Surveillance for lumpy skin disease and foot and mouth disease in the Kimberley, Western Australia

We quantified the sensitivity of surveillance for lumpy skin disease (LSD) and foot and mouth disease (FMD) in cattle in the Kimberley region of Western Australia. We monitored producer and veterinary activity with cattle for 3 years commencing January 2020. Each year, ~274,000 cattle of 685,540 present on 92 pastoral leases (stations) were consigned to other stations, live export or slaughter. Veterinarians examined 103,000 cattle on the stations, 177,000 prior to live export, and 10,000 prior to slaughter. Detection probabilities for the disease prior to transport or during veterinary procedures and inspections were elicited by survey of 17 veterinarians working in Northern Australia. The veterinarians estimated the probabilities that they would notice, recognise, and submit samples from clinical cases of LSD and FMD, given a 5% prevalence of clinical signs in the herd. We used scenario tree methodology to estimate monthly surveillance sensitivity of observations made by producers and by veterinarians during herd management visits, pre-export inspections, and ante-mortem inspections. Average monthly combined sensitivities were 0.49 for FMD and 0.37 for LSD. Sensitivity was high for both diseases during the dry season and low in the wet season. We estimated the confidence in freedom from the estimated surveillance sensitivity given one hypothetically infected herd, estimated probability of introduction, and prior confidence in freedom. This study provided assurance that the Kimberley is free of these diseases and that routine producer and veterinary interactions with cattle are adequate for the timely detection of the disease should they be introduced.

Comparative effectiveness of surgeon-performed transversus abdominis plane blocks and epidural catheters following open hernia repair with transversus abdominis release

PURPOSE

Recovery protocols aim to limit narcotic administration following ventral hernia repair (VHR). However, little is known about the contribution of a protocol's individual components on patient outcomes. We previously reported that surgeon-performed transversus abdominis plane block (TAP-block) is more effective than ultrasound-guided TAP-block following VHR. This study evaluates the effectiveness of two postoperative analgesia modalities: epidural catheter and surgeon-performed TAP-block following VHR performed with transversus abdominis release (TAR).

METHODS

A retrospective analysis was performed on data prospectively collected between 2012 and 2019. All patients undergoing open VHR with TAR performed by a single surgeon were identified. Parastomal hernia repairs and any patients receiving ultrasound-guided TAP blocks or paraspinal blocks were excluded. Primary outcome was length of stay (LOS) with secondary outcomes including pain scores, opioid requirements, and 30-day morbidity. Linear regression was used to model LOS.

RESULTS

One hundred thirty-five patients met inclusion criteria (63 epidural, 72 TAP-block). The majority (67.4%) of patients were modified ventral hernia working group grade 2. The only statistically significant difference in postoperative pain scores between the groups was on postoperative day 2 (TAP block 3.19 versus epidural 4.11, p = 0.0126). LOS was significantly shorter in the TAP block group (4.7 versus 6.2 days, p = 0.0023) as was time to regular diet (3.2 versus 4.7 days, p < 0.0001). After controlling for confounders, epidural was associated with increased LOS by 1.3 days (p = 0.0004).

CONCLUSION

Epidural use following VHR with TAR is associated with increased LOS and increased time to regular diet without reducing pain or opioid use when compared to surgeon-performed TAP block.

Elevated leptin levels are associated with excess gains in fat mass in girls, but not boys, with type 1 diabetes: longitudinal study during adolescence

Adolescents, in particular girls, with type 1 diabetes may gain excessive weight during puberty. We present the results of a longitudinal study aimed to determine the roles of leptin and insulin in changes in body composition in subjects with type 1 diabetes and controls. Forty-six children (23 boys) with type 1 diabetes and 40 controls (20 boys) were followed from 8-17 yr of age. Height, weight, and sc skinfolds were assessed every 6 months, and a blood sample taken for leptin determination. Throughout the age range, body mass index (mean +/- SEM) was greater by 1.45 +/- 0.69 kg/m(2) in girls and 1.46 +/- 0.55 kg/m(2) in boys with type 1 diabetes compared with control values. In girls with type 1 diabetes, this reflected greater percent body fat (3.2 +/- 1.0%; P = 0.002), whereas in boys it related to differences in fat-free mass. Both boys and girls with type 1 diabetes had higher leptin levels adjusted for percent body fat than controls; in the girls this was related to insulin dose (regression coefficient B = 0.006 +/- 0.003; P = 0.04) and greater gains in fat mass. Hyperinsulinemia and raised leptin levels are associated with gains in fat mass throughout puberty in girls, but not boys, with type 1 diabetes.

