Radiopaque marker colonic transit study in the pediatric population BSPGHAN Motility Working Group consensus statement.

Functional constipation (FC) is a common condition in childhood in the United Kingdom and worldwide. Various radiological approaches have been established for diagnostic purposes. The radiopaque marker study (ROMS) is universally accepted and used to assess colonic transit time (CTT) in children with FC. Despite being widely used, there is a lack of standardization with various technical protocols, reproducibility of different populations, the purpose for using investigation, variance in the number of markers used, the amount of study days and calculations, the need to empty the colon before performing the test, and whether to perform on medication or off, or the use of specific diets. As part of the British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN) motility working group (MWG), we decided to explore further into the evidence, in order to provide guidance regarding the use of ROMS in dealing with FC in the pediatric population.

A recessive contiguous gene deletion causing infantile hyperinsulinism, enteropathy and deafness identifies the Usher type 1C gene.

Usher syndrome type 1 describes the association of profound, congenital sensorineural deafness, vestibular hypofunction and childhood onset retinitis pigmentosa. It is an autosomal recessive condition and is subdivided on the basis of linkage analysis into types 1A through 1E. Usher type 1C maps to the region containing the genes ABCC8 and KCNJ11 (encoding components of ATP-sensitive K + (KATP) channels), which may be mutated in patients with hyperinsulinism. We identified three individuals from two consanguineous families with severe hyperinsulinism, profound congenital sensorineural deafness, enteropathy and renal tubular dysfunction. The molecular basis of the disorder is a homozygous 122-kb deletion of 11p14-15, which includes part of ABCC8 and overlaps with the locus for Usher syndrome type 1C and DFNB18. The centromeric boundary of this deletion includes part of a gene shown to be mutated in families with type 1C Usher syndrome, and is hence assigned the name USH1C. The pattern of expression of the USH1C protein is consistent with the clinical features exhibited by individuals with the contiguous gene deletion and with isolated Usher type 1C.

Balance testing: does it make a difference?

OBJECTIVE: This study aimed to analyse whether referral for specialist balance testing influences diagnosis and management of patients with dizziness. METHOD: This was a retrospective study examining patients referred for vestibular function testing between 1 January 2018 and 30 June 2018. RESULTS: A total of 101 patients were referred, with 69 patients (68.3 per cent) receiving a preliminary 'pre-vestibular function testing balance diagnosis', which included benign paroxysmal positional vertigo (32.7 per cent), Ménière's disease (13.8 per cent) and migraine (14.9 per cent). Following vestibular function testing, revised diagnoses were achieved for 54 patients (53.5 per cent), including benign paroxysmal positional vertigo (14.9 per cent), Ménière's disease (3.0 per cent) and migraine (10.9 per cent). Pre-vestibular function testing balance diagnoses were confirmed for 32.4 per cent of patients. If no pre-vestibular function testing suspected diagnosis was provided, vestibular function testing was significantly more likely to be inconclusive. Following vestibular function testing, 38.6 per cent were discharged, 21.7 per cent were referred to another specialty and treatment was commenced for 17.8 per cent of patients. CONCLUSION: Referral for vestibular function testing has a role when attempting to answer a clear clinical question. Diagnosing the underlying aetiology of complex imbalance is challenging, but diagnosis can be assisted by judicious use of vestibular function testing.

Loss of functional KATP channels in pancreatic beta-cells causes persistent hyperinsulinemic hypoglycemia of infancy.

Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) is a disorder of childhood associated with inappropriate hypersecretion of insulin by the pancreas. The pathogenesis of the condition has hitherto remained controversial. We show here that insulin-secreting cells from a homogeneous group of five infants with PHHI lack ATP-sensitive K+ channel (KATP) activity. As a consequence, PHHI beta-cells are spontaneously electrically active with high basal cytosolic Ca2+ concentrations due to Ca2+ influx. Our findings define the pathogenesis of this disease as a novel K+ channel disorder.

Obstetric anesthesia management of the patient with cardiac disease.

Cardiovascular disease is the leading cause of maternal mortality in much of the developed world. Risk stratification models can predict which patients are at greatest risk for maternal or fetal morbidity or mortality. Particular cardiac diseases hold significant risk of mortality during pregnancy including pulmonary hypertension, aortic aneurysm, left-ventricular outflow tract obstruction, and severe cardiomyopathy. High-risk patients should deliver at high-resource hospitals under the care of experts in cardiology, obstetrics, perinatology, neonatology and anesthesiology. The obstetric anesthesiologist should formulate delivery plans for cardiac monitoring, labor analgesia, cesarean anesthesia, postpartum monitoring, as well as plans for obstetric or cardiac emergencies. Carefully co-ordinated multidisciplinary care of pregnant women with cardiac disease can result in successful outcomes.

