Nanoliposomes containing limonene and limonene-rich essential oils as novel larvicides against malaria and filariasis mosquito vectors

Background

Mosquito-borne diseases such as malaria and encephalitis are still the cause of several hundred thousand deaths annually. The excessive use of chemical insecticides for transmission control has led to environmental pollution and widespread resistance in mosquitoes. Botanical insecticides' efficacies improvement has thus received considerable attention recently.

Methods

The larvicidal effects of three essential oils from the Citrus family and limonene (their major ingredient) were first investigated against malaria and filariasis mosquito vectors. An attempt was then made to improve their efficacies by preparing nanoliposomes containing each of them.

Results

The larvicidal effect of nanoformulated forms was more effective than non-formulated states. Nanoliposomes containing Citrus aurantium essential oil with a particle size of 52 ± 4 nm showed the best larvicidal activity (LC₅₀ and LC₉₀ values) against Anopheles stephensi (6.63 and 12.29 µg/mL) and Culex quinquefasciatus (4.9 and 16.4 µg/mL).

Conclusion

Due to the green constituents and high efficacy of nanoliposomes containing C. aurantium essential oil, it could be considered for further investigation against other mosquitoes’ populations and field trials.

Loading Pistacia atlantica essential oil in solid lipid nanoparticles and its effect on apoptosis of breast cancer cell line MDA-MB-231

Pistacia atlantica has an anti-cancer effect due to its essential oil which is the major constituent of P. atlantica. Unfortunately, this essential oil evaporates easily and make it less effective. The current research, therefore, aimed to improve the anti-cancer effect of P. atlantica essential oil (PAEO) in solid lipid nanoparticles (SLN). The chemical components of PAEO were assessed by gas chromatography. PAEO-SLNs were prepared by the probe-ultrasonication method, and their particle size, polydispersity index and zeta potential were determined. Encapsulation Efficiency (EE) and Loading Capacity (LC) of formulations was also calculated. Transmission electron microscopy was employed to determine the morphology of optimal formulation (PAEO-SLN4). Furthermore, the anticancer effects of PAEO-SLN4 against MDA-MB-231 cells were evaluated by cellular assays. The results showed that the type of surfactant and loading of the essential oil had a significant effect on size distribution, zeta potential and the polydispersity index. The encapsulation efficiency (EE%) and loading capacity for PAEO-SLN4 were 97.3% and 9.6%, respectively. The cellular assay demonstrates that PAEO-SLN4 could lead MDA-MB-231 cells to apoptosis. The findings also revealed that PAEO-SLN4 can stimulate apoptosis in MDA-MB-231 cells more than the placebo and free PAEO thereby indicating PAEO-SLN4 to be beneficial in breast cancer treatment.

A novel hydrogel scaffold contained bioactive glass nanowhisker (BGnW) for osteogenic differentiation of human mesenchymal stem cells (hMSCs) in vitro

Employing hydrogels as an alternative strategy for repairing bone defects has received great attention in bone tissue engineering. In this study, hydrogel scaffold based on collagen, gelatin, and glutaraldehyde was combined with bioactive glass nanowhiskers (BGnW) to differentiate human mesenchymal stem cells (hMSCs) into the osteogenic lineage and inducing biomineralization. Pure Gel-Glu-Col and bioactive glass nanowhiskers were used as control throughout the paper. Chemical, physical and morphological characteristics of the nanocomposite scaffold were assessed meticulously using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), porosity measurement, water uptake ability, tensile test, and scanning electron microscopy (SEM). To determine the cytotoxicity and cell viability of the hydrogel, MTT assay and Acridine orange (AO) staining were performed. hMSCs seeded on Gel-Glu-Col/BGnW were then incubated with osteogenic differentiation media for 14 days. Biomineralization assays (alkaline phosphatase (ALP) activity, calcium content assay, von Kossa, and Alizarin red staining) were carried out, and osteogenic genes and protein markers were examined using real time-PCR and immunocytochemistry. Results showed that the components of the hydrogel were properly integrated. The mechanical property of hydrogel was enhanced following the addition of BGnW. Cell viability assays confirmed the biocompatibility of the scaffold and increasing the proliferation after incorporating BGnW into pure Ge1-Glu-Col. Our nanocomposite maintained an enhanced ability of biomineralization as compared to its pure counterparts. Molecular investigations revealed an elevated level of osteogenic markers as compared to Ge1-Glu-Col and BGnW. All in all, Gel-Glu-Col/BGnW seems to be a potential candidate for the regeneration of bone tissue.

