Lesion Eccentricity Plays a Key Role in Determining the Pressure Gradient of Serial Stenotic Lesions: Results from a Computational Hemodynamics Study

PURPOSE

In arterial disease, the presence of two or more serial stenotic lesions is common. For mild lesions, it is difficult to predict whether their combined effect is hemodynamically significant. This study assessed the hemodynamic significance of idealized serial stenotic lesions by simulating their hemodynamic interaction in a computational flow model.

MATERIALS AND METHODS

Flow was simulated with SimVascular software in 34 serial lesions, using moderate (15 mL/s) and high (30 mL/s) flow rates. Combinations of one concentric and two eccentric lesions, all 50% area reduction, were designed with variations in interstenotic distance and in relative direction of eccentricity. Fluid and fluid-structure simulations were performed to quantify the combined pressure gradient.

RESULTS

At a moderate flow rate, the combined pressure gradient of two lesions ranged from 3.8 to 7.7 mmHg, which increased to a range of 12.5-24.3 mmHg for a high flow rate. Eccentricity caused an up to two-fold increase in pressure gradient relative to concentric lesions. At a high flow rate, the combined pressure gradient for serial eccentric lesions often exceeded the sum of the individual lesions. The relative direction of eccentricity altered the pressure gradient by 15-25%. The impact of flow pulsatility and wall deformability was minor.

CONCLUSION

This flow simulation study revealed that lesion eccentricity is an adverse factor in the hemodynamic significance of isolated stenotic lesions and in serial stenotic lesions. Two 50% lesions that are individually non-significant can combine more often than thought to hemodynamic significance in hyperemic conditions.

Obstetric anaesthesiology: manpower and service provision issues in India

Obstetric anaesthesiologists play a pivotal role as peripartum physicians steering the team of obstetric healthcare providers towards a continuum of medical education, enhanced training and safer patient care. However, in resource-limited countries, deficiency of human resources and hence services available poses challenges to those attempting to reduce maternal mortality rates. Measures to fill the gap include creating a cadre of uniformly well-trained and certified non-physician anaesthesia providers (NPAPs) supervised by a physician obstetric anaesthesiologist and well-equipped rural and urban health care facilities. The Association of Obstetric Anaesthesiologists of India needs to upscale their outreach programs with regular knowledge updates and practical skill training to the NPAPs, medical graduates and postgraduate doctors in these regions. A combination of strong local administrative will, legislation for the provision of essential supplies and a global collaborative effort using checklists and protocols may help to stem gaps in the provision of safe maternal care.

Transarterial radioembolization: a systematic review on gaining control over the parameters that influence microsphere distribution

[Purpose] Transarterial radioembolization (TARE) is an established treatment modality for patients with unresectable liver cancer. However, a better understanding of treatment parameters that influence microsphere distribution could further improve the therapy. This systematic review examines and summarizes the available evidence on intraprocedural parameters that influence the microsphere distribution during TARE as investigated by in vivo, ex vivo, in vitro and in silico studies. [Methods] A standardized search was performed in Medline, Embase and Web of Science to identify all published articles investigating microsphere distribution or dynamics during TARE. Studies presenting original research on parameters influencing the microsphere distribution during TARE were included. [Results] A total of 42 studies reporting a total of 11 different parameters were included for narrative analysis. The investigated studies suggest that flow distribution is not a perfect predictor of microsphere distribution. Increasing the injection velocity may help increase the similarity between flow and microsphere distributions. Furthermore, the microsphere distributions are very sensitive to the radial and axial catheter position. [Conclusion] The most promising parameters for future research which can be controlled in the clinic appear to be microsphere injection velocity as well as the axial catheter position. Up to now, many of the included studies do not take clinical feasibility into account, limiting the translation of results to clinical settings. Future research should therefore focus on the applicability of in vivo, in vitro, or in silico research to patient specific scenarios to improve the efficacy of radioembolization as treatment for liver cancer.

VENUM (Vascular Education iN Undergraduate Medicine): a multicentre evaluation of undergraduate vascular education in the UK

INTRODUCTION

Vascular surgery is a recognised surgical subspecialty covering an array of circulatory conditions predominately affecting geriatric and diabetic patients. As such, a wide breadth of clinicians will see patients with vascular pathologies, but it is unclear how detailed their knowledge base is. Key to this is the education of medical students, which has been poorly documented during undergraduate training in the UK. VENUM aimed to establish students' perceptions of vascular surgery and their confidence in performing vascular objective structured clinical examination (OCSE) skills.

METHODS

During the academic year of 2022/2023, final-year medical students were invited to complete a JISC survey (collaborative authorship). Seventy-seven research leads were recruited to disseminate the survey. Quantitative and thematic analysis was used to assess the data.

RESULTS

In total, 240 final-year medical students completed the survey (54% female; 26 medical schools represented). Forty-five per cent of students reported never having had a vascular placement, 24% had never completed a vascular-focused clinical examination and 26% reported low confidence in performing ankle brachial pressure index measurement. An assessment of peripheral arterial disease morbidity was answered correctly in 17% of respondents compared with 92% for angina (chi-square test p<0.001). Students perceived the specialty to be non-inclusive and that early exposure to vascular surgery was required for better engagement with the specialty.

CONCLUSION

Students have experienced little exposure to vascular surgery. This may affect future recruitment to vascular surgery and overall knowledge of vascular conditions in UK-trained doctors, which may affect long-term patient management.

Correlation of Dose Volume Parameters with Dysphagia and Pharyngeal Constrictor Muscle Thickness in Dysphagia Optimized IMRT

PURPOSE/OBJECTIVE(S)

Reduced radiation dose to the pharyngeal constrictor muscles (PCM) using dysphagia optimized intensity-modulated RT (DO-IMRT) is associated with improved swallowing outcomes in oropharyngeal cancers (OPCs). Purpose was to evaluate the relationship between dose of radiation delivered and acute dysphagia in patients with OPC treated with IMRT, after delineation of PCM.

MATERIALS/METHODS

Twenty-five patients with newly diagnosed OPC who underwent definitive IMRT with concurrent cisplatin were included in the study. PCM mean dose < 50 Gy was used as the dose constraint. Target volume was divided into high, intermediate and low risk areas receiving doses in the range of 60-66 Gy, 54-58 Gy, 51-56 Gy in 30-33 fractions over 6-6.5 weeks, respectively. PCM dose-volume parameters were collected and logistic regression was used to analyze these data relative to percent weight loss during RT and duration of feeding tube use. Thickness of constrictor muscle in pre-treatment and 3 months post-therapy CT scan were assessed. Weekly assessment of dysphagia was based on RTOG toxicity gradings. Aim of the study was to evaluate the correlation between dysphagia grades with dose-volume parameters and PCM thickness.

RESULTS

Median age was 55.0 years (mean 54.3) with 24 males and stage II:III-16:9 patients. Dmean to PCM was 49.86 Gy (range 48.22 -57.63) with median Dmax of 70.24 Gy. For patients with dysphagia (grade ≥1), V50 ranged from 48.2-57.23%, while in those with no dysphagia, it ranged from 47.92-52.18 % (Mean 51.36%). Nine patients needed feeding tube after RT end. Median feeding tube duration was 64 days. The correlation between Dmean ≥ 50 Gy and dysphagia at 1st, 2nd, 3rd and 6th month was found statistically significant (p < 0.01). Table 1 shows the Pearson correlation and P-value of the dosimetric parameters with dysphagia. The correlation of V50 was found statistically significant with grade of dysphagia at 3rd and 6th month post-treatment (p<0.001). The mean thickness range and median thickness of constrictors before and 3 months after treatment were 1.8-3.2 mm, 2.4 mm, and 2.8-6.2 mm,4.1 mm, respectively. The increase in thickness of constrictor muscle correlated significantly (p<0.05) with dysphagia grades and also with V50, V60 and Dmean (p<0.001) but no statistical significance was seen with Dmax (p = 0.232). With a median follow-up of 18 months (range 7-24), 1-year actuarial local control was 92%.

