Tenofovir Douche as HIV Preexposure Prophylaxis for Receptive Anal Intercourse: Safety, Acceptability, Pharmacokinetics, and Pharmacodynamics (DREAM 01)

BACKGROUND

Despite highly effective HIV preexposure prophylaxis (PrEP) options, no options provide on-demand, nonsystemic, behaviorally congruent PrEP that many desire. A tenofovir-medicated rectal douche before receptive anal intercourse may provide this option.

METHODS

Three tenofovir rectal douches-220 mg iso-osmolar product A, 660 mg iso-osmolar product B, and 660 mg hypo-osmolar product C-were studied in 21 HIV-negative men who have sex with men. We sampled blood and colorectal tissue to assess safety, acceptability, pharmacokinetics, and pharmacodynamics.

RESULTS

The douches had high acceptability without toxicity. Median plasma tenofovir peak concentrations for all products were several-fold below trough concentrations associated with oral tenofovir disoproxil fumarate (TDF). Median colon tissue mucosal mononuclear cell (MMC) tenofovir-diphosphate concentrations exceeded target concentrations from 1 hour through 3 to 7 days after dosing. For 6-7 days after a single product C dose, MMC tenofovir-diphosphate exceeded concentrations expected with steady-state oral TDF 300 mg on-demand 2-1-1 dosing. Compared to predrug baseline, HIV replication after ex vivo colon tissue HIV challenge demonstrated a concentration-response relationship with 1.9 log10 maximal effect.

CONCLUSIONS

All 3 tenofovir douches achieved tissue tenofovir-diphosphate concentrations and colorectal antiviral effect exceeding oral TDF and with lower systemic tenofovir. Tenofovir douches may provide a single-dose, on-demand, behaviorally congruent PrEP option, and warrant continued development. Clinical Trials Registration . NCT02750540.

Digitally Recording Comfort Observations in the Last Days of Life

Background: 37.5% of deaths in our area occur in hospital. There are known high unmet needs of adult patients dying in hospital, this unmet need can be reduced by using an individualised care plan and specialist palliative care review. Intervention: In 2022 UHSussex developed an electronic comfort observation chart and individualised care plan, with a centralised dashboard allowing Palliative Care Teams (SPCT) to view trends, target interventions, and a rolling prospective audit. Results: 3000 patients have had their care supported with electronic comfort observations (e-comfort obs). Over 72% of all deaths in the Trust in the last 3 months have been on e-comfort obs, with 2/3 of all deaths in the first 12 months on e-comfort obs. The average length of time on e-comfort obs is 4 days resulting in 70,000 sets of e-comfort obs recorded since launch. Seven percent of e-comfort obs record moderate or severe symptoms. We have identified benefits to people who are dying, those important to them, ward staff, SPCT and on a systems level. Conclusion: E-comfort obs can be successfully embedded in a large acute Trust. This development should improve quality of end of life care in our hospitals both for individuals and for future patients, through on-going targeted education and intervention. Further work is needed to develop the system further including integrating data from electronic prescribing.

Development of a radiographic technique for porcine head ballistic research

INTRODUCTION

The porcine model shows structural features comparable to that of humans and are routinely used within research, due to the ethical, legal, and practical use of post-mortem human samples. Methods for obtaining high quality and comparable reference data using standardised acquisition protocols are essential.

METHODS

The decapitated heads of three adult white sows were subjected to radiographic imaging before and after cranial trauma (9 mm, Heckler and Koch MP5). Digital radiographs were generated using a Siemens MULTIX TOP system with an Agfa digital detector, with foam blocks and sandbags as ancillary equipment. An iterative approach was adopted by the authors to generate reproducible radiographic views from two perpendicular angles. Specimens were kept at 5 °C and wrapped in polythene bags to reduce the impact of putrefaction.

RESULTS

Standardised head radiography technique was developed for superior-inferior and lateral views demonstrating porcine anatomy. Key parameters included: automatic exposure control for tube current (∼4 mAs), tube voltage of 73 kVp, 100 cm source to image receptor distance, and an anti-scatter grid. Slight variances in specimen morphology, developmental status, and soft tissue changes did not affect imaging outcomes.

CONCLUSION

The technique and positioning proposed in this study allows for the acquisition of high quality and reproducible radiographic images for comparable ballistic research datasets. Specimen positioning and centring of the primary beam may be applied across porcine breeds, although individual radiographic parameters may differ according to equipment specifications and specimen size.

IMPLICATIONS FOR PRACTICE

Development of a reproducible radiographic technique of porcine heads in forensic and veterinary research.

Can retrospectively fusing SPECT to CT images reduce radiation doses in myocardial perfusion imaging?

INTRODUCTION

To establish if the CT dataset acquired during the stress element of myocardial perfusion imaging can be fused to the subsequent rest scan to reduce radiation doses from these procedures.

METHODS

86 rest scans were processed and evaluated using a self-designed project specific tool. Recording processing time, the time between the two data sets selected for fusion and assessing radiographic reports to ensure produced images were of diagnostic quality.

RESULTS

70% of fused scans were acquired 6-7 days apart; the mean (SD) processing time was calculated as 2.03 (0.36) minutes. The Pearson's correlation between these two variables was determined to be 0.22, showing a slight positive correlation although not statistically significant. 100% of the images produced were of diagnostic quality.

CONCLUSION

Rest scans can be fused to a previously acquired CT, careful consideration should be given when positioning the patient and to the time interval between acquiring the two data sets, departmental guidelines can assist with this. Staff training may also be beneficial to ensure staff can assess if data sets are fusible prior to completing a scan.

IMPLICATIONS FOR PRACTICE

This data provides evidence that retrospective fusion can reduce patient radiation doses in myocardial perfusion imaging without compromising diagnostic outcomes. Dose optimisation is an essential part of the ionising radiation (medical exposure) regulations therefore retrospective fusion should be considered in practice to ensure departmental compliance, although it is noteworthy this study is solely based in a single centred one camera department.