Voriconazole resistance genes in Aspergillus flavus clinical isolates

OBJECTIVE

The present study was designed to discover novel biomarkers involved in voriconazole resistance in clinical isolates of Aspergillus flavus.

MATERIALS AND METHODS

Two voriconazole non-wild-type and two voriconazole-wild-type A. flavus clinical isolates were selected to evaluate possible molecular mechanism involved in A. flavus resistance to voriconazole using the mutation assessment, Quantitative real- time PCR of cyp51A and cyp51C genes and complementary DNA- amplified fragment length polymorphism technique.

RESULTS

No mutations were seen in the cyp51A and cyp51C genes in voriconazole non-wild-type isolates compared to wild- type and reference strains. Regarding to mRNA expression results, no changes were observed in expression fold of cyp51A and cyp51C mRNA expression level in first non- wild- type isolate compared to wild-type isolate. For second isolate cyp51C mRNA expression level was down regulated (5.6 fold). The set of genes including ABC fatty acid transporter XM- 002375835 and aldehydereductase XM- 002376518 and three unknown functional genes were identified. Based on results, the over-expression of AKR1 and ABC fatty acid transporter in the voriconazole non- wild- type isolates suggests these genes could represent a novel molecular marker linked to the voriconazole resistance in A. flavus.

CONCLUSION

The results obtained in this study showed a novel finding as the authors identified AKR1 and ABC fatty acid transporter genes as possible voriconazole target genes in Iranian clinical isolates of A. flavus.

Assessment of microRNA-146a in generalized aggressive periodontitis and its association with disease severity

BACKGROUND AND OBJECTIVE

MicroRNA-146a (miR-146a) is a small noncoding RNA that plays a critical role in the negative regulation of the innate immune response, and the dysregulation of miR-146a has been associated with several inflammatory disorders. In generalized aggressive periodontitis (GAgP) the degree of clinical inflammation appears to be similar to that of chronic periodontitis, and, in this situation, age of onset and family history are important additional criteria for diagnosis. This study was performed to evaluate the level of miR-146a expressed in gingival tissues of patients with GAgP and its association with disease severity.

MATERIAL AND METHODS

Gingival samples from 18 patients with GAgP and 10 healthy subjects were collected and the level of miR-146a and its targets, including necrosis factor-alpha, interleukin-1beta, and interleukin-6, were assessed using real-time PCR. Clinical parameters, including probing depth and clinical attachment loss, were measured and their correlations with the level of miR-146a were determined.

RESULTS

Our results demonstrated an elevation in the level of miR-146a expressed in patients with GAgP compared with healthy controls (P < .001), which was directly associated with disease severity (P < .05). Overexpression of miR-146a was accompanied by a reduction in the levels of pro-inflammatory cytokines.

CONCLUSIONS

Our findings suggest that there is an association between miR-146a and GAgP and imply that miR-146a may serve as an indicator of periodontal disease severity. However, further studies and additional information are required to confirm this relationship and the precise role of miR-146a in the development and/or progression of periodontitis.

Design of a dual-promoter expression vector harboring Sag1 and Gra7 genes from Toxoplasma gondii (RH strain)

Toxoplasmosis, a parasitic disease caused by Toxoplasma gondii, has possible irreparable consequences in immunocompromised patients and fetuses. Finding an effective method of prevention, such as vaccination, is crucial because of the global distribution of the parasite and the lack of effective anti-toxoplasmosis drugs. The Sag1 and Gra7 antigens of T. gondii can induce strong humoral and cell-mediated immune responses. Therefore, to develop a novel DNA vaccine against toxoplasmosis, we prepared a eukaryotic construct expressing the Sag1 and Gra7 genes of T. gondii (RH strain). We then verified the ability of this construct to produce the corresponding Sag1 and Gra7 antigens in mammalian cells. Using specific primers, the complete coding sequences of Sag1 and Gra7 genes were amplified by polymerase chain reaction (PCR) from the genomic DNA of T. gondii. Then, both genes were subcloned into pVitro2-neo-mcs plasmid. The pVitro-Sag1-Gra7 construct was subjected to colony PCR, enzymatic digestion, and sequencing to confirm successful subcloning. Sag1 and Gra7 expression in HeLa cells was investigated. Sag1 and Gra7 were successfully subcloned in pVitro2-neo-mcs plasmid. The expression of Sag1 and Gra7 in HeLa cells was confirmed through Western blot analysis. The recombinant pVitro-Sag1-Gra7 construct that simultaneously produces Sag1 and Gra7 antigens in one mammalian cell may be used to develop a novel protective vaccine against toxoplasmosis.