CONCLUSION

DO-IMRT may prove beneficial in the OPC by preventing dysphagia and aspiration post therapy and hence improving the quality of life of patients. Dmean ≥ 50Gy, V50 > 51.4% and V60 > 35.5% are the parameters correlating significantly with dysphagia (p<0.001) and change in mean thickness of PCM (p<0.001).

RETINITIS PIGMENTOSA ASSOCIATED WITH THE EYS C2139Y VARIANT : An Important Cause of Blindness in East Asian Populations

PURPOSE

The study aimed to describe the phenotypic features of retinitis pigmentosa (RP) associated with the previously described EYS C2139Y variant in Singaporeans and establish the importance of this variant as a prevalent cause of RP among East Asians.

METHODS

A clinical phenotyping and exome-sequencing study was conducted on consecutive patients with nonsyndromic RP. Epidemiological analysis was performed using Singaporean and global population-based genetic data.

RESULTS

A study of 150 consecutive unrelated individuals with nonsyndromic RP found that 87 (58%) of cases had plausible genotypes. A previously described missense variant in the EYS gene, 6416G>A (C2139Y), occurred heterozygously or homozygously in 17 of 150 families (11.3%), all with autosomal recessive RP. Symptom onset in EYS C2139Y-related RP ranged from 6 to 45 years, with visual acuity ranging from 20/20 at 21 years to no light perception by 48 years. C2139Y-related RP had typical findings, including sectoral RP in cases with EYS E2703X in trans . The median age at presentation was 45 years and visual fields declined to less than 20° (Goldmann V4e isopter) by age 65 years. Intereye correlation for visual acuity, fields, and ellipsoid band width was high (r 2 = 0.77-0.95). Carrier prevalence was 0.66% (allele frequency of 0.33%) in Singaporean Chinese and 0.34% in East Asians, suggesting a global disease burden exceeding 10,000 individuals.

CONCLUSION

The EYS C2139Y variant is common in Singaporean RP patients and other ethnic Chinese populations. Targeted molecular therapy for this single variant could potentially treat a significant proportion of RP cases worldwide.

Lipid remodeling in megakaryocyte differentiation and platelet biogenesis

Lipid remodeling, from fatty acid transport and de novo lipid synthesis, is necessary for megakaryocyte differentiation and platelet production. Dietary saturated fatty acids, impaired fatty acid transport and/or dysfunction in lipid biogenesis can contribute to low platelet counts.

Natural Killer Cell Activation by Ubiquitin-specific Protease 6 Mediates Tumor Suppression in Ewing Sarcoma

Ewing sarcoma is a rare and deadly pediatric bone cancer for which survival rates and treatment options have stagnated for decades. Ewing sarcoma has not benefited from immunotherapy due to poor understanding of how its immune landscape is regulated. We recently reported that ubiquitin-specific protease 6 (USP6) functions as a tumor suppressor in Ewing sarcoma, and identified it as the first cell-intrinsic factor to modulate the Ewing sarcoma immune tumor microenvironment (TME). USP6 induces intratumoral infiltration and activation of multiple innate immune lineages in xenografted nude mice. Here we report that natural killer (NK) cells are essential for its tumor-inhibitory functions, as NK cell depletion reverses USP6-mediated suppression of Ewing sarcoma xenograft growth. USP6 expression in Ewing sarcoma cells directly stimulates NK cell activation and degranulation in vitro, and functions by increasing surface levels of multiple NK cell-activating ligands. USP6 also induces surface upregulation of the receptor for the apoptosis-inducing ligand tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), providing an additional route for enhanced sensitivity to NK cell killing. Furthermore, USP6-expressing Ewing sarcoma and NK cells participate in a paracrine immunostimulatory feedforward loop, wherein IFNγ secreted by activated NK cells feeds back on USP6/Ewing sarcoma cells to induce synergistic expression of chemokines CXCL9 and CXCL10. Remarkably, expression of USP6 in subcutaneous Ewing sarcoma xenografts induces systemic activation and maturation of NK cells, and induces an abscopal response in which growth of distal tumors is inhibited, coincident with increased infiltration and activation of NK cells. This work reveals how USP6 reprograms the Ewing sarcoma TME to enhance antitumor immunity, and may be exploited for future therapeutic benefit.

Significance

This study provides novel insights into the immunomodulatory functions of USP6, the only cancer cell-intrinsic factor demonstrated to regulate the immune TME in Ewing sarcoma. We demonstrate that USP6-mediated suppression of Ewing sarcoma tumorigenesis is dependent on NK cells. USP6 directly activates NK cell cytolytic function, inducing both intratumoral and systemic activation of NK cells in an Ewing sarcoma xenograft model.

Characterizing the genotypic spectrum of retinitis pigmentosa in East Asian populations: a systematic review

BACKGROUND

Ongoing trials for retinitis pigmentosa (RP) are genotype-specific, with most trials conducted on European cohorts. Due to genetic differences across diverse ancestries and populations, these therapies may not be efficacious in East Asians.

MATERIALS AND METHODS

A literature search was conducted from 1966 to September 2022 for cohort studies on East Asian populations reporting on non-syndromic RP genotypes and variants. Population-weighted prevalence was used to determine the genotypes and individual variants across the entire cohort. The carrier prevalence of common variants was compared against those in Europe.

RESULTS

A total of 12 articles describing 2,932 clinically diagnosed East Asian RP probands were included. We identified 876 variants across 54 genes. The most common genotypes included USH2A, EYS, RPGR, ABCA4, PRPF31, RHO, RP1, RP2, PDE6B and SNRNP200, with USH2A as the most common (17.1%). Overall, 60.5% of probands with clinically relevant variants were found to have one of the genotypes above, with 543/876 (62.0%) of the variants occurring in these genes. The most frequently reported variant was USH2A missense variant c.2802T>G/p.C934W (4.9%). Carrier prevalence of these variants was significantly different (p < 0.0001) than in Europe.

CONCLUSIONS

USH2A was the most commonly affected RP gene in this East Asian cohort, although sub-population analysis revealed distinct genotype prevalence patterns. While the genotypes are similar between East Asia and European cohorts, variants are specific to East Asia. The identification of several prevalent variants in USH2A and EYS provides an opportunity for the development of therapeutics that are relevant for East Asia patients.

Profile of Childhood Glaucoma Attending a Tertiary Eye Care Center in Northern India

Purpose

To ascertain the prevalence and clinical features of the various types of childhood glaucoma at a tertiary eye care hospital in Northern India.

Materials and methods

Retrospective chart review of all children less than 16 years of age with childhood glaucoma who presented from 1st April 2014 to 31st March 2019, who was diagnosed to have any subtype of childhood glaucoma as per Childhood Glaucoma Research Network (CGRN) classification and advised appropriate management.

