High-Throughput Spectroscopy of Geometry-Tunable Arrays of Axial InGaAs Nanowire Heterostructures with Twin-Induced Carrier Confinement

Predicting the optical properties of large-scale ensembles of luminescent nanowire arrays that host active quantum heterostructures is of paramount interest for on-chip integrated photonic and quantum photonic devices. However, this has remained challenging due to the vast geometrical parameter space and variations at the single object level. Here, we demonstrate high-throughput spectroscopy on 16800 individual InGaAs quantum heterostructures grown by site-selective epitaxy on silicon, with varying geometrical parameters to assess uniformity/yield in luminescence efficiency, and emission energy trends. The luminescence uniformity/yield enhances significantly at prepatterned array mask opening diameters (d0) greater than 50 nm. Additionally, the emission energy exhibits anomalous behavior with respect to d0, which is notably attributed to rotational twinning within the InGaAs region, inducing significant energy shifts due to quantum confinement effects. These findings provide useful insights for mapping and optimizing the interdependencies between geometrical parameters and electronic/optical properties of widely tunable sets of quantum nanowire heterostructures.

Intraoperative parathyroid hormone assay benefits surgery for primary hyperparathyroidism when preoperative localisation is negative or not performed

INTRODUCTION

Parathyroid localisation is now routine before first-time surgery for patients with primary hyperparathyroidism (PHPT). The aim of this study was to investigate the contribution of intraoperative parathyroid hormone (PTH) (ioPTH) in patients in whom localisation was either not undertaken or negative for a tumour.

METHODS

This was a retrospective study of patients undergoing first-time parathyroidectomy for PHPT in a regional endocrine centre. Data were collected prospectively (Microsoft Excel) and the all-Wales electronic patient record portal was used to retrieve missing data. Statistical analysis appropriate for nonparametric data was undertaken, with statistical significance reached when p<0.05.

RESULTS

Between 1 July 2002 and 31 December 2022, 1,490 patients underwent a first-time parathyroidectomy for PHPT. Of this cohort, 1,133 patients had at least one positive imaging modality; the study group consisted of 343 patients that had negative imaging, and 13 that had no preoperative localisation. Patients with MEN-1 (n=26), an incorrect diagnosis (n=4), or less than six months follow-up (n=6) were excluded. Of the remaining 321, 106 patients underwent surgery without ioPTH (Group A), 215 cases with ioPTH (Group B). In Group B there were more women (170 female/45 male; 79% vs 67 female/37 male; 63% p=0.002, chi-squared), lower calcium (median [range] 2.77 [2.63-3.24] mmol/l; vs 2.85 [2.60-4.52] p=0.001) and lower PTH (12.0pmol/l [3.4-39.5] vs 14.4 [3.9-97.0] p=0.001) and smaller weights of resected tissue (320mg [50-9,000] vs 454 [46-8,280] p=0.02) (Student's t-test). The rate of multiple gland disease was similar (Group A 29%; Group B 27%). The rate of normocalcaemia at 6 months was significantly higher when ioPTH was used (Group B 202/215; 94% vs Group A 90/106; 85%) (p=0.014, chi-square test). The sensitivity and specificity of ioPTH was 98.5% [confidence interval (CI) 96.2-99.6] and 91.2% [80.7-97.0] (positive predictive value 99.9%, CI 93.6-100.0).

CONCLUSION

Despite milder hyperparathyroidism and smaller tumour weight, the outcome in patients in whom ioPTH was used was superior, with failure rates 2.5-fold higher in the cohort where ioPTH was not utilised. The results of this study demonstrate that ioPTH is a valuable adjunct for the surgeon in cases where localisation has failed or not been undertaken.

Prostate specific membrane antigen (PSMA) avid nonprostatic benign and malignant disease: a pictorial review

Prostate specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT) is revolutionising the management of prostate cancer (PC) in primary staging and assessment of biochemical recurrence (BCR) through its higher diagnostic accuracy compared to both conventional imaging and previously available PET radiopharmaceuticals. PSMA is a transmembrane glycoprotein, highly expressed in prostate cancer, with its extracellular domain the target for PSMA PET radiopharmaceuticals. However, PSMA expression is not prostate specific and resultant PSMA uptake on PET-CT is not restricted to pathologies arising from the prostate gland. The increasing use of PSMA PET-CT has revealed PSMA uptake in a variety of non-prostatic benign and malignant diseases, which adds complexity to PET-CT interpretation and subsequent clinical management. This pictorial review will provide a thorough knowledge and understanding of the comprehensive range of PSMA avid non-prostatic benign and malignant diseases demonstrable on PSMA PET-CT, whilst highlighting the complimentary nature of other imaging modalities.

