Production, Titration, Neutralisation, Storage and Lyophilisation of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Lentiviral Pseudotypes

This protocol details a rapid and reliable method for the production and titration of high-titre viral pseudotype particles with the SARS-CoV-2 spike protein (and D614G or other variants of concern, VOC) on a lentiviral vector core, and use for neutralisation assays in target cells expressing angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2). It additionally provides detailed instructions on substituting in new spike variants via gene cloning, lyophilisation and storage/shipping considerations for wide deployment potential. Results obtained with this protocol show that SARS-CoV-2 pseudotypes can be produced at equivalent titres to SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV) pseudotypes, neutralised by human convalescent plasma and monoclonal antibodies, and stored at a range of laboratory temperatures and lyophilised for distribution and subsequent application.

A super-potent tetramerized ACE2 protein displays enhanced neutralization of SARS-CoV-2 virus infection

Approaches are needed for therapy of the severe acute respiratory syndrome from SARS-CoV-2 coronavirus (COVID-19). Interfering with the interaction of viral antigens with the angiotensin converting enzyme 2 (ACE-2) receptor is a promising strategy by blocking the infection of the coronaviruses into human cells. We have implemented a novel protein engineering technology to produce a super-potent tetravalent form of ACE2, coupled to the human immunoglobulin γ1 Fc region, using a self-assembling, tetramerization domain from p53 protein. This high molecular weight Quad protein (ACE2-Fc-TD) retains binding to the SARS-CoV-2 receptor binding spike protein and can form a complex with the spike protein plus anti-viral antibodies. The ACE2-Fc-TD acts as a powerful decoy protein that out-performs soluble monomeric and dimeric ACE2 proteins and blocks both SARS-CoV-2 pseudovirus and SARS-CoV-2 virus infection with greatly enhanced efficacy. The ACE2 tetrameric protein complex promise to be important for development as decoy therapeutic proteins against COVID-19. In contrast to monoclonal antibodies, ACE2 decoy is unlikely to be affected by mutations in SARS-CoV-2 that are beginning to appear in variant forms. In addition, ACE2 multimeric proteins will be available as therapeutic proteins should new coronaviruses appear in the future because these are likely to interact with ACE2 receptor.

Implementing a method for engineering multivalency to substantially enhance binding of clinical trial anti-SARS-CoV-2 antibodies to wildtype spike and variants of concern proteins

Infection by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes COVID-19 disease. Therapeutic antibodies are being developed that interact with the viral spike proteins to limit viral infection of epithelium. We have applied a method to dramatically improve the performance of anti-SARS-CoV-2 antibodies by enhancing avidity through multimerization using simple engineering to yield tetrameric antibodies. We have re-engineered six anti-SARS-CoV-2 antibodies using the human p53 tetramerization domain, including three clinical trials antibodies casirivimab, imdevimab and etesevimab. The method yields tetrameric antibodies, termed quads, that retain efficient binding to the SARS-CoV-2 spike protein, show up to two orders of magnitude enhancement in neutralization of pseudovirus infection and retain potent interaction with virus variant of concern spike proteins. The tetramerization method is simple, general and its application is a powerful methodological development for SARS-CoV-2 antibodies that are currently in pre-clinical and clinical investigation.

Tissue Plasminogen Activator-Induced Angioedema Involving a Posterior Cerebral Artery Infarct: A Case Presentation

Patient: Female, 84-year-old

Final Diagnosis: Angioedema

Symptoms: Angioedema

Medication:—

Clinical Procedure: —

Specialty: Critical Care Medicine • General and Internal Medicine

Tracking SARS-CoV-2 in Sewage: Evidence of Changes in Virus Variant Predominance during COVID-19 Pandemic

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), responsible for the ongoing coronavirus disease (COVID-19) pandemic, is frequently shed in faeces during infection, and viral RNA has recently been detected in sewage in some countries. We have investigated the presence of SARS-CoV-2 RNA in wastewater samples from South-East England between 14th January and 12th May 2020. A novel nested RT-PCR approach targeting five different regions of the viral genome improved the sensitivity of RT-qPCR assays and generated nucleotide sequences at sites with known sequence polymorphisms among SARS-CoV-2 isolates. We were able to detect co-circulating virus variants, some specifically prevalent in England, and to identify changes in viral RNA sequences with time consistent with the recently reported increasing global dominance of Spike protein G614 pandemic variant. Low levels of viral RNA were detected in a sample from 11th February, 3 days before the first case was reported in the sewage plant catchment area. SARS-CoV-2 RNA concentration increased in March and April, and a sharp reduction was observed in May, showing the effects of lockdown measures. We conclude that viral RNA sequences found in sewage closely resemble those from clinical samples and that environmental surveillance can be used to monitor SARS-CoV-2 transmission, tracing virus variants and detecting virus importations.

Impact of coronavirus disease 2019 on urgent referrals to secondary care otolaryngology: a prospective case series

OBJECTIVE

As the novel coronavirus disease 2019 changed patient presentation, this study aimed to prospectively identify these changes in a single ENT centre.

DESIGN

A seven-week prospective case series was conducted of urgently referred patients from primary care and accident and emergency department.

RESULTS

There was a total of 133 referrals. Referral rates fell by 93 per cent over seven weeks, from a mean of 5.4 to 0.4 per day. Reductions were seen in referrals from both primary care (89 per cent) and the accident and emergency department (93 per cent). Presentations of otitis externa and epistaxis fell by 83 per cent, and presentations of glandular fever, tonsillitis and peritonsillar abscess fell by 67 per cent.