Gastrointestinal complications of epidermolysis bullosa in children.

BACKGROUND: Epidermolysis bullosa (EB) is a group of inherited disorders characterized by skin and mucous membrane fragility. Gastrointestinal (GI) complications have been described in many types of EB and are responsible for significant morbidity. OBJECTIVES: To delineate the nature and frequency of GI complications in a large cohort of paediatric patients with EB and to postulate why some complications occur more commonly in some specific subtypes. METHODS: The case notes of 223 children with EB seen at a national referral centre were examined retrospectively for the presence of GI symptoms, investigations and interventions. RESULTS: GI complications were present in 130/223 (58%) of all patients. In EB simplex, constipation and gastro-oesophageal reflux (GOR) were frequently observed. In junctional EB, failure to thrive and protein-losing enteropathy (PLE) were the prominent GI manifestations. Constipation was common in patients with dystrophic EB (DEB) requiring laxatives and in some cases fibre supplementation. GOR affected three-quarters of those with recessive DEB, two-thirds also having significant oesophageal strictures. Over half of patients with recessive DEB required gastrostomy insertion. Diarrhoea affected a small but significant proportion of children with recessive DEB with macroscopic and/or microscopic changes of colitis in the majority. CONCLUSION: GI problems in EB are very common with subtype specificity for some of these complications. The occurrence of diarrhoea, PLE and colitis in the context of EB has not been highlighted previously, and may arise secondarily to antigenic exposure in the gut lumen as a result of mucosal fragility.

Gastric emptying is accelerated following laparoscopic Nissen fundoplication.

AIM OF THE STUDY: The effects on gastric motility following Nissen fundoplication in children are poorly documented. Some paediatric surgeons advocate additional procedures at the same time as fundoplication, such as a pyloroplasty, to enhance gastric emptying. The aim of this study was to determine whether laparoscopic Nissen fundoplication without pyloroplasty affects gastric emptying. METHODS: Gastric emptying was measured before laparoscopic Nissen fundoplication in 8 children after ingestion of a standardised volume of milk for age mixed with 150 mg of (13)C-octanoic acid. None of the patients had a gastrostomy insertion at the time of fundoplication and 2 patients had neurological impairment. Breath samples were collected by breathing into a mask at baseline and every 15 minutes up to 3 hours, and were analysed for (13)CO (2)/ (12)CO (2) ratio by mass spectrometry. Gastric emptying time (t (1/2)) was derived from the curve of (13)CO (2)/ (12)CO (2) ratio against time. The test was repeated in 6 children following Nissen fundoplication at the time of full feeds. Data are reported as mean +/- SD and were analysed by the Mann-Whitney test. RESULTS AND CONCLUSIONS: There were 4 males and 4 females; mean age at surgery was 3.3 +/- 3.0 years. Mean gastric emptying time was 59 +/- 17 min prior to laparoscopic Nissen fundoplication and 45 +/- 4 min following surgery (p = 0.03). Gastric emptying was accelerated in all except one patient. Gastric emptying for liquids is accelerated following Nissen fundoplication in children. Procedures aimed at improving gastric emptying time such as pyloroplasty or pyloromyotomy might not be justified at the time of laparoscopic Nissen fundoplication.

Therapy for persistent hyperinsulinemic hypoglycemia of infancy. Understanding the responsiveness of beta cells to diazoxide and somatostatin.

The neonatal disorder persistent hyperinsulinemic hypoglycemia of infancy (PHHI) arises as the result of mutations in the subunits that form the ATP-sensitive potassium (KATP) channel in pancreatic beta cells, leading to insulin hypersecretion. Diazoxide (a specific KATP channel agonist in normal beta cells) and somatostatin (octreotide) are the mainstay of medical treatment for the condition. To investigate the mechanism of action of these agents in PHHI beta cells that lack KATP currents, we applied patch clamp techniques to insulin-secreting cells isolated from seven patients with PHHI. Five patients showed favorable responses to medical therapy, and two were refractory. Our data reveal, in drug-responsive patients, that a novel ion channel is modulated by diazoxide and somatostatin, leading to termination of the spontaneous electrical events that underlie insulin hypersecretion. The drug-resistant patients, both of whom carried a mutation in one of the genes that encode KATP channel subunits, also lacked this novel K+ channel. There were no effects of diazoxide and somatostatin on beta cell function in vitro. These findings elucidate for the first time the mechanisms of action of diazoxide and somatostatin in infants with PHHI in whom KATP channels are absent, and provide a rationale for development of new therapeutic opportunities by K+ channel manipulation in PHHI treatment.

