Biotechnological formation of dairy flavor inducing δ-lactones from vegetable oil.

Agroscope Culture Collection was screened to identify bacterial strains effective in production of dairy flavor inducing lactones using grapeseed oil as a substrate. Lentilactobacillus parafarraginis FAM-1079, Lactococcus lactis subsp. lactis FAM-17918, and L. lactis subsp. lactis biovar diacetylactis FAM-22003 showed the most efficient formation of targeted δ-lactones. The application of sublethal heat stress significantly increased target lactone production. The most profound improvement was for L. lactis subsp. lactis biovar diacetylactis where δ-octadecalactone generation was improved by factor of 9. The pre-fermentation step as well as growth phase in which bacteria are harvested did not have a significant impact on lactones yield. The lactone production process from vegetable oil developed in this study offers a new way of developing a natural flavor ingredient for incorporation into plant-based products.

Sildenafil efficacy in erectile dysfunction secondary to spinal cord injury depends on the level of cord injuries.

To evaluate the efficacy of sildenafil in the treatment of neurogenic erectile dysfunction (ED) secondary to upper motor neuron (UMN) and lower motor neuron (LMN) spinal cord injury (SCI). After taking consents 105 patients suffering from ED were enrolled in this prospective study. Seventy-two patients had signs and symptoms of UMN and 33 patients had signs and symptoms of LMN or mixed (UMN and LMN) spinal cord injuries. The patients took 50-100 mg sildenafil or placebo tablet at least 45 min before sexual intercourse. Based on a IIEF questionnaire, success in achieving erection adequate for sexual intercourse was compared between sildenafil and placebo groups in UMN and non-UMN spinal cord injuries. In patients with UMN disease, sildenafil was effective in 82% of patients and its efficacy was statistically higher than placebo (82 vs. 25%, p < 0.05). Twenty-eight per cent of patients with non-UMN disease had a favourable response to sildenafil that was not statistically different from placebo. Sildenafil seems more effective in the treatment of neurogenic ED secondary to UMN spinal cord injury compared with that secondary to LMN injury. Actually, its efficacy on LMN injuries does not seem different from placebo and administration of this treatment may not be effective in spinal cord injury which has caused LMN symptoms.

Evaluation of selected micronized poloxamers as tablet lubricants.

The primary objective of this study was to compare the lubrication properties of micronized poloxamer 188 (Lmicrotrol micro 68) and micronized poloxamer 407 (Lmicrotrol micro 127) with certain conventional lubricants such as magnesium stearate and stearic acid. The secondary objective was to use these micronized poloxamers as water-soluble tablet lubricants in preparation of effervecsent tablets. The results showed that these micronized poloxamers have superior lubrication properties compared with stearic acid, with no negative effect on tablet hardness, friability, disintegration, or dissolution. Moreover, lubricant mixing time had no significant effect on tablet properties when poloxamers were used as lubricants. Effervescent tablets also were produced successfully using micronized poloxamers as lubricants. The micronized poloxamers had a better lubrication effect in comparison with that of water-soluble lubricant l-leucine.

Patients with History of Colonoscopy Are Less Likely to Achieve High Quality Preparation After Implementing Split-Dose Bowel Preparation.

BACKGROUND: Anecdotally, we observed that patients who had previous colonoscopies were less likely to follow newly implemented split-dose bowel preparation (SDBP) instructions. We investigated whether the indication for colonoscopy is an independent factor for achieving high quality bowel preparation among patients asked to follow SDBP. METHODS: We performed a retrospective study of data from 1478 patients who received outpatient colonoscopies in 2014 (the year of SDBP implementation) at our Veterans Affairs Medical Center. We collected information related to demographics and factors known to affect bowel preparations. Reasons for colonoscopy were dichotomized into surveillance (previous colonoscopy) vs. non-surveillance (positive occult blood test or screening). Bowel preparation quality was scored using the Boston Bowel Preparation Scale (BBPS), and was categorized as either excellent vs. not excellent (BBPS≥7 vs. BBPS<7), or adequate vs. inadequate (BBPS≥6 vs. BBPS<6). RESULTS: Bowel preparation quality was excellent in 60% of colonoscopies and adequate in 84% of colonoscopies. Thirty-six percent (535) were surveillance colonoscopies. In multivariate logistic regression analysis, more patients in the non-surveillance group achieved excellent (OR 0.8 ; 95% CI [0.7-0.8], P <0.0001) and adequate (OR 0.8 ; 95% CI [0.7-0.9], P <0.006) bowel preparation than did patients in the surveillance group. CONCLUSION: Patients with a prior colonoscopy might not follow the split-dose bowel preparation instructions. Educational interventions emphasizing the benefits of SDBP in this group of patients may help ensure compliance and prevent the habitual use of day-before preparations.

