Suppressive effect of clozapine but not haloperidol on the increases of neuropeptide-degrading enzymes and glial cells in MK-801-treated rat brain regions

MK-801, a noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist, produces neurotoxicity in adult rodent brain, and causes schizophrenia-like psychosis and cognitive dysfunction. Since neuropeptides and neuropeptide-degrading enzymes play important roles in cognitive function, we examined whether or not MK-801-induced schizophrenia-like psychosis is co-related with the changes of these enzymes in rat brain regions. In the present study, we investigated the effect of systemic treatment with MK-801 (0.5mg/kg) on neuropeptide-degrading enzymes, prolyl oligopeptidase (POP) and thimet oligopeptidase (EP 24.15), and glial marker proteins GFAP and CD11b in rat brain regions. The levels of POP and EP 24.15 activities increased significantly three days after treatment with MK-801 in the posterior cingulate/retrosplenial cortices (PC/RSC). Since atypical neuroleptic clozapine but not typical neuroleptic haloperidol prevents the MK-801-induced schizophrenia-like symptoms, we further examined the pretreated effects of the neuroleptics. Clozapine, but not haloperidol, significantly attenuated MK-801-induced changes in the levels of the neuropeptide-degrading enzymes. Immunohistochemical studies on GFAP and CD11b showed the increase in the PC/RSC of MK-801-treated rat brain and the pretreatment with clozapine suppressed these changes. Double immunostain experiments of EP 24.15 and GFAP antibodies demonstrated some co-localization of the neuropeptidase with astrocytes. The present findings suggest that change of neuropeptidases in the brain is in part correlated with changes of glial cells, and may play an important role in the control of schizophrenia-like psychotic disorders.     

Particulate black carbon and gaseous emission from brick kilns in Greater Dhaka region,Bangladesh

Eighteen brick kilns of three brick-making technologies (Fixed Chimney Kiln (FCK), Zigzag, and Hoffmann) were selected to measure the concentrations of particulate matter (PM_2.5) with Aerocet 531S (USA) sampler, black carbon (BC) with Magee Scientific, OT-21 Soot scan Transmissometer (USA), and gaseous pollutants (CO₂, CO, SO₂, NO_x, and volatile organic carbon (VOC)) with Aeroqual 500 gas sampler (New Zealand) to understand the emission scenario from brick sector in Greater Dhaka region, Bangladesh. Emission factor (EF) of each pollutant was computed from their respective concentration for three brick kiln technologies. Ambient PM_2.5 and PM₁₀ were measured in brick kiln premises and 1 km far from the respective kilns to see the effect on the surrounding areas. The PM_2.5 concentration was found on an average of 141?±?86, 128?±?72, and 110?±?53 mg/m³ in FCK, Zigzag, and Hoffmann kilns, respectively. The average BC concentration was found 16.6?±?7.1 (FCK), 11.8?±?4.2 (Zigzag), and 8.9?±?4.4 (Hoffmann) mg/m³. FCK has a greater emission of CO, whereas Zigzag has a higher CO₂ emission. A comparatively higher value of CO₂ and lower value of CO indicates effective combustion of coal, and this is found to be more efficient for Zigzag and Hoffmann compared to traditional FCK. SO₂ and VOC emissions were depending not only on the kiln types but also on the fuel qualities. From EF calculation, approximately 4526 t of PM_2.5, 340 t of BC, 209,776 t of CO₂, 8700 t of CO, 19,441 t of SO₂, and 835,450 t of VOC per year found to emit from 1000 brick kilns. The conversion of traditional FCK to improved one, i.e., Zigzag and/or Hoffman is not a straight forward solution, as CO₂ emission was higher in Zigzag whereas BC and PM_2.5 emissions were higher in FCK. Therefore, considering EF of various pollutants from these three types of kilns, conversion of FCK to Zigzag or Hoffmann could be a better choice.     

