PURA-Related Developmental and Epileptic Encephalopathy: Phenotypic and Genotypic Spectrum

BACKGROUND AND OBJECTIVES

Purine-rich element-binding protein A (PURA) gene encodes Pur-α, a conserved protein essential for normal postnatal brain development. Recently, a PURA syndrome characterized by intellectual disability, hypotonia, epilepsy, and dysmorphic features was suggested. The aim of this study was to define and expand the phenotypic spectrum of PURA syndrome by collecting data, including EEG, from a large cohort of affected patients.

METHODS

Data on unpublished and published cases were collected through the PURA Syndrome Foundation and the literature. Data on clinical, genetic, neuroimaging, and neurophysiologic features were obtained.

RESULTS

A cohort of 142 patients was included. Characteristics of the PURA syndrome included neonatal hypotonia, feeding difficulties, and respiratory distress. Sixty percent of the patients developed epilepsy with myoclonic, generalized tonic-clonic, focal seizures, and/or epileptic spasms. EEG showed generalized, multifocal, or focal epileptic abnormalities. Lennox-Gastaut was the most common epilepsy syndrome. Drug refractoriness was common: 33.3% achieved seizure freedom. We found 97 pathogenic variants in PURA without any clear genotype-phenotype associations.

DISCUSSION

The PURA syndrome presents with a developmental and epileptic encephalopathy with characteristics recognizable from neonatal age, which should prompt genetic screening. Sixty percent have drug-resistant epilepsy with focal or generalized seizures. We collected more than 90 pathogenic variants without observing overt genotype-phenotype associations.

An updated report on the incidence and epidemiological trends of keratinocyte cancers in the United Kingdom 2013-2018

Introduction

The most common cancers in the UK are keratinocyte cancers (KCs): the combined term for basal cell carcinomas (BCCs) and cutaneous squamous cell carcinomas (cSCCs). Registration of KC is challenging due to high numbers and multiplicity of tumours per person.

Methods

We provide an updated report on the descriptive epidemiology of trends in KC incidence for the resident populations of UK countries (England, Northern Ireland, Scotland and Wales) using population-based cancer registry and pathology report data, 2013-18.

Results

Substantial increases in cSCC incidence in England, Scotland and Northern Ireland can be detected for the period of 2013-18, and the incidence of cSCC also increased in Wales from 2016 to 2018. In contrast, however, the pattern of annual change in the incidence of BCC across the nations differs. In England, the incidence of BCC declined slightly from 2016 to 2018, however, the overall trend across 2013-18 is not statistically significant. In Scotland, the incidence of BCC shows some variability, declining in 2017 before increasing in 2018, and the overall trend across 2013-18 was also not statistically significant. In Northern Ireland, the incidence of BCC increased significantly over the study period, and in Wales, the incidence of BCC increased from 2016 to 2018. One in five people will develop non-melanoma skin cancers (NMSC) in their lifetime in England. This estimate is much higher than the lifetime risk of melanoma (1 in 36 males and 1 in 47 females born after 1960 in the UK), which further highlights the burden of the disease and importance of early prevention strategies.

Conclusions

We highlight how common these tumours are by publishing the first ever lifetime incidence of NMSC. Additionally, the first time reporting of the age standardised incidence of KC in Wales further confirms the scale of the disease burden posed by these cancers in the UK. With approximately one in five people developing NMSC in their lifetime, optimisation of skin cancer prevention, management and research are essential.

Comparative analysis of brain in relation to the body length and weight of common carp (Cyprinus carpio) in captive (hatchery) and wild (river system) populations

Cyprinus carpio is the member of family cyprinidae commonly called common carp. This study was aimed to find out the comparison of brain of wild (river system) and captive (hatchery reared) population of common carp. A total of thirty samples (15 from hatchery and 15 from river Swat) were collected. All the specimens were examined in Laboratory of Parasitoloy, Zoology Department, University of Malakand. Findings indicated that wild population were greater in brain size and weight as compared to hatchery reared population. The fish samples collected from captive environment (hatchery) were showing more weight and length as compared to wild population of common carps. The mean value of total weight of hatchery fishes 345±48.68 and the mean value of brain weight of hatchery reared fishes 0.28±0.047. The mean value of wild fish's total body weight 195.16±52.58 and the mean value of brain weight of wild fishes are 0.45±0.14. Present research calls for the fact that fish in dependent environmental conditions possess brain larger in size as compared to its captive population, it is due to use and disuse of brain in their environmental requirements.

