsulation of silibinin with glycyrrhizic acid increased the biological activity of free drugs, increased the stability of silibinin, and synergized the therapeutic effect of silibinin with glycyrrhizic acid. The IC50 of the co-encapsulated nano-liposomes was lower than the combination of free silibinin and glycyrrhizic acid on the HepG2 cell line.

Performance evaluation of fast Fourier-transform continuous cyclic-voltammetry pesticide biosensor.

In this work, a method for the fast monitoring of OPs in flow-injection systems was evaluated. The fast Fourier transform continuous cyclic-voltammetry (FFTCCV) at the carbon-paste electrode in a flowing solution system was used for determination of OPs. In this method the S/N ratio is enhanced by using of fast Fourier transform of the analyte and signal integration. FFTCCV can be considered as a new sensitive, accurate and fast method for determination of drugs and some pesticides. However, in order to obtain better sensitivity for a specific target, experimental parameters should be optimized. Response surface methodology (RSM) was applied to optimize three effective parameters (enzyme activity, multiwall carbon nanotube quantity and acidic sol-gel quantity). The optimum values for the tested parameters were enzyme amount H0.169 U cm⁻², multiwall carbon nanotube (MWCNT) 0.607 mL and acidic sol-gel 1.012 mL. The optimum feed pH, feed flow rate, ATChCl concentration and sweeping-rate were found to be 7.4, 0.34 mL min⁻¹, 0.750 mM and 10Vs⁻¹, respectively. The long-term stability of this flow-through system was 80% of its initial response after 120 days. Based on an incubation time of 12 min, it was found that the detection limit for paraoxon was equal to 1.7×10⁻7 mg L⁻¹ (6.2×10⁻¹³ M). The developed biosensor exhibited good repeatability and reproducibility. This study provides a new, modern, sensitive tool for the analysis of organophosphate pesticides.

Scaling up methadone maintenance treatment for opioid-dependent prisoners in Iran.

BACKGROUND: Research evidence indicates that prisoners in Iran are at risk of drug-related harm, including acquisition of blood-borne infections. In response, several prevention interventions including methadone maintenance treatment (MMT) have been introduced into prisons in Iran. METHODS: This report reviews and presents some important information extracted from published articles, and available documents on HIV sentinel surveillance and provision of MMT inside correctional settings in Iran. RESULTS: Biological surveillance data in 2005 showed that on average about 3% of prisoners in the country tested positive for HIV infection. MTT that constitutes a main component of the Prison Organisation's HIV prevention package is becoming increasingly accessible to opioid-dependent prisoners. Between 2002 and 2008, the number of opioid-dependent prisoners receiving MMT increased steadily from 100 to more than 25000. CONCLUSION: Experiences in Iran suggest that access to MMT would be helpful for reducing illicit drug injection in a prison setting and can be considered as a major intervention for preventing the transmission of blood-borne infections among prisoners.