Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Medium-Term Weight Loss and Remission of Comorbidities Following Endoscopic Sleeve Gastroplasty: a Systematic Review and Meta-analysis

This systematic review and meta-analysis aimed to determine the short- and medium-term weight loss outcomes and comorbidity resolution following endoscopic sleeve gastroplasty. Our search identified 35 relevant studies containing data from 7525 patients. Overall, pooled short-term (12 months) total weight loss (TWL) was 16.2% (95% CI 13.1-19.4%) in 23 studies (n = 5659). Pooled medium-term TWL was 15.4% (95% CI 13.7-17.2%) in 10 studies (n = 4040). Diabetes resolution was 55.4% (95% CI 46-64%), hypertension resolution was 62.8% (95% CI 43-82%), dyslipidaemia resolution was 56.3% (95% CI 49-63%), and obstructive sleep apnoea resolution was 51.7% (95% CI 16.2-87.3%) in four studies (n = 480). This pooled analysis demonstrates that ESG can induce durable weight loss and resolution of obesity-associated comorbidities in patients with moderate obesity.

Long-term efficacy of total versus posterior partial fundoplication in patients with gastro-oesophageal reflux disease: a systematic review and meta-analysis

INTRODUCTION

Laparoscopic fundoplication remains the standard treatment for patients with severe gastro-oesophageal reflux disease (GORD). Multiple randomised controlled trials (RCTs) have compared the two most commonly performed surgical techniques, total and posterior partial fundoplication (Nissen [NF] and Toupet [TF]), in terms of symptom control and treatment failure in patients without subsequent dysmotility disorders. We aimed to conduct a systematic review and meta-analysis of these two techniques with regard to the long-term effect on reflux control and associated dysphagia.

METHODS

The MEDLINE®, Embase®, PubMed® and Cochrane Library databases were searched, and all the relevant published RCTs were shortlisted according to the inclusion criteria. The summated outcomes of long-term results relating to the recurrence of GORD and dysphagia were evaluated in a meta-analysis using RevMan software.

RESULTS

Eight studies (all RCTs) on 1,545 patients undergoing NF or TF were eligible for inclusion in this meta-analysis. There were 799 patients in the NF group and 746 in the TF group. In the random effects model analysis, the incidence of long-term recurrence of GORD was not statistically different between the NF and TF cohorts (odds ratio [OR]: 0.69, 95% confidence interval [CI]: 0.34-1.41, z=1.01, p=0.31). However, the incidence of long-term dysphagia was statistically lower in the TF group (OR: 2.92, 95% CI: 1.49-5.72, z=3.13, p=0.002) with low between-study heterogeneity (I2=0%).

CONCLUSIONS

The findings of this systematic review and meta-analysis on symptomatic GORD appear to be in favour of partial posterior fundoplication (TF) as the optimal treatment. It provides equivalent outcomes in reflux symptom control with a lower risk of postoperative dysphagia compared with total fundoplication (NF).

Interventions for Grieving and Bereaved Informal Caregivers: A Scoping Review of the Canadian Literature

Background: The palliative approach to care is playing a larger role in the healthcare of older adults in Canada. Within (hospice) palliative care, informal caregivers play a crucial role as part of the interdisciplinary care team. Ensuring high quality palliative care includes providing effective grief and bereavement supports for them. Objective: This study aimed to identify current interventions addressing the grief and bereavement experiences of informal caregivers of geriatric patients in the Canadian (hospice) palliative/end-of-life care realm. Methods: A scoping review was undertaken using Arksey and O'Malley's framework. Seven electronic health and social science databases were searched. In addition, several stakeholder organizations' websites were reviewed to identify grey literature sources. Interventions that took place in Canada, were in English, and explored grief and bereavement supports for informal caregivers in an adult/geriatric (hospice) palliative care setting were included. After full text review, data were extracted and charted. Major themes were established following thematic content analysis. Results: Within a total of 18 sources, three themes were identified: (1) Classification of intervention, (2) Format of intervention, and (3) Intervention target. Method of delivery and type of intervention for grief and bereavement supports were aligned with the international literature. There is a need for large-scale evaluations of interventions and informal caregivers should be engaged in this process. Practitioners should be encouraged to direct bereavement interventions toward grieving caregivers, and to collaborate with them to improve access to these interventions. Policy makers should provide additional funding for grief interventions for informal caregivers. Conclusions: It is important to better understand the needs of informal caregivers experiencing grief and bereavement. Interdisciplinary collaborations will be necessary to develop, evaluate, and scale future interventions.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Support for Informal Caregivers in Canada: A Scoping Review from a Hospice and Palliative/End-of-Life Care Lens