CONCLUSION

Coronavirus disease 2019 has greatly reduced the number of referrals into secondary care ENT. The cause for this reduction is likely to be due to patients' increased perceived risk of the virus presence in a medical setting. The impact of this reduction is yet to be ascertained, but will likely result in a substantial increase in emergency pressures once the lockdown is lifted and the general public's perception of the coronavirus disease 2019 risk reduces.

Effect of attire on client perceptions of veterinarians

This study examined the effect that veterinarian attire and gender had on clients' perceptions of veterinarians in a large academic specialty hospital. Clients volunteered to answer a survey in the small animal waiting area over a 3-month period. The survey consisted of demographic information, information about the nature of their appointment with their pet, and questions regarding clients' levels of comfort with and the perceived trustworthiness of a Caucasian male and Caucasian female model in four different types of attire: surgical scrubs, surgical scrubs with white lab coat, business casual, and business casual with white lab coat. Relevant effects of interest were estimated using linear mixed models. Five hundred and five clients participated in the survey, yielding a total of 6217 completed survey questions. Clients perceived veterinarians wearing white lab coats as more competent and reported more comfort with those veterinarians (P < 0.0001). When comparing surgical scrubs with no white lab coat to business attire with no white lab coat, surgical scrubs resulted in higher perceived competence and comfort levels (P < 0.0001). Wearing a white lab coat over both surgical scrubs and business casual increased clients' perceived competency and comfort levels compared to not wearing a white lab coat.

P104 One year failure rates for de novo ventriculo-peritonealshunts in under 3- month-old children

Objectives

Historically VPS failure and infection rates are higher for neonates than for older children. We compared our one year VPS failure and infection rates in under 3-month-olds with those of older children.

Design

A retrospective, single centre study comparing 1 year survival and infection rates of VPS in under 3-month-olds verses older children.

Subjects

58 children under 3 months of age underwent VPS insertion between January 2007 and December 2016.

Methods

Data was collected by three independent reviewers from electronic files and case notes. Data was analysed using descriptive statistics and one year shunt survival curves were produced.

Results

For children under 3 months there was a 29.3% one-year shunt failure rate, of which 2 were shunt infections (3.4%). In patients greater than 3 months, the shunt malfunction rate was 23.4% and the infection rate was 4.3%. There were no shunt-related mortalities in either group.

Conclusions

Children under 3-months-old undergoing VPS insertion should not automatically expect an increased 1 year failure or infection rate compared with older children. Reasons for this may be increased sub-specialisation, improved neonatal care and use of antibiotic impregnated catheters.

One year failure rates for de-novo ventriculo-peritoneal shunts in under 3-month-old children

Introduction: Ventriculo-peritoneal shunts (VPS) are still the mainstay treatment for hydrocephalus in children. It is generally accepted that VPS failure and infection rates are higher for neonates than for older children. We compared our 1-year failure and infection rates in under 3-month-old children compared with older children in our department. Results: We identified 58 children under 3 months of age who underwent VPS insertion between January 2007 and December 2016. They had a 29.3% (17) shunt failure rate over the first year. There were two confirmed shunt infections (3.4%). Discussion: The 1-year shunt failure rate at our institution for VPS insertion in children over 3 months is 26.1% and the infection rate is 4.3% (9). The literature suggests that the outcome for VPS in younger children is worse than for older children. Our work shows similar outcomes for all children compared to those under 3 months at time of VPS insertion alone. Conclusion: Children under 3-months-old undergoing VPS insertion should not automatically expect an increased 1-year failure or infection rate compared with older children. The reasons for this may be as a result of increased subspecialisation, the more widespread use of antibiotic-impregnated catheters and improved neonatal care.

Genetic risk for squamous cell carcinoma of the nictitating membrane parallels that of the limbus in Haflinger horses

Squamous cell carcinoma (SCC) is the most common cancer affecting the equine eye, with a higher incidence documented in Haflinger horses. Recently, a missense variant in the gene damage specific DNA binding protein 2 (DDB2, p.Thr338Met) on ECA12 was identified as a risk factor for the development of limbal SCC in Haflinger horses. SCC also occurs on the nictitating membrane; therefore, investigating the role of this missense variant in nictitating membrane SCC is warranted. In this study, a common ancestor was identified among Haflinger horses affected with limbal SCC or with nictitating membrane SCC, thus supporting a recessive risk factor for the development of cancer at both ocular locations. Analysis of genotype data from Haflinger horses with and without nictitating membrane SCC revealed that the same region on ECA12 associated with limbal SCC was also associated with nictitating membrane SCC (P < 2.04 × 10^-5 ). Fine mapping of this locus using 25 cases and 49 controls supported the hypothesis that DDB2:c.1013C>T, p.Thr338Met, is a risk factor for nictitating membrane SCC, as 88% of our cases were homozygous for this variant and no other polymorphism was more strongly associated (P = 4.13 × 10^-14 ). These data indicate that the genetic risk is the same for the development of both limbal and nictitating membrane SCC in Haflinger horses and validates utilization of genetic testing of the DDB2 variant for both clinical management and the guidance of mating decisions.

Field-deployable, quantitative, rapid identification of active Ebola virus infection in unprocessed blood

The West African Ebola virus outbreak underlined the importance of delivering mass diagnostic capability outside the clinical or primary care setting in effectively containing public health emergencies caused by infectious disease. Yet, to date, there is no solution for reliably deploying at the point of need the gold standard diagnostic method, real time quantitative reverse transcription polymerase chain reaction (RT-qPCR), in a laboratory infrastructure-free manner. In this proof of principle work, we demonstrate direct performance of RT-qPCR on fresh blood using far-red fluorophores to resolve fluorogenic signal inhibition and controlled, rapid freeze/thawing to achieve viral genome extraction in a single reaction chamber assay. The resulting process is entirely free of manual or automated sample pre-processing, requires no microfluidics or magnetic/mechanical sample handling and thus utilizes low cost consumables. This enables a fast, laboratory infrastructure-free, minimal risk and simple standard operating procedure suited to frontline, field use. Developing this novel approach on recombinant bacteriophage and recombinant human immunodeficiency virus (HIV; Lentivirus), we demonstrate clinical utility in symptomatic EBOV patient screening using live, infectious Filoviruses and surrogate patient samples. Moreover, we evidence assay co-linearity independent of viral particle structure that may enable viral load quantification through pre-calibration, with no loss of specificity across an 8 log-linear maximum dynamic range. The resulting quantitative rapid identification (QuRapID) molecular diagnostic platform, openly accessible for assay development, meets the requirements of resource-limited countries and provides a fast response solution for mass public health screening against emerging biosecurity threats.