Evaluation of polyvinyl acetate dispersion as a sustained release polymer for tablets.

Kollicoat SR 30D is a unique 30% aqueous dispersion of polyvinvyl acetate stabilized by polyvinyl-pyrrolidone intended for preparation of sustained release products. Detailed evaluation of this polymer dispersion as a sustained release coating for active pharmaceutical ingredients of two diverse classes of drugs was studied. A water insoluble drug (ibuprofen) and a water soluble drug (ascorbic acid) were selected as model active drugs. Ibuprofen was granulated using a GPCG-1 fluid bed processor prior to tableting, to improve the particle size and particle flow properties. In this process a 2(3) factorial design was implemented to evaluate the optimum process parameters such as spray rate, inlet air temperature and the inlet air velocity. The statistical model selected was Y(ijkl) = mu + tau(i) + beta(j) + theta(k) + (taubeta)ij + (betatheta)jk + (tautheta)ik + (taubetatheta)ijk + epsilon(ijkl). The factorial design showed that the spray rate, inlet air temperature, and inlet air velocity had a significant effect (p value <0.05) on the particle size. Significant improvement was observed in the flow properties of the granules. The granules were coated with Kollicoat SR30D dispersion using top spray method in the fluid bed processor. The dissolution studies showed that the release of ibuprofen decreased with an increase in the coating levels of Kollicoat SR 30 D. In the case of ascorbic acid, preparation of sustained release coated commercial granules was not possible due to the difficulty in coating a highly soluble drug particle. However, the coated granules when compressed into tablets showed some sustainability. Ibuprofen tablets manufactured with coated granules with a 15 g polymer for 300 g batch showed dissolution parameters of t50 and t90 at 4.2 hr and 7.5 hr, respectively. An approximate zero-type of release was observed when the polymer content was increased to 45 g for 300 g batch. Ascorbic acid tablets made with coated commercial granules having a total polymer content of 45 g per a 500 g batch showed an average dissolution t50 and t90 at 1.0 hr and 4.55 hr, respectively. When the total polymer content was increased to 60 g, per 500 g, the average dissolution t50 and t90 delayed to 1.40 hr and 7.20 hr, respectively.

Breast cancer growth is inhibited by vasoactive intestinal peptide (VIP) hybrid, a synthetic VIP receptor antagonist.

Breast cancer vasoactive intestinal peptide (VIP) receptors were characterized. Using in vitro autoradiographic techniques, 125I-labeled VIP bound with high affinity to breast biopsy sections. 125I-labeled VIP bound specifically to give breast cancer cell lines examined using receptor-binding techniques. Specific 125I-labeled VIP binding to MDA-MB-231 cells was inhibited with high affinity by VIP and pituitary adenylate cyclase-activating polypeptide (IC50, = 2 nM) and with moderate affinity by the VIP hybrid (IC50 = 0.5 microM). VIP elevated the cAMP in a dose-dependent manner, and VIP hybrid (10 microM) inhibited the increase in cAMP caused by VIP. Using Northern blot analysis, VIP (10 nM) stimulated c-fos and c-myc mRNA, and the increase caused by VIP was reversed by the VIP hybrid. The VIP hybrid inhibited breast cancer growth in vitro and in vivo using nude mice bearing breast cancer xenografts. These data suggest that the VIP hybrid is a breast cancer VIP receptor antagonist.

Evaluation of urinary abnormalities in nephrolithiasis patients from Marathwada region.

Urinary abnormalities were evaluated in 100 renal stone patients with first episode of renal stone having age 22 to 45 years from both sex and compared to 100 normal healthy control group having same age group from both sex. Twenty-four hours urinary oxalate, calcium, uric acid, sodium, magnesium, phosphorus and citrate were estimated. The urinary pH was also determined. In stone formers urinary oxalate, calcium, sodium and uric acid excretions were significantly higher when compared with control group. Whereas citrate, phosphate and magnesium excretion were significantly lower in stone formers when compared with control.The pH of urine in stone formers was lower than the controls. High dietary intake of purine rich diet causes elevated excretion of uric acid, which leads to calcium oxalate crystal formation and precipitation. Other risk factors such as urinary oxalate, calcium also related to formation of renal calculi.Hypocitraturia is the main cause of renal calculi along with hypomagnesiuria and hypophosphaturia in the patient of Marathwada region. On the basis of urinary abnormalities further stone formation in the patient can be prevented by dietary modifications.