Visualizing Viral RNA Packaging Signals in Action

Here we confirm, using genome-scale RNA fragments in assembly competition assays, that multiple sub-sites (Packaging Signals, PSs) across the 5' two-thirds of the gRNA of Satellite Tobacco Necrosis Virus-1 make sequence-specific contacts to the viral CPs helping to nucleate formation of its T = 1 virus-like particle (VLP). These contacts explain why natural virions only package their positive-sense genomes. Asymmetric cryo-EM reconstructions of these VLPs suggest that interactions occur between amino acid residues in the N-terminal ends of the CP subunits and the gRNA PS loop sequences. The base-paired stems of PSs also act non-sequence-specifically by electrostatically promoting the assembly of CP trimers. Importantly, alterations in PS-CP affinity result in an asymmetric distribution of bound PSs inside VLPs, with fuller occupation of the higher affinity 5' PS RNAs around one vertex, decreasing to an RNA-free opposite vertex within the VLP shell. This distribution suggests that gRNA folding regulates cytoplasmic genome extrusion so that the weakly bound 3' end of the gRNA, containing the RNA polymerase binding site, extrudes first. This probably occurs after cation-loss induced swelling of the CP-shell, weakening contacts between CP subunits. These data reveal for the first time in any virus how differential PS folding propensity and CP affinities support the multiple roles genomes play in virion assembly and infection. The high degree of conservation between the CP fold of STNV-1 and those of the CPs of many other viruses suggests that these aspects of genome function will be widely shared.

Use of federated learning to develop an artificial intelligence model predicting usable blastocyst formation from pre-ICSI oocyte images

RESEARCH QUESTION

Can federated learning be used to develop an artificial intelligence (AI) model for evaluating oocyte competence using two-dimensional images of denuded oocytes in metaphase II prior to intracytoplasmic sperm injection (ICSI)?

RESULTS

The oocyte AI model demonstrated area under the curve (AUC) up to 0.65 on two blind test datasets. High sensitivity for predicting competent oocytes (83-88%) was offset by lower specificity (26-36%). Exclusion of confounding biological variables (male factor infertility and maternal age ≥35 years) improved AUC up to 14%, primarily due to increased specificity. AI score correlated with size of the zona pellucida and perivitelline space, and ooplasm appearance. AI score also correlated with blastocyst expansion grade and morphological quality. The sum of AI scores from oocytes in group culture images predicted the formation of two or more usable blastocysts (AUC 0.77).

CONCLUSION

An AI model to evaluate oocyte competence was developed using federated learning, representing an essential step in protecting patient data. The AI model was significantly predictive of oocyte competence, as defined by usable blastocyst formation, which is a critical factor for IVF success. Potential clinical utility ranges from selective oocyte fertilization to guiding treatment decisions regarding additional rounds of oocyte retrieval.

DESIGN

In total, 10,677 oocyte images with associated metadata were collected prospectively by eight IVF clinics across six countries. AI training used federated learning, where data were retained on regional servers to comply with data privacy laws. The final AI model required a single image as input to evaluate oocyte competence, which was defined by the formation of a usable blastocyst (≥expansion grade 3 by day 5 or 6 post ICSI).

First Simultaneous Measurement of Differential Muon-Neutrino Charged-Current Cross Sections on Argon for Final States with and without Protons Using MicroBooNE Data

We report the first double-differential neutrino-argon cross section measurement made simultaneously for final states with and without protons for the inclusive muon neutrino charged-current interaction channel. The proton kinematics of this channel are further explored with a differential cross section measurement as a function of the leading proton's kinetic energy that extends across the detection threshold. These measurements use data collected with the MicroBooNE detector from 6.4×10^{20} protons on target from the Fermilab booster neutrino beam with a mean neutrino energy of ∼0.8  GeV. Extensive data-driven model validation utilizing the conditional constraint formalism is employed. This motivates enlarging the uncertainties with an empirical reweighting approach to minimize the possibility of extracting biased cross section results. The extracted nominal flux-averaged cross sections are compared to widely used event generator predictions revealing severe mismodeling of final states without protons for muon neutrino charged-current interactions, possibly from insufficient treatment of final state interactions. These measurements provide a wealth of new information useful for improving event generators which will enhance the sensitivity of precision measurements in neutrino experiments.