Development of broad-spectrum human monoclonal antibodies for rabies post-exposure prophylaxis

Currently available rabies post-exposure prophylaxis (PEP) for use in humans includes equine or human rabies immunoglobulins (RIG). The replacement of RIG with an equally or more potent and safer product is strongly encouraged due to the high costs and limited availability of existing RIG. In this study, we identified two broadly neutralizing human monoclonal antibodies that represent a valid and affordable alternative to RIG in rabies PEP. Memory B cells from four selected vaccinated donors were immortalized and monoclonal antibodies were tested for neutralizing activity and epitope specificity. Two antibodies, identified as RVC20 and RVC58 (binding to antigenic site I and III, respectively), were selected for their potency and broad-spectrum reactivity. In vitro, RVC20 and RVC58 were able to neutralize all 35 rabies virus (RABV) and 25 non-RABV lyssaviruses. They showed higher potency and breath compared to antibodies under clinical development (namely CR57, CR4098, and RAB1) and commercially available human RIG. In vivo, the RVC20-RVC58 cocktail protected Syrian hamsters from a lethal RABV challenge and did not affect the endogenous hamster post-vaccination antibody response.

Histopathologic evidence of capecitabine corneal toxicity in dogs

In an experimental model of transplant rejection, renal transplants were performed on 6 mixed-breed dogs. Capecitabine (CPC) was administered as an oral immunosuppressive agent. All recipients received systemic CPC, cyclosporine (CSA), prednisolone, and famotidine throughout the study. Two dogs developed superficial keratitis, which was characterized by multifocal geographic erosions, superficial corneal epithelial pigmentation, and corneal neovascularization. These clinical signs correlated with the dose of CPC given, whereas other drug doses remained unchanged. After euthanasia, routine histologic sections were stained with hematoxylin and eosin and with alcian blue periodic acid-Schiff for light microscopic evaluation. Ocular histopathologic abnormalities were limited to neovascularization and inflammatory infiltrate of the anterior corneal stroma and abnormal basal cell morphology, disorganization, thinning, and pigmentation of the corneal epithelium. The purpose of this communication is to describe the clinical and histopathologic evidence of CPC corneal toxicity in dogs.

A metabolomic comparison of urinary changes in type 2 diabetes in mouse, rat, and human

Type 2 diabetes mellitus is the result of a combination of impaired insulin secretion with reduced insulin sensitivity of target tissues. There are an estimated 150 million affected individuals worldwide, of whom a large proportion remains undiagnosed because of a lack of specific symptoms early in this disorder and inadequate diagnostics. In this study, NMR-based metabolomic analysis in conjunction with multivariate statistics was applied to examine the urinary metabolic changes in two rodent models of type 2 diabetes mellitus as well as unmedicated human sufferers. The db/db mouse and obese Zucker (fa/fa) rat have autosomal recessive defects in the leptin receptor gene, causing type 2 diabetes. 1H-NMR spectra of urine were used in conjunction with uni- and multivariate statistics to identify disease-related metabolic changes in these two animal models and human sufferers. This study demonstrates metabolic similarities between the three species examined, including metabolic responses associated with general systemic stress, changes in the TCA cycle, and perturbations in nucleotide metabolism and in methylamine metabolism. All three species demonstrated profound changes in nucleotide metabolism, including that of N-methylnicotinamide and N-methyl-2-pyridone-5-carboxamide, which may provide unique biomarkers for following type 2 diabetes mellitus progression.

An update on the Kevorkian-Reding 93 physician-assisted deaths in Michigan: is Kevorkian a savior, serial-killer or suicidal martyr?

This report presents an update of the Kevorkian-Reding physician-assisted (or physician-aided) deaths to include the ninety-three publicly acknowledged cases as of November 25, 1998. These deaths are divided into ten distinct time phases. The following trends emerge. Over two-thirds of the decedents are women, the ratio of females to males varying widely with phase. The proportion of women seems to be the highest when Kevorkian is free to act as he wants and lowest when he seems to be acting under legal or political restraints. Based on autopsy results, only 29.0 percent of the cases are terminal, this percentage being higher among men (37.9%) than among women (25.4%). However, 66.7% of the decedents were disabled, no significant difference emerging between men and women. Further, five out of the six decedents showing no apparent anatomical sign of disease at autopsy were women. Over 80 percent of the physician-assisted deaths are cremated, approximately twice as high a proportion as that emerging for suicides in Michigan and four times as high as cremations occurring with regard to overall deaths. Finally, death by carbon monoxide decreases dramatically with time phase while the use of the contraption dubbed the "suicide machine" increases, suggesting an increasing routinization over time. Finally, during the ninth and tenth phases, Kevorkian's aims and his own suicidality emerge more clearly involving 1) harvesting organs and 2) threat of starving himself in prison if he is convicted. Phase 10 can be seen as an escalation from assisted death to overt euthanasia, repeating the same need for a demonstration (Thomas Youk) that was first exhibited in Phase I (Janet Adkins).