Optimized Transferosomal Bovine Lactoferrin (BLF) as a Promising Novel Non-Invasive Topical Treatment for Genital Warts Caused by Human Papiluma Virus (HPV)

Human papillomavirus (HPV) cause common warts, laryngeal papilloma, and genital condylomata and might lead to development of cervical cancer. Lactoferrin (LF) is a member of the transferrin family, which has antiviral activity against HPV-16.  LF is an important player in the defense against pathogenic microorganisms and has also been shown to have activity against several viruses including herpesvirus, adenovirus, rotavirus, and poliovirus. Bovine LF (BLF) has been reported to be a more potent inhibitor of HPV entry in comparison to human LF. The goal of the present study is to formulate, evaluate and optimize transfersomal vesicles as a non-invasive transdermal delivery system which assumed to be a suitable for treatment of genital warts. Transfersomes have been prepared by two methods including reverse phase evaporation and thin film hydration with different ratios of cholesterol: lecithin: DOTAP in the presence of SDS or Tween 80. The transferosomes were then evaluated regarding size, polydispersity, and LF loading. In-vitro release studies in pH 5.3 and 7.4, stability evaluation in 4 °C and 25 °C, and TEM imaging hve been performed on optimized transferosomal lactoferrin. The optimized transferosomes were found to have 100 nm sizes with good polydispersity index and encapsulation efficiency of 91% for lactoferrin as well as sustained release of lactoferrin during 24 h. Transferosomal lactoferrin efficacy was evaluated by MTT assay. It was seen that the viral inhibitory concentration (IC50) of transfersomal lactoferrin has been significantly improved to nearly one tenth in comparison to free lactoferrin.

Promoting medication adherence among patients with bipolar disorder: a multicenter randomized controlled trial of a multifaceted intervention

BACKGROUND

The present research aimed to investigate the efficacy of a multifaceted intervention that included motivational interviewing (MI) and psychoeducation in improving medication adherence (MA) among patients with bipolar disorder (BD).

METHOD

A multicenter, cluster randomized, observer-blind, controlled, parallel-group trial was conducted in ten academic centers in Iran. Patients with BD were randomly assigned to the experimental group (EXP; n = 136) or the usual care group (UC; n = 134). The EXP group received five sessions of MI and psychoeducation together with their family members. The primary outcome measure was changes in scores on the Medication Adherence Rating Scale from baseline to 6 months post-intervention. Other outcome measures included serum levels of mood stabilizers, clinical symptoms, quality of life, as well as measures of intention, beliefs about medicine, perceived behavioral control, automaticity, action and coping planning, and adverse reactions.

RESULTS

Medication adherence improved over time in both groups, but patients in the EXP group improved more (baseline score: 6.03; score at the sixth month: 9.55) than patients in the UC group (baseline score: 6.17; score at the sixth month: 6.67). In addition, patients in the EXP group showed greater improvement than patients in the UC group in almost all secondary outcomes 6 months following the intervention.

CONCLUSIONS

Multifaceted interventions that include motivational-interviewing and psychoeducation can significantly improve MA and clinical and functional outcomes in patients with BD.

TRIAL REGISTRATION NUMBER

The trial was registered with theClinicalTrials.gov database (NCT02241863) https://clinicaltrials.gov/ct2/show/NCT02241863.

Is there an association between Health Related Quality of Life, socio-demographic status and Fatigue in Patients with Chronic Hepatitis B?

BACKGROUND

Chronic hepatitis B (CHB) is a serious and prevalent disease which may negatively influence health related quality of life (HRQOL) and fatigue. The aim of the present study was to examine the relationship between demographic variables, HRQOL, and fatigue.

METHODS

A cross-sectional study was conducted involving 418 Iranian patients with CHB (average age 44.1 years, majority males). Participants completed a multidimensional fatigue inventory, chronic liver disease questionnaire, Euro quality of life-five dimensions questionnaire, and demographic information. Bivariate analyses were conducted using the Spearman correlation and Mann-Whitney U test. Hierarchical logistic regression modeling identified independent predictors of fatigue.

RESULTS

The most prevalent problems related to HRQOL were anxiety/depression and pain/discomfort. Except for reduced motivation other dimensions of fatigue were significantly higher among those with CHB compared to healthy controls (p<0.05). Age, sex, education, employment, disease stage and all HRQOL subscales were significantly related to fatigue level. The Nagelkerke R Square for the logistic regression model was 0.542.

