Characterization of activities and forms of cholinesterases in human primary brain tumors

The activities and molecular forms of cholinesterases were studied in a collection of primary brain tumors consisting of primarily gliomas and meningiomas, together with samples of forebrain taken postmortem from patients suffering from diseases unrelated to the nervous system. Both types of tumors, as well as normal forebrain, contained substantial amounts of cholinesterase activity and some gliomas contained exceptionally high levels. In both normal forebrain and meningiomas, acetylcholinesterase (acetylcholine hydrolase; EC 3.1.1.7) accounted for almost all the cholinesterase activity, but in almost all gliomas elevated pseudocholinesterase (acylcholine acylhydrolase; EC 3.1.1.8) could be detected. The cholinesterase activity of both normal forebrain and gliomas migrated on sucrose gradients as a major component of 10–11 S together with a minor component of 4–5 S. In meningiomas a light (4.5 S) form was the principal component.     

Transcervical removal of a clivus chordoma in a 2-year-old child. Reversal of quadriplegia and bulbar paralysis

Summary The successful removal of a low clivus chordoma in a 2-year-old child via the anterior transcervical-transclival approach is reported. Diagnostic difficulties due to the sudden onset and progression masquerading as a viral neurological disease are briefly discussed.The cranio-spinal instability following the operations in our case implies that reconstructive cranio-spinal surgery will be necessary in the future provided that the tumour does not rapidly recur.     

Stimulatory effect of He-Ne low dose laser on injured sciatic nerves of rats

Injury to a mammalian peripheral nerve is accompanied by a restorative process that is manifested after a delay. This process is expressed morphologically by the emergence of new nerve fibers. Restoration of function occurs when the regenerating fibers reconnect with the target organ. Because of the low rate of fiber elongation, the denervated target is partially degenerated by the time that the regenerating fibers approach it. To prevent such an atrophy, one must find a way to prevent the degeneration of the nerve, to speed up regeneration, or to maintain the target during the period of nerve degeneration. In the present work, we examined the potential of treatment with low energy laser radiation for improving regeneration or preventing degeneration of mammalian peripheral nerve after injury. After repeated injury for 20 consecutive days, treatment of the sciatic nerve of the rat with low energy laser (He-Ne, 17 mW) caused a significant increase in the amplitude of the action potential recorded in the corresponding gastrocnemius relative to the action potential of injured but not treated nerves. The action potential of the injured sciatic nerves that were laser-irradiated increased to values close to that of a noninjured nerve. The studies include follow-up for 1 year after the injury. This electrophysiological manifestation of the effect of laser treatment on injured nerves was accompanied by a diminution of the size of the scar tissue from these nerves. Yet to be resolved is whether these two phenomena (i.e., electrophysiological and morphological responses) coincide or whether they relate to each other.(ABSTRACT TRUNCATED AT 250 WORDS)     

Competitive ELISA for detection of native ras gene-related products in sera of cancer patients

A solid phase, enzyme-linked immunosorbent assay (ELISA) competition kit was developed to detect circulating native ras gene-related products in sera of 151 healthy volunteers and cancer patients. This assay uses monoclonal antibody (mAb) BST-6A generated against a yeast-derived, native ras-related polypeptide Yp20. Only 2% (1 of 58) of normal control sera showed strong competition, as compared to 15% (5 of 34) of patients with early stage or no evidence of disease, and 44% (26 of 59) of patients with advanced disease. These differences were statistically significant (x2, P less than 0.05-0.001). Eleven sera samples of cancer patients found to be strong competitors in the ELISA competition kit were tested for the presence of anti-ras antibodies by ELISA. None showed higher ELISA values as compared with pooled normal human serum and control sera. It is thus suggested that our procedure detected circulating ras-related onco-proteins in sera of cancer patients mainly with advanced disease.     

