Synovial fold of the posterior shoulder joint capsule

Purpose  The purpose of the study is to describe, based on shoulder MRI and MR arthrography with arthroscopic correlation, a posterior joint capsule fold. Materials and methods  A retrospective review of 410 shoulder MRIs and direct MR arthrograms with arthroscopic correlation in positive cases (when available) was obtained with IRB approval and HIPPA compliance. The study was performed by three musculoskeletal radiologists. The criteria utilized to establish the diagnosis of posterior synovial fold included: (1) axial T1-weighted (T1W) on MR arthrography or axial T2* GRE-weighted on MRI demonstrating rounded thickening of the posterior shoulder joint capsule with a thickness at least 2 mm in diameter. (2) The posterior synovial fold extends in an oblique craniocaudal direction from the posterior–inferior joint capsule adjacent to the posterior–inferior glenoid labrum (7 o'clock) and continues superiorly away from the glenoid labrum to the posterior–superior joint capsule (11 o'clock). Results  Although uncommon, the posterior synovial fold was present in 2% (8/410) of studies reviewed and found predominantly in women (75%, 6/8). Four patients had arthroscopic confirmation of the posterior synovial fold. A higher percentage of posterior synovial folds were observed on shoulder MR arthrography (2.7%, 4/150) than on shoulder MRI (1.5%, 4/260). Conclusion  Although rare, the posterior synovial fold can be recognized and should not be confused with a posterior labral tear. Further investigation is needed to assess its histologic properties and its clinical significance.     

Measurement of resistance of amalgam mixes to condensation

A method was designed to evaluate the resistance of amalgam mixes to condensation forces. For the purpose of classification with respect to the plasticity of amalgam, the optimum test condition was to apply 40 or 50 lb of static load at 30 sec after trituration.     

Effects of brackets and ties on stiffness of an arch wire

Beam theory was used to evaluate the stiffness of a simulated orthodontic model as affected by the type of bracket, interbracket distance, type of ligature tie, and size of segment. For a given deflection, the model generated greater force (increased stiffness) as the beam constant (N) increased. N increased as interbracket distance increased. Metal ties were as rigid or more rigid than o-rings. Four bracket segments were more rigid than two-bracket segments when tied with o-rings but not metal ligatures. Values of N of Lewis and narrow twin brackets with metal ties were similar and greater than the N of wide twin and medium single brackets. Wide twin brackets were more rigid than others with o-rings.     

Brain targeted nanoparticulate drug delivery system of rasagiline via intranasal route

The aim of the present study was to prepare and evaluate a rasagiline-loaded chitosan glutamate nanoparticles (RAS-CG-NPs) by ionic gelation of CG with tripolyphosphate anions (TPP). RAS-loaded CG-NPs were characterized for particle size, size distribution, encapsulation efficiency and in vitro drug release. The mean particles size, polydispersity index (PDI) and encapsulation efficiency was found to be 151.1?±?10.31, 0.380?±?0.01 and 96.43?±?4.23, respectively. Biodistribution of RAS formulations in the brain and blood of mice following intranasal (i.n.) and intravenous (i.v.) administration was performed using HPLC analytical method. The drug concentrations in brain following the i.n. of CG-NPs were found to be significantly higher at all the time points compared to both drug (i.n.) and drug CG-NPs (i.v.). The Cmax (999.25?ng/ml) and AUC (2086.60?ng?h/ml) of formulation CG-NPs (i.n) were found to be significantly higher than CG-NPs (i.v.) and RAS solution (i.n.). The direct transport percentage (DTP%) values of RAS-loaded CG-NPs (i.n.) as compared to drug solution (i.n.) increased from 66.27?±?1.8 to 69.27?±?2.1%. The results showed significant enhancement of bioavailability in brain, after administration of the RAS-loaded CG-NPs which could be a substantial achievement of direct nose to brain targeting in Parkinson's disease therapy.     

The application of anethole,menthone, and eugenol in transdermal penetration of valsartan: Enhancement and mechanistic investigation

Context: The main barrier for transdermal delivery is the obstacle property of the stratum corneum. Many types of chemical penetration enhancers have been used to breach the skin barrier; among the penetration enhancers, terpenes are found as the most highly advanced, safe, and proven category.

Objective: In the present investigation, the terpenes anethole, menthone, and eugenol were used to enhance the permeation of valsartan through rat skin in vitro and their enhancement mechanism was investigated.

Materials and methods: Skin permeation studies of valsartan across rat skin in the absence and the presence of terpenes at 1% w/v, 3% w/v, and 5% w/v in vehicle were carried out using the transdermal diffusion cell sampling system across rat skin and samples were withdrawn from the receptor compartment at 1, 2, 3, 4, 6, 8, 10, 12, and 24?h and analysed for drug content by the HPLC method. The mechanism of skin permeation enhancement of valsartan by terpenes treatment was evaluated by Fourier transform infrared spectroscopy (FTIR) analysis and differential scanning calorimetry (DSC).

Results: All the investigated terpenes provided a significant (p?<?0.01) enhancement in the valsartan flux at a concentration of 1%, and less so at 3% and 5%. The effectiveness of terpenes at 1% concentration was in the following order: anethole?>?menthone?>?eugenol with 4.4-, 4.0-, and 3.0-fold enhancement ratio over control, respectively. DSC study showed that the treatment of stratum corneum with anethole shifted endotherm down to lower melting point while FTIR studies revealed that anethole produced maximum decrease in peak height and area than other two terpenes.

Conclusion: The investigated terpenes can be successfully used as potential enhancers for the enhancement of skin permeation of lipophilic drug.     

Mechanical properties and soldering of some cobalt base metal alloys

The mechanical properties of 5 cobalt base alloys for porcelain fused to metal and the strength of their solder joints have been determined. The variation in the composition of these alloys is reflected in their mechanical properties. The ranges of the mechanical properties of the materials tested were: (1) ultimate tensile strength — from 647 to 889.5 MPa; (2) yield strength — from 446.4 to 641.4 MPa; (3) modulus of elasticity — from 168.9 to 252.8×10³ MPa; (4) elongation — from 2 to 10%; and (5) hardness — from 350 to 440 VHN. Heat treatment did not have any significant effect on any of the mechanical properties except elongation which showed some variation. In general, stronger joints were made by soldering with a torch than by oven soldering. Also, presoldered joints were stronger than postsoldered ones. So, presoldering with a torch produced the strongest joints.     

Particulate and vesicular drug carriers in the management of tuberculosis

Although oral drug therapy for tuberculosis exists and is widely followed, its major drawbacks are lack of patient compliance and development of adverse effects like hepatotoxicity on long term use. Absence of new therapeutic agents and the above mentioned demerits have led to search for alternative methods for delivery of antitubercular agents. Colloidal drug carriers, a popularly utilized delivery system has been deeply explored for the cause. The article discusses the advances in the management of tuberculosis by the use of particulate and vesicular drug carriers by parenteral, inhalational and oral routes. Use of this delivery strategy has led to massive reduction in the dosage resulting in toxicity alleviation. As a number of studies have already been undertaken in experimental models, it will be a promising tool in the prevention of relapse and successful treatment of tuberculosis in patients.