Standard metabolic rate at the surface and during trained submersions in adult California sea lions (Zalophus californianus).

The metabolic rate (MR) of four adult California sea lions (Zalophus californianus), two males and two females, was quantified during trained submersion and stationing behavior in laboratory tanks. MR was measured, at rest and for single submersions of increasing duration (1-7 min), by measuring oxygen consumption using open-circuit, indirect calorimetry. Standard MR was measured under conditions defined for basal MR and was found to be 1.9 to 3 times that predicted for terrestrial animals of similar size. Submersion MRs were calculated from the post-submersion oxygen debt and declined to as little as 47 % of standard MR on the longest submersions. This hypometabolic response was proportional to the duration of submersion and was greatest for the maximum duration submersions. Short submersions produced MRs equivalent to measured standard MR. These data suggest that although California sea lions maintain an elevated metabolism under standard conditions, they are capable of reducing their metabolism in response to the needs of diving. Such metabolic flexibility enables sea lions to moderate their oxygen use during diving and to extend their aerobic diving capability.

Results of arthroscopic versus open Bankart suture repair.

The purpose of this study was to compare patients with anterior shoulder instability who were treated with an open Bankart procedure with those treated with an arthroscopic procedure. During a 3-year period, 43 patients (44 shoulders) were surgically treated. Thirty-four patients were available for followup. Eighteen shoulders had open Bankart procedure, and 16 shoulders were treated arthroscopically. Capsular laxity can be better assessed with the open procedure. A Bankart lesion was found in all the patients in both series. Average followup for Group 1 was 34 months, and for Group 2, it was 23 months. Group 1 had 83% good to excellent results with no recurrent dislocation or reoperation. Group 2 had 50% good to excellent results, and 50% fair to poor results with 3 recurrent dislocations and 4 recurrent subluxations that required second operation. The average loss of external rotation in Group 1 was not significantly greater than that in Group 2. Sixteen patients in Group 1 and 8 patients in Group 2 were able to return to their primary work or sport. Results of arthroscopic Bankart repair do not equal those of the open Bankart procedure for the rate of recurrence and postoperative range of motion. The followup reported is short, and more dislocations can be anticipated with longer followup.

Molecular cloning and functional expression of a mu-opioid receptor from rat brain.

Opioid drugs act on specific receptors to modulate a wide range of physiological functions. There are at least three types of opioid receptors, mu, delta, and kappa. Using a cDNA probe for a mouse delta-opioid receptor in low stringency hybridization, a clone has been isolated from a rat brain cDNA library. This clone contains an open reading frame of 1194 base pairs, with a deduced polypeptide of 398 amino acid residues. The predicted protein exhibits the structural features of guanine nucleotide-binding protein-coupled receptors and displays a high degree of sequence homology with the mouse delta-opioid receptor. When transfected into COS-7 cells, the cDNA conferred a binding site with subnanomolar affinity for [3H]diprenorphine, a high affinity ligand for all three types of opioid receptors. This site also displayed nanomolar affinity for [D-Ala2,N-Me-Phe4,Gly-ol5]-enkephalin (DAGO), a mu-selective agonist, whereas its affinities for the delta-selective agonist [D-Pen2,5]-enkephalin and the kappa-selective agonist U-50488 were in the micromolar range. Several mu-selective antagonists, including naloxonazine, beta-funaltrexamine, and cyprodime, were capable of displacing [3H]diprenorphine binding with nanomolar potency. The pharmacological profile of this binding site thus suggests that it is a mu-type opioid receptor, which we designated MOR-1. In COS-7 cells expressing MOR-1 and stimulated with forskolin, treatment with DAGO decreased the steady state levels of cAMP; this inhibitory effect of DAGO was blocked by naloxonazine. These results suggest that this mu-opioid receptor is functionally coupled to the inhibition of adenylyl cyclase.

Posterior shoulder instability. Surgical versus conservative results with evaluation of glenoid version.

