Synthetic inhibitors of tissue kallikrein: effects in vivo in a model of allergic inflammation

We have recently developed synthetic low molecular weight inhibitors of both tissue and plasma kallikreins. Several of these were evaluated in vivo in the ovalbumin-sensitised guinea pig for their ability to prevent the bronchoconstriction elicited by antigen challenge. The selective tissue kallikrein inhibitor CH-694 (but not the selective plasma kallikrein inhibitor CH-684) caused highly significant falls in airways resistance when it was administered at 10 mg/kg intraperitoneally 15 min before and 90 min after challenge. There was also a highly significant fall in the tissue kallikrein activity measured in broncho-alveolar lavage fluid. Inhibitors of tissue kallikrein may prove effective in the treatment of allergic inflammation in man.

Avascular necrosis of the hamate

Avascular necrosis of the hamate is a rare condition, only one case having been reported in the literature (Van Demark and Parke, 1992). This reflects the relative rarity of fractures of the body of the hamate and the arrangement of the intraosseous vascular anatomy. A case is presented, which was diagnosed by MR Imaging and treated surgically.

Endogenous cannabinoid receptor binding activity released from rat brain slices by depolarization

As previously reported by this laboratory, an endogenous factor capable of inhibiting the specific binding of the radiolabeled cannabinoid agonist [3H]CP-55940 to its receptor can be released from nerve terminals in response to an influx of Ca++ induced by an ionophore (Evans et al., 1992). In the present report, we provide evidence that the endogenous ligand for the cannabinoid receptor can be released in response to a depolarizing stimulus (75 mM K+) in the presence of extracellular Ca++. K(+)-evoked release was not observed in the absence of extra-cellular Ca++ and was reduced by the specific calcium channel blockers verapamil and omega-conotoxin. The efflux of cannabinoid receptor binding activity is greatest within 2 min of stimulation with the Ca++ ionophore A23187. Within this period of time, the cannabinoid receptor binding activity was enhanced by the presence of a cocktail of peptidase inhibitors. Examination of the contribution of individual inhibitors for enhancing high K(+)-released material revealed a selectivity for captopril and thiorphan. The specificity of the released factor for the cannabinoid receptor was corroborated by its ability to compete with the aminoalkylindole radioligand [3H]WIN-55212 for binding to this receptor. Fractions from a semi-purified sample of the effluent demonstrated binding to the cannabinoid receptor and behaved as agonists in that these fractions could inhibit adenylate cyclase activity in neuroblastoma membrane preparations.

Median nerve compression following trauma in children. A report of two cases

Two cases of subacute median nerve compression in children following trauma are presented. The first highlights problems of incised wounds around the wrist. The second illustrates an unusual presentation of nerve compression following a blunt injury.

Tendon transfer to restore extension of the thumb using abductor pollicis longus

20 patients with rupture or division of extensor pollicis longus (EPL) underwent tendon transfer using abductor pollicis longus (APL). All patients except one were reviewed and examined between 6 and 80 months after surgery. The subjective and objective results were satisfactory and are presented with details of the technique and its advantages and limitations.

Dose dependency and wound healing aspects of the use of tissue plasminogen activator in the prevention of intra-abdominal adhesions

Intra-abdominal adhesions have been shown to result from the impairment of peritoneal fibrinolysis by inhibitors present in ischemic tissue. A reproducible model for the formation of intra-abdominal adhesions was utilized for the evaluation of the effectiveness of intraperitoneal applications of recombinant tissue plasminogen activator (rtPA) in adhesion prevention. Concentrations of rtPA required to overcome the inhibition of fibrinolysis in this model were estimated by titration of that amount of rtPA required to lyse blood clot in the presence of a measured amount of ischemic tissue. Adhesions were graded, and the hydroxyproline content of the abdominal wounds was analyzed. The effect of intraperitoneal administration of rtPA on adhesion formation was strongly dose related. Levels of rtPA of 0.01 mg/mL showed no effect (p < 0.75) on adhesion formation, whereas levels of 0.1 mg/mL either prevented or significantly modified the formation of intra-abdominal adhesions (p < 0.05). Concomitantly, wound hydroxyproline content was significantly reduced (p = 0.004). Prior investigations have shown a strong correlation between wound bursting strength and hydroxyproline content. The results of this study indicated that the levels of rtPA required to alter or prevent intra-abdominal adhesion formation also produce a significant impairment of the early phase of wound healing as measured by the wound content of hydroxyproline.

