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Objective(s): In this study, a stable bear bile-loaded pH sensitive in-situ eye drop gel was prepared for sustain delivery and enhanced therapeutic application. Materials and Methods: Bear bile-loaded in-situ ocular gels with different Carbopol/Hydroxypropyl methylcellulose (HPMC) ratios were prepared and their stability was tested in PBS at a series of pH at 40 °C. The morphology was observed by SEM examination and rheology was observed by Rheometer equipped with a 60-mm cone-plate at apex angle of 1°. Gel erosion and release kinetics of Tauroursodeoxycholic acid (TUDCA) was determined by HPLC. While, the in vivo dwelling time was obtained after administering the fluorescent-loaded gel in ocular disease-free New Zealand rabbits. Finally, biocompatibility and toxicity was observed by irritation test and H&E staining of eye-ball tissues, respectively. Results: The bear bile-loaded in-situ ocular gel showed excellent stability at different pH (pH 5.0, 5.5, 6.0, 6.5, 7.0 and 8.0) up to 5 days, and bear bile extract significantly attenuated the gelling ability of the in-situ gel. The viscosity of in-situ gels formulation was decreased with increase in shear rate (0.01 to 100 s-1), and morphological examination of freeze-dried preparation showed three-dimensional reticular structure at physiological pH. The in-situ ocular gel exhibited promising sustained drug release up to 160 min in vitro, and showed prolonged retention time up to 3-folds in vivo. Finally, the biocompability data confirmed that the formulation did not induce any toxic effects and was completely compatible with eye tissues. Conclusion: pH sensitive in-situ ocular gel provides new research opportunities to efficiently treat eye diseases. [ABSTRACT FROM AUTHOR]

Signal transducer and activator of transcription (STAT) proteins represent novel therapeutic targets for the treatment of cancer. In particular, STAT-3 serves critical roles in several cellular processes, including the cell cycle, cell proliferation, cellular apoptosis and tumorigenesis. Persistent activation of STAT-3 has been reported in a variety of cancer types, and a poor prognosis of cancer may be associated with the phosphorylation level of STAT-3. Furthermore, elevated STAT-3 activity has been demonstrated in a variety of mammalian cancers, both in vitro and in vivo. This indicates that STAT-3 serves an important role in the progression of numerous cancer types. A significant obstacle in developing STAT-3 inhibitors is the demonstration of the antitumor efficacy in in vivo systems and the lack of animal models for human tumors. Therefore, it is crucial to determine whether available STAT-3 inhibitors are suitable for clinical trials. Moreover, further preclinical studies are necessary to focus on the impact of STAT-3 inhibitors on tumor cells. When considering STAT-3 hyper-activation in human cancer, selective targeting to these proteins holds promise for significant advancement in cancer treatment. In the present study, advances in our knowledge of the structure of STAT-3 protein and its regulatory mechanisms are summarized. Moreover, the STAT-3 signaling pathway and its critical role in malignancy are discussed, in addition to the development of STAT-3 inhibitors in various cancer types. [ABSTRACT FROM AUTHOR]

The purpose of this study was to introduce the technology for the development of rate-controlled oral drug delivery system to overcome various physiological problems. Several approaches are being used for the purpose of increasing the gastric retentive time, including floating drug delivery system. Gastric floating lisinopril maleate and metoprolol tartrate bilayer tablets were formulated by direct compression method using the sodium starch glycolate, crosscarmellose sodium for IR layer. Eudragit L100, pectin, acacia as sustained release polymers in different ratios for SR metoprolol tartrate layer and sodium bicarbonate, citric acid as gas generating agents for the floating extended release layer. The floating bilayer tablets of lisinopril maleate and metoprolol tartrate were designed to overcome the various problems associated with conventional oral dosage form. Floating tablets were evaluated for floating lag time, drug contents and in-vitro dissolution profile and different kinetic release models were applied. It was clear that the different ratios of polymers affected the drug release and floating time. L2 and M4 showed good drug release profile and floating behavior. The linear regression and model fitting showed that all formulation followed Higuchi model of drug release model except M4 that followed zero order kinetic. From the study it is evident that a promising controlled release by floating bilyer tablets of lisinopril maleate and metoprolol tartrate can be developed successfully. [ABSTRACT FROM AUTHOR]

