Immunocytochemical and in situ hybridization studies of the heparan sulfate proteoglycan, glypican, in nervous tissue

Using immunocytochemistry and in situ hybridization histochemistry, we have investigated in embryonic and postnatal rat nervous tissue the localization and cellular sites of synthesis of glypican, a glycosylphosphatidylinositol-anchored heparan sulfate proteoglycan. Glypican immunoreactivity is present in the marginal layer (prospective white matter) and in the dorsal root entry zone of E13-16 spinal cord, as well as in the optic nerve and retina at this stage, but does not appear at significant levels in brain until approximately E19. The proteoglycan shows a wide distribution in grey matter and axonal projections of postnatal brain, including the hippocampal formation, the parallel fibers of cerebellar granule cells, and in the medulla and brainstem. Northern analysis demonstrated high levels of glypican mRNA in brain and skeletal muscle, and in rat PC12 pheochromocytoma cells. In situ hybridization histochemistry showed that glypican mRNA was especially prominent in cerebellar granule cells, large motor neurons in the brainstem, and CA3 pyramidal cells of the hippocampus. Our immunocytochemical and in situ hybridization results indicate that glypican is predominantly a neuronal membrane proteoglycan in the late embryonic and postnatal rat central nervous system.

Presence of regulatory sequences within intron 4 of human and murine c-myb genes

The molecular mechanisms that modulate c-myb mRNA transcription in hematopoietic cells appear to involve intron regulatory sequences. We have characterized the fourth of ten introns from both human and murine c-myb genes in regard to nucleotide sequence and specific protein binding. For this approach complete genomic c-myb intron 4 fragments were isolated from mouse and human DNA using PCR amplification with flanking exon-primers derived from the mouse gene. Comparison of the obtained sequences revealed strong homology between the two species. Using crude nuclear protein extracts from mouse and human myb expressing cells (70Z/3B; Molt4) and gel shift experiments we found specific protein interaction for both introns and to determine the protein binding site in detail, we performed DNase I footprinting. Our results indicate that the binding factor is absent in control cell lines without c-myb transcriptional activity, suggesting a possible positive regulatory function of the DNA-protein complex. To confirm these findings we introduced the human c-myb intron 4 DNA sequence into the EcoRI site of the pCAT-Promoter plasmid and transfected Molt4 cells with this chimeric construct. The transient expression studies revealed that intron 4 sequences possess enhancer activity. Thus, we have demonstrated that intron 4 sequences can be important for the regulation of c-myb proto-oncogene expression.

Squamous cell carcinoma of the lung: does the nm23 gene expression correlate to the tumor stage?

We examined the nm23 gene activity in 30 human squamous cell carcinomas of the lung using the Northern blot analysis. Matched healthy lung tissue was available from 10 patients. 26 tumor samples were obtained after resection treatment between 1986 and 1990, 4 additional samples of advanced stages from autopsy. We found a significant increase of nm23 expression towards advanced stages of squamous cell carcinoma (IIIa vs. I: p < 0.015, IV vs. II: p < 0.043, IV vs. I: p < 0.043). Furthermore in stage I and II, poorly differentiated squamous cell carcinomas contained significantly more nm23 mRNA than did moderately differentiated ones (p < 0.027). We could also demonstrate an inverse correlation between the levels of nm23 mRNA and disease-free survival after resection treatment (p < 0.016, chi 2-test for trend). Thus the nm23-gene activity correlates to the tumor stage and the grade of differentiation of the squamous cell carcinoma of the lung, and is therefore of prognostic relevance. It might be possible to describe the biological behaviour of the individual tumor more accurately by the additional measurement of the nm23 mRNA.