How could pathologists improve the initial diagnosis of colitis? Evidence from an international workshop

BACKGROUND

The taking of multiple colorectal biopsies is in widespread use although there is little research into their benefit for the pathological diagnosis of inflammatory bowel disease. There is also still debate about appropriate morphological criteria for interpreting these biopsies.

AIMS

To determine the effect of single versus multiple biopsies on the accuracy of diagnosis and to study the accuracy and reproducibility of the different criteria used in the diagnosis of multiple biopsies by expert and non-expert pathologists.

METHOD

Thirteen expert and 12 non-expert international diagnostic histopathologists attended a workshop. Sixty cases with full follow up were viewed, blinded, in two rounds. Diagnoses were made on rectal biopsies and then full colonoscopic series.

RESULTS

Experts correctly identified 24% of Crohn's disease cases (non-experts, 12%) from the rectal biopsies. This improved to 64% (non-experts, 60%) with the full series. The accuracy of the diagnosis of ulcerative colitis also improved slightly with the full series from 64% to 74% overall. Experts had a similar (moderate) level of agreement and accuracy to non-experts. For Crohn's disease, the likelihood ratios (LR) for the most important individual features were 12.4 for granulomas and 3.3 for focal or patchy inflammation. Features favouring ulcerative colitis were diffuse crypt architectural irregularity (LR, 3.4), general crypt epithelial polymorphs (LR, 3.7), and reduced crypt numbers (LR, 2.9).

CONCLUSIONS

A full colonoscopic series gave more accurate diagnosis than a rectal biopsy. Accurate pathologists used the same evidence based criteria for multiple biopsies as for single biopsies.

The role of radiography in primary care patients with low back pain of at least 6 weeks duration: a randomised (unblinded) controlled trial

OBJECTIVES

To test the hypotheses that: (1) Lumbar spine radiography in primary care patients with low back pain is not associated with improved patient outcomes, including pain, disability, health status, sickness absence, reassurance, and patient satisfaction or belief in the value of radiography. (2) Lumbar spine radiography in primary care patients with low back pain is not associated with changes in patient management, including medication use, and the use of primary and secondary care services, physical therapies and complementary therapies. (3) Participants choosing their treatment group (i.e. radiography or no radiography) do not have better outcomes than those randomised to a treatment group. (4) Lumbar spine radiography is not cost-effective compared with usual care without lumbar spine radiography.

DESIGN

A randomised unblinded controlled trial.

SETTING

Seventy-three general practices in Nottingham, North Nottinghamshire, Southern Derbyshire, North Lincolnshire and North Leicestershire. Fifty-two practices recruited participants to the trial.

SUBJECTS

Randomised arm: 421 participants with low back pain, with median duration of 10 weeks. Patient preference arm: 55 participants with low back pain, with median duration of 11 weeks.

INTERVENTION

Lumbar spine radiography and usual care versus usual care without radiography.

MAIN OUTCOME MEASURES

Roland adaptation of the Sickness Impact Profile, visual analogue pain scale, health status scale, EuroQol, use of primary and secondary care services, and physical and complementary therapies, sickness absence, medication use, patient satisfaction, reassurance and belief in value of radiography at 3 and 9 months post-randomisation.

RESULTS

Participants randomised to receive an X-ray were more likely to report low back pain at 3 months (odds ratio (OR) = 1.56; 95% confidence interval (CI), 1.02 to 2.40) and had a lower overall health status score (p = 0.02). There were no differences in health or functional status at 9 months. A higher proportion of participants consulted the general practitioner (GP) in the 3 months following an X-ray (OR = 2.72; 95% CI, 1.80 to 4.10). There were no differences in use of any other services, medication use or sickness absence at 3 or 9 months. No serious spinal pathology was identified in either group. The commonest X-ray reports were of discovertebral degeneration and normal findings. Many patients did not perceive their information needs were met within the consultation. Satisfaction with care was greater in the group receiving radiography at 9 months. Participants randomised to receive an X-ray were not less worried, or more reassured about serious disease causing their low back pain. Satisfaction was associated with meeting participants' information needs and reduced belief in the necessity for investigations for low back pain, including X-rays and blood tests. In both groups, at 3 and 9 months 80% of participants would choose to have an X-ray if the choice was available. Participants in the patient preference group achieved marginally better outcomes than those randomised to a treatment group, but the clinical significance of these differences is unclear. Lumbar spine radiography was associated with a net economic loss at 3 and 9 months.

CONCLUSIONS

Lumbar spine radiography in primary care patients with low back pain of at least 6 weeks duration is not associated with improved functioning, severity of pain or overall health status, and is associated with an increase in GP workload. Participants receiving X-rays are more satisfied with their care, but are not less worried or more reassured about serious disease causing their low back pain. CONCLUSIONS - RECOMMENDATIONS FOR FURTHER RESEARCH: Further work is required to develop and test an educational package that educates patients and GPs about the utility of radiography and provides strategies for identifying and meeting the information needs of patients, and the needs of patients and GPs to be reassured about missing serious disease. Guidelines on the management of low back pain in primary care should be consistent about not recommending lumbar spine radiography in patients with low back pain in the absence of red flags for serious spinal pathology, even if the pain has persisted for at least 6 weeks.

A case of Peters' anomaly in a springer spaniel

An 8-week-old springer spaniel presented with a large central corneal opacity of the left globe, which was accompanied by cords of tissue spanning from the iris collarette to the posterior cornea. A posterior cortical cataract was noted in the right eye. At the owner's request the puppy was humanely destroyed, and a necropsy was performed. Upon sectioning the left globe in the vertical plane, a circle of pigmented strands of tissue was observed spanning the anterior chamber from the iris to the posterior aspect of the cornea. The right globe appeared normal when inspected grossly. Histologically, a membrane of pigmented tissue covered the posterior aspect of the broad central corneal leukoma of the left globe. This membrane and the cords traversing the anterior chamber were composed of vascular uveal tissue. Descemet's membrane and the corneal endothelium were reduced or absent in the zone of corneal opacity. Other than the changes associated with cataract, the right globe was histologically normal. The clinical and histological findings in the left globe were identical with those described for Peters>> anomaly in human beings.

