Injury prior to neurectomy alters the pattern of autotomy in rats. Behavioral evidence of central neural plasticity

A common property of phantom limb pain is that a preamputation lesion continues to be felt in the same location of the phantom limb after amputation. A model of the phantom limb in the rat is provided by sectioning the sciatic and saphenous nerves. This procedure leads to self-mutilation of the denervated hindpaw, a behavior known as autotomy. There is strong evidence that autotomy is a response to painful or dysesthetic sensations referred to the anesthetic limb. The present study examined the hypothesis that the site of autotomy behavior can be altered by an injury given prior to denervation. Experiment 1 evaluated the effects of a thermal injury applied (under sodium pentobarbital anesthesia) to the medial or lateral hindpaw and digits before or after sciatic and saphenous nerve transections in order to determine whether autotomy is directed specifically to a previously injured site. The results revealed that autotomy onset occurred in the injured region of the paw in a significantly greater proportion of rats, compared to an uninjured control group, if the thermal injury had been induced before denervation: 100% of the rats with medial paw injury induced prior to neurectomy initiated autotomy in the medial digits, and 55.6% of rats with lateral paw injury initiated autotomy in the lateral digits. Rats injured after autotomy showed no such preference (medial, 33.3% and lateral, 37.5%) relative to the uninjured controls (medial, 33.3% and lateral, 17%). These results suggest that central cells, sensitized by the thermal injury, contribute to enhanced autotomy in the absence of further inputs from the injured paw.(ABSTRACT TRUNCATED AT 250 WORDS)     

Outpatient metrizamide myelography: prospective evaluation of safety and cost effectiveness

A group of 228 consecutive patients undergoing metrizamide myelography was prospectively evaluated for postprocedure symptoms. The observed prevalence of these symptoms concurs with previously reported inpatient studies, with the most common sequelae being exacerbation or onset of spine or extremity pain, headache, nausea, and paresthesia. Limitation of administered dose of metrizamide in lumbar myelography may slightly reduce the occurrence of common symptoms, but withdrawal of contrast medium at the completion of examination had no impact on their occurrence. There was a higher occurrence of paresthesia in cervical myelography, but otherwise there was no significant difference in symptoms between cervical and lumbar studies. Outpatient metrizamide myelography can be performed with relative safety with the potential for significant cost savings.     

Low-speed rotational angioplasty in chronic peripheral artery occlusions: experience in 83 patients. Work in progress

Between December 1986 and October 1988, 83 patients with chronic peripheral artery occlusions were treated with a new technique. In 56 patients, the superficial femoral artery was completely occluded; in 21 patients, the popliteal artery; and in six patients, the iliac artery. The length of occlusion ranged from 5 to 35 cm (mean, 12.5 cm). The duration, estimated by history, was 5-48 months (mean, 16.5 months). In seven patients, durations of 6-36 months were documented angiographically. A flexible, blunt, motor-driven rotating catheter was introduced through an 8-F sheath, and rotational angioplasty was performed at low speed (up to 200 rpm). In 49 of 60 (82%) patients in whom this new technique was used as the primary intervention, the occlusions were successfully reopened. In 23 patients in whom conventional methods had failed more than 4 weeks earlier, the success rate for rotational angioplasty was 67% (12 of 18 patients); when the time interval was less than 4 weeks, only one of five patients was treated successfully. In none of the 83 patients did a perforation occur. This new technique can reopen chronic artery occlusions with a high degree of success and without the danger of vessel-wall perforation, even after failure of conventional techniques.     

Unrecognized glucose intolerance is not associated with depression. Screening for Impaired Glucose Tolerance study 3 (SIGT 3)

Aims To understand the metabolic and temporal links in the relationship between diabetes and depression, we determined the association between depressive symptoms and unrecognized glucose intolerance. Methods In a cross‐sectional study, 1047 subjects without known diabetes were screened for diabetes or pre‐diabetes using the oral glucose tolerance test and for depressive symptoms using the Patient Health Questionnaire (PHQ). Results Mean age was 48 years, body mass index 30 kg/m²; 63% were female, 54% black, 11% previously treated for depression and 10% currently treated; 5% had diabetes and 34% pre‐diabetes. Median PHQ score was 2 (interquartile range 0–5). Depressive symptoms did not increase with worsening glucose tolerance, after adjusting for age, sex, ethnicity, body mass index, family history, exercise, education and depression treatment. Conclusions There is no association between depressive symptoms and unrecognized glucose intolerance. However, it remains possible that diagnosed diabetes, with its attendant health concerns, management issues, and/or biological changes, may be a risk for subsequent development of depression. Thus, patients with newly diagnosed diabetes should be counselled appropriately and monitored for the development of depression.     

Increased affinity of LDL for their receptors after acipimox treatment in hypertriglyceridemia

Summary The regulation of cellular LDL metabolism by hypertriglyceridemic LDL was tested before and after treatment with acipimox, a nicotinic acid derivative, in 11 type IV hyperlipidemic patients. Large, less dense LDL particles were found in plasma after acipimox treatment. HDL subfractions were only slightly modified, with an increase of dense, cholesteryl ester-enriched and triglyceride-poor HDL₃ particles. The LDL (B, E) receptor activity in human skin fibroblasts of LDL isolated before and after treatment was also evaluated. Hypertriglyceridemic LDL proved rather inefficient in regulating receptor activity, with a close to 30% lower capacity than normal LDL to inhibit receptor-mediated uptake and degradation of¹²⁵I-LDL. This abnormality was fully corrected after acipimox. The reported findings indicate that acipimox treatment in type IV patients can normalize the defective interaction of hypertriglyceridemic LDL with the LDL (B, E) receptor.     

Manual compression device for fluoroscopy

A device for manual compression and palpation during supine fluoroscopy has been designed. It enables effective use of the physiologic grasping and lever force potentials of the hand and wrist. The device permits optimal fluoroscopic palpation and compression techniques and prevents direct exposure to the lead-gloved hand.     

Isolated headache as the presenting clinical manifestation of intracranial tumors: a prospective study

Isolated headache as the presenting clinical manifestation of intracranial tumors: a prospective study. Cephalalgia 1994;1'4:270-1. Oslo. ISSN 0333-1024We prospectively studied over two years the incidence of headache as the initial and isolated clinical manifestation of adult patients suffering from intracranial tumors ( n = 183). Fifteen patients (8%) exhibited headache as their first and isolated clinical manifestation. Age, sex, neoplasm localization, or pathological diagnosis did not correlate with the presence of headache. Posterior fossa location and hydrocephalus, though not reaching statistical significance, were more frequent in patients who presented with headache as the first symptom. At the moment of diagnosis, 59 (31%) of the patients admitted to headache, though only I out of the 15 patients starting as headache still had this symptom as the only manifestation. From our experience in adults, isolated headache for longer than 10 weeks will only exceptionally be secondary to an intracranial neoplasm.