Objective: Informal caregivers (ICs) providing care for those at the end-of-life face physical, psycho-social, emotional, and/or financial challenges. However, there is a paucity of research towards the effectiveness of available interventions for this vulnerable population. The purpose of this scoping review was to investigate the availability and efficacy of interventions for ICs providing hospice and palliative/end-of-life care in Canada. Methods: Using Arksey and O’Malley's five step framework, a scoping review was conducted in the spring of 2020. Key electronic healthcare, social sciences, and grey literature databases were searched. Relevant publications from 2005 to 2019 were screened for inclusion criteria, and a thematic content analysis was conducted to summarize all key findings. Results: Initial searches yielded 145 results out of which 114 distinct articles were obtained. De-duplication and final screening yielded 28 sources which met inclusion criteria (22 peer-reviewed articles [78%] and 6 grey sources [22%]; 12 qualitative papers [42%]). Through thematic content analysis, four major themes were identified: [1] Direct financial support, [2] Direct psycho-sociospiritual support, [3] Indirect patient information provision/education, and [4] Indirect patient support. Conclusions: Healthcare practitioners should provide information on patient care and financial aid to ICs. Policies should aim to expand eligibility for and access to financial aid, in particular the Compassionate Care Benefits (CCB). Future research should focus on exploring other interventions, such as physical activities, to better support this vulnerable population. The results from this review will help inform and improve the well-being of ICs providing end-of-life care in Canada and beyond.

The Grief and Bereavement Experiences of Informal Caregivers: A Scoping Review of the North American Literature

Background: Informal caregivers are a significant part of the hospice and palliative care landscape as members of the interdisciplinary care team. Despite this, little is known about the impact this responsibility has on informal caregivers’ experiences of grief and bereavement. Objective: To address this, a scoping review of the literature was conducted to explore the current state of knowledge toward grief and bereavement of informal caregivers of adult/geriatric patients in the hospice and palliative/end-of-life care realm within North America. Methods: Using Arksey and O’Malley's 5-step framework, key electronic health care and social sciences databases (eg, CINAHL, MEDLINE, ProQuest Sociological Abstracts, PsycINFO) alongside gray literature sources were searched and screened against inclusion and exclusion criteria. A thematic content analysis was used to identify key themes. Results: 29 articles met the final inclusion criteria with 3 central themes emerging: (1) mediators of grief, (2) grief experiences, and (3) types of grief. Discussion: Informal caregivers encounter unique grief and bereavement experiences: The range of psychosocial outcomes, both negative and positive, can be affected by various mediators such as caregiver burden, demographics, disease type of the patient being cared for, etc. Bereavement interventions must be designed with the mediators of grief in mind. Conclusions: Understanding the nuances of informal caregivers’ experiences with grief and bereavement will inform and advance practice, policy, and research. Practitioners/clinicians should be further educated on how to properly acknowledge the complexity of grief and bereavement for informal caregivers, specifically paying attention to mediators. Further research needs to consider the role of culture.

SP2.2.4National multi centre cohort study of transferable skills acquired among redeployed core surgical trainees to intensive care units during the COVID-19 pandemic

Aim

Due to the COVID-19 pandemic a large number of core surgical trainees have been redeployed to intensive care units across the country. This study analyses the procurement of transferable skills by trainees mapped to the ISCP curriculum among a large national cohort.

Methods

An anonymous questionnaire mapped to common areas in the ISCP syllabus, including basic sciences, post-operative care, critical care and management of the dying patient, was administered to a nationwide group of core surgical trainees redeployed to ITU. The results were compared with responses from a cohort of trainees that were not redeployed. Subgroup analysis was also performed on the redeployed cohort to compare skills before and after redeployment.

Result

A total of 72 complete responses from among 3 deaneries nationwide were received, 39 who were redeployed, and 33 who were not. Mean age (24.5 vs 24.9 years) and time post-graduation (37.5 vs 38.2 months) were similar in each group. The average length of redeployment was 12 ±0.157 weeks. The mean score in those not redeployed was 1.85 ±0.167, compared to 4.02±0.175 in the redeployed cohort (p < 0.05). Among those redeployed, scores prior to redeployment were significantly lower 1.89 ±0.122 (p < 0.05).

Conclusion

This study demonstrates that even a brief period of intensive care experience significantly increases knowledge of key aspects of the ISCP curriculum. It is the authors’ opinion that a module of intensive care experience during core surgical training should be considered. Our cohort will be followed to assess performance in postgraduate examinations.

EP.WE.829Does Covid-19 increase the risk of gastrointestinal perforation? A preliminary UK-based multicentre cohort study

Aims

Recent case reports have described occult gastrointestinal perforation secondary to Covid-related microcirculatory thromboembolic phenomena. This study aims to evaluate the effect of Covid-19 on the incidence of gastrointestinal perforations across South West London (SWL).

Methods

A retrospective cohort study included all patients with gastrointestinal perforations presenting to three SWL-based NHS hospitals from 01/04/2020-31/12/2020 (i.e. “pandemic” cohort; from the first national lockdown), versus a representative “pre-pandemic” cohort (01/04/2019-31/12/2019). Data was extracted from the hospital coding records, patient case-notes, and the NELA database, and analysed by two independent clinicians.