Morphology and immunohistochemistry of spontaneous chronic corneal epithelial defects (SCCED) in dogs

PURPOSE

To determine the morphologic features of the epithelium and extracellular matrix in spontaneous chronic corneal epithelial defects (SCCED) in dogs.

METHODS

Forty-eight superficial keratectomy specimens were obtained after confirmation of the presence of a superficial corneal erosion for longer than 3 weeks with no discernible underlying cause. Histologic samples were examined by light microscopy, scanning electron microscopy, and transmission electron microscopy. Immunolocalization of laminin, collagen IV, fibronectin, and collagen VII was performed.

RESULTS

Epithelial cells adjacent to the defect were poorly attached to the underlying extracellular matrix. A prominent superficial stromal hyaline acellular zone composed of collagen fibrils in the area of the erosion was present in most specimens. Samples exhibited a varying degree of fibroplasia, vascularization, and leukocytic infiltrate. Laminin, collagen IV, and collagen VII were usually either not present or were present only in discontinuous segments on the surface of the erosion. Fibronectin usually coated the surface of the erosion, either as a continuous sheet or in discontinuous segments. Transmission electron microscopy of 15 samples revealed that the basement membrane was either absent in the area of the erosion or was present only in discontinuous segments. Scanning electron microscopy of eight of nine samples confirmed the absence of continuous basement membrane. Epithelial and extracellular matrix components in the peripheral cornea appeared normal.

CONCLUSIONS

Most canine patients with spontaneous chronic corneal epithelial defects do not have a normal basement membrane structure in the region of the epithelial defect and have other abnormalities in the subjacent extracellular matrix that may reflect a part of the underlying pathophysiology of chronic and recurrent erosions.

Spontaneous chronic corneal epithelial defects (SCCED) in dogs: clinical features, innervation, and effect of topical SP, with or without IGF-1

PURPOSE

To delineate the clinical features and alterations in innervation and substance P (SP) content in spontaneous chronic corneal epithelial defects (SCCED) in dogs and to conduct a preliminary investigation evaluating the efficacy of topical SP, with or without insulin-like growth factor (IGF)-1, in the treatment of this disorder.

METHODS

Complete ophthalmic examinations, including Cochet-Bonnet aesthesiometry, were performed in 45 canine patients that had spontaneous corneal epithelial defects of at least 3 weeks' duration and with no identifiable cause. Eighteen patients had superficial keratectomies performed, and the corneal nerves were labeled immunohistochemically with antibodies against protein gene product (PGP)-9.5, SP, vasoactive intestinal peptide (VIP), and tyrosine hydroxylase (TH). Relative fiber densities were assessed qualitatively and quantitatively. Corneal epithelial cell and tear SP contents were determined in affected and normal dogs by an enzyme immunoassay. A preliminary open-label treatment trial of topical SP, with and without IGF-1, was conducted in 21 dogs.

RESULTS

The duration of the erosion before admittance into the study was a mean of 9.22 weeks (range, 3-52). The average patient was middle aged (mean, 9.25 +/- 1.85 years [SD]); no sex predisposition of the disease was identified. Boxers, golden retrievers, and keeshonds were overrepresented when compared with the normal hospital population. Corneal sensation was normal. Marked alterations in corneal innervation were identified in affected dogs with abnormal increased SP and calcitonin gene-related peptide (CGRP)-immunoreactive nerve plexuses identified surrounding the periphery of the epithelial defect. The SP content of epithelial cells surrounding the defect increased, whereas the tear SP content remained unchanged. Of the canine patients treated with SP, with or without IGF-1, 70% to 75% had complete healing of the defect.

CONCLUSIONS

This idiopathic spontaneous corneal disease in dogs shares clinical features with chronic epithelial defects in humans. The presence of marked alterations in peptidergic innervation and positive response to topical therapy with SP suggest that SP plays a critical role in corneal wound-healing processes.

Radiography of the lumbar spine in primary care patients with low back pain: randomised controlled trial

OBJECTIVE

To test the hypothesis that radiography of the lumbar spine in patients with low back pain is not associated with improved clinical outcomes or satisfaction with care.

DESIGN

Randomised unblinded controlled trial.

SETTING

73 general practices in Nottingham, north Nottinghamshire, southern Derbyshire, north Lincolnshire, and north Leicestershire. 52 practices recruited participants to the trial.

SUBJECTS

421 patients with low back pain of a median duration of 10 weeks.

INTERVENTION

Radiography of the lumbar spine.

MAIN OUTCOME MEASURES

Roland adaptation of the sickness impact profile, visual analogue scale for pain, health status, EuroQol, satisfaction with care, use of primary and secondary care services, and reporting of low back pain at three and nine months after randomisation.

RESULTS

The intervention group were more likely to report low back pain at three months (relative risk 1.26, 95% confidence interval 1.00 to 1.60) and had a lower overall health status score and borderline higher Roland and pain scores. A higher proportion of participants consulted their doctor in the three months after radiography (1.62, 1.33 to 1.97). Satisfaction with care was greater in the group receiving radiography at nine but not three months after randomisation. Overall, 80% of participants in both groups at three and nine months would have radiography if the choice was available. An abnormal finding on radiography made no difference to the outcome, as measured by the Roland score.