Ophthalmic drug delivery systems--recent advances.

Eye-drops are the conventional dosage forms that account for 90% of currently accessible ophthalmic formulations. Despite the excellent acceptance by patients, one of the major problems encountered is rapid precorneal drug loss. To improve ocular drug bioavailability, there is a significant effort directed towards new drug delivery systems for ophthalmic administration. This chapter will focus on three representative areas of ophthalmic drug delivery systems: polymeric gels, colloidal systems, cyclodextrins and collagen shields. Hydrogels generally offer a moderate improvement of ocular drug bioavailability with the disadvantage of blurring of vision. In situ activated gel-forming systems are preferred as they can be delivered in drop form with sustained release properties. Colloidal systems including liposomes and nanoparticles have the convenience of a drop, which is able to maintain drug activity at its site of action and is suitable for poorly water-soluble drugs. Among the new therapeutic approaches in ophthalmology, cyclodextrins represent an alternative approach to increase the solubility of the drug in solution and to increase corneal permeability. Finally, collagen shields have been developed as a new continuous-delivery system for drugs that provide high and sustained levels of drugs to the cornea, despite a problem of tolerance. It seems that new tendency of research in ophthalmic drug delivery systems is directed towards a combination of several drug delivery technologies. There is a tendency to develop systems which not only prolong the contact time of the vehicle at the ocular surface, but which at the same time slow down the elimination of the drug. Combination of drug delivery systems could open a new directive for improving results and the therapeutic response of non-efficacious systems.

(N-stearyl, norleucine17) VIP hybrid inhibits the growth of pancreatic cancer cell lines.

The effects vasoactive intestinal peptide (VIP) antagonists were investigated on pancreatic cancer cell lines. (N-Stearyl, Norleucine17) VIP hybrid ((SN)VIPhyb) inhibited 125I-VIP binding to human Capan-2 cells with an IC50 value of 0.01 microM whereas VIP hybrid had an IC50 value of 0.2 microM. By RT-PCR and Northern blot, VPAC1 receptor mRNA was detected in CAPAN-2 cells. One microM (SN)VIPhyb and 10 microM VIPhyb inhibited the ability of 30 nM VIP to elevate cyclic AMP and increase c-fos mRNA. (SN)VIPhyb, 1 microM inhibited the clonal growth of CAPAN-2 cells in vitro. In vivo, (SN)VIPhyb (10 microg/day s.c.) inhibited CAPAN-2 xenograft growth in nude mice. These results indicate that (SN)VIPhyb is a pancreatic cancer VPAC receptor antagonist.

Indomethacin reduces lung adenoma number in A/J mice.

The effects of indomethacin on A/J mice were investigated. The non-steroidal antiinflammatory drug (NSAID) indomethacin reduced significantly the number of lung adenomas 3, 4 or 8 months after urethane injection by 28, 30 and 29% respectively. The density of apoptotic cell bodies increased 2.9-fold in the lung adenomas of A/J mice treated with indomethacin. By immunocytochemistry, COX-2 immunoreactivity was present in the cytosol of lung adenomas, and in epithelial cells lining the bronchioli and bronchus as well as type 2 alveolar cells. COX-1 immunostaining was similar to that of COX-2 in the lungs of urethane-injected mice treated with or without indomethacin. By RT-PCR, COX-1 and COX-2 PCR products were present in mouse lung adenomas, alveoli and bronchioli. These results suggest that indomethacin may inhibit COX-1 and COX-2 in the A/J mouse lung resulting in reduced adenoma formation.

Codiffusion of propylene glycol and dimethyl isosorbide in hairless mouse skin.

The in vitro percutaneous fluxes of propylene glycol (PG), cis-oleic acid (OA) and dimethyl isosorbide (DI) were determined and their effect on nifedipine (N) flux and lag time evaluated. PG, OA and DI flux through hairless mouse (HM) skin was measured in vitro by beta-scintigraphy and N permeation was measured by HPLC under finite and infinite dose conditions. Evaluation of each of the solvents separately showed that pure DI possessed the inherent ability to traverse the skin (12% in 24 h). For the tested formulation after 24 h, 57% of the PG and 40% of the DI had permeated across the skin with nearly linear permeation between 4 and 18 h and the relative order of permeation was PG > DI > N. DI permeation was further aided in the presence of PG and OA. N flux was dependent on concomitant solvent permeation. Over a 24-h test period a dose dependent response was observed for N, with 4.9-15.6 mg of N delivered from the lowest and highest doses, respectively, and the highest dose yielding zero-order flux of 146 (g/h per cm2).

