Heterogeneity of popular boys: antisocial and prosocial configurations.

This study examined subtypes of popular 4th-6th grade boys (N = 452). Popular-prosocial (model) and popular-antisocial (tough) configurations were identified by means of teacher ratings and compared with peer and self-assessments and social centrality measures. Peers perceived model boys as cool, athletic, leaders, cooperative, studious, not shy, and nonaggressive. Peers perceived tough boys as cool, athletic, and antisocial. Model boys saw themselves as nonaggressive and academically competent. Tough boys saw themselves as popular, aggressive, and physically competent. Tough boys were disproportionately African American, particularly when African Americans were a minority in their classrooms. Model and tough boys were overrepresented at nuclear social centrality levels. These findings suggest that highly aggressive boys can be among the most popular and socially connected children in elementary classrooms.

Clinical assessment of a novel antiadhesion barrier gel: prospective, randomized, multicenter, clinical trial of ADCON-L to inhibit postoperative peridural fibrosis and related symptoms after lumbar discectomy.

A prospective, multicenter, randomized, double-blind, controlled study of ADCON-L Anti-Adhesion Barrier Gel (a medical device by Gliatech Inc, Cleveland, OH) was conducted in 298 patients undergoing first-time lumbar discectomy to evaluate the safety and effectiveness of ADCON-L in preventing postoperative peridural fibrosis and in improving patient clinical outcome. After lumbar discectomy, patients were randomized to receive either ADCON-L gel or nothing (control group) at the conclusion of the surgical procedure. Six months after surgery, peridural scar was evaluated by magnetic resonance imaging, and postoperative pain and straight-leg-raise angle were assessed. No statistically significant differences between the ADCON-L and control groups were observed in terms of adverse events or wound healing characteristics. ADCON-L gel was shown to be safe and to significantly inhibit peridural scar compared with the control group (P = 0.002). That peridural scarring was reduced with ADCON-L gel was further supported by direct visualization of scar tissue at reoperation in both groups. ADCON-L-treated patients had better clinical outcomes than did control patients. The incidence of activity-related pain was significantly reduced (P = 0.013), straight-leg-raise examination scores were significantly improved (P = 0.024 on the operative side and P = 0.015 on the nonoperative side), and ADCON-L reduced low back pain when it was most severe (P = 0.047) and at the end of the day (P = 0.044).

The clinical significance of gadolinium enhancement of lumbar disc herniations and nerve roots on preoperative MRI.

The clinical significance of preoperative gadolinium DPTA enhancement around disc herniations and in the epidural space on MRI is not clear. The relation of nerve root enhancement to dysfunction also remains controversial. To investigate the clinical significance of contrast enhancement we looked at the symptoms and signs and gadolinium DPTA-enhanced images of 71 consecutive surgical candidates in a standardised fashion. Annular rupture and disc enhancement were found to be closely related, and correlated with sensory loss and paresis, respectively. Nerve root enhancement was found to be related to neurological deficits in general and sensory impairment in particular.

Anterior cervical discectomy with or without fusion with acrylate. A randomized trial.

STUDY DESIGN: A prospective randomized trial with assessment of treatment results by an independent observer and by patient questionnaire. OBJECTIVES: This study evaluated whether implantation of polymethylmethacrylate after anterior cervical discectomy improved clinical results and whether polymethylmethacrylate provided a solid bony union with preservation of anatomical relations of the cervical spine. SUMMARY OF BACKGROUND DATA: Discectomy without fusion disturbs anatomical relations of the cervical spine. Use of an autologous bone graft frequently causes donor-site complications. Therefore, synthetic materials such as polymethylmethacrylate have been used instead of bone to obtain spinal fusion. Whether these implants improve the clinical results of anterior discectomy is unknown. In addition, the radiological follow-up of discectomy with polymethylmethacrylate has hardly been investigated. METHODS: Between April, 1986, and April, 1990, all patients with radiologically proven cervical disc pathology and a radicular syndrome were eligible for this study. The primary endpoint of the study was the clinical result after 2 years. Assessment of the result was rated both by an independent observer using Odom's criteria and by the patient using a written questionnaire. Before surgery and during follow-up, radiographs were obtained. RESULTS: Two patients died during follow up. A good result was obtained in 28 of 42 patients (70%) treated with polymethylmethacrylate and in 30 of 39 patients (77%) of patients treated with discectomy only. Pre-operative neck pain subsided earlier if polymethylmethacrylate was used, but the difference was temporary and clinically insignificant. The use of polymethylmethacrylate resulted in a significant lower bony union rate. Polymethylmethacrylate frequently migrated into adjacent vertebrae. CONCLUSIONS: No relevant clinical differences between treatments were found. The radiological results of anterior discectomy with polymethylmethacrylate were inferior to those of discectomy only. Based on these results, the use of polymethylmethacrylate to obtain fusion after anterior discectomy is not recommended.

Stressful events and individual beliefs as correlates of economic disadvantage and aggression among urban children.

