Enhancement in brain uptake of vitamin D3 nanoemulsion for treatment of cerebral ischemia: formulation, gamma scintigraphy and efficacy study in transient middle cerebral artery occlusion rat models.

AIM: For the treatment of cerebral ischaemia, vitamin-D3 loaded nanoemulsions were developed. METHOD: Tween 20 and polyethylene glycol were chosen as surfactant/co-surfactant, while oleic acid as the oil phase. The formulation was characterised for various in-vitro parameters. Targeting efficiency was investigated through radiometry, gamma scintigraphy and efficacy was studied in transient middle cerebral artery occlusion (MCAo) rat model. RESULT: Vitamin D3-nanoemulsion showed a mean size range of 49.29 ± 10.28 nm with polydispersity index 0.17 ± 0.04 and zeta potential 13.77 mV. The formulation was found stable during thermodynamic stability study and permeated within 180 min through sheep nasal mucosa (permeation coefficient 7.873 ± 0.884 cm/h). Gamma scintigraphy and radiometry assay confirmed better percentage deposition (2.53 ± 0.17%) of 99mTc-vitamin D3-nanoemulsion through nasal route compared to IV administered 99mTc-vitamin D3 solution (0.79 ± 0.03%). Magnetic Resonance Imaging (MRI) of the ischaemic model confirmed better efficacy of vitamin D3-nanoemulsion. CONCLUSION: This work demonstrated better permeation, deposition, and efficacy of vitaminD3-nanoemulsion through the intranasal route.

Decontamination of rat and human skin experimentally contaminated with 99mTc, 201Tl and 131I radionuclides using "Dermadecon" - a skin decontamination kit: an efficacy study.

Radioactive skin contamination is one of the most likely risks which occurs after accidental or occupational radiological accidents apart from internal contamination. In such cases where the radioactive contamination has occurred, the person who is contaminated should be decontaminated as early as possible to reduce the damaging health effects of radiation. In the present study, the decontamination efficiency of a developed skin decontamination kit "dermadecon" has been evaluated in animal models and human subjects using gamma scintigraphy. Decontamination efficiency (percentage of the radioactive contaminant removed) was calculated for each radioactive isotope of the study and compared with control where general washing procedure was followed using liquid and soap. The effectiveness of the kit was calculated in animal model with respect to 99mTc-sodium-pertechnetate (99mTcO4-), 201TlCl and 131I and was found 92.84 ± 4.9%, 91.18 ± 3.23% and 94.67 ± 2.92%, respectively. Whereas, in case of human skin, the decontamination efficiency for 99mTcO4- was observed to be 95.00 ± 3.21%. On the basis of findings from the study, it can be concluded that the decontamination agents of the used skin decontamination kit are effective for removal of localized radioactive contaminants from skin, as compared with normal decontamination using soap and water.

Pulmonary delivery of nanosized alendronate for decorporation of inhaled heavy metals: formulation development, characterization and gamma scintigraphic evaluation.

CONTEXT: Medical management of heavy metal toxicity including radioactive ones is the cause of concern because of their increased use in energy production, healthcare and mining. As inhalation is one of the primary routes for internalization, a formulation is needed to trap metal(s) at the portal of entry itself. OBJECTIVE: Objective was to formulate and characterize a nanonized dry powder inhaler (DPI) formulation of alendronate sodium as potential inhalable antidote for chelating metal toxicants. METHODS: In vitro binding studies of alendronate with respect to seven non-radioactive heavy metals were carried out using UV-spectroscopy and HPLC. Nanonizing of alendronate particles was achieved by antisolvent precipitation using Pluronic-F68 as stabilizer. Characterization was done with the help of SEM, TEM FT-IR, XRD, DSC, NMR spectroscopy and PSD studies. In vitro and in vivo pulmonary deposition studies were carried out using gamma scintigraphy, followed by a limited pharmacokinetic study in humans. RESULTS: In vitro binding studies confirmed the chelating action of alendronate. Anderson cascade impaction showed that nano-alendronate exhibited significantly higher respirable fraction (58.25 ± 1.32%) compared to the micronized form (28.7 ± 0.59%). Scintigraphy results showed significant increase in the alveolar deposition of drug post-nanonizing. CONCLUSION: Results strongly indicate the role of nano-alendronate DPI as potential inhalable antidote for neutralizing heavy metal toxicity, including radio-metal contamination.

