Silicone tubing used in intubating the lacrimal system. Joining the ends for easy removal

Experiments were conducted in rabbits using histoacryl glue to join the ends of the silicone tubing used to intubate the lacrimal system. This method avoids the need for knots of suture which occasionally become trapped in the lacrimal sac, making extubation difficult. Rabbits intubated with this method were compared with those intubated with tubing tied by 4-0 prolene suture and untreated controls. The new method was successful during the four months of our study and no significant histopathological effects were observed in the normal canaliculus. The success of the procedure in rabbits led to its use in ten infants with lacrimal obstructions that had not been relieved by previous probings.     

Protection by GAB A Agonists, γ-Hydroxybutyric Acid, and Valproic Acid Against Seizures Evoked in Epileptic Chicks by Hyperthermia

With microwave diathermy, febrile seizures were produced in epileptic chicks aged 2-5 days. Drugs that enhance GABAergic activity (i.e., GABA, muscimol, and progabide), as well as valproic acid and gamma-hydroxybutyric acid, produced dose-dependent increases in latency to onset of seizures.     

Unidirectional replication of a minority of polyoma virus and SV40 DNAs.

Poyoma DNA replication is initiated predominatly at a site which is 29% from the EcoRI cleavage site. Molecules replicating from this site, after digestion with EcoRI appear as linear structures with a double stranded loop centered at the origin of replication. These forms constitute 90% of all replicating intermediates. Approx. 10% of the replicating intermediates of polyoma and SVP40 DNAs occur as Y-forms after treatment with EcoRI. These structures have probably resulted from unidirectional replication initiated at an additional origin of DNA replication which is located near the EcoRI cleavage site on the genomes of these viruses.     

Very-high-dose phenobarbital for refractory status epilepticus in children

Status epilepticus refractory to initial anticonvulsant therapy is a serious condition with a high morbidity and mortality. We present 50 cases with refractory status epilepticus (RSE) treated with very-high-dose phenobarbital (VHDPB) without reference to a predetermined maximum level or dose. Maximum serum levels ranged from 70 to 344 micrograms/ml (median, 114 micrograms/ml). VHDPB controlled seizures in all cases where no limits were imposed upon maximum dose (47/50). We found no maximum dose beyond which further doses are likely to be ineffective. Forty patients were intubated prior to VHDPB, but recovered respiratory drive and could be removed from the ventilator despite very high serum levels. This is explained by acute drug tolerance. Hypotension was unusual, related to the highest levels, and easily controlled. VHDPB has many relative advantages over other therapies presently used for RSE.     

Electrophoretic analysis of red blood cells in polycythaemia

In contrast with previously published observations, this study has found no increase in the net negative surface charge of the red blood cells (RBC) from patients with various forms of polycythaemia when compared with normal subjects. Two sub-populations of RBCs with different electrophoretic mobilities (EPM), termed fast and slow, were present in samples from both patients and normal individuals. Frequently, the slow cell population in RBCs from patients with polycythaemia, particularly the apparent polycythaemia sub-group, was of a lower EPM and contained more cells than the corresponding population in normal subjects. The membrane-bound sialic acid content of RBCs from patients with primary proliferative polycythaemia, associated with iron deficient RBC changes, was increased if the results were expressed per unit volume of RBCs and decreased if the sialic acid concentration was presented per number of RBCs. These results imply that differences in surface charge of RBCs are of no value in discriminating between primary and secondary polycythaemia.     

Intraabdominal desmoplastic small-cell tumors with divergent differentiation. Observations on three cases of childhood

We studied three intraabdominal tumors that manifested in childhood and were attached to peritoneum, and in which the histologic pattern suggested metastatic tumor of epithelial nature but gave no evidence of a primary neoplasm in the major abdominal organs. Follow-up observation lasted from 1 to 6 years but never disclosed a primary site. Histologic, immunohistochemical, and electronmicroscopic observations indicated a primitive malignant neoplasm of uncertain histogenesis capable of simultaneously expressing epithelial, mesenchymal, and, less consistently, neural phenotypes. In childhood, the possibility of embryonic neoplasm, such as nephroblastoma occurring in atypical sites, is difficult to exclude. Despite the prevailing uncertainty about histogenesis, combined therapy achieved an apparent cure in one of our cases.     

Subtalar stabilization of the planovalgus foot by staple arthroereisis in young children who have neuromuscular problems

A new approach was developed for the treatment of planovalgus feet in children who have spastic cerebral palsy and are less than six years old. The procedure consists of subtalar stabilization (arthroereisis) with a Vitallium staple, and it corrects alignment, restores balance, and allows continued function. It is safe, technically simple, and efficient. Between 1980 and 1988, forty-eight arthroereises were done. The results of thirty-one procedures in twenty patients who were two to ten years and ten months old at the time of the operation were followed for an average of 4.1 years (range, two to seven years). Approximately 85 per cent of the results were excellent or good. Only one foot needed a revision; this was due to migration of the staple. At the most recent follow-up, the talocalcaneal angle had not changed in about 50 per cent of the feet. In another seven, the change ranged from 5 to 10 degrees. All of these patients had a satisfactory result. In all but three feet, the goal of maintaining the stability of the talocalcaneal joint without orthotics or osseous fusion was achieved. Originally, the procedure was done only in patients who were less than six years old, but, because of its success, the indications were extended to children of any age who had severely involved and neurologically compromised feet. Satisfactory results were obtained in the older children as well.