Cloning of the proto-oncogene c-src from rat testis.

The cellular homolog of the oncogene v-src, the proto-oncogene c-src, was cloned from rat testis using a high stringency polymerase chain reaction. Rat c-src cDNA shared identity with chicken and mouse, and Rous sarcoma virus c-src and v-src, respectively. Rat c-Src protein was 98% homologous to both human and mouse c-Src. Interestingly, rat Src contained one extra amino acid compared to the mouse protein. As expected, the rat testis Src lacked the six extra residues common to the neuronal Src identified in human and mouse. Reporting of the cDNA sequence for non-neuronal, rat c-src should facilitate experimentation into cell growth and transformation using rat tissues as models of human disease.

Cavernous angiomas of the cauda equina: case report and review of the literature.

BACKGROUND: Cavernous hemangiomas of the spine and spinal cord are relatively uncommon lesions that are being discovered more frequently because of the increased use of magnetic resonance imaging (MRI). We present a rare case of a symptomatic cavernous hemangioma of the cauda equina. CASE DESCRIPTION: A 49-year-old woman presented to our institution with the chief complaint of low back pain of acute onset. On physical examination the patient was found to be tender to percussion over the lumbar spine, had tenderness over the sciatic nerve, loss of pinprick sensation over the right lateral foot and loss of the Achilles' reflex on the right. In addition, she was found to have a large postvoid urinary bladder residual volume. MRI revealed a 20 mm x 11 mm nonenhancing, heterogenous mass obliterating the spinal canal at the L4 level. At operation, this lesion was found to be adherent to the nerve roots and was completely resected. Pathology revealed this lesion to be a cavernous angioma of the cauda equina. A review of the pertinent literature is presented. CONCLUSIONS: Cavernous hemangiomas of the cauda equina are extremely rare lesions that may present as low back pain, neurologic deficit, or as subarachnoid hemorrhage. They can be successfully treated with surgical excision.

Outcome after urgent surgery for grade IV subarachnoid hemorrhage.

BACKGROUND: Outcome after subarachnoid hemorrhage (SAH) in patients presenting with poor clinical grade has historically been dismal. As a result, many poor-grade patients have been excluded from early, aggressive surgery. We present a consecutive series of 27 patients with acute (less than 24 h since clinical onset) Grade IV SAH treated with early surgery. METHODS: All patients were treated with immediate ventricular drainage, rigid hemodynamic control, early angiography and surgery within 24 h of presentation. Patients were followed for a minimum of 6 months and their outcomes categorized using a four-tiered scale: 1) independent and working, 2) impaired but independent, 3) severely impaired and dependent, and 4) dead. RESULTS: Seven patients died within 48 h of admission. The remaining 20 patients survived to discharge. At the time of discharge eight of these patients were considered to be impaired but independent and twelve were considered severely impaired and dependent. At follow-up, seven patients were independent and working, six were impaired but independent, five were severely impaired and dependent, and two severely impaired patients had subsequently died. CONCLUSIONS: We conclude that urgent surgery for poor-grade SAH can produce quality survival for a higher percentage of patients than is historically reported with delayed surgery.

Induced hypervolemia and inotropic support for acute cerebral arterial insufficiency: an underused therapy.

BACKGROUND: Hypervolemia and induced systemic hypertension are generally considered the standard approach to the treatment of vasospasm. Despite evidence in favor of its efficacy, this therapy is used rarely in acute cerebrovascular occlusion. We present a case supporting this treatment paradigm. CASE DESCRIPTION: A patient developed aphasia and hemiplegia 8 h after carotid endarterectomy caused by embolic occlusion of the middle cerebral artery. Hyperdynamic/hypervolemic therapy was instituted. Serial angiograms filmed over the next 8 h demonstrated reperfusion of the hemisphere, through collateral flow. The patient's symptoms resolved. CONCLUSIONS: We believe this case demonstrates the effectiveness of hypervolemia and inotropic support in the treatment of acute embolic stroke by inducing dilatation of the leptomeningeal collateral circulation.