Mortality and long-term outcomes of palliative inotropes in ischemic and non-ischemic cardiomyopathy

Background

Palliative inotropes are frequently utilized for symptom management in patients with end stage heart failure who are unable to undergo durable advanced heart failure therapies. With the advent of improved medical management and early intervention, palliative inotropes may allow for improved patient outcomes than seen previously. In this study, we aim to investigate the survival and outcomes of palliative inotrope therapy and its impacts on ischemic versus non-ischemic cardiomyopathy.

Methods

We retrospectively analyzed 220 patients with American Heart Association Stage D heart failure who were discharged with palliative inotrope therapy after January 1, 2010. Patients who underwent mechanical circulatory support (MCS) or those who underwent heart transplant were excluded. Those with a history of coronary artery disease, myocardial infarction, history of percutaneous intervention, or coronary artery bypass grafting were assigned to ischemic cardiomyopathy (ICM), while patients without these findings were assigned to non-ischemic cardiomyopathy (NICM). Statistical analysis was completed using Chi-Square and Student's t-tests, wherein p<0.05 was considered statistically significant.

Results

Of the 220 patients, 87 had NICM as opposed to 133 with ICM. Mean age was found to be higher among patients with ICM (70 [62–79]) compared to NICM (65 [55–72], p-value <0.01). No significant difference was seen in total days on inotrope therapy (p=0.6). While more patients in both groups were placed on milrinone as opposed to dobutamine, there was no difference between patients with ischemic and NICM (p=0.66 and 0.51 respectively). Although a greater number of patients with NICM had been lost to follow up, admitted to hospice, or expired at 2 years (p<0.01), survival at 3 months, 1 year, and 2 years showed no difference between both groups. No difference was seen in number of hospitalizations or clinic visits in one year. Both groups had similar complication rates with intravenous-access related PICC line infections and new arrhythmias. (See Table).

Conclusion

Despite more frequent use of durable mechanical support devices, many patients who are deemed unsuitable for invasive measures are treated with palliative inotrope therapy. We have found that there is no significant difference in survival, complications, and outcomes of patients on palliative inotropes among ischemic and NICM. These findings show the versatility of palliative inotrope therapy in end stage heart failure. Further studies with larger populations need to be evaluated.

Funding Acknowledgement

Type of funding sources: None.

Cerebrovascular accidents in patients supported with veno-arterial extra-corporeal membrane oxygenation- is duration of support important?

Purpose of study

Veno-Arterial Extra-corporeal Membrane Oxygenation (VA-ECMO) is indicated for refractory cardiac and/or respiratory failure. Adverse events remain considerable despite best practices. We specifically aimed to understand risk factors associated with cerebrovascular accidents (CVA) in patients who underwent VA-ECMO support.

Methods

We retrospectively assessed all VA-ECMO patients from 2007 to 2019 at our institution. We identified those who experienced a CVA while supported by VA-ECMO. Patients with the primary event (CVA) were matched to controls (no CVA) based on age and sex. Comparisons were made between groups using McNemar's, Mantel-Haenszel, and Wilcoxon Signed-Rank tests where appropriate.

Results

Of the 278 VA-ECMO patients in the registry, 32 patients who experienced a CVA were identified; 24 (8.6%) ischemic and 8 (2.9%) hemorrhagic. Median age was 59.5 years (inter-quartile range: 49–65 years) and 75% of patients were males. Hypertension, diabetes, CAD and CHF were common co-morbidities (Table 1). Cardiogenic shock was the most common indication for VA-ECMO support in both cohorts, 75% in cases and 71.9% in controls. Cannulation strategies were identified as central or peripheral. There was a significant association of duration of VA-ECMO support with incidence of CVA, with a p-value of 0.03. Regression analysis showed a trend of increased risk of CVA by 4% for each additional day on VA-ECMO, however, this was not statistically significant (Odds ratio: 1.04; confidence interval 1.00–1.08). Most common outcome was death followed by decannulation to recovery and bridge to LVAD.