Kinetics of inhibition by tyrphostins of the tyrosine kinase activity of the epidermal growth factor receptor and analysis by a new computer program

The kinetics of inhibition of the epidermal growth factor (EGF) receptor (EGFR) tyrosine kinase (TK) activity by erbstatin, tyrphostins, and lavendustin derivatives were studied in a system that employs poly(Glu6Ala3Tyr) (GAT) and ATP as substrates, after preactivation with EGF. All data were analyzed for computer best-fit curves by a program that was written for this purpose and is available upon request to those interested. The inhibition kinetics followed a sequential, Bi-Bi, rapid equilibrium, random mechanism, the mechanism of the EGFR-TK. Erbstatin and a few tyrphostins that contain a 3,4-dihydroxy-(cis)-cinnamonitrile [1-(3',4'-dihydroxyphenyl)-2-nitriloethene] group were found to be pure competitive inhibitors with respect to both substrates of the kinase reaction, i.e., GAT and ATP. Two tyrphostins, each containing an additional dihydroxyphenyl group in the alpha-position, were found to be pure competitive inhibitors with respect to GAT and noncompetitive (or mixed-competitive) inhibitors with respect to ATP. A lavendustin derivative with a 2,5-dihydroxyphenyl ring and a lavendustin derivative with a 3,4-dihydroyphenyl ring were also found to be competitive inhibitors with respect to both ATP and GAT. Various possible modes of binding at the EGFR-TK active center for the tyrphostins studied are proposed and the significance of the present findings, as well as the interpretations of computer analyses of kinetic data, is discussed.

Phosphorylation of nm23/nucleoside diphosphate kinase by casein kinase 2 in vitro

We have investigated phosphorylation of human nucleoside diphosphate kinase (NDPK) and of homologous NDPK from different species by human casein kinase 2 (CK-2). The human NDPK isotypes A and B were phosphorylated by CK-2 in vitro both when the purified proteins and total lysate of HL-60 leukemia cells were used. The homologous NDPK's from Yeast and E. coli were also substrates for CK-2 in vitro, but not Drosophila NDPK. Phosphorylation of all NDPK types by the CK-2 holoenzyme was entirely polyamine-dependent. The CK-2 phosphorylation site in human NDPK A, that was about 2.5 times stronger phosphorylated than was the B isotype, was tentatively assigned to Ser-122. The location of the corresponding residue in the 3D-structure of the 80% homologous Drosophila NDPK suggests that its phosphorylation may directly influence substrate binding and/or catalysis.

Disaccharide composition of heparan sulfates: brain, nervous tissue storage organelles, kidney, and lung

We have characterized the structural properties of heparan sulfates from brain and other tissues after depolymerization with a mixture of three heparin and heparan sulfate lyases from Flavobacterium heparinum. The resulting disaccharides were separated by HPLC and identified by comparison with authentic standards. In rat, rabbit, and bovine brain, 46-69% of the heparan sulfate disaccharides are N-acetylated and unsulfated, and 17-21% contain a single sulfate residue in the form of a sulfoamino group. In rabbit, bovine, and 1-day postnatal rat brain, disaccharides containing both a sulfated uronic acid and N-sulfate account for an additional 10-14%, together with smaller and approximately equal proportions (5-9%) of mono-, di-, and trisulfated disaccharides having sulfate at the 6-position of the glucosamine residue. Kidney and lung heparan sulfates are distinguished by high concentrations of disaccharides containing 6-sulfated N-acetylglucosamine residues. In chromaffin granules, the catecholamine- and peptide-storing organelles of adrenal medulla, where heparan sulfate accounts for a minor portion (5-10%) of the glycosaminoglycans, we have determined that bovine chromaffin granule membranes contain heparan sulfate in which almost all of the disaccharides are either unsulfated (71%) or monosulfated (18%). In sympathetic nerves, norepinephrine is stored in large dense cored vesicles that in biochemical composition and properties closely resemble adrenal chromaffin granules. However, in contrast to chromaffin granules, heparan sulfate accounts for approximately 75% of the total glycosaminoglycans in large dense-cored vesicles and more closely resembles heparin, insofar as it contains only 21% unsulfated disaccharides, 10% mono- and disulfated disaccharides, and 69% trisulfated disaccharides.(ABSTRACT TRUNCATED AT 250 WORDS)