A bipedicled neurovascular step-advancement flap for soft tissue lengthening in clinodactyly

Recommendations for the surgical treatment of clinodactyly have centered on techniques of osteotomy with or without bone grafting. However, the limiting factor to the correction may be tension in the soft tissues. A new technique to correct clinodactyly is described utilising an opening wedge osteotomy and bone grafting plus a bipedicled neurovascular step-advancement flap to correct the soft tissue deficiency. The procedure has been performed in five cases.

Molecular cloning and characterization of N-syndecan, a novel transmembrane heparan sulfate proteoglycan

A cDNA clone coding for a membrane proteoglycan core protein was isolated from a neonatal rat Schwann cell cDNA library by screening with an oligonucleotide based on a conserved sequence in cDNAs coding for previously described proteoglycan core proteins. Primer extension and polymerase chain reaction amplification were used to obtain additional 5' protein coding sequences. The deduced amino acid sequence predicted a 353 amino acid polypeptide with a single membrane spanning segment and a 34 amino acid hydrophilic COOH-terminal cytoplasmic domain. The putative extracellular domain contains three potential glycosaminoglycan attachment sites, as well as a domain rich in Thr and Pro residues. Analysis of the cDNA and deduced amino acid sequences revealed a high degree of identity with the transmembrane and cytoplasmic domains of previously described proteoglycans but a unique extracellular domain sequence. On Northern blots the cDNA hybridized to a single 5.6-kb mRNA that was present in Schwann cells, neonatal rat brain, rat heart, and rat smooth muscle cells. A 16-kD protein fragment encoded by the cDNA was expressed in bacteria and used to immunize rabbits. The resulting antibodies reacted on immunoblots with the core protein of a detergent extracted heparan sulfate proteoglycan. The core protein had an apparent mass of 120 kD. When the anti-core protein antibodies were used to stain tissue sections immunoreactivity was present in peripheral nerve, newborn rat brain, heart, aorta, and other neonatal tissues. A ribonuclease protection assay was used to quantitate levels of the core protein mRNA. High levels were found in neonatal rat brain, heart, and Schwann cells. The mRNA was barely detectable in neonatal or adult liver, or adult brain.

Ca(2+)-dependent release from rat brain of cannabinoid receptor binding activity

As a result of the identification, pharmacological characterization, and localization of the cannabinoid receptor in the CNS, the existence of an endogenous ligand for this receptor can be hypothesized. Following the premise that such a substance could have the properties of a neuromodulator being stored in intracellular vesicles, we tested the ability of increased intracellular Ca2+ levels to stimulate release. We demonstrate here that the Ca2+ ionophore A23187 can induce release of cannabinoid-like binding activity in the presence but not in the absence of Ca2+. The effect of A23187 was maximal at 1.2 microM, consistent with vesicular release. It was necessary to increase the concentration of extracellular free Ca2+ to greater than 60 nM to evoke release. The released cannabinoid-like binding activity displaced [3H]CP-55940 binding to cannabinoid receptors in rat synaptosomal membranes in a concentration-dependent manner. This is the first report of a substance present endogenously in brain that can be released in a Ca(2+)-dependent manner and that binds to the cannabinoid receptor.

The wrist in juvenile arthritis

Patients with juvenile arthritis affecting the wrist have been reviewed six months or more after treatment, which has included steroid injection, synovectomy, arthroplasty, arthrodesis and distraction lengthening of the ulna. The pattern of wrist involvement is described, the general management reviewed, and the indications, techniques and results of these various procedures are presented.