Conclusion

Ischemic and hemorrhagic CVAs are not uncommon during VA-ECMO support. Our case control study shows an association of duration of VA-ECMO support with incidence of CVA. This underscores the importance of timely assessment and weaning or bridging of VA-ECMO patients to their next management step.

Funding Acknowledgement

Type of funding sources: None.

664 Factors and Outcomes Associated with Delays in Carotid Endarterectomy in Symptomatic Patients

Introduction

Carotid artery disease (CAD) contributes to 20% of ischaemic stroke. Carotid endarterectomy (CEA) reduces stroke risk significantly if performed within 14 days of the index event in symptomatic patients. Studies report delayed CEA is common in practice, however underlying reasons are poorly understood. The aim is to assess factors associated with delayed CEA, and to compare outcomes between timely and delayed CEA.

Method

This retrospective cohort study included 24 symptomatic CAD patients planned for CEA between October 2018 and December 2019 in a tertiary vascular unit. Time from index event to CEA was measured in “timely” (≤14 days) and “delayed” (>14 days) cohorts and causes for delay were explored. Univariate logistic regression was performed to assess factors associated with delay. Surgical outcomes at 30-days and 1-year were compared between cohorts.

Results

Overall, 58.3% (n = 14/24) patients underwent delayed CEA. Median time from index event to CEA was 10.5 (IQR 7.5-12) and 22 (IQR 16-32) days in timely and delayed cohorts respectively (P < 0.0001). The main cause of delay was deterioration in patient condition (50%, n = 7/14). In 35.7% (n = 5/14) reasons were unclear. No statistically significant factors were associated with a delay. All surgical outcomes, including 30-day mortality (0%, n = 0/10 vs 7.1%, n = 1/14;P>0.9999) and all-stroke (0%, n = 0/10 vs 14.3%, n = 2/14;P=0.4928), were not statistically significant between timely and delayed cohorts respectively.

Conclusions

A substantial proportion of patients undergo delayed CEA, with inconclusive associated factors. Those undergoing a delayed CEA did not comparatively have an adverse outcome, but numbers in our study were limited. A larger scale study with increased power is required.

473 A Review of The Risk Stratification Models Used in The Management of Oncological Hepato-Pancreato-Biliary Surgical Patients

Introduction

Oncological scoring systems in surgery are used as evidence-based decision aids to best support management through assessing prognosis, effectiveness and recurrence. Currently, the use of scoring systems in the hepato-pancreato-biliary (HPB) subspecialty is limited as concerns over precision and applicability prevent widespread clinical implementation. The aim of the review is to discuss clinically useful oncological scoring systems for the surgical management of HPB patients.

Method

Primary articles of validated novel and established scoring systems were searched over a 25-year period using PubMed, Cochrane and Ovid Medline.

Results

This review discusses 9 clinically useful scoring systems in cancers of the liver (CLIP, BCLC, ALBI Grade, RETREAT, Fong et al.), pancreas (Genc et al., mGPS) and biliary tract (TMHSS, MEGNA). CLIP and BCLC are extensively validated prognostic tools, with BCLC clinically endorsed by guidelines. Conversely, patient and treatment stratification is limited in CLIP and BCLC respectively - ALBI works to improve patient stratification. RETREAT, Fong et al. and Genc et al. scores predict recurrence following surgery, however these scores require further validation in heterogenous patient groups. mGPS and MEGNA are simple prognostic scores, but also require further validation in varied patient cohorts. TMHSS is user-friendly, however is limited at discriminating treatment for the middle patient group.

Conclusion

A diverse range of HPB surgical scoring systems may facilitate evidenced-based treatment decisions and improve management. Future scoring systems need to be developed on heterogenous patient cohorts with improved stratification, with current trends towards implementing machine learning and genetics to improve outcome prediction.