Formulation of 3D Printed Tablet for Rapid Drug Release by Fused Deposition Modeling: Screening Polymers for Drug Release,Drug-Polymer Miscibility and Printability

The primary aim of this study was to identify pharmaceutically acceptable amorphous polymers for producing 3D printed tablets of a model drug, haloperidol, for rapid release by fused deposition modeling. Filaments for 3D printing were prepared by hot melt extrusion at 150°C with 10% and 20% w/w of haloperidol using Kollidon^® VA64, Kollicoat^® IR, Affinsiol^?15 cP, and HPMCAS either individually or as binary blends (Kollidon^® VA64 + Affinisol^? 15 cP, 1:1; Kollidon^® VA64 + HPMCAS, 1:1). Dissolution of crushed extrudates was studied at pH 2 and 6.8, and formulations demonstrating rapid dissolution rates were then analyzed for drug-polymer, polymer-polymer and drug-polymer-polymer miscibility by film casting. Polymer-polymer (1:1) and drug-polymer-polymer (1:5:5 and 2:5:5) mixtures were found to be miscible. Tablets with 100% and 60% infill were printed using MakerBot printer at 210°C, and dissolution tests of tablets were conducted at pH 2 and 6.8. Extruded filaments of Kollidon^® VA64-Affinisol^? 15 cP mixtures were flexible and had optimum mechanical strength for 3D printing. Tablets containing 10% drug with 60% and 100% infill showed complete drug release at pH 2 in 45 and 120 min, respectively. Relatively high dissolution rates were also observed at pH 6.8. The 1:1-mixture of Kollidon^® VA64 and Affinisol^?15 cP was thus identified as a suitable polymer system for 3D printing and rapid drug release.     

Physical and Biochemical Characterization of Chemically Treated Pollen Shells for Potential Use in Oral Delivery of Therapeutics

Allergen-free pollen shells obtained from natural pollen grains have recently attracted attention as microcapsules for oral therapeutic delivery. We have recently developed a chemical treatment method that enables successful retrieval of hollow pollen shells from diverse species. A comprehensive characterization is critical to characterize the effects of chemical treatment which will not only benchmark the pollen treatment process but can also lay the foundation of quality control procedures to check allergen-removal efficiency during pollen treatment. Therefore, in this study, we followed the effects of chemical treatment on 4 different pollen species using electron microscopy, elemental analysis, gel electrophoresis, confocal microscopy, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. These analyses revealed that acetone treatment removed lipids from the pollen surface. Phosphoric acid treatment removed proteins and nucleic acids from the pollen core and transformed esters into carboxylic acids. Potassium hydroxide hydrolysis changed carbohydrate composition of the pollen wall. Chemically treated pollen shells exhibited hydroxyl and carboxyl functional groups on their surface. Overall, we propose that confocal microscopy could be used as a rapid scanning technique to visualize the removal of biomolecules, whereas Fourier-transform infrared combined with gel electrophoresis could be used as a more objective approach for analysis and benchmarking.     

Adaptation of Quality by Design-Based Development of Isradipine Nanostructured–Lipid Carrier and Its Evaluation for In Vitro Gut Permeation and In Vivo Solubilization Fate