Results

Out of 405 children with childhood glaucoma, 36% had primary glaucoma, whereas the rest had secondary glaucoma. Primary congenital glaucoma (PCG) was the most common form of primary glaucoma. Glaucoma associated with acquired conditions was the most common cause of secondary glaucoma. Primary glaucoma was mostly bilateral in contrast to secondary glaucoma. The most common age of presentation with primary glaucoma was <1 year of age, and in children with secondary glaucoma was 11-16 years. On presentation, 80% of eyes had intraocular pressure (IOP) of >20 mm Hg and 70% had cupping of >0.7. Eyes with PCG were primarily managed surgically.

Conclusion

In our cohort, PCG was the most common primary childhood glaucoma. Traumatic glaucoma was the most common secondary glaucoma. Since childhood glaucoma is an important cause of visual morbidity in children, its timely diagnosis and prompt management are essential to prevent irreversible visual loss.

Clinical significance

Understanding the disease pattern, their presenting features, and the proportion of different types of childhood glaucoma can help in planning appropriate eye care services, create awareness and better allocate resources to plan appropriate management strategies. Screening programs and counseling of parents should also be strengthened.

How to cite this article

Dubey S, Jain K, Pegu J, et al. Profile of Childhood Glaucoma Attending a Tertiary Eye Care Center in Northern India. J Curr Glaucoma Pract 2023;17(2):68-74.

Does Structured Patient Education Reduce the Peri-Operative Anxiety and Depression Levels in Elective Chest Surgery Patients? A Double-Blinded Randomized Trial of 300 Patients

Psychological distress associated with surgery is an emerging issue. The study was conducted to assess the impact of structured patient education viz-a-viz routine patient education on anxiety and depression levels in patients undergoing elective chest surgery. It is a prospective, double-blind randomized study, conducted from February 2019 to February 2020 at a tertiary care center in India, on patients who underwent elective chest surgeries. A total of 300 patients were randomized using a computer-generated randomization sequence, into 2 equal groups (150 subjects each). Study group included patients who underwent structured patient education (Group A), whereas control group included patients who underwent routine patient education (Group B). The 2 groups were compared for anxiety and depression levels at admission as well as discharge using Hospital Anxiety and Depression Scale. Also, at the time of discharge, the groups were compared for the effectiveness of patient education using a validated Questionnaire B. In comparison to routine education, patients receiving structured education showed significantly lesser scores for anxiety and depression at discharge (P < .001). Also, structured patient education proved to be effective in comparison to the routine education in educating the patients in all parameters as determined by the Questionnaire B (P < .05). It can be concluded that structured educational intervention is strongly recommended in patients undergoing chest surgery which can help alleviate perioperative anxiety and depression. Such intervention helps patient get an understanding of the surgical procedure and assist them in facing the condition in a better way.

Platelet-derived TLT-1 promotes tumor progression by suppressing CD8+ T cells

Current understanding of tumor immunosuppressive mechanisms forms the basis for modern day immunotherapies. Immunoregulatory role of platelets in cancer remains largely elusive. Platelets from non-small cell lung cancer (NSCLC) patients revealed a distinct activation phenotype. TREM-like transcript 1 (TLT-1), a platelet protein, was increased along with enhanced extracellular release from NSCLC platelets. The increased platelet TLT-1 was also evident in humanized mice with patient-derived tumors. In immunocompetent mice with syngeneic tumors, TLT-1 binding to T cells, in vivo, led to suppression of CD8 T cells, promoting tumor growth. We identified direct interaction between TLT-1 and CD3ε on T cells, implicating the NF-κB pathway in CD8 T cell suppression. Anti-TLT-1 antibody rescued patients' T cells from platelet-induced suppression ex vivo and reduced tumors in mice in vivo. Clinically, higher TLT-1 correlated with reduced survival of NSCLC patients. Our findings thus identify TLT-1 as a platelet-derived immunosuppressor that suppresses CD8 T cells and demonstrate its therapeutic and prognostic significance in cancer.

Analysis of clinically relevant variants from ancestrally diverse Asian genomes

Asian populations are under-represented in human genomics research. Here, we characterize clinically significant genetic variation in 9051 genomes representing East Asian, South Asian, and severely under-represented Austronesian-speaking Southeast Asian ancestries. We observe disparate genetic risk burden attributable to ancestry-specific recurrent variants and identify individuals with variants specific to ancestries discordant to their self-reported ethnicity, mostly due to cryptic admixture. About 27% of severe recessive disorder genes with appreciable carrier frequencies in Asians are missed by carrier screening panels, and we estimate 0.5% Asian couples at-risk of having an affected child. Prevalence of medically-actionable variant carriers is 3.4% and a further 1.6% harbour variants with potential for pathogenic classification upon additional clinical/experimental evidence. We profile 23 pharmacogenes with high-confidence gene-drug associations and find 22.4% of Asians at-risk of Centers for Disease Control and Prevention Tier 1 genetic conditions concurrently harbour pharmacogenetic variants with actionable phenotypes, highlighting the benefits of pre-emptive pharmacogenomics. Our findings illuminate the diversity in genetic disease epidemiology and opportunities for precision medicine for a large, diverse Asian population.

Studying plaque characteristics in extracranial carotid artery disease using CT angiography - Risk predictors beyond luminal stenosis

OBJECTIVES

Carotid atherosclerosis accounts for around 20 % of ischemic strokes. Literature on CT angiography [CTA] to study plaque morphology is limited. We studied plaque characteristics of extracranial carotid arteries using CTA to ascertain the high risk features beyond luminal stenosis.

MATERIALS AND METHODS

Retrospective study design, where patients with carotid territory ischemia who underwent CTA from January 2011 till December 2015 were recruited from medical records. CT images were reviewed for plaque characteristics like attenuation, ulceration, plaque thickness and presence of intraluminal thrombus [ILT] along with percentage stenosis.

RESULTS

114 patients with 201 carotids [102 symptomatic and 99 asymptomatic] were reviewed. Mixed density plaques [p = 0.05], ulceration [p = 0.001], ILT [p = 0.004] and higher soft plaque thickness [p < 0.001] were significantly associated with symptomatic carotids whereas calcified plaques were seen in asymptomatic carotids [p = 0.005]. Plaque characteristics were comparable in symptomatic patients with moderate[50-69 %] and severe[70-99 %] stenosis. Multivariate analysis showed that increased soft plaque thickness remained significantly associated with symptomatic carotid. A cut-off value for soft plaque thickness of 2.75 mm could predict symptomatic carotid disease with a sensitivity of 85.2 % and specificity of 68.0 % [Youden's index]. An increase in soft plaque thickness of 4.0 mm significantly predicts change from asymptomatic to symptomatic carotid [p < 0.05].

CONCLUSIONS

Of the studied CTA plaque characteristics, soft plaque thickness is an independent predictor of symptomatic disease irrespective of the percentage stenosis. Soft plaque thickness over 2.75 mm and smallest detectable change[4 mm] are new measures to help ascertain the risk of ischemic events in carotid atherosclerotic disease.

Unfolded Protein Response Differentially Modulates the Platelet Phenotype

BACKGROUND

Unfolded protein response (UPR) is a multifaceted signaling cascade that alleviates protein misfolding. Although well studied in nucleated cells, UPR in absence of transcriptional regulation has not been described. Intricately associated with cardiovascular diseases, platelets, despite being anucleate, respond rapidly to stressors in blood. We investigate the UPR in anucleate platelets and explore its role, if any, on platelet physiology and function.