Protective Effect of Organ Preservation Fluid Supplemented With Nicorandil and Rutin Trihydrate: A Comparative Study in a Rat Model of Renal Ischemia.

OBJECTIVES: The objective of organ preservation is sustained viability of detached/removed/isolated organs and subsequent successful posttransplant outcomes. Nicorandil (an ATP-sensitive potassium channel opener) is an efficacious agent to preserve lungs and heart. Rutin trihydrate (an antioxidant) inhibits free radical-mediated cytotoxicity and lipid peroxidation. We aimed to evaluate the efficacy of nicorandil and rutin trihydrate to enhance kidney preservation. MATERIALS AND METHODS: We prepared 2 versions of organ preservation fluid, supplemented with either nicorandil or rutin trihydrate, and used 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium assays to evaluate the efficacy of these solutions in vitro (HEK293 human embryonic kidney cells), according to various cellular parameters such as ATP levels, reactive oxygen species, and cell viability. We also investigated the in vivo preservation efficacy in a rat model of renal ischemia and evaluated the immunohistological expression of apoptotic markers (caspase 3) in preserved rat kidney. RESULTS: We observed significant improvement of intracellular ATP levels (32 999 ± 1454 pmol/cell, n = 3; P < .05) in cells preserved in the nicorandil- supplemented solution compared with Custodiol solution (23 216 ± 1315 pmol/cell). Reactive oxygen species declined 1.25-fold (P < .05) in the presence of rutin trihydrate. Cell viability assays revealed a 4.8-fold increase in viability of renal cells preserved in the solutions supplemented with nicorandil or rutin trihydrate after 24-hour incubation compared with controls. In vivo, there were significant effects on serum creatinine (0.5480 ± 0.052, 0.956 ± 0.043 mg/dL) and blood urea nitrogen (85.36 ± 4.64, 92.85 ± 3.15 mg/dL) with the nicorandil and rutin trihydrate solutions, respectively. We observed suppressed expression of the apoptotic marker caspase 3 in groups treated with the 2 supplemented preservation fluids. CONCLUSIONS: Our results showed that solutions of organ preservation fluid supplemented with either nicorandil or rutin trihydrate can ameliorate cellular problems/dysfunction and facilitate sustained impro - vement of tissue survival and subsequent organ viability.

Transient cell function disruption by low dose acute exposure of ionizing radiation.

Incubation of BMG-1 cells with thallium chloride (201Tl) in the range of diagnostic dose did not show a smooth uptake curve and appeared to have an unsuspected deviation in initial phase. In the present study this unexpected phenomenon was explored, using commonly used radionuclides (viz., 201Tl and 131I). Comparison was made with technetium-99m pertechnetate (99mTcO4(-)) and technetium-99m labeled methoxyisobutylisonitrile (99mTc-MIBI) that are known to show conventional 2 phase graph representing inflow and outflow segments. Serial in vitro, ex-vivo and in vivo gamma scintigraphy as well as NMR spectroscopy experiments were conducted to corroborate the results. BMG-1 cells demonstrated a four-phase uptake pattern with 201Tl as compared to a conventional biphasic pattern with 99mTc-MIBI. Flow cytometry data however did not reveal any 201Tl induced cell injury. Further, mice tissue extracts injected with 201Tl also showed a transient depression in its uptake. Scintigraphy experiments in rabbits administered with diagnostic dose of 201Tl and 131I confirmed the in vitro and ex vivo findings. Further, proton NMR spectroscopy showed decrease in the level of choline at 3 h and 24 h in 201Tl treated animals as compared to control. Phosphoethanolamine peak firstly decreased at 3 h but reached normal level at 24 h time point. No significant change was observed in the level of betaine. This transient reduction in internalization of 201Tl and 131I may represent a hitherto unknown acute effect of low dose radiation, i.e., transient depression in Na+-K+ ATPase pump activity without any apparent evidence of cell damage, representing a transient cell membrane dysfunction. The phenomenon may present a mechanistical explanation of 'thyroid stunning' at cellular level and suggest that it may be more universal in nature than suspected till now.

Intranasal solid lipid nanoparticles for management of pain: A full factorial design approach, characterization & Gamma Scintigraphy.