Results

A total of 448 patients were included. 9.3% more (214 vs. 234, p = 0.286) gastrointestinal perforations presented during the pandemic period than beforehand. Comparing both periods, there were no significant differences between the numbers of colonic diverticular perforations (183 vs. 185), gastrojejunal ulcer perforations (1 per period), and terminal ileal perforations (1 per period). There were 78% more peptic ulcer perforations (9 vs. 16) and 55% more gallbladder perforations (20 vs. 31) during the pandemic period, although no overall significant difference was derived at the 95% confidence interval (Χ2=3.458, p = 0.484).

Conclusions

While there was no significant overall increase in spontaneous gastrointestinal perforation during Covid-19, this study clearly suggests increased rates of peptic and gallbladder perforations. Larger-scale epidemiological data are warranted to ascertain whether this is secondary to increased consumption of alcohol, non-steroidal anti-inflammatory medication or other pro-ulcerative drug regimes during the pandemic. Further data will also be vital to highlight delays in investigation and/or presentation resulting in these increased perforation rates.

SP4.1.3 The effect of the Covid-19 pandemic on case selection and perioperative outcomes of emergency laparotomies: a UK-based multicentre cohort study

Aims

Evaluating the effect of Covid-19 on case selection and perioperative outcomes of emergency laparotomies across South West London (SWL).

Methods

A retrospective cohort study including all emergency laparotomies performed at three SWL-based NHS hospitals from 01/04/2020-31/12/2020 (i.e., “pandemic” cohort; from the first national lockdown), versus a “pre-pandemic” cohort (01/04/2019-31/12/2019). Data was extracted from the NELA database and hospital records, and analysed by two independent clinicians.

Results

414 patients met the inclusion criteria. 17.6% fewer (227 vs. 187) laparotomies were performed during the pandemic period. There were no significant sociodemographic differences between cohorts (mean age 64.5 vs. 62.7 years, p = 0.284; M:F ratio 1:1.154 vs. 1:0.928, p = 0.221). Pre-operative NELA risk scores were higher before the pandemic (mean 13.05% vs. 9.55%, p = 0.020). The commonest indication for laparotomy in both cohorts was small bowel obstruction (32.6% vs. 37.4%), treated most commonly with adhesiolysis. Postoperatively, fewer patients received HDU/ITU care during the pandemic than before (ward-based recovery 4.7% vs. 13.8%, HDU/ITU recovery 93.4% vs. 79.4%, χ²=15.4, p < 0.005). Mean duration of ITU stay was significantly shorter during the pandemic (4.5 vs. 2.7 days, p < 0.005), as was total length of inpatient stay (20.2 vs. 14.3 days, p = 0.0156).

Conclusions

The overall reduction in emergency laparotomies observed during the pandemic period was potentially secondary to tighter case selection guided by objective risk stratification. Fewer patients were recovered postoperatively on HDU/ITU, and patients were generally discharged from hospital earlier. Such trends in perioperative care served to support organizational prioritization in response to Covid-19 service provision.

499 Upper GI Surgical Clinic Referrals, Can We Improve Patient Experience?

Introduction

With increasing pressure on NHS to deal with long waiting lists, solutions to reduce waiting times are imperative. In the era of the COVID-19 pandemic, we need to reshape the way we look into Outpatient clinic appointments.

Aim

To review all clinic referrals to UGI surgical clinic and highlight any potential pathways that can improve waiting times and patient experience.

Method

Patients referred to UGI clinic over 2 months were collected from Iclip, EPR and EDM. Post-discharge appointments and DNA’s were excluded. Data collected included time from referral to clinic, type of referral, symptoms, investigations, potential pathway, first clinic outcome, and appropriateness of referral.

Results

Total of 147 referrals analyzed. Time from referral to clinic appointment is 51 days. GP referrals represented 73% while the rest from consultant colleagues. The most common symptoms were biliary colic and GORD. OGD and PH manometry were the most common investigations requested. The most common first outcome was pre investigate and clinic follow up. Two potential pathways identified are Biliary colic and GORD pathway. 90% of referrals were appropriate.

Conclusions

Biliary colic pathway and GORD pathway are 2 potential pathways that can cut off waiting times for clinic appointments and improve patient experience in outpatient clinics.