Treatment of blunt injury to the carotid artery by using endovascular stents: an early experience.

Identification of blunt carotid injury prior to the development of ischemic symptoms requires aggressive screening of patients at risk. The treatment of these lesions has centered around long-term anticoagulation therapy. However, studies have revealed that many of these lesions persist despite medical treatment, as does the risk of distal embolization. The authors present a series of six patients who were successfully treated by means of endovascular stent placement for nonpenetrating carotid injuries. In the authors' experience this treatment requires only temporary anticoagulation therapy, results in immediate reconstruction of the injured vessel, obliterates pseudoaneurysms, and prevents distal embolization.

Traumatic bilateral jugular vein thrombosis: case report and review of the literature.

OBJECTIVE AND IMPORTANCE: Thrombosis of the internal jugular vein (IJV) with associated elevated intracranial pressure (ICP) is a rare complication of central venous catheterization but has not been reported as a result of blunt trauma. CLINICAL PRESENTATION: An 18-year-old male patient was observed to be obtunded after an assault. The initial examination was remarkable for somnolence, bruising of the anterior neck, and diffuse, edematous swelling of the face and scalp. The results of computed tomography of the brain were normal. An angiogram obtained on the 2nd hospital day to rule out carotid injury revealed bilateral IJV thromboses to the cranial base. An ICP monitor was placed with an opening pressure of 33 mm Hg. The central venous pressure was measured to be 9 mm Hg. A catheter was passed through the left IJV thrombus and into the sigmoid sinus, where the pressure was 17 mm Hg. INTERVENTION: An intravascular stent was deployed in the left IJV. ICP rapidly normalized. A regimen of coumadin was administered to the patient for 6 weeks, at which time the stent remained patent. CONCLUSION: We conclude that traumatic jugular vein thrombosis can be associated with significant elevation in ICP and that treatment with an endovascular stent can affect the rapid correction of intracranial hypertension in patients who are candidates for anticoagulation.

Posterior circulation cerebral infarcts associated with repair of thoracic aortic disruption using partial left heart bypass.

BACKGROUND: Partial left heart bypass is widely used in the repair of traumatic aortic disruptions. We recently encountered two patients with posterior circulation infarctions after repair of traumatic aortic disruptions using heparin-less partial left heart bypass. METHODS/RESULTS: Both patients underwent interposition graft repair of thoracic aortic transections at the level of the isthmus. The first patient developed a left posterior inferior cerebellar artery infarct after a clamp time of 44 minutes. Swelling of this infarct necessitated ventriculostomy placement. The second patient developed a pontine infarct postoperatively after a cross-clamp time of 56 minutes and suffered a persistent left upper extremity paresis. CONCLUSIONS: Partial left heart bypass may have predisposed these two patients to clamp-related embolic events via the left vertebral artery. This experience warrants further surveillance to detect these infarcts which can require neurosurgical intervention. Additionally, the events suggest reconsideration of systemic anticoagulation during aortic cross-clamp times exceeding 30 minutes.

Balamuthia mandrillaris meningoencephalitis presenting with acute hydrocephalus.

The leptomyxid amoeba Balamuthia mandrillaris, previously believed to be a harmless soil-inhabiting organism, is now known to be a rare but consistently lethal cause of meningoencephalitis in humans. We report a case of amebic meningoencephalitis caused by B. mandrillaris which presented as a febrile illness with acute hydrocephalus.

Pineal region choroid plexus papilloma treated with stereotactic radiosurgery: a case study.

The treatment of a patient with a third-ventricular choroid plexus papilloma is described. This relatively unusual lesion was treated with stereotactic radiosurgery. Follow-up at 17 months demonstrates substantial reduction in tumor volume and an excellent clinical outcome. The treatment of this patient suggests that radiosurgery may be an effective alternative to open surgical resection.

Blunt carotid injury in children.