Short Communication: Identification of equine corticotropin-like intermediate lobe peptide (CLIP) binding to an adrenocortipcotrophic hormone (ACTH) assay capture antibody

A chemiluminescent immunoassay is commonly employed to measure adrenocorticotrophic hormone (ACTH) concentrations to assist pituitary pars intermedia dysfunction diagnosis. In a previous study, seasonally-dependent assay cross-reactivity to endogenous equine corticotropin-like intermediate lobe peptide (CLIP, ACTH 18-39) was suspected. The present study aimed to demonstrate binding of endogenous equine CLIP to the capture antibody of the ACTH chemiluminescent immunoassay. Liquid chromatography - mass spectrometry (LCMS) methods were optimised to identify selected ions from synthetic human ACTH, α-melanocyte stimulating hormone (α-MSH, ACTH 1-17) and CLIP. Synthetic ACTH and CLIP bound to the capture antibody of the chemiluminescent ACTH assay, but α-MSH did not. Equine endogenous CLIP was detected by LCMS in pony plasma taken in the autumn and could be eluted from the capture antibody of the ACTH chemiluminescent immunoassay. Further research is required to enable quantification of CLIP. Equine CLIP may alter measured ACTH concentrations in vivo.

Gut dysbiosis and inflammatory blood markers precede HIV with limited changes after early seroconversion

BACKGROUND

Alterations in the gut microbiome have been associated with HIV infection, but the relative impact of HIV versus other factors on the gut microbiome has been difficult to determine in cross-sectional studies.

METHODS

To address this, we examined the gut microbiome, serum metabolome, and cytokines longitudinally within 27 individuals before and during acute HIV using samples collected from several ongoing cohort studies. Matched control participants (n=28) from the same cohort studies without HIV but at similar behavioral risk were used for comparison.

FINDINGS

We identified few changes in the microbiome during acute HIV infection, but did find alterations in serum metabolites involving secondary bile acid (lithocholate sulfate, glycocholenate sulfate) and amino acid metabolism (3-methyl-2-oxovalerate, serine, cysteine, N-acetylputrescine). Greater microbiome differences, including decreased Bacteroides spp and increased Megasphaera elsdenii, were seen when comparing pre-HIV infection visits to matched at-risk controls. Those who acquired HIV also had elevated inflammatory cytokines (TNF-α, B cell activating factor, IL-8) and bioactive lipids (palmitoyl-sphingosine-phosphoethanolamide and glycerophosphoinositol) prior to HIV acquisition compared to matched controls.

INTERPRETATION

Longitudinal sampling identified pre-existing microbiome differences in participants with acute HIV compared to matched control participants observed over the same period. These data highlight the importance of increasing understanding of the role of the microbiome in HIV susceptibility.

FUNDING

This work was supported by NIH/NIAID (K08AI124979; P30AI117943), NIH/NIDA (U01DA036267; U01DA036939; U01DA036926; U24DA044554), and NIH/NIMH (P30MH058107; R34MH105272).

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Delivering evidence-based interventions for type 1 diabetes in the virtual world - A review of UK practice during the SARS-CoV-2 pandemic

AIMS

This review considers the impact of the SARS-CoV-2 pandemic on access to interventions for those living with type 1 diabetes and discusses the solutions which have been considered and actioned to ensure ongoing access care.

METHODS

We performed a focussed review of the published literature, and the guidelines for changes that have been effected during the pandemic. We also drew from expert recommendations and information about local practice changes for areas where formal data have not been published.

RESULTS

Evidence based interventions which support the achievement of improved glucose levels and/or reduction in hypoglycaemia include group structured education to support self-management, insulin pump therapy and continuous glucose monitoring. The SARS-CoV-2 pandemic had impacted the ability of diabetes services to deliver these intervention. Multiple adaptations have been put in place - transition to online delivery of education and care, and usage of diabetes technology.

CONCLUSIONS

Although various adaptations have been made during the pandemic that have positively influenced uptake of services, there are many areas of delivery that need immediate improvement in the UK. We recommend a proactive approach in recognising the digital divide and inequity in distribution of these changes and we recommend introducing measures to reduce them.

Radiography of human dry bones: A reflective account with recommendations for practice

INTRODUCTION

This study presents the reflective account of a large-scale radiographic survey of medieval and post-medieval long bones from St Albans, United Kingdom. As a practicing diagnostic radiographer and archaeologist, the author sought to apply experiential learning to generate recommendations for archaeological and forensic radiography practice. The purpose of the imaging was to identify Harris lines for biological stress, however this reflective piece concerns the adaptation of clinical radiographic technique for human dry bones.

METHODS

Imaging took place over five sessions in early 2021 with the assistance of an osteoarchaeologist. Radiography followed standard clinical views (anterior-posterior and medio-lateral) of femora, humeri, radii and tibiae using a digital radiography system. A workplace diary was used to record challenges, solutions and musings related to radiographic technique. The Rolfe, Freshwater and Jasper reflective model was applied to collate and present findings.

RESULTS

A total of 502 radiographs of 426 long bones (92 individuals) were acquired. A multidisciplinary team was found to be essential for correct identification of anatomy, laterality and orientation of remains during the survey. Anterior-posterior views were easiest to achieve, with medio-lateral imaging requiring considerably more effort. Radiolucent sponge supports were necessary, although fragmented remains were often impossible to position accurately. Hands-on experience of human bones improved the author's knowledge and confidence with osteology.

CONCLUSION

Although limited to selective long bones of archaeological context and personal experience, the findings of this study have direct applications for forensic radiography practice. This includes use of a multidisciplinary team, robust workflow with integrated failsafe checks, consistent imaging approach and the application of radiolucent sponge supports.

IMPLICATIONS FOR PRACTICE

Recommendations within this study may contribute towards a comprehensive guide for radiographic technique for human dry bones.

Feasibility of using his bundle pacing with boston scientific generators

Introduction

His bundle pacing (HBP) aims to deliver physiological activation of the ventricles via the native His-Purkinje conduction system. A challenge of HBP is the limited market of implantation tools, pacing leads and specifically designed pacing algorithms.

Purpose

Over the last three years both Medtronic (MDT) and Boston Scientific (BSC) generators have been used for HBP in a large tertiary centre. We examined whether there was any difference between lead parameters and battery longevity depending on the type of manufacturer used.