Informal Caregiving for People With Life-Limiting Illness: Exploring the Knowledge Gaps

Background: People with life-limiting illness are increasingly having more care provided to them by informal caregivers (ICs) such as family members and friends. Although there is a substantial amount of literature surrounding informal caregiving, there is a paucity of research from a hospice palliative care angle. To address this knowledge gap, this scoping review explored the effects of/challenges to informal caregiving at the end of life in Canada. Methods: Scoping review of the literature following Arksey and O’Malley’s framework. Key healthcare and social sciences databases alongside the gray literature were searched. Relevant scholarly and gray literature sources from 2005 to 2019 were screened for inclusion criteria, and a thematic content analysis employed to summarize findings. Results: Of 2,717 initial search results, 257 distinct full text articles were obtained. Following deduplication and screening, 33 met inclusion criteria. Four major themes were identified: (1) Physical health challenges, (2) Psycho-socio-spiritual health challenges, (3) Financial issues, and (4) Health system issues. Gender of ICs was also found to be an important contributor to the differing effects of providing support. Conclusions: This review raises awareness toward ICs regarding the numerous physical, psycho-socio-spiritual, financial, and health system challenges faced during care for people with life-limiting illness. The knowledge gained will inform and advance future practice, policy, and research. Application to interventions (such as caregiver benefits) will assist to improve informal caregiving experiences and outcomes alongside quality of life. Further research is required to understand these unique experiences and the challenges of minority IC populations.

Time of Transfer of Admitted Patients from the ED: A Contributor to ED Boarding in High-Volume Community Hospitals

The twin challenges of bed boarding and "hallway medicine" have emerged in recent years as key healthcare issues. Many hospitals, challenged with increasing demand and limited resources, have tried to find efficiencies within their operations. One such strategy is that of early morning discharges and expedited bed turnaround times. We conducted a retrospective study within three high-volume hospitals in the Greater Toronto Area looking at discharge times of in-patients and transfer times of admitted, Emergency Department (ED)-boarded patients. We discovered a consistent pattern of late-in-the-day discharges, and even later-in-the-day transfers of boarded ED patients, indicating that this may be a potential source of increased efficiency for overburdened hospitals.

Abstract P3-08-13: Exploring the role of ctDNA in triple negative breast cancer

BACKGROUND: Previously published work shows that triple negative (TNBC) is a heterogeneous disease with varying levels of genomic instability, where higher genomic instability is associated with poorer prognosis. Subgroups of TNBC patients with distinct patterns of genome aberrations may indicate pathologies in specific genome maintenance/repair processes. Circulating tumor DNA (ctDNA) as assessed by next generation sequencing (NGS) is a relatively non-invasive test that may provide prognostic and predictive information.

AIM OF STUDY: To analyze genomic alterations with serial plasma samples using NGS methods of ctDNA analysis and determine the utility for actionability and disease burden monitoring. We shall also determine whether TNBC subgroups differ in their ctDNA profiles. Shallow whole genome sequencing vs targeted capture at depth will be contrasted to determine sensitivity for relapse detection.

METHODS: Enrollment of a planned cohort of TNBC patients (N=300) with any stage, at diagnosis (dx) or within 2 years of dx, or at relapse of disease with ongoing plasma sampling every 3 -6 months. Patient age, stage, grade, type of chemotherapy, date of relapse and date of last followup are collected. Tumor tissue (FFPE), saliva for germline mutations and serial blood draws for ctDNA are analyzed with two NGS sequencing methods: (i) a high sensitivity small hotspot gene panel (33 genes, 170 hotspots), directed purely at actionable findings (ii) capture sequencing directed at multiple regions of the genome or shallow whole genome sequencing.

RESULTS: Preliminary analysis in 20 patient cases using the targeted hotspot panel. . Median followup 151 days. Two cases had plasma drawn at time of relapsed disease and 1 at the time of de novo metastatic disease; 12 had plasma samples drawn prior to neoadjuvant chemotherapy (clinical T1/T2N1, T3/T4Nany), and 5 had plasma draws after primary surgery (pathologic T1N0, T2N0). Of the neoadjuvant cases, 5 (42%) had a pathologic complete response (pCR); 4 with ctDNA mutations and 1 without. Six (58%) neoadjuvant cases did not achieve a pCR; 3 with ctDNA mutations, 3 without. One patient is awaiting surgery. Twelve (60%) cases had mutations in TP53, one case had 2 different TP53 mutations (no pCR) and one case had 3 mutations: TP53, PIK3CA, KRAS (achieved pCR). Of the cases treated with curative intent, with short followup (FU), there have been no relapses including the case of the sample containing 3 mutations.

CONCLUSION: TP53 mutations may be a marker of higher genomic alteration burden and may have prognostic value in patients with newly diagnosed, non-metastatic TNBC with longer FU. Ongoing analysis of serial plasma samples and FFPE analysis may provide further insight into the prognostic value of ctDNA. Full genome sequencing may be needed identify other mutations that have prognostic and/or predictive value. We have accrued over 200 patients with samples being analyzed and plan to present an interim analysis of the cohort at SABCS 2018.

Citation Format: den Brok WD, Kong E, Bates C, Aguirre-Hernandez R, Miller RR, Lum A, Wan A, Shah S, Aparicio S, Gelmon KA. Exploring the role of ctDNA in triple negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-08-13.