This study examined 3 factors that were hypothesized to increase risk for aggression among urban children: economic disadvantage, stressful events, and individual beliefs. Participants were 1,935 African American, Hispanic, and White elementary-school boys and girls assessed over a 2-year period. The relation between individual poverty and aggression was only significant for the White children, with significant interactions between individual and community poverty for the other 2 ethnic groups. With a linear structural model to predict aggression from the stress and beliefs variables, individual poverty predicted stress for African American children and predicted beliefs supporting aggression for Hispanic children. For all ethnic groups, both stress and beliefs contributed significantly to the synchronous prediction of aggression, and for the Hispanic children, the longitudinal predictions were also significant. The findings are discussed in terms of their implications for preventive interventions in multiethnic, inner-city communities.

Ultrasonography in acute interstitial laser irradiation of the pig brain: preliminary results.

In this preliminary study, the use of real-time ultrasonography to visualize the effects of acute interstitial Nd:YAG laser irradiation was investigated in the normal pig brain. In six pigs, a craniotomy was performed. In the frontal or temporal lobe, a thermal laser lesion was made using a 600-micron-diameter optical fiber at powers of 1 W, 2 W, and 4 W with exposure times of 5 min and 10 min. Ten to thirty minutes after laser irradiation, the pigs were sacrificed. Ultrasound imaging was performed before, during, and after laser irradiation. During laser irradiation, a clear hyperechogenic area was observed around the fiber tip. The onset of the changes and the extent of the lesion were dependent on the power and exposure time. Histologic examination showed thermal lesions consisting of coagulation necrosis and edema. The size of the lesions correlated well with size on ultrasound imaging. The maximal lesion dimension was 12 mm in diameter (4 W for 5 min). In conclusion, within the limitations of this experimental setup, it is feasible to visualize interstitial laser-induced lesions in the brain by ultrasonography. This method is safe and simple and may be helpful in future applications of interstitial thermotherapy in brain tissue.

Clinical observations with a dual sensor rate adaptive single chamber pacemaker.

The Topaz model 515 (Vitatron B.V.) is a dual sensor rate responsive pacemaker for single chamber stimulation. It can be driven by activity counts (ACT) and QT interval measurements. Inappropriate rate modulation due to one sensor can be corrected by "sensor cross-checking." It was implanted in ten patients (20-86 years) of whom seven had complete heart block and atrial arrhythmias. After implantation T-wave amplitude ranged from 0.9 mV-3.5 mV. T-wave sensing ranged from 88%-99% in 9/10 patients at the follow-up of 3 weeks. Eight patients remained in default setting of the activity threshold, after evaluation with a short walking test. An exercise test was performed on all patients. In one test, QT sensing was marginal because of lead implantation in the right ventricular outflow tract. Therefore, this pacing rate was only modulated by ACT sensing. All others were tested with equal contribution of information from both sensors (ACT = QT). In 7/9, rate response was satisfactory. When the treadmill was repeated with ACT in five of these seven patients, rate generally accelerated too fast. In one patient the setting was adjusted to "QT > ACT," because of inappropriate acceleration due to activity sensing, in another it was adjusted to "QT < ACT" because of delayed response to activity. The pacing rate and the ACT during treadmill tests in "QT = ACT" mode were more closely correlated in the first 3 minutes, compared with the last 3 minutes. We feel that rate modulation with this new pacemaker is adequate. Sensor blending and sensor cross-checking are of clinical importance.

Rett syndrome: a review of current knowledge.

Rett syndrome was first described in 1966 by Andreas Rett. To date, this syndrome has been reported only to afflict females. The disorder is characterized by a progressive loss of cognitive and motor skills as well as the development of stereotypic hand movements, occurring after an apparently normal 6 to 18 months of development. Although Rett syndrome is thought to afflict as many as 10,000 girls in the United States, fewer than 1,200 have been identified thus far. A lack of awareness of this disorder is thought to play a critical role in the failure to differentially diagnose this syndrome. The present article presents a review of our current knowledge concerning this disorder. Information is provided related to the clinical manifestations, etiology, prevalence, pathogenesis, and treatment of the Rett syndrome.

Normal pressure hydrocephalus: did publications alter management?

Forty six Dutch neurologists and neurosurgeons were interviewed to evaluate the clinical value of research articles on normal pressure hydrocephalus (NPH). From this survey it appears that most clinicians still limit investigations to psychometry, CSF-tap test(s), and cisternography. The main reasons for not using other techniques were: their invasiveness, technical complexity, poor availability, lack of time and doubt on their additional predictive value. There is an obvious discrepancy between the quantity of publications on NPH and their impact and their ability to assist clinicians in selecting potential NPH patients for a shunt.

[Anterior discectomy as treatment for a cervical radicular syndrome]. / De anterieure discectomie als behandeling voor een cervicaal radiculair syndroom.

The results are presented of a retrospective survey of anterior cervical surgery followed by fusion with autologous bone grafting for the treatment of radiculopathy due to cervical intervertebral disc prolapse or spondylosis. The study included 46 patients, with a follow-up period of at least a year. Follow-up examination was performed by an independent observer. Of the patients 38 (83%) were improved, 34 (74%) having a 'good' or 'excellent' response. Postoperative complications were minor; the most frequent complication was pain or dysaesthesia at the donor site of the bone graft, the iliac crest. It is questionable whether autologous bone grafting is indicated following anterior discectomy.

Gliomas: new ways of treatment?

Evidence starts to appear that immune reactions may be important in the development and growth of gliomas. The purpose of this article is to review this evidence and to mention its implications for the future.