The present study demonstrated the systematic adaptation of quality by design-integrated approach for the development of novel nanostructured lipid carrier (NLC) of an anti-hypertensive drug isradipine (ISD) to address the inherent challenges such as low solubility and low oral bioavailability. Plackett-Burman design was used for preliminary screening of significant process and formulation variables (p <0.05), which were further processed using Box-Behnken design for the attainment of optimization goal that is, mean particle size (85.7 ± 7.3 nm), drug entrapment efficiency (87.4 ± 3.29%), and in vitro drug release characteristics (92.89 ± 5.47%). The optimized ISD-NLC formulation also demonstrated well-dispersed uniform-shaped particles (polydispersity index 0.207 ± 0.029), high gastrointestinal fluid stability (zeta potential ?10.17 ± 0.59 mV), and higher in vitro gut permeation (21.69 ± 2.38 μg/cm² of ISD-NLC as compared to 11.23 ± 1.74 μg/cm² in ISD suspension). Furthermore, lipolysis studies were performed for the purpose of in vivo fate, and significantly higher drug content of ISD from ISD-NLC in aqueous phase was found (72.34 ± 4.62%) as compared to drug suspension (3.01 ± 0.91%). Relative bioavailability of ISD-NLC and ISD suspension was increased by 4.2-fold and 1.78-fold in the absence and presence of cycloheximide which is a lymphatic uptake inhibitor revealing lymphatic uptake of ISD-NLC in bioavailability improvement. Hence, systematic adaptation of quality by design integrated approach improved gut permeation and potential solubilizaton fate (dynamic lipolysis) of ISD-NLC, which further improved the lymphatic uptake and biodistribution of drug thereby promisingits in vivo prospect and clinical efficacy.     

Design,synthesis and evaluation of alkylphosphocholine-gefitinib conjugates as multitarget anticancer agents

The evolving resistance to the currently used chemotherapeutic agents requires continuous efforts to develop new anticancer agents overcoming resistance and with lower side effects. Polypharmacology via designing a single molecule intercepting multiple signaling pathways is more effective than targeting a single one. Several alkylphosphocholines show anticancer activity via inhibition of Akt phosphorylation. On the other hand, several molecules having quinazoline scaffold elicit anticancer activity through inhibition of epidermal growth factor receptor (EGFR) tyrosine kinases. We report our efforts to develop alkylphosphocholines-gefitinib conjugates as multitarget anticancer agents. The antiproliferative activities of the newly synthesized compounds were evaluated against cell lines representing lung, breast, liver and skin cancers. In addition, the capability of the newly synthesized compounds to inhibit Akt phosphorylation and EGFR tyrosine kinases were determined. The results emphasized the influence of the linkers’ length on the elicited bioactivity. The long chain linkers possessing conjugates were more active regarding both of the elicited antiproliferative effect and inhibition of Akt phosphorylation, while maintained the ability to inhibit EGFR tyrosine kinases. Their cytotoxic activities were superior or comparable to erlotinib and miltefosine.     

Risk modeling of non-communicable diseases using socio-demographic characteristics,lifestyle and family disease history among university students in Bangladesh

Aim

The objective of this study was to determine risk factors for non-communicable diseases (NCDs) on the basis of socio-demographic characteristics, lifestyle-related determinants, environmental and psychological characteristics, and individual and family disease history among university students in Bangladesh.

Study design

Cross-sectional survey.

Methods

Using the WHO STEPwise approach for NCDs, a cross-sectional study was conducted among 1,140 students. The collected data were analyzed using the Statistical Package for Social Sciences (SPSS) software, version 22.

Results

In all, 29.2% of the respondents (BMI?≥?23.00 kg/m²) were overweight and/or obese, and almost two-thirds (65%) of them did not take part in any physical activity (PA). A third (33.3%, p?=?0.002) of male smokers reported health problems and it was found that environmental tobacco smoke (ETS) was significantly responsible for developing asthma (OR?=?0.55; CI?=?0.33–0.93). Individual and family history of NCDs was statistically significant for obesity and asthma and considerably increased the odds ratio for heart disease.

Conclusion

This study shows that the number of students suffering from different types of NCDs is not negligible. Their lifestyle and family history of NCDs are responsible for this to a significant extent. Urgent initiatives should be taken to rein in the spread of NCDs among the youth of Bangladesh.

