[Anti-Bg(HL-A) antibodies].

The presence of specific anti-Bg hemaggluttinine in the sera of four patients, is shown. All our patients with anti-Bg antibodies had the antigen B27 on the HLA complex present. Anti-Bg antibodies were prooved by the Coombs technique.


[Epidemiology and etiology of acute leukoses in children].

In their work authors have analyzed some epidemiologic and etiologic data that can be taken as the elements of risk in leukemogenesis. The investigations have been done retrospectively in 212 children suffering from acute leukemia and treated in Pediatric Clinic in Beograd. Certain factors of risk are particularly studied as: repeated viral infections, repeated use of antibiotics, diagnostic and therapeutic irradiation of children, familiar data on congenital anomalies and cancer and same harmful prezygotic and prenatal influences of possible significance. The authors also presented the results of their cytogenetic investigations obtained from 32 children. It is especially pointed out the significance of detailed data taken from patients suffering from these diseases.


[Correlation between the frequency of HL-A antigens and antigens of the P system in the population of Serbia].

We studied the correlation between the antigens of the P system and the antigens and haplotypes of the HLA system in 334 nonrelated persons and 46 chosen families consisting of 166 members. On our material we found a distinct linear correlation between the antigens of the segregant serie A and especially of the segregant serie B and the P antigen of the blood groups. The correlation between the association of the antigens of series A and B and the antigens of the P system same as between the most frequent HLA haplotypes and the antigens of the P system, is also distinct. We described two cases of crossing over between the P and HLA system; the frequency of crossing over of 0,0435. We have confirmed the linkage between HLA and P and the likelihood that the genes are located on the same chromosome.


[Antibodies against HBs antigens as identified using the radioimmunologic method].

Antibodies to hepatitis Bs antigen identified only by radioimmunoassay, which is 8000 times more sensitive than counterelectrophoresis, were found in blood donors in 17%, in the Haemodialysis centre in 44%, in the patients of this centre in 47%. HBsAg and the antibodies have been tested in different series of albumin and gammaglobulin. Immunoglobulin anti HBs was prepared by the Blood transfusion centre in Ljubljana, and the Imunoloski zavod in Zagreb, and the problem of prevention, and production is discussed. Antigen-antibody complexes were prepared in vitro, and the results of the respective tests described.


[Prednisone therapy in patients with pernicious anemia (report of 2 cases)].

The effects of Prednisone therapy at two patients with pernicious anemia were studied on haematologic response, gastric secretion and gastric mucosal hystology. The treatment resulted in each case in correctin of the megaloblastic to normoblastic erythropoesis, and increse in reticulocytes, hemoglobin level and red cell count. Schilling-s test was normalised in one case that means that Prednison enchanced B12 absorption. Gastric secretion of acid and gastric hystology were not respond during the Prednisone therapy. It was discused about immunological problems in pernicious anemia which are very important and required continued investigations.


Tissue-specific esterases in the Xiphophorine fish Platypoecilus maculatus, Xiphophorus helleri, and their hybrid.

Tissue-specific esterases of the xiphophorine fishes Platypoecilus maculatus (platyfish), Xiphophorus helleri (swordtail), and their F1 hybrid have been analyzed using disc electrophoresis. Seven esterase zones (resolved into a maximum of nine bands) exist in these fishes, and these have been classified by employing specific inhibitors. Five of the seven zones, EST-1, EST-2, EST-5, EST-6, and EST-7, appeared to be carboxylesterases; while the two remaining zones, EST-3 and EST-4, were classified as cholinesterases. In the liver of the platfish, all seven esterase zones were detected, while the liver of the swordtail exhibited only five esterase zones. EST-1 and EST-3 were lacking in the liver tissue of the swordtail. All seven esterase loci were expressed in the liver tissue of the F1 hybrid. The reciprocal crosses gave the same results. In the fin, skin, skeletal muscle, and eye tissues from all three genotypes, three major esterase zones, EST-2, EST-5, and EST-7, were detected. In addition, EST-1 was frequently detected in all these tissues of the platfish and the F1, but was lacking in the swordtail. Serum from three genotypes showed one prominent esterase zone, EST-5; however, trace activity of EST-2 and EST-7 zones could also be detected. It seems that in all tissues of the F1 hybrid there is expression of all the esterase genes from the platfish. The results of the present study are discussed in the comparison to those from other studies on teleost esterases.


Biochemical characterization of six trisomics of grain sorghum, Sorghum bicolor (L.) Moench.

To determine protein differences of grain sorghum disomics and trisomics, we analyzed leaf extracts from six trisomics and a disomic control by disc gel, gel isoelectric focusing, and SDS gel electrophoresis. Based on the number and position of protein bands revealed by Coomassie blue staining, the disomic control could be differentiated from the trisomics, and trisomics could be shown to differ among themselves in most cases. SDS gel revealed the most protein bands, followed by isoelectric focusing and disc gel. However, disc gel electrophoresis was the simplest technique of the three and was just as effective in identifying trisomics and differentiating trisomics from the disomic control.


Bovine serum transferrin phenotypes AA, D1D1, D2D2, EE: their carbohydrate compositions and electrophoretic multiplicity.

Samples of homozygous bovine serum transferrins have been prepared and their purity has been ascertained by immunological techniques and electrophoretic analysis in SDS. Measurements of carbohydrate composition show that no significant differences exist among the phenotype variants AA, D1D1, D2D2, and EE. Chromatography of transferrin AA on DEAE-cellulose separated four subfractions, each of which corresponded well with one band obtained by polyacrylamide gel electrophoresis. Carbohydrate analyses of the individual subfractions did not show significant differences in sialic acid, hexose, or hexosamine contents. After desialylation with neuraminidase, each subfraction was converted to a major band and a minor band on gel electrophoresis. From the relative band positions of the desialylated transferrins, it was concluded that possession of sialyl residued by bovine transferrin is not the primary cause of electrophoretic multiplicity. Rather, sialic acid masks an underlying heterogeneity which most likely resides within the polypeptide chain. Further characterization of this heterogeneity will best be undertaken with the isolated asialotransferrin subfractions.


Genic homozygosity in an ancient reptile (Alligator mississippiensis).

Proteins assayed electrophoretically showed variation at only three of 49 presumed genetic loci in alligators from southwestern Louisiana. Average heterozygosity per individual was 0.021+/-0.012; proportion of polymorphic loci was 0.06. Data on the history, structure, and ecology of this alligator population are consistent with natural selection as the primary factor accounting for this low genetic variability. However, neither a historic population bottleneck nor some genetic mechanism limiting variability can be dismissed as a possible factor.


Characterization of electrophoretically cryptic variation in the alpine butterfly Colias meadii.

Enzyme polymorphism was characterized among the proteins of 14 loci of Coliae meadii by replicate electrophoresis in polyacrylamide gels of differing pore size. The results reveal a large number of variants, with a very skewed frequency distribution. A large fraction of the variants cannot be differentiated by electrophoresis in 5--7% acrylamide gels. This gel sieving approach permits an estimate of the relative contributions of charge and of conformation to electrophoretic mobility. Many of the variant proteins do not differ in charge. Most variants exhibit different degrees of interaction with the gel and presumably differ in conformation.


Membrane function in cystic fibrosis. I. Putrescine transport in normal and cystic fibrosis fibroblasts.

Putrescine transport was examined in normal and cystic fibrosis fibroblasts. No differences were observed in accumulation pattern, kinetics of uptake, or efflux between CF and normal cells. In both growing and growth-arrested CF and normal fibroblasts, exogenously supplied putrescine remained unchanged for at least 60 min. Some differences were observed in the response of CF and normal cells to environmental (media) changes.


Gene duplication in salmonid fishes: evidence for duplicated but catalytically equivalent A4 lactate dehydrogenases.

Skeletal muscle tissues from many species of salmonid fish are known to exhibit a set of three of five isozymes for A4-type lactate dehydrogenase (L-lactate: NAD oxidoreductase, E.C. 1.1.1.27), but the genetic basis for this isozyme system has not previously been assessed. This isozyme system was purified to homogeneity from salmon (Oncorhynchus tshawytscha) and shown to be composed of two polypeptides. Aalpha and Abeta, in binomial tetrameric combinations. Amino acid analysis revealed that Aalpha and Abeta are closely related but genetically distinct proteins, and thus are coded for the recently duplicated structural loci. Catalytic studies on the purified intact salmon isozyme system and on the isozymically pure Aalpha4 and Abeta4 homotetramers from brown trout (Salmo trutta) revealed no significant differences in catalytic properties among these enzymes, suggesting equivalent catalytic function of Aalpha and Abeta. These results, in combination with studies on polypeptide and isozyme ratios, suggest that one of the duplicated loci in salmon may be drifting toward a nonfunctional state by accumulation of mutations in regulatory DNA rather than in the structural gene itself.


Isoenzyme status and genetic variability of serum esterases in the lesser snow goose, Anser caerulescens caerulescens.

A maximum of 22 bands comprising four esterase subgroups--acetylesterase, carboxylesterase, cholinesterase, and acetylcholinesterase--were detected following electrophoresis of lesser snow goose sera on polyacrylamide gels. A minimum of seven structural genes was surmised to be involved in the biosynthesis of these enzymes following physiochemical characterizations. The genetic variability of these loci was calculated to be 1.25% average heterozygosity, while 14.3% of the loci were polymorphic. These estimates of genetic variability were substantially lower than those reported for other vertebrate species. The low degree of genetic variability found in snow goose serum esterases coupled with the extensive protein multiplicity observed may possibly reflect an adaptive strategy based on "biochemical plasticity" rather than genic heterozygosity for this species. The nature of evolutionary forces acting upon multiple enzyme systems such as esterases is discussed. The concept of "conditional neutrality" is introduced and defined within this context.


Glucose-6-phosphate dehydrogenase Porbandar: a new slow variant with slightly reduced activity in a South African family of Indian descent.

A new variant of the red cell enzyme glucose-6-phosphate dehydrogenase has been detected in a South African male of Indian descent and in several of his relatives. The enzyme variant is characterized by slow electrophoretic mobility, low Michaelis constants for the substrates glucose-6-phosphate and NADP, and increased utilization of the substrate analogues 2-deoxyglucose-6-phosphate and deamino-NADP relative to the normal (B+) enzyme. There is no evidence that the enzyme variant, for which the name "G6PD Porbandar" is suggested, is associated with any hematological abnormality.


The combining site of the dinitrophenyl-binding immunoglobulin A myeloma protein MOPC 315.