CONCLUSIONS

Poor HRQOL and fatigue are widespread among patients with CHB. Given these associations between demographic, psychological, and other HRQOL dimensions and fatigue, interventions that address these factors may help to reduce fatigue in patients with CHB.

Barriers to Liposomal Gene Delivery: from Application Site to the Target

Gene therapy is a therapeutic approach to deliver genetic material into cells to alter their function in entire organism. One promising form of gene delivery system (DDS) is liposomes. The success of liposome-mediated gene delivery is a multifactorial issue and well-designed liposomal systems might lead to optimized gene transfection particularly in vivo. Liposomal gene delivery systems face different barriers from their site of application to their target, which is inside the cells. These barriers include presystemic obstacles (epithelial barriers), systemic barriers in blood circulation and cellular barriers. Epithelial barriers differ depending on the route of administration. Systemic barriers include enzymatic degradation, binding and opsonisation. Both of these barriers can act as limiting hurdles that genetic material and their vector should overcome before reaching the cells. Finally liposomes should overcome cellular barriers that include cell entrance, endosomal escape and nuclear uptake. These barriers and their impact on liposomal gene delivery will be discussed in this review.

Terpene-loaded Liposomes and Isopropyl Myristate as Chemical Permeation Enhancers Toward Liposomal Gene Delivery in Lung Cancer cells; A Comparative Study

Gene therapy is in its development stage as a novel method for cancer treatment. Liposomes look promising as gene delivery vectors; however, investigations have shown that these vesicles are not doing well in some cases. It was decided here to investigate the possibility of augmentation of liposomal gene delivery by chemical penetration enhancers. Cationic liposome containing antisense oligonucleotide (AsODN) against lung cancer was prepared by ethanol injection method. Liposomal cineole and limonene (as enhancers) were prepared by film hydration method. Isopropyl myristate (IPM) was also investigated as penetration enhancer. Liposomes were evaluated for their size, zeta potential and encapsulation efficiency. Cancer cells (A549) were pretreated with liposomal terpenes prior to treatment with liposomal antisense or scrambled oligonucleotide. Cell viability was evaluated by MTT assay. Oligonucleotide -containing liposome showed particle size of about115 nm and zeta potential of 0.6 mV. Liposomal cineole significantly (P<0.05) increased specific activity of liposomal antisense but limonene didn't show such an effect. IPM increased both specific and non-specific cytotoxicity of Oligonucleotide. These results show that penetration enhancers (such as cineole) may be used for improving liposomal gene delivery and to reduce non-specific toxicity. Concentration and chemical nature of enhancer has prominent effect in their efficacy.

Improving cellular uptake and in vivo tumor suppression efficacy of liposomal oligonucleotides by urea as a chemical penetration enhancer

BACKGROUND

Liposomes are among the most widely used carriers for the delivery of antisense oligonucleotides (AsODNs) to intracellular targets. Although different strategies have been employed, the question of how to improve liposomal uptake and enhance the release of AsODN into cytoplasm still remains to be answered with respect to the use of a safe, easy and economic method. In the present study, the possibility of enhancing such processes at cellular and animal levels using urea as a penetration enhancer was investigated.

METHODS

To perform this investigation, a cationic liposome containing an AsODN against protein kinase (PKC)-α was prepared, and the effect of urea on its cellular internalization and the related sequence-specific inhibition of gene expression in human lung adenocarcinoma A549 cells were investigated by flow cytometry and the reverse transcriptase-polymerase chain reaction, respectively. In in vivo studies, a xenograft lung tumor was established in nude mice by A549 cells and the enhancement effect of urea toward the effects of liposomal AsODN on tumor growth was investigated.

RESULTS

Cellular studies revealed that urea treatment increases liposomal uptake and the release of AsODN into the cytoplasm by approximately 40%. Sequence-specific inhibition of target gene PKC-α expression was also increased by approximately two-fold by urea at 200-300 nM AsODN. In animal studies, urea significantly decreased the tumor volume (approximately 40%) and increased its doubling time from approximately 13 days to 17 days.

CONCLUSIONS

Urea, and possibly other membrane fluidizers, could be regarded as penetration enhancers for liposomal AsODN delivery and may improve the therapeutic effect of these gene-therapy vectors at both cellular and animal levels.