Longitudinal study of leptin concentrations during puberty: sex differences and relationship to changes in body composition

Leptin may have a role in the initiation of puberty and the regulation of subsequent weight gain, but this hypothesis has not been tested by longitudinal study. We report data from 40 normal children (20 boys and 20 girls) followed from 8-16 yr of age with hormone measurements and auxology every 6 months. Before the onset of puberty, leptin levels were similar in boys and girls: G1, mean (95% confidence interval), 2.63 (2.17-3.20) ng/mL; B1, 2.47 (2.08-2.94) ng/mL (P = 0.64) and increased with age in both sexes (B, 0.107 +/- 0.042; P = 0.02). With the onset of puberty, leptin levels increased in girls (B2-B5, P < 0.0005), but decreased in boys (G2-G5, P < 0.0005). Similar positive independent relationships were seen between leptin and fat mass in girls (B, 0.106 +/- 0.022; P < 0.0005) and boys (B, 0.121 +/- 0.020; P < 0.0005), and negative relationships were found with fat-free mass [girls: B, -1.104 +/- 0.381 (P < 0.005); boys: B, -1.288 +/- 0.217 (P < 0.0005)]. Girls gained more fat mass than boys, whereas boys gained more fat-free mass, and this explained the sex difference in leptin levels. Leptin levels correlated significantly with a large number of other hormones, but none was independent of changes in body composition. In girls, but not in boys, low leptin levels during prepuberty (B1) predicted subsequent gains in the percent body fat during puberty (r = -0.75; P = 0.005). The sexual dimorphism in leptin levels during puberty reflects differential changes in body composition. Prepubertal leptin levels in girls also predict gains in the percent body fat.

Cross-linked growth hormone dimers have enhanced biological activity

In this study we have investigated the effect on the bioactivity of pituitary-derived human growth hormone (hGH) and recombinant bovine (b) GH after the addition of various concentrations of the water soluble cross-linking agent 1-ethyl-3(3-dimethylaminopropyl) carbodiimide (EDC; 6.25-100 mg/ml). The biological activity of resulting cross-linked reactions were determined by its ability to promote incorporation of 35SO4(2-) into costal cartilage of hypopituitary Snell dwarf mice in vivo. Administration of EDC-treated hGH solutions resulted in a significant enhancement of hormone activity in vivo compared with non-cross-linked samples. A similar significant enhancement of bGH activity in vivo was also observed when solutions containing recombinant bGH were cross-linked using EDC. For both hGH and bGH the degree of enhancement appears to be dose-dependent for the concentration of EDC (6.25-100 mg/ml for hGH; 6.25-50 mg/ml for bGH) present in the cross-linking reactions. SDS-PAGE analysis of EDC cross-linked solutions containing hGH and bGH spiked with 125I-hGH and 125I-bGH respectively revealed that dimeric GH was the primary cross-linked component. Increasing the concentration of EDC in cross-linking reactions resulted in increased formation of dimeric hGH and bGH. There was a significant correlation between the amount of GH dimer present and the increase in biological activity, suggesting that GH dimers were responsible for the enhanced biological activity. This was confirmed by the enhanced biological activity of a purified preparation of EDC cross-linked dimeric hGH. In conclusion, covalently cross-linked GH dimers reported here have enhanced bioactivity in vivo. However, since naturally occurring GH dimers are known to have reduced biological activity, this work suggests that the structure of EDC cross-linked GH dimers differs fundamentally from that of native dimeric hGH.