Methods

Patients implanted with a MDT Select Secure model 3830 lead were included in this retrospective study. Data collected included HBP thresholds (analysed at 1ms pulse width) at implant and at the most recent device check, HBP percentages and battery longevity (months). Battery longevity were calculated by adding duration of follow up and estimated battery life at last follow up.

Results

A total of 31 patients were included for data analysis (58% male and mean age 72 years). 18 patients had MDT generators of which 3 were PPMs, 5 were CRT-Ps and 10 were CRT-Ds. 13 patients had BSC generators of which 5 were PPMs, 5 were CRT-Ps and 3 were CRT-Ds. Mean follow up of the cohort was 12.7±9.02 months.

Mean HBP percentages were 77±37% and 72.2±42.1% for MDT and BSC, respectively (p=0.430). Mean HBP threshold (Volts) at implant was significantly lower with BSC vs MDT (0.85±0.58 vs 1.84±1.06, p=0.01), and similar after follow up (1.01±0.91 vs 1.32±0.73, p=NS). There were no statistically significant differences between mean HBP threshold at implant compared to follow up for both manufacturers.

Interestingly, mean battery longevity for BSC vs MDT generators was significantly higher (136±29.3 vs 90.5±29.1, p<0.001). Longevity was also compared for PPM/CRT-P and CRT-D separately. For PPM/CRT-P, BSC generators had significantly higher longevity as compared to MDT (141.6±33.1 vs 91.6±34.5, p=0.009). This difference was not observed for CRT-Ds between the 2 manufacturers (p=0.068).

Conclusion

Our results suggest HBP with MDT Select Secure 3830 lead is feasible with BSC generators. There is potentially greater battery longevity with BSC compared to MDT generators. Further studies are needed with greater numbers and longer follow up to confirm this finding.

Funding Acknowledgement

Type of funding sources: None.

32 Congenital Arteriovenous Malformation of The Breast Associated with Giant Hairy Naevus: A Case Report

Introduction

An arteriovenous malformation (AVM) is defined as an abnormal connection between arteries and veins, bypassing the capillary system. AVM of the breast is a rare clinical entity, with limited evidence to guide management. We present the case of a congenital AVM of the breast in an otherwise healthy woman, with an interesting presenting complaint.

Case Description

A 38-year-old female presented with a ‘buzzing’ sensation and mastalgia in her left breast. Examination revealed a visible pulsatile linear abnormality with a bruit on auscultation. Duplex ultrasonography demonstrated mixing of the arterial and venous flow, consistent with an AVM. Operative management entailed ultrasound guided identification, ligation and excision of all aneurysmal segments. Histopathologic evaluation demonstrated an AVM with no malignant features. At one year postoperatively, the patient reported complete symptom resolution. Literature review identified nine case reports, including two cases of congenital breast AVM, both treated surgically. Seven cases of iatrogenic AVM were identified, with diagnosis based on duplex ultrasonography and management by surgical ligation in all except one, which resolved spontaneously.

Conclusions

ongenital AVM of the breast is a rare clinical entity. Diagnosis can be established using duplex ultrasonography, while CT and MRI may be useful for preoperative planning. Endovascular management alone is associated with high recurrence rates and surgical excision is the favoured approach where technically feasible without major aesthetic or functional compromise.

Primary, Recall, and Decay Kinetics of SARS-CoV-2 Vaccine Antibody Responses

Studies of two SARS-CoV-2 mRNA vaccines suggested that they yield ∼95% protection from symptomatic infection at least short-term, but important clinical questions remain. It is unclear how vaccine-induced antibody levels quantitatively compare to the wide spectrum induced by natural SARS-CoV-2 infection. Vaccine response kinetics and magnitudes in persons with prior COVID-19 compared to virus-naı̈ve persons are not well-defined. The relative stability of vaccine-induced versus infection-induced antibody levels is unclear. We addressed these issues with longitudinal assessments of vaccinees with and without prior SARS-CoV-2 infection using quantitative enzyme-linked immunosorbent assay (ELISA) of anti-RBD antibodies. SARS-CoV-2-naı̈ve individuals achieved levels similar to mild natural infection after the first vaccination; a second dose generated levels approaching severe natural infection. In persons with prior COVID-19, one dose boosted levels to the high end of severe natural infection even in those who never had robust responses from infection, increasing no further after the second dose. Antiviral neutralizing assessments using a spike-pseudovirus assay revealed that virus-naı̈ve vaccinees did not develop physiologic neutralizing potency until the second dose, while previously infected persons exhibited maximal neutralization after one dose. Finally, antibodies from vaccination waned similarly to natural infection, resulting in an average of ∼90% loss within 90 days. In summary, our findings suggest that two doses are important for quantity and quality of humoral immunity in SARS-CoV-2-naı̈ve persons, while a single dose has maximal effects in those with past infection. Antibodies from vaccination wane with kinetics very similar to that seen after mild natural infection; booster vaccinations will likely be required.

The use of ondansetron for the treatment of nausea in dogs with vestibular syndrome

Background

Vestibular syndrome is often accompanied by nausea. Drugs currently approved for its treatment have been developed to stop vomiting but not nausea. The efficacy of 5-HT₃ receptor antagonists to reduce nausea has been described for chemotherapy, but not for nausea secondary to vestibular disorders.

Methods

Sixteen dogs with vestibular syndrome-associated nausea were included in the open-label, multicentre study. The intensity of nausea-like behaviour was analysed before ondansetron administration (0.5 mg/kg i.v.) and 2 h afterwards, using a validated 5-point-scale. The occurrence and frequency of salivation, lip licking, restlessness, vocalisation, lethargy, and vomiting were assessed.

Results

All dogs initially showed signs of nausea, whereas only 31% showed vomitus. The intensity of nausea was significantly reduced in all dogs (p ≤ 0.0001) 2 h after ondansetron administration, including the clinical signs of nausea analysed in 11 dogs (salivation [p = 0.0078], lip licking [p = 0.0078], restlessness [p = 0.0039], and lethargy [p = 0.0078]) except for vocalisation (p > 0.9999).

Conclusions

The results provide preliminary evidence of the potential benefit of ondansetron in the treatment of nausea, which was present in all examined dogs. Vomiting was only observed in 5 dogs indicating that nausea can occur separately and should not be perceived only as a preceding stimulation of the vomiting centre.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-021-02931-9.