Topical application of mitomycin-C in oesophageal strictures.

BACKGROUND: Benign oesophageal strictures may occur as a complication of caustic ingestion or severe gastro-oesophageal reflux or as a sequela of oesophageal surgery and other fibrosing conditions. The traditional initial treatment of oesophageal strictures is intraluminal dilation; however, even if frequent, this occasionally may not provide adequate oesophageal lumen capacity or give significant symptom-free intervals, and restricturing after dilation is difficult and challenging. Topical postdilation application of an antifibrotic agent, mitomycin-C, in the treatment of an oesophageal stricture has been described. PATIENTS AND METHODS: Eight centres participated, with a total of 16 patients (4 girls), median age 48 (range 0-276) months. The causes of stricture were as follows: caustic (10), post-trachea-oesophageal fistula repair (2), peptic (2), Crohn disease (1), and dystrophic epidermolysis bullosa (1). The median (range) length and diameter of the strictures were as follows: 22 mm (8-50 mm) and 1.5 mm (1-6 mm). Of the 16 patients, 15 had undergone repeated dilations varying from 3 to more than 1000 (daily self-bouginage) before mitomycin-C, and the median interval between dilations was 4 weeks. Mitomycin-C 0.1 mg/mL was applied after dilation for a median time of 3.5 minutes and a median of 3 (1-12) times. RESULTS: Major success, both endoscopic and clinical improvement or cure, occurred in 10 of 16 patients. In 3 of 16 patients the interval period between dilations increased dramatically. Failure of therapy was considered in 3 of 16. All of the patients remained symptom free for a follow-up time of as long as 5 years. CONCLUSIONS: Postdilation application of topical mitomycin-C resulted in major success in 62.5% of patients and partial success in 19%, and it may be a useful strategy in oesophageal strictures of differing causes that are refractory to repeated perendoscopic dilation.

Sequential incremental doses of bisacodyl increase the diagnostic accuracy of colonic manometry.

BACKGROUND: Colonic manometry is the standard diagnostic modality for evaluating colonic motility in children. Intraluminal bisacodyl is routinely used to trigger high-amplitude propagating contractions (HAPCs), a feature of normal colonic motility. Usually, only a single dose (0.2 mg/kg) is suggested. We retrospectively explored whether the use of an additional higher (0.4 mg/kg) dose of bisacodyl increases the yield of colonic manometry. METHODS: In 103 children (median age: 8.8 years, range 3.2-15.7 years) with a diagnosis of slow transit constipation, colonic motility was recorded for 1 h before and 1 h after each of two incremental doses of bisacodyl (low, L, dose: 0.2 mg/kg, max 10 mg; high, H, dose: 0.4 mg/kg, max 20 mg) and the characteristics of HAPCs analyzed. KEY RESULTS: High-amplitude propagating contractions were seen in 85 children. H dose significantly increased the proportion of patients with fully propagated HAPCs (H dose: 57/103 [55%], L dose: 27/103 [26%], p < 0.001), paralleling the significant decrease in the proportion with partially propagated HAPCs (H dose: 29/103 [28%], L dose: 47/103 [46%], p < 0.01). Mean HAPC number significantly increased throughout the colon at H compared to L dose (7.2 ± 5.05 vs 5.6 ± 5.1, p < 0.05). Finally, the proportion of patients with normal pressure wave morphology of HAPCs significantly increased with higher dose (H dose: 55/85 [65%], L dose: 27/85 [32%], p < 0.001). CONCLUSIONS & INTERFERENCES: An additional higher dose of bisacodyl during colonic manometry improves colonic neuromuscular function suggesting its use might improve interpretation and decision making in children with slow transit constipation.

Hyperinsulinemic hypoglycemia in Beckwith-Wiedemann syndrome due to defects in the function of pancreatic beta-cell adenosine triphosphate-sensitive potassium channels.