Tracheobronchial foreign body aspiration in children in Soweto, South Africa: A retrospective descriptive study

Background

Airway foreign bodies are a common cause of accidental death in children. Tracheobronchial foreign body aspiration (FBA) can result in severe immediate and long-term complications if the foreign body is not identified and removed. Little is known about the burden of tracheobronchial FBA in the Soweto area, south of Johannesburg, South Africa. Objectives. To describe the burden and clinical characteristics of tracheobronchial FBA in hospitalised children in a tertiary-level hospital in Johannesburg.

Methods

This was a retrospective, single-centre, descriptive study of children aged <10 years who presented to Chris Hani Baragwanath Academic Hospital from 1 January 2011 to 31 December 2020. Children with FBA were identified from the paediatric pulmonology and paediatric surgery databases using the relevant International Statistical Classification of Diseases and Related Health Problems, 10th revision (ICD-10), codes (T17.4 and T17.5). Clinical and radiological data were extracted from medical records and the databases.

Results

Forty-seven children with FBA were identified during the study period. Overall, the incidence of FBA among children aged <10 years of age was 1.42 per 100 000 person-years (95.0% confidence interval 1.04 - 1.88). FBA occurred more commonly in males (66.0%; n=31), and the mean (standard deviation) age at presentation was 68 (28.2) months. Most of the children (42.6%) were in the 7 - <10-year age group, followed by the 5 - <7-year age group (27.7%). Chronic respiratory symptoms were reported in one-third of the children, and a history of witnessed FBA was reported in only 59.6% of cases. Inorganic foreign bodies (n=29; 61.7%) were aspirated more commonly than organic foreign bodies; these included metal objects such as pins or springs (21.3%), toy parts (17.0%), pen or pencil lids/stoppers (12.8%) and plastic objects (6.4%).

Conclusion

Our study highlights the fact that tracheobronchial FBA is prevalent in school-aged children, and public safety campaigns targeted at this age group are warranted. Furthermore, to prevent sequelae, a high index of suspicion in required in children with respiratory symptoms that fail to respond to appropriate therapy.

Study synopsis

What the study adds. Our study demonstrated that tracheobronchial foreign body aspiration (FBA) was most prevalent in school-aged children (7 - <10 years of age), which is in contrast to studies that have reported a high prevalence in children aged <3 years. Chronic respiratory symptoms were reported in only a third of the children, and a history of witnessed FBA was reported in only 59.6%. Chest radiographs were normal in a high proportion of cases in which a chest radiograph was done (56.3%). Inorganic foreign bodies were aspirated more commonly than organic foreign bodies.Implications of the findings. Public safety campaigns should be targeted at school-aged children in Soweto, South Africa. Clinicians should investigate children with respiratory symptoms suggestive of FBA, even if a history is not forthcoming. Furthermore, to prevent long-term respiratory sequelae, a high index of suspicion in required in children with respiratory symptoms that fail to respond to appropriate therapy.

First Search for Dark-Trident Processes Using the MicroBooNE Detector

We present a first search for dark-trident scattering in a neutrino beam using a dataset corresponding to 7.2×10^{20} protons on target taken with the MicroBooNE detector at Fermilab. Proton interactions in the neutrino target at the main injector produce π^{0} and η mesons, which could decay into dark-matter (DM) particles mediated via a dark photon A^{'}. A convolutional neural network is trained to identify interactions of the DM particles in the liquid-argon time projection chamber (LArTPC) exploiting its imagelike reconstruction capability. In the absence of a DM signal, we provide limits at the 90% confidence level on the squared kinematic mixing parameter ϵ^{2} as a function of the dark-photon mass in the range 10≤M_{A^{'}}≤400  MeV. The limits cover previously unconstrained parameter space for the production of fermion or scalar DM particles χ for two benchmark models with mass ratios M_{χ}/M_{A^{'}}=0.6 and 2 and for dark fine-structure constants 0.1≤α_{D}≤1.

Effectiveness and diagnostic accuracy of teledermatology for the assessment of skin conditions

BACKGROUND

Teledermatology provides a platform for swift specialist advice without the potential need for face-to-face review. Our objectives were to investigate the effectiveness, accuracy and diagnostic concordance of the platform with regard to the remote management of skin conditions.

