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.

Development and Gamma Scintigraphy Study of Trigonella foenum-graecum (Fenugreek) Polysaccharide-Based Colon Tablet.

The major concern with the use of some synthetic excipients is their safety towards biological tissues, hence influencing the reliability of products. With the aim to minimize dependency on highly toxic synthetic excipients, the present study was designed to deliver metronidazole (MNZ) into the colonic region for localized treatment of amoebiasis using natural polysaccharide-based drug delivery. Compression-coated tablets were prepared using water extractable natural polysaccharide from Trigonella foenum-graecum (FG). Physical properties of the tablets were evaluated and dissolution study was performed at pH 1.2, 6.8, and 7.4 with rat cecal material. Results indicate that all batches demonstrated pH-dependent drug release and prevented release into the stomach, allowing traces into the intestine and highest availability into the colon. A significant correlation (r2 = 0.975) was found between the coating levels of extracted polysaccharide and lag time release of drug. Gamma scintigraphy images of in vivo study conducted on human volunteers showed a small intestinal transit time, i.e., 3-5 (4.2 ± 0.4) h and confirmed that the tablets reached the colon within 6-8 h. The present study revealed that the FG polysaccharide-based double compression tablets may be promising colon-specific drug carriers with reduced toxic effects of commonly used synthetic excipients.

Formulation development and evaluation of nifedipine as pylorospasm inhibitor.

INTRODUCTION: In this study, different nifedipine-loaded formulations were prepared to treat pylorospasm, a sphincter muscle disorder characterized by delayed gastric emptying process. The efficacy of formulation was evaluated in patients by subjective assessment, gamma scintigraphic approaches, and confocal microscopy. METHODS: Nifedipine-loaded different formulations such as sucrose bead, pellets, and microparticles (slugging method, ionotropic gelation, and chemical denaturation) were designed. The studies were performed on 50 subjects, of which 30 subjects were treated with optimized nifedipine loaded microcapsules while 20 subjects were given capsule becosule-Z as a control. The efficacy of formulation was assessed by comparing symptoms like dyspepsia, abdominal pain, abdominal fullness, poor appetite, nausea, vomiting, and irregular motion. The effectiveness of formulation was also assessed by gamma scintigraphic studies by determining the rate of emptying of a radioactivity labeled standard meal from patients' stomach into the duodenum. Confocal microscopy was used to assess targeting potential of developed formulation. RESULTS: Drug-loaded alginate-chitosan microcapsules were found to be satisfactory, in terms of controlled drug release, surface morphology, and bioadhesive properties and thus selected for in vivo studies. Clinical studies revealed the efficacy of formulation in abolishing various GI symptoms at high altitude. Associated symptoms such as dyspepsia, abdominal pain, poor appetite, nausea, vomiting, and irregular motion were recovered by 75, 62, 76.5, 86.7, 85.7, and 37.5%, respectively in nifedipine-treated patients. In comparison, 73.7, 40, 33.3, 40, 20, and 0% recoveries were observed in patients given control treatment only. Gamma Scintigraphic studies in lab also revealed 2.425 ± 0.245 (p < .05) times improvement in gastric emptying rate in patients with diabetic gastroparesis. Confocal analysis showed better targeting and penetration in pyloric region when formulation was administered in form of high-density microcapsules. CONCLUSIONS: Results strongly suggest that nifedipine loaded mucoadhesive formulation has a targeting potential which accelerates gastric emptying process in gastroparesis patients, and thus the formulation might prove useful as a potent prokinetic agent.

Mucoadhesivity Characterization of Isabgol Husk Mucilage Microspheres Crosslinked by Glutaraldehyde.

The microspheres of Isabgol husk were prepared by emulsification-crosslinking technique and the gastrointestinal transition behavior of the formulation was studied by gamma scintigraphy. The impact of different process variables such as amount of glutaraldehyde, concentration of Isabgol husk and temperature was studied on surface morphology and mucoadhesion. In vitro mucoadhesive testing of formulations was performed by determination of zeta potential, mucus glycoprotein assay and mucus adsorption isotherms. The effect of feeding on retention of microspheres in the gastrointestinal track (GIT) was studied in albino rabbits by gamma scintigraphy study. The results indicated the formation of microspheres as observed by scanning electron microscopy. The smooth and round surfaces of microspheres were obtained on increasing Isabgol husk and glutaraldehyde amount. The positive zeta potential of all formulations indicated the electrostatic interaction as a mechanism of mucoadhesion between the mucus of GIT membranes and the microspheres surfaces. The influence of electrostatic interaction on mucoadhesion of microspheres was again ascertained when the mucin equilibrium adsorption on preparations indicated well fitness in Langmuir and Freundlich adsorption isotherms. During gamma scintigraphy, the stability of (99m)Tc-sodium pertechnetate was found 98.82% at pH 6.8 and 96.78% at pH 7.2, respectively. It indicated the minimal leaching of bound radionuclide from microspheres during gastrointestinal transition as observed in gamma scintigraphic images of the rabbits. The microspheres retained in GIT even after 24 hrs of oral administration. The results indicated the applicability of Isabgol husk mucilage in the development of mucoadhesive microspheres.

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.

Ameliorative potential of alpha-ketoglutaric acid (AKG) on acute lung injuries induced by ammonia inhalation in rats.