Blunt carotid injury (BCI) is a rare entity which can have devastating neurologic consequences. Little has been reported on the mechanism of injury, presentation or management of these injuries in children. We present a series of 5 children with BCI. One patient died at presentation while the remainder developed delayed infarctions. Three surviving patients developed intracranial hypertension and required intracranial pressure (ICP) monitoring. Surgical resection of infarcted tissue was required to control ICP in 2 patients. All four surviving patients are impaired but ambulatory. We propose an aggressive management strategy for BCI aimed at early detection of deficit, early angiography, anticoagulation if appropriate, and active management of ischemia including hemodynamic treatment, ICP monitoring, and active use of medical and surgical means to monitor and control intracranial hypertension.

Transcranial migration of microfixation plates and screws. Case report.

A case of transcranial, transdural migration of microplates and screws with damage to the subjacent cortex in an infant with craniosynostosis is described. The authors believe that plates and screws should be reserved for exceptional cases in which bony approximations are unstable or difficult to align by other means.

Sodium-dependent norepinephrine-induced currents in norepinephrine-transporter-transfected HEK-293 cells blocked by cocaine and antidepressants.

Transport of norepinephrine (NE+) by cocaine- and antidepressant-sensitive transporters in presynaptic terminals is predicted to involve the cotransport of Na+ and Cl-, resulting in a net movement of charge per transport cycle. To explore the relationship between catecholamine transport and ion permeation through the NE transporter, we established a human norepinephrine transporter (hNET) cell line suitable for biochemical analysis and patch-clamp recording. Stable transfection of hNET cDNA into HEK-293 (human embryonic kidney) cells results in lines exhibiting (1) a high number of transporter copies per cell (10(6)), as detected by radioligand binding and hNET-specific antibodies, (2) high-affinity, Na(+)-dependent transport of NE, and (3) inhibitor sensitivities similar to those of native membranes. Whole-cell voltage-clamp of hNET-293 cells reveals NE-induced, Na(+)-dependent currents blocked by antidepressants and cocaine that are absent in parental cells. In addition to NE-dependent currents, transfected cells posses an NE-independent mode of charge movement mediated by hNET. hNET antagonists without effect in non-transfected cells abolish both NE-dependent and NE-independent modes of charge movement in transfected cells. The magnitude of NE-dependent currents in these cells exceeds the expectations of simple carrier models using previous estimates of transport rates. To explain our observations, we propose that hNETs function as ion-gated ligand channels with an indefinite stoichiometry relating ion flux to NE transport. In this view, external Na+ and NE bind to the transporter with finite affinities in a cooperative fashion. However, coupled transport may not predict the magnitude or the kinetics of the total current through the transporter. We propose instead that Na+ gates NE transport and also the parallel inward flux of an indeterminate number of ions through a channel-like pore.

Transfusion significantly increases the risk for infection after splenic injury.

OBJECTIVES: To determine if splenectomy results in an increased risk for perioperative infection when analyzed against splenic repair and to identify factors associated with perioperative infection, respiratory complication, and admission to the intensive care unit following surgery for splenic trauma. DESIGN: Data were collected retrospectively from hospital records and analyzed using stepwise multiple logistic regression. SETTING: San Francisco (Calif) General Hospital, an urban level 1 trauma center. PATIENTS: All patients (n = 252) undergoing operation for traumatic splenic injury at San Francisco General Hospital from 1984 through 1990. Patients who died within 24 hours of presentation were excluded from the study. MAIN OUTCOME MEASURES: Perioperative infection, respiratory complications, and admission to the intensive care unit. RESULTS: Infection rates and the types of organisms yielded in cultures were similar between patients who underwent splenectomy and repair. Gram-negative and gram-positive organisms were found in equal numbers, and in no group did encapsulated organisms predominate. Splenectomy had no independent impact on any of the three outcome measures. Total blood transfusion was found to be the only independently significant variable associated with perioperative infection and respiratory complication. Total blood transfusion of more than 2 U and Injury Severity Score of greater than 25 were independently significantly associated with admission to the intensive care unit. CONCLUSIONS: The choice between splenectomy and splenic repair does not affect the risk for perioperative infection following injury, whereas blood transfusion significantly increases the risk for perioperative infection, respiratory complication, and admission to the intensive care unit.