METHODS

Human and mouse platelets were studied using a combination of ex vivo and in vivo experiments. Platelet lineage-specific knockout mice were generated independently for each of the 3 UPR pathways, PERK (protein kinase RNA [PKR]-like endoplasmic reticulum kinase), XBP1 (X-binding protein), and ATF6 (activating transcription factor 6). Diabetes patients were prospectively recruited, and platelets were evaluated for activation of UPR under chronic pathophysiological disease conditions.

RESULTS

Tunicamycin induced the IRE1α (inositol-requiring enzyme-1alpha)-XBP1 pathway in human and mouse platelets, while oxidative stress predominantly activated the PERK pathway. PERK deletion significantly increased platelet aggregation and apoptosis and phosphorylation of PLCγ2, PLCβ3, and p38 MAPK. Deficiency of XBP1 increased platelet aggregation, with higher PLCβ3 and PKCδ activation. ATF6 deletion mediated a relatively modest effect on platelet phenotype with increased PKA (protein kinase A). Platelets from diabetes patients exhibited a positive correlation between disease severity, platelet activation, and protein aggregation, with only IRE1α-XBP1 activation. Moreover, IRE1α inhibition increased platelet aggregation, while clinically approved chemical chaperone, sodium 4-phenylbutyrate reduced the platelet hyperactivation.

CONCLUSIONS

We show for the first time, that UPR activation occurs in platelets and can be independent of genomic regulation, with selective induction being specific to the source and severity of stress. Each UPR pathway plays a key role and can differentially modulate the platelet activation pathways and phenotype. Targeting the specific arms of UPR may provide a new antiplatelet strategy to mitigate thrombotic risk in diabetes and other cardiovascular diseases.

O-232 Art of fibroid removal in patients with infertility

Aim of myomectomy in infertile patient is to preserve and improve fertility, minimising excessive bleeding and pain. Relation ship of myoma and fertility remains debatable moreover removal of all myomas may not be helpful in improving fertility outcome thus it becomes important to decide which fibroid should be removed and which one shouldn’t be touched. Principle of minimal damage and complication should be kept in mind. Mapping of fibroid is an important step in planning the route of operation.Number and site of myoma decides the approach. A preoperative  meticulous TVS examination supplemented by TAS specially in large and multiple fibroids is extremely helpful in decision making. it is also important to preoperative differentiation of adenomyosis and fibroid to avoid a surprise element and excessive bleeding during removal. Use of colour flow may be helpful in differentiating. Use of 3-D is important specially in borderline sub mucous myoma. Extent of myoma in to uterine cavity is very important to decide the route of operation. various classifications have attempted to simplify the decision making but combining usg and hysteroscopy is the best way to decide. it is also important to diagnose a large intramural myoma touching the junctional zone. Instilling methylene blue before operation to outline the cavity during surgery in case of accidental entry is a good practice. using intraoperative ultrasound while tackling a large intracavitary fibroid having more than 75% extent in intra myometrial region may be helpful in complete removal.

The placement of the optical and secondary ports determines the degree of ergonomic surgery performance, time and difficulty of myoma enucleation, and the ease of suturing. reducing the bleeding during enucleation, dissection in the right plane, minimal use of cautery and proper suturing and closure avoiding any haematoma formation are key points for a successful myomectomy. Use of diluted vasopressin is very effective in making the surgery blood less. So also the use of bipolar in coagulating the large blood vessels. Using bipolar diathermy, a dissecting grasper, and a suction cannula, meticulous exploration of the dissection field can more efficiently detect and coagulate any actively bleeding vessels. Slow rotation of the bevelled morcellator and good control of the bag could reduce de novo myoma and endometriosis. The surgery outcome and the risk of intraoperative complications are highly dependent on trocar placement, finding of the correct cleavage plane, haemostasis, and suturing technique. Flap technique is an innovative approach for removing small fibroid near junctional zone. Good surgery with respect to minimal destruction and handling of the healthy tissue, avoiding unnecessary organ manipulation, controlled bleeding, minimal coagulation, and reasonable operating time remain the best ways to diminish the risk of adhesion formation.It is very important to preserve the cavity, minimal adhesion formation and perfect suturing avoiding dead spaces and haematoma formation for a successful out come in infertile patient.

Abstract 3147: Natural killer cells mediate tumor-inhibitory functions of USP6 in Ewing sarcoma

INTRODUCTION: Understanding how Natural Killer (NK) cell activity is regulated by cancer cells is critical for developing NK-cell based immunotherapies. Our studies show that the deubiquitinating enzyme ubiquitin-specific protease-6 (USP6) can induce an immune-stimulatory hot tumor microenvironment in Ewing sarcoma (ES), the 2nd most common pediatric bone cancer. High USP6 expression in ES is associated with significantly improved overall and progression-free survival. We found that USP6 expression in ES cells inhibits xenograft growth in nude mice, but not NSG mice, implicating a role for the innate immune system, particularly cytotoxic NK cells. Notably, USP6 expression enhanced intra-tumoral abundance, activation, and proliferative capacity of NK cells. In vitro cytotoxicity assays confirm that USP6 can directly augment the ability of ES cells to activate NK cells. Based on these observations, we hypothesize that NK cells are essential for USP6-mediated tumor suppression and seek to determine the mechanism by which their cytolytic function is activated by USP6.

METHOD: We used ES cell lines A673 and RD-ES expressing USP6 in a doxycycline (dox)-inducible manner, the immortalized human NK cell line NK-92, and primary human and mouse NK cells. Athymic nude or RAG2-/- mice were xenografted subcutaneously with ES cell lines and fed dox-infused water to induce USP6. Immune cell abundance and activation were monitored both in tumors and peripheral blood by flow cytometry. For in vivo depletion of NK cells, 300ug of anti-NK1.1 (PK136) ab was injected i.p. into RAG2-/- mice one day prior to ES xenografting, then once weekly thereafter.

RESULTS: USP6 induces in ES cells the surface expression of multiple NK activating ligands, as well as receptors for the apoptotic factor TRAIL (DR5) and Type I/II interferons (IFNAR1 and IFNGR1), both in vitro and in vivo. This leads to enhanced NK activation and renders ES cells hypersensitive to NK-mediated cytotoxicity. IFNy released by activated NK cells feeds back on the USP6-expressing ES cells, inducing synergistic expression of multiple IFNy-inducible genes, including chemokines CXCL9/10 (chemoattractants for NK cells) and ICAM-1 (essential for immunological synapse formation between NK cells and their targets). A potent feed forward loop for NK activation/ES cell killing is thus generated. Concordantly, in RAG2-/- mice, USP6 induces increased intratumoral infiltration and activation of NK cells, and also, strikingly, systemic activation of NK cells. Depletion of NK cells using anti-NK1.1(PK136) completely abrogates USP6-mediated inhibition of ES xenograft growth.

CONCLUSION: NK cells are essential for mediating the tumor inhibitory functions of USP6 in ES. We posit that USP6’s ability to activate NK cells both intratumorally and systemically underlies its association with improved ES patient prognosis, which we seek to exploit for therapeutic benefit in future studies.

Citation Format: Kanika Jain, Ian C. Henrich, Laura Nicole Quick, Robert A. Young, Margaret M. Chou. Natural killer cells mediate tumor-inhibitory functions of USP6 in Ewing sarcoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3147.