Isolation and characterization of bacteria residing in the oral, gut, and fecal samples of different pheasant species

There is a paucity of research conducted on microbial prevalence in pheasants. The microbiota of captive birds has zoonotic significance and must be characterize. Present study is therefore planned to assess the microbiota from oral, fecal and gut content of captive avian species. It will be helpful in characterization of harmful microbes. Different samples taken from oral, gut and feces of ring-necked pheasants (Phasianus colchicus), green pheasants (Phasianus versicolor), golden pheasant (Chrysolophus pictus) and silver pheasant (Lophura nycthemera). Samples were collected, diluted, and inoculated onto different agar plates (MacConkey, SS agar, MSA and nutrient agar) for cultivation of bacterial species. Colonies of E.coli, Staphylococcus spp. Brachyspira spp. and Campylobacter spp were observed based on colony morphology. Colony forming unit showed E. coli as frequently found bacteria in fecal, oral and gut contents of all the above pheasants. The overall significance difference was found among bacterial species of golden pheasants, green pheasant, ring-necked pheasant, and silver pheasants. It was concluded that E.coli is predominant isolated from heathy pheasants followed by Campylobacter, Staphylococcus and Brachyspira.

A summary of the updated report on the incidence and epidemiological trends of keratinocyte cancers in the United Kingdom 2013-2018

Skin cancer is the commonest cancer in the UK. Skin cancer referrals via the two-week wait (urgent suspected cancer) pathway outnumber any other suspected malignancy.^{1, 2} The commonest skin cancers are keratinocyte cancers (KCs) which represents Basal Cell Carcinomas (BCC) and Cutaneous Squamous Cell Carcinomas (cSCC). Accurate KC incidence reporting is crucial for healthcare planning.

Physiological and biochemical changes induced by Qiangdi nano-863 biological assistant growth apparatus during rice seed priming under temperature stress

A huge amount of rice cultivation and consumption occur in Asia particularly in Pakistan and China. However, multiple abiotic stresses especially high and low-temperature proved to be a substantial threat for rice production ultimately risks for food security. To overcome various types of abiotic stress; seed priming is among the effective approaches to improve the rice seed germination and growth vigor. Therefore, the present study was planned to evaluate physiological and biochemical modifications in Chinese and Pakistani rice varieties by Qiangdi 863 biological assistant growth apparatus nano treated water (NTW), Osmopriming Calcium chloride (CaCl2), redox priming hydrogen peroxide (H2O2) and hormonal priming by Salicylic acid (SA) under temperature stress conditions. The experiment was performed with completely randomize design conditions. Five rice varieties, nomenclature as Zhongzoa 39, (Chinese rice variety) KSK 133, KS 282, Super basmati and PK 1121 aromatic (Pakistani rice variety) were sown under low temperature (LT) (17ºC), optimal temperature (OT) 27ºC and high temperature (HT) 37ºC conditions. The present study indicated that nanopriming were the most effective treatments increased Germination Energy Percentage (GEP) (96.1, 100, 100%), Speed of Germination (SG) (27.2, 35.45, 37.1), Final Germination Percentage (FGP) (98.2, 99.1, 99.4%), Seedling Dry Weight Biomass (DWB) (0.1, 0.137, 0.14g), Total Chlorophyll Content (0.502, 13.74, 15.21), antioxidant enzymes Superoxide Dismutase (SOD)(3145, 2559, 3345 µg-1FWh-1), Catalase (CAT) (300, 366, 3243 µg-1FWh-1) and decreased Malondialdehyde (MDA) (6.5, 12.2, 6.5 µmol g-1 FW) for Zhongzao 39 and KSK 133 rice varieties under low (LT+NTW), optimal temperature (OP+NTW) and high temperature (HT+NTW) stress., Therefore, nano-priming is recommended to cope with the high and low-temperature stress conditions along with improved productivity of rice.

Cross-genera amplification and identification of Colpodella sp. with Cryptosporidium primers in fecal samples of zoo felids from northeast China

The protozoans include many intracellular human pathogens. Accurate detection of these pathogens is necessary to treat the diseases. In clinical epidemiology, molecular identification of protozoan is considered a more reliable and rapid method for identification than microscopy. Among these protozoans, Cryptosporidium considered being one of the important water-borne zoonotic pathogens and a major cause of a diarrheal disease named cryptosporidiosis in humans, domestic animals, and wild animals. This study was aimed to identify Cryptosporidium in zoo felids (N= 56) belonging to different zoo of China, but accidentlly Colpodella was encountered in the zoo felids sample and phylogenetic data confirmed this unexpected amplification from fecal samples using two-step nested-PCR. Phylogenetic analysis revealed the fact about the specific primers used previously by many researchers and cross-genera amplification. We came to know that genetically sequenced amplicon gives more accurate identification of species. This study suggests more investigation on Colpodella which has been neglected previously but gains the attention of researchers after identified from humans and animals and has been known to correlate with neurological symptoms in patients.