Characterization of Simultaneous Pressure Waves as Biomarkers for Colonic Motility Assessed by High-Resolution Colonic Manometry

Simultaneous pressure waves (SPWs) in manometry recordings of the human colon have been associated with gas expulsion. Our hypothesis was that the SPW might be a critical component of most colonic motor functions, and hence might act as a biomarker for healthy colon motility. To that end, we performed high-resolution colonic manometry (HRCM), for the first time using an 84-sensor (1 cm spaced) water-perfused catheter, in 17 healthy volunteers. Intraluminal pressure patterns were recorded during baseline, proximal and rectal balloon distention, after a meal and following proximal and rectal luminal bisacodyl administration. Quantification was performed using software, based on Image J, developed during this study. Gas expulsion was always associated with SPWs, furthermore, SPWs were associated with water or balloon expulsion. SPWs were prominently emerging at the termination of proximal high amplitude propagating pressure waves (HAPWs); we termed this motor pattern HAPW-SPWs; hence, SPWs were often not a pan-colonic event. SPWs and HAPW-SPWs were observed at baseline with SPW amplitudes of 12.0 ± 8.5 mmHg and 20.2 ± 7.2 mmHg respectively. The SPW occurrence and amplitude significantly increased in response to meal, balloon distention and luminal bisacodyl, associated with 50.3% anal sphincter relaxation at baseline, which significantly increased to 59.0% after a meal, and 69.1% after bisacodyl. Often, full relaxation was achieved. The SPWs associated with gas expulsion had a significantly higher amplitude compared to SPWs without gas expulsion. SPWs could be seen to consist of clusters of high frequency pressure waves, likely associated with a cluster of fast propagating, circular muscle contractions. SPWs were occasionally observed in a highly rhythmic pattern at 1.8 ± 1.2 cycles/min. Unlike HAPWs, the SPWs did not obliterate haustral boundaries thereby explaining how gas can be expelled while solid content can remain restrained by the haustral boundaries. In conclusion, the SPW may become a biomarker for normal gas transit, the gastrocolonic reflex and extrinsic neural reflexes. The SPW assessment reveals coordination of activities in the colon, rectum and anal sphincters. SPWs may become of diagnostic value in patients with colonic dysmotility.

An unusual diaphragmatic hernia with gastric perforation and sub-acute presentation

Gastric perforation into the thoracic cavity through a diaphragmatic hernia is rare but, when it occurs, patients present in severe distress, with mortality approaching 50%. We present a unique case in which a fibrotic reaction between the stomach and the parietal pleura led to a subacute presentation upon perforation. The extra time that this afforded led to more effective multidisciplinary team management and ultimately an excellent outcome for the patient.

Laparoscopic repair of a spontaneous diaphragmatic hernia

BACKGROUND

Spontaneous diaphragmatic hernia without a previously documented history of trauma is uncommon and clinical presentation can often be atypical ranging from an incidental radiological finding to patients presenting with complications.

CASE PRESENTATION

In this video we present the case of a patient presenting with gastric perforation within a large spontaneous diaphragmatic hernia in the central part of the left hemidiaphragm.

CONCLUSIONS

Management of a complicated diaphragmatic hernia could be achieved using laparoscopic approach. The rarity of these hernias means that the operative strategy necessary for safe dissection and repair has to be individualized for each patient.

Demonstration of High Performance in Layered Deuterium-Tritium Capsule Implosions in Uranium Hohlraums at the National Ignition Facility

We report on the first layered deuterium-tritium (DT) capsule implosions indirectly driven by a "high-foot" laser pulse that were fielded in depleted uranium hohlraums at the National Ignition Facility. Recently, high-foot implosions have demonstrated improved resistance to ablation-front Rayleigh-Taylor instability induced mixing of ablator material into the DT hot spot [Hurricane et al., Nature (London) 506, 343 (2014)]. Uranium hohlraums provide a higher albedo and thus an increased drive equivalent to an additional 25 TW laser power at the peak of the drive compared to standard gold hohlraums leading to higher implosion velocity. Additionally, we observe an improved hot-spot shape closer to round which indicates enhanced drive from the waist. In contrast to findings in the National Ignition Campaign, now all of our highest performing experiments have been done in uranium hohlraums and achieved total yields approaching 10^{16} neutrons where more than 50% of the yield was due to additional heating of alpha particles stopping in the DT fuel.

Laparo-endoscopic combined approach for excision of gastrointestinal stromal tumour close to the oesophagogastric junction

Tumours close to the oesophagogastric junction (OGJ) are difficult to excise due to high risk of complications. Laparoscopic and endoscopic combined surgery allows minimally invasive access while increasing tumour visualization. Computed tomography (CT) scanning of a 68-year-old female demonstrated a lesion suspicious of a gastrointestinal stromal tumour located 2 cm from the OGJ on the posterior gastric wall. Stapled excision was performed intragastrically and followed by endoscopic removal. Gastroscopy 7 months post-op and follow-up CT scan at 5 years demonstrated no recurrence of the primary tumour and no new disease. Laparoscopic and endoscopic combined approach is a safe and effective method of removing tumours close to the OGJ.