Isolation and characterization of the human genomic locus coding for the putative metastasis control gene nm23-H1

Nm23-H1 gene expression is inversely correlated with tumor metastatic potential in certain tumors, including melanomas, breast carcinomas, and hepatocellular carcinomas. Using nm23-H1 c-DNA primer and genomic polymerase chain reaction (PCR) amplification, we purified three PCR fragments (one of 4kb and two of 2 kb) covering the whole human genomic locus of the gene (8.460bp). We recombined the PCR products into pUC18 and produced a restriction map to perform subcloning. Complete sequencing of genomic PCR fragments, including the whole coding region of nm23-H1, revealed that the gene consists of five exons and four introns spanning 8.5kb. A sequence homology analysis between human nm23-H1 and the homolog gene of the rat (NDP-K beta) shows that exon-intron boundaries are well conserved between these two species.

[The dynamics of blood composition changes in leukocyte filtration during cardiopulmonary bypass. Preliminary results]

Activation of leukocytes (especially neutrophils) during cardiopulmonary bypass (CPB) causes a reperfusion injury through the release of oxygen free radicals and formation of microvascular occlusions. Leukocyte filtration during CPB could solve these drawbacks. We investigated the selectivity of leukocyte filtration by fifteen patients undergoing coronary artery bypass surgery. Leukocyte depleted patients (n = 8) had a leukocyte filter incorporated in the bypass circuit. We evaluated the number of lymphocytes, neutrophils and platelets as well as hematocrit values at following time points: a) before CPB, b) 15 min after the start of CPB, c) before the administration of protamin and d) 3 hours after the CPB. No statistically significant changes of hematocrit values, lymphocyte or platelet counts between control and leukocyte depleted group of patients were observed. However, the use of leukocyte filter caused significant decrease in number of circulating neutrophils at 15 min after begin of CPB (1.20 +/- 0.17 x 10(9)/l for leukocyte depleted patients and 1.90 +/- 0.42 x 10(9)/l for control group of patients, p < 0.05). Our temporary results indicate the selectivity of leukocyte filtration during the cardiopulmonary bypass.

High levels of nm23-H1 and nm23-H2 messenger RNA in human squamous-cell lung carcinoma are associated with poor differentiation and advanced tumor stages

Expression of the candidate metastasis-suppressor gene nm23-H1 has been shown to correlate inversely with metastatic potential in some human tumors, but not in all. Until now, few studies have been carried out on the activity of the homologous nm23-H2 gene in human cancer. No nm23 transcription studies exist for human lung cancer so far. To determine whether the nm23 genes could have a metastasis-suppressor function in non-small-cell lung carcinoma (NSCLC), pulmonary sarcoma and carcinoids, we analysed both nm23-HI and nm23-H2 mRNA levels in 37 tumor samples obtained from patients who underwent potentially curative resection between 1986 and 1990, and in 4 metastatic tumors obtained from autopsy. As compared to corresponding healthy lung parenchyma, both nm23-HI and nm23-H2 transcript levels were elevated in 37 of 41 tumors. The increases in nm23 mRNA expression were stronger in advanced stages of squamous-cell carcinoma, large-cell carcinoma, sarcoma and carcinoids than in early stages of the respective tumor types. Within stages I and II of squamous-cell carcinoma, significantly higher nm23 mRNA levels were found in poorly differentiated tumors than in moderately differentiated ones. Moreover, an inverse correlation between nm23 expression and disease-free survival of the patients was observed. In conclusion, our results indicate that the increased nm23 expression in the analysed tumors is not consistent with the proposed metastasis-suppressor function, but the 2 nm23 genes nevertheless may be implicated in the mechanism of tumor progression.