Magnetic-resonance techniques are used to refine the model of the combining site of the Fv fragment of the dinitrophenyl-binding mouse myeloma protein MOPC 315 constructed by Padlan, Davies, Pecht, Givol & Wright (1976) (Cold Spring Harbor Symp. Quant. Biol.41, in the press). Light-absorption studies indicate a dinitrophenyl-tryptophan interaction in the Fv fragment of the type occurring in free solution. The Dnp-aspartate-tryptophan complex is therefore used as a starting point for the n.m.r. (nuclear-magnetic-resonance) analysis of the dinitrophenyl-Fv fragment interaction. Ring-current calculations are used to determine the geometry of the complex. The specificity of complex-formation between dinitrophenyl and tryptophan is confirmed by the lack of ring-current shifts of the dinitrophenyl resonances when tryptophan is replaced by any other aromatic amino acid. Proton n.m.r. difference spectra (at 270MHz), resulting from the addition of a variety of haptens to the Fv fragment, show that the combining site is highly aromatic in nature. Calculations on the basis of ring-current shifts define the geometry of the combining site, which involves a dinitrophenyl ring in van der Waals contact with four aromatic amino acid residues on the protein. The observation of a nuclear Overhauser effect on the H((3)) resonance of the dinitrophenyl ring provides additional constraints on the relative geometry of the H((3)) proton and an aromatic amino acid residue on the Fv fragment. The specificity of the Fv fragment for dinitrophenyl ligands arises from a stacking interaction of the dinitrophenyl ring with tryptophan-93(L), in an ;aromatic box' of essentially tryptophan-93(L), phenylalanine-34(H) and tyrosine-34(L); asparagine-36(L) and tyrosine-34(L) also contribute by forming hydrogen bonds with the nitro groups on the dinitrophenyl ring. The n.m.r. results also confirm that the antibody-hapten reaction may be visualized as a single encounter step. An Appendix shows the method of calculation of ring currents for the four aromatic amino acids and their use in calculating structures.


Specificity of interactions of hapten side chains with the combining site of the myeloma protein MOPC 315.

The pKa values of the three histidine residues in the Fv fragment (variable region of the heavy and light chains) of the mouse myeloma protein MOPC 315, measured by high resolution n.m.r. (nuclear magnetic resonance), are 5.9, 6.9 and 8.2. The perturbation of the pKa of one of the histidines (pKa 6.9) on the addition of hapten and the narrow linewidth of its proton resonances suggests that it is at the edge of the combining site. References to the model of the Fv fragment [Padlan, Davies, Pecht, Givol & Wright (1976) Cold Spring Harbor Symp. Quant. Biol. 41, in the press] allows assignment of the three histidine residues, histidine-102H, histidine-97L and histidine-44L. The determination of the pKa of the phosphorus group, by 31P n.m.r., of a homologous series of Dnp- and Tnp- (di- and tri-nitrophenyl) haptens has located a positively charged residue. Molecular-model studies on the conformations of these haptens show that the residue is at the edge of the site. The model suggests that the positively charged residue is either arginine-95L or lysine-52H.


Characterization of double-stranded ribonucleic acid sequences present in the initial transcription products of rat liver chromatin.

At low ionic strength and with a low exogenous RNA polymerase/DNA ratio, rat liver chromatin directs the synthesis in vitro of RNA sequences rich in double-stranded segments. All the transcripts contain at least one double-stranded sequence. Most of the double-stranded segments are formed by intramolecular base-pairing of inverted complementary sequences separated by a single-stranded loop. They are heterogeneous in size, 35-45% of them being more than 80 nucleotides long. They contain 61-64% G+C, whether synthesized by rat liver RNA polymerase (form B) or Escherichia coli RNA polymerase. The largest double-stranded sequences are found in the largest transcripts, and are the most thermostable. The fidelity of base-matching is better in double-stranded transcripts synthesized on rat liver chromatin by homologous polymerase than in those synthesized on it by a bacterial polymerase, or in those synthesized by either of the two polymerases on pure DNA.


Purification and properties of histidinol dehydrogenases from psychrophilic, mesophilic and thermophilic bacilli.

As a first step in elucidating one molecular mechanism of adaptation to life at extreme temperatures, we purified and characterized the enzyme histidinol dehydrogenase (EC 1.1.1.23) from a number of bacilli whose growth temperatures range from 5 degrees t to 90 degrees C. The enzymes were purified by (NH4)2SO4 precipitation, ion-exchange chromatography on Sephadex, affinity chromatography on histamine- or histidine-Sepharose and preparative gradient gel electrophoresis. All had similar mol.wts. (29200), sedimentation coefficients (S20,w 2.56S), affinities for histidinol and NAD+ (Km = 48 micron and 0.2 mM respectively) and all had pH optima at 9.6. Marked differences were observed in stability with respect to temperature and the temperature at which the initial velocity for histidinol dehydrogenation was optimal. These optima range from 25 degrees C for the enzyme from the psychrophilic species through to 41 degrees C for the mesophiles to 85-92 degrees C for the extreme thermophiles. It is concluded that the ability of the enzymes to operate at their various optimum temperatures is an intrinsic property of their amino acid sequences.


N-phenylglycolhydroxamate production by the action of transketolase on nitrosobenzene.

The incubation of nitrosobenzene with yeast transketolase and D-xylulose 5-phosphate resulted in the production of N-phenylglycolhydroxamic acid. The addition of D-ribose 5-phosphate decreased the amount of hydroxamic acid that was produced. This conversion of nitrosobenzene into the glycollic acid-derived hydroxamic acid was shown to be an enzymic process, and a chemical mechanism for the conversion was proposed.


Substrate-induced deactivation of penicillinases. Studies of beta-lactamase I by hydrogen exchange.

The conformational motility of beta-lactamase I from Bacillus cereus was studied by hydrogen exhange. The time course of the isotopic replacement of peptide hydrogen atoms was followed by 'exchange-in' or 'exchange-out' experiments. Many of the substrates for this enzyme that have o-substituted aromatic or heterocyclic side chains (e.g. methicillin or cloxacillin) are known to effect a decrease in enzymic activity ('substrate-induced deactivation'). There was a marked discontinuity in the exchange-out curve when methicillin or cloxacillin was diffused into the enzyme solution. About one-half of the hydrogen atoms that were probed were affected by the presence of these substrates, and the change in the reactivity of the hydrogen atoms was also large. Substrates that do not bring about deactivation (benzylpenicillin and cephalosporin C) do not affect the hydrogen exchange, nor do reversible competitive inhibitors such as the penicilloic acid or penilloic acid. On the other hand, Zn2+ ions do affect the hydrogen exchange; their effect is similar to that of methicillin or cloxacillin.


Specificity of flavobacterial glycuronidases acting on disaccharides derived from glycosaminoglycans.

The specificity of the unusual flavobacterial glycuronidases that act on disaccharides containing delta4,5-unsaturated uronic acids was reinvestigated. The results show that the enzyme that hydrolyses the uronidic bond in disaccharides from hyaluronic acid and the chondroitin sulphates appears to be mainly specific for beta-D-(1 leads to 3)-derived linkages. The enzyme that hydrolyses the uronidic bond in a variety of disaccharides obtained from heparan sulphate and heparin appears to be specific for beta-D-(1 leads to 4)- and alpha-L-(1 leads to 4)- derived linkages. Thus the glycuronidases seem to be specific for linkage position rather than anomeric configuration, as had been thought previously. In addition, the data confirm other evidence that the major glucuronidic linkages in heparan sulphate and heparin have the beta-D-configuration, and the iduronidic linkages the alpha-L-configuration.


Acetyl-coenzyme A and coenzyme A analogues. Their effects on rat brain choline acetyltransferase.

Choline acetyltransferase has the same affinity for acetyl-CoA, propionyl-CoA and butyryl-CoA (Km=1.4 micron). Choline acetyltransferase may use the two latter compounds as substrate, but the longer the acyl chain the lower will be Vmax. CoA is an inhibitor (Ki=1.8 micron). The position of the 3'-phosphate is of primary importance. Desphospho-CoA is a weak inhibitor (Ki=500 micron). 5'-AMP is already an inhibitor (Ki=2500 micron). Phosphopantetheine is not an inhibitor. Dextran Blue is a potent inhibitor (Ki=0.05 micron). Choline acetyltransferase binds to hydrophobic affinity columns. Because of its affinity for nucleotides, affinity for Dextran Blue and hydrophobicity, it is proposed that it contains the 'nucleotide fold', which is a common structural domain present in several enzymes binding nucleotides.


Subtilisin modification of monodeamidated ribonuclease-A.

Limited proteolysis of RNAase-Aa(1) (monodeamidated ribonuclease-A) by subtilisin results in the formation of an active RNAase-S type of derivative, namely RNAase-Aa(1)S. RNAase-Aa(1)S was chromatographically distinct from RNAase-S, but exhibited very nearly the same enzymic activity, antigenic conformation and susceptibility to trypsin as did RNAase-S. Fractionation of RNAase-Aa(1)S by trichloroacetic acid yielded RNAase-Aa(1)S-protein and RNAase-Aa(1)S-peptide, both of which are inactive by themselves, but regenerate active RNAase-Aa(1)S' when mixed together. RNAase-Aa(1)S-peptide was identical with RNAase-S-peptide, whereas the protein part was distinct from that of RNAase-S-protein. Titration of RNAase-Aa(1)S-protein with S-peptide exhibited slight but noticeably weaker binding of the peptide to the deamidated S-protein as compared with that of native protein. Unlike the subtilisin digestion of RNAase-A, which gives nearly 100% conversion into RNAase-S, the digestion of RNAase-Aa(1) gives only a 50% conversion. The resistance of RNAase-Aa(1) to further subtilisin modification after 50% conversion is apparently due to the interaction of RNAase-Aa(1) with its subtilisin-modified product. RNAase-S was also found to undergo activity and structural changes in acidic solutions, similar to those of RNAase-A. The initial reaction product (RNAase-Sa(1)) isolated by chromatography was not homogeneous. Unlike the acid treatment of RNAase-A, which affected only the S-protein part, the acid treatment of RNAase-S affected both the S-protein and the S-peptide region of the molecule.


The structure of L-lactate oxidase from Mycobacterium smegmatis.

1. An improved purification was developed for L-lactate oxidase from Mycobacterium smegmatis. 2. The mol.wt. of the native enzyme by a sedimentation-equilibrium analysis was 345 000, and other ultracentrifuge methods gave values in the range 345 000-350 000. 3. An amino acid analysis, determinations of protein and flavin, a sedimentation-velocity analysis and an approach to equilibrium analysis gave values for the subunit mol.wt. in the range 43 500-47 000. 4. It was concluded that L-lactate oxidase contains eight subunits of mol.wt. 43 500. 5. Cross-linking of the subunits with dimethyl suberimidate and electron-microscopy studies were consistent with an octameric structure.