Thin shell, high velocity inertial confinement fusion implosions on the national ignition facility

Experiments have recently been conducted at the National Ignition Facility utilizing inertial confinement fusion capsule ablators that are 175 and 165  μm in thickness, 10% and 15% thinner, respectively, than the nominal thickness capsule used throughout the high foot and most of the National Ignition Campaign. These three-shock, high-adiabat, high-foot implosions have demonstrated good performance, with higher velocity and better symmetry control at lower laser powers and energies than their nominal thickness ablator counterparts. Little to no hydrodynamic mix into the DT hot spot has been observed despite the higher velocities and reduced depth for possible instability feedthrough. Early results have shown good repeatability, with up to 1/2 the neutron yield coming from α-particle self-heating.

Introgression of leaf rust and stripe rust resistance from Sharon goatgrass (Aegilops sharonensis Eig) into bread wheat (Triticum aestivum L.)

Leaf rust and stripe rust are devastating wheat diseases, causing significant yield losses in many regions of the world. The use of resistant varieties is the most efficient way to protect wheat crops from these diseases. Sharon goatgrass (Aegilops sharonensis or AES), which is a diploid wild relative of wheat, exhibits a high frequency of leaf and stripe rust resistance. We used the resistant AES accession TH548 and induced homoeologous recombination by the ph1b allele to obtain resistant wheat recombinant lines carrying AES chromosome segments in the genetic background of the spring wheat cultivar Galil. The gametocidal effect from AES was overcome by using an "anti-gametocidal" wheat mutant. These recombinant lines were found resistant to highly virulent races of the leaf and stripe rust pathogens in Israel and the United States. Molecular DArT analysis of the different recombinant lines revealed different lengths of AES segments on wheat chromosome 6B, which indicates the location of both resistance genes.

The effects of sleeve gastectomy on gastro-esophageal reflux and gastro-esophageal motility

Sleeve gastrectomy is an increasingly performed bariatric procedure associated with low morbidity and good short to medium term effects on weight loss and comorbid conditions. Studies assessing the prevalence of post-operative gastro-esophageal reflux disease (GERD), show sleeve gastrectomy may provoke de novo GERD symptoms or worsening of pre-existing GERD. Pathophysiological mechanisms of GERD after sleeve gastrectomy include a hypotensive lower esophageal sphincter, increased gastro-esophageal pressure gradient and intra-thoracic migration of the remnant stomach. A reduction in the compliance of the gastric remnant may provoke an increase in transient lower esophageal sphincter relaxations. Time-resolved MRI suggests relative gastric stasis in the proximal remnant and increased emptying from the antrum. A lack of standardisation of technique, along with heterogeneity of studies assessing GERD may explain the wide variability in reported results. Simultaneous and careful repair of an associated hiatus hernia may result in a reduction in the prevalence of post-operative GERD.

Observation of turbulent intermittency scaling with magnetic helicity in an MHD plasma wind tunnel

The intermittency in turbulent magnetic field fluctuations has been observed to scale with the amount of magnetic helicity injected into a laboratory plasma. An unstable spheromak injected into the MHD wind tunnel of the Swarthmore Spheromak Experiment displays turbulent magnetic and plasma fluctuations as it relaxes into a Taylor state. The level of intermittency of this turbulence is determined by finding the flatness of the probability distribution function of increments for magnetic pickup coil fluctuations B˙(t). The intermittency increases with the injected helicity, but spectral indices are unaffected by this variation. While evidence is provided which supports the hypothesis that current sheets and reconnection sites are related to the generation of this intermittent signal, the true nature of the observed intermittency remains unknown.

Cancer-associated somatic DICER1 hotspot mutations cause defective miRNA processing and reverse-strand expression bias to predominantly mature 3p strands through loss of 5p strand cleavage

