The potential impact of post-COVID symptoms in the healthcare sector

BACKGROUND

The phenomenon of post-COVID syndrome (PCS) is evolving from an abstract array of non-specific symptoms to an identifiable clinical entity of variable severity. Its frequency and persistence have implications for service delivery and workforce planning.

AIMS

This study was aimed to assess the prevalence of symptoms consistent with PCS and the subjective degree of recovery in a cohort of healthcare workers, focusing on those who have returned to work.

METHODS

A study population of 1176 was surveyed when attending for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody testing. Two sub-groups were identified: those with known (i.e. diagnosed on PCR testing) and assumed (i.e. antibody evidence of previous infection) SARs-CoV-2 infection, at least 12 weeks prior to the study. Each group was asked about their subjective degree of recovery and the nature of their persistent symptoms. Results were analysed via excel and SPSS.

RESULTS

In total, 144 employees showed PCR evidence of previous infection, with 139 of these being infected at least 12 weeks prior to the study. Of these 139, only 19% (n = 26) reported feeling 100% recovered, and 71% reported persistent symptoms. Of those with assumed SARS-CoV-2 infection (n = 78), 32 (41%) were truly asymptomatic since the commencement of the pandemic, while 46 (59%) described symptoms suggestive of possible infection at least 12 weeks prior to the study. Of this latter group, 23% (n = 18) also reported residual symptoms.

CONCLUSIONS

PCS is prevalent among this group, including those not previously diagnosed with COVID-19. Its' frequency and duration present challenges to employers with regards to the management of work availability and performance.

Prognostic gene expression signature for high-grade serous ovarian cancer

BACKGROUND

Median overall survival (OS) for women with high-grade serous ovarian cancer (HGSOC) is ∼4 years, yet survival varies widely between patients. There are no well-established, gene expression signatures associated with prognosis. The aim of this study was to develop a robust prognostic signature for OS in patients with HGSOC.

PATIENTS AND METHODS

Expression of 513 genes, selected from a meta-analysis of 1455 tumours and other candidates, was measured using NanoString technology from formalin-fixed paraffin-embedded tumour tissue collected from 3769 women with HGSOC from multiple studies. Elastic net regularization for survival analysis was applied to develop a prognostic model for 5-year OS, trained on 2702 tumours from 15 studies and evaluated on an independent set of 1067 tumours from six studies.

RESULTS

Expression levels of 276 genes were associated with OS (false discovery rate < 0.05) in covariate-adjusted single-gene analyses. The top five genes were TAP1, ZFHX4, CXCL9, FBN1 and PTGER3 (P < 0.001). The best performing prognostic signature included 101 genes enriched in pathways with treatment implications. Each gain of one standard deviation in the gene expression score conferred a greater than twofold increase in risk of death [hazard ratio (HR) 2.35, 95% confidence interval (CI) 2.02-2.71; P < 0.001]. Median survival [HR (95% CI)] by gene expression score quintile was 9.5 (8.3 to -), 5.4 (4.6-7.0), 3.8 (3.3-4.6), 3.2 (2.9-3.7) and 2.3 (2.1-2.6) years.

CONCLUSION

The OTTA-SPOT (Ovarian Tumor Tissue Analysis consortium - Stratified Prognosis of Ovarian Tumours) gene expression signature may improve risk stratification in clinical trials by identifying patients who are least likely to achieve 5-year survival. The identified novel genes associated with the outcome may also yield opportunities for the development of targeted therapeutic approaches.

Correction: Safety and utility of image-guided research biopsies in relapsed high-grade serous ovarian carcinoma-experience of the BriTROC consortium

This article was originally published under a CC BY NC SA License, but has now been made available under a CC BY 4.0 License.

Safety and utility of image-guided research biopsies in relapsed high-grade serous ovarian carcinoma-experience of the BriTROC consortium

BACKGROUND

Investigating tumour evolution and acquired chemotherapy resistance requires analysis of sequential tumour material. We describe the feasibility of obtaining research biopsies in women with relapsed ovarian high-grade serous carcinoma (HGSC).

METHODS

Women with relapsed ovarian HGSC underwent either image-guided biopsy or intra-operative biopsy during secondary debulking, and samples were fixed in methanol-based fixative. Tagged-amplicon sequencing was performed on biopsy DNA.