Binding study of sulfonylureas and phenothiazines to bovine serum albumin using difference spectrophotometry.

2-(4'-Hydroxybenzeneazo)benzoic acid is a spectrophotometric probe which shows absorption spectrum changes upon binding to protein. Difference absorption spectra of this probe were used as an indirect measurement of the binding of selected sulfonylurea and phenothiazine drugs to bovine serum albumin. The results obtained using the spectrophotometric probe were similar to data obtained from other methods, especially fluorescent methods. Of the four sulfonylureas studied, tolbutamide showed the highest binding affinity, followed by glyburide, glipizide, and acetohexamide, in that order. The data collected for phenothiazine drugs indicated that chlorpromazine has the highest affinity, followed in order by trifluoperazine, perphenazine, fluphenazine, and promazine. Correlation of these results with chemical composition indicated that the interaction of phenothiazine drugs with bovine serum albumin was of a hydrophobic nature.

Binding study of tetracyclines to human serum albumin using difference spectrophotometry.

The binding of several tetracyclines to human serum albumin was studied using difference spectrophotometry and a spectrophotometric probe, 2-(4'-hydroxybenzeneazo)benzoic acid. Difference spectra observed for the interaction between the probe and human serum albumin were similar to probe-bovine serum albumin spectra but were less intense for a given concentration of probe and did not reach saturation as quickly. Difference spectra for the tetracyclines were dependent on the characteristics of the ring substituents. More hydrophobic substituents on the D and C rings tended to give more intense difference spectra, but charge-transfer complexing may also have been involved since methacycline with a methylene group in the 6-position showed the most intense spectra of the compounds studied. Solvent perturbation, pH, and urea studies tended to confirm that something other than hydrophobic binding of the tetracyclines was involved. Drug-probe displacement studies showed that methacycline gave the greatest probe displacement followed by doxycycline, chlortetracycline, oxytetracycline, and tetracycline. This order of displacement of the anionic probe indicates that both hydrophobic and charge-transfer binding are involved. Experiments with calcium ion and ethylenediaminetetraacetic acid showed that the difference spectra obtained with the tetracyclines and human serum albumin were not the result of metallic bridge-chelate formation.

Correlation of aspirin excretion with parameters from different dissolution methods.

The cumulative urinary excretion of four different aspirin products (two tablets, a capsule, and a timed-release tablet) was determined in a crossover study using five subjects. Comparison of in vivo results showed a significant difference in cumulative urinary excretion levels at only 1 hr. The excretion from the two regular tablets was significantly different from the timed-release tablet, but the capsule showed no significant difference from the other three products. Each product was tested in the USP, Levy beaker, and the regular and large magnetic basket dissolution apparatus. Analysis of variance of the in vitro results showed a significant difference between the aspirin products and the dissolution methods at selected times. In vitro comparison with in vivo results for the four products showed that a regression analysis can be used to determined which dissolution methods produce a significant correlation with urinary excretion.

Development and evaluation of nasal formulations of ketorolac.

Ketorolac tromethamine is a potent non-narcotic analgesic with moderate anti-inflammatory activity. Clinical studies indicate that ketorolac has a single dose efficacy greater than morphine for postoperative pain and has excellent applicability in the emergency treatment of pain. Due to incomplete oral absorption of ketorolac, several approaches have been tried to develop a nonoral formulation in addition to injections, especially for the treatment of migraine headache. The aim of our study was to develop a nasal formulation of ketorolac with a dose equivalent to the oral formulation. A series of spray and lyophilized powder formulations of ketorolac were administered into the nasal cavity of rabbits, and their pharmacokinetics profiles were assessed. The spray and powder formulations were compared through their pharmacokinetics parameters and absolute bioavailability. Drug plasma concentration was determined using solid phase extraction, followed by an HPLC analysis. Nasal spray formulations were significantly better absorbed than powder formulations. A nasal spray formulation of ketorolac tromethamine showed the highest absorption with an absolute bioavailability of 91%. Within 30 min of administration, the plasma concentration was comparable to that resulting from an intravenous injection. The absolute bioavailability of a solution of ketorolac acid was 70%. Apparently, the dissolution of ketorolac acid into the mucous layer limits its absorption. There were no significant differences in absorption between different powder formulations. Even the reduction of particle size from 123 microm to 63 microm did not indicate better absorption of ketorolac tromethamine from powder formulations. Interestingly, the absolute bioavailability of ketorolac tromethamine from a powder formulation is only 38%, indicating that the drug may not be totally released from the polymer matrix before it is removed from nasal epithelium by mucociliary clearance.

