Recent Publications by CFE Educators

Treatment of acute ischemic stroke with intravenous tissue-type plasminogen activator is underutilized partly due to the risk of life-threatening hemorrhage. In response to the clinical need for safer stroke therapy, we explored using an aptamer-based therapeutic strategy to promote cerebral reperfusion in a murine model of ischemic stroke. Aptamers are nucleic acid ligands that bind to their targets with high affinity and specificity, and can be rapidly reversed with an antidote. Here we show that a Factor IXa aptamer administered intravenously after 60 minutes of cerebral ischemia and reperfusion improved neurological function and was associated with reduced thrombin generation and decreased inflammation. Moreover, when the aptamer was administered in the setting of intracranial hemorrhage, treatment with its specific antidote reduced hematoma volume and improved survival. The ability to rapidly reverse a pharmacologic agent that improves neurological function after ischemic stroke should intracranial hemorrhage arise indicates that aptamer-antidote pairs may represent a novel, safer approach to treatment of stroke.

Glomuvenous malformations are hereditary vascular anomalies, usually without extracutaneous involvement. We report two cases of extensive thoracic plaque-type glomuvenous malformation in newborns who had previously been diagnosed in utero with pleural effusion and ascites, suggesting a pathogenic link between the two conditions.

Dorsal root ganglia (DRG) neurons, including the nociceptors that detect painful thermal, mechanical, and chemical stimuli, transmit information to spinal cord neurons via glutamatergic and peptidergic neurotransmitters. However, the specific contribution of glutamate to pain generated by distinct sensory modalities or injuries is not known. Here we generated mice in which the vesicular glutamate transporter 2 (VGLUT2) is ablated selectively from DRG neurons. We report that conditional knockout (cKO) of the Slc17a6 gene encoding VGLUT2 from the great majority of nociceptors profoundly decreased VGLUT2 mRNA and protein in these neurons, and reduced firing of lamina I spinal cord neurons in response to noxious heat and mechanical stimulation. In behavioral assays, cKO mice showed decreased responsiveness to acute noxious heat, mechanical, and chemical (capsaicin) stimuli, but responded normally to cold stimulation and in the formalin test. Strikingly, although tissue injury-induced heat hyperalgesia was lost in the cKO mice, mechanical hypersensitivity developed normally. In a model of nerve injury-induced neuropathic pain, the magnitude of heat hypersensitivity was diminished in cKO mice, but both the mechanical allodynia and the microgliosis generated by nerve injury were intact. These findings suggest that VGLUT2 expression in nociceptors is essential for normal perception of acute pain and heat hyperalgesia, and that heat and mechanical hypersensitivity induced by peripheral injury rely on distinct (VGLUT2 dependent and VGLUT2 independent, respectively) primary afferent mechanisms and pathways.

OBJECTIVE

To evaluate the incidence and risk factors for bladder neck contracture (BNC) in men treated with robot-assisted laparoscopic radical prostatectomy (RALP) and open radical prostatectomy (ORP), as BNC is a well-described complication of ORP and may be partially attributable to technique.

PATIENTS AND METHODS

The University of California San Francisco Urologic Oncology Database was queried for patients undergoing RALP or ORP from 2002 to 2008. Patient demographics, prostate cancer-specific information, surgical data, and follow-up were collected. For each surgical approach, multivariate Cox proportional hazards regression was performed to evaluate associations of demographics and clinical characteristics with BNC. Time to BNC after RP was evaluated using life table and Kaplan-Meier methods.

RESULTS

From 2002 to 2008, 988 patients underwent RP as primary treatment and had at least 12 months of follow-up. Of these men, 695 underwent ORP and 293 underwent RALP. The mean (sd) age was 59.3 (6.80) years and 91% of men were Caucasian. D'Amico risk groups at diagnosis were low (38%), intermediate (38%), and high (24%). The BNC incidence was 2.2% (22 cases) overall, 1.4% (four) for RALP, and 2.6% (18) for ORP (P= 0.12). Patients with BNC were diagnosed a median (range) of 4.7 (1-15) months after surgery. At 18 months after surgery, the BNC-free rate was 97% for ORP and 99% for RALP (log-rank P= 0.13). The most common presenting complaint was slow stream, followed by urinary retention. In Cox proportional hazards regression analysis, earlier year of surgery, older age at diagnosis and higher PSA level at diagnosis were significantly associated with BNC among ORP patients. In the RALP group, none of the covariates were associated with BNC.

CONCLUSIONS

The overall incidence of BNC was low in both RALP and ORP groups. Technical factors such as enhanced magnification and a running bladder anastomosis may explain the lower BNC incidence in the RALP group.

OBJECTIVE

To study whether long-term treatment with oestrogen (E(2) ), selective E(2) receptor modulators (SERMs), or growth hormone (GH) can prevent the development of abnormal voiding patterns during filling cystometry (CMG) in a postpartum, ovariectomized (Ovx) female rat.

MATERIALS AND METHODS

Immediately after spontaneous delivery, 60 primiparous Sprague-Dawley rats were randomly divided into six equal groups. One group served as uninjured sham controls and five groups underwent intravaginal balloon dilatation. On day seven, previously dilated rats underwent bilateral Ovx and implantation of a subcutaneous hormone-delivery pump. The five treatment groups received normal saline (control), E(2) , raloxifene, levormeloxifene, or GH for 7 weeks. Conscious CMG was performed 7 weeks after Ovx. Urethral sphincter tissue was harvested for elastin immunohistochemistry and real-time polymerase chain reaction of α(1A) -adrenoceptor mRNA.

RESULTS

No abnormal voiding patterns were detected in the group treated with GH. The E(2) , raloxifene and levormeloxifene groups had greater detrusor overactivity and urethral relaxation incontinence than control rats. The raloxifene group had a significantly lower baseline bladder pressure and opening pressure. GH-treated rats had higher elastin content in the urethra. Urethral α(1A) -adrenoceptor mRNA concentration was significantly lower in the SERM-treated rats compared with controls.

CONCLUSIONS

GH prevents the development of abnormal voiding patterns during filling CMG in a rat model of parturition-induced incontinence; E(2) and SERMs may worsen voiding patterns.