Insulin-like growth factor (IGF)-I, -II and IGF binding protein-2 (IGFBP-2) in the plasma of children with Wilms' tumour

Insulin-like growth factors (IGF)-I, -II and IGF binding protein-2 (IGFBP-2) have been measured in plasma of children with Wilms' tumour. The mean levels for total serum IGF-I and -II were not significantly altered in Wilms' tumour as compared with normal control plasma. However, the chromatographic profiles for IGF-I and -II in these groups were different with regard to the presence of IGF binding proteins and high molecular weight forms of IGFs; the high molecular weight form (9-15 kD) of IGF-II was significantly reduced in Wilms' tumour. Levels of IGFBP-2 were substantially elevated in serum from Wilms' tumour patients (1025 +/- 112 ng/ml compared with 416 +/- 44 ng/ml in controls), and inversely correlated with the levels of high molecular weight forms of IGF-II. We suggest that IGFBP-2 measurements might be of value as a marker for monitoring this type of tumour, either as an adjunct to diagnosis or surveillance of tumour growth during therapy.

Laron-type dwarfism with apparently normal high affinity serum growth hormone-binding protein

OBJECTIVE

Normal serum contains a high affinity GH-binding protein, which appears to be identical with the extracellular domain of the GH receptor. It is normally absent from the serum of patients with Laron-type dwarfism. We wished in this study to define the serum GH-binding protein status of a family with Laron-type dwarfism.

DESIGN AND PATIENTS

We performed an open case study of an Asian family in which three sisters (aged 3 to 15 years) had the phenotype of Laron-type dwarfism. Sera from a fourth, unrelated girl with Laron-type dwarfism and subjects without endocrine disorders were used as control samples.

MEASUREMENTS

Laron-type dwarfism was confirmed by demonstration of elevated serum GH levels and low serum IGF-I levels on immunoassay, with serum IGF-I levels failing to rise during treatment with GH. Serum GH-binding proteins were characterized using gel chromatography on Sephacryl S-100HR following incubation of serum with 125I-GH, Scatchard analysis of ligand binding, and by polyacrylamide gel electrophoresis after covalent cross-linking to 125I-GH.

RESULTS

All members of the family had high affinity serum GH-binding protein activity similar in size, circulating levels and apparent affinity for GH to that of normal subjects. This contrasted with the very low serum GH-binding protein activity in the unrelated child with Laron-type dwarfism and previous reports of serum GH-binding protein levels in this disorder.

CONCLUSIONS

The affected patients may possess a novel biochemical defect which results in GH-resistance and reduced production of IGF-I in the presence of normal serum GH-binding protein levels.

Growth, body composition, hormonal and metabolic status in lambs treated long-term with growth hormone

The effect of long-term (10 weeks) treatment with growth hormone (GH) was investigated in twin lambs, one sibling being a control and the other treated with GH (0.1 mg/kg live weight per d). The lambs were fed on a concentrate-grass cube (9:1 w/w) diet at a daily rate of 40 g fresh weight/kg live weight. The average daily live-weight gain of the GH-treated lambs was 36% greater than that of the controls (307 v. 225 g/d, P less than 0.01). The carcass composition of the GH-treated lambs changed: fat content was decreased (P less than 0.01) and protein content was increased (P less than 0.05) when expressed relative to carcass dry matter. The absolute weights and the weights when expressed relative to fleece-free empty body of some muscles were significantly increased in GH-treated lambs. The mean retention times of both particulate- and liquid-phase components of the digesta were unchanged by GH treatment, when calculated for the rumen or for the entire gastrointestinal tract. The feed conversion ratio was significantly greater (P less than 0.01) in GH-treated lambs compared with controls. Nitrogen retained per g N intake was also significantly increased (P less than 0.05) by GH treatment. Plasma urea concentrations were decreased (P less than 0.05) and glucose concentrations were increased (P less than 0.01) in GH-treated lambs, whereas non-esterified fatty acid concentrations were unchanged. Plasma insulin and total insulin-like growth factor-1 concentrations progressively increased in GH-treated lambs as treatment time continued. They were significantly correlated after week 4 of treatment. Two types of hepatic GH-binding site were detected, with high and low affinities for GH. The capacities of both binding sites were significantly increased (P less than 0.05) in GH-treated lambs when expressed per unit microsomal protein but, when expressed per liver, only the capacity of the high-affinity site was increased.

