Resonance Raman-spectroscopic studies of the hapten features involved in the binding of 2,4-dinitrophenyl haptens by the mouse myeloma proteins MOPC 315 and MOPC 460

The binding of four dinitrophenyl haptens to the mouse myeloma proteins MOPC 315 IgA (immunoglobulin A) and MOPC 460IgA was studied by resonance Raman spectroscopy. Isotopic substitution with 15N and 2H was used to assign features in the resonance Raman spectra of the free haptens. Changes in each of these features on binding to the proteins could then be attributed to interactions of the proteins' binding sites with either the p-NO2 or the o-NO2/amine regions of the haptens. The interactions between a given hapten and MOPC 315 IgA are often quite distinct from those between the same hapten and MOPC 460 IgA. Moreover, for both antibodies the nature of the R side chain in a Dnp-NHR (Dnp, 2,4-dinitrophenyl) compound appears to modify the interactions between the Dnp chromophore and the protein. Thus, with the haptens studied, there is no unique set of contacts between the Dnp group and the binding site. The contacts expected between epsilon-2,4-dinitrophenyl-L-lysine and the site on MOPC 315 IgA, on the basis of a recent model for this site [Dwek, Wain-Hobson, Dower, Gettins, Sutton, Perkins & Givol (1977) Nature (London) 266, 31--37] were not detected. However, the contacts between this hapten and the site on MOPC 460 IgA were closer to those predicted by the model for MOPC 315 IgA.

Resonance Raman labels: spectroscopic studies on cis- and trans-4-benzylidene-2-phenyl-Δ2 -oxazolin-5-one and an isotopically substituted analog

The absorption and preresonance Raman spectra of cis- and trans-4-benzylidene-2-phenyl-Δ2-oxazoIin-5-one are reported. Although steric considerations suggest that the π electron pathway in the cis isomer is considerably distorted compared to the trans isomer, the Raman and absorption spectra of the two isomers are strikingly similar. Preresonance Raman excitation profiles for the cis and trans isomers indicate that the main features in the Raman spectra owe their intensity to coupling to the 360 nm absorption band present in both isomers. It is proposed that both the electronic dipole transition responsible for this absorption and the vibrational modes giving rise to the intense Raman bands are localized in the —C=C—N=C—Ph part of the molecule. Thus the main Raman and absorption bands are insensitive to isomerization in the benzylidene portion. Support for a localized electronic transition, polarized along the —C=C—N=C—Ph long axis, comes from Raman depolarization ratio (ρ) measurements which show that ail intense Raman features in both cis and trans isomers have ρ ∼ 0.33. Further support comes from ir and resonance Raman spectra of trans-4-(4-dimethylamino-3-nitrobenzylidene)-2-phenyloxazolin-5-one substituted either with 13C in the 4 position, or with 15N, in the oxazolinone ring. These spectra indicate that the main Raman feature seen in all 4-benzylidene-2-phenyloxazolinonesat 1561 cm−1 is a symmetric stretching mode associated with the —C=C—N=C— chain and that this feature has some C=N stretching character. The substitution experiments also show that the weak 1654 cm−1 Raman band has a high degree of C=C stretching character and may represent an essentially antisymmetric mode from the C=C—N=C moiety. The preresonance Raman excitation profiles show that the intensity enhancement follows an FB2 type dependence. The utility of the Raman spectrum as a probe for the chromophore responsible for the electronic transition in a highly conjugated system is discussed.

Preresonance Raman spectra and excitation profiles of some chemically and isotopically substituted trans-4-benzylideneoxazolin-5-ones

Resonance and preresonance Raman spectra of nine substituted trans-4-benzylidene- Δ2-oxazolin-5-ones are reported. The seven analogs with phenyl in the 2 position of the oxazolinone ring have either an electron donating or attracting group on one of the phenyl rings. Although shifts in λmax of up to 100 nm are observed the Raman spectra are very similar to that of the unsubstituted trans isomer. However, in the substituted compounds modes from the benzylidene portion may become weakly intensity enhanced. Replacing the 2-phenyl group by 2-methyl in the oxazolinone ring results in quite gross changes in the Raman spectrum. Substitution by 15N in the ring of a 2-methyloxazolinone reveals that a change in the vibrational coupling scheme occurs. Excitation profiles for the 2-phenyl and the 2-methyl analogs of 4-(p-nitrobenzylidene)oxazolinone indicate that in each compound ail intensity enhanced modes are coupled to the intense low energy absorption band near 350 nm and the intensity enhancement fits the FB2 terms of Albrecht and Hutley. However, differences in the relative intensity of the benzylidene nitro feature in the 2-methyl and 2-phenyl analogs, taken with the excitation profiles, suggest that in the 2-methyl compound the electronic transition responsible for Raman intensity enhancement is no longer primarily located in the C=C—N=C—Ph moiety.

Penetration of antitubercular drugs in clinical osteoarticular tubercular lesions

In 79 consecutive cases of skeletal tuberculosis the concentration of streptomycin and ethambutol was analysed. The material for analysis was obtained from the diseased joints of 14 patients and from cold abscesses from spinal or osseous lesions in 65 patients. The concentration of the drugs in the serum and in the tuberculous material was measured 3 hours after the systemic administration of the drugs in therapeutic doses. The concentration was expressed as microgram per ml of the tuberculous material and the data were subjected to statistical analysis. Streptomycin and ethambutol penetrated freely into the tuberculous joints; their concentration in the cold abscesses, however, was half to one third of the concentration in the serum. There was a wide range of concentrations; however, in the tuberculous joints as well as in the cold abscesses the concentrations were much higher than those considered to have an inhibitory effect on mycobacterium tuberculosis in clinical material.