Iris cysts: Varied presentations and review of literature

An iris cyst is a nonkeratinized squamous epithelial-lined space involving a layer of iris. The presentation of iris cyst can be variable-innocuous or presenting with secondary complications. The identification of whether the cyst is primary or secondary is important. The prognosis of primary iris cysts is good, as the majority does not require treatment and that of secondary iris cysts is much more capricious depending on their presentation. Their optimal management often poses a challenge for ophthalmologists. Here, we will present two cases of iris cysts with diverse presentation along with a review of the literature of this rare clinical entity.

AB0165 MALIGNANCY AS PREDOMINANT CAUSE OF DEATH IN RHEUMATOID ARTHRITIS: REVIEW OF DATA FROM ‘BASILDON EARLY ARTHRITIS COHORT’

Background

Rheumatoid arthritis is a chronic inflammatory autoimmune condition historically linked to increased mortality with predominant contribution from cardiovascular, respiratory, infectious and neoplastic causes. There is evidence of decreasing cardiovascular mortality through improvements in preventative and treatment strategies. Recent literature has also suggested overall improvement in RA-associated mortality attributed to contemporary advances in disease control. There is a need to assess if such outcomes are reflected in the real world setting and to identify elements that continue to promote poorer outcomes.

Objectives

To assess long-term outcome in patients diagnosed with rheumatoid arthritis from the ‘Early Arthritis Cohort’ at a district general hospital in UK.

Methods

A retrospective cohort study was conducted on 185 patients newly diagnosed with rheumatoid arthritis between 2009 & 2013. Patients fulfilling the ACR/EULAR 2010 criteria were included. Anonymised data from the Basildon Early Arthritis registry was analysed. Measured parameters included patient demographics, disease activity score (DAS28), treatment regime, development of co-morbidity & mortality.

Results

Complete data was available for analysis in 171 patients. This comprised 60 men & 111 women with median age of 57 years (IQR 47 - 67 years) and median follow-up time of 90 months (IQR 63 - 108 months). Thirty nine percent were current or ex-smokers. At baseline, 40% of patients had DAS28 score > 5.1, this reduced to 2.5% at time of their last follow up. 74% of patients were in clinical remission at last follow up with 11.7% achieving drug-free remission, 40.4% remaining on single csDMARD, 29.8% on combination csDMARD & 18.1% on biologic therapy.

Analysis of new comorbidities revealed cancer burden of 12.9% (22/171) with lung cancer having highest incidence (n= 9). Other comorbidities recorded were cardiovascular 11.1% (19/171), pulmonary 5.8% (10/171) and cerebrovascular disease 5.3% (9/171).

A crude mortality rate of 19.3% (33/171) was observed in our cohort over a median period of 7.5 years follow-up. The incidence mortality rate was 174/10,000 person-years of follow-up and standardised mortality ratio was 2.09 (95% CI 1.44 – 2.86). Majority of patients died five or more years after initial diagnosis (67%) with most deaths occurring in the 6th year after disease onset. Patients in the mortality group had higher disease activity scores at their last follow-up compared to the remaining cohort (p=0.017).

More deaths were recorded from underlying malignancy 7.6% (n= 13) than with cardiovascular disease 4.7% (n= 8). Eight out of 13 cases were identified as lung cancer deaths. Breast, bladder, pancreatic and ovarian cancer constituted remaining cases. Other causes of death were from chronic obstructive pulmonary disease (n= 3), dementia/frailty (n = 3), interstitial lung disease (n= 2), infection (n= 2), stroke (n = 1) and chronic liver disease (n= 1).

Conclusion

Despite achieving remission in majority of patients, long-term analysis reveals that mortality in this cohort is significantly elevated compared to the general population. To best of our knowledge this is the first real-world study showing malignancy as the predominant cause of morbidity and mortality in rheumatoid arthritis.

References

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Disclosure of Interests

None declared

The Escherichia coli serS gene promoter region overlaps with the rarA gene

Deletion of the entire gene encoding the RarA protein of Escherichia coli results in a growth defect and additional deficiencies that were initially ascribed to a lack of RarA function. Further work revealed that most of the effects reflected the presence of sequences in the rarA gene that affect expression of the downstream gene, serS. The serS gene encodes the seryl aminoacyl-tRNA synthetase. Decreases in the expression of serS can trigger the stringent response. The sequences that affect serS expression are located in the last 15 nucleotides of the rarA gene.

A guide to molecular and functional investigations of platelets to bridge basic and clinical sciences

Platelets have been shown to be associated with pathophysiological process beyond thrombosis, demonstrating critical additional roles in homeostatic processes, such as immune regulation, and vascular remodeling. Platelets themselves can have multiple functional states and can communicate and regulate other cells including immune cells and vascular smooth muscle cells, to serve such diverse functions. Although traditional platelet functional assays are informative and reliable, they are limited in their ability to unravel platelet phenotypic heterogeneity and interactions. Developments in methods such as electron microscopy, flow cytometry, mass spectrometry, and 'omics' studies, have led to new insights. In this Review, we focus on advances in platelet biology and function, with an emphasis on current and promising methodologies. We also discuss technical and biological challenges in platelet investigations. Using coronavirus disease 2019 (COVID-19) as an example, we further describe the translational relevance of these approaches and the possible 'bench-to-bedside' utility in patient diagnosis and care.

Iridocorneal Endothelial Syndrome with Coexisting Macular Edema and Neurosensory Detachment: An Unusual Case Report

The iridocorneal endothelial (ICE) syndrome is a sporadic, unilateral condition characterized by abnormalities of the cornea, anterior chamber angle, and iris affecting middle-aged women (3rd to 5th decade). It consists of three variants: progressive iris atrophy, Cogan–Reese syndrome—diffuse nevus or iris nodules, and Chandler syndrome—corneal endothelial abnormalities leading to corneal edema. This syndrome has an abnormal corneal endothelial cell layer (proliferative endotheliopathy), which migrates across the angle and onto the surface of the iris. It is a potentially blinding condition as a result of secondary glaucoma and/or corneal decompensation. Although few case reports have shown an association of ICE syndrome with macular edema; however, our case was unique in the sense that it was associated with neurosensory detachment (NSD). It can be suggested that PG analogs are not a good idea to be prescribed for secondary glaucoma management in patients with ICE syndrome as it can predispose to the development of macular edema with NSD.

How to cite this article: Dubey S, Jain K, Singh S, et al. Iridocorneal Endothelial Syndrome with Coexisting Macular Edema and Neurosensory Detachment: An Unusual Case Report. J Curr Glaucoma Pract 2021;15(3):149–152.

O-006 Diagnosis debate – USG vs endoscopy

MULLERIAN ANOMAIES – DEBATE USG OR ENDOSCOPY

Mullerian duct anomalies are a complex spectrum of congenital anomalies resulting from defective fusion or canalization leading to different uterine anomalies. Early detection and proper diagnosis of uterine anomalies are paramount for proper management. Outflow obstruction defects like transvers septal defects or non canalised functional horn present early with complaint of pain while rest of patients present with amenorrhoea , infertility, repeated first-trimester abortion, fetal intrauterine growth restriction, and obstetric complications.The prevalence of uterine malformations is variable depending on the population studied , 0.4% , 4 % respectively in the general population and in infertile women while a high prevalence between 3 and 38% is reported in patients with repeated spontaneous miscarriages.