Brief Report: HIV-1 Seroconversion Is Not Associated With Prolonged Rectal Mucosal Inflammation

OBJECTIVE

Determine the impact of HIV-1 seroconversion on inflammatory cytokines in the rectal mucosa.

SETTING

Secondary analysis of data from men who have sex with men and transgender women who participated in a HIV prevention trial Lima, Peru.

METHODS

From July to December 2017, 605 men who have sex with men and transgender women were screened for rectal gonorrhea/chlamydia (GC/CT). Fifty GC/CT-positive cases were randomly selected and matched with 52 GC/CT-negative controls by age and number of receptive anal intercourse partners in the last month. All participants were HIV-negative at baseline and those with GC/CT at baseline and/or follow-up received appropriate antibiotic therapy. Participants underwent sponge collection of rectal secretions for the measurement of inflammatory cytokines (IL-1β, IL-6, IL-8, and TNF-α) and were screened for rectal GC/CT and HIV at baseline, 3 months, and 6 months. Wilcoxon rank-sum tests compared inflammatory cytokine levels between participants diagnosed with HIV during follow-up and persons who remained HIV-negative.

RESULTS

Eight participants were diagnosed with HIV at the 3-month (n = 6) or 6-month (n = 2) visit. The median number of receptive anal intercourse partners in the month before HIV diagnosis was the same for those who acquired HIV and those who did not. There were no significant differences in inflammatory cytokine levels in rectal mucosa between participants who did and did not experience HIV seroconversion at any time point.

CONCLUSIONS

Despite a surge in viral replication during acute infection, findings from this study suggest that there is no prolonged effect of HIV-1 seroconversion on inflammatory cytokine levels in the rectal mucosa.

The effect of myxomatous mitral valve disease severity on packed cell volume in dogs

OBJECTIVES

The aim of this study was to examine whether associations between disease severity and packed cell volume exist in dogs with myxomatous mitral valve disease.

MATERIALS AND METHODS

Data were selected from 289 dogs that had been examined at a research clinic (2004-2017) on multiple occasions (n=1465). American College of Veterinary Internal Medicine stage and echocardiographic measurements were entered in separate multivariable linear mixed effects models with packed cell volume as the dependent variable. Age, breed, sex, weight and blood urea nitrogen concentrations were additionally tested in these analyses to control for patient characteristics.

RESULTS

Packed cell volume (% whole blood) in stages B1 and B2 (B1: 42.62 ±0.27, P=0.001; B2: 41.77± 0.42, P < 0.001) was lower than stage A (44.57 ±0.53). In stage C, packed cell volume was greater than both preclinical stages (C: 43.84 ±0.46). When the administration of loop diuretics was included in statistical models, packed cell volume was inversely related to normalised left ventricular internal diameters (β: -2.37; 95% confidence intervals: -3.49, -1.25; P < 0.001).

CLINICAL SIGNIFICANCE

Dogs with myxomatous mitral valve disease may develop reductions in packed cell volume as their disease progresses. Although this finding was statistically significant at a population level, it should be noted that the differences described are relatively small. This, along with other causes of variation in packed cell volume, means that changes would be challenging to appreciate within individual patients. Plasma volume depletion following diuretic administration may explain why findings differed in stage C.

Investigation of the transforming growth factor-beta 1 signalling pathway as a possible link between hyperphosphataemia and renal fibrosis in feline chronic kidney disease

•

Chronic kidney disease (CKD) is associated with development of hyperphosphataemia.

•

Severity of renal fibrosis has been correlated with degree of hyperphosphataemia.

•

Transforming growth factor-β1 (TGF-β1) is a major pro-fibrotic mediator in CKD.

•

A phosphate restricted diet did not affect urinary active TGF-β1 excretion in cats.

•

Increased extracellular phosphate had no pro-fibrotic effect on feline renal cells.

Chronic kidney disease (CKD) is common in geriatric cats, and is characterised in the majority of cases by tubulointerstitial inflammation and fibrosis. Hyperphosphataemia is a frequent complication of CKD and is independently associated with severity of renal fibrosis and disease progression. Transforming growth factor-beta 1 (TGF-β1) signalling is thought to be a convergent pathway which mediates the progression of renal fibrosis in CKD. The aims of this study were to explore the interaction between increased extracellular phosphate and the TGF-β1 signalling pathway by investigating: (a) the effect of a commercially available, phosphate-restricted, diet on urinary TGF-β1 excretion in cats with CKD; and (b) the role of increased extracellular phosphate in regulating proliferation, apoptosis, and expression of genes related to TGF-β1 signalling and extracellular matrix (ECM) production in feline proximal tubular epithelial cells (FPTEC) and cortical fibroblasts from cats with azotaemic CKD (CKD-FCF).

The dietary intervention study revealed no effect of dietary phosphate restriction on urinary active TGF-β1 excretion after 4–8 weeks (P = 0.98), despite significantly decreasing serum phosphate (P < 0.001). There was no effect of increased growth media phosphate concentration (from 0.95 mM to 2 mM and 3.5 mM) on proliferation (P = 0.99) and apoptotic activity in FPTEC (P = 0.22), or expression of genes related to ECM production and the TGF-β1 signalling pathway in FPTEC and CKD-FCF (P > 0.05). These findings suggest the beneficial effects of dietary phosphate restriction on progression of feline CKD may not occur through modulation of renal TGF-β1 production, and do not support a direct pro-fibrotic effect of increased extracellular phosphate on feline renal cells.

The new age of renal biomarkers: does SDMA solve all of our problems?