Antigenicity and efficacy of authentic sequence recombinant human growth hormone (somatropin): first-year experience in the United Kingdom

Twenty-one children were treated for GH deficiency with authentic sequence biosynthetic human GH (somatropin), 60 micrograms/kg body weight, subcutaneously, three times weekly for 1 year or longer. The magnitude of growth response and rise in serum insulin-like growth factor I levels were similar to those expected from experience with pituitary GH and somatrem. Three patients developed serum antibodies to GH with a binding capacity greater than 0.02 mg/l, but in only one patient was the GH binding capacity greater than 1.0 mg/l and he showed no attenuation of growth response. Escherichia coli polypeptide antibodies did not rise significantly and no clinically important side-effects occurred. Somatropin is safe, effective and of low immunogenicity in the treatment of GH deficiency.

A monoclonal antibody to human insulin-like growth factor-I: characterization, use in radioimmunoassay and effect on the biological activities of the growth factor

A monoclonal antibody (BPL-M23) to insulin-like growth factor-I (IGF-I) was obtained following immunization of BALB/c mice with human IGF-I conjugated to ovalbumin. The affinity constant of BPL-M23 for IGF-I was 10.5 litres/nmol and the cross-reactivities of IGF-II, multiplication-stimulating activity III-2 and insulin were 0.8, 0.03 and less than 0.0001% respectively. Porcine, bovine, ovine and rabbit sera, but not rat or mouse sera, showed substantial reactivity with the antibody. Comparison of radioimmunoassay analyses of 54 human serum samples from normal subjects and acromegalic and GH-deficient patients using BPL-M23 and a polyclonal rabbit antiserum (R557A) to human IGF-I showed a high correlation, indicating the usefulness of the monoclonal antibody in radioimmunoassay. Monoclonal antibody BPL-M23 was capable of abolishing the sulphation, mitogenic and insulin-like activities of IGF-I in in-vitro bioassays, suggesting that these activities may rely upon the same receptor-binding site which is near to the antibody-binding site.

Insulin-like growth factor-I binding proteins in serum from the domestic fowl

This investigation describes the presence of insulin-like growth factor-I (IGF-I) binding proteins in chicken serum. Whole blood was collected from broiler chickens of 7-9 weeks of age and analysed for binding proteins after gel permeation chromatography under both neutral and acidic conditions, and by polyacrylamide gel electrophoresis in the presence of 12.5% sodium dodecyl sulphate (SDS-PAGE). When serum was chromatographed under neutral conditions, about 70% of the IGF-I immunoreactivity was associated with a large protein complex (Mr = 150,000) and 20-25% was associated with an intermediate-sized protein complex (Mr = 45,000). Up to 6% of the serum IGF-I immunoreactivity was eluted in a fraction which corresponded to an Mr of about 7500 and was presumably free IGF-I. Chromatography under acidic conditions dissociated the IGF-I/protein complexes and revealed the presence of an acid-stable binding protein (Mr = 50,000-60,000). After analysis of serum by SDS-PAGE, three monomeric IGF-I binding proteins (Mr = 28,800, 33,200 and 40,700) were detected. The largest monomer (Mr = 40,700) is probably the binding protein component of the intermediate-sized IGF-I/protein complex. The relationship between the other monomers and both the large IGF-I/protein complex and the acid-stable binding protein is not known. Although the pattern of binding proteins in chicken serum is similar to that observed in mammals, a major difference is the presence of up to 6% of the serum IGF-I immunoreactivity in an unbound form.

Potentiation of growth hormone activity in sheep using monoclonal antibodies

Monoclonal antibody OA11 was raised against ovine GH; its effects on GH activity were examined in a target species relevant for animal production in vivo. The monoclonal antibody was found to enhance the galactopoietic response to exogenous GH in adult lactating ewes and also to potentiate the diabetogenic activity of both exogenous and endogenous GH in ewe lambs. Thus it was shown that GH activity may be manipulated above its usual dose-response range in normal, intact animals of commercial importance via immunological means.