Imaging plays an important role in diagnosis and treatment planning in mullerian duct anomalies. There are different imaging and endoscopic modalities that can be used for the diagnosis and confirmation of uterine malformations. All modalities are having limitations and one need to select and combine various modalities depending on the clinical presentation of patient and pelvic examination. In younger patients or acute cases, trans abdominal ultrasonography (US) is the preferred method because it is readily available, inexpensive, and rapid and does not use ionizing radiation. However it may not give the complete picture because of poor demarcation especially in fatty patient and owing to complex nature of defects , Field-of-view restrictions with US, patient body habitus, and artefact from bowel gas. Pelvic magnetic resonance imaging (MRI) is an excellent tool in the diagnosis of Mullerian duct anomalies due to high soft tissue resolution. But it is more expensive and less available. 3D ultrasound may be a valid alternative to pelvic MRI as It is less expensive and better tolerated by patients however in doubtful cases of complex nature , hysteroscopy combined with laparoscopy may be considered to confirm the diagnosis. Another advantage of endoscopy is the opportunity to correct the defect in the same sitting in most of the cases.

Hysterosalpingography (HSG) and hysteroscopy are considered good modalities to assess the uterine cavity. Hysteroscopy provide the direct visualisation of the defect and considered as gold standard for cavity evaluation in doubtful cases of septate and bicornuate uterus and for simultaneous correction. However outer contour cannot be visualised so one need to use laparoscopy for complete evaluation which is a major drawback. Three-dimensional transvaginal sonography provides image quality like those provided by MRI and is being extensively used for diagnosis of all sorts of mullerian defects. it has got the advantage of realtime imaging which is helpful in distorted pelvic anatomy , visualisation of outer contour is possible ,which is considered very important to differentiate between bicornuate and septate uterus and unicornuate uterus with rudimentary horn. however it may not be possible in all cases to get a definitive diagnosis inspite of using a high end 3D machine specially in presence of artefacts , distorted contour and retroverted uterus. In such cases both modalities including MRI and endoscopy may be required to reach to a definitive diagnosis.

It can be concluded that primary imaging tool is still 2d ultrasound but 3D TVS should be included in all suspected anomalies along with complete careful pelvic examination to corroborate the findings of USG. In doubt ful or complex cases, MRI should be performed particularly for cervical and vaginal atresia and septum. endoscopy should be reserved for all doubtful cases for confirmation and for acute cases where a corrective surgery can also be planned to relieve the distress.

Low-dose Aspirin prevents hypertension and cardiac fibrosis when thromboxane A2 is unrestrained

Enhanced platelet activation has been reported in patients with essential hypertension and heart failure. The possible contribution of platelet-derived thromboxane (TX)A2 in their pathophysiology remains unclear. We investigated the systemic TXA2 biosynthesis in vivo and gene expression of its receptor TP in 22 essential hypertension patients and a mouse model of salt-sensitive hypertension. The contribution of platelet TXA2 biosynthesis on enhanced blood pressure (BP) and overload-induced cardiac fibrosis was explored in mice by treating with low-dose Aspirin, resulting in selective inhibition of platelet cyclooxygenase (COX)-1-dependent TXA2 generation. In essential hypertensive patients, systemic biosynthesis of TXA2 [assessed by measuring its urinary metabolites (TXM) reflecting predominant platelet source] was enhanced together with higher gene expression of circulating leukocyte TP and TGF-β, vs. normotensive controls. Similarly, in hypertensive mice with prostacyclin (PGI2) receptor (IP) deletion (IPKO) fed with a high-salt diet, enhanced urinary TXM, and left ventricular TP overexpression were detected vs. normotensive wildtype (WT) mice. Increased cardiac collagen deposition and profibrotic gene expression (including TGF-β) was found. Low-dose Aspirin administration caused a selective inhibition of platelet TXA2 biosynthesis and mitigated enhanced blood pressure, cardiac fibrosis, and left ventricular profibrotic gene expression in IPKO but not WT mice. Moreover, the number of myofibroblasts and extravasated platelets in the heart was reduced. In cocultures of human platelets and myofibroblasts, platelet TXA2 induced profibrotic gene expression, including TGF-β1. In conclusion, our results support tailoring low-dose Aspirin treatment in hypertensive patients with unconstrained TXA2/TP pathway to reduce blood pressure and prevent early cardiac fibrosis.

RecA-independent recombination: Dependence on the Escherichia coli RarA protein

Most, but not all, homologous genetic recombination in bacteria is mediated by the RecA recombinase. The mechanistic origin of RecA-independent recombination has remained enigmatic. Here, we demonstrate that the RarA protein makes a major enzymatic contribution to RecA-independent recombination. In particular, RarA makes substantial contributions to intermolecular recombination and to recombination events involving relatively short (<200 bp) homologous sequences, where RecA-mediated recombination is inefficient. The effects are seen here in plasmid-based recombination assays and in vivo cloning processes. Vestigial levels of recombination remain even when both RecA and RarA are absent. Additional pathways for RecA-independent recombination, possibly mediated by helicases, are suppressed by exonucleases ExoI and RecJ. Translesion DNA polymerases may also contribute. Our results provide additional substance to a previous report of a functional overlap between RecA and RarA.

Ultrasound-guided sacral multifidus plane block for analgesia following excision of sacrococcygeal teratoma in two neonates

Peri-operative pain management in the neonate with a sacrococcygeal teratoma poses significant challenges to the anaesthetist. Involvement of the sacrococcygeal area by the tumour often prevents the use of conventional regional anaesthetic techniques such as caudal or epidural analgesia, with a subsequent reliance on intravenous opioids and paracetamol. Since opioids are associated with respiratory depression, constipation and urinary retention, there is high incidence of opiophobia with consequent inappropriate dosage prescription, particularly in the paediatric population. We describe the use of an ultrasound-guided sacral multifidus plane block in two neonates undergoing surgical excision of sacrococcygeal teratoma. The block is technically easy to perform and also avoids traversing critical structures. Hence, it may be regarded as a promising analgesic technique for painful interventions in the sacrococcygeal area.

Ubiquitin-Specific Protease 6 Functions as a Tumor Suppressor in Ewing Sarcoma through Immune Activation

Ewing sarcoma is the second most common pediatric bone cancer, with a 5-year survival rate for metastatic disease of only 20%. Recent work indicates that survival is strongly correlated with high levels of tumor-infiltrating lymphocytes (TIL), whose abundance is associated with IFN-inducible chemokines CXCL10 and CCL5. However, the tumor-intrinsic factors that drive chemokine production and TIL recruitment have not been fully elucidated. We previously showed that ubiquitin-specific protease 6 (USP6) directly deubiquitinates and stabilizes Jak1, thereby inducing an IFN signature in Ewing sarcoma cells. Here, we show that this gene set comprises chemokines associated with immunostimulatory, antitumorigenic functions, including CXCL10 and CCL5. USP6 synergistically enhanced chemokine production in response to exogenous IFN by inducing surface upregulation of IFNAR1 and IFNGR1. USP6-expressing Ewing sarcoma cells stimulated migration of primary human monocytes and T lymphocytes and triggered activation of natural killer (NK) cells in vitro. USP6 inhibited Ewing sarcoma xenograft growth in nude but not NSG mice and was accompanied by increased intratumoral chemokine production and infiltration and activation of NK cells, dendritic cells, and macrophages, consistent with a requirement for innate immune cells in mediating the antitumorigenic effects of USP6. High USP6 expression in patients with Ewing sarcoma was associated with chemokine production, immune infiltration, and improved survival. This work reveals a previously unrecognized tumor-suppressive function for USP6, which engenders an immunostimulatory microenvironment through pleiotropic effects on multiple immune lineages. This further raises the possibility that USP6 activity may be harnessed to create a "hot" tumor microenvironment in immunotherapy. SIGNIFICANCE: This study reveals a novel tumor-suppressive function for USP6 by inducing an immunostimulatory microenvironment, suggesting that USP6 activity may be exploited to enhance immunotherapy regimens.