Association of cell surface heparan sulfate proteoglycans of Schwann cells with extracellular matrix proteins

The terminal differentiation of Schwann cells is dependent on contact with basement membrane. The present study was undertaken to investigate the role of cell surface heparan sulfate proteoglycans (HSPGs) in mediating Schwann cell responses to extracellular matrix contact. Phosphatidylinositol-specific phospholipase C-releasable cell surface HSPGs purified from cultures of neonatal rat Schwann cells were subjected to affinity chromatography on immobilized laminin and fibronectin. Binding of the HSPG to both affinity matrices was observed. The strength of the association, however, was sensitive to the ionic strength of the buffer. In 0.1 M Tris-HCl, HSPG binding was essentially irreversible whereas in physiological ionic strength buffer (e.g. 0.142 M NaCl, 10 mM Tris), weaker binding was detected as a delay in elution of the HSPG from the affinity columns. Further studies of HSPG-laminin binding suggested that the binding was mediated by the glycosaminoglycan chains of the proteoglycans. Results of equilibrium gel filtration chromatography provided additional evidence for a reversible association of the HSPG and laminin with a Kd of approximately 1 x 10(-6) M. When Schwann cells were plated on plastic dishes coated with laminin, the cells attached and extended long slender processes. Inclusion of heparin, but not chondroitin sulfate, in the assay medium resulted in partial inhibition of process extension, but at concentrations of heparin which were higher than that needed to disrupt laminin-HSPG association in vitro. Addition of anti-integrin receptor antibodies resulted in more extensive inhibition of laminin-dependent process extension. Anti-integrin antibodies plus heparin essentially totally inhibited laminin-dependent process extension. These results demonstrate that cell surface HSPGs are capable of reversible association with extracellular matrix molecules and suggest that HSPG-laminin interactions play a role in laminin-dependent Schwann cell spreading.

Over-expressing a yeast ornithine decarboxylase gene in transgenic roots of Nicotiana rustica can lead to enhanced nicotine accumulation

Transformed root cultures of Nicotiana rustica have been generated in which the gene from the yeast Saccharomyces cerevisiae coding for ornithine decarboxylase has been integrated. The gene, driven by the powerful CaMV35S promoter with an upstream duplicated enhancer sequence, shows constitutive expression throughout the growth cycle of some lines, as demonstrated by the analysis of mRNA and enzyme activity. The presence of the yeast gene and enhanced ornithine decarboxylase activity is associated with an enhanced capacity of cultures to accumulate both putrescine and the putrescine-derived alkaloid, nicotine. Even, however, with the very powerful promoter used in this work the magnitude of the changes seen is typically only in the order of 2-fold, suggesting that regulatory factors exist which limit the potential increase in metabolic flux caused by these manipulations. Nevertheless, it is demonstrated that flux through a pathway to a plant secondary product can be elevated by means of genetic manipulation.

Angiolymphoid hyperplasia with eosinophilia associated with tetanus toxoid vaccination

Three cases of angiolymphoid hyperplasia with eosinophilia are reported at the site of tetanus toxoid vaccination. All presented as nodules on the upper arm, a known adverse effect of the vaccine following superficial inoculation. Histologically the nodules showed numerous small and medium sized vessels, some lined by hyperplastic endothelial cells with perivascular lymphocytic cuffing and an inflammatory infiltrate of plasma cells, eosinophils and scattered mast cells. Lymphoid follicles replete with germinal centres were identified in the dermis and subcutaneous tissue. Immunostaining revealed a polytypic lymphoplasmacytic infiltrate and a curious IgE reticulated pattern within the germinal centres, a feature described in both Kimura's disease and angiolymphoid hyperplasia. The present study suggests that atopic reaction to tetanus toxoid may be an aetiological factor in some cases of angiolymphoid hyperplasia.