Modification of lactate oxidase with diethyl pyrocarbonate. Evidence for an active-site histidine residue.

1. Diethyl pyrocarbonate inactivated l-lactate oxidase from Mycobacterium smegmatis. 2. Two histidine residues underwent ethoxycarbonylation when the enzyme was treated with sufficient reagent to abolish more than 90% of the enzyme activity, but analyses of the inactivation showed that the modification of one histidine residue was sufficient to cause the loss of enzyme activity. The rates of enzyme inactivation and histidine modification were the same. 3. Substrate and competitive inhibitors decreased the maximum extent of inactivation to a 50% loss of enzyme activity and modification was decreased from 1.9 to 0.75-1.2 histidine residues modified/molecule of FMN. 4. Treatment of the enzyme with diethyl [(14)C]pyrocarbonate (labelled in the carbonyl groups) confirmed that only histidine residues were modified under the conditions used and that deacylation of the ethoxycarbonylhistidine residues by hydroxylamine was concomitant with the removal of the (14)C label and the re-activation of the enzyme. 5. No evidence was found for modification of tryptophan, tyrosine or cysteine residues, and no difference was detected between the conformation and subunit structure of the modified and native enzyme. 6. Modification of the enzyme with diethyl pyrocarbonate did not alter the following properties: the binding of competitive inhibitors, bisulphite and substrate or the chemical reduction of the flavin group to the semiquinone or fully reduced states. The normal reduction of the flavin by lactate was, however, abolished.


The high-performance liquid-chromatographic analysis of ficaprenol and dolichol.

A high-performance liquid-chromatographic method was devised which is capable of resolving the p-nitrobenzoyl derivatives of polyprenols containing 35-110 or more carbon atoms. This procedure was used for the determination of ficaprenol and pig liver dolichol composition and can be applied to mixtures of polyprenols as an analytical or preparative technique.


Partial purification of two lithocholic acid-binding proteins from rat liver 100 000g supernatants.

1. The partial purification of two lithocholic acid-binding proteins from liver 100 000g supernatants is described. 2. Gel-filtration, (NH4)2SO4 fractionation, Ca3(PO4)2 fractionation and ion-exchange chromatography were used. 3. Both proteins exhibited glutathione S-transferase activity; one may be the non-specific anion-binding protein ligandin. 4. Glutathione S-transferase activity of one of the binding proteins was inhibited by lithocholic acid.


The isolation and structure of C4, the fourth component of human complement.

The fourth component of complement, C4, was isolated from human serum in good yield, and in confirmation of previous reports was shown to be formed from three peptide chains, alpha, beta and gamma, with apparent mol.wts. 90 000, 80 000 and 30 000 respectively. Preparative methods are described for the isolation of the three peptide chains and their amino acid analyses reported. Component C4 contains 7.0% carbohydrate, alpha-chain 8.6% and the beta-chain 5.6%. The N-terminal amino acid sequences are given for 12 residues of the alpha-chain, eight of the beta-chain and 19 of the gamma-chain.


Accumulation of O6-methylguanine in non-target-tissue deoxyribonucleic acid during chronic administration of dimethylnitrosamine.

1. BD-IV rats were given labelled dimethylnitrosamine (2 mg/kg) by stomach tube on weekdays (Monday to Friday) for up to 24 weeks. The rats killed after 2, 4, 8, 16 and 24 weeks of treatment (72 h after the final dimethylnitrosamine gavage) and DNA was isolated from the pooled livers, kidneys and lungs. Purine bases were released from the DNA by mild acid hydrolysis and separated by Sephadex G-10 chromatography. 2. Throughout the experiment, the content of 7-methylguanine in liver DNA was approx. 16 times that in kidney and lung. The amount of this product increased in the DNA of all three tissues up to 16 weeks, but by 24 weeks had decreased by 20% in the liver and 46% in the other tissues. 3. O6-Methylguanine was not detected in liver DNA, but was easily measured in kidney and lung DNA after 4 weeks of dimethylnitrosamine administration. The amount of O6-methylguanine in kidney and lung DNA increased relative to that of 7-methylguanine, and by 24 weeks was 60% of the 7-methylguanine content in both tissues. 4. Incorporation of radioactive C1 breakdown products of dimethylnitrosamine into normal purines in DNA increased continuously in all three tissues. 5. The results are discussed with respect to the specific hepatocarcinogenic effect of chronic administration of dimethylnitrosamine and the possible contribution of increased DNA repair and DNA synthesis.


Purification and properties of a nuclear protein kinase from rat mammary gland.

A nuclear protein kinase that shows a high degree of substrate specificity for the phosphorylation of the acidic proteins casein, phosvitin and non-histone chromatin proteins, rather than the basic proteins histones and protamine, was partially purified from lactatingrat mammary gland. The enzyme is associated with the acidic protein fraction of chromatin. Nuclear kinase requires Co(2+) for activity, and other bivalent cations such as Mg(2+) and Mn(2+) can substitute partially for Co(2+). The kinase is further activates (2-3-fold) by various salts, their concentration for maximum stimulation being: NaCl, 150mm; KCl, 200mm; sodium acetate, 300mm. The sedimentation coefficient of the nuclear kinase is 8.9S and its mol.wt. is approx. 300000 by gel-exclusion chromatography. The enzyme is not activated by cyclic AMP or cyclic GMP and is inhibited neither by the regulatory subunit of mammary cyclic AMP-dependent protein kinase nor by the heat-stable protein kinase inhibitor from ox heart. Analysis of (32)P-labelled protein products reveals that the kinase transfers the terminal phosphate of ATP to serine and threonine residues of proteins. The enzyme, however, has specificity for the phosphorylation of threonine in casein and serine in phosvitin. Molecular size and enzymic characteristics of the nuclear protein kinase are clearly different from those of the cytosol enzyme previously characterized.


Semisynthetic analogues of insulin. The use of N-substituted derivatives of methionine as acid-stable protecting groups.

1. We describe the use of benzyloxycarbonylmethionine and ethoxycarbonylmethionine for the selective protection of the amino groups of glycine-A1 and lysine-B29 of pig insulin. We have used the Edman method to remove residues from the N-terminal and of the B-chain of the N(A1)N(B29)-di-protected derivatives. The benzyloxycarbonyl group shows slight but noticeable lability in the acid-cleavage step, but the ethoxycarbonyl group remained intact even after five cycles of degradation. 2. We have prepared the following truncated forms of insulin via the di(ethoxycarbonylmethionyl) derivative: des-Phe(B1)-insulin;des-(Phe(B1)-Val(B2))-insulin; des-(Phe(B1)-Val(B2)-Asn(B3))-insulin;des- (Phe(B1)-Val(B2)-Asn(B3)-Gln(B4))-insulin; des-(Phe(B1)-Val(B2)-Asn(B3) -Gln(B4)-His(B5))-insulin. 3. Insulin was re-synthesized from the di-protected des-Phe(B1)-insulin by reaction with an active ester of t-butoxycarbonyl-l-phenylalanine. The product after deprotection crystallized, and the immunoreactivity of the crystalline material was identical with that of the native protein. 4. We have prepared the following analogues of insulin in a similar manner: [l-Ala(B1)]insulin; [l-Val(B1)]insulin; [l-Tyr(B1)]insulin; [m-F-l-Phe(B1)]insulin; [o-F-l-Phe(B1)]-insulin; [o-F-l-Phe(B2)]des-Phe(B1)-insulin. All had between 34 and 62% of the activity of insulin in the fat-cell test. 5. We have also investigated the use of the benzyol, toluene-p-sulphonyl, p-nitrobenzyloxycarbonyl and 2,4-dinitrophenyl groups for the N-protection of the methionine active esters. Each should have had some particular advantage over the benzyloxycarbonyl and ethoxycarbonyl groups, but all proved in practice to have disadvantages that more than outweighed anything in their favour.


A simplified electrophoretic system for determining molecular weights of proteins.

Electrophoresis of 31 different proteins in commercially prepared polyacrylamide gradient gels, Gradipore, yields a linear relationship between a hypothetical limiting pore size (the reciprocal of a limiting gel concentration, GL) and the cube root of the mol.wt., over the range 13 500-9000 000. A regression analysis of these data reveals that 98.6% of all variability in 1/GL is explained by the molecular weight, and this degree of accuracy compares favourably with existing methods for the determination of molecular weight by retardation of mobility in polyacrylamide. This new procedure has the additional advantages that molecular-weight standards can be obtained from readily available body fluids or tissue extracts by localizing enzymes and other proteins by standard histochemical methods, and that the same electrophoretic system can be used in determining molecular weights as is used in routine surveys of populations for individual and species variation in protein heterogeneity.


Characterization of glyoxalase I purified from pig erythrocytes by affinity chromatography.

Glyoxalase I (EC 4.4.1.5) was purified about 10000-fold from pig erythrocytes in a yield of approx. 20%. The purification included affinity chromatography on S-hexylglutathione coupled to Sepharose 4B. The purified enzyme normally contained two catalytically active components which were resolved by polyacrylamide-gel electrophoresis. After treatment with reduced glutathione only one component was found. The two components were also demonstrable after isoelectric focusing or DEAE-cellulose chromatography and could also in these cases be fused into one species by preincubation with reduced glutathione. It is proposed that the most acidic form of glyoxalase I is a mixed disulphide with glutathione. Except for these interconvertible forms, the purified enzyme was homogeneous, as judged by disc electrophoresis and sodium dodecyl sulphate/polyacrylamidegel electrophoresis. The molecule is a dimer (48000 daltons), composed of apparently identical subunits (24000 daltons). The isoelectric point was 4.8 at 4 degrees C. The amino acid composition was consistent with the low isoelectric point. The enzyme contained about two thiol groups per enzyme molecule. EDTA inactivated the enzyme and bivalent metal ions could restore fully or partially the catalytic activity; Mg(2+) and Mn(2+) gave highest activity. It is proposed that a major biological function of glyoxalase I is the detoxification of methylglyoxal formed by enterobacteria in the alimentary canal.


Purification and properties of a ribosomal casein kinase from rabbit reticulocytes.

A casein kinase was isolated and purifed from rabbit reticulocytes. About 90% of the enzyme activity co-sedimented with the ribosomal fraction, whereas about 10% of the enzyme activity was found in the ribosome-free supernatant. Both casein kinases (the ribosome-bound enzyme as well as the free enzyme) showed identical activity and the same molecular weight. On sodium dodecyl sulphate/polyacrylamide-gel electrophoresis a single band of about 70 000 mol.wt. was observed. Sucrose-gradient analysis, however, showed that the enzyme activity sedimented with a s20,w of approx. 7.5S. This observation suggested that the casein kinase is a dimer composed of subunits of identical molecular weight. The enzyme utilizes GTP as well as ATP as a phosphoryl donor. It preferentially phosphorylates acidic proteins, in particular the model substrates casein and phosvitin. Casein kinase is cyclic AMP-indepenoent. The Km values for ATP and GTP with phosvitin as a substrate were determined as 1.2 and 8.8 micrometer respectively.