CONCLUSIONS

Radiography of the lumbar spine in primary care patients with low back pain of at least six weeks' duration is not associated with improved patient functioning, severity of pain, or overall health status but is associated with an increase in doctor workload. Guidelines on the management of low back pain in primary care should be consistent about not recommending radiography of the lumbar spine in patients with low back pain in the absence of indicators for serious spinal disease, even if it has persisted for at least six weeks. Patients receiving radiography are more satisfied with the care they received. The challenge for primary care is to increase satisfaction without recourse to radiography.

Research capacity in UK primary care

BACKGROUND

Moves towards a 'primary care-led' National Health Service (NHS) and towards evidence-based care have focused attention upon the need for evaluative research relating to the structure, delivery, and outcome of primary health care in the United Kingdom (UK). This paper describes work carried out to inform the Department of Health Committee on Research and Development (R&D) in Primary Care (Mant Committee).

AIM

To describe the extent and nature of current research capacity in primary care in the UK and to identify future needs and priorities.

METHOD

Funding data were requested from NHS National Programmes, NHS Executive Regional Offices, the Department of Health (DoH), Scottish Office, Medical Research Council, and some charities. A postal survey was sent to relevant academic departments, and appropriate academic journals were reviewed from 1992 to 1996. In addition, interviews were conducted with academic and professional leaders in primary care.

RESULTS

Overall, total annual primary care R&D spend by the NHS and the DoH was found to be 7% of the total spend, although annual primary care R&D spend differs according to funding source. Journals relating to primary care do not, with some notable exceptions (e.g. British Journal of General Practice, Family Practice), have high academic status, and research into primary care by academic departments is, with perhaps the exception of general practice, on a small scale. The research base of most primary care professions is minimal, and significant barriers were identified that will need addressing if research capacity is to be expanded.

CONCLUSION

There are strong arguments for the development of primary care research in a 'primary care-led' NHS in the UK. However, dashes for growth or attempts to expand capacity from the present infrastructure must be avoided in favour of endeavours to foster a sustainable, long-term research infrastructure capable of responding meaningfully to identified needs.

Combined cycloablation and gonioimplantation for treatment of glaucoma in dogs: 18 cases (1992-1998)

OBJECTIVE

To evaluate a combined cycloablative and gonioimplantation technique for treatment of glaucoma in dogs.

DESIGN

Retrospective study.

ANIMALS

18 adult dogs with glaucoma.

PROCEDURE

Medical records of dogs that received a valved gonioimplant and a cyclodestructive procedure (cyclocryoablation or diode laser cyclophotocoagulation) during a 6-year period were reviewed. Retention of vision and intraocular pressure control were assessed, as well as number and nature of complications.

RESULTS

19 eyes of 18 dogs received a valved gonioimplant and either cyclocryoablation (n = 12) or diode laser cyclophotocoagulation (7). At > or = 1 year after surgery, 11 of 19 eyes had vision and 14 of 19 eyes had intraocular pressure < 25 mm Hg. Two dogs (2 eyes) were lost to follow-up 3 and 6 months after surgery. Despite the alternative route for aqueous humor flow created by the gonioimplant, 7 eyes had increased intraocular pressure (27 to 61 mm Hg) < 24 hours after surgery. Other complications included excessive intraocular fibrin, focal retinal detachment, corneal ulcer, retinal hemorrhage, cataract, and implant migration.

CONCLUSIONS AND CLINICAL RELEVANCE

Combined cycloablation and gonioimplantation appears to be a promising technique for retention of vision and control of intraocular pressure in dogs with glaucoma.

Fine mapping of 39 ESTs on human chromosome 6p23-p25

Loci conferring susceptibility to schizophrenia, coeliac disease, and orofacial clefting have been assigned to the 6p23-p25 region of human chromosome 6. To facilitate the identification of candidate genes we have sublocalized and ordered 39 ESTs assigned to this interval by radiation hybrid mapping. This was achieved by generating PAC contigs containing the ESTs, genetic markers, and random STSs. For full integration into previously published data a single YAC contig spanning 6p23-p25 was used to unambiguously order the PAC contigs and ESTs along the chromosome. The majority of the ESTs (31/39) were positioned in the 6p23-p24 interval at the proximal half of the map, and of these 8 are located within a single PAC clone. The order of known genes in this region is cen-CD83-ZNF40-EDN1-(GCNT2, CAPZB)-TFAP2-BMP6-DSP-tel.

The rationale, organisation and evaluation of a campaign to increase the use of sugar-free paediatric medicines

OBJECTIVE

To conduct and evaluate a dental health education campaign to encourage the use of sugar-free rather than sugar-containing medicines.

DESIGN

Meetings were organised for general medical practitioners, pharmacists and health visitors where the campaign was explained and discussed. Leaflets were given to parents by the health professionals. The campaign targeted the use of children's medicines from several aspects, namely when recommended, prescribed, sold and used.

SETTING

The campaign was conducted in the North West Region.

SUBJECTS

The campaign was directed at parents of young children, and health professionals, namely, general medical practitioners, pharmacists and health visitors.

OUTCOME MEASURES

Evaluation was by means of questionnaires, sales figures and prescriptions of medicines.

RESULTS

There was an increase in the proportion of sugar-free paracetamol prescribed in five out of six districts. The frequency of sugar intakes as an important cause of dental caries was not understood by many health professionals.

CONCLUSIONS

Continued education for health professionals is needed in order to show the importance of the frequency of sugar intakes and to dispel some prevalent dental health misconceptions.

Impact of level III verification on trauma admissions and transfer: comparisons of two rural hospitals

PURPOSE

To study the impact of Level III verification and other changes in rural hospitals on trauma delivery and to examine factors affecting transfer to a Level I trauma center.