RESULTS

We screened 519 patients in order to enrol 220. Two hundred and two patients underwent successful biopsy, 118 of which were image-guided. There were 22 study-related adverse events (AE) in the image-guided biopsies, all grades 1 and 2; pain was the commonest AE. There were pre-specified significant AE in 3/118 biopsies (2.5%). 87% biopsies were fit-for-purpose for genomic analyses. Median DNA yield was 2.87 μg, and was higher in biopsies utilising 14 G or 16 G needles compared to 18 G. TP53 mutations were identified in 94.4% patients.

CONCLUSIONS

Obtaining tumour biopsies for research in relapsed HGSC is safe and feasible. Adverse events are rare. The large majority of biopsies yield sufficient DNA for genomic analyses-we recommend use of larger gauge needles and methanol fixation for such biopsies, as DNA yields are higher but with no increase in AEs.

Methanol-based fixation is superior to buffered formalin for next-generation sequencing of DNA from clinical cancer samples

BACKGROUND

Next-generation sequencing (NGS) of tumour samples is a critical component of personalised cancer treatment, but it requires high-quality DNA samples. Routine neutral-buffered formalin (NBF) fixation has detrimental effects on nucleic acids, causing low yields, as well as fragmentation and DNA base changes, leading to significant artefacts.

PATIENTS AND METHODS

We have carried out a detailed comparison of DNA quality from matched samples isolated from high-grade serous ovarian cancers from 16 patients fixed in methanol and NBF. These experiments use tumour fragments and mock biopsies to simulate routine practice, ensuring that results are applicable to standard clinical biopsies.

RESULTS

Using matched snap-frozen tissue as gold standard comparator, we show that methanol-based fixation has significant benefits over NBF, with greater DNA yield, longer fragment size and more accurate copy-number calling using shallow whole-genome sequencing (WGS). These data also provide a new approach to understand and quantify artefactual effects of fixation using non-negative matrix factorisation to analyse mutational spectra from targeted and WGS data.

CONCLUSION

We strongly recommend the adoption of methanol fixation for sample collection strategies in new clinical trials. This approach is immediately available, is logistically simple and can offer cheaper and more reliable mutation calling than traditional NBF fixation.

SU-E-J-58: Patient-Specific Biomechanical Head and Neck Models for Interfraction Dose Accumulation

PURPOSE

In this abstract, we discuss a biomechanical head and neck model that will be able to represent patient setup variations as well as physiologic changes and subsequently enable dose calculations on the deformed anatomy.

METHODS

We selected Multi Pose MRI as the imaging modality to aid in model development and validation. The MRI data allowed us to build a biomechanically predictive model that will enable accurate estimation of tumor position when seeded with CT data alone. The soft tissue contrast and lack of ionizing radiation when using MRI enabled us to acquire extensive imaging datasets with a suitable variety of head pose variations. These poses were selected to encompass the clinical positioning variations so that the resulting model will accurately reflect internal organ motion and deformation. All images were acquired using an 8-channel, 1.5T research MRI system in radiology. The imaging volume extended from about T3(upper thoracic vertebrae) to the top of the head, thereby covering the entire head and neck. Model components included: muscles, skeletal bones, lymph nodes, fat tissues, and organs such as salivary glands, tendons, andligaments. At first, one MRI image dataset was selected as the reference image. The biometric properties (length, volume, mass, shape), hinge constraints of the bones, and the biomechanical properties of each of the anatomies were estimated using MRIs acquired at different head and neck poses.

RESULTS

The model's ability to represent different head and neck postures can be illustrated by observing the internal tissue deformations andthe model's ability to represent different postures.

CONCLUSIONS

Results show that the biomechanical model was able to simulate different poses that may be exhibited during interfraction patient setup variations and intrafraction patient motion. Future work would focus on integrating dose calculations on the deforming model and validating the model deformations.

SU-E-J-192: Static Breath-Hold MRI Based Measurement of Change in Pulmonary Function Following a Course of Radiation Therapy

PURPOSE

Radiation Therapy (RT) induced pulmonary function change may depend on the location, underlying function of that lung prior to radiations, radiation dose/fractionation and other factors. We propose to evaluate the radiation induced pulmonary function change using static breath-hold MRI scans with vascular information and 3D deformable image registration which can provide pulmonary function relative to RT dose on a regional basis.

METHODS

A MRI scan pair near the end of inhale and near the end of exhale with breath hold were acquired for one lung cancer patient before RT and 6 months after RT. The patient was treated with SBRT with 55 Gy to PTVs in the right and the left lung respectively. B-spline based vesselness preserving image registration algorithm was applied to register the MRI pair for the calculation of local lung expansion as a measurement of regional pulmonary function (PF). The PF maps before RT and after RT were then mapped to the planning CT using the same algorithm tuned for MRI-CT registration. The pulmonary function change was calculated via the PF ratio between two MRI pairs.