     

PVA-PEG physically cross-linked hydrogel film as a wound dressing: experimental design and optimization

The development of hydrogel films as wound healing dressings is of a great interest owing to their biological tissue-like nature. Polyvinyl alcohol/polyethylene glycol (PVA/PEG) hydrogels loaded with asiaticoside, a standardized rich fraction of Centella asiatica, were successfully developed using the freeze–thaw method. Response surface methodology with Box–Behnken experimental design was employed to optimize the hydrogels. The hydrogels were characterized and optimized by gel fraction, swelling behavior, water vapor transmission rate and mechanical strength. The formulation with 8% PVA, 5% PEG 400 and five consecutive freeze–thaw cycles was selected as the optimized formulation and was further characterized by its drug release, rheological study, morphology, cytotoxicity and microbial studies. The optimized formulation showed more than 90% drug release at 12?hours. The rheological properties exhibited that the formulation has viscoelastic behavior and remains stable upon storage. Cell culture studies confirmed the biocompatible nature of the optimized hydrogel formulation. In the microbial limit tests, the optimized hydrogel showed no microbial growth. The developed optimized PVA/PEG hydrogel using freeze–thaw method was swellable, elastic, safe, and it can be considered as a promising new wound dressing formulation.     

Resveratrol-loaded PLGA nanoparticles mediated programmed cell death in prostate cancer cells

Resveratrol (RL), a natural polyphenol, is known for its diverse biological effects against various human cancer cell lines. But low aqueous solubility, poor bioavailability, and stability limit its efficacy against prostate cancer. In this study polymeric nanoparticles encapsulating resveratrol (RLPLGA) were designed and their cytotoxic and mode of apoptotic cells death against prostate cancer cell line (LNCaP) was determined. Nanoparticles were prepared by solvent displacement method and characterized for particle size, TEM, entrapment efficiency, DSC and drug release study. RLPLGA exhibited a significant decrease in cell viability with 50% and 90% inhibitory concentration (IC₅₀ and IC₉₀) of 15.6?±?1.49 and 41.1?±?2.19?μM respectively against the LNCaP cells. This effect was mediated by apoptosis as confirmed by cell cycle arrest at G1-S transition phase, externalization of phosphatidylserine, DNA nicking, loss of mitochondrial membrane potential and reactive oxygen species generation in LNCaP cells. Furthermore, significantly greater cytotoxicity to LNCaP cells was observed with nanoparticles as compared to that of free RL at all tested concentrations. RLPLGA nanoparticles presented no adverse cytotoxic effects on murine macrophages even at 200?μM. Our findings support the potential use of developed resveratrol loaded nanoparticle for the prostate cancer chemoprevention/ chemotherapy with no adverse effect on normal cells.     

Development and validation of UPLC-PDA method for concurrent analysis of bergenin and menisdaurin in aerial parts of Flueggea virosa (Roxb. ex Willd.)

Bergenin and menisdaurin are biologically active components which are found in plant Flueggea virosa (Phyllanthaceae). Bergenin has pharmacological actions such as chemopreventive and antihepatotoxic while menisdaurin has an anti-viral activity which needs its evaluation by an analytical method (UPLC-PDA method) that can be applied to the quality control of pharmaceutical preparations. The developed UPLC-PDA method was applied for identification and quantification of standards bergenin and menisdaurin in the methanol extract of F. virosa (FVME). The analysis was carried out using Eclipse C18 (4.6?×?100?mm, 3.5?µm) UPLC column. The optimized chromatographic condition was achieved at 0.16?mL/min flow rate using gradient system with acetonitrile and water as mobile phase. Both biomarkers were measured at λ_max 235?nm in PDA detector at ambient temperature. The developed method furnished sharp and intense peaks of menisdaurin and bergenin at Rt?=?2.723 and 3.068?min, respectively along with r2?>?0.99 for both. The recoveries of bergenin and menisdaurin were found in the range of 99.37–101.49% and 98.20–100.08%, respectively. With other validation data, including precision, specificity, accuracy, and robustness, this method demonstrated excellent reliability and sensitivity. The separation parameters i.e. retention, separation, and resolution factors for resolved standards (bergenin and menisdaurin) were >1, which showed good separation. The quantity of bergenin and menisdaurin in the FVME sample was found as 15.16 and 3.28% w/w, respectively. The developed UPLC-PDA method could be conveniently adopted for the routine quality control analysis.