Our group recently described recurrent somatic mutations of the miRNA processing gene DICER1 in non-epithelial ovarian cancer. Mutations appeared to be clustered around each of four critical metal-binding residues in the RNase IIIB domain of DICER1. This domain is responsible for cleavage of the 3' end of the 5p miRNA strand of a pre-mRNA hairpin. To investigate the effects of these cancer-associated 'hotspot' mutations, we engineered mouse DICER1-deficient ES cells to express wild-type and an allelic series of the mutant DICER1 variants. Global miRNA and mRNA profiles from cells carrying the metal-binding site mutations were compared to each other and to wild-type DICER1. The miRNA and mRNA profiles generated through the expression of the hotspot mutations were virtually identical, and the DICER1 hotspot mutation-carrying cells were distinct from both wild-type and DICER1-deficient cells. Further, miRNA profiles showed that mutant DICER1 results in a dramatic loss in processing of mature 5p miRNA strands but were still able to create 3p strand miRNAs. Messenger RNA (mRNA) profile changes were consistent with the loss of 5p strand miRNAs and showed enriched expression for predicted targets of the lost 5p-derived miRNAs. We therefore conclude that cancer-associated somatic hotspot mutations of DICER1, affecting any one of four metal-binding residues in the RNase IIIB domain, are functionally equivalent with respect to miRNA processing and are hypomorphic alleles, yielding a global loss in processing of mature 5p strand miRNA. We further propose that this resulting 3p strand bias in mature miRNA expression likely underpins the oncogenic potential of these hotspot mutations.

Resident phenotypically modulated vascular smooth muscle cells in healthy human arteries

Vascular interstitial cells (VICs) are non-contractile cells with filopodia previously described in healthy blood vessels of rodents and their function remains unknown. The objective of this study was to identify VICs in human arteries and to ascertain their role. VICs were identified in the wall of human gastro-omental arteries using transmission electron microscopy. Isolated VICs showed ability to form new and elongate existing filopodia and actively change body shape. Most importantly sprouting VICs were also observed in cell dispersal. RT-PCR performed on separately collected contractile vascular smooth muscle cells (VSMCs) and VICs showed that both cell types expressed the gene for smooth muscle myosin heavy chain (SM-MHC). Immunofluorescent labelling showed that both VSMCs and VICs had similar fluorescence for SM-MHC and αSM-actin, VICs, however, had significantly lower fluorescence for smoothelin, myosin light chain kinase, h-calponin and SM22α. It was also found that VICs do not have cytoskeleton as rigid as in contractile VSMCs. VICs express number of VSMC-specific proteins and display features of phenotypically modulated VSMCs with increased migratory abilities. VICs, therefore represent resident phenotypically modulated VSMCs that are present in human arteries under normal physiological conditions.

Novel quantum dots-carboxymethyl chitosan nanocomposite nitric oxide donors capable of detecting release of nitric oxide in situ

Nitric oxide (NO) donor compounds are primarily monofunctional in that they release NO under the requisite conditions. To detect the amount and duration of NO released, subsequent analysis methods are required. It would be advantageous if a NO donor compound could both release and detect NO at the same time. This would eliminate potential errors in the analysis. In this paper, novel cadmium telluride quantum dots (CdTe QD)-carboxymethyl chitosan (CMCS) nanocomposite NO donors, including both diazeniumdiolates and fluorescence probes, were fabricated by first synthesizing CdTe QD in CMCS aqueous solution and then reacting NO as well as ethyl bromide with the resultant CdTe QD-CMCS nanocomposites. Transmission electron microscopy, scanning electron microscopy and particle size analysis were used to examine the morphology and size distribution of the CdTe QD-CMCS nanocomposite NO donors. The donors are nanospheres with CdTe QD encapsulated and have dimensions of ~300 nm. Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and contact angle tests were employed to characterize the chemical structure of the donors, and the results also show that CdTe QD are well incorporated into CMCS, and many of them are close to the surface of the donors. The precursors of the donors exhibit a fluorescent effect, and the fluorescence can be quenched by NO. The donors can release NO spontaneously in a phosphate-buffered saline solution similar to a physiological environment, and can quantitatively detect the release of NO in situ based on fluorescence quenching of the donors by the NO.

Does laparoscopic mobilisation of the stomach as part of a trans-thoracic oesophageal resection result in improved peri-operative outcomes as compared with an open approach?

A best evidence topic in surgery was written according to a structured protocol. The question addressed was whether laparoscopic mobilisation of the stomach as part of a trans-thoracic oesophageal resection results in improved peri-operative outcomes as compared with an open approach. 319 papers were found using the reported search; the 5 representing the best evidence to answer the question are discussed. The evidence on this subject is poor, none of the studies were randomised and only one was prospective. We conclude that laparoscopically-assisted gastric mobilisation during trans-thoracic oesophageal resection may have advantages over open surgery in terms of short-term peri-operative outcomes including reduced blood loss, reduced dependence on ventilatory support and shortened intensive care and overall hospital stay. However there was no difference between laparoscopic and open surgery in terms of overall morbidity or mortality rates.

Mesenteric paraganglioma with gallbladder paraganglion nest

We report on an original case of a 64 year old lady diagnosed with an extraadrenal mesenteric paraganglioma associated with an incidental histological finding of a gallbladder paraganglion. Paragangliomas are rare neuroendocrine, neural crest-derived tumours, found in diverse locations and display variable catecholamine secreting behaviour. Malignant potential can be difficult to predict on histology. We review the current literature on these multifarious tumours.