METHODS

We undertook a single-centre, retrospective chart review over a 1-year period, comprising a total of 1703 teledermatology referrals. Two physicians independently assessed the diagnostic concordance between telederm diagnosis (TD), in-person diagnosis (ID) and histopathological diagnosis (HD).

RESULTS

There were a total of 1703 TD referrals, of which 341 were rejected, leaving 1362 referrals for evaluation. Sixty-five per cent of these referrals were managed remotely and discharged with advice, although 4.6% of these were later re-referred for an in-person review. A total of 20% of referrals were rejected, of which the majority was due to a lack of appropriate imaging. The total concordance of TD compared to ID was 76.4%. When comparing the TD and ID/HD, we obtained a Kappa value of 0.636 indicating substantial agreement. In terms of accuracy, there were 49 biopsy-proven skin cancers picked up by the service in this cohort of data. Of these, 61.2% were given an accurate diagnosis on first impression via teledermatology, 14.3% were given a different diagnosis but correctly categorised as skin cancer and 24.5% could not be assessed; however, they were triaged and escalated based upon clinical suspicion.

CONCLUSION

Our study demonstrates that teledermatology is an effective platform in terms of diagnosis and remote management, with adequate diagnostic accuracy and concordance to in-person diagnosis.

Social Risk Factors and Racial and Ethnic Disparities in Health Care Resource Utilization Among Medicare Advantage Beneficiaries With Psychiatric Disorders

The intersection of social risk and race and ethnicity on mental health care utilization is understudied. This study examined disparities in health care treatment, adjusting for clinical need, among 25,780 Medicare Advantage beneficiaries with a diagnosis of a psychiatric disorder. We assessed contributions to disparities from racial and ethnic differences in the composition and returns of social risk variables. Black and Hispanic beneficiaries had lower rates of mental health outpatient visits than Whites. Assessing composition, Black and Hispanic beneficiaries experienced greater financial, food, and housing insecurity than White beneficiaries, factors associated with greater mental health treatment. Assessing returns, food insecurity was associated with an exacerbation of Hispanic-White disparities. Health care systems need to address the financial, food and housing insecurity of racial and ethnic minority groups with psychiatric disorder. Accounting for racial and ethnic differences in social risk adjustment-based payment reforms has significant implications for provider reimbursement and outcomes.

Unintended consequences of using collars with occipital extensions in neck support - Snapshot assessment at the largest tertiary spinal referral centre in the UK

INTRODUCTION

Upper cervical spine fractures are commonplace in the elderly following low energy trauma. These injuries carry high mortality rates, similar to patients sustaining hip fractures. A key aspect affecting clinical outcome is effective management in the first 12 weeks following injury. This study aims to assess the understanding of healthcare staff that may be required to care for such patients.

MATERIALS AND METHODS

A survey was carried out over a single day at the UK's largest Spine Specialist referral centre (Salford Royal Foundation Trust, SRFT) assessing the understanding of healthcare staff of the term, 'Collar with occipital extension', by asking staff to identify the safe position of the neck when looking at clinical images of a model in a collar in various different neck positions. The participants demographics were then taken, including profession, grade, spinal/post graduate experience, if English is their first language and their understanding of the term 'Collar with occipital extension'.

RESULTS

102 participants were interviewed and the results showed almost half (45.1%) of participants selecting an incorrect hyperextended neck to be a safe position for conservative treatment and only 37.3% selecting the neutral position as satisfactory. The only positive predictors identified for those selective the neutral safe cervical spine alignment was if participants had >5 years of previous spinal experience (p = 0.0006) or if they understood the term 'Collar with occipital extension' to be describing the collar component (p = 0.000013) and not neck position.

CONCLUSION

Management of spinal injuries are classically poorly managed in non-spinal centres, possibly due to the lack of training and understanding within the spinal speciality. This study shows the importance of clearly communicating with referring hospitals exactly how to conservatively manage patients with high cervical injuries to best improve clinical outcome.

First Measurement of η Meson Production in Neutrino Interactions on Argon with MicroBooNE

We present a measurement of η production from neutrino interactions on argon with the MicroBooNE detector. The modeling of resonant neutrino interactions on argon is a critical aspect of the neutrino oscillation physics program being carried out by the DUNE and Short Baseline Neutrino programs. η production in neutrino interactions provides a powerful new probe of resonant interactions, complementary to pion channels, and is particularly suited to the study of higher-order resonances beyond the Δ(1232). We measure a flux-integrated cross section for neutrino-induced η production on argon of 3.22±0.84(stat)±0.86(syst) 10^{-41}  cm^{2}/nucleon. By demonstrating the successful reconstruction of the two photons resulting from η production, this analysis enables a novel calibration technique for electromagnetic showers in GeV accelerator neutrino experiments.