Within clinical small animal practice, diagnosis of both chronic kidney disease and acute kidney injury is common. To assess renal function, measurement of glomerular filtration rate is considered the gold standard. Currently, routine tests of kidney function include surrogate markers of glomerular filtration rate such as serum creatinine, and urea, each with their own limitations, whilst urine protein to creatinine ratio gives an indication of glomerular and tubular handling of protein, and urine specific gravity information about urine concentrating ability by the kidney. These parameters are used together with historical and physical examination data to give a diagnosis of kidney disease following which creatinine, proteinuria and blood pressure are used to stage chronic kidney disease and, together with urine output, grade acute kidney injury according to the International Renal Interest Society. However, there has been much concern that creatinine is insensitive when used to indicate early decline in renal function and this has highlighted the need for additional methods of diagnosing and monitoring these patients, with the potential to allow earlier therapeutic intervention. Symmetric dimethylarginine is a novel biomarker, which has been shown to perform as a surrogate marker of glomerular filtration rate in small animals. This article will review current research on symmetric dimethylarginine and the ways in which it may be utilised in small animal practice; current research supports the use of symmetric dimethylarginine as a screening test for detection of early chronic kidney disease according to International Renal Interest Society guidelines, but further research is required in to the usefulness of symmetric dimethylarginine as a tool for monitoring disease and the effect of non-renal influences.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Histiocytic sarcoma in miniature schnauzers: 30 cases

OBJECTIVES

To summarise the clinical presentation and outcomes in a series of miniature schnauzers diagnosed with histiocytic sarcoma.

MATERIALS AND METHODS

Retrospective review of medical records of miniature schnauzers diagnosed with histiocytic sarcoma between 2008 and 2019 at two referral centres in the UK. Signalment, clinical signs at initial presentation, imaging results and clinico- and histopathological findings, treatment type and outcome were recorded. Progression-free survival and overall survival time were calculated.

RESULTS

Thirty dogs were included. Twenty-four of 29 dogs undergoing imaging of the thorax had lung and/or mediastinal involvement. The median overall survival time for dogs that were not euthanased within 3 days of diagnosis was 117 days (range 10 to 790). Three dogs underwent surgery; 13 received treatment with lomustine as a sole therapy - with partial responses documented on imaging in five of six dogs and 11 of 13 showing clinical improvement.

CLINICAL SIGNIFICANCE

Histiocytic sarcoma should be considered as a differential diagnosis for miniature schnauzers with pulmonary masses. Although responses to treatment were common, they were usually short-lived because of the aggressive nature of the disease.

What are the characteristics of the best type 1 diabetes patient education programmes (from diagnosis to long-term care), do they improve outcomes and what is required to make them more effective?

The last 20 years have witnessed a marked change in approaches to the management of type 1 diabetes in the UK. This is exemplified by National Institute of Health and Care Excellence (NICE) guidance which acknowledges that reaching and maintaining target glucose depends on people with type 1 diabetes effectively implementing flexible intensive insulin therapy. The guidance emphasizes that successful self-management requires the acquisition of complex skills and is best achieved by participation in high-quality structured education. Controlled trials and other research have shown that programmes teaching self-management can lower glucose levels while reducing hypoglycaemia, improve psychological outcomes and are highly cost-effective. An important principle of successful programmes is therapeutic education in which learning becomes a partnership between the professional and the person with diabetes who learns to fit diabetes into his/her everyday life. Other recommended elements of programmes include a written curriculum, group teaching by a professional multidisciplinary team and quality assurance. Yet many participants struggle post-course to implement and maintain skills, and overall HbA_1c levels, particularly in the UK, remain far from target. Recent studies have identified the barriers to sustained effective self-management and concluded that even high-quality programmes generally lack critical components. These include incorporating evidence from behaviour change research, exploiting the promise of new technologies in reducing the burden of self-management, and providing structured professional support once people have completed the training. Studies are currently underway to evaluate structured training courses which have added these elements and examine whether they can lower glucose to levels closer to target without impairing quality of life.

The IBD-associated long noncoding RNA IFNG-AS1 regulates the balance between inflammatory and anti-inflammatory cytokine production after T-cell stimulation

The inflammatory bowel diseases (IBD) are a complex set of chronic gastrointestinal inflammatory conditions arising from the interplay of genetic and environmental factors. This study focuses on noncoding RNA transcripts as potential mediators of IBD pathophysiology. One particular gene, interferon γ-antisense 1 (IFNG-AS1), has been consistently observed to be elevated in the intestinal mucosa of patients with actively inflamed IBD versus healthy controls. This study builds on these observations, demonstrating that the second splice variant is specifically altered, and this alteration even stratifies within inflamed patients. With the use of a CRISPR-based overexpression system, IFNG-AS1 was selectively overexpressed directly from its genomic loci in T cells. An unbiased mRNA array on these cells identified a large increase in many inflammatory cytokines and a decrease in anti-inflammatory cytokines after IFNG-AS1 overexpression. Media from T cells overexpressing IFNG-AS1 elicited an inflammatory signaling cascade in primary human peripheral blood mononuclear cells, suggesting the potential functional importance of IFNG-AS1 in IBD pathophysiology. The significance of these results is amplified by studies suggesting that a single-nucleotide polymorphism in IFNG-AS1, rs7134599, was associated with both subtypes of patients with IBD independently of race.NEW & NOTEWORTHY Long noncoding RNAs are an emerging field of inflammatory bowel disease (IBD) research. This study mechanistically analyzes the role of a commonly upregulated gene in IBD and shows IFNG-AS1 as a mediator of an inflammatory signaling cascade.

Working with Insulin, Carbohydrates, Ketones and Exercise to Manage Diabetes (WICKED): evaluation of a self-management course for young people with Type 1 diabetes

AIMS

To evaluate a 5-day self-management education course for young people with Type 1 diabetes and assess its effects on knowledge, self-efficacy, beliefs, distress, self-management behaviours and HbA_1c .

METHODS

This is an evaluation of a structured education course. Young people (aged 16-24 years) with Type 1 diabetes were recruited from three diabetes centres. In the first centre, participants completed self-report measures of knowledge, self-efficacy, positive and negative outcome expectancies, and hypoglycaemic worries at baseline (n=47) and the end of the course (n=42). In two additional centres, participants completed these and other measures assessing self-management behaviours, cognitive adaptation to diabetes and diabetes distress at baseline (n=32), the end of the course (n=27) and 3-month follow-up (n = 27). HbA_1c levels were recorded at baseline (n=79), 6 months (n=77) and 12 months (n=65).