SETTING

Two rural Kentucky hospitals and a Level I trauma center.

METHOD OF REVIEW

Concurrent review of all trauma patients in 1988 and re-review of the same parameters in 1995.

FINDINGS

In 1988, both hospitals had similar management practices in trauma care. A significant number of patients were transferred for (a) patient choice, (b) serious and/or multiple trauma, (c) specialty care in non-life threatening situations, and (d) to exclude a potentially serious problem seen on radiologic evaluation (usually questionable cervical spine or widened mediastinum). Both hospitals had major changes in trauma delivery. One hospital received Level III verification, and the other had changes that lessened the general surgeon's involvement with initial evaluation and treatment. A re-review in 1995 disclosed major changes at both institutions. Transfers to exclude radiologic abnormalities had virtually disappeared. The Level III status had increased the surgical involvement in that hospital; there was actually an increase in patients transferred to the Level I hospital and an increase in patient acuity. More operations were performed locally, and the care was more efficiently delivered. The other hospital had a large increase in transfers and decreased admissions locally as general surgical involvement decreased.

CONCLUSIONS

The factors related to patient transfer for trauma care are complex and require careful elucidation to improve care. The development of a Level III trauma service appeared to increase the number of seriously injured patients treated in the rural hospital and the efficiency of the care delivered.

The identification of novel gene sequences of the human adult testis

To facilitate the characterization of genetic expression in human adult testis, expressed sequence tag analysis of cDNAs from this tissue has been undertaken. Over 180 kb of DNA sequence has been determined and used to search the GenBank database. The results from the first 359 cDNA clones analyzed indicate that the sequences could be sorted into several categories with a high proportion being novel. Twenty-five clones (7%) showed 100% identity with human genes, 11 (3%) with prokaryotic sequences, 21 (5%) with between 60 and 95% similarity to human genes, 27 (8%) with between 60 and 95% similarity to genes from other species, and 33 (9%) with matches to human repeat sequences. Two hundred forty-two (67%) showed no significant matches and thus are likely to represent novel transcripts. In comparison to similar studies on human brain tissue and a hepatoma cell line, the findings indicate that the matches in the testis transcript population appear to be identifying a different spectrum of gene sequences.

Sugar-containing or sugar-free paediatric medicines: does it really matter?

The long-term use of sugar-containing medicines has long been considered a cause of dental caries in children. Several studies have examined the role of prescription medicines in dental decay, but what about those that can be bought over the counter and that are used infrequently? In this paper practitioners are advised on how to encourage parents to use sugar-free medicines for the sake of their children's teeth.

Dental health. I. Views about preventive dental care for infants

A study to investigate attitudes of health visitors and parents to preventive dental health care for young children revealed that while the majority of parents agreed early dental visits were important, few had taken their child to the dentist before the age of one year. Where dental health is poor it is vital that the health visitor continues to give parents appropriate dietary advice and to recommend early visits to the dentist, writes Elaine Bentley.

Molecular genetic investigation of sporadic renal cell carcinoma: analysis of allele loss on chromosomes 3p, 5q, 11p, 17 and 22

To investigate the role of tumour-suppressor genes on the short arm of chromosome 3 in the mechanism of tumorigenesis in non-familial renal cell carcinoma, we analysed 55 paired blood-tumour DNA samples for allele loss on chromosome 3p and in the region of known or putative tumour-suppressor genes on chromosomes 5, 11, 17 and 22. Sixty-four per cent (35/55) of informative tumours showed loss of heterozygosity (LOH) of at least one locus on the short arm of chromosome 3, compared with only 13% at the p53 tumour-suppressor gene and 6% at 17q21. LOH at chromosome 5q21 and 22q was uncommon (2-3%). Detailed analysis of the regions of LOH on chromosome 3p suggested that, in addition to the VHL gene in chromosome 3p25-p26, mutations in one or more tumour-suppressor genes in chromosome 3p13-p24 may be involved in the pathogenesis of sporadic renal cell carcinoma (RCC). We also confirmed previous suggestions that chromosome 3p allele loss is not a feature of papillary RCC (P < 0.05).

Molecular genetic investigations of the mechanism of tumourigenesis in von Hippel-Lindau disease: analysis of allele loss in VHL tumours

Von Hippel-Lindau (VHL) disease is a dominantly inherited familial cancer syndrome characterised by the development of retinal and central nervous system haemangioblastomas, renal cell carcinoma (RCC), phaeochromocytoma and pancreatic tumours. The VHL disease gene maps to chromosome 3p25-p26. To investigate the mechanism of tumourigenesis in VHL disease, we analysed 24 paired blood/tumour DNA samples from 20 VHL patients for allele loss on chromosome 3p and in the region of tumour suppressor genes on chromosomes 5, 11, 13, 17 and 22. Nine out of 24 tumours showed loss of heterozygosity (LOH) at at least one locus on chromosome 3p and in each case the LOH included the region to which the VHL gene has been mapped. Chromosome 3p allele loss was found in four tumour types (RCC, haemangioblastoma, phaeochromocytoma and pancreatic tumour) suggesting a common mechanism of tumourigenesis in all types of tumour in VHL disease. The smallest region of overlap was between D3S1038 and D3S18, a region that corresponds to the target region for the VHL gene from genetic linkage studies. The parental origin of the chromosome 3p25-p26 allele loss could be determined in seven tumours from seven familial cases; in each tumour, the allele lost had been inherited from the unaffected parent. Our results suggest that the VHL disease gene functions as a recessive tumour suppressor gene and that inactivation of both alleles of the VHL gene is the critical event in the pathogenesis of VHL neoplasms. Four VHL tumours showed LOH on other chromosomes (5q21, 13q, 17q) indicating that homozygous VHL gene mutations may be required but may not be sufficient for tumourigenesis in VHL disease.