Ischemia but no obstructive coronary artery disease: more than meets the eye

Symptomatic women with angina are more likely to have ischemia with no obstructive coronary arteries (INOCA) compared to men. In both men and women, the finding of INOCA is not benign and is associated with adverse cardiovascular events, including myocardial infarction, heart failure and angina hospitalizations. Women with INOCA have more angina and a lower quality of life compared to men, but they are often falsely reassured because of a lack of obstructive coronary artery disease (CAD) and a perception of low risk. Coronary microvascular dysfunction (CMD) is a key pathophysiologic contributor to INOCA, and non-invasive imaging methods are used to detect impaired microvascular flow. Coronary vasospasm is another mechanism of INOCA, and can co-exist with CMD, but usually requires invasive coronary function testing (CFT) with provocation testing for a definitive diagnosis. In addition to traditional heart disease risk factors, inflammatory, hormonal and psychological risk factors that impact microvascular tone are implicated in INOCA. Treatment of risk factors and use of anti-atherosclerotic and anti-anginal medications offer benefit. Increasing awareness and early referral to specialized centers that focus on INOCA management can improve patient-oriented outcomes. However, large, randomized treatment trials to investigate the impact on major adverse cardiovascular events (MACE) are needed. In this focused review, we discuss the prevalence, pathophysiology, presentation, diagnosis and treatment of INOCA.

Search for Heavy Neutral Leptons in Electron-Positron and Neutral-Pion Final States with the MicroBooNE Detector

We present the first search for heavy neutral leptons (HNLs) decaying into νe^{+}e^{-} or νπ^{0} final states in a liquid-argon time projection chamber using data collected with the MicroBooNE detector. The data were recorded synchronously with the NuMI neutrino beam from Fermilab's main injector corresponding to a total exposure of 7.01×10^{20} protons on target. We set upper limits at the 90% confidence level on the mixing parameter |U_{μ4}|^{2} in the mass ranges 10≤m_{HNL}≤150  MeV for the νe^{+}e^{-} channel and 150≤m_{HNL}≤245  MeV for the νπ^{0} channel, assuming |U_{e4}|^{2}=|U_{τ4}|^{2}=0. These limits represent the most stringent constraints in the mass range 35 Collapse

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Patterns of online information use prior to middle-ear surgery: a retrospective cohort study

OBJECTIVE

This study aimed to identify what proportion of middle-ear surgery patients utilise the internet for information and to characterise which resources and media formats are used and for what durations.

METHOD

A single-arm, retrospective cohort study was performed using an online survey of English-speaking patients who underwent middle-ear surgery over a three-year period across two otology practices.

RESULTS

Of 260 invitees, 165 responded. A total of 122 used online resources: 9.8 per cent used online resources for less than 15 minutes, 27.0 per cent used them for 15 to 29 minutes, 27.0 per cent used them for 30 to 59 minutes and 36.1 per cent used them for 60 minutes or more. Of online users with complete responses (108 of 122), the most used resources (used for 12 minutes or more) were: written information (73.1 per cent); surgeons' websites (55.6 per cent); pictures, diagrams or photos (42.6 per cent); videos (37.0 per cent); and social media (10.2 per cent).

CONCLUSION

At least 46.9 per cent of patients undergoing elective ear surgery use online resources. Most time is spent using written information, pictures, diagrams, photos and videos. Therefore, it is increasingly essential that accurate and informative resources in these formats are readily available online.

Evaluation of the Panbio™ COVID-19 IgG rapid test device performance

Background

The Panbio™ COVID-19 IgG Rapid Test Device ("Panbio™") detects IgG antibodies against the SARS-CoV-2 spike protein from viral infection or vaccination.

Objectives

To determine the diagnostic sensitivity and specificity of the Panbio™ professional use test, using fingerstick whole blood and venous plasma.

Study design

Fingerstick whole blood and venous plasma from each participant were tested with Panbio™ and compared against the SARS-CoV-2 IgG II assay on the Abbott Architect™ platform (Europe) or the equivalent AdviseDx SARS-CoV-2 IgG II Abbott Alinity i™ platform (US). 447 evaluable participants were enrolled across 6 US and 9 European clinical centers.