INTRODUCTION: Toxicants such as ammonia, if inhaled, can damage respiratory tract leading to acute lung injury and pulmonary edema. Besides being a possible threat for the workers in chemical industry, easy availability and the toxic nature of ammonia may be used by terror groups for inflicting mass casualty among vulnerable population. In the present study, we have evaluated the therapeutic efficacy of alpha-ketoglutarate (AKG) to mitigate acute effects of ammonia on lung structure and antioxidant status in experimental animals. METHODS: Acute lung injury (ALI) models were developed by inhalation of aerosols of liquid ammonia in male Sprague Dawley rats. AKG (5%) respiratory fluid was inhaled by nebulization once daily for 5 days. Animals were euthanized and their blood samples were collected for hematology and serum biochemistry analysis. Total cell count, total protein (TP), lactate dehydrogenase (LDH), antioxidant enzyme activity (CAT, SOD, GSH), and malonaldialdehyde (MDA) formation were measured in bronchoalveolar lavage (BAL) fluid. RESULTS: Treatment with AKG showed significant lung protection by lowering the levels of total cell count, TP, LDH, superoxide dismutase (SOD), and MDA in BAL fluid. There was a marked increase in catalase (CAT) and glutathione (GSH) content of BAL fluid post-AKG inhalation. Histopathology of lung tissue correlated with cellular and biochemical findings indicate therapeutic efficacy of AKG against ammonia-induced lung injuries. CONCLUSIONS: The data suggest a possible therapeutic role of AKG inhalation against ammonia-induced structural and inflammatory changes in the lung.

Efficacy of indigenously developed single vial kit preparation of 99mTc-ciprofloxacin in the detection of bacterial infection: an Indian experience.

OBJECTIVE: To investigate the diagnostic efficacy of indigenously developed single vial kit preparation of Tc-ciprofloxacin (Diagnobact) for the detection of orthopedic infections. METHODS: Seventy-seven patients [25 with clinical suspicion of diabetic foot osteomyelitis (DFOM), 25 with orthopedic device-related infection (ODRI) and 27 with tubercular bone infection] underwent three-phase Tc-methylenediphosphonate bone scintigraphy followed by static Tc-ciprofloxacin imaging at 1, 4 and 24 h. Imaging (anterior and posterior views) was performed under a dual-head gamma-camera using a low-energy, high-resolution, parallel-hole collimator. The lesion-to-background ratio (LBR) of the radiotracer was calculated on the static isotime Tc-ciprofloxacin images using semiquantitative analysis. Scintigraphic (Diagnobact) results were compared with the histopathological and/or culture/PCR analysis as a gold standard. RESULTS: The mean LBR of the radiotracer (Tc-ciprofloxacin) in the positive scans (n=29; 16 ODRI, 13 DFOM) was > or =2.0 at 1 h postinjection and remained consistent till 24 h. In contrast, the mean LBR in the negative scans (n=21; 12 DFOM, nine ODRI) was < or =1.5 at 1 h and declined significantly (P<0.05) at 24 h. The observed trend in the mean LBR in positive (n=18) and negative (n=9) scans for tubercular osteomyelitis was identical to that seen in the nontubercular bacterial infections. CONCLUSION: The management protocol for patients with suspected bony infection may include a three-phase bone scan followed by Tc-ciprofloxacin scan. An LBR of > or =2.0 at 1 h that remained consistent till 24 h on Tc-ciprofloxacin scan is indicative of active bacterial infection. However, resistance to ciprofloxacin at the bacterial cell membrane may be a limitation of this technique.

Diagnosis, characterisation and evaluation of treatment response of frostbite using pertechnetate scintigraphy: a prospective study.

No large prospective study is available on use of a radionuclide method to assess frostbite and its response to conservative treatment. Recently, a large retrospective study using two-phase bone scintigraphy suggested that non-uptake (or low uptake) in frostbite lesions in the blood pool or bone phase had a strong correlation with the subsequent need for amputation. In the present study, we performed early blood pool scintigraphy with technetium-99m pertechnetate in 20 patients (10-180 days after frostbite injury; 71 clinical lesions) referred for a topical treatment protocol for mild to moderately severe frostbite, and in 22 asymptomatic controls. The aims of the study were to define the "normal" microcirculation of the hands and feet, to characterise the appearances of frostbite lesions on scintigraphy and correlate these with the clinical presentation, and to evaluate the usefulness of scintigraphy for assessing the treatment response. Six patients were "fresh", 12 had been undergoing conservative treatment (topical homeopathic) for several weeks and two had permanent fibrotic hand phalanges. Nine patients on treatment underwent serial scintigraphy a total of 22 times. Eleven patients were imaged only once, including the two with permanent fixed defects. Three distinct physiological microcirculation patterns were evident in control hands or feet: right- or left-handedness (seven subjects), subclinical inflammatory foci correlating with callosity or pressure points (36 lesions) and distinctly increased pooling of radiotracer at the thenar or hypothenar region (eight subjects). In frostbite patients, 128 lesions (48 inflammatory, 80 ischaemic) were seen on the scan. This number included all 71 lesions identified clinically, the rest being subclinical. Subclinical frostbite lesion as an entity has not been described previously. Microvasculature of normal muscle groups (in the hands, elbow or feet) was shown on scintigraphy to improve after topical treatment. The treatment resulted in improved or normalised perfusion scan in 25 of 45 ischaemic segments with matching clinical improvement, and reduction or normalisation of uptake in inflammatory lesions (n=30). The data confirm the vasodilator and anti-inflammatory action of the topical preparation, and the sensitivity of the radionuclide method in monitoring treatment response. In contrast to the previous findings that non-uptake on a scan performed 2 or more weeks after exposure correlates with the need for amputation, none of the 80 ischaemic lesions in our series required amputation while 60% showed improvement or normalisation in microvascular blood flow even though they were 10-180 days old. Our findings suggest that moderate to severe frostbite lesion can be classified as having infarcted, ischaemic or hibernating (viable) tissue, similar to the classification employed when using myocardial scintigraphy. Absence of uptake even after the initial 10 days does not necessarily indicate infarction and the need for amputation as many such lesions retain potential for vasodilation and recovery.