Phylogeography of cliff racer (Platyceps rhodorachis Jan, 1865) from Punjab, Pakistan

The present study reports the existence of cliff racer, Platyceps rhodorachis from the plains of Punjab, Pakistan. A total of 10 specimens were captured during the field surveys from June to September, 2018 from different sites of Punjab. Platyceps rhodorachis was identify on the basis of morphology and confirmed through COI gene sequences. The obtained DNA sequences have shown reliable and exact species identification. Newly produced DNA sequences of Platyceps rhodorachis were submitted to GenBank and accession numbers were obtained (MK936174.1, MK941839.1 and MT790210.1). N-J tree based on COI sequences of Platyceps rhodorachis clearly separated as out-group with other members of family Colubridae based on p-distance. The intra-specific genetic variation ranges from 12% to 18%. The DNA sequences of Platyceps rhodorachis kashmirensis, Platyceps rhodorachis ladacensis, Platyceps ventromaculatus, Platyceps ventromaculatus bengalensis and Platyceps ventromaculatus indusai are not available at NCBI to validate their taxonomic positions. In our recommendations, a large scale molecular based identification of Pakistan's herpetofauna is required to report more new or subspecies from country.

Characterization of serum adiponectin and leptin in healthy perinatal dairy cows or cows with ketosis, and their effectson ketosis involved indices

We investigated changes in concentrations of ADP (adiponectin), LEP (leptin), BHBA (beta-hydroxybutyric acid), NEFA (non-esterified fatty acid), Glucose (Glu) and INS (insulin) in serum of healthy perinatal dairy cows and cows with ketosis. Twenty-one healthy cows and seventeen cows with ketosis from a herd of a total 60 Holstein cows (near dry period i.e. 56 days antepartum) were selected. Blood was collected through the tail vein every 7 days, from 56 day antepartum to 56 day postpartum. Serum ADP, LEP, BHBA, NEFA, Glu, and INS concentrations were determined, and ketosis was diagnosed through serum BHBA (≥1.2 mmol/L). We showed the concentration of serum adipokines and energy balancing indices were stable during antepar- tum period. However, ADP concentration increased while LEP decreased, and there were a significant increase in cows with ketosis compared to that of in healthy cows. Serum BHBA and NEFA concentrations increased significantly at first, and then gradually decreased in both healthy cows and cows with ketosis. However, cows with ketosis showed higher concentrations of BHBA and NEFA which restored later. The serum concentration of Glu in both healthy dairy cows and cows with ketosis showed a decreasing trend. INS concentration in healthy cows was decreased while it was increased in cows with ketosis. The results reflect the extent of hypo- glycemia and lipid mobilization postpartum, suggest IR exists in cows with ketosis while serum ADP and LEP might play roles in the development of ketosis.

434 LOOK OUT! VISUAL ASSESSMENT TOOL: UTILITY IN OLDER PERSON’S MENTAL HEALTH CARE SETTINGS

Introduction

Patients on old age psychiatry wards are at high risk of falls. It has been shown that poor visual acuity significantly increases the risk of recurrent falls in the elderly. The National Audit of Inpatient Falls (NAIF) Report 2015 found that vision was poorly assessed. The Look Out! Visual assessment has been developed for patients over 65 to receive visual screening on admission to reduce the risk of falls. To date, there has been no research into the applicability of the Look Out! test in mental health settings. Our aims are two-fold: (i) To investigate how often vision is assessed for inpatients on old age psychiatry wards and (ii) To identify the challenges of visual assessment in a mental health care setting.

Methodology

Data was collected at a mental health unit with two wards dedicated to old age psychiatry patients. Data was collected for patients admitted from May 2020 to July 2020 and analysing qualitative and quantitative data.