Results

For unvaccinated participants with PCR-confirmed infection ≥21 days post-symptom onset, the Panbio™ sensitivity with fingerstick whole blood was 92.6 % (95 % CI: 85.9, 96.7), and the specificity was 97.0 % (95 % CI: 93.1, 99.0). For venous plasma, the sensitivity was 90.0 % (95 % CI: 79.5, 96.2) for participants with PCR-confirmed infection and symptom onset 22-180 days ago; the specificity was 96.3 % (92.2, 98.6). For vaccinated participants, the sensitivity was 98.4 % (95 % CI: 91.2, 100.0) for fingerstick whole blood and 96.7 % (95 % CI: 88.7, 99.6) for venous plasma.

Conclusion

The Panbio™ test had high sensitivity and specificity for detecting IgG against the SARS-CoV-2 spike protein.

Attitudes and barriers to participation in window-of-opportunity trials reported by White and Asian/Asian British ethnicity patients who have undergone treatment for endometrial cancer

PURPOSE

Window-of-opportunity trials (WOT) are a study design that have been used to investigate drug activity in endometrial cancer (EC). Recruitment to cancer clinical trials by patients from ethnic minority groups is reported to be lower than for patients of White ethnicity.

METHODS

A verbal questionnaire was conducted with White and Asian/Asian British ethnicity patients who had undergone treatment for EC. Strategic purposeful sampling was used to recruit patients from diverse social/educational backgrounds. Questions explored: background knowledge of clinical research, WOT study design, and views on medications that might be investigated. Thematic analysis was used to explore motivations for WOT participation and perceived barriers.

RESULTS

In total, 21 patients were recruited to the study (15 White and 6 Asian/Asian British). Views on optimum time to receive trial information differed, preferences ranging from 'at the time of diagnosis' to 'a few days after diagnosis'. The choice of medication under investigation had a strong influence on potential willingness to participate, with greater interest reported in medications derived from vitamins or food supplements rather than hormone-based drugs. Potential barriers to participation included concern over potential side-effects and the emotional/physical burden of a cancer diagnosis prior to major surgery.

DISCUSSION

This study provides important insights into patients' views on WOT participation in EC and raises issues that need to be considered for future trial design and participant recruitment materials. The timing and format of study information and type of substance under investigation were factors influencing potential participation. Future studies should consider using multi-lingual visual information videos to address information needs, as this may encourage participation by ethnic minority patients.

Light-up split aptamers: binding thermodynamics and kinetics for sensing

Due to their programmable structures, many aptamers can be readily split into two halves while still retaining their target binding function. While split aptamers are prevalent in the biosensor field, fundamental studies of their binding are still lacking. In this work, we took advantage of the fluorescence enhancement property of a new aptamer named OTC5 that can bind to tetracycline antibiotics to compare various split aptamers with the full-length aptamer. The split aptamers were designed to have different stem lengths. Longer stem length aptamers showed similar dissociation constants (Kd) to the full-length aptamer, while a shorter stem construct showed an 85-fold increase in Kd. Temperature-dependent fluorescence measurements confirmed the lower thermostability of split aptamers. Isothermal titration calorimetry indicated that split aptamer binding can release more heat but have an even larger entropy loss. Finally, a colorimetric biosensor using gold nanoparticles was designed by pre-assembling two thiolated aptamer halves, which can then link gold nanoparticles to give a red-to-blue color change.

Intracorporeal or extracorporeal anastomosis after minimally invasive right colectomy: a systematic review and meta-analysis

PURPOSE

As part of the wide adoption of minimally invasive surgery, intracorporeal anastomosis is becoming increasingly common. The benefits of minimally invasive versus open right colectomy are well known although the additional benefits of an intracorporeal anastomosis, performed laparoscopically or robotically, are unclear. The aim of this study was to assess the current literature comparing intracorporeal and extracorporeal anastomosis in the setting of laparoscopic and robotic-assisted right colectomy.

METHODS

A systematic review and meta-analysis was conducted according to PRISMA and AMSTAR methods. Studies included were randomized controlled trials and prospective or retrospective cohort studies, between January 1 2010 and July 1 2021, comparing intracorporeal and extracorporeal anastomosis with laparoscopic and robotic approaches. Four groups were identified: laparoscopic extracorporeal anastomosis (L-ECA), laparoscopic intracorporeal anastomosis (L-ICA), robotic extracorporeal anastomosis (R-ECA), and robotic intracorporeal anastomosis (R-ICA). Operative time, rate of conversion to an open procedure, surgical site infection, reoperation within 30 days, postoperative complications within 30 days, and length of hospital stay were assessed.