Presymptomatic diagnosis of von Hippel-Lindau disease with flanking DNA markers

Von Hippel-Lindau (VHL) disease is a dominantly inherited cancer syndrome characterised by the development of retinal, cerebellar, and spinal haemangioblastomas, renal cell carcinoma, and phaeochromocytoma. The gene for VHL disease has been mapped to chromosome 3p25-p26 and flanking markers identified. We have investigated the usefulness of currently available DNA markers for the presymptomatic diagnosis of VHL disease. In the first part of this investigation, genetic linkage data from two previously published studies were updated and reanalysed to provide accurate estimates of sex specific recombination fractions and to confirm that there is no evidence of locus heterogeneity. In the second part of this study, 14 families containing 23 asymptomatic subjects at 50% prior risk of VHL disease were investigated with closely linked DNA markers (RAF1, D3S18, D3S732). Seventeen subjects were informative with one or more markers, six of whom were informative at markers flanking the VHL disease gene. By combining age related and DNA based risk information the carrier risk for 11 subjects was reduced to < 2%.

Cloning of the X-linked glycerol kinase deficiency gene and its identification by sequence comparison to the Bacillus subtilis homologue

cDNA clones from a human adult testis cDNA library were isolated and sequenced as part of a programme to produce expressed sequence tags (ESTs). ESTs were used routinely to search DNA and protein sequence databases. One clone (142) showed 60% identity to the Bacillus subtilis glycerol kinase gene at both the DNA and amino acid sequence levels. Analysis of DNA from somatic cell hybrids carrying deleted X chromosomes, has shown that clone 142 detects homologous sequences between Xp21.2-p22.1 (the interval containing the locus responsible for glycerol kinase deficiency--GKD). These sequences are deleted in two patients with GKD. Clone 142 also detects homologous sequences on Xq and at several autosomal loci. The sequences of clone 142 and two further cDNA clones isolated from a human foetal brain cDNA library are presented.

Mapping of the von Hippel-Lindau disease locus to a small region of chromosome 3p by genetic linkage analysis

Genetic linkage studies were performed in 22 families with von Hippel-Lindau (VHL) disease by using polymorphic DNA markers from distal chromosome 3p. Linkage was detected between VHL disease and the markers D3S18 (Zmax = 6.6 at theta = 0.0, confidence interval (CI) 0.00-0.06), RAF1 (Zmax = 5.9 at theta = 0.06, CI 0.01-0.16), and THRB (Zmax 3.4 at theta = 0.11). Multipoint linkage analysis localized the VHL disease gene within a small region (approximately 8 cM) of 3p25-p26 between RAF1 and (D3S191, D3S225) and close to the D3S18 locus. There was no evidence of locus heterogeneity, and families with and without pheochromocytoma showed linkage to D3S18. The identification of DNA markers flanking the VHL disease gene allows reliable presymptomatic and prenatal diagnosis to be offered to informative families.

Mapping of von Hippel-Lindau disease to chromosome 3p confirmed by genetic linkage analysis

Genetic linkage studies were performed in 12 British families with von Hippel-Lindau disease (VHL) using RFLPs at three loci (DNF15S2, THRB, RAF1) on the short arm of chromosome 3. Linkage was detected between the VHL disease locus and RAF1 with a maximum lod score of 3.88 at a recombination fraction of 0.05 (confidence interval 0.003-0.18). Multipoint linkage analysis suggested that the most likely location for the VHL disease locus is telomeric to THRB. These results confirm earlier reports localizing the VHL gene to the short arm of chromosome 3, and provide no evidence for genetic heterogeneity.

Generalized juvenile polyposis with carcinoma

Generalized juvenile polyposis usually is not associated with an increased risk for gastrointestinal carcinoma. A subgroup of patients, however, have juvenile polyps with adenomatous features. A case report of juvenile polyposis, together with adenocarcinoma of the colon and review of the literature, are presented to emphasize the potential for malignancy in this subgroup of patients and to guide appropriate evaluation.

Effect of oral iron therapy on the upper gastrointestinal tract. A prospective evaluation

This study assesses the effect of oral iron therapy on the upper gastrointestinal tract and fecal occult blood testing. Fourteen healthy volunteers completed a checklist of gastrointestinal symptoms, underwent endoscopy and biopsy of the stomach and duodenum, and supplied a fresh stool sample for Hemoccult and HemoQuant testing. They then took ferrous sulfate 325 mg per os tid for two weeks and had the same evaluation repeated. Gastrointestinal symptoms were rated by the patients on a scale of 0-3, endoscopic findings were numerically scored (0-4), and the biopsies were graded blindly. Thirteen other healthy volunteers took ferrous sulfate 325 mg per os tid for one week and had Hemoccult testing of stool at days 0 and 7. All subjects developed dark stools, and significant nausea and diarrhea were noted (0.1 +/- 0.1 to 0.9 +/- 0.3, P less than 0.05 for both symptoms). Only 1/27 had a questionably trace-positive Hemoccult test (two observers disagreed) and no significant difference was seen in HemoQuant testing (1.4 +/- 0.5 to 1.8 +/- 0.7 mg Hb/g). A significant increase was seen in endoscopic abnormalities in the stomach (0.1 +/- 0.1 to 1.5 +/- 0.3, P = 0.003), consisting of erythema, small areas of subepithelial hemorrhage, and, in two subjects, erosions. Biopsies showed no significant change after iron therapy. We conclude that (1) oral ferrous sulfate rarely causes Hemoccult-positive stools, and patients with positive Hemoccult tests on iron therapy require further evaluation; and (2) oral iron may cause mild endoscopic abnormalities in the stomach which are of uncertain clinical significance.