Results

From the 30 patients reviewed, 27% of patients had ophthalmic history, such as glaucoma or cataracts, 23% of patients had a fall during admission, yet only 43% of patients had a Look Out! vision assessment completed and documented. 54% of patients who had a Look Out! Assessment were found to have an abnormality; of those with an abnormality detected on Look Out!, 57% were new presentations of an eye abnormality. On questionnaires, we found it more challenging to complete assessments of patients that were agitated or with advanced dementia but assessments were fully completed if more time was dedicated.

Conclusions

These findings demonstrate that the Look Out! test is applicable in mental health settings, helping to identify those with visual impairments and raising the need to complete the screening tool in all patients admitted to inpatient mental health facilities.

The global landscape of availability, accessibility and affordability of essential diagnostics and therapeutics for the management of HER2-positive breast cancer: The ONCOLLEGE-001 survey

AIM OF THE STUDY

Barriers in access to essential care are key determinants of disparities in cancer survival. Breast cancer (BC) is the most common cancer and lead cause of mortality among women, 60 % occurring in low- and middle-income countries (LMs). A quarter of BC are characterized by an over-expression of the epidermal growth factor receptor 2 (HER2). Valuable strategies to diagnose and manage patients with HER2-positive BC have been determined and some considered essential health interventions. ONCOLLEGE-001 is a global survey of availability, accessibility, and affordability of essential HER2 diagnostics and therapeutics.

METHOD

A self-administered questionnaire was shared electronically to oncologists, identified from oncology networks. Data were analyzed using descriptive statistics, per income areas and geographic regions.

RESULTS

We received 191 responses (84 % response rate). The majority of the responders were from LMs (n = 153) and were physician providers. Immunohistochemistry was the most common HER2 diagnostics available (n = 185). A third of the responders from low/lower-middle and a half of upper-middle income countries had HER2 testing only in the private sector. Trastuzumab was not available for 8 %: when available, 15%-21% reported accessibility only as out-of-pocket expenditure; when not reimbursed, only 10 % of the providers could significantly offer this intervention. Availability of trastuzumab biosimilars was reported in more than a half of the responders (n = 107).

CONCLUSION

Stark disparities are reported, with high out-of-pocket expenses for HER2 testing and significant financial barriers to access trastuzumab treatments. Policy solutions are urgently warranted for the selection, prioritization, and reimbursement of essential health interventions, to result in improved population health. POLICY SUMMARY STATEMENT: the inclusion of essential services for cancer management should be assured and financed in the benefit packages of healthcare to all. Prioritizing high-value health interventions, including medicines and medical devices, is critical to deliver impactful programs on population health.

Evolution of AITR family genes in cotton and their functions in abiotic stress tolerance

Abiotic stresses are major environmental factors inhibiting plant growth and development. AITRs (ABA-induced transcription repressors) are a novel family of transcription factors regulating ABA (abscisic acid) signalling and plant responses to abiotic stresses in Arabidopsis. However, the composition and evolution history of AITRs and their roles in the cotton genus are largely unknown. A total of 12 putative AITRs genes were identified in cultivated tetraploid cotton, Gossypium hirsutum. Phylogenetic analysis of GhAITRs in these tetraploid cottons and their closely related species implicate ancient genome-wide duplication occurring after speciation of Gossypium, and Theobroma could generate duplicates of GhAITRs. Duplicated GhAITRs were stably inherited following diploid speciation and further allotetraploidy in Gossypium. Homologous GhAITRs shared common expression patterns in response to ABA, drought and salinity treatments, and drought tolerance induced in transgenic Arabidopsis plants expressing GhAITR-A1. Together, our findings reveal that duplicates in the GhAITRs gene family were achieved by whole genome duplication rather than three individual duplication events, and that GhAITRs function as transcription repressors and are involved in the regulation of plant responses to ABA and drought stress. These results provide insights towards the improvement of abiotic stress tolerance in cotton using GhAITRs.