RESULTS

There were statistically significant increases in self-report knowledge, self-efficacy, positive outcome expectancies and self-management behaviours, and a statistically significant decrease in negative outcome expectances, between baseline and the end of the course. There were also statistically significant increases in self-report knowledge, self-efficacy, self-management behaviours and cognitive adaptation to diabetes between baseline and 3-month follow-up. Compared with baseline, HbA_1c levels decreased by a mean (sd) of 5.44 (19.93) mmol/mol (0.48%) at 6 months (P=0.019), and by 5.98 (23.32) mmol/mol (0.54%) at 12 months (P =0.043).

DISCUSSION

The results indicate the potential benefits of a self-management course designed to address the developmental needs and challenges faced by young people with Type 1 diabetes. Further studies with larger numbers and appropriate controls are required to confirm these initial findings.

Characterisation of Crandell-Rees Feline Kidney (CRFK) cells as mesenchymal in phenotype

The Crandell-Rees Feline Kidney Cell (CRFK) is an immortalised cell line derived from the feline kidney that is utilised for the growth of certain vaccinal viruses. Confusion exists as to whether CRFK are epithelial or mesenchymal in phenotype. The aim of this study was to characterise CRFK cells via immunofluorescence, enzyme cytochemistry, western blotting, RT-qPCR for S100A4 and comparison to primary feline proximal tubular epithelial cells (FPTEC) and feline cortical fibroblasts (FCF). CRFK cells were of fusiform morphology and appeared similar to FCF. CRFK expressed the mesenchymal intermediate filament (IF) protein vimentin together with two cell adhesion molecules associated with feline fibroblasts (CD29 and CD44), and lacked expression of the epithelial IF cytokeratin, myogenic IF desmin and endothelial marker von Willebrand factor (vWF). In addition, CRFK did not demonstrate brush border enzyme activity typical of FPTEC. S100A4 gene expression, implicated in both neoplastic transformation and epithelial to mesenchymal transition, was highly upregulated in CRFK in comparison to the primary feline renal cells. CRFK appear phenotypically similar to fibroblasts, rather than tubular epithelial cells, and may have undergone neoplastic transformation or epithelial-to-mesenchymal transition after extensive passaging. This finding may have potential implications for future research utilising this cell line.

A Retrospective Study of Multi-agent Chemotherapy including either Cyclophosphamide or Lomustine as Initial Therapy for Canine High-grade T-cell Lymphoma (2011-2017)

Multi-agent chemotherapy (vincristine, epirubicin and prednisolone) including either cyclophosphamide (CEOP) or lomustine (LEOP) was given as first-line chemotherapy to treatment-naïve canine lymphoma patients with measurable, high grade T-cell lymphoma (HGTCL). All patients responded to either CEOP or LEOP. Toxicity was typical of multi-agent chemotherapy protocols and 25% of dogs receiving lomustine exhibited mild-to-moderate ALT elevation and 29% grade 3 or 4 neutropenia. Median progression-free survival (100 versus 269 days) and overall survival (155 versus 327 days) were significantly higher in patients receiving LEOP compared to CEOP. Overall survival was improved for patients receiving LEOP compared to those receiving CEOP followed by lomustine-based rescue therapy. The results of this retrospective study support further evaluation of lomustine as part of first-line, multi-agent therapy for patients with HGTCL.

Human Vault Nanoparticle Targeted Delivery of Antiretroviral Drugs to Inhibit Human Immunodeficiency Virus Type 1 Infection

"Vaults" are ubiquitously expressed endogenous ribonucleoprotein nanoparticles with potential utility for targeted drug delivery. Here, we show that recombinant human vault nanoparticles are readily engulfed by certain key human peripheral blood mononuclear cells (PBMC), predominately dendritic cells, monocytes/macrophages, and activated T cells. As these cell types are the primary targets for human immunodeficiency virus type 1 (HIV-1) infection, we examined the utility of recombinant human vaults for targeted delivery of antiretroviral drugs. We chemically modified three different antiretroviral drugs, zidovudine, tenofovir, and elvitegravir, for direct conjugation to vaults. Tested in infection assays, drug-conjugated vaults inhibited HIV-1 infection of PBMC with equivalent activity to free drugs, indicating vault delivery and drug release in the cytoplasm of HIV-1-susceptible cells. The ability to deliver functional drugs via vault nanoparticle conjugates suggests their potential utility for targeted drug delivery against HIV-1.

Urinary peptidome analyses for the diagnosis of chronic kidney disease in dogs

Chronic kidney disease (CKD) is clinically important in canine medicine. Current diagnostic tools lack sensitivity for detection of subclinical CKD. The aim of the present study was to evaluate urinary peptidome analysis for diagnosis of CKD in dogs. Capillary electrophoresis coupled to mass spectrometry analysis demonstrated presence of approximately 5400 peptides in dog urine. Comparison of urinary peptide abundance of dogs with and without CKD led to the identification of 133 differentially excreted peptides (adjusted P for each peptide <0.05). Sequence information was obtained for 35 of these peptides. This 35 peptide subset and the total group of 133 peptides were used to construct two predictive models of CKD which were subsequently validated by researchers masked to results in an independent cohort of 20 dogs. Both models diagnosed CKD with an area under the receiver operating characteristic (ROC) curve of 0.88 (95% confidence intervals [CI], 0.72-1.0). Most differentially excreted peptides represented fragments of collagen I, indicating possible association with fibrotic processes in CKD (similar to the equivalent human urinary peptide CKD model, CKD273). This first study of the urinary peptidome in dogs identified peptides that were associated with presence of CKD. Future studies are needed to validate the utility of this model for diagnosis and prediction of progression of canine CKD in a clinical setting.

A multicentre, UK, retrospective, observational study to assess the effectiveness of insulin glargine 300 units/ml in treating people with Type 1 diabetes mellitus in routine clinical practice (SPARTA)

AIM

To conduct an open-label study to provide UK real-world evidence regarding the use of insulin glargine 300 units/ml (U300) in people with Type 1 diabetes mellitus.

METHODS

People with Type 1 diabetes who had been prescribed U300 ≥6 months before data collection and had HbA_1c levels recorded within 3 months prior to U300 (baseline) were included. The primary endpoint was change in HbA_1c from baseline to month 6 after U300 initiation. Other endpoints included number of documented hypoglycaemic and diabetic ketoacidosis episodes, and change in daily basal insulin dose.