The influence of the enhancer dimyristoylphosphatidylglycerol and formulation factors on the nasal absorption of salmon calcitonin.

The objective of this investigation was to study the effect of the phospholipid dimyristoylphosphatidylglycerol (DMPG) on the intranasal absorption of the polypeptide salmon calcitonin (sCT). DMPG was included as an absorption enhancer for salmon calcitonin in a 0.03 M acetate buffer at pH 4 in a nasal spray formulation. The absorption of sCT was studied as a function of NaCl concentration from 0.045 to 0.3 M. Serum calcitonin was determined using a double-antibody radioimmunoassay (RIA). The presence of the phospholipid demonstrated a significant difference in the intranasal bioavailability of salmon calcitonin. The results showed that DMPG enhanced the nasal absorption of sCT by approximately twofold at a salt concentration of 0.045 M. However, higher salt concentrations in the formulation demonstrated a decrease in the absorption-enhancing effect of DMPG. The effect of DMPG on the calcium-lowering effect of sCT was also studied. There was no significant difference in the hypocalcemic activity of sCT in the presence of DMPG. In addition, it was found that increasing the viscosity of those formulations containing DMPG did not further increase the nasal bioavailability of sCT.

Development of a new non-surgical perfusion technique for evaluation of nasal drug delivery.

A new non-surgical perfusion technique was developed to evaluate nasal absorption using the rabbit as an animal model and insulin as a model drug. For these studies 20 ml of insulin solution (10 U/kg + 0.05% Na taurocholate) was perfused for 3.5 hours at a rate of 10 ml/hr. Spray formulations containing different levels of insulin (1.25, 2.5, 5 and 10 U/kg) and sodium taurocholate (0.05 and 1.0%) were evaluated in the same animal model. Insulin loaded polyacrylic acid microparticles were administered in 1% gel formulation to determine the comparative effect of insulin. The absorption of insulin was measured by glucose reduction. Pharmacodynamic parameters were determined relative to subcutaneously injected insulin (0.25 U/kg). The new non-surgical perfusion technique proved to be easier to control and more reproducible than the formerly used perfusion model while providing comparable results. The maximum relative absorption was observed for the 1.25 U/kg spray containing 1% NaTC. The polyacrylic acid gel formulation containing insulin loaded microparticles (10 U/kg) resulted in lower hypoglycemic effect compared to the spray formulations and subcutaneous injection.

Long-term results of hepatitis B immunoglobulin and lamuvidine for hepatitis B prophylaxis after liver transplantation.

PURPOSE: Recurrence of hepatitis B virus after a liver transplantation (OLT) is a risk factor affecting graft and patient survivals. Short-term hepatitis B virus reactivation rates after OLT range between 3% and 15%. Using combination prophylaxis, the outcomes of OLT among patients with liver disease related to hepatitis B virus have improved to levels comparable to those whose disease is not related to hepatitis B virus. MATERIALS AND METHODS: Since September 2001, we performed 288 OLT in 282 patients including 74 who had liver failure related to hepatitis B virus among whom 58 were followed for >12 months and analyzed retrospectively. Our protocol included lamivudine (100 mg orally per day beginning the day after surgery) and hepatitis B immunoglobulin (10,000 IU IV during the anhepatic phase, 2000 IU/d IV during the first week after surgery, 2000 IU IV/month from postoperative months 1 to 12). Using our protocol, the anti-hepatitis B surface antibodies (HBsAb) serum titer was maintained up to 100 IU/mL. The female:male ratio was 11:47. The mean age of patients was 43±12.8 years. RESULTS: Five patients died of causes unrelated to hepatitis B virus. At the time of death, their hepatitis B surface antigens were negative, and serum titers of anti-HBsAb were 45, 35.3, 56.4, 79.6, and 123 IU/mL. Mean follow-up was 46.5±18.9 months (range, 12-79). The hepatitis B surface antigen became positive in 4 patients; the remaining 49 had no evidence of hepatitis B surface antigen. In 18 patients, serum titer of anti-hepatitis B surface antigen was 0; in the remaining 31 patients, it was 69.2±133 IU/mL. CONCLUSION: Our combination protocol with hepatitis B immunoglobulin and lamivudine is a safe, cost-saving, and effective treatment for hepatitis B virus prophylaxis after liver transplantation.