Preparation and in-vitro Evaluation of an Antisense-containing Cationic Liposome against Non-small Cell Lung Cancer: a Comparative Preparation Study

The current methods for treatment of cancers are inadequate and more specific methods such as gene therapy are in progress. Among different vehicles, cationic liposomes are frequently used for delivery of genetic material. This investigation aims to prepare and optimize DOTAP cationic liposomes containing an antisense oligonuclotide (AsODN) against protein kinase C alpha in non-small cells lung cancer (NSCLC). To perform this investigation, two different methods of ethanol injection and thin film hydration were used to prepare AsODN-loaded DOTAP liposomes. The formulated liposomes were then evaluated for their morphology, particle size, zeta potential and encapsulation efficiency, and the best formulation was chosen. In-vitro growth inhibitory effect of encapsulated ODN on A549 cells were evaluated by MTT and colonogenic assay. The physical and serum stability of liposomal ODN were also evaluated. Thin film hydration method resulted in large liposomes that required downsizing by extrusion with an encapsulation efficiency of 13%. Ethanol injection, in a single step gave liposomes with a small size of 115 nm and an encapsulation efficiency of around 90% which were physically stable for 6 months. The optimized liposome could protect oligonucleotides from degradation by nuclease. Cell studies showed a 20% sequence-specific inhibition of cell growth in MTT assay and revealed an LC50 of 103 nM in colonogenic studies. In conclusion, ethanol injection was able to provide suitable liposomes from the permanently charged DOTAP. Also the resulted liposomes were able to inhibit the growth of lung cancer cells.

Differential expression analysis of balding and nonbalding dermal papilla microRNAs in male pattern baldness with a microRNA amplification profiling method

BACKGROUND

  Male pattern baldness or androgenetic alopecia is a common disorder affecting almost 50% of men throughout their lifetime, with androgens and genetics having significant contributing aetiologies. In contrast to the positive regulatory effect of androgens on body hair growth, they are thought to alter scalp hair follicle behaviour pathophysiologically, leading to male pattern baldness. However, the exact mechanisms of this paradoxical action have not yet been elucidated. The role of microRNAs, a novel group of noncoding RNAs impacting almost every aspect of biology, health and human diseases, has been documented in hair follicle formation. In addition, their deregulation in cancer of the prostate, a target organ of androgens, has also been well established.

OBJECTIVES

To investigate the possible contribution of microRNAs in the pathophysiology of male pattern baldness.

METHODS

We initially screened microRNA expression profiles of balding and nonbalding hair follicle papillae with a sensitive microRNA cloning method, microRNA amplification profiling, and statistically analysed significant differentially expressed microRNAs in balding relative to nonbalding dermal papillae, with real-time polymerase chain reaction as a confirmatory method to quantify expression in eight individuals affected with the disorder.

RESULTS

  We detected the significant upregulation of miR-221, miR-125b, miR-106a and miR-410 in balding papilla cells.

CONCLUSIONS

  We found four microRNAs that could participate in the pathogenesis of male pattern baldness. Regarding the strong therapeutic potential of microRNAs and the easy accessibility of hair follicles for gene therapy, microRNAs are possible candidates for a new generation of revolutionary treatments.

Stress, coping strategies and related factors in a sample of Iranian adolescents

BACKGROUND

Since the stress and coping are the most reported problems by adolescents, this study aims to apprise the stressors, coping strategies and influential factors among male adolescents.

METHODS

The effect of stressors, coping strategies and some demographics variables were studied in 402 male adolescents in Tehran, Iran. A self-administered questionnaire was used to collect the data. A multiple regression was performed to assess factors related to perceived stress.

RESULTS

The mean age of adolescents was 15.44 (SD=0.68) years. The mean value of perceived stress for the whole sample was 17.99 (SD=6.02). Cognitive/emotional coping was the most frequent coping style. The findings revealed that there was a significant correlation between perceived and accumulative stress. In multiple regression analysis, the accumulative stress, social resources, parent`s education and grade point average were found to be significant predictors of perceived stress.

CONCLUSION

The findings suggest that increased level of perceived stress is associated with accumulative stress, social resources and parent`s education that are modifiable factors. Stress management education might be a solution to overcome increased perceived stress.