[4-fragment fracture of the proximal upper arm]

Four-fragment fractures have to be accorded great importance because they are so severe. The morphology allows differentiation of two types, the dorsolateral fracture type and the impacted fracture type. Over a 4-year time span, 13 of these fractures were treated with minimal osteosynthesis. This involve the open anatomical reduction and allogeneic spongiosa grafting and retention of the fracture with screws and, if necessary, K-wires and tension banding. After an average of 26.3 months the shoulder function was evaluated using the CONSTANT score. The dorsolateral fractures were scored of 87.2 while the impacted fractures were scored at 88.8. No necrosis of the humeral head was found. These good results show that after four-fragment fractures primary reconstruction of the humeral head should be preferred over primary prosthetic replacement.

A rapid method to determine the orientation of blunt end ligated polymerase chain reaction products

Subcloning of polymerase chain reaction (PCR) fragments is often performed via blunt end ligation after previous Klenow fragment exonuclease treatment. Since insert-specific primers are at hand from the original amplification step, we used a simple PCR-based assay to determine the insert orientation of the recombinants. After purification of enriched plasmids, small aliquots were tested performing standard PCR reactions using a plasmid primer directed towards the cloning site and one of the insert specific primers, respectively. Only the distant insert primer yields a PCR product which can be visualized after gel electrophoresis. In this way both the insert orientation in the vector and the correct size of the cloned fragment is determined rapidly without sequencing or restriction fragment analysis.

Kinetic model of the epidermal growth factor (EGF) receptor tyrosine kinase and a possible mechanism of its activation by EGF

The tyrosine kinase activity of the epidermal growth factor receptor (EGFR-TK) was determined at varying poly-Glu6Ala3Tyr1 (GAT) or [Val5]-angiotensin II (AT) and constant ATP concentrations and vice versa. With GAT as substrate, double reciprocal plots intersected practically on the abscissa following EGFR-TK pre-activation with EGF, but below the abscissa without EGF pre-activation. The EGFR-TK inhibitors App(NH)p (5'-adenylyl-beta, gamma-imidodiphosphate) and ADP were competitive with ATP and noncompetitive with GAT. Four families of 1/v vs. 1/[ATP] plots, constructed at different fixed concentrations of ADP and a different constant concentration of GAT for each family, yielded Slope1/ATP replots which intersected to the left of the ordinate and below the abscissa. GAT and AT, as cosubstrates, were competitive with each other and noncompetitive with ATP; 1/v vs. 1/[GAT] or 1/[AT] plots were hyperbolic and reached horizontal asymptotes when v was expressed as the rate of common product formation. All data were subjected to computer best-fit analysis by a program written especially for this purpose. We conclude that (i) the EGFR-TK reaction follows a Sequential Bi-Bi Rapid Equilibrium Random mechanism, and (ii) EGF induces conformational changes in the EGFR-TK active center which lead to marked decreases in the apparent dissociation constants of both substrates of the kinase reaction and a concomitant increase in initial velocities and Vmax (apparent).

A novel galactose- and arabinose-specific lectin from the sponge Pellina semitubulosa: isolation, characterization and immunobiological properties

A new lectin from the sponge Pellina semitubulosa is derived which was extracted and purified to homogeneity. The purified lectin is probably a hexamer of polypeptide chains (each M(r) 34,000) which are covalently linked via disulfide linkages; the isoelectric point is 6.1. The lectin displays the following specificities: D-galactose (50% inhibition of hemagglutination at 0.2 mM) = L-arabinose (0.2 mM) greater than D-fucose (1.5 mM) greater than D-glucose (3.0 mM). It precipitates human erythrocytes (A1, A2, A1B, B, and O) with a titer between 2(8) and 2(11) and erythrocytes from sheep and rabbits with a titer between 2(5) and 2(10). The Pellina lectin displays a strong mitogenic effect on spleen lymphocytes from mice. Immunochemical analyses revealed that both murine T- and B-lymphocytes display a capping of the lectin receptors on their cell surfaces after lectin treatment. Murine macrophages were found to endocytose the lectin. Pellina lectin at concentrations between 0.3 and 10.0 micrograms/ml potently enhances interleukin 1 (IL-1) release from mouse peritoneal macrophages and interleukin 2 (IL-2) production in mixed murine lymphocyte cultures.