RESULTS

Twenty-one retrospective cohort studies were included in the final analysis. R-ICA and R-ECA had comparable operative times, but a robotic approach required more time than laparoscopic (68 min longer, p < 0.00001). Conversion to open surgery was 55% less likely in the R-ICA group vs. L-ICA, and up to 94% less likely in the R-ICA group in comparison to the R-ECA group. Length of hospital stay was shorter for R-ICA by a half day vs. R-ECA, and up to 1 day less vs. L-ECA. There were no differences in postoperative complications, reoperations, or surgical site infections, regardless of approach. However, the included studies all had high risks of bias due to confounding variables and patient selection.

CONCLUSION

Robotic-assisted right colectomy with intracorporeal anastomosis was associated with shorter length of hospitalization and decreased rate of conversion to open surgery, compared to either laparoscopic or extracorporeal robotic approaches. Prospective studies are needed to better understand the true impact of robotic approach and intracorporeal anastomosis in right colectomy.

Three Decade Single-Institution Experience of Safety and Efficacy of Radiotherapy and Adjuvant Chemotherapy for Young Adult Patients with Medulloblastoma

PURPOSE/OBJECTIVE(S)

The rarity of medulloblastoma in the adult population limits information on optimal treatment and clinical outcomes. Adjuvant chemoradiation has been correlated to improved overall survival (OS) in a recent National Cancer Database (NCDB) analysis. We performed a retrospective safety and efficacy analysis of radiation (RT) +/- adjuvant chemotherapy (aCTH) in young adult patients with medulloblastoma to better understand outcomes, prognostic factors, and possibly optimal treatment strategies.

MATERIALS/METHODS

We conducted an IRB-approved retrospective chart review on young adult (age ≥18 - 39 years old) patients with medulloblastoma treated at our institution (1992-2018) with a minimum follow-up of 6 months from completion of therapy. We gathered data on patient and disease characteristics, treatment, and clinical outcomes, including OS, progression-free survival (PFS), local control (LC), and freedom from distant metastasis (FDM). We employed Cox regression model for univariable and multivariable analyses and Kaplan-Meier (KM) test methods for survival analyses, using JMP version 15.0 software.

RESULTS

Thirty-one patients were treated with postoperative RT including craniospinal irradiation (median dose: 2340 cGy/13 fractions) followed by tumor bed/posterior fossa (median total dose: 5580 cGy/31 fractions) either alone (n = 9; 29%) or with adjuvant chemotherapy (aCTH: n = 22; 71%); mostly as per COG A9961 Regimen A: oral lomustine, intravenous cisplatin, and intravenous vincristine (n = 12). 54.6% (n = 12) were known to complete the full aCTH course. Common RT acute toxicities included G1-2 nausea and/or vomiting (N/V; n = 8) and G1-2 fatigue (n = 6). Common aCTH acute toxicities included G1-2 N/V (n = 7) and peripheral neuropathy: G1-2 (n = 6) and G3 (n = 3). Late adverse events were primarily G1-2 peripheral neuropathy and gait imbalance (22.6%), G1-2 hormonal disturbances (19.4%) and G1-2 neurocognitive impairment (16.1%). Male patients had worse OS, PFS, FDM, and LC. Age at diagnosis, tumor location (lateral vs. central), and completion of aCTH course were shown on uni- and multi-variable analysis to be significantly associated with OS; p<0.05. KM survival analysis revealed superior 10-year PFS and OS in patients who completed aCTH compared to those who received RT alone or did not complete aCTH: 72.9% vs 59.3% vs 42%, p = 0.461, and 74.1% vs 63.5% vs 40%, p = 0.033, respectively. A similar trend was noted for LC and FDM.

CONCLUSION

Our series provides a report of acute and late side effects of treatment of young adult patients with medulloblastoma. Significant OS and PFS advantage are seen of aCTH completion in this patient population. Since optimal treatment of these patients is still an unmet need, prospective studies for this rare disease entity are needed.