Effect of lipophilic character on the biological activity of synthetic angiotensin peptides.

[Ile5]angiotensin II (angiotensin) derivatives bearing acetyl, propionyl, butyryl, pentanoyl or hexanoyl moieties at the N-terminal amino group were synthesized. The myotropic effects in vitro (on guinea-pig ileum and rat uterus) of desamino-angiotensin and of the above compounds did not correlate with their partition coefficients in butan-1-ol/acetic acid/water. The pressor effects in vivo in rats showed a negative correlation with the partition coefficients, discouraging further attempts to raise the pressor potency of angiotensin analogues by increasing their hydrophobicity. The half-times for onset and reversal of the biological responses also did not correlate with partition coefficients, but reversal was retarded by the presence of a free amino group. It is concluded that partition between aqueous medium and the lipophilic receptor environment is not a limiting factor for angiotensin activity.


A novel mechanism of enzymic ester hydrolysis. Inversion of configuration and carbon-oxygen bond cleavage by secondary alkylsulphohydrolases from detergent-degrading micro-organisms.

The hydrolysis was studied of potassium (+)-octan-2-yl sulphate by two analogous, optically stereospecific, secondary alkylsulphohydrolases purified from two detergent-degrading micro-organisms, Comamonas terrigena and Pseudomonas C12B. Polarimetry studies have shown that (+)-octan-2-yl sulphate prepared from (+)-octan-2-ol is hydrolysed by both enzymes to yield (-)-octan-2-ol. This inversion of configuration implies that the enzymes are catalysing the scission of the C-O bond of the C-O-S linkage, a type of bond scission apparently not hitherto encountered among hydrolytic enzymes acting on ester bonds. Enzymic hydrolysis of potassium (+)-octan-2-yl sulphate in the presence of H218O and analysis of hydrolysis products for the presence of 18O has confirmed that C-O bond scission (and not O-S bond scission) occurs with both enzymes.


Carbon-2 proton exchange at histidine-41 in bovine erythrocyte superoxide dismutase.

The C-2 proton of one histidine residue in bovine erythrocyte superoxide dismutase is shown to be particularly labile. This residue is identified by tritiation, protein digestion and subsequent peptide 'mapping' as histidine-41. A half-life for the exchange of histidine C-2 1H for 2H in 2H2O as solvent, at pD 8.1 and 40 degrees C, is estimated as approx. 9.2h, by 1H nuclear-magnetic-resonance spectroscopy.


Lymphocyte activation in rheumatoid synovial effusion.

A rapid method based upon increase in intranuclear birefringence occurring in early stages of lymphocyte activation was used to examine whether there is any difference in lymphocyte activation between lymphocytes from synovial fluid and those from peripheral blood in patients with rheumatoid arthritis and other joint diseases. Increased activation of synovial fluid lymphocytes compared with peripheral blood lymphocytes was seen only in synovial effusions obtained from patients with rheumatoid arthritis.


Radioimmunoassay of serum myoglobin in polymyositis and other conditions.

Radioimmunoassay of serum myoglobin was done in 53 patients with polymyositis syndromes and other conditions. Serum myoglobin values in 33 healthy subjects ranged from 4 to 77 [mean 33.3 +/- 19.8 (SD)] ng/ml. Fifty percent of polymyositis patients had elevated serum myoglobin levels (greater than 80 ng/ml). Serum myoglobin values in polymyositis patients fluctuated more sensitively than CPK and GOT. Combined estimation of myoglobin and CPK offers advantages for the detection of muscle injury and the prediction of disease exacerbation.


Severe systemic lupus erythematosus with nephritis in a boy with deficiency of the fourth component of complement.

A young boy with severe systemic lupus erythematosus was found to be totally deficient in the fourth component of complement. Family studies were consistent with an autosomal recessive mode of transmission and with linkage of the gene(s) determining C4 deficiency to the major histocompatibility complex; no disease states were associated with heterozygosity. This patient has had severe multisystem disease and immune complex glomerulonephritis presumably the alternative pathway of complement was utilized in the pathogenesis of his nephritis.


Localizing of C-reactive protein in synovium of patients with rheumatoid arthritis.

Synovial biopsies from 8 patients with rheumatoid arthritis, 2 patients with degenerative osteoarthritis, and 4 patients with nonarthritic disease were studied for localization of C-reactive protein (CRP) using immunofluorescence microscopy. The nuclei of many synoviocytes and histiocytes in rheumatoid synovial membrane were found to bind CRP. Cultures of rheumatoid synovium in 14C-labeled amino acids produced radioactive IgG, IgM, IgA, and C3; but not CRP, indicating the synovial-bound CRP was not of local origin. A few CRP-binding nuclei were present in one osteoarthritis synovium, but none was found in the other and none in synovium from the 4 nonarthritis patients. The nature of the nuclear CRP ligand in rheumatoid synovium was not determined.


Adsorption of polymorphonuclear leukocyte lysosomal enzymes to monosodium urate crystals.

Monosodium urate (MSU) crystals induced prompt release of lysozyme, and slower release of beta-glucuronidase, alpha-mannosidase, and lactic dehydrogenase (LDH) from polymorphonuclear leukocytes. At increasing crystal concentrations, an increasing delay in the apparent onset of beta-glucuronidase release was detected which appears to be due to selective absorption of enzyme activities to the MSU crystals: beta-glucuronidase greater than LDH greater than alpha-mannosidase greater than lysozyme. Lysosomal enzyme adsorption by MSU crystals may then contribute to experimental error or may modulate gouty inflammation.


Destruction of joint homografts. An experimental study.

The host synovium undergoes a striking transformation at about 26 weeks after joint homografting. Histologically the synovium invaded and destroyed the graft with which it came in contact, becoming markedly hypercellular; the infiltrate consisted mainly of plasma cells and lymphocytes. The synovium at this stage closely resembled a rheumatoid pannus. The cartilage in contact with this invasive synovium lost its staining qualities, failed to take up S-35, and was gradually destroyed. The mechanism causing this transformation remains unclear. It is postulated that these changes could be due to an inflammatory or immune response.


Acute bilateral symmetrical pathologic fractures of the lateral tibial plateaus in a patient with Gaucher's disease.

A 41-year-old woman with Gaucher's disease developed bone crises of both proximal tibiae and of her spine concurrent with a syndrome of severe gastroenteritis. Three to six months later the bilateral symmetrical pathologic collapse of both lateral tibial plateaus occurred. The unusual occurrence of multiple bone crises with the gastroenteritis suggests a common causative agent, possibly a severe viremia.


Synovectomy and total joint arthroplasty for recurrent hemarthroses in the arthropathic joint in hemophilia.

Severe hemophiliacs with intractable bleeding into one or more joints despite adequate clotting factor replacement therapy are difficult management problems. Synovectomy has controlled bleeding only in joints without significant arthritis destruction. Total joint replacements have been performed in arthropathic joints, but not when uncontrolled bleeding was a concurrent problem. This report describes a hemophiliac with uncontrolled bleeding into an arthritic knee who was successfully managed by combining synvectomy with total knee replacement.


Allopurinol hepatotoxicity. Case report and literature review.

Significant hepatotoxicity due to allopurinol seems to be rare. Only 6 such cases have been recorded in the literature. The clinical and histopathologic findings of allopurinol-induced liver injury are variable in the previously reported cases. Described herein is another patient with allopurinol hepatotoxicity. Of interest is the similar histopathology between the present case and the two previously reported cases of allopurinol-induced granulomatous hepatitis; thus this is the third such recorded case. Allopurinol should be suspected when liver abnormalities occur following use of this drug.


[Treatment of carotid-cavernous fistula with the Serbinenko balloon catheter].

After a critical survey of the methods of treating carotid-cavernosus fistulae employed until now and some special techniques, the endovasal method using the flow-in catheter with droppable microinflator after Serbinenko is described. In this technique, a latex inflator is filled intracavitarily with cold-vulcanized silicon rubber by the transcutaneous-transcarotidal route and left in situ for a selective closure of the fistula. 3 cases treated by the author with late results show the advantages of the method by which the carotid can be reconstructed.


[Problem of the special pathology of brain tumors].

The post-mortem material of the Erfurt Pathological Institute covering the period from 1953 to 1975 included 1376 primary tumours of the central nervous system, which corresponds to 2.6 per cent of all autopsies and 9.6 per cent of the autospies for malignant tumours. Thus, tumours of the central nervous system show the same frequency as leukoses and lymphomas and tumours of the female genitals and range before the tumours of the colon. The age distribution confirms well known conditions, but shows as apecu liarity that in infancy cerebral tumours occur just as frequently as in childhood and that the frequency of the occurrence of meningiomas before and after the 60th year of life is practically the same; but after that time they are clinically diagnosed in a distinctly less frequent number. Wrong clinical diagnoses were made in 23.5 per cent of the observations. Finally, it is pointed out that the intraoperative picture of the tumours may be misleading and only histological examinations will be helpful.


[Problems in the general pathology of brain tumors].

The various classifications of tumours of the central nervous system employed at present are analysed. A generally accepted classification is still missing. In any case, one should avoid to place cerebral tumours outside the systems, or even to exclude them from the considerations of general oncology. A solution to the problem requires as far as possible a complete detection of all cerebral tumours by autopsy. In particular, patients who were not opperated can on furnish essential indications. Even histologically and clinically so important indications with regard to dignity and malignity cannot be obtained with absolute certainty. For the greater part of cerebral tumours, degrees of malignity ("grading") cannot be established with sufficient reliability. In the GDR tumour statistics, cerebral tumours are almost as frequent as leukoses or the so-called lymphomas.


[Experiences from the conception of a complex-diagnostic neuroradiologic department integrated into a neurosurgical clinic (model of a novel functional and structural solution)].

For planning and designing the reconstruction of an superannuated radiological department of a neurosurgical supra-regional hospital the following requirements had to be taken into account: 1. Complex-diagnostic working style of a neuroradiological department integrated in the hospital complex. 2. Ensuring of a comprehensive operative-technical examination programme by appropriately equipped work places. 3. The aim to improve the working conditions of the personnel and the medical care of the population. The ideal solution was achieved by an extension of the neurosurgical clinic in the form of a diagnostic tract comprising neurosurgical O.P.D. and an after-care department, electro-diagnostic and neuroradiological departments. In the centre of the novel solution there is the function tract of the neuraradiological department in which the complex building method enables a clear division into main zones (patients zone, function zone, personnel zone). It ensures economical working for the benefit of both patients and personnel. Charts showing the sequence of operations and graphic representations of the constructional solution as well as recommendations for equipment standards for the work places illustrate the project, which is certainly suitable for serving as an internation model of similar special establishments of public health services.