Designed coiled-coil proteins: synthesis and spectroscopy of two 78-residue alpha-helical dimers

Receptor-adhesive modular proteins are nongenetic proteins designed to contain ligand, spacer, coil, and linker modules and to interact strongly with integrins or other types of cell-surface receptors. We have designed, chemically synthesized, and characterized a 39-residue peptide chain having a 6-residue ligand module (Gly-Arg-Gly-Asp-Ser-Pro-) for adherence to Arg-Gly-Asp-binding integrin receptors, a 3-residue spacer module (-Gly-Tyr-Gly-) for flexibility, and a 30-residue coil module [-(Arg-Ile-Glu-Ala-Ile-Glu-Ala) 4-Arg-Cys-NH2] containing four 7-residue repeats for dimerization. This chain was designed to form a 78-residue noncovalent dimer (P39) by folding the coils of two chains into an alpha-helical coiled coil through hydrophobic interaction of eight pairs of Ile residues. Air oxidation of P39 gave P78, a 78-residue covalent dimer having a disulfide bridge linking its C termini. Raman spectroscopy indicated that both synthetic proteins have high alpha-helical content. Ultraviolet circular dichroic spectroscopy indicated that both dimers contain stable alpha-helical coiled coils. Its C-terminal disulfide bridge renders P78 significantly more stable than P39 to thermal denaturation or denaturation by urea. The coiled coil of P39 was 30% unfolded near 55 degrees C and half-unfolded in 8 M urea, while that of P78 was 30% unfolded only near 85 degrees C. These studies have demonstrated the feasibility of using these ligand, spacer, and coil modules to construct the designed coiled-coil proteins P39 and P78, a stage in the nanometric engineering of receptor-adhesive modular proteins.

High-level secretion of biologically active aprotinin from the yeastPichia pastoris

A synthetic gene encoding aprotinin (bovine pancreatic trypsin inhibitor) was fused to the Saccharomyces cerevisiae prepro alpha mating factor leader sequence at the dibasic amino acid processing site. Pichia pastoris strains were developed to express one or multiple copies of a methanol-inducible expression cassette containing the gene fusion. P. pastoris containing a single copy of the vector secreted approximately 150 mg/l of immunoreactive protein. A construct bearing five copies of the expression cassette secreted 930 mg/l of aprotinin. The purified aprotinin molecule was equipotent with the native molecule in a trypsin inhibition assay. Protein sequence analysis showed that the alpha factor-aprotinin fusion was not processed at the basic amino acid residues Lys-Arg. Instead, recombinant aprotinin had additional N-terminal amino acids derived from prepro alpha factor. The N-terminal extension was variably 11 or 4 amino acids. Inclusion of the spacer DNA sequence encoding Glu and Ala between aprotinin and the Lys-Arg processing site led to the secretion of a biologically active aprotinin containing only a Glu-Ala N-terminal extension.

Connective tissue disease in southeast Georgia. A community based study of immunogenetic markers and autoantibodies

HLA antigens, C4 allotypes and T cell antigen receptor (TcR)beta DNA polymorphisms were determined in a community based study of connective tissue diseases (CTD). HLA-B8, DR3 and C4A null phenotypes occurred frequently in Caucasian patients with CTD, especially those with systemic lupus erythematosus (SLE), but were also more commonly found among healthy white controls of this southeast Georgia community. TcR beta gene polymorphisms also showed differential segregation patterns between patients with SLE and scleroderma. High frequencies of ANA and anti-ssDNA antibodies occurred among apparently healthy family members and local controls. Genetic factors predisposing to CTD in a community setting appear to be similar to those reported from referral centers.