Keratometric changes after cataract extraction

One hundred cases of uncomplicated cataract with clear corneae had cataract extraction and were examined at 20 days and six weeks after operation. Keratometry was done preoperatively and keratometry and retinoscopy at each of the follow-up visits. The study was undertaken to evaluate the type (whether pre- or postplaced) and the number of sutures (one, three, or five) that produce the least postoperative astigmatism. We found that the type of suture was immaterial but that three sutures produced the least astigmatism.

Resonance Raman studies in some carboni anhydrase-aromatic sulfonamide complexes

Resonance Raman spectra of 4-sulfonamido -4'-dimethylaminoazobenzene, 4-sulfonamido-4'-hydroxyazobenzene, and 4-sulfonamideo-4' aminoazobenzene bound to various isoenzymes of carbonic anhydrase were obtained by exciting into the sulfonamide absorption bands in the 400-500-nm region. In this way it was possible to obtain vibrational spectra of the sulfonamides in the active site unmasked by contributions from the vibrational modes of the protein and H2O solvent. Direct evidence was obtained for the presence of -SO2NH- in the complex, and it was possible to eliminate hydrophobic bonding and twisting in the Ph--N==N--Ph bonds as sources of the observed spectral changes. No detectable differences were found in the spectra of 4-sulfonamido-4'-dimethylaminoazobenzene bound to human carbonic anhydrase B and C or between these and the spectra of the sulfonamide bound to bovine carbonic anhydrase or Co(II) human carbonic anhydrase B. A new band appears in the spectra of the bound sulfonamides, and this is interpreted in terms of a change in geometry about the sulfonamido sulfur atom. A possible explanation for this change in geometry is that the bound sulfonamide group closely mimics the transition state of the reactants in the reversible hydration of CO2. Sulfonamide binding at pH 12.0 was not detected in the resonance Raman spectrum. Sulfonamide replacement of CN- in the binding site occurred over a period of minutes and could be monitored in the resonance Raman spectra.

A case of variegate porphyria in an Indian

A female patient aged 25 years developed abdominal and neurological symptoms followed by a photosensitive eruption during pregnancy. She was found to have variegate porphyria on investigation. Investigation of the family revealed on member having latent porphyria. To our knowledge, this is the first report of variegate porphytia from India.

Epidermolysis bullosa dystrophica et albo-papuloidea pasini in an Indian. A case report

A young lady with epidermolysis bullosa dystrophica et albo-papuloidea Pasini t(EBDAP) is reported. The diagnosis could be made through the clinico-morphological picture of albo-papuloid efflorescences (APE), their localisation on the trunk and extremities. The involvement of the nape of the neck, retro-auricular region, and scalp is also stressed. The efflorescences appeared 2–3 weeks after her birth, and bullae started developing at the sites subject to pressure just a few days after birth. The diagnosis was determined histopathologically. Oral corticotherapy was absolutely ineffective in improving APE, though it decreased the tendency to blister.

Thought stopping: a useful treatment in phobias of "internal stimuli"

Since Wolpe (1958) developed the idea of psychotherapy by reciprocal inhibition, systematic desensitization has emerged as an effective method of treatment in phobic states. There exists, however, a group of phobias which cannot be effectively treated with these techniques. These include fears of death, illness, harming other people, etc., and have been recognized by other authors as a separate group by themselves (Marks et al., 1969; Marks, 1969, 1970): phobias of internal stimuli. The search for a suitable method to treat these cases led us to use the thought stopping procedures described by Wolpe and Lazarus (1966, p. 132). There has been a notable lack of literature concerning this method, although Wolpe refers to J. A. Bain who used this technique in 1928.

Attitudes of mental hospital visitors towards unrestricted visiting

A programme was undertaken to study the attitudes of visitors to mental hospitals. Initially a series of individual non-directive tape-recorded interviews were conducted on a small sample of visitors, who freely discussed various topics, including staff attitude, visiting problems and difficulties in having a mentally ill relative. A provisional questionnaire was constructed from the significant points of the recorded interviews and was used on another sample of visitors in a pilot study, on the basis of which a final ‘multiple choice’ questionnaire was designed incorporating 28 items. Copies of the final questionnaire were then distributed from the wards of two mental hospitals to consecutive visitors, with a stamped envelope addressed to Nottingham University, informing them that the study was in connection with an independent survey. The distribution continued until few new visitors attended. Of the two hospitals, the first, The Pastures (Hospital A), serves a wide county catchment area and has an ‘unrestricted visiting hours' policy; the second, Kingsway (Hospital B), on the other hand, has a ‘limited visiting hours' policy and serves a compact urban catchment area. Altogether 510 questionnaires (75 per cent) were returned completed, 306 (8o per cent) for Hospital A and 204 (70 per cent) for Hospital B at the end of the study. The rest of the paper is confined to the analysis of these 510 questionnaires in relation to the question on the effect of unrestricted visiting, which has already been studied by Barton et al., from the nurses' point of view. The particular question asked by us was, 'some hospitals allow visitors to visit at any convenient time. What effect do you think this would have on (1) the patients, (2) the visitors, (3) the nursing staff, (4) the doctors?’ The replies were to be given on a five point scale for each question. The scale was ‘Very good-Good-No effect-Poor-Very poor.’ the graded adjectives being determined from the earlier tape-recordings.