[Possibilities for error in the diagnosis of craniopharyngiomas].

Age of affection, preferential seat, clinical picture and instrumental diagnosis of craniopharyngiomas are discussed on the basis of 30 observations. Although childhood and adolescence are the leading age groups, there also was a 64-year-old patient. Three courses of the disease were selected: a 6-year-old girl presented both clinically and by instrumental examination indications of a cerebellar tumour; a mandarin-sized arachnoid cyst near the midline was removed. One year later, a suprasellar craniopharyngioma of the size of a chestnut was removed  subtotally. Retrospectively, the arachnoid cyst was only seen as a side-finding. A 13-year-old girl showed angiographically and in the pneumoencephalogram signs of a cerebellar tumour located in the middle; the operation showed regular conditions. Only frontal trepanation showed a plum-sized cystic retrochiasmal craniopharyngioma. Similar conditions were found in another 6-year-old girl.


[Rare traction injury to the radial nerve].

Presenting 3 examples, the author deals with the traction damage of the N. radialis in which the lesion was located in the region of the elbow. In each case, the injury of the nerve was caused by a violent hyperflexion of the wrist when the back of the hand was struck by a heavy blow. The symptoms were produced immediately after the trauma. Complete recovery was achieved in all patients after a few weeks.


[1st experience with laser beams in the treatment of neurosurgical diseases].

The Sharplan 791 type CO2-laser, specially adapted to neurosurgical requirements, was used in the surgery of 9 gliomas, 10 meningeomas, 6 patients presenting metastasis, 1 case of vascular malformation, intracranial interventions, 1 case of hippocampectomy, 2 cases of neurinomas, 2 intramedullar tumours of the spinal cord, 1 case of thoracic commissurotomy, 1 case of thoracic prolaps of intravertebral disc, 1 case of vertebral metastasis and in 3 cases of stump neurinoma. Detrimental effects on the patients as well as any hazards to the surgical staff have not been observed. The cutting effect was mainly used for the incision of soft part, in some cases also for the formation of bony cover. Moreover the CO2-laser beam was used for coagulation and vaporisation. Particular advantages are offered by the equipment when working under the surgical microscope. Topografic precision and energetic dosing make the equipment a valuable supplement of the surgical instruments, available until now.


[Serum immunoglobulin (IgG, IgM, IgA) levels in patients with primary brain tumors (author's transl)].

The concentration of serum immunoglobulins (IgG, IgM, IgA) in 63 patients of primary brain tumors were determined by the method of single radial immunodiffusion. 1) The mean values and standard deviations of three major serum immunoglobulins in 18 cases of meningioma were as follows; IgG, 1297.0 +/- 387.9 mg/dl, IgM, 165.1 +/- 153.4 mg/dl, IgA, 219.5 +/- 76.7 mg/dl. These values were not significantly different with those in normals. 2) 45 cases of gliomas showed; IgG, 1190.5 +/- 378.3 mg/dl, IgM, 160.0 +/- 75.9 mg/dl, IgA, 189.8 +/- 91.5 mg/dl. These values were in normal levels as compared with normal serum immunoglobulins. 3) Values of serum immunoglobulins in 19 cases of glioblastoma multiforme were compared with those in 18 cases of astrocytoma to know the relationship between histological malignancy and levels of serum immunoglubulins. But no significant difference was observed between these values. The levels of three major serum immunoglobulins either in meningiomas or in gliomas were not significantly different with those in normals. Therefore, the levels of serum immunoglobulins could not be used as a diagnotic procedure in cases of primary brain tumors.


[Follow-up results of microsurgery of intracranial aneurysms (author's transl)].

In the past 7 years, 403 cases of intracranial aneurysms were submitted to microsurgical operations. The operative mortality was 5.4%, and in the follow-up, 82.4% are working, 6.2% are caring for self and 5.9% are either bed-ridden or dead from other causes after discharge. If 6 cases of Grade V are excluded from the statistics and the day of subarachnoid hemorrhage (SAH) is counted as the 1st day, cases submitted to microsurgery on the 1st, the 2nd and the 3rd days showed no mortality and 72.7% of them are working in the follow-up. Cases undergone micro-surgery on the 4th through the 8th day showed a high mortality of 15.2% due to postoperative vasospasm, whereas in cases submitted to micro-surgery in the 2nd week after SAH the operative mortality was 6% and in cases submitted to micro-surgery later than the 2nd week it was 3%. In the follow-up 84% and 85.6% are working in the latter two respectively. These results seem to encourage ultra-early surgery for ruptured aneurysm cases. However, one should always bear in mind that the acute stage of SAH should be regarded as a "systemic disease", not as a "local disease", and only those who have ability and facility to manage this systemic disease may be qualified to perform early surgery for ruptured aneurysms.


Laryngeal incompetence during experimental "relative analgesia" using 50% nitrous oxide in oxygen. A preliminary report.

Ten healthy adult volunteers inhaled 50% nitrous oxide in oxygen while dental treatment was simulated for a period of 30 min. During this time 15 ml of radio-opaque dye was placed at the back of the tongue. A similar control study was performed 1 week later, the subjects inhaling pure oxygen without nitrous oxide. X-ray examination revealed that two of the 10 volunteers had aspirated dye while breathing nitrous oxide and oxygen, but no aspiration was apparent in the control study.


Right versus left lateral tilt for Caesarean section.

In 60 mothers with normal placental function, the relative merits of right and left lateral tilt during Caesarean section were assessed. Maternal-foetal biochemical values and relationships were generally more satisfactory with the left lateral position. The incidence of hypotension (revealed aorto-caval occlusion) before and after induction of anaesthesia, was significantly greater (P less than 0.001) with the "right side down" posture.


Placental transmission of atropine at full-term pregnancy.

Measurements of placental transmission of atropine were performed during Caesarean section. Twenty-five patients received 3H-atropine 0.5 microgram . kg-1 i.v. 1-30 min before delivery. Maternal venous blood was sampled before the induction of anaesthesia and at the moment of delivery, together with umbilical arterial and venous blood. Total hydrogen-3 activity was determined by liquid scintillation counting. The stability of 3H-atropine was confirmed by paper chromatography. The concentrations in the umbilical vein 1 and 5 min after injection were respectively 12% and 93% of the corresponding maternal value. Those in the umbilical artery were approximately 50% of those in the umbilical vein during the same period.


Blood volume replacement in acute anaphylactic cardiovascular collapse related to anaesthesia.

In seven patients who suffered anaphylactic cardiovascular collapse during anaesthesia the degree of haemoconcentration was used to assess changes in blood volume. The patients who were resuscitated with electrolyte solutions, or electrolyte solutions with a small volume of colloid, showed haemoconcentration suggesting plasma loss of 20.2-37%. Patients who were resuscitated initially with colloid solutions showed minimal haemoconcentration. In anaphylactic cardiovascular collapse, the reduction of blood volume is a result of loss of plasma and colloid solutions should be used to replace the volume deficit.


Spread of extradural analgesia following caudal injection in children. A statistical study.

Data on the segmental spread of analgesia from three independent studies of caudal extradural blocks in children with three different local anaesthetic agents were examined with multiple regression techniques to find the effects of age on dose requirements. All three studies confirmed the existence of a linear relationship between the spread of analgesia and age. As there were no significant differences between the three regression lines a common regression line was calculated. This may be used as a guideline for predicting dose requirements in the daily routine of anaesthesia. By injecting a mixture of a radio-opaque substance and 4% lignocaine it was shown by comparison of the radiological spread of the solution and the distribution of clinical analgesia that the latter always exceeded the former by four to six segments. This may indicate the occurrence of diffusion.


A prospective study of hepatocellular function after repeated exposures to halothane or enflurane in women undergoing radium therapy for cervical cancer.

Ninety-nine Black females receiving radium therapy for carcinoma of the cervix uteri under either halothane (50 patients) or enflurane (49 patients) anaesthesia were studied. Thirty-six received a second and 13 a third exposure to halothane or enflurane. There were no significant changes from the control values in the serum concentrations of aspartate aminotransferase (s.g.o.t.), gamma glutamyl transpeptidase (gammaGT), lactic dehydrogenase (SLD), alkaline phosphatase (SAP) and proteins. Total serum bilirubin (TSB) decreased significantly during the first exposure to enflurane (P less than 0.01). This trend was reversed with subsequent anaesthetics in both the halothane and enflurane groups.


Suxamethonium pains and electromyograph recordings in children.

Surface electromyography was used to investigate muscle activity in children following the administration of suxamethonium. The duration, amplitude and frequency of muscle action potentials recorded in children were similar to those in adults. Twenty-three children had muscle action potential frequencies in excess of 50 Hz, but only two suffered pain after operation. The relationship between high frequency discharge rates of motor units noted in adults in earlier studies does not apply to children.


Use of neostigmine after snake bite.

Cobra venom consists of a neurotoxin which is responsible for respiratory paralysis simulating that associated with a non-depolarizing muscle relaxant. A combination of artificial respiration and neostigmine has been useful in resuscitating a child bitten by a snake.


Depression of hypoxic ventilatory response by halothane, enflurane and isoflurane in dogs.

The ventilatory responses to isocapnic hypoxia and hypercapnia were studied in six dogs each with a tracheostomy, awake and during anaesthesia with halothane, enflurane and isoflurane (1-2.5 MAC). Isocapnic hypoxic ventilatory response (HVR) was expressed as the parameter A, such that the greater the value of A, the greater the hypoxic response. In the anaesthetized dogs HVR (A) was reduced significantly from the awake value of 2010 +/- 172 (mean + SEM) to 630 +/- 173 by 1 MAC halothane, 495 +/- 105 by 1 MAC enflurane and 952 +/- 157 by 1 MAC isoflurane (PL0.05). All three anaesthetic agents produced significant depression of HUR at 1 MAC, but enflurane was more depressant than isoflurane. At 1.5 MAC all three anaesthetics produced equal and significant depression of HVR at equianalgesic concentrations. Further increases in anaesthetic concentration caused no increase in depression. Hypercapnic drive, as measured by the slope of the VE/PACO2 response curve, was reduced significantly from 9.75 litre min-1 kPa-1 +/- 2.4 in awake dogs to 0.83 +/- 0.56 after 1 MAC halothane, 0.68 +/- 0.53 after 1 MAC enflurane and 1.58 +/- 0.75 after 1 MAC isoflurane. In addition, hypercapnia-induced augmentation of the hypoxic drive was abolished by 1 MAC halothane or enflurane and diminished markedly by 1 MAC isoflurane. It may be clinically significant that hypoxia and hypercapnia during anaesthesia with these agents did not produce optimal stimulation of ventilation.