[The central nervous system arousing effects of ketamine are decreased by addition of midazolam. A post-anesthesia study of patients following maxillary surgery with spontaneous respiration]

The present study was done in order to investigate the central nervous activity in patients (n = 15) after maxillo-facial surgery, 5 and 90 minutes post ketamine-midazolam-anesthesia. The combination of a benzodiazepine with ketamine was thought to be beneficial to reduce the usual excitatory effects after ketamine postoperatively. In order to demonstrate these benefits EEG-power spectra as well somatosensory-evoked potentials were derived (Neurotrac). Additionally, the central nervous effects were correlated with blood pressure changes. 5 minutes post ketamine-midazolam-anesthesia EEG-power spectra showed a marked depression in the alpha, theta and delta power band when compared to the control-awake situation. However, power in the beta domain (13-30 Hz) was significantly elevated. 90 minutes post anesthesia the high power values returned back to control. In no instance were there any signs of theta-paroxysms which can be taken as an index for central excitation. In the evoked potential a significant increase in amplitude of the early N20 and late N50 peak was evident. This correlated with an increase in systolic blood pressure. 90 minutes post anesthesia only the late N50 peak still remained elevated suggesting some residual excitatory effects in the thalamo-cortical projection area to be present. The latter may reflect an increase in activity in the associative cortical areas of the cerebral cortex. In general however, the additional administration of midazolam resulted in a marked reduction in excitatory central nervous effects when compared to the well known excitation after sole ketamine injection. Thus, the beneficial venture of the two separate classes of anesthetics is advocated for clinical practice.

Vaccination and eradication programme against Aujeszky's disease in Sweden, based on a gI ELISA test

A killed gI-negative vaccine combined with a gI enzyme-linked immunosorbent assay (ELISA) test was used for the first time in Sweden in an attempt to eradicate Aujeszky's disease from a weaner pig producing herd. The herd had experienced three severe outbreaks of the disease during a 10 year period and at the start of the programme 96 per cent of the herd's 104 breeding animals were seropositive to the Aujeszky's virus. In addition, there was serological evidence of active virus circulation among younger animals. During the programme, all breeding animals were vaccinated every sixth month and replacement animals were tested free of disease and vaccinated before entry into the herd. When the originally seropositive animals had been rotated out of the herd, all breeding animals and a sample of weaner pigs were tested twice at six weeks' interval. No seroconversions to gI had taken place and the herd was declared Aujeszky's disease-free, 22 months after the start of the programme.

Contribution of oxygen to attenuation in the solar blind UV spectral region

The solar blind ultraviolet (SBUV) spectral region covers the interval between 230 and 290 nm. The lower limit of this interval is given by the edge of the Schumann-Runge band and the upper limit is determined by solar radiation penetrating the stratospheric ozone shield. The SBUV region is interesting from the experimental point of view, since the lack of solar background is favorable in such applications as lidar, atmospheric communications, and remote sensing. The present models (LOWTRAN-6) include as atmospheric attenuators in this region ozone absorption and aerosol and molecular scattering. New theoretical calculations of the Herzberg I oxygen band predict significant absorption by O(2). This prediction is confirmed experimentally in this study. Field measurements at 252, 255, and 264 nm are reported over optical paths of up to 2750 m. Results show that LOWTRAN-6 is inadequate in the SBUV region, as indicated by the present extinction measurements.

The pharmacokinetics of melphalan during intermittent therapy of multiple myeloma

During intermittent melphalan-prednisone therapy the area under the plasma concentration-time curve of melphalan increased by an average of 45% after oral or intravenous administration of the drug in myeloma patients during the initial three courses at six-week intervals. The rise in melphalan plasma concentrations could not be referred to an alteration in melphalan elimination, metabolism, erythrocyte/plasma partition ratio, or protein binding. A possible explanation could be that covalent binding sites of melphalan were successively saturated during intermittent treatment, resulting in higher drug concentrations during successive courses of therapy.

