Muscle Atrophy at Presentation of Cubital Tunnel Syndrome: Demographics and Duration of Symptoms.

Background: The purpose of this study is to describe the demographics and duration of symptoms of patients with cubital tunnel syndrome who present with muscle atrophy. Methods: We identified 146 patients who presented to the hand surgery clinic at a single institution over a 5-year period with an initial diagnosis of cubital tunnel syndrome based on history and physical examination. Medical records were retrospectively reviewed to determine if there was a difference in demographic data, physical examination findings, and duration of symptoms in patients who presented with muscle atrophy from those with sensory complaints alone. Results: A total of 17/146 (11.6%) of patients presented with muscle atrophy, all of which were men. In all, 17.2% of men presented with atrophy. Age by itself was not a predictor of presentation with atrophy; however, younger patients with atrophy presented with significantly shorter duration of symptoms. Patients under the age of 29 years presenting with muscle atrophy on average had symptoms for 2.4 months compared with 16.2 months of symptoms for those over 55 years of age. Conclusions: Men with cubital tunnel syndrome are more likely to present with muscle atrophy than women. Age is not necessarily a predictor of presentation with atrophy. There is a subset population of younger patients who presents with extremely short duration of symptoms that rapidly develops muscle atrophy.

Sedimentation velocity and potential in concentrated suspensions of charged porous spheres.

The body-force-driven migration in a homogeneous suspension of polyelectrolyte molecules or charged flocs in an electrolyte solution is analyzed. The model used for the particle is a porous sphere in which the density of the hydrodynamic frictional segments, and therefore also that of the fixed charges, is constant. The effects of particle interactions are taken into account by employing a unit cell model. The overlap of the electric double layers of adjacent particles is allowed and the relaxation effect in the double layer surrounding each particle is considered. The electrokinetic equations which govern the electrostatic potential profile, the ionic concentration (or electrochemical potential energy) distributions, and the fluid velocity field inside and outside the porous particle in a unit cell are linearized by assuming that the system is only slightly distorted from equilibrium. Using a regular perturbation method, these linearized equations are solved for a symmetrically charged electrolyte with the density of the fixed charges as the small perturbation parameter. An analytical expression for the settling velocity of the charged porous sphere is obtained from a balance among its gravitational, electrostatic, and hydrodynamic forces. A closed-form formula for the sedimentation potential in a suspension of identical charged porous spheres is also derived by using the requirement of zero net electric current. The dependence of the sedimentation velocity and potential of the suspension on the particle volume fraction and other properties of the particle-solution system is found to be quite complicated.

Diagnosis of an interstitial pregnancy with 4-dimensional volume contrast imaging.

OBJECTIVE: The purpose of this study was to investigate the use of a new ultrasound technique, termed 4-dimensional volume contrast imaging in coronal-plane to facilitate the early detection of interstitial pregnancy. STUDY DESIGN: A case of interstitial pregnancy was diagnosed accurately at 6 weeks of gestation with 4-dimensional transvaginal volume contrast imaging in coronal plane technology. A scan of the uterus revealed that the eccentric gestational sac was located in the right uterotubal junctional area, lying 1 cm outside the most upper lateral edge of the uterine cavity with thick endometrial echoes. RESULTS: After the appropriate counseling, the patient was treated with an ultrasonographically guided intracardiac injection of 2.5 mEq of potassium chloride followed by aspiration of the gestational sac. A transvaginal scan immediately after the procedure demonstrated a collapsed empty gestational sac. Three months after the conservative treatment, the serum beta-human chorionic gonadotropin level fell to 1.17 mIU/mL, and normal echotexture of the uterus was noted. CONCLUSION: Four-dimensional volume contrast imaging in coronal-plane technology provides scan planes that are not accessible by conventional 2-dimensional scanning, with enhanced tissue contrast resolution in region of interest. This new ultrasound technique has the potential to provide more accurate, inexpensive and less variable virtual reality image-guided interventional options through more realistic interaction with the virtualized in utero condition, particularly when 2-dimensional transvaginal scan fails to differentiate between interstitial, angular, and cornual pregnancies.

Effect of celecoxib on Ca2+ movement and cell proliferation in human osteoblasts.

In human osteoblasts, the effect of the widely prescribed cyclooxygenase-2 inhibitor celecoxib on intracellular Ca(2+) concentrations ([Ca(2+)](i)) and cell proliferation was explored by using fura-2 and the tetrazolium assay, respectively. Celecoxib at concentrations greater than 1microM caused a rapid rise in [Ca(2+)](i) in a concentration-dependent manner ( EC 50= 10 microM). Celecoxib-induced [Ca(2+)](i) rise was reduced by 90% by removal of extracellular Ca(2+), and by 30% by l-type Ca(2+) channel blockers. Celecoxib-induced Mn(2+)-associated quench of intracellular fura-2 fluorescence also suggests that celecoxib-induced extracellular Ca(2+) influx. In Ca(2+)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2+)-ATPase, caused a monophasic [Ca(2+)](i) rise, after which the increasing effect of celecoxib on [Ca(2+)](i) was greatly inhibited. Conversely, pretreatment with celecoxib to deplete intracellular Ca(2+) stores totally prevented thapsigargin from releasing more Ca(2+). U73122, an inhibitor of phoispholipase C, abolished histamine (an inositol 1,4,5-trisphosphate-dependent Ca(2+) mobilizer)-induced, but not celecoxib-induced, [Ca(2+)](i) rise. Pretreatment with phorbol 12-myristate 13-acetate and forskolin to activate protein kinase C and adenylate cyclase, respectively, partly inhibited celecoxib-induced [Ca(2+)](i) rise in Ca(2+)-containing medium. Separately, overnight treatment with 1-100microM celecoxib inhibited cell proliferation in a concentration-dependent manner. These findings suggest that in human osteoblasts, celecoxib increases [Ca(2+)](i) by stimulating extracellular Ca(2+) influx and also by causing intracellular Ca(2+) release from the endoplasmic reticulum via a phospholiase C-independent manner. Celecoxib may be cytotoxic at higher concentrations.