Preparation of nasal temperature-sensitive in situ gel of Radix Bupleuri and evaluation of the febrile response mechanism.

OBJECTIVE: This study developed a nasal temperature-sensitive in situ gel system for Radix Bupleuri. METHOD: Using 20% Poloxamer 407 as the gel base and 6% PEG 4000 adjusting the gelation temperature. RESULTS: The system is liquid at 4 degrees C. It can change its phase to gel above 30 degrees C, which is close to the temperature in nasal cavity. The antipyretic effect produced by Radix Bupleuri in situ gel formulation was investigated in fevered rabbits. The results show that it can prolong the effective time to 24 hours compared with 4-6 hours in Radix Bupleuri intranasal solution. The antipyretic response mechanism was researched by evaluating the relationship between body temperature and concentrations of cyclic adenosine monophosphate in cerebrospinal fluid. The results showed that the two parameters were positively correlated (r = 0.9435, P < 0.05). Six hours later after given in situ gel, the concentrations of cAMP were significantly lower than those in the solution group. It confirmed that temperature-sensitive Radix Bupleuri in situ gel applied in the nasal sprays had a longer residence and release time. CONCLUSION: Radix Bupleuri nasal temperature-sensitive in situ gel has a higher medical effect and a longer effective time. Compared to the traditional nasal spray, it is more applicable for the treatment of fever.

In situ gel based on gellan gum as new carrier for nasal administration of mometasone furoate.

The main purpose of this study was to prepare a novel in situ gel system for nasal delivery of MF and study its efficacy on allergic rhinitis model. An ion-activated in situ gel was developed and characterized with gellan gum as a carrier. The system was stable kept at 40+/-2 degrees C for 6 months, and the micrographic results showed that in situ gel was safety without mucosa irritation when given at 20 microg once daily for 1 month to rats with allergic rhinitis. MF in gellan gum produced obviously effect on allergic rhinitis at the doses of 20 microg/body following intranasal administration, and the efficacy was significantly superior to that of the common suspension (P<0.01). The in situ gel system is a promising approach for the intranasal delivery of MF for the therapeutic effects improvement.

A novel arthroscopic procedure for fixation of avulsion fracture of tibial attachment of anterior cruciate ligament guided by meniscal stitching needle.

OBJECTIVE: To introduce a novel technique in which meniscal stitching needle is used as a puller to induct steel wire to secure the tibial eminence avulsion under arthroscopic visualization, and evaluate the clinical results. METHODS: From 1999 to 2005, fifteen cases of tibial eminence avulsion were treated with this new technique. Lysholm scoring scale system was used to assess knee function before and after surgery. Regular plain anteroposterior and lateral X-ray films were undertaken to detect the bony healing of avulsed fragment. RESULTS: The operating time could be controlled within 30 minutes. No complications such as intraarticular infection, iatrogenic injury, fibroarthritis or nonunion of fracture occurred in this group. X-ray film revealed that bony healing in all 15 cases was achieved from 6 weeks to 12 weeks postoperatively. Lysholm score was improved from 19.1+/-15.2 (ranging from 10 to 56) preoperatively to 97.5+/-3.7 (ranging from 91 to 100) postoperatively on average in 12-54 months follow up (mean 23 months). The statistically significant difference was shown in Student's t test (t equal to 18.483, P equal to 3.100 x 10(-11), P < 0.01). Wire breakage was found in two patients whose wires were removed 8 months and 14 months after initial operation, respectively. CONCLUSION: This technique has many advantages, such as simplicity, wide indications from type II to type IV fractures, minimal invasion, short operating time and predictable satisfactory results.

A novel nasal delivery system of a Chinese traditional medicine, Radix Bupleuri, based on the concept of ion-activated in situ gel.

The purpose of this study was to develop a nasal in situ gel system for Radix Bupleuri employing gellan gum as a polymer. Radix Bupleuri in situ gel containing 0.2 mL essential oil extracted from 450 g Radix Bupleuri, proper solubilizing agents and gellan gum (0.5% w/v) was prepared and characterized. The antipyretic effect produced by in situ gel formulation was investigated in fevered rabbits and compared to an intranasal solution. The resulting in situ gel was a clear and light-yellow liquid, with viscosity of 346 mPa x s and caproic acid content of 1.31 +/- 0.01 mg/mL. Intranasal administration of this preparation to fevered rabbits decreased body temperature markedly (1.1 degree C at the doses of oil from 1.5 g Bupleuri/body) and the effect could last for 20-30 h. The results suggest that Radix Bupleuri in situ gel can be greater effective than the solution in the treatment of fever.

Preparation of ion-activated in situ gel systems of scopolamine hydrobromide and evaluation of its antimotion sickness efficacy.

AIM: To develop a novel, in situ gel system for nasal delivery of scopolamine hydrobromide (SCOP) and study its efficacy on motion sickness. METHODS: SCOP in situ gels at 0.2%, 0.5%, and 1.0% gellan gum concentration (w/v) were prepared, respectively, and characterized in terms of viscosity, in vitro release, and nasal ciliotoxicity. Single photon emission computing tomography technique was used to evaluate the nasal residence time of gel containing (99m)Tc tracer. The antimotion sickness efficacy produced by the in situ gel formulation was investigated in rats and compared with those achieved after subcutaneous and oral administration. RESULTS: The viscosity of the gellan gum formulations either in solution or in gel increased with increasing concentrations of gellan gum. Its release in vitro was moderate in artificial nasal fluid. The micrographic results showed that in situ gels were safe, without nasal ciliotoxicity. In comparison with phosphate buffer saline, a prolonged radioactivity of (99m)Tc in the rabbit nasal cavity was observed after administration of the gellan gum formulation. Intranasal SCOP in situ gel at a dose of 100 microg/kg decreased symptoms of motion sickness significantly in comparison with subcutaneous and oral administration (P<0.01). CONCLUSION: SCOP nasal in situ gel is a safe and promising therapeutic alternative to existing medications for motion sickness.