Reporting cervical intra-epithelial neoplasia (CIN): intra- and interpathologist variation and factors associated with disagreement

Eight histopathologists, based at different hospitals, who had previously examined 100 consecutive colposcopic cervical biopsies were circulated with the results of the initial study. The slides were then 'reblinded' and re-examined by the pathologists who, as before, assigned them into one of six diagnostic categories. The degree of interpathologist agreement for the seven observers who returned usable responses was characterized by kappa statistics and compared to the corresponding figures for the same observers from the previous study. Although some of the observers showed significant alterations in their diagnostic practices there was persistent poor agreement for CIN 1 and 2, mediocre agreement for CIN 3 and excellent agreement for invasive carcinoma. Intra-observer agreement was consistently better than inter-observer agreement for each of the diagnostic categories. Significant differences were found among observers in the degree of intra-observer variability. The 20 cases in which there was most disagreement were re-examined by one of the authors who compared these with 20 biopsies which caused little disagreement. Disagreement was considered to be associated with florid papilloma-virus changes, basal cell hyperplasia and severe inflammation in varying combinations. On the basis of these findings we suggest changes in the terminology of CIN lesions.

The utility of intraoperative cholangiography with acute cholecystitis

An increasingly important subset of patients with biliary tract disease are those with acute cholecystitis. The indications for both routine or selective intraoperative cholangiography (IOC) during elective cholecystectomy may not be appropriate for this group. The utility of IOC in the presence of acute cholecystitis was examined. The medical records of 223 patients with histologically confirmed acute cholecystitis were reviewed. Clinical and laboratory criteria included age, sex, white blood cell count (WBC), serum bilirubin and alkaline phosphatase levels. In 52 (23%) patients, IOC was not attempted and was technically unsuccessful in 15 (7%) patients. IOC was successful in 156 (70%) patients and, of these, six (4%) had a false-positive examination. The remainder are divided into two groups. Group 1 (131 patients) had true-negative IOC, whereas Group 2 (19 patients) had true-positive IOC as evidenced by stone recovery upon surgical exploration. When comparing Group 2 with Group 1, the mean preoperative laboratory values are higher; these differences do not reach statistical significance. Further, within Group 2, five (26%) patients did not demonstrate any clinical or laboratory elevations suggestive of common duct pathology. Thus, in acute cholecystitis, laboratory criteria do not appear to discriminate between the presence or absence of choledocholithiasis. IOC is advocated as an integral component of the operative procedure.

Monoaminergic substances in the teleost brain: Catecholamine levels in male and female winter flounder,Pseudopleuronectes americanus Walbaum, associated with gonadal recrudescence

High performance liquid chromatography with electrochemical detection (HPLC-EC) was used to quantitate catecholamine (CA) levels in the winter flounder brain following perchloric acid extraction/alumina purification of CNS tissues. Greater concentrations of norepinephrine (NE) and dopamine (DA) were present in the hypothalamus compared with the CA levels in whole brain. A seasonal study of CA brain levels in reproductively active male and female flounder demonstrated that monoamine levels reach their maxima in October in association with the rapid increases in gonadosomatic index. When perchloric acid extracts of the teleost and rat hypothalamus were submitted to direct HPLC-EC analysis, without alumina purification of CA neurotransmitters, similar hypothalamic profiles were obtained indicating the presence of identifiable biogenic amine neurotransmitters substances including NE, DA and serotonin (5-HT).

The temperature sensitivity of the Sabin type 3 vaccine strain of poliovirus: molecular and structural effects of a mutation in the capsid protein VP3

The growth of the Sabin strain of type 3 poliovirus is reduced at high temperatures compared to that of its virulent precursor strain Leon. Recombinant viruses have been generated from infectious cDNA clones and demonstrate that the temperature-sensitive (ts) phenotype is mainly attributable to a difference in residue 91 of the virion protein VP3. Examination of non-ts mutants derived in vitro or in vivo reveals the existence of second site mutations some of which are clearly able to suppress the ts phenotype. The location of residue 91 of VP3, and of a number of candidate suppressor mutations, in the atomic structure of the virion suggests that the ts phenotype may result in destabilization of the particle and that the suppressors may function by stabilizing specific interfaces. It is not yet clear whether the ts phenotype is expressed at the level of the particle or in the form of defects in assembly or uncoating of the virion, or all three.

