Craniosynostosis in transgenic mice overexpressing Nell-1

Previously, we reported NELL-1 as a novel molecule overexpressed during premature cranial suture closure in patients with craniosynostosis (CS), one of the most common congenital craniofacial deformities. Here we describe the creation and analysis of transgenic mice overexpressing Nell-1. Nell-1 transgenic animals exhibited CS-like phenotypes that ranged from simple to compound synostoses. Histologically, the osteogenic fronts of abnormally closing/closed sutures in these animals revealed calvarial overgrowth and overlap along with increased osteoblast differentiation and reduced cell proliferation. Furthermore, anomalies were restricted to calvarial bone, despite generalized, non-tissue-specific overexpression of Nell-1. In vitro, Nell-1 overexpression accelerated calvarial osteoblast differentiation and mineralization under normal culture conditions. Moreover, Nell-1 overexpression in osteoblasts was sufficient to promote alkaline phosphatase expression and micronodule formation. Conversely, downregulation of Nell-1 inhibited osteoblast differentiation in vitro. In summary, Nell-1 overexpression induced calvarial overgrowth resulting in premature suture closure in a rodent model. Nell-1, therefore, has a novel role in CS development, perhaps as part of a complex chain of events resulting in premature suture closure. On a cellular level, Nell-1 expression may modulate and be both sufficient and required for osteoblast differentiation.

Nodular fat necrosis in the feline and canine abdomen

The radiographic appearance of nodular fat necrosis is described in ten cats and one dog. The most common radiographic sign was the presence of a focal mineralized circular to oval soft tissue mass in the abdominal fat as present in 9 cats. These masses had a distinct eggshell-like rim encapsulating the lesion. In one cat and one dog multiple masses were present, without radiographic signs of mineralization. Abdominal ultrasound was performed in three cats and one dog, findings included the presence of hyperechoic masses with associated acoustic shadowing, some with a hypoechoic centre. Almost all animals were old and obese. In three cats and one dog, changes were confirmed with biopsy or post mortem examination. Lesions having the appearance of those in this paper are most likely incidental findings and should not be confused with abdominal masses of neoplastic origin. Ultrasound can be helpful in identifying such lesions.

Refinement of a technique for thermocholecystectomy in an animal model

RATIONALE AND OBJECTIVES

A modification of a thermal ablation system was tested for improved cystic duct occlusion and gallbladder mucosa ablation in an animal model.

METHODS

Fourteen domestic swine were included in group 1 with thermal treatment of the cystic duct to 75 degrees C for 15 minutes, followed by heating of the gallbladder lumen with a catheter/heating device to 54 degrees C for 30 minutes. One swine served as a control (group 2). A ligature was placed around the cystic duct without thermal treatment of the cystic duct and with the catheter/heating device placed into the gallbladder for 30 minutes without thermal treatment. All animals were killed after 3 weeks with histologic examination of the gallbladder, cystic duct, and surrounding organs.

RESULTS

In group 1, technical failure due to catheter clogging occurred in the first three animals, which were killed immediately. Eleven animals were treated with a redesigned catheter system. Three weeks after treatment, 10 of the 11 animals had complete cystic duct occlusion and complete obliteration of the cystic duct mucosa. One of the 11 animals experienced partial cystic duct ablation. Nine of the 11 treated animals experienced complete mucosal ablation of the gallbladder. Five of the 11 animals had no residual lumen, whereas 6 of the 11 had a luminal volume that averaged 4 mL compared to 35 mL before treatment. In group 2, the control subject had a gallbladder volume of 50 mL and normal gallbladder and cystic duct mucosa.

CONCLUSIONS

This study demonstrates improvement in both cystic duct occlusion and gallbladder mucosa ablation with standardization of the technique for thermocholecystectomy in an animal model. However, a better system is required to promote complete obliteration of the gallbladder lumen.

Evaluation of a method of ureteroneocystostomy in cats

Renal transplantation is a successful treatment for terminal renal failure in cats. Ureteral obstruction at the bladder wall or stoma has been a technical complication encountered in approximately 50% of clinical transplants. The small (0.4 mm) diameter of the feline ureter makes standard techniques described for ureteroneocystostomy unsatisfactory for cats. In this study, we used microsurgical techniques to oppose ureteral mucosa to intact bladder mucosa in an attempt to form a stricture-free stoma. In each of 5 anatomically normal cats, 1 ureter was microsurgically implanted in the bladder. Ultrasonographic examination of the kidneys, ureters, and bladder was performed twice weekly for 8 weeks. Excretory urography was performed at postoperative weeks 1, 2, 4, 8, and 12. Biopsy specimens were taken from the kidney on the surgically treated side 4 weeks after surgery. At 12 weeks, the kidney, ureter, and ureterovesical junction from the treated side were removed and submitted for histologic evaluation. At 1 week, all cats had enlargement of the kidney, renal pelvis, and ureteral lumen on the treated side. This enlargement gradually decreased, and by week 8, there was no difference in comparison with the control side. Ureteroneocystostomy that requires tunneling of the ureter through the bladder wall may result in hydroureter and hydronephrosis, which may resolve. Recognition of these changes may prevent unwarranted surgical intervention in cases of suspected obstruction. The technique described in this study has been used in 15 cats receiving renal allografts. None required surgical correction of ureteral obstruction.

Treatment of a demented patients anger with cognitive-behavioral strategies

The effect of cognitive-behavioral strategies in treatment of a demented patient's anger was studied. Ratings from a 10-point Likert-type scale were used to quantify the patient's outbursts of anger during a 2-wk. baseline period and a 6-wk. treatment. At a 3-mo. follow-up the number of outbursts of anger was noted by nursing staff on the patient's chart. The combination of interventions seemed effective in controlling outbursts.