Pain is a noxious stimulus caused due to tissue damage and varies from mild to severe. Nalbuphine (NLB) is an approved, inexpensive, non-controlled, opioid agonist/antagonist analgesic used worldwide in various clinical settings for pain management. The current study aims to formulate NLB loaded solid lipid nanoparticles (SLNs) using solvent injection technology. The morphological and chemical structure of the developed SLNs were characterized using Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM) and Fourier Transformation Infrared Spectroscopy (FTIR). The results revealed from the point prediction confirmation in design expert software was the formulation of NLB-SLNs with an average particle size of (170.07 ± 25.1 nm), encapsulation efficiency (93.6 ± 1.5%) & loading capacity of 26.67%. The in-vitro permeation of developed NLB-SLNs was observed to be 94.18% at 8 h when compared with NLB solution whose maximum permeation was seen within 3 h of application. Efficacy of the formulation was also evaluated using eddy's hot plate method, where the onset of action started within 10 min of administration, and the maximum effect was observed at 1 h. The NLB-SLNs was screened for cytotoxicity in human embryonic kidney cells (HEK-293), and the dosage was considered safe when administered intranasally in animal since no detectable effect to the brain was observed. Biodistribution and gamma scintigraphy study of NLB-SLNs showed the prepared formulation reaching the target site, i.e. brain and was retained. Conclusively, the prepared NLB-SLNs formulation was safe and effective in producing an analgesic effect in vivo.

A Comparative Study of Chitosan Gel and Soframycin in the Management of Wounds.

Wounds and related injuries remain a major cause of death and disability. Healing of wound is a complex, highly regulated process that includes cellular, molecular, biochemical, and physiological events that permit living organisms to repair accidental lesions. Therefore, dealing with wounds has always been a subject of concern to the world, and demand for products in wound management had increased to $9.3 trillion worldwide in the health care industry, affecting economic growth. The present work aimed to assess the wound healing effect of chitosan, and a comparative profile with soframycin is established in experimental animals. Enormous research reports, the wound healing properties of chitosan, but the protective mechanism implicated in wound healing activity of chitosan is unknown. In addition to this, we evaluated the anatomical, macroscopical, and histopathological alterations in wounds of experimental rats. Collagenase activity was performed to determine the granulation tissue formation and epithelialization of wounds treated with untainted chitosan. Wounds treated with glycerated chitosan gel, that is, GCG-3 (high degree of deacetylation), showed faster healing with highest percentage of contraction as compared with the soframycin-treated group. The healing of wounds was found to be 85% in GCG-3 on the sixth day of treatment, showing significant (P < .001) improvement in epithelial tissue. The collagenase activity in GCG-3 was 192 unit/mg of protein. Wound reepithelialization was found to be to 94 ± 4% in case of the GCG-3-treated group and 87 ± 5% in the soframycin-treated group. Higher degree of deacetylation in the chitosan, GCG-3, warrants its use in the treatment and management of dermal wounds.

Submental nalbuphine exhibits improved efficacy in ameliorating acute pain in prehospital emergent conditions; a comparative study with conventional intramuscular using gamma scintigraphy.

BACKGROUND: Nalbuphine (NLB) is a kappa-agonist and mu-partial antagonist, widely used for opioid withdrawal de-addiction, opioid-induced pruritis and as emergent analgesia. OBJECTIVE: The present study aimed to assess the safety and efficacy of NLB in pain sensitization, through a submental route so as to provide faster management in emergent situations. MATERIALS & METHODS: In-vivo efficacy and safety studies of NLB-submental injection were assessed in Sprague-Dawley(SD) rats. For eddy's hot plate study, animals were allocated into three groups, the first group served as normal control; group II received NLB (through submental route at 1.2 mg/kg); group III received NLB (through intramuscular route at 1.2 mg/kg). Response latency (in terms of response latency) was measured at 10, 30 & 60 min in all the experimental groups. Safety studies were carried out according to OECD 423. In-vitro release study was conducted using a cellulose dialysis membrane (12,000 KDa). The biodistribution and release kinetics studies were carried out using gamma scintigraphy studies in New Zealand rabbits and humans respectively. RESULTS: The response latency of NLB from the submental route was found to be 7.17 (SD 1.47) seconds and in the case of the intramuscular route it was calculated as 4.00 (SD 1.26) seconds at 10 min. The data depicts the better efficacy of submental injection in ameliorating pain than the intramuscular injection. Toxicity studies predict the safe profile through a submental route. The release kinetics in humans of submental NLB was 46% faster as compared to the intramuscular site of injection. The NLB injection through both routes was compared by non-invasive gamma scintigraphy technique and we found that submental injection has faster (within 10 min) onset of action & distributes rapidly. CONCLUSION: The submental route of NLB is faster, more efficacious than the intramuscular route. Thus, we conclude that in the case of emergent scenarios (i.v or i.m. route is compromised), where immediate relief is necessary, the submental route is a preferred choice.