Calcium and magnesium contents of malignant hyperpyrexia-susceptible human muscle.

The calcium and magnesium contents of muscle obtained by muscle biopsy of patients referred for malignant hyperpyrexia screening were determined. The susceptibility to malignant hyperpyrexia was made on the basis of the halothane contracture test. No difference in cation concentrations was found between the normal and malignant hyperpyrexia-susceptible groups.


Effects of morphine and ketamine anaesthesia and surgery on plasma concentrations of luteinizing hormone, testosterone and cortisol in man.

Thirty patients received morphine and 27 received ketamine. Morphine anaesthesia did not influence plasma concentrations of luteinizing hormone (LH) significantly, but there was a significant increase during ketamine anaesthesia. Plasma LH increased in the early stage of surgery under both anaesthetics. A significant decrease in the plasma concentration of testosterone was found during and following both techniques of anaesthesia, the lowest concentration being detected on the first day after surgery. Ketamine anaesthesia, but not morphine, stimulated adrenocortical function significantly. Furhter stimulation was detected in the periods during and after operation with both anaesthetic techniques.


Anaesthetic management of patients with phaeochromocytoma. A review of 102 cases.

A total of 102 patients with phaeochromocytoma who underwent surgery by the same team between 1964 and 1976 were allocated to three groups according to the anaesthetic protocol used: (1) balanced anaesthesia and control of hypotension with noradrenaline; (2) anaesthesia with halothane and replacement of blood volume; (3) neuroleptanalgesia (droperidol and phenoperidine) and replacement of blood volume. None of the patients in any of the three groups received adrenergic inhibitors before anaesthesia. Comparison of the results in the three groups revealed that the major factor responsible for reduction of operative mortality to almost zero was control of hypotension by replacement of blood volume rather than by the use of noradrenaline following resection of the tumour, whereas the type of anaesthetic agent used was of secondary importance.


Respiratory effects of extradural analgesia after lower abdominal surgery.

Blood-gas tensions, FRC and volume of trapped gas (VTG) in the lung were measured in patients on the day before lower abdominal gynaecological surgery, and twice on the day following surgery, before and after establishing lumbar extradural block (EDB) using 0.5% bupivacaine to provide analgesia after operation. FRC and VTG were measured with the closed-circuit helium-dilution technique. Mean VTG was 175 ml before operation and 275 ml after operation. PaO2 decreased significantly after operation, and the changes in FRC and VTG that occurred were related qualitatively. EDB did not significantly alter FRC, VTG or PaO2. Individual changes in FRC could not be related to changes in VTG or PaO2. Although EDB provided effective analgesia, the variables measured did not indicate that EDB conferred an immediate respiratory advantage.


Early and late radiation reactions in mouse feet.

The relationship between early and late radiation damage has been analysed by comparing the early skin reaction (desquamation in the first month) with the late foot deformity seen at 6 months, for mice from a wide variety of different fractionation experiments. A close correlation was observed between the early and late reactions in each experiment and the relationship was the same for all the experiments except for 17-64 fractions given over a short time. The fractionation schemes included single doses and 2-64 fractions, and the overall times ranged from 1 day to 6 months. This close correlation for such a wide variety of treatments suggests that the two end points are not necessarily independent responses of different tissues and that late damage in the mouse foot can result secondarily from depletion of the basal layer of the epidermis. Late foot deformity is therefore not a reliable model for the response of a slowly proliferating tissue.


Tumour volume response, initial cell kill and cellular repopulation in B16 melanoma treated with cyclophosphamide and 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea.

The relationship between tumour volume response and cell kill in B16 melanoma following treatment in vivo with cyclophosphamide (CY) and 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea (CCNU) was investigated. Tumour volume response, expressed as growth delay, was estimated from measurements of tumour dimensions. Depression of in vitro colony-forming ability of cells from treated tumours was used as the measure of tumour cell kill. The relationship between these parameters was clearly different for the two agents studied. CY produced more growth delay (7.5 days) per decade of tumour cell kill than CCNU (2 to 3.5 days). The possibility that this was due to a technical artefact was rejected in favour of an alternative explanation that different rates of cellular repopulation in tumours treated with CY and CCNU might be responsible. Cellular repopulation was measured directly, by performing cell-survival assays at various times after treatment with doses of CY and CCNU which produced about 3 decades of cell kill. The rate of repopulation by clonogenic cells was much slower after treatment with CY than with CCNU, and this appears to account for the longer duration of the growth delay obtained with CY.


Alterations of mononuclear phagocyte function induced by Lewis lung carcinoma in C57BL mice.

The function of the reticulo-endothelial system in mice bearing Lewis lung carcinomas has been measured by(1) the rate of clearance of carbon particles from the circulation in vivo and calculation of the phagocytic index K; (2) chemotactic locomotion of macrophages in vitro in the presence or absence of serum or tumour supernate. The ability of the bone marrow to develop macrophage colonies in vitro in the presence or absence of sera from tumour-bearing mice has also been tested. A clear depression of macrophage locomotion and macrophage colony formation in vitro was found in the presence of sera or tumour supernates from tumour-bearing mice as early as 24 to 72 h after tumour inoculation. Similarly, tumour-bearing mice showed marked depression of carbon clearance in tests repeated throughout the first 72 h after tumour inoculation. This early depression of macrophage function may be an important step in allowing escape of tumour cells from host resistance.


Follow-up studies on the immune status of patients with Hodgkin's disease after splenectomy and treatment, in relapse and remission.

Sixty-two patients with Hodgkin's disease have been followed for one year from the start of treatment. Immunological assessments were repeated after intensive treatment, in patients relapsing and in those in remission at one year. In patients achieving remission, overall cellular immunity, after deteriorating with therapy, particularly cytotoxic chemotherapy, returned to pre-treatment levels in remission when there was little evidence of cellular immune disturbance. Serum IgG and IgM levels fell with intensive chemotherapy in splenectomized patients. IgA and IgM levels were lower (irrespective of splenectomy or therapy status) in remission than at presentation or after treatment. Relapse or non-response was usually associated with deteriorating cellular immunity. Herpes zoster/varicella and candida infections (seen in 6 patients) were preceded by, or associated with, deterioration of cellular immunity.


Second primary cancers in patients with tumours of the salivary glands.

In a series of patients drawn from the Birmingham Regional Cancer Registry (England) with tumours of the salivary glands, a significant excess of second primary tumours was observed. For females, the excess was found mainly in breast and bronchus and, for males, in prostate and skin. In a parallel series of female breast-cancer patients, the observed number of second primary tumours in salivary glands significantly exceeded expectation. These results support the reported association between salivary gland and breast cancer, and suggest that other hormone-dependent sites are also at risk.


Classification of the types of androgenetic alopecia (common baldness) occurring in the female sex.

Androgenetic alopecia in the female occurs much more frequently than is generally believed. The condition is still considered infrequent, for it differs, in its clinical picture and in the sequence of events leading to it, from common baldness in men. To facilitate an early diagnosis (desirable in view of the therapeutic possibilities by means of antiandrogens) a classification of the stages of the common form (female type) of androgenetic alopecia in women is presented. The exceptionally observed male type of androgenetic alopecia can be classified according to Hamilton or to the modification of this classification proposed by Ebling & Rook.


Vitiligo: a new classification and therapy.

Local injection of physostigmine revealed that dermatomally distributed vitiligo was associated with a dysfunction of the sympathetic nerves in the affected skin and that non-dermatomally distributed vitiligo was not. These observations led to the hypothesis that the primary disturbance of dermatomally distributed vitiligo lies in the sympathetic nerves of the affected area and that non-dermatomally distributed vitiligo has its primary disturbance in the melanocyte itself, where an autoimmune mechanism is suspect. Results of therapy supported this hypothesis by showing that topical cortisteroid is effective only in the latter, while the former reacts to oral nialamide. It is proposed that non-dermatomally distributed vitiligo be referred to as Type A and dermatomally distributed vitiligo as Type B.


Depigmented haloes associated with the involution of flag warts.

Depigmented haloes developed around involuting flat warts in two patients whose warts were treated with a 6% salicylic acid-propylene glycol gel formulation. The clinical picture was indistinguishable from that seen in halo naevus.


Eruptive naevi: report of two cases, with enzyme histochemical, light and electron microscopical findings.

The cases of two young adults with widespread multiple eruptive naevi are described. In the first patient, more than 100 lesions appeared during a period of 6 months. Young lesions were small flesh-coloured telangiectatic papules; older lesions were larger and verrucose with histological features of cellular naevi. In the second patient, a great number of lentigines developed in the course of 2 years. Light and electron microscopy showed that giant melanosomes were present within the lesions. The plasma level of beta-MSH-like immuno-reactivity was normal.


Light sensitivity in mycosis fungoides.

Because of suspected photosensitivity, twelve patients suffering from mycosis fungoides have been phototested with various wavebands. Four patients experienced a burning sensation and erythema following sun-exposure, after the disease had progressed to stage II. On phototesting, abnormal reactions were observed in 7 patients. The offending wavebands were situated mostly in the UVA range, but also in the UVB range and in visible light.


Influence of wind on chronic ultraviolet light-induced carcinogenesis.

Wind enhances the carcinogenic effect of chronic Iltraviolet radiation (UVL). This was demonstrated in hairless mice that were irradiated for 42 weeks with mercury are lamps. One group of animals was exposed to continuous wind flow of 2.7 m/s except for the daily I-2 min time interval when they were removed from the wind tunnel and irradiated. Another group of animals received identical irradiation but were protected from wind. The first tumour appeared in the UVL and wind group after 105 days of irradiation, and at 164 days of irradiation all surviving mice in the group had developed tumours. The group of mice receiving identical irradiation but protected from wind had their first tumour appear at 154 days of irradiation, and by 164 days of irradiation only 40% of the mice had developed tumours.


Psoriasis and stress.

132 psoriasis patients who had been completely cleared with dithranol were assessed and then followed up over a 3-year period. The incubation time from specific incidents of stress to the development of psoriasis was between 2 days and 1 month. Specific stress within a month before the first attack was recalled by 51 patients (39%); chance association was excluded by studying a control group where there was significantly less specific stress. The prognosis for the psoriasis patients who recollected specific stress a month prior to the onset was significantly better than for the rest of the patients where none had been recalled.


Cutaneous beta-glucuronidase: cleavage of mycophenolic acid by preparations of mouse skin.

