Evaluation of the performance of a lateral flow device for quantitative detection of anti-SARS-CoV-2 IgG.

INTRODUCTION: The AbC-19™ lateral flow immunoassay (LFIA) performance was evaluated on plasma samples from a SARS-CoV-2 vaccination cohort, WHO international standards for anti-SARS-CoV-2 IgG (human), individuals ≥2 weeks from infection of RT-PCR confirmed SARS-CoV-2 genetic variants, as well as microorganism serology. METHODS: Pre-vaccination to three weeks post-booster samples were collected from a cohort of 111 patients (including clinically extremely vulnerable patients) from Northern Ireland. All patients received Oxford-AstraZeneca COVID-19 vaccination for the first and second dose, and Pfizer-BioNTech for the third (first booster). WHO international standards, 15 samples from 2 variants of concern (Delta and Omicron) and cross-reactivity with plasma samples from other microorganism infections were also assessed on AbC-19™. RESULTS: All 80 (100%) participants sampled post-booster had high positive IgG responses, compared to 38/95 (40%) participants at 6 months post-first vaccination. WHO standard results correlated with information from corresponding biological data sheets, and antibodies to all genetic variants were detected by LFIA. No cross-reactivity was found with exception of one (of five) Dengue virus samples. CONCLUSION: These findings suggest BNT162b2 booster vaccination enhanced humoral immunity to SARS-CoV-2 from pre-booster levels, and that this antibody response was detectable by the LFIA. In combination with cross-reactivity, standards and genetic variant results would suggest LFIA may be a cost-effective measure to assess SARS-CoV-2 antibody status.

Effects of aggregation and sample size on composite faecal egg counts in sheep.

Composite faecal egg counts (FEC) are increasingly used to support strategic anthelmintic treatment decisions in grazing livestock. However, their accuracy as estimators of group mean FEC is affected by the number of individual samples included, how thoroughly they are mixed, and the underlying degree of parasite aggregation between individual hosts. This paper uses a Negative Binomial model for parasite aggregation, and a Poisson model for egg distribution within faecal suspensions, in order to optimise composite FEC protocol for commercial sheep flocks. Our results suggest that faecal egg density in a well-mixed composite sample from 10 sheep (3g of faeces from each), estimated by examination of four independently filled McMaster chambers, is likely to provide an adequate estimate of group mean FEC in the majority of situations. However, extra care is needed in groups of sheep for which high levels of FEC aggregation might be expected. The implications of statistical error in FEC estimates depend on how they are used. The simulation-based approach presented here is a powerful tool for investigating the risks of error in FEC-driven treatment decisions in different situations, as well as for the statistical analysis of parasitological data in general.

Treatment for a severe reaction to intravenous administration of diatrizoate in an anesthetized horse.

A mature horse developed acute signs of bronchoconstriction causing hypoxemia and hypercapnia during anesthesia for computerized tomography of the maxillary sinus after i.v. administration of diatrizoate contrast medium. The horse was treated with aerosolized albuterol, atropine, and oxygen insufflation and recovered uneventfully despite severe hypoxemia and low hemoglobin saturation. The horse's condition continued to improve after treatment, and the horse was discharged with no further complications. Caution is advised with the use of contrast media in anesthetized horses.

Pythiosis in a dromedary camel (Camelus dromedarius).

A 4.5-yr-old male dromedary camel (Camelus dromedarius) was evaluated for a mass on the right side of the face. A complete blood count and blood chemistry revealed anemia and hypoproteinemia. Radiographs did not reveal bony involvement. The mass was resected and Pythium insidiosum was cultured. The camel was treated with an experimental immunotherapeutic vaccine and with sodium iodide and ceftiofur. The camel began to lose weight postoperatively and died 6 mo later. At necropsy, the camel was found to have gastritis of the third compartment of the stomach with intralesional hyphae of this oomycete pathogen.

Hand-assisted laparoscopic left nephrectomy in standing horses.