BACKGROUND: Beckwith-Wiedemann syndrome (BWS) is a congenital overgrowth syndrome that is clinically and genetically heterogeneous. Hyperinsulinemic hypoglycemia occurs in about 50% of children with BWS and, in the majority of infants, it resolves spontaneously. However, in a small group of patients the hypoglycemia can be persistent and may require pancreatectomy. The mechanism of persistent hyperinsulinemic hypoglycemia in this group of patients is unclear. PATIENTS AND METHODS: Using patch-clamp techniques on pancreatic tissue obtained at the time of surgery, we investigated the electrophysiological properties of ATP-sensitive K(+) (K(ATP)) channels in pancreatic beta-cells in a patient with BWS and severe medically-unresponsive hyperinsulinemic hypoglycemia. RESULTS: Persistent hyperinsulinism was found to be caused by abnormalities in K(ATP) channels of the pancreatic beta-cell. Immunofluorescence studies using a SUR1 antibody revealed perinuclear pattern of staining in the BWS cells, suggesting a trafficking defect of the SUR1 protein. No mutations were found in the genes ABCC8 and KCNJ11 encoding for the two subunits, SUR1 and KIR6.2, respectively, of the K(ATP) channel. Genetic analysis of this patients BWS showed evidence of mosaic paternal isodisomy. CONCLUSIONS: In this novel case of BWS with mosaic paternal uniparental disomy for 11p15, persistent hyperinsulinism was due to abnormalities in K(ATP) channels of the pancreatic beta-cell. The mechanism/s by which mosaic paternal uniparental disomy for 11p15 causes a trafficking defect in the SUR1 protein of the K(ATP) channel remains to be elucidated.

p57(KIP2) expression in normal islet cells and in hyperinsulinism of infancy.

Most cases of hyperinsulinism of infancy (HI) are caused by mutations in either the sulfonylurea receptor-1 (SUR1) or the inward rectifying K(+) channel Kir6.2, two subunits of the beta-cell ATP-sensitive K(+) channel (K(ATP) channel). Histologically, HI can be divided into two major subtypes. The diffuse form is recessively inherited and involves all beta-cells within the pancreas. Focal HI consists of adenomatous hyperplasia within a limited region of the pancreas, and it is caused by somatic loss of heterozygosity (LOH), including maternal Ch11p15-ter in a beta-cell precursor carrying a germ-line mutation in the paternal allele of SUR1 or Kir6.2. Several imprinted genes are located within this chromosomal region, some of which, including p57(KIP2) and IGF-II, have been associated with the regulation of cell proliferation. Using double immunostaining, we examined p57(KIP2) expression in different islet cell types, in control pancreases from different developmental stages (n = 15), and in pancreases from patients with both diffuse (n = 4) and focal HI (n = 9). Using immunofluorescence and computerized image analysis, we quantified IGF-II expression in beta-cells from patients with focal HI (n = 8). Within the pancreas, p57(KIP2) was specifically localized to the endocrine portion. beta-Cells demonstrated the highest frequency of expression (34.9 +/- 2.7%) compared with approximately 1-3% in other cell types. The fraction of beta-cells expressing p57(KIP2) did not vary significantly during development. beta-Cells within the focal lesions did not express p57(KIP2), whereas IGF-II staining inside focal lesions was mildly increased compared with unaffected surrounding tissue. In conclusion, we demonstrate that p57(KIP2) is expressed and is paternally imprinted in human pancreatic beta-cells. Loss of expression in focal HI is caused by LOH and is associated with increased proliferation and increased IGF-II expression. Manipulation of p57(KIP2) expression in beta-cells may provide a mechanism by which proliferation can be modulated, and thus this gene is a potential therapeutic target for reversing the beta-cell failure observed in diabetes.

Sulfonylurea receptor 1 and Kir6.2 expression in the novel human insulin-secreting cell line NES2Y.

NES2Y is a proliferating human insulin-secreting cell line that we have derived from a patient with persistent hyperinsulinemic hypoglycemia of infancy. This disease is characterized by unregulated insulin release despite profound hypoglycemia. NES2Y cells, like beta-cells isolated from the patient of origin, lack functional ATP-sensitive potassium channels (KATP) and also carry a defect in the insulin gene-regulatory transcription factor PDX1. Here, we report that the NES2Y beta-cells that are transfected with the genes encoding the components of KATP channels in beta-cells, sulfonylurea receptor (SUR) 1 and Kir6.2, have operational KATP channels and show normal intracellular Ca2+ and secretory responses to glucose. However, these cells, designated NESK beta-cells, have impaired insulin gene transcription responses to glucose. NES2Y beta-cells that are transfected with either Kir6.2 or SUR1 alone do not express functional KATP channels and have impaired intracellular free Ca2+ concentration-signaling responses to depolarization-dependent beta-cell agonists. These findings document that in NES2Y beta-cells, coexpression of both subunits is critically required for fully operational KATP channels and KATP channel-dependent signaling events. This article further characterizes the properties of the novel human beta-cell line, NES2Y, and documents the usefulness of these cells in diabetes-related research.