Alpha ketoglutarate nanoparticles: A potentially effective treatment for cyanide poisoning.

The purpose of this research work was to prepare nanosized formulation of alpha ketoglutarate as dry powder inhaler for cyanide poisoning. Nanosizing can be approached by solid phase and liquid phase method. The different conditions encountered in both these approaches can greatly affect the particle characteristics. In this study milling and precipitation technique were compared to study their effect on α-KG particles characteristics. Differences in choice of stabilizers were observed between the two processing techniques. Sonication processes followed by HPH produced small sized particles in which Pluronic F68 was employed as stabilizing agent. Precipitation approach produced ultrafine drug particles by utilizing combination of stabilizers (PVA+PEG 400). Amongst the two sonication processes, probe sonication process produced well stabilized small sized particles. The designed particles showed 43.13±2.36% lung deposition when compared with ultrasonication and precipitation technique that showed 31.69% and 21.67% respirable fraction. The MMAD of the designed particles was found suitable for deep alveolar deposition. Clinical studies (Phase-I trial) showed whole lung deposition of 52.51% for DPI. The P/C ratio was found to be 1.02 suggesting uniform distribution of particles in different lung compartments.

Development of microbial trigger based oral formulation of Tinidazole and its Gamma Scintigraphy Evaluation: A promising tool against anaerobic microbes associated GI problems.

Tinidazole is a versatile anti-amoebic and anti-anaerobic drug used in treatment of intestinal infection. The aim of present study was to develop and evaluate a guar gum based novel target release Tinidazole matrix tablet in animal models and healthy human volunteer using Gamma Scintigraphy technique. Anti-anaerobic and anti-protozoal activity of the developed formulation was studied in vitro against Bacteroides fragilis and Dentamoeba fragilis. Tinidazole was successful radiolabelled with (99m)Tc-pertechnetate using stannous chloride as a reducing agent and stable up to 24h in normal saline and serum. Radiolabeled formulation was evaluated in 6 Newzealand white rabbits by gamma Scintigraphy in static manner up to 24h for its retention in gastrointestinal tract (GIT). Similar set of study was conducted in 12 healthy human volunteers for similar objective Scintigraphy images of healthy human volunteer showed retention of optimized formulations in stomach up to 60min, from where it moved to duodenum further and reached ileum in around 5h. However, initiation of drug release was observed from intestine at 7h. Complete dissociation and release of drug was observed at 24h in colon due to anaerobic microbial rich environment. Results drawn from Scintigraphy images indicate that radiolabeled (99m)Tc-Tinidazole tablet transit through upper part of GI without disintegration. Hence the developed matrix tablet may have a role in treatment of intestinal infection caused by anaerobic bacteria.

Acute and sub acute toxicity and efficacy studies of Hippophae rhamnoides based herbal antioxidant supplement.

OBJECTIVES: Present study was carried out to evaluate acute and subacute toxicity and efficacy of Seabuckthorn (Hippophae rhamnoides) based herbal antioxidant supplement (HAOS). MATERIALS AND METHODS: In vivo toxicity studies were performed in male balb 'C' mice by oral administration. Acute toxicity study was done at doses ranging from 2000 to 10 000 mg/ kg while in subacute studies, HAOS was given at doses of 2000, 4000, and 8000 mg/kg body weight. Animals were observed for any toxic sign and symptoms periodically. At completion of study animals were sacrificed; their hematological, biochemical parameters were analyzed and histopathology of vital organs was done. In vivo efficacy studies in human volunteers were done and the levels of vitamin A and Vitamin C in blood samples were analyzed in comparison to a similar commercially available formulation. RESULTS: No mortality and any clinical signs of toxicity were found in HAOS administered group of animals. There were no significant alterations in hematological and biochemical parameters. Histopathological analysis of vital organs showed normal architecture in all the HAOS administered groups. Human studies showed an increase of 32% and 172% in Vitamin A and Vitamin C levels respectively in term of bioavailability. CONCLUSION: The data obtained indicate no toxicity of this antioxidant supplement up to the highest dose studied. Efficacy in terms of increased bioavailability of vitamin A and C in human volunteers indicates the clinical usefulness of the supplement.