Detection of retroviral particles in hybridomas secreting monoclonal antibodies

Electronmicroscopy of hybridoma clones derived by fusing BALB/c mouse spleen cells with P3U1 mouse plasmacytoma cells to generate monoclonal antibodies against human sarcoma antigens, revealed the presence of large number of viral particles. These particles were also seen budding from the cell surfaces. The intracytoplasmic particles were intracisternal and resembled type-A oncornavirus, while the budding and extracellular forms, with a centrally located nucleoid, resembled mature type-C oncornaviruses. Cells of the parental P3U1 palsmacytoma cell line and of the NS-1 myeloma cell line contained morphologically identical viral structures. The scientific and medical communities engaged in hybridoma research should be alert to the possible presence of viruses in hybridomas and their products. The question is raised as to whether it is safe to use mouse monoclonal antibodies for clinical purposes, both diagnostic and therapeutic.     

Compression (Salter-Harris Type V) physeal fracture: an experimental model in the rat.

Histologic evidence of damage to the proximal tibial physis of immature rats was documented in greater than 30% of hind limbs subjected to a valgus and compressive force. The lesion was consistent with that theorized for the Salter-Harris Type V fracture. Two additional groups of immature rats were subjected to the same insult and followed to maturity. One of the groups sustained an intentional concomitant ipsilateral femoral shaft fracture. No tibia demonstrated a growth disturbance in the absence of the femoral fracture, while similar angular deformities were noted in four tibiae (13%) in the presence of a fractured femur. Previously theorized traumatic physeal injuries, implicated in subsequent growth disturbances and seen clinically in association with ipsilateral long bone fractures, were identified in this animal study.     

Malignant melanoma appearing in a post-mastectomy lymphedematous arm: a novel association of double primary tumors

The association of a malignant melanoma appearing as an additional primary tumor in the swollen arm adjacent to a mastectomy for breast cancer is reported. A review of the literature revealed only one similar patient previously reported. In both patients, the melanoma and its metastasis were restricted to the lymphedematous arm, appeared 10 years post-mastectomy, and responded to therapy. The similarity to Stewart-Treves syndrome is emphasized. It is suggested that nevi developing in the lymphedematous arm post-mastectomy should be carefully monitored and excised early whenever indicated.     

Response of peripheral nerve to He-Ne laser: experimental studies

Low-energy He-Ne laser irradiation (LELI) was found to affect the electric activity and morphology in both intact and severely injured peripheral nerves in rats. Action potential (AP) in the healthy nerve increased by 33% following a single transcutaneous irradiation. Similar irradiation in crushed nerves caused AP to increase significantly over the AP of nonirradiated crushed nerve. Morphological observations revealed that a laser-irradiated injured nerve had diminished scar tissue as compared to an injured but not an irradiated nerve.     

Oral administration of the methanol extraction residue of BCG (MER/BCG): a phase I study in non-oat cell lung cancer patients

Intradermal, interlesional and intravenous MER/BCG have been reported to possess immunostimulatory properties and combined with chemo-radiotherapy an anti-neoplastic effect. Due to local and systemic side effects of the methanol extraction residue of BCG therapy a new approach to oral administration was investigated. Seventeen patients with inoperable non-oat cell lung cancer were given oral MER for 30 days. Skin tests to 5 recall antigens and various concentrations of MER, lymphocyte stimulation by PHA were done before and repeated during therapy. The initial group of patients received a dose of 1.25 mg per day and when no side effects were detected the dose was gradually escalated in subsequent groups of patients up to 5 mg. Oral MER was well tolerated even at the higher dose with no clinical or laboratory side effects. No regression in tumor size was seen. In 6 of 17 patients the disease remained stationary for a mean of 6 months (Range 6-14 months). In the remainder, disease progressed after a mean of 15 weeks. Two patients had cutaneous PPD reactivity converted from negative to positive, in one it became negative, while the remaining patients maintained their original responsiveness. No major changes could be observed in the in vivo immune tests performed following the course of treatment. In view of the reported relative efficacy of oral BCG administration, and considering the very low toxicity with oral MER, further studies employing considerably higher doses of this nonviable vaccine are now justified.