Hyperinsulinism of infancy: the regulated release of insulin by KATP channel-independent pathways.

Hyperinsulinism of infancy (HI) is a congenital defect in the regulated release of insulin from pancreatic beta-cells. Here we describe stimulus-secretion coupling mechanisms in beta-cells and intact islets of Langerhans isolated from three patients with a novel SUR1 gene defect. 2154+3 A to G SUR1 (GenBank accession number L78207) is the first report of familial HI among nonconsanguineous Caucasians identified in the U.K. Using patch-clamp methodologies, we have shown that this mutation is associated with both a decrease in the number of operational ATP-sensitive K+ channels (KATP channels) in beta-cells and impaired ADP-dependent regulation. There were no apparent defects in the regulation of Ca2+- and voltage-gated K+ channels or delayed rectifier K+ channels. Intact HI beta-cells were spontaneously electrically active and generating Ca2+ action currents that were largely insensitive to diazoxide and somatostatin. As a consequence, when intact HI islets were challenged with glucose and tolbutamide, there was no rise in intracellular free calcium ion concentration ([Ca2+]i) over basal values. Capacitance measurements used to monitor exocytosis in control and HI beta-cells revealed that there were no defects in Ca2+-dependent exocytotic events. Finally, insulin release studies documented that whereas tolbutamide failed to cause insulin secretion as a consequence of impaired [Ca2+]i signaling, glucose readily promoted insulin release. Glucose was also found to augment the actions of protein kinase C- and protein kinase A-dependent agonists in the absence of extracellular Ca2+. These findings document the relationship between SUR1 gene defects and insulin secretion in vivo and in vitro and describe for the first time KATP channel-independent pathways of regulated insulin secretion in diseased human beta-cells.

A new method to estimate catheter length for esophageal multichannel intraluminal impedance monitoring in children.

BACKGROUND: Multichannel intraluminal impedance combined with pH (MII-pH) is the gold standard test for diagnosing gastro-esophageal reflux disease (GERD). It provides an opportunity to study acid and non-acid GOR and temporal association between symptoms and reflux. Accurate catheter placement is essential to prevent erroneous recording of reflux events. The aims of our study were to assess the accuracy of our devised method in predicting the catheter length for MII-pH in children (Great Ormond Street Hospital (GOSH) Table) and to compare the results with Strobel and Monreau methods. METHODS: Retrospective review of all records of infants and children who underwent MII-pH studies between January to October 2014. Desired catheter position was calculated using Strobel, Monreau and GOSH formulas and compared to X ray position. KEY RESULTS: One hundred and forty-four children were included; mean age was 5.1 (±4.5) years, 73 males and 71 females. In the whole group, the correlation between desired catheter position and GOSH Table was 0.95, for Strobel was 0.84, and Monreau was 0.85. In the first group (age <3 years), the correlation was: GOSH Table 0.91, Strobel 0.56, and Monreau 0.6; in the second group (3-10 years): GOSH Table 0.78, Strobel 0.82, and Monreau 0.82; the third group (>10 years): GOSH 0.81, Strobel 0.43, and Monreau 0.43. CONCLUSIONS & INFERENCES: GOSH Table is an accurate method to estimate the insertion length of MII-pH catheters from nares to a point of approximately two vertebral bodies above the diaphragm in children. Although radiography is required to confirm final catheter position, using GOSH Table will reduce the need for repeated catheter manipulation after initial insertion and will reduce the use of a mathematically complicated formulae.

Uncontrolled insulin secretion from a childhood pancreatic beta-cell adenoma is not due to the functional loss of ATP-sensitive potassium channels.

We report the case of an 8-year-old child who presented with severe hyperinsulinaemic hypoglycaemia due to a pancreatic islet cell adenoma. In vivo, there was no beneficial response to the hyperglycaemia-inducing agent diazoxide and as a consequence the child underwent a subtotal pancreatectomy. In vitro studies of adenomatous beta-cells revealed no operational defects in ATP-sensitive potassium channel activity and appropriate responses to diazoxide. In comparison with patients with focal adenomatous hyperplasia, genetic analysis of the isolated adenoma showed no loss of heterozygosity for chromosome 11p15 and expression of the cyclin-dependent kinase inhibitor p57(kip2). This case illustrates that the excess insulin secretion from an infantile adenoma has an aetiology different from that observed in hyperinsulinism in infancy.