Mycophenolic acid, a new chemotherapeutic agent for the treatment of psoriasis, is known to be rapidly conjugated on absorption and to circulate largely in the form of its glucuronide conjugate. Since this metabolite does not readily penetrate intact cells and is cleaved by the enzyme beta-glucuronidase to yield free mycophenolic acid, the ability of preparations of mouse skin to cleave mycophenolic glucuronide was studied. The time course of mycophenolic acid liberation by such preparations and the dependence upon the amount of enzyme preparation were demonstrated. Preparations of mouse skin and mouse liver, kidney, spleen, lung, heart and small intestine were assayed for beta-glucuronidase activity using p-nitrophenyl-beta-D-glucuronide as substrate. Skin yielded preparations with higher beta-glucuronidase activity per/mg protein than any of the other organs tested. When expressed on the basis of beta-glucuronidase activity recovered per milligram of tissue DNA, skin, liver and kidney showed higher levels than the other organs tested.


Post-kala-azar dermal leishmaniasis.

Ten patients with post-kala-azar dermal leishmaniasis (2 females, 8 males-aged 17-47 years) are described. Two of them had macular lesions in which very few Leishman-Donovan bodies were seen and who responded well to treatment with stibophen. Five patients had both macular and nodular lesions, Leishman-Donovan bodies being present in nodules but not in macules. Treatment with stibophen caused partial regression of nodules. Nodular lesions were found in three patients, who did not have macules. They contained numerous Leishman-Donovan bodies and treatment produced only temporary improvement. The variable response to treatment with stibophen may have been due to differences in parasitic load. The difficulty in distinguishing this disease from leprosy is discussed.


Generalized eczéma craquelé as a presenting feature of lymphoma.

Two cases of lymphoma are reported--in both, extensive eczéma craquelé resistant to treatment was a presenting feature.


Acquired ichthyosis: multiple causes for an acquired generalized distrubance in desquamation.

Four patients with acquired ichthyosis are described and the results of histological, histometric, autoradiographic and enzyme histochemical studies reported. Three of the patients were found to have in addition the following underlying diseases--malnutrition, reticulum cell sarcoma and panhypopituitarism. The fourth patient did not have any systemic disorder and the provoking cause of his ichthyotic condition remains obscure. Clinically these patients demonstrated the skin changes of autosomal dominant ichthyosis although their condition tended to fluctuate in severity. The various studies performed indicated that the histological and metabolic changes tended to reflect the clinical state of the patients and that these parameters did not differ significantly from those observed in atuosomal dominant ichthyosis.


Darier's disease: a kindred with a large number of cases.

Over 70 cases of keratosis follicularis (Darier's disease) were noted in a study of a single kindred consisting of more than 200 individuals. Data were obtained through questionnaires, interviews and physical examinations. Results strongly support an autosomal dominant mode of inheritance since the ratio of affected to unaffected members was I:I and there were nearly equal numbers of males and females with this condition. Large sibships were common in this kindred, which extended over seven generations, and most of the affected individuals were located in the southwestern New York-northwestern Pennsylvania region of the United States.


Obstetric practice and infant morbidity.

A method is described of using matched pairs of index infants and controls to examine the hypothesis that induction or some other obstetric practice is associated with increased morbidity in the mature infant. All infants over 2250 g and 37 weeks gestation, without severe congenital defect or history of severe maternal disorder, born in the John Radcliffe and admitted to the Special Care Baby Unit in 1975 were identified. For each of these index infants a matched control was chosen using strict criteria. Contrast between the 109 matched pairs showed no significant differences between maternal characteristics, induction of labour, use of forceps or duration of labour. There was an excess of index infants born to mothers who had had epidural anaesthesia (P less than 0.05).


Pregnancy and the acute porphyrias.

An analysis is presented of the obstetric histories of 50 women with acute porphyria, comprising 39 with acute intermittent porphyria, 3 with variegate porphyria and 8 with hereditary coporporphyria. Fifty-four per cent of the women with acute intermittent porphyria had an acute attack of porphyria in pregnancy and/or the puerperium. Only one maternal death was recorded. One patient with variegate prophyria and two with hereditary coproporphyria had an attack related to pregnancy. The total fetal wastage was 13 per cent. The babies born to mothers with acute intermittent porphyria, who experienced an acute attack during pregnancy, were smaller than those in which no such attack occurred (P less than 0.001). In 13 non-porphyric primigravidae there was a rise in urinary excretion of delta-aminolaevulinic acid, porphobilinogen and coproporphyrin up to the 28th week of gestation. It is probable that pregnancy has some deleterious effects in acute prophyria but the prognosis of the porphyric pregnancy is much better than the literature suggests.


Nonspecific decelerations in fetal heart rate during high-risk pregnancy.

Solitary nonspecific decelerations in fetal heart rate occurring in three patients during antepartum cardiotocography are described. The decelerations were nonspecific in that they were neither variable nor late nor associated with maternal hypotension. All occurred in pregnancies complicated by hypertension and placental insufficiency. In the three patients described, the fetus lived for at least three days after the first nonspecific deceleration was observed. Although solitary nonspecific decelerations may indicate may indicate danger to the fetus from placental insufficiency, these decelerations should not be considered as an indication for immediate delivery.


The uterine and cardiovascular effects of oral fenoterol hydrobromide.

Fenoterol hydrobromide was administered as a 5 mg tablet to 10 patients in oxytocin-induced labour and the effects on uterine activity and on the cardiovascular system of mother and baby were evaluated. The drug took effect within 30 minutes in 8 of the 10 patients and it reduced uterine activity to less than 30 per cent of the original. Fenoterol caused a moderate maternal tachycardia, raised systolic and decreased the diastolic blood pressure.


Circulating levels of pregnancy-specific beta1-glycoprotein in early pregnancy.

Circulating levels of pregnancy-specific beta1-glycoprotein (SP1 or PSbetaG), luteinizing hormone (LH) and human chorionic gonadotrophin (HCG) were measured serially in 9 subjects immediately after conception. Ovulation occurred spontaneously in 3 subjects, or followed administration of clomiphene citrate (2 subjects) or bromocriptine (4 subjects). The timing of ovulation was determined by the appearance of the LH surge. Levels of HCG were detected 10 to 16 days, and SP1, 18 to 23 days after ovulation. These findings suggest that the measurement of plasma levels of SP1 may provide valuable additional biochemical evidence of pregnancy.


Changes in prostaglandin F and 13,14-dihydro-15-keto-prostaglandin F concentrations in amniotic fluid at the onset of and during labour.

Concentrations of prostaglandin F (PGF) and its major circulating metabolite 13,14-dihydro-15-keto-PGF (PGFM) have been measured in amniotic fluid during spontaneous labour at term. Levels of both PGF and PGFM were significantly higher during early spontaneous labour, at a cervical dilatation of less than 4 cm, than before the onset of labour. Patients who started labour spontaneously but later required oxytocin therapy for failure to progress in first stage had lower levels of PGF and PGFM than patients who progressed adequately without oxytocin therapy. During spontaneous labour, concentrations of both PGF and PGFM increased significantly with advancing cervical dilatation. These indicate that the accumulation of prostaglandins in amniotic fluid during labour is not due to decreased metabolism. They furthermore provide the strongest evidence available so far for an increase in intrauterine prostaglandin synthesis during human parturition.


Epidemiological features of perinatal death due to obstructed labour in Addis Ababa.

Obstructed labour was the second most common cause of perinatal death in Addis Ababa, Ethiopia, being responsible for 9.1 perinatal deaths/1000 births. Most obstructed labours were due to cephalopelvic disporportion. There was a ninefold increase in the perinatal death rate when the patients were anaemic but most perinatal deaths were due to delays in seeking available obstetrical care. Formal education of the patients had little influence on the death rates but the informal education that comes with prolonged urban residence had a markedly favourable effect. Use of prenatal medical services and adequate income also had a favourable influence.


Measurement of menstrual blood loss in patients complaining of menorrhagia.

A study has been made of menstrual blood loss measured in 50 women with unexplained heavy loss (more than 80 ml). Twelve of these women had an average menstrual loss greater than 200 ml, five women in excess of 450 ml. There was no relation between the duration of menstruation and the total menstrual blood loss. Compared to women with normal menstrual loss there was no difference either in the proportion of total menstrual loss passed on each day of menstruation in women bleeding heavily (92 per cent of the total menses being lost in the first three days) or in the coefficient of variation for menstrual blood loss from one period to the next. There was a reduction in menstrual blood loss in the first period following uterine curettage but no effect thereafter.


Endocrine changes and symptomatology after oophorectomy in premenopausal women.

The symptomatic and endocrine changes following hysterectomy and bilateral oophorectomy have been studied in 100 patients, 1 to 31 years after surgery. The most frequent symptoms at the time of interview were depression (62 patients), insomnia (48 patients), loss of libido (46 patients) and dyspareunia (38 patients). Vasomotor symptoms were recorded in 28 patients. Although 94 patients claimed that hot flushes were the first symptomatic changes noticed, 60 had complete relief from these symptoms within 6 months of surgery; 34 patients had no symptoms and only 4 patients were taking oestrogen therapy at the time of interview. Plasma oestradiol and testosterone levels were 78 per cent and 27 per cent respectively below the mean values of day 1 to 10 of the menstrual cycle, similar to those found at comparable years after a normal menopause. The plasma FSH level was about 14 times and the plasma LH level about twice the respective preoperative value. Unlike after the normal menopause, these gonadotrophin levels did not show any decline with increasing age. There was no correlation between plasma hormone levels and the presence of vasomotor symptoms or depression.


Hodgkin's disease diagnosed in pregnancy, case report.

A patient is described in whom Hodgkin's disease was diagnosed and treated during the antenatal period, and who was delivered of a premature, but otherwise normal, infant.


beta-Thalassaemia trait in a pregnant girl of British stock.

A pregnant patient with anaemia due to beta-thalassaemia trait is described. The patient was apparently of British stock.


Observations on the retinal pigment epithelium and retinal macrophages in experimental retinal detachment.

After experimental retinal detachment in rabbits macrophages are a prominent feature in the subretinal space or within the retina. Two sources for these macrophages are identified. The retinal pigment epithelium (RPE) may undergo metaplasia and actively 'bud'; the evolving macrophage is then formed by a vitreal protrusion of the cytoplasm of an RPE cell which is 'nipped off' by lateral protrusions from adjacent cells. In addition, in regions of RPE proliferation, blood-borne cells were found in Bruch's membrane and among the mass of proliferated RPE cells, suggesting that blood-borne cells may pass from the choroidal circulation through Bruch's membrane and the RPE layer.


Structural changes in the outer retinal layers following blunt mechanical non-perforating trauma to the globe: an experimental study.