RESULTS

Strong spatial correlation was found between the irradiated lung region and the region with greatly decreased PF. Based on dose and PFC distribution, no strong determinant factor was found for PF lost in the left lung while the right lung shows that all the lung tissue receiving dose larger than 28 Gy will have a decreased PF.

CONCLUSIONS

We demonstrated a method that uses static breath-hold MRI based lung imaging to evaluate radiation induced pulmonary function change which can be applied to study the dose and the pulmonary function change in a regional basis. This work is supported by NIH grant support 1R21CA144063.

Associations between leptin and adiponectin receptor upregulation, visceral obesity and tumour stage in oesophageal and junctional adenocarcinoma

BACKGROUND

Obesity is associated with oesophageal adenocarcinoma, but mechanisms linking fat and carcinogenesis remain poorly understood. Altered circulating adipocytokines may be important. This study aimed to identify pathways through which visceral fat impacts on tumour biology.

METHODS

Seventy-five patients with oesophageal adenocarcinoma underwent anthropometric and radiological assessment of obesity. Expression of leptin receptor (ObR) and adiponectin receptors 1 and 2 (AdipR1, AdipR2) was quantified by real-time reverse transcriptase-polymerase chain reaction. The human oesophageal adenocarcinoma cell line OE33 was used as the calibrator sample.

RESULTS

Ninety-one per cent of tumours expressed ObR, 95 per cent expressed AdipR1 and 100 per cent expressed AdipR2. Relative expression of ObR was upregulated in 67 per cent, and AdipR1 and AdipR2 were downregulated in 55 and 68 per cent respectively, relative to the calibrator sample. Upregulated ObR and AdipR2 expression was significantly associated with anthropometric and radiological measures of obesity. Upregulated ObR was associated with advanced tumour and node category (P = 0.036 and P = 0.025 respectively), and upregulated AdipR2 with nodal involvement (P = 0.037).

CONCLUSION

Obesity is associated with upregulated ObR and AdipR2 expression in oesophageal adenocarcinoma. The association of ObR and AdipR2 with tumour stage suggest that pathways involving adipocytokines affect tumour biology.

Is Metabolic Syndrome and Central Obesity Relevent to Biology and Progression of Postmenopausal Breast Cancer?

Introduction: Obesity isassociated with both an increased risk of postmenopausal breast cancer and increased mortality rates. The mechanism is unclear, and central (visceral) obesity, insulin resistance, altered sex steroids, and altered adipokines, are mooted as possible factors. These features may cluster in the so-called Metabolic Syndrome (MetS), and the focus of this study was to systematically relate MetS to standard clinicopathological indices of breast cancer.Methods: Postmenopausal women with newly diagnosed breast cancer (n=105) were prospectively recruited. A detailed clinical and dietary history was performed, as well as body composition analysis, metabolic screen, and plasma measurement of adipokines and inflammatory markers. MetS was defined according to the International Diabetes Federation definition.Results: One hundred and five patients were recruited, the median age was 68 years (40-94) and the mean BMI was 28.3 ± 5.2 kg/m2, with 87% of patients centrally obese. MetS was diagnosed in 39% of patients, and was significantly (p&lt;0.005) associated with 13cm greater waist circumference, higher total and trunk fat mass and increased inflammation with CRP levels almost double for MetS patietns compared to non MetS (10.3 ± 2.7 V's 5.8 ± 1.0 mg/L; p=0.084).Patients with later pathological stage (II- IV) were significantly more likely to be obese (BMI) (45% Vs 16%; p=0.007), centrally obese (waist circumference) (94% Vs 72%; p=0.009), hyperglycaemic (31% Vs 12%; p=0.047), hyperinsulinaemia (19% Vs 0; p=0.026) and 51% had MetS compared to 12% for early stage disease (Path stage 0-I). Patients with node positive disease were significantly more likely to be hyperinsulaemic (22% V's 5%; p=0.030) and have MetS (50% V's 30%; p=0.028) than node negative disease.MetS was not associated with hormone receptor status or serum levels of oestradiol, progesterone, testosterone, or SHBG levels. However, SHBG levels decreased with obesity (p=0.002) and as the number of features of MetS increased (0 features: 87 ± 15.8 compared to 5 features: 32 ±2.7; p=0.003). Insulin levels increased with obesity (p=0.006), and with increasing number of features of MetS.Discussion: MetS and central obesity are common in Irish postmenopausal breast cancer patients. MetS appears to be associated with aggressive tumour biology, and this may have significance in preventive and novel treatment approaches.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1051.