Insulin like growth factor-I, protein kinase-C, calcium and cyclic AMP: partners in the regulation of chondrocyte mitogenesis and metabolism

The possible role of protein kinase-C (PKC), calcium and cyclic AMP (cAMP) in mediating the metabolic and mitogenic effects of insulin-like growth factor-I (IGF-I) on chondrocytes was investigated using a PKC activator (phorbol ester 12,13-dibutyrate, PDBU), a PKC inhibitor (compound H7), a calcium channel blocker, (verapamil) and a cAMP analogue (dibutyryl cAMP). IGF-I and PDBU stimulated sulphate and thymidine incorporation by chondrocytes. Both of these effects were inhibited by compound H7. Verapamil inhibited IGF-I- and PDBU-stimulated sulphate incorporation, but contrastingly stimulated basal and enhanced IGF-I and PDBU stimulation of thymidine incorporation. Dibutyryl cAMP increased basal and IGF-I-stimulated sulphate incorporation but inhibited but inhibited both basal and IGF-I stimulation of thymidine incorporation. These results suggest a harmonic overlap between the activities of PKC and cAMP-dependent PKA enzyme systems, and calcium balance in the mitogenic and metabolic process of the chondrocyte.

Surface structure and RNA-protein interactions of foot-and-mouth disease virus

The surface structure of foot-and-mouth disease virus (FMDV) and the interaction of the individual capsid proteins with the virus RNA have been examined using modification reagents. By measuring the extent of modification of the lysine residues of intact and disrupted virus particles and the 12S protein subunit with Bolton & Hunter reagent it was found that 54% of the residues of VP1, 15% of the residues of VP2 and 37% of the residues of VP3, equivalent to five, two and four lysine residues respectively, are on the surface of the intact virus particle. Polypeptide VP4 was not modified in intact virus particles, indicating that it has no lysine residues on the surface of the virus. Modification with sodium metabisulphite, which causes a specific transamination reaction between cytidylic acid residues in ssRNA and closely associated basic amino acids, cross-linked all four structural proteins to the virus RNA. Both fragments of VP1, produced by treatment of the virus particle with trypsin, are also cross-linked to the RNA. These observations have been combined with the evidence that the immunogenic activity of VP1 may be contained in two discontinuous sites, at amino acids 141 to 160 and 200 to 213, in proposing a model for the arrangement of this polypeptide in the virus particle.

Somatomedin C/insulin-like growth factor I: simplified purification procedure and biological activities of the purified growth factor

Human somatomedin C has been purified from Cohn fraction IV paste by a simplified procedure using chromatofocusing, hydroxylapatite chromatography and reverse-phase high performance chromatography. The purified material has a specific activity by somatomedin C radioimmunoassay of 9160 units/mg (1 unit is defined as the amount of somatomedin present in 1 ml normal adult male human serum), representing a 650,000-fold purification, and possesses sulphation, mitogenic and insulin-like activities (specific activities of 3388 units/mg, 832 units insulin equivalents/mg and 1122 units/mg respectively). Somatomedin C is shown to be a potent stimulator of DNA synthesis (50% maximum stimulation at 150 fmol/ml) in isolated chondrocytes derived from costal cartilage, a major physiological target tissue.

Nature of the antibody response to the foot-and-mouth disease virus particle, its 12S protein subunit and the isolated immunizing polypeptide VP1

Inoculation of inactivated 146S foot-and-mouth disease virus particles into guinea-pigs elicited the formation of neutralizing antibody and the serum had a 10-fold higher titre in radioimmunoassay (RIA) with 146S particles than with the 12S virus subunit. In contrast, a single inoculation of the 12S subunit or the isolated polypeptide VP1 elicited the formation of antibody having a much lower titre in RIA with the 146S particle than with the 12S subunit and low or undetectable neutralizing activity. However, sera from guinea-pigs given two or more inoculations of the 12S subunit or VP1 had neutralizing activity. The level in the anti-VP1 serum was lower than that in the anti-12S serum and both were much lower than that in animals receiving two inoculations of the 146S particle. The neutralizing activity elicited by the three antigens was absorbed by the homologous antigen. In contrast, neither the 12S subunit nor VP1 absorbed the anti-146S neutralizing antibody and VP1 did not absorb the anti-12S subunit neutralizing antibody. However, the 12S subunit partly absorbed the neutralizing activity elicited by VP1. The results are compatible with a model in which the 146S particle elicits a spectrum of neutralizing antibodies which are completely absorbed by the homologous particle but only partially by the 12S subunit or VP1. The results are discussed in relation to the structural features required for the production of neutralizing antibody.