Drawing ability in four young children with congenital unilateral brain lesions

The drawings of four 5-yr-old children, two with left and two right hemisphere congenital brain injury, were compared with those of 20 normal 3.5-5 yr-olds. Two types of drawings were evaluated: copied geometric forms and free drawings. The children with left hemisphere injury showed normal development in both copying and free drawing. The children with right hemisphere injury were developmentally impaired in the copying task. In addition, their free drawings lacked configurational coherence; they included the elements of the figures but failed to arrange them in spatially organized ways. This failure to organize spatially elements is consistent with the descriptions of spatial cognitive disorders found in the drawings of adults with right parietal brain lesions.

Bereitschaftspotential preceding speech after holding breath

Cerebral potentials prior to speaking were recorded in 36 healthy righthanded subjects. Subjects began holding breath at irregular intervals prior to the voluntary onset of speech. This was done in order to avoid respiration-related potential shifts. The Bereitschaftspotential (BP) or readiness potential started already 2 s prior to the onset of speaking and was present over either hemisphere. During the last 100 to 200 ms of preparation period, the BP became significantly lateralized towards the left hemisphere. The close temporal relation to speech onset characterized this hemispheric lateralization to be an indicator of the final motor mechanisms for speech. Still, the BP was a bilateral phenomenon, i.e. it was also present over the right hemisphere, indicating involvement of the non-dominant hemisphere as well. The data are compatible with the view of an early bihemispheric motor preparation for speech followed by a late left hemisphere preponderance as the final common pathway.

Empty sella syndrome in childhood

The empty sella syndrome is common in middle-aged women, usually presenting with headache, and only occasionally associated with endocrine or visual abnormalities. It is rare in childhood. Childhood cases tend to present either with endocrine disturbances, visual symptoms, or with craniofacial syndromes. We present three cases of complete empty sella with childhood onset, each discovered unexpectedly during evaluation of endocrine or visual dysfunction.

Oral immunisation with killed Haemophilus influenzae for protection against acute bronchitis in chronic obstructive lung disease

Fifty patients with chronic obstructive lung disease were randomly allocated to three groups, to assess whether an oral vaccine containing non-typable Haemophilus influenzae protected against acute bronchitis. The double-blind prospective study over a three-month winter period included two placebo groups and one test group. Oral immunisation with H influenzae induced a tenfold reduction in the incidence of infection (p less than 0.001). During the subsequent winter, without further immunisation, protection by the vaccine was no longer statistically significant. There was no clear correlation between clinical protection and either carriage of H influenzae or the level of antibody to H influenzae antigen in saliva.

Progressive dyskinesia due to internal cerebral vein thrombosis

A 9 1/2-year-old boy developed a progressive dyskinesia 7 years after an angiographically demonstrated internal cerebral vein thrombosis. CT revealed bilateral thalamic lesions, more severe on the side contralateral to the movement disorder, without striatal involvement. This is a rare example of survival after internal cerebral vein thrombosis in a child and demonstrates that movement disorders may be delayed consequences of childhood stroke.

Increased intraventricular pressure without ventriculomegaly in children with shunts: "normal volume" hydrocephalus

Five patients with shunt-dependent hydrocephalus were observed to have apparently normal ventricular size despite marked increases in ventricular pressure after shunt malfunction. Elastance (dP/dV) was determined in four of these patients by removing increments of cerebrospinal fluid and measuring the resulting pressure. These patients without ventricular enlargement and with markedly increased ventricular pressure had high elastance. This group of patients with "normal volume" hydrocephalus had distal shunt occlusions, in contrast to previously reported patients with cephalic shunt obstructions after ventricular decompression. Initial shunting in early infancy, prolonged shunt dependency, and lack of recent shunt revision were common factors in these patients. Markedly elevated pressure with normal volume is a threatening clinical entity, requiring prompt surgical intervention