OBJECTIVE: To describe a hand-assisted, laparoscopic technique to remove the left kidney in standing horses. STUDY DESIGN: Prospective evaluation. ANIMALS: Eight horses. METHODS: Food was withheld for a minimum of 12 hours. Horses were sedated with detomidine hydrochloride (0.01-0.02 mg/kg, intravenously) and restrained in standing stocks. The left paralumbar fossa was prepared for surgery, and the surgical site was infiltrated with 2% mepivacaine. Hand-assisted, laparoscopic removal of the left kidney was performed through an incision in the center of the paralumbar fossa; the surgeon's hand was used to isolate the left kidney and associated vasculature. The renal artery and vein were isolated and individually ligated. After vessel transection distal to the ligatures, the left kidney was exteriorized, the ureter ligated and transected, and the incision closed. RESULTS: Laparoscopic removal of the left kidney was successfully performed in all horses. Retroperitoneal infiltration of local anesthesia provided adequate anesthesia. Intraoperative hemorrhage occurred in 3 horses. Surgical duration (initial skin incision to transection of the left kidney) ranged from 20 to 90 minutes. In 2 horses, no signs of pain were noted for 48 hours postoperatively. CONCLUSION: Hand-assisted laparoscopic surgery can be used for removal of the left kidney in horses. Clinical Relevance-Hand-assisted laparoscopic nephrectomy can be safely performed in standing horses; however, care should be taken to identify accessory branches of the renal artery to limit potential complications with hemorrhage.

The role of iron and haemochromatosis gene mutations in the progression of liver disease in chronic hepatitis C.

BACKGROUND: Chronic hepatitis C virus (HCV) infection is frequently associated with elevated markers of iron stores. Recessively inherited mutations in the HFE gene are responsible for iron accumulation in most cases of hereditary haemochromatosis and may have a role in HCV infection. They may also be associated with progressive liver fibrosis although this remains controversial. AIMS: To assess the prevalence of HFE mutations in Scottish HCV infected patients and to explore the effect of the carrier state on serum and liver iron stores, and the severity of liver disease. PATIENTS: A total of 164 patients with antibodies to HCV who underwent liver biopsy were assessed prospectively. METHODS: Each patient was screened for HFE mutations (Cys282Tyr and His63Asp). Iron markers were assessed in serum (ferritin, transferrin saturation) and on liver biopsy (stainable iron, liver iron concentration (LIC) and hepatic iron index). RESULTS: There were 67 (41%, 26 Cys282Tyr, 33 His63Asp, eight compound) heterozygotes. Forty four (28%) patients had elevated serum iron markers, 24 (15%) had stainable liver iron, and five (3%) had elevated LICs. Carriage of HFE mutations was not associated with any clinical, biochemical, virological, or pathological features, including accumulation of liver iron. Elevated serum iron markers were associated with male sex, increased alcohol consumption, and increased liver inflammation and fibrosis. Patients with elevated LICs were older, acquired HCV infection earlier, and had more liver inflammation. CONCLUSIONS: Patients with chronic HCV infection frequently have elevated serum iron markers although elevated LICs are uncommon. Elevated serum iron studies and LICs occur in patients with more severe liver disease. Carriage of HFE mutations, although frequently observed in these HCV infected patients, does not have a role in the accumulation of iron or the progression of liver disease in HCV infection.

Prevalence and treatment of pressure ulcers in northern New South Wales.

This paper reports on a small, cross-sectional study of 18 hospitals in northern New South Wales. The objectives of this study were to collect baseline data on: (i) the prevalence and type of pressure ulcers in a variety of rural hospitals; and (ii) the range of nursing and medical interventions that are used to prevent/treat pressure ulcers. Using a cross-sectional design, the study found that pressure ulcer prevalence, which was 6%, was within the range found by previous reports (4-15%). Pressure ulcer prevention and treatment practices were varied, ranging from turning of the patient and occlusive dressings, to such creative methods as exposure to sunshine and airing the wound. This study demonstrates that despite years of attention to pressure sore prevention and treatment, the prevalence of ulcers is still a significant problem in northern New South, Wales hospitals.

Ethnic affinities of the ancient human Jety-Asar population by mitochondrial DNA analysis.

An anthropological study of the remains has indicated uniformity of the ancient human Jety-Asar population (Central Asia) and suggests a mixed Euro-Mongoloid genesis. DNA was extracted from teeth from three Caucasoid skulls recovered from a burial site dated at approximately 2000 years ago. Ancient mitochondrial DNA (mtDNA) was analysed by restriction fragment length polymorphism (RFLP) analysis for the A, B, C and D haplogroups and the sequencing of hypervariable region I of the mtDNA control region. The full set of mtDNA control region variants determined for Jety-Asar specimens was only found among a modern Mongolian population (Mongoloid people), indicating some discordance of molecular and morphological data.

Advances in cubicle design using computational fluid dynamics as a design tool.