Optimal NH4 + /NO3 - ratios enhance the shade tolerance of soybean seedlings under low light conditions

In the maize-soybean intercropping system, shade is the major chronic restraint that affects normal growth of soybean. Different spatial patterns of this system affect the microclimate of soybean through shading from maize plants. However, the negative impacts of shading stress can be mitigated by providing optimal ratios of different fertilizers. Therefore, to test this hypothesis, soybean plants were grown under different light conditions (normal light or shade) to evaluate the response to varying NH4 + /NO3 - ratios. Seeds of soybean (Glycine max L. cv. Nan-99-6) were grown in nutrient solution with a total concentration of 5 mM N using different NH4 + /NO3 - ratios (T0  = 0:0, T1  = 0:100, T2  = 25:75, T3  = 50:50 and T4  = 75:25) for 40 days in a greenhouse at PPFD 320.95 μmol m-2  s-1 (low light) or 967.53 μmol m-2  s-1 (normal light). Under low light, growth and photosynthesis of soybean seedlings significantly decreased as compared to normal light conditions. However, the optimal ratios of NH4 + / NO3 - improved growth and photosynthesis of soybean seedlings under both light conditions. Our results indicated that soybean seedlings supplied with optimal NH4 + /NO3 - ratios (25:75 and 50:50) have maximum biomass yield, chlorophyll pigments, leaf gas exchange, photochemical activity and root growth as compared to low and high NH4 + /NO3 - ratios (T1 and T4 ). High ratios of NH4 + /NO3 - (T4 ) resulted in reduced plant growth due to nutrient accumulation in plant tissues; therefore, we suggest that optimal ratios of NH4 + /NO3 - (T2 and T3 ) can enhance the shade tolerance of soybean seedlings.

The effect of the COVID-19 pandemic on time to angiography and outcomes in patients presenting with non-ST elevation myocardial infarction

Funding Acknowledgements

Type of funding sources: None.

Background

Covid-19 pandemic has had a profound impact on healthcare service delivery. Acute cardiovascular care however remains a priority despite the pandemic. Patients presenting with non-ST elevation MI (NSTEMI) have been poorly characterised during the pandemic.

Methods

We conducted a retrospective study of patients diagnosed with NSTEMI during the peak of the pandemic between April-May 2020 at our tertiary centre in the UK. Data was collected from electronic patient clinical records including time from admission to angiography, length of stay, mortality, prescription of secondary prevention pharmacotherapy and referral to cardiac rehabilitation. We compared this data to the same time period in 2019.

Results

As can be seen from Table 1, in 2020, the mean age, median time to angiography and length of stay were all significantly lower than the control period of 2019. Prescription of secondary prevention medication (Aspirin, P2Y12 inhibitor, Beta-blocker, Statin and ACEi/ARB) and referral to cardiac rehabilitation also improved in 2020, however neither was statistically significant.

During the 2020 period, 1 patient died due to late presentation NSTEMI and multi-organ failure. There were 3 deaths in 2019: complications following coronary bypass surgery, upper GI bleed and a subarachnoid haemorrhage.

Conclusion

Our results show that the mean age of the patients presenting with NSTEMI during the peak of Covid-19 pandemic was younger suggesting that elderly patients failed to present. Compared to 2019, there was significant improvement in patient treatment times with a significantly shorter stay in hospital, probably as a result of the reduction in elective activity allowing un-restrained access to the catheter labs.  We also saw improvement in prescription for secondary prevention and referral to cardiac rehabilitation services during this time suggesting that there may have been improved focus on these aspects of care again.

Swept Langmuir probe investigation of a time varying DC discharge

The paper reports on the development and application of a swept Langmuir probe to characterize plasma between two disc-like electrodes. A battery was added to a probe circuit to offset against the cathode fall voltage, and to make the sweep voltage effective at the probe tip. This arrangement allowed the collection of the electron and ion parts of the probe current and the subsequent construction of time-resolved current–voltage IP(V) characteristics with a time resolution of about one millisecond. The probe collected electron current in the lower voltage region of the discharge waveform where it surmounted the cathode fall voltage, whereas the ion current was collected continuously due to an accelerating field for the ions. The results highlighted how the cathode fall voltage limits the collection of the electron and ion parts of the probe current and how to handle the problem with a series battery in the probe circuit. In addition to the swept single-probe, a triple-probe was used simultaneously to compare and validate the results.