Single-dose adjustment versus no adjustment of warfarin in stably anticoagulated patients with an occasional international normalized ratio (INR) out of range

BACKGROUND

Well-controlled patients on warfarin may still have occasional International Normalized Ratios (INRs) outside the therapeutic range. It is unclear whether there is any benefit of a single-dose correction in this situation.

AIM

To evaluate whether patients with very stable INR results should continue with the maintenance dose of warfarin without a single-dose correction, even when the result unexpectedly is moderately below or above the therapeutic range.

METHODS

A) We reviewed retrospectively 364 patients with unchanged maintenance dose for at least 6 months and an occasional INR outside the therapeutic range regarding decision on dosing and the effect on the next INR. B) We randomized 160 patients with at least 3 months of unchanged maintenance dose, an occasional INR deviating to a minimum of 1.5 or a maximum of 4.4 and unexplained or temporary, removable cause to a single-dose Change or No change. Follow-up INRs and telephone interviews were obtained after 2 weeks.

RESULTS

A) Retrospectively, the proportion of follow-up INRs outside the therapeutic range was 29.9% after No change, 27.1% after Increased dose and 25.7% after Skipped/reduced dose. However, the decision on No change was mainly taken in case of minimal INR deviations. B) Forty-eight (60%) of the patients randomized to Change were within the therapeutic range at follow-up versus 45 (56%) of those with No change, odds ratio 1.17 (95% confidence interval 0.59-2.30). For baseline INRs deviating down to 1.6 or up to 3.6 (therapeutic range, INR 2.0-3.0) the 2-week INRs did not differ between the groups.

CONCLUSION

Our results suggest only a small or no difference between the two managements of an occasional INR out of range in terms of the 2-week follow-up INR. In stable patients on warfarin with an occasional INR outside the therapeutic range it seems reasonable to continue with the same dose without a single-dose change and perform a repeat test in about 2 weeks. (ClinicalTrials.gov number, NCT00814177.).

Enhanced sensitivity of insulin-resistant adipocytes to vanadate is associated with oxidative stress and decreased reduction of vanadate (+5) to vanadyl (+4)

Vanadate (sodium orthovanadate), an inhibitor of phosphotyrosine phosphatases (PTPs), mimics many of the metabolic actions of insulin in vitro and in vivo. The potential of vanadate to stimulate glucose transport independent of the early steps in insulin signaling prompted us to test its effectiveness in an in vitro model of insulin resistance. In primary rat adipocytes cultured for 18 h in the presence of high glucose (15 mm) and insulin (10(-7) m), sensitivity to insulin-stimulated glucose transport was decreased. In contrast, there was a paradoxical enhanced sensitivity to vanadate of the insulin-resistant cells (EC(50) for control, 325 +/- 7.5 microm; EC(50) for insulin-resistant, 171 +/- 32 microm; p < 0.002). Enhanced sensitivity was also present for vanadate stimulation of insulin receptor kinase activity and autophosphorylation and Akt/protein kinase B Ser-473 phosphorylation consistent with more effective PTP inhibition in the resistant cells. Investigation of this phenomenon revealed that 1) depletion of GSH with buthionine sulfoximine reproduced the enhanced sensitivity to vanadate while preincubation of resistant cells with N-acetylcysteine (NAC) prevented it, 2) intracellular GSH was decreased in resistant cells and normalized by NAC, 3) exposure to high glucose and insulin induced an increase in reactive oxygen species, which was prevented by NAC, 4) EPR (electron paramagnetic resonance) spectroscopy showed a decreased amount of vanadyl (+4) in resistant and buthionine sulfoximine-treated cells, which correlated with decreased GSH and increased vanadate sensitivity, while total vanadium uptake was not altered, and 5) inhibition of recombinant PTP1B in vitro was more sensitive to vanadate (+5) than vanadyl (+4). In conclusion, the paradoxical increased sensitivity to vanadate in hyperglycemia-induced insulin resistant adipocytes is due to oxidative stress and decreased reduction of vanadate (+5) to vanadyl (+4). Thus, sensitivity of PTP inhibition and glucose transport to vanadate is regulated by cellular redox state.