Structural changes in the external retinal layers of pigs' eyes that had previously been subjected to blunt non-perforating mechanical injuries have been described. Within minutes of trauma fragmentation of the photoreceptor outer segments and damage to the retinal pigment epithelium was recorded in areas of retina adjacent to the missile impact site on the sclera. One week after injury the disrupted photoreceptor outer segments disappeared, and the inner segments came to lie adjacent to the retinal pigment epithelium. Evidence of regeneration of photoreceptor outer segments was noted 2 weeks later.


Retinal detachment treated with intravitreal air: an evaluation of 241 cases.

241 unselected cases of retinal detachment treated since 1971 with cryopexy and intravitreal air are discussed. The series is analysed according to the position of the retinal tears(s), and we describe briefly the surgical technique and evaluate the main complications.


Infection following retinal detachment surgery.

Since the introduction of gentamicin (given both as a soaked sponge and as an injection below Tenon's capsule at the end of surgery) no case of early infection either with or without intraocular signs after operation for retinal detachment has occurred in a series of 206 cases comprising 243 operations. However, late infection many months after operation has appeared in 3 cases (1-5%), though this rate appears to have been favourably influenced by the administration of gentamicin. Local or systemic side effects from the administration of gentamicin have not been seen, and therefore the sub-Tenon injection in the quadrant where the sponge has been placed is strongly advocated in all cases of surgery for retinal detachment when such sponges are used.


Clinical copper metabolism parameters in patients with retinitis pigmentosa and other tapeto-retinal degenerations.

Reports have appeared of abnormal copper metabolism in retinitis pigmentosa, and of a family with vitelliform retinal degeneration in which other members suffered from hepatolenticular degeneration. In the present study 15 patients with retinitis pigmentosa, 4 with various other retinal degenerations, and 1 with a family disposition to retinitis pigmentosa were examined. The copper concentration in serum and the coeruloplasmin concentration in plasma were found to be within normal limits. In 9 of the patients with retinitis pigmentosa the urinary excretion of copper per 24 hours was determined and was found to be normal. The results of the present study lend no support to the hypothesis of abnormal copper metabolism in retinitis pigmentosa.


The association of retinitis pigmentosa with preretinal macular gliosis.

A retrospective study of the histopathological features of retinitis pigmentosa was undertaken. A consistent finding in 10 out of 10 eyes from 6 patients with retinitis pigmentosa was the presence of a preretinal membrane. The frequency of this finding has not been noted previously. Preretinal gliosis may well be responsible for the production of the abnormal glinting fundus reflex seen at the posterior pole in retinitis pigmentosa.


Late ocular manifestations in neonatal herpes simplex infection.

Five patients who had had neonatal herpes simplex virus infection were re-examined at ages that varied from 6 to 9 years. In all of them the diagnosis had been supported by virus isolation and antibody titration, and herpes virus type 2, the genital strain, had been the causative agent. Only 1 of the patients was mentally retarded. Three of the patients had manifest squint, and only 1 patient had normal visual acuity in both eyes. The fundus changes varied from atrophy of the retinal pigment epithelium in 3 patients to atrophy of the optic disc in 2 eyes and extreme tortuosity of the retinal arterioles and veins in 1 patient. One patient developed bilateral retinitis with exudation into the vitreous at the age of 5 years. Fluorescein angiography of this patient showed peripheral vascular closure and preretinal neovascularisation, with leakage in both eyes. This may have been due to chronic retinal vasculitis; haemorrhagic infarction may have induced the damage to retinal tissues. Laser photocogulation resulted in slight improvement of the visual acuity, clearing of the vitreous, and decrease of the fluorescein leakage.


Energy transfer between terbium and iron bound to transferrin: reinvestigation of the distance between metal-binding sites.

The addition of trivalent iron, gallium, and terbium ions to the metal binding sites of human transferrin has been investigated by fluorescence and spectrophotometric measurements. Results are consistent with the possibility that the addition of ferric nitrilotriacetate to apotransferrin does not lead to a random distribution of iron bound to the two metal-binding sites on the protein, but rather an asymmetric distribution with iron bound mainly to one of the sites. The subsequent addition of terbium leads to the binding of terbium ions to the vacant sites on monoferric transferrin molecules, and observations of the intensity of terbium fluorescence from such samples provides clear evidence of transfer of excitation energy from the terbium site to the iron site. These results lead to the estimate that the two metal-binding sites of human transferrin are separated by a distance of 25 +/- 2 A, in disagreement with an earlier report (Luk, C. K. (1971), Biochemistry 10, 2838) that the sites were separated by more than 43 A. Consideration of the dimensions of transferrin indicates that the two sites lie relatively close to each other on the macromolecule.


Fluorescence depolarization studies on the flexibility of myosin rod.

The single photon counting method has been used to measure the decay of fluorescence polarization anisotropy of myosin rods labeled with extrinsic fluorophores. Rods labeled with 8-anilino-1-naphthalenesulfonate (ANS) or 5-dimethylaminoaphthalene-1-sulfonyl chloride (DNS-Cl) exhibit negative rotational correlation times; the anisotropy increases with time. Possible artifactual causes for the negative decay times are ruled out. It is shown that such curves are to be expected for rigid rods when the fluorophore is bound so that the absorption and emission dipoles each make a small angle with the long axis of the molecule and lie on opposite sides of the rod. At pH 4 and below, rapid decay of the anisotropy (positive correlation times) indicates the presence of a freely bending region in the rod. This is probably the proteolytically sensitive region between light meromyosin and heavy meromyosin subfragment 2. At pH 8, no such free bending is observed, even at temperatures as high as 50 degrees C. From this observation and other physical properties of the rod, we conclude that, at pH 8, the hinge region has considerable resistance to bending. It is more like a spring than a free hinge. The rotational diffusion about the rod axis is faster than would be predicted for a rigid, smooth molecule.


Molecular homogeneity of the histone content of HeLa chromatin subunits.

Interaction of affinity chromatographically purified antihistone H3 and antihistone H4 with isolated HeLa core particles, followed by separation of unreacted and reacted particles by sedimentation, demonstrates that every core particle contains these histones. Taken together with our previous data indicating the presence of H2B in every nucleosome (Simpson, R. T., and Bustin, M. (1976), Biochemistry 15, 4305), these data lead to the conclusion that each core particle contains two each of the four smaller histones. In contrast to the lack of interference in binding of more than one molecule of antibody to a single species of histone to the core particle, steric hindrance exists when attempts are made to bind both anti-H3 and anti-H4 to core particles.


Absolute configuration of tritiated O-alkylglycerol synthesized enzymatically from (1,3-3H2, 1,3-14C2)dihydroxyacetone phosphate.

O-Alkyldihydroxyacetone phosphate is synthesized enzymatically from hexadecanol and acyldihydroxyacetone phosphate. In this process there is a hydrogen exchange in which the pro-R hydrogen of C-1 of the sn-glycerol moiety is lost. This hydrogen is replaced by a hydrogen from the medium. In order to obtain additional information on the mechanism of ether bond formation, it would be of interest to know whether or not the hydrogen exchange results in a change of configuration in the product, O-alkyldihydroxyacetone phosphate. By using O-alkylglycerol prepared both chemically and enzymatically from isomerase-treated [1,3-3H2, 1,3-14C2] dihydroxyacetone phosphate and an O-alkylglycerol cleavage enzyme system, it was shown that the hydrogen exchange occurs with retention of configuration of the substituents of C-1 of the sn-glycerol moiety.


Reconstitution of chromatin core particles.

Chromatin core particles, containing 140 base pairs (bp) of DNA plus the inner histones, can be nearly quantitatively formed either by reassociation from 2 M NaCl or by reconstitution from salt extracted histones and DNA. The reassociated or reconstituted particles appear to be identical with the native particles in all physical properties examined (sedimentation velocity, histone content, circular dichroism, and melting) as well as in their patterns of digestion by micrococcal nuclease, DNase I, and trypsin. In the presence of excess DNA, no "half-particles" are formed. In the presence of excess histone, aggregated structures are formed in addition to 11S core particles.


Inhibition of deoxyribonucleic acid chain initiation: a new mode of action for 1-beta-D-arabinofuranosylcytosine in human lymphoblasts.

A novel biochemical effect of 1-beta-D-arabinofuranosylcytosine (ara-C) on DNA replication in cultured human lymphoblasts is described. By incubating the cells with [3H] thymidine for 5 min and analyzing the nascent DNA by velocity sedimentation in alkaline sucrose gradients, it was possible to discern the initial effect of a very low concentration of drug (5 nM) on DNA replication. During the first 30 min of incubation, ara-C inhibited the initiation of new replicating units of DNA but did not affect the elongation of previously initiated units. A later effect was the reduction of the rate of DNA chain elongation. A model, based on the incorporation of ara-C into nascent DNA, is presented to account for a differential effect of the drug on DNA chain initiation and elongation in mammalian cells.


Circular dichroism of cobaltous complexes of creatine kinase.

Circular dichroic spectra in the visible wavelength region were used to investigate the local environment of Co(II), an activating metal, at the active site of rabbit muscle creatine kinase. There was a small spectral change when CoADP- was bound to creatine kinase, no change when creatine was added, and another small change when NO3- was added to form the transition state analogue. Using matrix rank analysis to quantitate these small spectral changes, a titratable group with a pK = 7.4 was found which modified the enzyme-bound metal-nucleotide interaction. These data suggest that, throughout the enzyme's catalysis, the metal-nucleotide interaction remains very similar in structure to the complex not bound to the enzyme.


Fluorescent probes in model membranes I: anthroyl fatty acid derivatives in monolayers and liposomes of dipalmitoylphosphatidylcholine.

A study of three fluorescent anthroyl probes has been carried out using pure and mixed monomolecular films with dipalmitoylphosphatidylcholine. In addition, fluorescence depolarization and differential scanning calorimetry data were obtained from dipalmitoylphosphatidylcholine vesicles with incorporated anthroyl probes. The three probes used were 2-(9-anthroyl)palmitic acid. 12-(9-anthroyl)stearic acid, and 16-(9-anthroyl)palmitic acid. The latter probe was synthesized for these studies. In monolayers the probes shifted the onset of the liquid-condensed/liquid-expanded monolayer phase transition with the extent of the shift decreasing in the order: 2-(9-anthroyl)palmitic acid greater than 12-(9-anthroyl)stearic acid greater than 16-(9-anthroyl)stearic acid. A corresponding decrease in the gel-liquid crystalline bilayer transition temperature (Tc) showed the same order of perturbation in both the fluorescence depolarization and differential scanning calorimetry data. Locating the anthroyl entity in the center of the bilayer would appear to provide a minimum perturbation.