Light-induced energy transfer followed by electron transfer in axially co-ordinated benzothiazole tethered zinc porphyrin-fullero[C60/C70]pyrrolidine triads

Benzothiazole (BTZ)-zinc porphyrin (ZnP) dyads, Dyad-1 and Dyad-2 connected together with two different spacers, ester and ethoxy esters, were synthesized and light induced energy and electron transfer events were investigated. Within these dyads, due to the spectral overlap of the BTZ emission with the ZnP absorption, a selective photoexcitation of BTZ at 325 nm resulted in the photo-induced energy transfer (PEnT) from 1BTZ* to ZnP displaying the quenching of the BTZ emission followed by the concurrent appearance of the ZnP emission at 600 and 650 nm suggesting the formation of the 1ZnP* [Formula: see text]. 1BTZ*-ZnP [Formula: see text] BTZ-1ZnP*. When the dyads are titrated with imidazole appended fullero[C[Formula: see text]/C[Formula: see text]]pyrrolidines, four supramolecular triads, involving the axial co-ordination of the imidazole to the zinc center of the ZnP, were formed and the assembly formation was systematically monitored by the optical absorption technique. Cyclic voltammetry and the density functional theory calculations have revealed that, in these triads, the zinc porphyrin acts as an electron donor and fullerene moiety as the electron acceptor. Steady state fluorescence studies revealed that, upon selective excitation of the ZnP moiety at 550 nm, the emission of ZnP at 600 and 650 nm was quenched revealing the occurrence of photo-induced electron transfer (PET) from 1ZnP* to fullerene moiety leading to the formation of charge separated state [Formula: see text]. BTZ-1ZnP* : (ImC[Formula: see text] BTZ-ZnP[Formula: see text]:(ImC[Formula: see text]. More importantly, when the supramolecular triads were excited at 325 nm, the wavelength at which the BTZ absorbs predominantly, the emission of the BTZ moiety which was quenched due to PEnT from 1BTZ* to ZnP followed by the PET from 1ZnP* to fullerene indicates the probability of occurrence of 1BTZ*-ZnP:(ImC[Formula: see text] [Formula: see text] BTZ-1ZnP*[Formula: see text]: (ImC[Formula: see text] BTZ-ZnP[Formula: see text]:(ImC[Formula: see text].

Thrombocytopathy and endotheliopathy: crucial contributors to COVID-19 thromboinflammation

The core pathology of coronavirus disease 2019 (COVID-19) is infection of airway cells by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that results in excessive inflammation and respiratory disease, with cytokine storm and acute respiratory distress syndrome implicated in the most severe cases. Thrombotic complications are a major cause of morbidity and mortality in patients with COVID-19. Patients with pre-existing cardiovascular disease and/or traditional cardiovascular risk factors, including obesity, diabetes mellitus, hypertension and advanced age, are at the highest risk of death from COVID-19. In this Review, we summarize new lines of evidence that point to both platelet and endothelial dysfunction as essential components of COVID-19 pathology and describe the mechanisms that might account for the contribution of cardiovascular risk factors to the most severe outcomes in COVID-19. We highlight the distinct contributions of coagulopathy, thrombocytopathy and endotheliopathy to the pathogenesis of COVID-19 and discuss potential therapeutic strategies in the management of patients with COVD-19. Harnessing the expertise of the biomedical and clinical communities is imperative to expand the available therapeutics beyond anticoagulants and to target both thrombocytopathy and endotheliopathy. Only with such collaborative efforts can we better prepare for further waves and for future coronavirus-related pandemics.

Iridoschisis: Spectrum of Presentation

PURPOSE:

The purpose of the study was to report a small case series of patients with iridoschisis seen at our hospital over a period of 5 years.

METHODS:

Retrospective review of all those files over the past 5 years whereby the diagnosis of iridoschisis/iris atrophy/iris fibrils in anterior chamber (AC) was made.

RESULTS:

In our case series, the average age at presentation was 49 years (range: 23–85 years). The pathology was bilateral in 57% of patients in our series. Our most common presentations were angle closure glaucoma and cataract. Younger individuals can also manifest iridoschisis.

CONCLUSION:

The iridoschisis can be an incidental finding, and gonioscopy should be performed in all the cases, as occludable or synechiael angle closure may be present in these cases.

Porphyrin bearing phenothiazine pincers as hosts for fullerene binding via concave–convex complementarity: synthesis and complexation study

Free base porphyrin hosts, m-(PTZ)4-H2P and p-(PTZ)4-H2P, tethered with four phenothiazine moieties at the meso-position via a flexible ethoxy phenyl linker were synthesized and used for the selective complexation of fullerenes, C60 and C70.

Singapore Undiagnosed Disease Program: Genomic Analysis aids Diagnosis and Clinical Management

OBJECTIVE

Use next-generation sequencing (NGS) technology to improve our diagnostic yield in patients with suspected genetic disorders in the Asian setting.

DESIGN

A diagnostic study conducted between 2014 and 2019 (and ongoing) under the Singapore Undiagnosed Disease Program. Date of last analysis was 1 July 2019.

SETTING

Inpatient and outpatient genetics service at two large academic centres in Singapore.

PATIENTS

Inclusion criteria: patients suspected of genetic disorders, based on abnormal antenatal ultrasound, multiple congenital anomalies and developmental delay.

EXCLUSION CRITERIA

patients with known genetic disorders, either after clinical assessment or investigations (such as karyotype or chromosomal microarray).

INTERVENTIONS

Use of NGS technology-whole exome sequencing (WES) or whole genome sequencing (WGS).

MAIN OUTCOME MEASURES

(1) Diagnostic yield by sequencing type, (2) diagnostic yield by phenotypical categories, (3) reduction in time to diagnosis and (4) change in clinical outcomes and management.

RESULTS

We demonstrate a 37.8% diagnostic yield for WES (n=172) and a 33.3% yield for WGS (n=24). The yield was higher when sequencing was conducted on trios (40.2%), as well as for certain phenotypes (neuromuscular, 54%, and skeletal dysplasia, 50%). In addition to aiding genetic counselling in 100% of the families, a positive result led to a change in treatment in 27% of patients.

CONCLUSION

Genomic sequencing is an effective method for diagnosing rare disease or previous 'undiagnosed' disease. The clinical utility of WES/WGS is seen in the shortened time to diagnosis and the discovery of novel variants. Additionally, reaching a diagnosis significantly impacts families and leads to alteration in management of these patients.

Efficacy of influenza vaccine (Fluvax) in cancer patients on treatment: a prospective single arm, open-label study

PURPOSE

Influenza virus infection has significant morbidity and mortality in patients with medical co-morbidities who are also immunosuppressed. The efficacy of the seasonal influenza vaccine has not been well studied in patients receiving chemotherapy. We assessed the efficacy of seasonal influenza vaccine in patients with non-haematological malignancy on active treatment (chemotherapy and targeted therapy).