Non-alcoholic steatohepatitis mimicking liver metastasis in obesity surgery

We describe a case of non-alcoholic steatohepatitis detected incidentally during laparoscopic Roux-en-Y gastric bypass (LRYGBP). A 51-year-old female patient was scheduled for elective LRYGBP. Her weight was 144.9 kg and her body mass index was 56. Liver function tests showed mild elevation in alanine transaminase. The patient had a history of hypertension and insulin resistance and had no history of alcohol abuse. During LRYGBP, the gross appearance of the liver resembled metastatic lesions but the histology confirmed the diagnosis of non-alcoholic steatohepatitis. The appearance of the liver necessitated taking biopsies, which showed Von Meyenburg complexes and moderate macrovesicular steatosis. This patient made an uneventful recovery and was discharged 2 days postoperatively.

Expression and function of the K+ channel KCNQ genes in human arteries

BACKGROUND AND PURPOSE

KCNQ-encoded voltage-gated potassium channels (K(v) 7) have recently been identified as important anti-constrictor elements in rodent blood vessels but the role of these channels and the effects of their modulation in human arteries remain unknown. Here, we have assessed KCNQ gene expression and function in human arteries ex vivo.

EXPERIMENTAL APPROACH

Fifty arteries (41 from visceral adipose tissue, 9 mesenteric arteries) were obtained from subjects undergoing elective surgery. Quantitative RT-PCR experiments using primers specific for all known KCNQ genes and immunohistochemsitry were used to show K(v) 7 channel expression. Wire myography and single cell electrophysiology assessed the function of these channels.

KEY RESULTS

KCNQ4 was expressed in all arteries assessed, with variable contributions from KCNQ1, 3 and 5. KCNQ2 was not detected. K(v) 7 channel isoform-dependent staining was revealed in the smooth muscle layer. In functional studies, the K(v) 7 channel blockers, XE991 and linopirdine increased isometric tension and inhibited K(+) currents. In contrast, the K(v) 7.1-specific blocker chromanol 293B did not affect vascular tone. Two K(v) 7 channel activators, retigabine and acrylamide S-1, relaxed preconstricted arteries, actions reversed by XE991. K(v) 7 channel activators also suppressed spontaneous contractile activity in seven arteries, reversible by XE991.

CONCLUSIONS AND IMPLICATIONS

This is the first study to demonstrate not only the presence of KCNQ gene products in human arteries but also their contribution to vascular tone ex vivo.

LINKED ARTICLE

This article is commented on by Mani and Byron, pp. 38-41 of this issue. To view this commentary visit http://dx.doi.org/10.1111/j.1476-5381.2010.01065.x.

Ectopic pancreas, intussusception, and a ruptured mesenteric band: an unusual association

Although ectopic pancreas and intussusception are not unusual conditions, intussusception caused by ectopic pancreas is extremely rare. Its presence along with a ruptured congenital mesenteric vascular band raises the possibility of an anomaly of the vitelline vascular system. We report the case of a 26-year-old man presenting with acute abdominal pain, vomiting, and diarrhea. CT scan showed a large amount of free fluid in his abdomen and an ileo-ileal intussusception. At laparotomy he was found to have hemoperitoneum with a ruptured, actively bleeding congenital band attached to the ileal mesentery, which was ligated, with ileo-ileal intussusception that was resected. Histopathology showed ectopic pancreatic tissue as the lead point for the intussusception. It was likely to be a ruptured mesodiverticular band and along with other findings suggested a constellation of anomalies of the vitello-intestinal tract.

A fast parallel algorithm for finding the longest common sequence of multiple biosequences

BACKGROUND

Searching for the longest common sequence (LCS) of multiple biosequences is one of the most fundamental tasks in bioinformatics. In this paper, we present a parallel algorithm named FAST_LCS to speedup the computation for finding LCS.

RESULTS

A fast parallel algorithm for LCS is presented. The algorithm first constructs a novel successor table to obtain all the identical pairs and their levels. It then obtains the LCS by tracing back from the identical character pairs at the last level. Effective pruning techniques are developed to significantly reduce the computational complexity. Experimental results on gene sequences in the tigr database show that our algorithm is optimal and much more efficient than other leading LCS algorithms.

CONCLUSION

We have developed one of the fastest parallel LCS algorithms on an MPP parallel computing model. For two sequences X and Y with lengths n and m, respectively, the memory required is max{4*(n+1)+4*(m+1), L}, where L is the number of identical character pairs. The time complexity is O(L) for sequential execution, and O(|LCS(X, Y)|) for parallel execution, where |LCS(X, Y)| is the length of the LCS of X and Y. For n sequences X1, X2, ..., Xn, the time complexity is O(L) for sequential execution, and O(|LCS(X1, X2, ..., Xn)|) for parallel execution. Experimental results support our analysis by showing significant improvement of the proposed method over other leading LCS algorithms.