We conducted a retrospective study on 50 patients with recurrent posterior shoulder instability. Twenty-five patients were treated conservatively with a specific rehabilitation program strengthening the rotator cuff. The other 25 patients, who did not improve with rehabilitation, underwent surgical reconstruction, the majority of these being soft tissue repairs. Recurrence in the surgically treated group averaged 72% while that in the conservatively treated group was 96%. However, 50% of those patients treated surgically and 68% of those treated conservatively felt their symptoms were improved. In view of the high recurrence rate with soft tissue reconstruction, computed tomography scans were obtained to evaluate glenoid version. Those patients with posterior shoulder instability were found to have increased glenoid retroversion when compared to an uninjured population (P less than 0.05). Our conclusions based on this study were that 1) specific therapy in the form of rotator cuff strengthening should be the initial form of treatment in patients with posterior shoulder instability, 2) soft tissue surgery has a high rate of recurrence, 3) the return to sports is variable, 4) there appears to be an increased incidence of glenoid retroversion in this patient population, and 5) the incidence of posttraumatic arthritis is low.

Shoulder arthroscopy: its role in evaluating shoulder disorders in the athlete.

We retrospectively reviewed 100 initial shoulder arthroscopies from a general sports medicine orthopaedic practice to determine if arthroscopy is helpful diagnostically and to see if specific lesions correlate well with specific diagnoses. Seventy-two percent of the patients in the review had glenoid labral tears. Ninety-two percent of patients who had a diagnosis of either recurrent anterior dislocation or recurrent anterior subluxation demonstrated a tear of the anterior inferior margin of the glenoid labrum. Sixty-eight percent of patients with a diagnosis of impingement demonstrated tears at the superior margin of the labrum. There was a significant difference between throwing and nonthrowing athletes. Partial rotator cuff tears were noted in 18 patients, the majority occurring in throwing athletes. Other abnormalities, such as degenerative joint changes and biceps tendon lesions, were also noted at the time of arthroscopy. A large number of glenoid labral tears found at the time of arthroscopy appeared to be associated with conditions other than instability, which may or may not affect the throwing athlete. There also appeared to be a high correlation between tears in the anterior inferior glenoid labrum and anterior instability. Arthroscopy enabled us to identify other significant information about the status of the biceps tendon or the undersurface of the rotator cuff. These are areas in which problems might otherwise have been missed. Degenerative changes of the articular surface, not apparent on plain radiographs, may also be better evaluated arthroscopically.

Multicentric reticulohistiocytosis in a patient with malignant melanoma: a response to cyclophosphamide and a unique cutaneous feature.

We describe a patient with multicentric reticulohistiocytosis and a history of malignant melanoma. His widely disseminated disease did not affect the site of surgical removal of the malignant melanoma nor the donor site of a skin graft. The multicentric reticulohistiocytosis progressed while the patient was taking nonsteroidal antiinflammatory agents, but showed significant response during a 10-month course of cyclophosphamide. While he was taking the cyclophosphamide, however, his melanoma recurred, and the patient subsequently died.

Complicated elbow fractures in athletes.

The elbow is a key link in the function of the upper extremity and therefore, is subject to various stresses and strains. These stresses may be in the form of a single macrotrauma or repetitive microtrauma with each having its effect on the architecture of the elbow. In dealing with athletes with elbow disorders, one is faced with the challenge of maintaining mobility while achieving maximal stability. Therefore, what has been proposed are treatment formulas for some of the more common elbow fractures that affect the athletic population, which the author has found to be quite useful in achieving these goals.

Transverse myelitis and optic neuritis in systemic lupus erythematosus: a case report with magnetic resonance imaging findings.

We describe a patient with systemic lupus erythematosus who developed transverse myelitis and optic neuritis. Magnetic resonance imaging showed the presence of an abnormal signal in a normal-sized spinal cord which corresponded to the patient's neurologic deficit. No abnormality was recognized in either optic nerve. Magnetic resonance may prove to be a useful imaging modality for the diagnosis of a transverse myelopathy in systemic lupus erythematosus.

Tubuloreticular inclusions in systemic lupus pneumonitis. Report of a case and review of the literature.

Tubuloreticular inclusions have been described with sufficient frequency in certain tissues of patients with systemic lupus erythematosus (SLE) to make the finding of such inclusions helpful in making a diagnosis of this disorder. The finding of such inclusions in lung biopsy specimens, however, has been distinctly rare. We report herein the ultrastructural findings in the case of a young woman with active systemic LE showing tubuloreticular inclusions within lung and kidney biopsy specimens.