Complex fractures of the clivus: diagnosis with CT and clinical outcome in 11 patients

During a 20-month period, fractures of the clivus occurring after craniocerebral trauma were diagnosed with computed tomography (CT) in 11 patients. Five patients had longitudinally oriented fractures; these were fatal in four patients due to either vertebral-basilar artery occlusion, brain stem trauma, or both. Six other patients had transversely oriented fractures that extended through the carotid canal and petrous temporal bone. While less frequently contributing directly to mortality, transverse fractures were also associated with cerebrospinal fluid leaks (two patients) and a cavernous sinus-carotid fistula (one patient). They were not as frequently associated with Horner syndrome or cranial nerve deficits as suggested in the current literature. This retrospective evaluation reveals two distinct injury patterns that demonstrate a difference in related morbidity and mortality.     

Centrally acting mechanisms for the treatment of male sexual dysfunction

The development of pharmacologic therapy for erectile dysfunction (ED) has been possible because of incremental growth in our understanding of the physiology of normal erections and the complex pathophysiology of ED. Although the oral phosphodiesterase type 5 (PDE5) inhibitors have provided safe, effective treatment of ED for some men, a large proportion of men who have ED do not respond to PDE5 inhibitors or become less responsive or less satisfied as the duration of therapy increases. Also, men who are receiving organic nitrates and nitrates, such as amyl nitrate, cannot take PDE5 inhibitors because of nitrate interactions. The current options for treatment beyond PDE5 inhibitors are invasive, unappealing to some patients, and sometimes ineffective. The search for other options by which ED can be treated has branched out and now encompasses centrally acting mechanisms that control erectile function. Drugs available in Europe include apomorphine. This article focuses on the mechanism of centrally acting agents and reviews clinical data on potential new centrally acting drugs for men who have ED.     

Current role of palliative interventions in advanced pancreatic cancer

Pancreatic adenocarcinoma is the third leading cause of cancer death in the United States. Unfortunately, at diagnosis, most patients are not candidates for curative resection. Surgical palliation, a procedure performed with the intention of relieving symptoms or improving quality of life, comes to the forefront of management. This article reviews the palliative management of unresectable pancreatic cancer, including obstructive jaundice, duodenal obstruction and pain control with celiac plexus block. Although surgical bypasses for both biliary and duodenal obstructions usually achieve good technical success, they result in considerable perioperative morbidity and mortality, even when performed laparoscopically. The effectiveness of selfexpanding metal stents for biliary drainage is excellent with low morbidity. Surgical gastrojejunostomy for duodenal obstruction appears to be best for patients with a life expectancy of greater than 2 mo while endoscopic stenting has been shown to be feasible with good symptom relief in those with a shorter life expectancy. Regardless of the palliative procedure performed, all physicians involved must be adequately trained in end of life management to ensure the best possible care for patients.     

Lumbar Pseudomeningocele Causing Hydronephrosis

Background/Objective: Pseudomeningocele is most commonly the result of a rent in the meninges during spine surgery. Noniatrogenic causes exist but are rare. Pseudomeningoceles may heal spontaneously, but they may also slowly enlarge. They rarely present as a mass within the abdomen. The objective of this study was to present the first case report of hydronephrosis secondary to lumbar pseudomeningocele.

Design: Single case report and literature review.

Methods: Single case report.

Results: This man had undergone extensive lumbar spine surgery for pain and spondylolisthesis. He subsequently developed a pseudomeningocele that caused hydronephrosis of the left kidney. He was treated with surgical intervention and had resolution of his hydronephrosis and his flank and groin pain. He also had improvement of his back pain.

Conclusions: This report shows an unusual cause of hydronephrosis—a pseudomeningocele presenting as an abdominal mass that compressed the ureter.     

Traumatic epidural hematoma of the cervical spine: diagnosis with magnetic resonance imaging. Case report

A traumatic epidural hematoma of the cervical spine is reported in a 13-year-old girl. The patient recovered spontaneously over several days without surgical intervention. The diagnosis was made on magnetic resonance (MR) imaging, which also demonstrated subsequent resolution of the hematoma. The etiological factors of spinal epidural hematomas are reviewed and the utility of MR imaging in differentiating other causes of acute spinal cord injury is emphasized.     

Physical and functional interactions between Stat5 and the tyrosine- phosphorylated receptors for erythropoietin and interleukin-3

Erythropoietin (Epo) and interleukin-3 (IL-3) stimulate activation of the Jak2 tyrosine kinase and induce tyrosine phosphorylation and activation of Stat5. In the present study, we have shown that Epo or IL- 3 stimulation induces binding of Stat5 to the tyrosine-phosphorylated Epo receptor (EpoR) or IL-3 receptor beta subunit (betaIL3), respectively, in IL-3-dependent 32D cells expressing the EpoR. The binding of Stat5 to these cytokine receptors was shown to be rapid and transient, occurring within 1 minute of stimulation of cells and significantly decreasing after 5 minutes of cell treatment. In vivo binding experiments in COS cells showed that binding of Stat5 to the EpoR was mediated through the Stat5 Src homology 2 (SH2) domain. In vitro binding studies further showed that Stat5, but not other Stats examined, bound specifically to tyrosine-phosphorylated recombinant EpoR fusion proteins. In these in vivo and in vitro binding studies, Stat5 bound, albeit to a lesser degree, to truncated EpoR mutants in which all the intracellular tyrosines except Y-343 were removed. Furthermore, EpoR-derived synthetic phosphotyrosine peptides corresponding to Y-343, Y-401, Y-431, and Y-479 inhibited the in vitro binding of Stat5. When expressed in 32D cells, a mutant EpoR in which all the intracellular tyrosines were removed by carboxy-terminal truncation showed a significantly impaired ability to induce tyrosine phosphorylation of Stat5, particularly at low concentrations of Epo, but exhibited an increased sensitivity to Epo for growth signaling as compared with the wild-type EpoR. These results indicate that Stat5 specifically and transiently binds to the EpoR through the interaction between the Stat5 SH2 domain and specific phosphorylated tyrosines, including Y-343, in the EpoR cytoplasmic domain. It was implied that betaIL3 may also have similar Stat5 docking sites. The Stat5 docking sites in the EpoR were shown to facilitate specific activation of Stat5, which, however, may not be required for the EpoR-mediated growth signaling.