Production of monoclonal antibodies using recombinant baculovirus displaying gp64-fusion proteins.

Generation of protein immunogens is often a rate-limiting step in the production of monoclonal antibodies (Mabs). Expressing domains of proteins as fusions to the baculovirus surface glycoprotein gp64 displays foreign proteins on the surface of the virion. Antigen is produced by inserting a gene fragment in-frame between the signal sequence and the mature protein domain of the gp64 nucleotide sequence. This method allows immunization with whole virus, eliminating the need for purification of target antigens. Affinity-matured Mabs to the human nuclear receptors LXRbeta and FXR have been produced using baculovirus particles displaying gp64/nuclear receptor fusion proteins as the immunizing agent. Immunizations were performed directly with pelleted virus using the Repetitive Immunization Multiple Sites (RIMMS) immunization strategy for rapid Mab production. All Mabs were identified using insect cells infected with the immunizing virus. Characterization of these antibodies shows them to be class-switched and specific for LXRbeta or FXR. Additionally, high affinity antibodies that recognize gp64 and neutralize baculovirus infection of insect cells were isolated. Use of the recombinant baculovirus gp64 display system makes possible the production of Mabs once a partial DNA sequence is known. This allows the generation of antibodies prior to the isolation of purified protein, in turn providing antibodies to facilitate purification, characterization and immunolocalization of proteins.

Practical management of hyperinsulinism in infancy.

Hyperinsulinism in infancy is one of the most difficult problems to manage in contemporary paediatric endocrinology. Although the diagnosis can usually be achieved without difficulty, it presents the paediatrician with formidable day to day management problems. Despite recent advances in understanding the pathophysiology of hyperinsulinism, the neurological outcome remains poor, and there is often a choice of unsatisfactory treatments, with life long sequelae for the child and his or her family. This paper presents a state of the art overview on management derived from a consensus workshop held by the European network for research into hyperinsulinism (ENRHI). The consensus is presented as an educational aid for paediatricians and children's nurses. It offers a practical guide to management based on the most up to date knowledge. It presents a proposed management cascade and focuses on the clinical recognition of the disease, the immediate steps that should be taken to stabilise the infant during diagnostic investigations, and the principles of definitive treatment.

Detection of superficial zone protein in human and animal body fluids by cross-species monoclonal antibodies specific to superficial zone protein.

In this report we describe the purification of human superficial zone protein (SZP), the generation of cross-species monoclonal antibodies (MAbs) and the detection of this protein in human and animal body fluids. Human SZPs, used as immunizing antigens, were purified either from culture media of human cartilage organ cultures or from human synovial fluids. The immunizing antigens were mixed with RIBI adjuvant in one of three forms: nonmodified SZP, superficial zone protein-keyhole limpet hemocyanin conjugate (SZP-KLH), or a mixture of superficial zone protein and hyaluronic acid (SZP-HA). A panel of MAbs including GW4.23, S6.79, S13.52, S13.233, and S17.109 were generated and characterized. Monoclonal antibody (MAb) S6.79, an IgG2b with K(D) 3.14 x 10(-9) M from SZP-KLH immunization, is of particular interest. It reacts strongly to a large molecular weight form of SZP in both enzyme-linked immunosorbent assay (ELISA) and Western blotting. It stains the most superficial layer of articular cartilage in immunohistochemistry, whereas the middle and deep zones of cartilage are not stained. When MAb S6.79 was applied to Western blots of human body fluids, a strong 345-kDa band was detected in samples of synovial fluid and weaker bands of similar size were detected in samples of plasma and serum. MAb S6.79 also showed cross-species immunoreactivity with SZP in samples of synovial fluids harvested from bovine, dog, guinea pig, and rabbit, as demonstrated by Western blotting and antibody absorption experiments. This cross-species MAb will be a useful tool in human and animal model studies for monitoring SZP levels and tissue distribution. It may help define the roles of SZP in normal articular joints and may be of diagnostic or prognostic value for the measurement of SZP in pathological conditions such as osteoarthritis, rheumatoid arthritis, and camptodactyly-arthropathy-coxa vara-pericarditis.

Serum zinc, selenium and copper concentration in children with allergic colitis.

Children with allergic colitis have low levels of zinc and selenium which is partly a reflection of their low albumin levels and/or increased utilization of zinc and selenium as antioxidants as a result of the inflammatory process.