Characterization of a purified nicotinic receptor from rat brain by using idiotypic and anti-idiotypic antibodies

The availability of an anti-nicotine monoclonal antibody has made it possible to further establish the nature of the nicotine recognition proteins purified from rat brain by affinity chromatography and to provide a highly sensitive assay for determining [3H]nicotine binding to the purified material. An enantiomeric analogue of nicotine, (-)-6-hydroxymethyl-nicotine, was used to prepare the affinity column. In addition, with the use of anti-idiotypic monoclonal antibody, it was confirmed that the recognition site for nicotine resides on a protein complex composed of two components with molecular masses of 62 and 57 kDa. It was also demonstrated that the same two proteins could be purified by immunoaffinity chromatography with the use of an anti-idiotypic monoclonal antibody. With the use of the anti-nicotine antibody to measure [3H]nicotine binding, the purified material was shown to bind 250 pmol/mg of protein. By utilizing a procedure in which the purified receptor protein was conjugated to membranes by disulfide bonds, a binding activity of 80 pmol/mg was obtained. With the availability of stereospecific monoclonal antibodies to (-)-nicotine as well as monoclonal anti-idiotypic antibodies derived when the anti-nicotine antibodies were used as immunogens, additional procedures became available for the further characterization of the purified nicotine receptor and examining its (-)-[3H]nicotine-binding characteristics.

Extensive scalds following accidental immersion in hot water pools

The scalds produced by immersion in hot water pools were extensive, usually of superficial depth on the upper parts of the body and deep dermal or full thickness skin loss on the lower parts. Blisters appeared rather slowly, within 2 days post-burn and often dispersed spontaneously. The estimated burned area on admission may thus be smaller than found subsequently. This study showed that the volume of fluid required for adequate resuscitation during the first post-burn day may be only 1.5 ml/kg/% BSA burned. Deep dermal burns were treated preferably by early tangential excision and grafting. The full thickness skin loss was treated by escharectomy and skin grafts.

Operating characteristics and applications of a microchannel spatial light modulator under white-light illumination

A microchannel spatial light modulator-based white-light optical processor is presented. The basic principle of the system performance is studied. The operating characteristics of the spectral and contrast responses are measured. Applications to real-time optical processing operations which include the intensity color encoding analog hard clipping in colors are provided.

Receptor binding characteristics of a 3H-labeled azetidine analogue of nicotine

A new radioligand, (+/-)-[3H]-1-methyl-2-(3-pyridyl)-azetidine, which is an analogue of nicotine, has been used to investigate the binding characteristics of the nicotine receptor in rat brain membranes. By Scatchard analysis, the azetidine analogue yielded a curvilinear plot with Kd values of 7 X 10(-11) and 1.7 X 10(-9) M and Bmax values of 0.3 X 10(-14) and 2.5 X 10(-14) mol/mg protein respectively. Thermodynamic analyses yielded negative free enthalpy values for both sites, a decrease in the Bmax of only the lower affinity site, and no effect on either Kd. The psychotropic potency (prostration in rats following intraventricular injection) of the azetidine analogue was about 5-fold greater than (-)-nicotine, being among the greatest of any known nicotine analogues tested to date. Since only the higher affinity Kd differed from that of (-)-nicotine, 3-fold greater, the psychotropic potency appears to be correlated with the higher affinity site. Insofar as [3H]methylcarbamylcholine, a nicotinic ligand resembling acetylcholine, exhibits a linear Scatchard with a Kd of 1 X 10(-9) M, the higher affinity site appears to be characteristic of nicotine analogues.

Total reconstruction of the ear with auditory function: a two stage procedure

The rational treatment of severe microtia or anotia should be to restore not only the form but also the auditory function of the ear. To achieve this aim it is obvious that plastic surgeons must co-operate closely with an otologist: yet this degree of co-operation is seldom seen. This paper describes a two-stage procedure for total ear reconstruction with auditory function. In stage I, a tympanoplasty is performed before transplantation of the carved cartilage framework. Stage II consists of elevation of the reconstructed auricle and transplantation of a full-thickness skin graft to the post-auricular defect. Certain modifications of the operative techniques that we have found useful are discussed in detail.

Clinical and histological observations on the application of intermingled auto- and porcine-skin heterografts in third degree burns

Escharectomy and skin grafting with both homograft and porcine skin has become an effective method in treating massive third degree burns. Seventeen patients and 21 operations of intermingled transplantation of auto- and fresh porcine skin heterografts after escharectomy of the severe burn wounds have been carried out since March 1973. Clinical and histological data are summarized, among which we observed the 'fusing phenomena' of auto- and porcine skin heterografts in 6 patients. Vascularization, 'turning red', viability and rejection as well as ways to improve the results of the grafting method are discussed. No vascular communication between fresh porcine skin and the host wound has been observed during the early postoperative period. The cause of 'turning red' is a reddish transudation between the graft and the host wound seen through the thin porcine skin. Based on histological observations, porcine skin is viable after transplantation. With nutritional support apparently coming from the underlying plasma and tissue fluid. Eventually the process of rejection is similar to that of homograft Better results are found with porcine skin grafts 0.4-0.5 mm in thickness placed 0.5-0.75 cm apart. In order to avoid large sloughing wound surfaces less than 20 per cent area of porcine skin coverage is advisable.

The primary hamster kidney cell rabies vaccine: adaptation of viral strain, production of vaccine, and pre- and postexposure treatment

The hamster kidney cell rabies vaccine was investigated as a substitute for classical nervous tissue rabies vaccine. The Beijing strain of fixed rabies virus was adapted to primary hamster kidney cells (PHKCs), and four types of rabies vaccine (plain, adjuvant, concentrated, and concentrated adjuvant vaccines) were developed for human use. The potencies of the vaccines met the requirements of the World Health Organization, and these vaccines elicited rather satisfactory antibody responses in volunteers. The postexposure use of vaccine was evaluated in 301 individuals, 97 of whom had been bitten by proven rabid animals. None of the individuals contracted rabies during the observation period. After several years of field trials with both pre- and postexposure vaccines, the evidence indicates that the PHKC rabies vaccines are effective and safe for human use.