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Introduction: Periprosthetic fractures and dislocation in the early post-operative period can be disastrous both for the surgeon and the patient. However, undisplaced periprosthetic fractures presenting with dislocation is uncommon. We describe successful management of two cases (one bilateral dislocation and one unilateral dislocation) of undisplaced iatrogenic fractures in total hip arthroplasty (THA) presenting as early dislocation. Case Report: Case 1 was a 45-year-old female with osteoarthritis of hip secondary to developmental dysplasia of the hip with bilateral early nontraumatic dislocation with bilateral identical periprosthetic fracture. It was managed by revision to long stem and encirclage wiring. Case 2 presented with early dislocation in the 2nd week post THA. We found an intertrochanteric fracture intra-operatively with unstable implant. Acetabular component and femoral component revision were done with reconstruction of the greater trochanter. Discussion: These fractures could be occult iatrogenic fractures characteristic of taper wedge stems which presented as early nontraumatic dislocation in the post-operative period. The prosthesis subsidence, loss of muscle tension and change of version might be the factors leading to dislocation. Conclusion: Unrecognized incomplete intraoperative fracture can occur with tapered wedge uncemented stems which can present as a dislocation in the immediate post-operative period. This will require early revision of the femoral component.

A hexamer of the bacteriophage T4 tail terminator protein, gp15, attaches to the top of the phage tail stabilizing the contractile sheath and forming the interface for binding of the independently assembled head. Here we report the crystal structure of the gp15 hexamer, describe its interactions in T4 virions that have either an extended tail or a contracted tail, and discuss its structural relationship to other phage proteins. The neck of T4 virions is decorated by the “collar” and “whiskers”, made of fibritin molecules. Fibritin acts as a chaperone helping to attach the long tail fibers to the virus during the assembly process. The collar and whiskers are environment-sensing devices, regulating the retraction of the long tail fibers under unfavorable conditions, thus preventing infection. Cryo-electron microscopy analysis suggests that twelve fibritin molecules attach to the phage neck with six molecules forming the collar and six molecules forming the whiskers.

This article, which is the first in a planned series intended to address chemistry, manufacturing, and control (CMC) aspects of therapeutic oligonucleotides, examines the topic of specifications for active pharmaceutical ingredients (APIs). The authors attempt to present basic scientific considerations for the broadest range of oligonucleotide APIs. Tests and analytical methods suitable for the control of single- and double-stranded oligonucleotide APIs and conjugated oligonucleotide APIs are discussed.

The Effect of Gonadotropins on the steroidogenic Potential and Spermatogenesis in the Testis of the Catfish, Clarias batrachus (Linn)

It is important to remember that while a new class of therapeutic agents like oligonucleotides may introduce novel concerns, the basic regulatory issues regarding the chemistry, manufacturing, and controls of drug substances and drug products must be addressed. This article focuses on information that should be included in an Investigational New Drug Application (IND), a request to use an investigational drug in clinical studies. The regulatory challenge presented with oligonucleotide therapeutics is to prove the identity of the oligonucleotide, and demonstrate its quality, purity, and strength/potency using both those characteristics that are the same as all other drugs, as well as those that are unique. Most of the discussion will concern issues that are unique to oligonucleotides, or those topics that deserve more detailed attention than would be needed for more typical small molecule drugs. Regulatory issues will need to be evaluated so that safety concerns are addressed while not imposing undue burden on the sponsors of investigational drugs.