Successful control of Clostridium difficile infection in an elderly care unit through use of a restrictive antibiotic policy

Toxin-producing Clostridium difficile is the commonest bacterial cause of nosocomial diarrhoea and is a well recognized cause of hospital outbreaks in elderly care units. High C. difficile disease rates have been associated with the use of broad-spectrum antibiotics, especially cephalosporins. An outbreak of C. difficile infection in the elderly care unit at Gloucestershire Royal NHS Trust continued despite increased ward cleaning and strict implementation of infection control measures. A restrictive antibiotic policy that would maintain colonization resistance in the gastrointestinal tract was introduced throughout this unit. Patients admitted with suspected infection were prescribed intravenous (i.v.) benzylpenicillin 1.2-1.8 g every 6 h to cover streptococcal infections and i.v. trimethoprim 200 mg twice daily to cover urinary tract pathogens and Haemophilus influenzae. If the patient had septic shock a single iv dose of gentamicin was given (120-180 mg) to cover more resistant gram-negative bacilli. The following were monitored before and after the policy change. The number of cases of C. difficile toxin-positive diarrhoea; cefuroxime and total antibiotic use on the elderly care wards; patient mortality rates; and length of hospital stay: two hundred and fifty-two and 234 patients respectively with a discharge diagnosis of infection were admitted before and after the antibiotic policy change. Mortality rates and length of hospital stay were unchanged. Cefuroxime prescribing and total antibiotic prescribing costs fell by 5150 pounds sterling and 8622 pounds sterling respectively in the 7 month period after the change. Thirty-seven cases of C. difficile diarrhoea occurred in the period before and 16 in the period after the policy change. The incidence of C. difficile diarrhoea and of cefuroxime use has remained low since then. The use of narrow-spectrum antibiotics for hospital treatment of community-acquired infections in the elderly should be encouraged. Outbreaks of C. difficile diarrhoea should be managed with the combined approach of infection control and strict antibiotic policies.

Effects of cold exposure on rat adrenal tyrosine hydroxylase: an analysis of RNA, protein, enzyme activity, and cofactor levels

Long-term cold exposure (5-7 days) is known to induce concomitant increases in the levels of adrenomedullary tyrosine hydroxylase (TH) RNA, protein, and enzyme activity. In this report, we compare the time courses of these changes and investigate the effects of cold exposure on the levels of biopterin, the cofactor required for tyrosine hydroxylation. After only 1 h of cold exposure, TH mRNA abundance increased 71% compared with nonstressed controls. Increases in total cellular TH RNA levels were maximal (threefold over control values) within 3-6 h of cold exposure and remained elevated throughout the duration of the experiment (72 h). TH protein levels increased rapidly after 24 h of cold exposure and reached a maximal value threefold above that of controls at 48-72 h. Despite the relatively rapid and large elevations in TH RNA and protein content, only modest increases in TH activity were detected during the initial 48 h of cold exposure. Adrenomedullary biopterin increased rapidly after the onset of cold exposure, rising to a level approximately twofold that of the nonstressed controls at 24 h, and remained at this level throughout the duration of the stress period. Taken together, the results of this time course study indicate that cold-induced alterations in adrenal TH activity are mediated by multiple cellular control mechanisms, which may include pre- and posttranslational regulation. Our findings also suggest that cold stress-induced increases in the levels of the TH cofactor may represent another key event in the sympathoadrenal system's response to cold stress.

Guanosine triphosphate cyclohydrolase I deficiency: early diagnosis by routine urine pteridine screening

A deficiency of hepatic guanosine triphosphate cyclohydrolase I is reported in a 4-month-old infant in whom positive results on a Guthrie phenylketonuria test in the neonatal period were found. Because of the significantly elevated serum phenylalanine levels a diagnosis of classical phenylketonuria was made, and dietary therapy was started. Urinary pteridine screening for cofactor variants, however, revealed extremely low levels of both neopterin and biopterin. This suggested the possibility of guanosine triphosphate cyclohydrolase I deficiency and led to additional confirmatory assays. Repeat urine, serum, and CSF pteridine profiles, combined with tetrahydrobiopterin-loading studies and the assay of guanosine triphosphate cyclohydrolase I activity in a liver biopsy, confirmed the defect. It is significant to note that the diagnosis was made before the onset of major clinical symptoms. This case illustrates the need for routine cofactor variant screening of all infants in whom hyperphenylalaninemia is diagnosed in the neonatal period.