RESULTS

A total of 298 people with Type 1 diabetes were included [mean age 42.1 years, mean HbA_1c 79 mmol/mol (9.4%)]. After U300 initiation, the mean reduction in HbA_1c from baseline to month 6 was -4 mmol/mol (-0.4%; P<0.001; n=188). The total daily basal insulin dose at 6 months was 1.3 units higher than at the time of U300 initiation (P<0.001; n=275) but was not significantly different from the prior basal insulin dose. There was no clinically significant difference in weight between baseline and month 6 [mean difference +0.7 kg, 95% CI -0.1, 1.5; P=0.084; n=115). During the 6 months before and after U300 initiation, severe hypoglycaemic episodes were documented for 6/298 and 4/298 participants. Diabetic ketoacidosis episodes requiring Accident and Emergency department visits or hospitalization were documented for 4/298 and 6/298 participants, before and after U300 initiation, respectively.

CONCLUSIONS

In people with Type 1 diabetes, a change in basal insulin to U300 was associated with clinically and statistically significant HbA_1c improvements, without significant changes in basal insulin dose and weight. Documented severe hypoglycaemia episodes and diabetic ketoacidosis requiring Accident and Emergency department visits or hospitalization were low and similar before and after U300 initiation.

Experiences of self-management among young adults with Type 1 diabetes in the context of a structured education programme: a qualitative study

AIMS

To explore the experiences of young adults with regard to self-management of Type 1 diabetes in the context of a structured education programme.

METHODS

Qualitative interviews and focus groups were conducted with young adults attending a structured education course promoting a flexible and self-directed format. Participants attending the structured education courses were recruited using purposive sampling to acquire a broad mix of participants based on age and equal numbers of young men and women. Fifteen interviews were conducted 12 weeks after each course, whilst seven focus groups and observations of the course delivery were conducted at two course sites and were led by nurse/dietitian educators representing two different diabetes centres (paediatric and adult). The interview and focus group data were audio recorded and transcribed, coded, and analysed thematically to identify similarities and differences.

RESULTS

The analysis revealed three themes, 'we're in it together', 'tacit benefits' and 'transitions beyond the structured education programme'. The findings show that structured education programmes can facilitate reflective critical thinking and greater engagement with diabetes self-management if they: a) foster maximal learning from fellow participants to decrease feelings of isolation, b) maximize engagement during the course by delivering the content in a flexible manner, and c) recognize the social and emotional needs of young adults.

CONCLUSION

Structured education courses can result in improved critical thinking and engagement with diabetes self-management by empowering young adults through a flexible and self-directed learning style that encourages peer group discussion.

Comparative Assessment of Small and Large Intestine Biopsies for Ex Vivo HIV-1 Pathogenesis Studies

Ex vivo mucosal explants have become a mainstay of HIV-1 studies using human tissue. In this study, we examine the baseline phenotypic and virologic differences between biopsies derived from the small intestine (SI) and large intestine (LI) for use in ex vivo explant studies. To do this, we collected endoscopic mucosal biopsies from both SI and LI from the same healthy, HIV-seronegative participants. Mucosal mononuclear cell phenotypes and quantity were compared using flow cytometry. Comparative HIV-1 infectibility of the explants was assessed using an ex vivo explant HIV-1 infection assay. We found that all biopsies had similar numbers of T cells per biopsy. While the percentage of CD4⁺ T cells from SI biopsies expressed significantly more activation markers (CD38, HLA-DR) and HIV coreceptors (CXCR4, CCR5), the absolute numbers of activated CD4⁺ T cells were similar between both sites. LI explants, however, supported more efficient HIV-1 infection, as evidenced by earlier rise in p24 accumulation and greater percent of infected explants at limiting infectious doses. These results suggest that explants from LI biopsies support more efficient HIV-1 infection than SI biopsies, despite similar numbers of available, activated HIV-1 target cells. These findings highlight important differences in LI and SI explants, which must be considered in designing and interpreting ex vivo HIV-1 infection studies, and suggest that factors within the tissue other than target cell number and activation state may play a role in regulating HIV-1 infection.

Cell specific microvesicles vary with season and disease predisposition in healthy and previously laminitic ponies

Microvesicles are small (up to 1 μm) vesicles found in plasma and other bodily fluids. They are recognised as part of the normal system of inter-cellular communication but altered numbers are also used as biomarkers of disease. Microvesicles have not been studied in detail in the horse but may be relevant to diseases such as laminitis. Identification of equine cell specific microvesicles was performed by developing a panel of cross reactive antibodies to use in flow cytometry to detect microvesicles of platelet, leucocyte and endothelial origin in plasma from healthy ponies and those predisposed to laminitis. The total number and proportion of microvesicles from the different cell types varied with season and there were more annexin V positive endothelial MV in non laminitic ponies compared to previously laminitic ponies. Development of this antibody panel and the technique for measuring microvesicles in the horse opens a new field for further investigation of these important structures in equine health and disease.

Human Semen or Seminal Plasma Does Not Enhance HIV-1BaL Ex Vivo Infection of Human Colonic Explants

To determine whether human whole semen (WS) and seminal plasma (SP) either previously frozen or freshly acquired altered ex vivo infectibility of human colonic explants or was associated with histology or toxicity changes, which may influence mucosal HIV-1 transmission in vivo. Pooled human semen samples were freshly obtained from study volunteers (never frozen) and from commercial sources (frozen/thawed). Endoscopically acquired rectal biopsies were evaluated for toxicity following titered ex vivo WS/SP exposure by histological grading and by MTT assay. The ex vivo HIV-1 biopsy challenge model was used to evaluate effects of exposure to either previously frozen or freshly acquired WS/SP on HIVBaL infectibility at a range of viral inocula (104-100 TCID50). To evaluate the effects at lower viral inocula of HIV-1 (10-2-102), experiments in the presence or absence of WS/SP were also performed utilizing TZM-bl cells. MTT assays and histological scoring demonstrated no tissue degradation of biopsies when exposed for 2 h to concentrations of 10% or 100% of either fresh or previously frozen WS/SP. Ex vivo biopsy HIV-1 challenge experiments showed no differences in the presence of freshly acquired or previously frozen/thawed WS/SP compared with control; no differences were seen with lower infectious titers on TZM-bl cells. Within the limits of assay sensitivity and variability, these data show no toxicity or significant enhancement of HIV-1 infectibility of human rectal mucosa using the colorectal explant model with either pooled fresh or frozen/thawed nonautologous human semen.