Membrane anchoring of heparan sulfate proteoglycans by phosphatidylinositol and kinetics of synthesis of peripheral and detergent-solubilized proteoglycans in Schwann cells

Previous studies have shown that Schwann cells synthesize both peripheral and integral hydrophobic cell surface heparan sulfate proteoglycans (HSPGs). The experiments reported here were undertaken to investigate the mode of attachment of these proteins to the cell surface and their potential interrelationship. The binding of the hydrophobic HSPGs to membranes appears to be via covalently linked phosphatidylinositol based on the observation that incubation of the detergent-solubilized protein with purified phosphatidylinositol-specific phospholipase C significantly reduces the ability of the HSPGs to associate with phospholipid vesicles in a reconstitution assay. The peripherally associated HSPGs were released from the cells by incubation in the presence of heparin (10 mg/ml), 10 mM phytic acid (inositol hexaphosphate), or 2 M NaCl. These treatments also solubilized basement membrane HSPGs synthesized by the Schwann cells. These data suggest that the peripheral HSPGs are bound to the surface by electrostatic interactions. The peripheral and hydrophobic HSPGs were identical in overall size, net charge, length of glycosaminoglycan chains, and patterns of N-sulfation. To determine whether the peripheral HSPGs were derived from the membrane-bound form by cleavage of the membrane anchor, we examined the kinetics of synthesis and degradation of the two forms of HSPGs. The results obtained indicated the existence of two pools of detergent-solubilized HSPG with fast (t1/2 = 6 h) and slow (t1/2 = 55 h) turnover kinetics. The data were consistent with a model in which the peripheral HSPGs were derived from the slowly turning over pool of detergent-solubilized HSPGs.

Observer variation in histopathological diagnosis and grading of cervical intraepithelial neoplasia

To assess the variability among histopathologists in diagnosing and grading cervical intraepithelial neoplasia eight experienced histopathologists based at different hospitals examined the same set of 100 consecutive colposcopic cervical biopsy specimens and assigned them into one of six diagnostic categories. These were normal squamous epithelium, non-neoplastic squamous proliferations, cervical intraepithelial neoplasia grades I, II, and III, and other. The histopathologists were given currently accepted criteria for diagnosing and grading cervical intraepithelial neoplasia and asked to mark their degree of confidence about their decision on a visual linear analogue scale provided. The degree of agreement between the histopathologists was characterised by kappa statistics, which showed an overall poor agreement (unweighted kappa 0.358). Agreement between observers was excellent for invasive lesions, moderately good for cervical intraepithelial neoplasia grade III, and poor for cervical intraepithelial neoplasia grades I and II (unweighted kappa 0.832, 0.496, 0.172, and 0.175, respectively); the kappa value for all grades of cervical intraepithelial neoplasia taken together was 0.660. The most important source of disagreement lay in the distinction of reactive squamous proliferations from cervical intraepithelial neoplasia grade I. The histopathologists were confident in diagnosing cervical intraepithelial neoplasia grade III and invasive carcinoma (other) but not as confident in diagnosing cervical intraepithelial neoplasia grades I and II and glandular atypia (other). Experienced histopathologists show considerable interobserver variability in grading cervical intraepithelial neoplasia and more importantly in distinguishing between reactive squamous proliferations and cervical intraepithelial neoplasia grade I. It is suggested that the three grade division of cervical intraepithelial neoplasia should be abandoned and a borderline category introduced that entails follow up without treatment.

Genetic basis of attenuation of the Sabin type 3 oral poliovirus vaccine

The poliovirus type 3 Sabin oral poliovirus vaccine strain P3/Leon/12a1b differs in nucleotide sequence from its neurovirulent progenitor P3/Leon/37 by just 10 point mutations. The contribution of each mutation to the attenuation phenotype of the vaccine strain was determined by the construction of a series of recombinant viruses from infectious cDNA clones. The neurovirulence testing of recombinant viruses indicated that the attenuation phenotype is determined by just two point mutations: a C to U in the noncoding region at position 472 and a C to U at nucleotide 2034 which results in a serine-to-phenylalanine amino acid substitution in the structural protein VP3.