The present study is about to prepare stable cream of water-in-oil emulsion containing extracts of Crocus sativus against its base (without extracts) taken as control, to determine its stability on different storage conditions and effects on skin moisture contents and transepidermal water loss. The formulation contains 3% Crocus sativus (Saffron) concentrated extracts, and the base containing no extract, were formulated. Different stability tests were done on samples, which placed at 8 °C, 25 °C, 40 °C and 40 °C with 75% relative humidity, for 4 week period. These formulations (Creams) were applied on the cheeks of human volunteers for 8week period. To evaluate any effect produced by these formulations different skin parameters were monitored every week. The significant results of this study explored the fact that water-in-oil emulsion topical cream of saffron formulated from Crocus sativus extract has absolute physical stability at different storage conditions. The increase in skin moisture contents and changes in transepidermal water loss were significant (p<0.05) with respect to base and formulation respectively. Topical cream of Crocus sativus showed significant moisturizing effects on human skin. [ABSTRACT FROM AUTHOR]

Purpose: To determine the antioxidant activity of Crucus sativus extract and its effect on human skin using a non-invasive probe mexameter. Methods: The antioxidant activity of C. sativus extract was determined using DPPH method. Water in oil (w/o) topical cream of C. sativus extract (3%) was formulated and compared with the base (cream without extract). Both creams (formulation and base) were applied to the cheeks of 10 healthy human volunteers for a period of 8 weeks. Melanin and erythema values of skin were measured with a mexameter. Results: The antioxidant activity of the extract was 81%. Change in the levels of skin melanin and erythema was -24.04 ± 3.23 and -13.57 ± 2.28, respectively, indicating that unlike the base, the formulation containing Crocus sativus extract produced significant (p ≤ 0.05) depigmentation and anti erythemic effect on human skin. Conclusion: Application of the formulation containing 3% C. sativus extract to human skin may be useful in the management of melanoma. However, further studies are still required to ascertain this. [ABSTRACT FROM AUTHOR]

Signal transducer and activator of transcription (STAT) proteins represent novel therapeutic targets for the treatment of cancer. In particular, STAT-3 serves critical roles in several cellular processes, including the cell cycle, cell proliferation, cellular apoptosis and tumorigenesis. Persistent activation of STAT-3 has been reported in a variety of cancer types, and a poor prognosis of cancer may be associated with the phosphorylation level of STAT-3. Furthermore, elevated STAT-3 activity has been demonstrated in a variety of mammalian cancers, both in vitro and in vivo . This indicates that STAT-3 serves an important role in the progression of numerous cancer types. A significant obstacle in developing STAT-3 inhibitors is the demonstration of the antitumor efficacy in in vivo systems and the lack of animal models for human tumors. Therefore, it is crucial to determine whether available STAT-3 inhibitors are suitable for clinical trials. Moreover, further preclinical studies are necessary to focus on the impact of STAT-3 inhibitors on tumor cells. When considering STAT-3 hyper-activation in human cancer, selective targeting to these proteins holds promise for significant advancement in cancer treatment. In the present study, advances in our knowledge of the structure of STAT-3 protein and its regulatory mechanisms are summarized. Moreover, the STAT-3 signaling pathway and its critical role in malignancy are discussed, in addition to the development of STAT-3 inhibitors in various cancer types., (Copyright: © Gu et al.)

The aim of this research was to carry out a comparative study of lowering of uric acid by the use of dried powder of Colchicum luteum and allopathic drug (allopurinol) in rabbits, to determine whether herbal drugs can be used by patients instead of allopathic drugs. The herbal medicine, dried corm powder of Colchicum luteum 2.5 mg/kg/day and dried powder of allopurinol 2 mg/kg/day an allopathic medicine, was used in the study. The results of these medicines were observed in animal model, using 12 adult rabbits, which were divided into three groups A, B and C, respectively, where group C was taken as control. The SPSS version 17 was used for statistical analysis and analysis of variance (ANOVA) was used for comparing the data in different groups and the level of significance was 5%. It was resulted that dried corm of Colchicum luteum significantly reduced the uric acid in adult rabbits as reduced by allopathic medicine--allopurinol. In the light of present research we concluded that the herbal medicines can be used in lieu of allopathic drugs. Thus, the risk of side effects that are associated with the prolonged use of allopathic drugs can be minimized.