As part of a recent animal facility refurbishment, a cubicle containment system was designed to increase the amount of experimental space and also provide containment facilities to support the holding and use of specialized animal models. In order to achieve this, a series of computational fluid dynamic (CFD) studies was undertaken to evaluate the effects of different airflows and in order to optimize ventilation, a variety of exhaust/supply arrangements and animal loads was employed. These studies showed that air delivered via two, opposed, low level ducts, at a rate of 20 air changes per hour and exhausted high in the cubicle above the rack, was the optimal configuration resulting in minimal turbulence, stagnation and entrainment.

Migration and circulation as a way of life for the Wosera Abelam of Papua New Guinea.

"Migration and circulation are now an integral part of the socio-economy of the Wosera Abelam of Papua New Guinea. Since the 1950s large numbers of Wosera Abelam have settled in West New Britain (WNB) towns and government sponsored resettlement schemes.... This paper explores the linkages between temporary and long-term migrants in WNB, and between migrants and their relatives remaining in the village. We argue that migration is now a ¿way of life' for the Wosera Abelam, and is, to a large extent, underpinned by indigenous (precapitalist) social and economic relations."

The Lancashire telemedicine ambulance.

An emergency ambulance was equipped with three video-cameras and a system for transmitting slow-scan video-pictures through a cellular telephone link to a hospital accident and emergency department. Video-pictures were trasmitted at a resolution of 320 x 240 pixels and a frame rate of 15 pictures/min. In addition, a helmet-mounted camera was used with a wireless transmission link to the ambulance and thence the hospital. Speech was transmitted by a second hand-held cellular telephone. The equipment was installed in 1996-7 and video-recordings of actual ambulance journeys were made in July 1997. The technical feasibility of the telemedicine ambulance has been demonstrated and further clinical assessment is now in progress.

Pathogenesis of primary hepatocellular carcinoma.

Primary hepatocellular carcinoma (HCC) is a major cause of mortality world-wide, with a poorly understood pathogenesis. We review known aetiological factors and the mechanisms whereby they are associated with the development of hepatocellular carcinoma. The increasing knowledge of the dysregulation of cellular growth control that occurs during HCC development is discussed in detail.

Gastric mucosal hepatocyte growth factor in Helicobacter pylori gastritis and peptic ulcer disease.

OBJECTIVES: Hepatocyte growth factor (HGF) is increasingly recognized for its role in a variety of hepatic and systemic diseases. Its relationship to gastritis has not been studied. We aimed at measuring gastric mucosal HGF levels in the presence or absence of Helicobacter pylori gastritis, in peptic ulcers, and in response to H. pylori eradication. METHODS: Fifty one patients were studied. Patients were not entered if they had liver disease, malignancy, or any systemic illness. HGF was measured in gastric antral incubates using an enzyme-linked immunosorbent assay. Assessments were repeated 6 wk after a 2-wk course of anti-H. pylori triple therapy in 12 patients. Code numbers were used for blinding. RESULTS: The median gastric mucosal HGF level was 36 ng/gm/tissue in patients with H. pylori gastritis (n = 33) compared with 19 ng/gm in 18 negative controls (p = 0.0024), 18 ng/gm after the eradication of H. pylori (p = 0.021), 23 ng/gm in all patients with ulcers (n = 10), and 26 ng/gm/tissue in H. pylori-positive ulcers (n = 7). CONCLUSIONS: Gastric mucosal HGF levels were elevated in H. pylori gastritis and reduced by its eradication. These results are relevant to our understanding of the increased gastric cell proliferation in patients with H. pylori-related gastritis.

Hepatocyte growth factor/scatter factor expression and c-met in primary breast cancer.

Hepatocyte growth factor/scatter factor (HGF/SF) is a fibroblast-derived cytokine whose receptor is encoded by c-met. Activation of c-met promotes tumour cell proliferation, dissociation, invasiveness and angiogenesis. Aberrant expression of HGF/SF or c-met may play a role in tumour progression. HGF/SF and c-met were determined in 73 breast cancers (median follow up: 61 months) and 10 samples of tumour-free breast tissue. HGF/SF was detected at significantly higher concentrations in breast cancers (median 350, range 58-1604 ng per 100 mg total protein) when compared with normal breast tissue (median 108, range 66-213 ng per 100 mg total protein) (P < 0.001). C-met was detected in all 10 samples of tumour-free breast tissue and in 26 breast cancers. HGF/SF concentrations correlated with disease relapse (P < 0.001) and reduced overall survival (P < 0.001). Tumours with detectable c-met correlated significantly with disease-relapse (P = 0.012). Multivariate analysis demonstrated a significant interaction between HGF/SF and c-met in relation to disease-relapse (P = 0.014). These results suggest a biological interaction involving HGF/SF and c-met in promoting tumour progression in breast cancer.