METHODS

A prospective single arm, open label study with 53 patients with non-haematological cancers recruited during the 2011 and 2012 influenza seasons. Participants had one dose of 2011/2012 trivalent vaccine containing strains A/California/7/2009(H1N1), A/Perth/16/2009 (H3N2) and B/Brisbane/60/2008 (Fluvax) prior to or in-between treatment cycles. Haemagglutination inhibition antibody (HIA) titres in serum were measured at baseline 3, 6 and 24 weeks. Primary endpoint: seroconversion rate (SCR) at 3 weeks. Secondary endpoints: late SCR at 6 weeks. rate of sustained sero-protection titres (SPR) at 24 weeks. Seroconversion was defined as postvaccination ≥ 4-fold increase in HIA titre and sero-protection defined as a HIA ≥ 1:40.

RESULTS

The SCR at 3 weeks were 35%, 30% and 22.5% to the H1N1, H3N2 and B/Bris strains, respectively. There were no new cases of late SC at 6 weeks or 24 weeks. The SPR at 3 weeks were 72.5%, 65% and 40%, respectively, to H1N1, H3N2 and B/Bris. The SPR at 24 weeks to H1N1, H3N2 and B/Bris were 40%, 52.5% and 17.5%, respectively.

CONCLUSIONS

Patients on various solid tumour treatments achieve sero-protection rate congruent with the general population. The sero-protection HIA titres were not sustained at 24 weeks postvaccination.

openPrimeR for multiplex amplification of highly diverse templates

To study the diversity of immune receptors and pathogens, multiplex PCR has become a central approach in research and diagnostics. However, insufficient primer design against highly diverse templates often prevents amplification and therefore limits the correct understanding of biological processes. Here, we present openPrimeR, an R-based tool for evaluating and designing multiplex PCR primers. openPrimeR provides a functional and intuitive interface and uses either a greedy algorithm or an integer linear program to compute the minimal set of primers that performs full target coverage. As proof of concept, we used openPrimeR to find optimal primer sets for the amplification of highly mutated immunoglobulins. Comprehensive analyses on specifically generated immunoglobulin variable gene segment libraries resulted in the composition of highly effective primer sets (oPR-IGHV, oPR-IGKV and oPR-IGLV) that demonstrated to be particularly suitable for the isolation of novel human antibodies.

Characterizing autonomic response to arousing visual-auditory multi-modal task in Autism Spectrum Disorder (ASD)

Sensory abnormalities are widespread in Autism Spectrum Disorder (ASD). However, their definition is still quite subjective and vague. Here we propose a novel approach for characterization of Autonomic Nervous System responses to sensory stimulation based on electrocardiogram (ECG) assessment. In particular, we develop a preliminary study where autonomic responses of both autistic (ASD = 5) and neurotypical (NT = 5) participants have been evaluated in terms of changes in responsiveness to repeated stimuli. Autonomic control has been estimated via high-frequency heart rate variability (HF-HRV) and low-frequency HRV (LF-HRV). Results show significant differences among groups for the HRV measures (p value = 0.0158), supported by expected changes of HF (p value = 0.0079) and LF (p value = 0.0079) trends over stimulations. We thus conclude that an overall decrease in autonomic arousal can give important insights for devising new habituation metrics in NT and ASD individuals.

Role of Platelet Mitochondria: Life in a Nucleus-Free Zone

Platelets are abundant, small, anucleate circulating cells, serving many emerging pathophysiological roles beyond hemostasis; including active critical roles in thrombosis, injury response, and immunoregulation. In the absence of genomic DNA transcriptional regulation (no nucleus), platelets require strategic prepackaging of all the needed RNA and organelles from megakaryocytes, to sense stress (e.g., hyperglycemia), to protect themselves from stress (e.g., mitophagy), and to communicate a stress response to other cells (e.g., granule and microparticle release). Distinct from avian thrombocytes that have a nucleus, the absence of a nucleus allows the mammalian platelet to maintain its small size, permits morphological flexibility, and may improve speed and efficiency of protein expression in response to stress. In the absence of a nucleus, platelet lifespan of 7–10 days, is largely determined by the mitochondria. The packaging of 5–8 mitochondria is critical in aerobic respiration and yielding metabolic substrates needed for function and survival. Mitochondria damage or dysfunction, as observed with several disease processes, results in greatly attenuated platelet survival and increased risk for thrombovascular events. Here we provide insights into the emerging roles of platelets despite the lack of a nucleus, and the key role played by mitochondria in platelet function and survival both in health and disease.

Patient Involvement in Decision-Making: An Important Parameter for Better Patient Experience-An Observational Study (STROBE Compliant)

Background and Aim:

Preferences of service users is an important consideration for developing health-care services. This study aimed to assess the experiences of the patients with substance use disorders who were admitted to a tertiary health-care facility in India.

Method:

This cross-sectional sectional study recruited adult inpatients who stayed for a period of 7 days or more. The Picker Patient Experience questionnaire (PPE-15) was used to gather information about the views of the patients about the care received at the center.

Results:

Responses were available from 113 inpatients. Majority of the participants were males and were dependent on opioids. The experience was generally positive about being treated with respect and dignity and access to information. The participants were most satisfied with opportunity being given to discuss anxiety and fear about the condition or treatment (91.2% positive response) and least satisfied with differences in responses from doctors and nurses (43.4% positive response). Further attention seemed desired about communication with the staff and patients’ involvement in their own treatment-related decision-making.

Conclusion:

Efforts need to be made to involve patients in their own treatment-related decision-making and to improve communication with the treatment team. This might lead to better involvement in treatment process, which could enhance the treatment outcomes in this vulnerable population.

Mitochondrial MsrB2 serves as a switch and transducer for mitophagy

Mitophagy can selectively remove damaged toxic mitochondria, protecting a cell from apoptosis. The molecular spatial-temporal mechanisms governing autophagosomal selection of reactive oxygen species (ROS)-damaged mitochondria, particularly in a platelet (no genomic DNA for transcriptional regulation), remain unclear. We now report that the mitochondrial matrix protein MsrB2 plays an important role in switching on mitophagy by reducing Parkin methionine oxidation (MetO), and transducing mitophagy through ubiquitination by Parkin and interacting with LC3. This biochemical signaling only occurs at damaged mitochondria where MsrB2 is released from the mitochondrial matrix. MsrB2 platelet-specific knockout and in vivo peptide inhibition of the MsrB2/LC3 interaction lead to reduced mitophagy and increased platelet apoptosis. Pathophysiological importance is highlighted in human subjects, where increased MsrB2 expression in diabetes mellitus leads to increased platelet mitophagy, and in platelets from Parkinson's disease patients, where reduced MsrB2 expression is associated with reduced mitophagy. Moreover, Parkin mutations at Met192 are associated with Parkinson's disease, highlighting the structural sensitivity at the Met192 position. Release of the enzyme MsrB2 from damaged mitochondria, initiating autophagosome formation, represents a novel regulatory mechanism for oxidative stress-induced mitophagy.

Quality assurance in ophthalmic imaging

Quality assurance (QA) is the maintenance of a desired level of quality in a service, by means of attention to every stage of process of delivery. Correct image acquisition along with accurate and reproducible quantification of ophthalmic imaging is crucial for evaluating disease progression/stabilization, response to therapy, and planning proper management of these cases. QA includes development of standard operating procedures for the collection of data for ophthalmic imaging, proper functioning of the ophthalmic imaging equipment, and intensive training of technicians/doctors for the same. QA can be obtained during ophthalmic imaging by not only calibration and setting up of the instrument as per the manufacturer's specifications but also giving proper instructions to the patients in a language which they understand and by acquisition of good quality images. This review article will highlight on how to achieve QA in imaging which is commonly being used in ophthalmic practice.