Transfection of Human Breast Epithelial Cells with Foreign Dna Using Different Transfecting Techniques

The introduction of DNA into eukaryotic cells is a powerful technique for the study of gene regulation. This requires both a technique by which genes can efficiently be introduced into cells and a recipient cell representative of the tissue under study. We have utilized a spontaneously immortalized human breast epithelial cell line, CMF-10, which is phenotypically normal for introducing a neomycin-resistant gene contained in the plasmid Homer 6 (pHo6). Three different transfection methods were tested: calcium phosphate, with and without glycerol shock, using as control NIH/3T3 cells, and strontium phosphate and electroporation. In MCF-10 cells the efficiency of calcium phosphate mediated DNA transfection, which was measured as the number of colonies growing in neomycin-containing medium, was 21 and 140 fold higher than in MCF-10 cells transfected by electroporation and strontium phosphate methods, respectively. Glycerol shock enhanced three fold transfection efficiencies. NIH/3T3 transfected cells by calcium phosphate method showed a transfection efficiency similar to that of MCF-10 cells, however, glycerol shock did not improve the efficiency. These studies revealed that calcium phosphate combined with glycerol shock is the most efficient technique for transfection of genomic DNA into human breast epithelial cells.

UK families with children with rare chromosome disorders: Changing experiences of diagnosis and counselling (2003-2013)

The latest United Kingdom (UK) strategy for rare diseases emphasises the need to empower affected populations to improve diagnosis, intervention, and coordination of care. Families who have a child with a rare chromosome disorder (RCD) are a challenging group to include. We report the findings of 2 large-scale surveys, undertaken by the UK RCD Support Group Unique, of these families' experiences over a 10-year period. Seven stages of the patient journey were examined. From pre-testing, through diagnosis, genetics consultation, clinical follow-up and peer support. Overall, 1158 families replied; 36.4% response rate (2003) and 53.6% (2013). Analysis of responses identifies significant differences (P < .001) over time with a decrease in results reported face to face (76%-62%), doubling by telephone (12%-22%), improved explanation of chromosome disorder (57%-75%), and increased signposting to peer support group (34%-62%). However, conduct of the consultation raises a number of important questions. Overall, 28 aspects of the patient journey are recognised as requiring improvement; only 12/28 are currently incorporated in UK service specifications. Involvement of RCD families has identified key service improvements. This approach can empower those affected by such extremely rare disorders, and also enable professionals to design improved services in partnership with "expert families." Further surveys are planned.

Characterisation of feline renal cortical fibroblast cultures and their transcriptional response to transforming growth factor β1

Background

Chronic kidney disease (CKD) is common in geriatric cats, and the most prevalent pathology is chronic tubulointerstitial inflammation and fibrosis. The cell type predominantly responsible for the production of extra-cellular matrix in renal fibrosis is the myofibroblast, and fibroblast to myofibroblast differentiation is probably a crucial event. The cytokine TGF-β1 is reportedly the most important regulator of myofibroblastic differentiation in other species. The aim of this study was to isolate and characterise renal fibroblasts from cadaverous kidney tissue of cats with and without CKD, and to investigate the transcriptional response to TGF-β1.

Results

Cortical fibroblast cultures were successfully established from the kidney tissue of cats with normal kidney function (FCF) and cats with chronic kidney disease (CKD-FCF). Both cell types expressed the mesenchymal markers vimentin, CD44 and CD29, and were negative for the epithelial marker cytokeratin, mesangial cell marker desmin and endothelial cell marker vWF. Only CKD-FCF expressed VCAM-1, a cell marker associated with inflammation. Incubation with TGF-β1 (0–10 ng/ml) induced a concentration dependent change in cell morphology, and upregulation of myofibroblast marker gene α-SMA expression alongside collagen 1α1, fibronectin, TGF-β1 and CTGF mRNA. These changes were blocked by the TGF-β1 receptor 1 antagonist SB431542 (5 μM).

Conclusions

FCF and CKD-FCF can be cultured via a simple method and represent a model for the investigation of the progression of fibrosis in feline CKD. The findings of this study suggest TGF-β1 may be involved in fibroblast-myofibroblast transition in feline CKD, as in other species.

Calcitonin Response to Naturally Occurring Ionized Hypercalcemia in Cats with Chronic Kidney Disease

Background

Hypercalcemia is commonly associated with chronic kidney disease (CKD) in cats.

Objectives

To explore the calcitonin response to naturally occurring ionized hypercalcemia in cats with azotemic CKD, and to assess the relationship of plasma calcitonin with ionized calcium, alkaline phosphatase (ALP), and urinary calcium excretion.

Animals

Thirty‐three client‐owned cats with azotemic CKD and ionized hypercalcemia from first opinion practice.

Methods

Cohort study. Calcitonin was measured with an immunoradiometric assay in heparinized plasma. Simple correlations were assessed with Kendall's rank correlation, and the within‐subject correlations of calcitonin with ionized calcium and other clinicopathological variables were calculated with a bivariate linear mixed effects model.

Results

Calcitonin concentrations above the lower limit of detection (>1.2 pg/mL; range, 1.7–87.2 pg/mL) were observed in 11 of 33 hypercalcemic cats (responders). Blood ionized calcium concentration did not differ significantly between responders (median, 1.59 [1.46, 1.66] mmol/L) and nonresponders (median, 1.48 [1.43, 1.65] mmol/L; P = 0.22). No evidence was found for calcitonin and ionized calcium to correlate between cats (τ_b = 0.14; P = 0.31; n = 33), but significant positive correlation was evident within individual responders over time (within‐subject correlation coefficient [r_within], 0.83; 95% confidence interval [CI], 0.63–0.92). Calcitonin correlated negatively over time with plasma ALP (r_within, −0.55; 95% CI, −0.79 to −0.16).

Conclusions and Clinical Importance

Calcitonin does not appear to have an important role in calcium metabolism in cats with CKD.