The selective cyclooxygenase-2 inhibitor, the compound 11b improves haloperidol induced catatonia by enhancing the striatum dopaminergic neurotransmission

A substantial amount of evidence has proposed an important role for Cyclooxygenase-2 (COX-2) enzyme in brain diseases and affiliate disorders. The purpose of this research was studying the effects of COX-2 selective inhibition on haloperidol-induced catatonia in an animal model of drug overdose and Parkinson's disease (PD). In this study, the effect of acute and Sub-chronic oral administration of a new selective COX-2 inhibitor, i.e. the compound 11b or 1-(Phenyl)-5-(4-methylsulfonylphenyl)-2-ethylthioimidazole, in a dosage of 2, 4 and 8 mg/kg on haloperidol-induced catatonia was evaluated and compared to the standard drug scopolamine (1 mg/kg) by microanalysis of Striatum dopaminergic neurotransmission. The results showed a very high potency for 11b in improving the catalepsy by enhancing the dopaminergic neurotranmission (p < 0.05). In addition, statistical analysis showed the dose- and time-dependent behavior of the observed protective effect of 11b against the haloperidol-induced catatonia and enhancement of the dopaminergic neurotransmission. These findings are additional pharmacological data that suggest the effectiveness of COX-2 inhibition in treatment of schizophreny-associated rigidity.

The profile of cytokines and IgG subclasses in BALB/c mice after immunization with Brucella ribosomal gene

This study was evaluated the ability of DNA vaccine encoding L7/L12 protein of Brucella sp. to induce cellular and humoral immune responses in BALB/c mice and the profile of cytokines and IgG sub classes were determined. Intra muscular vaccination of mice using L7/L12 gene. Three vaccinations at 3 week intervals were performed. Cytokines and IgG subclasses were analyzed 3 week after the last DNA vaccination. Splenic lymphocytes from L7/L12pCDNA3-vaccinated mice produced high levels of IFNy (3100 pg mL(-1)) and low levels of IL-5 (300 pg mL(-1)), 3 weeks post-vaccination. The L7/L12pCDNA3 immunizations elicited high IgG2a isotype response in mice immunized. This antigen also induced IgG1 titers which were slightly lower than the IgG2a titers. Immunological analysis shows the appropriate immune response in BALB/c mice model after vaccination with L7/L12 gene. The high level of IFNgamma and low level of IL-5 in combination with high IgG2a/IgG1 ratio show the activation of Th1 cell response. The lower bacterial cfu from vaccinated mice in comparison with control groups show the efficiency of L7/L12 DNA vaccination in mice model.

Dopaminergic but not glutamatergic neurotransmission is increased in the striatum after selective cyclooxygenase-2 inhibition in normal and hemiparkinsonian rats

In the present work, we studied the effect of the selective cyclooxygenase-2 (COX-2) inhibitors, compound 11 g, celecoxib and selective COX-1 inhibitor SC-560 (intraperitoneally and acutely) on striatal glutamatergic and dopaminergic neurotransmission in normal and substantia nigra pars compacta (SNc)-lesioned rats using the microdialysis technique. We also investigated the effect of acute COX inhibition on the damaged SNc neurons. Our results indicate a significant increase in dopaminergic neurotransmission and a decrease in glutamatergic neurotransmission (P<0.05) only after selective COX-2 inhibition in the striatum of normal and hemiparkinsonian rats. Nonetheless, neither COX-1 nor COX-2 inhibitors showed any improvement in the damaged SNc neurons.

Formulation and in vitro Evaluation of Eudragit L100 piroxicam

The aim of this study was to formulate and evaluate controlled release preparations of a water-insoluble drug using Copolymers synthesized from acrylic and methacrylic acidesters (Eudragit L 100) as the retardant material. Microspheres were prepared by solvent evaporation method using an alcohol / liquid paraffin system. Span60 was used as the droplet stabilizer. The prepared microspheres were characterized for their micromeritic properties and drug loading, as well as by differential scanning calorimetry. The in vitro release studies were performed first in pH1.2 and then pH 6.8, phosphate buffer. The prepared microspheres were yellow, and spherical in shape. The drugloaded microspheres showed 71-85% of entrapment and release was extended up to 7 h. The differential scanning calorimetry thermographs showed stable character of drug in the drug-loaded microspheres and revealed the absence of drug-polymer interactions. The best-fit release kinetics was achieved with Higuchi plot. The release of drug was influenced by the drug to polymer ratio and particle size that was found to be diffusion controlled.

Cerebellopontine angle medulloblastoma

An extremely rare case of a right cerebellopontine angle medulloblastoma in a five year old Malay girl which had eroded into the petrous bone and extended into the temporal fossa is reported. Combined subtemporal and retromastoid approach to achieve gross total surgical resection was achieved followed by radiotherapy and chemotherapy.