Concern for Increased Prevalence of Heyde's Syndrome in Patients on Hemodialysis

The association between aortic stenosis and increased gastrointestinal arteriovenous malformations is known as Heyde's syndrome. An acquired von Willebrand deficiency mediates the connection between these two seemingly dispersed pathologies. As von Willebrand factor passes through a stenosed aorta, it is broken down and can no longer inhibit angiogenesis, leading to angiodysplasias. Heyde's syndrome can manifest with chronic, refractory anemia requiring multiple hospitalizations for symptomatic gastrointestinal bleeding and transfusion. Hitherto, Heyde's syndrome has been considered exceptionally rare, with 1-3% of populations with aortic stenosis. However, given that 31.7% of patients with gastrointestinal angioplasty have aortic stenosis and gastrointestinal arteriovenous malformations are not screened for in patients without anemia, the prevalence of Heyde's syndrome is most likely higher than currently reflected in the literature. Also, the prevalence of Heyde's syndrome in populations who are predisposed to angiodysplasias, such as those on hemodialysis, is understudied. We aim to impart a need for increased research on the prevalence of Heyde's syndrome, especially in high-risk patients. This case report presents a patient with severe Heyde's syndrome on hemodialysis, showing an unconsidered risk factor for Heyde's syndrome in need of further research.

First Double-Differential Measurement of Kinematic Imbalance in Neutrino Interactions with the MicroBooNE Detector

We report the first measurement of flux-integrated double-differential quasielasticlike neutrino-argon cross sections, which have been made using the Booster Neutrino Beam and the MicroBooNE detector at Fermi National Accelerator Laboratory. The data are presented as a function of kinematic imbalance variables which are sensitive to nuclear ground-state distributions and hadronic reinteraction processes. We find that the measured cross sections in different phase-space regions are sensitive to different nuclear effects. Therefore, they enable the impact of specific nuclear effects on the neutrino-nucleus interaction to be isolated more completely than was possible using previous single-differential cross section measurements. Our results provide precision data to help test and improve neutrino-nucleus interaction models. They further support ongoing neutrino-oscillation studies by establishing phase-space regions where precise reaction modeling has already been achieved.

3D-QSAR-based design, synthesis and biological evaluation of 2,4-disubstituted quinoline derivatives as antimalarial agents

2,4-Disubstituted quinoline derivatives were designed based on a 3D-QSAR study, synthesized and evaluated for antimalarial activity. A large dataset of 178 quinoline derivatives was used to perform a 3D-QSAR study using CoMFA and CoMSIA models. PLS analysis provided statistically validated results for CoMFA (r2ncv = 0.969, q2 = 0.677, r2cv = 0.682) and CoMSIA (r2ncv = 0.962, q2 = 0.741, r2cv = 0.683) models. Two series of a total of 40 2,4-disubstituted quinoline derivatives were designed with amide (quinoline-4-carboxamide) and secondary amine (4-aminoquinoline) linkers at the -C4 position of the quinoline ring. For the purpose of selecting better compounds for synthesis with good pEC50 values, activity prediction was carried out using CoMFA and CoMSIA models. Finally, a total of 10 2,4-disubstituted quinoline derivatives were synthesized, and screened for their antimalarial activity based on the reduction of parasitaemia. Compound #5 with amide linker and compound #19 with secondary amine linkers at the -C4 position of the quinoline ring showed maximum reductions of 64% and 57%, respectively, in the level of parasitaemia. In vivo screening assay confirmed and validated the findings of the 3D-QSAR study for the design of quinoline derivatives.

First Measurement of Quasielastic Λ Baryon Production in Muon Antineutrino Interactions in the MicroBooNE Detector

We present the first measurement of the cross section of Cabibbo-suppressed Λ baryon production, using data collected with the MicroBooNE detector when exposed to the neutrinos from the main injector beam at the Fermi National Accelerator Laboratory. The data analyzed correspond to 2.2×10^{20} protons on target running in neutrino mode, and 4.9×10^{20} protons on target running in anti-neutrino mode. An automated selection is combined with hand scanning, with the former identifying five candidate Λ production events when the signal was unblinded, consistent with the GENIE prediction of 5.3±1.1 events. Several scanners were employed, selecting between three and five events, compared with a prediction from a blinded Monte Carlo simulation study of 3.7±1.0 events. Restricting the phase space to only include Λ baryons that decay above MicroBooNE's detection thresholds, we obtain a flux averaged cross section of 2.0_{-1.7}^{+2.2}×10^{-40}  cm^{2}/Ar, where statistical and systematic uncertainties are combined.