Efficacy and safety of a single dose of casirivimab and imdevimab for the prevention of COVID-19 over an 8-month period: a randomised, double-blind, placebo-controlled trial

BACKGROUND

There is an unmet need for COVID-19 prevention in patient populations who have not mounted or are not expected to mount an adequate immune response to complete COVID-19 vaccination. We previously reported that a single subcutaneous 1200 mg dose of the monoclonal antibody combination casirivimab and imdevimab (CAS + IMD) prevented symptomatic SARS-CoV-2 infections by 81·4% in generally healthy household contacts of SARS-CoV-2-infected individuals over a 1-month efficacy assessment period. Here we present additional results, including the 7-month follow-up period (months 2-8), providing additional insights about the potential for efficacy in pre-exposure prophylaxis settings.

METHODS

This was a randomised, double-blind, placebo-controlled trial done in the USA, Romania, and Moldova in 2020-2021, before the emergence of omicron (B.1.1.529) and omicron-lineage variants. Uninfected and unvaccinated household contacts of infected individuals, judged by the investigator to be in good health, were randomly assigned (1:1) to receive 1200 mg CAS + IMD or placebo by subcutaneous injection according to a central randomisation scheme provided by an interactive web response system; randomisation was stratified per site by the test results of a local diagnostic assay for SARS-CoV-2 and age group at baseline. COVID-19 vaccines were prohibited before randomisation, but participants were allowed to receive COVID-19 vaccination during the follow-up period. Participants who developed COVID-19 symptoms during the follow-up period underwent RT-PCR testing. Prespecified endpoints included the proportion of previously uninfected and baseline-seronegative participants (seronegative-modified full analysis set) who had RT-PCR-confirmed COVID-19 in the follow-up period (post-hoc for the timepoints of months 2-5 and 6-8 only) and underwent seroconversion (ie, became seropositive, considered a proxy for any SARS-CoV-2 infections [symptomatic and asymptomatic]; prespecified up to day 57, post-hoc for all timepoints thereafter). We also assessed the incidence of treatment-emergent adverse events. This study is registered with ClinicalTrials.gov, NCT04452318.

FINDINGS

From July 13, 2020, to Oct 4, 2021, 2317 participants who were RT-PCR-negative for SARS-CoV-2 were randomly assigned, of whom 1683 (841 assigned to CAS + IMD and 842 assigned to placebo) were seronegative at baseline. During the entirety of the 8-month study, CAS + IMD reduced the risk of COVID-19 by 81·2% (nominal p<0·0001) versus placebo (prespecified analysis). During the 7-month follow-up period, protection was greatest during months 2-5, with a 100% relative risk reduction in COVID-19 (nominal p<0·0001; post-hoc analysis). Efficacy waned during months 6-8 (post-hoc analysis). Seroconversion occurred in 38 (4·5%) of 841 participants in the CAS + IMD group and in 181 (21·5%) of 842 in the placebo group during the 8-month study (79·0% relative risk reduction vs placebo; nominal p<0·0001). Six participants in the placebo group were hospitalised due to COVID-19 versus none who received CAS + IMD. Serious treatment-emergent adverse events (including COVID-19) were reported in 24 (1·7%) of 1439 participants receiving CAS + IMD and in 23 (1·6%) of 1428 receiving placebo. Five deaths were reported, none of which were due to COVID-19 or related to the study drugs.

INTERPRETATION

CAS + IMD is not authorised in any US region as of Jan 24, 2022, because data show that CAS + IMD is not active against omicron-lineage variants. In this study, done before the emergence of omicron-lineage variants, a single subcutaneous 1200 mg dose of CAS + IMD protected against COVID-19 for up to 5 months of community exposure to susceptible strains of SARS-CoV-2 in the pre-exposure prophylaxis setting, in addition to the post-exposure prophylaxis setting that was previously shown.

FUNDING

Regeneron Pharmaceuticals, F Hoffmann-La Roche, US National Institute of Allergy and Infectious Diseases, US National Institutes of Health.

Use of a wastewater recovery product (struvite) to enhance subtropical seagrass restoration

Seagrasses are in decline worldwide, and their restoration is relatively expensive and unsuccessful compared to other coastal systems. Fertilization can improve seagrass growth in restoration but can also release nutrients and pollute the surrounding ecosystem. A slow-release fertilizer may reduce excessive nutrient discharge while still providing resources to the seagrass's rhizosphere. In this study, struvite (magnesium ammonium phosphate), a relatively insoluble, sustainable compound harvested in wastewater treatment plants, was compared to Osmocote™(14:14:14 Nitrogen: Phosphorus: Potassium, N:P:K), a popular polymer coated controlled release fertilizer commonly used in seagrass restoration. Two experiments compared the effectiveness of both fertilizers in a subtropical flow-through mesocosm setup. In the first experiment, single 0.5 mg of P per g dry weight (DW) doses of Osmocote™and struvite fertilizers were added to seagrass plots. Seagrass shoot counts were significantly higher in plots fertilized with struvite than both the Osmocote™and unfertilized controls (p< 0.0001). A significant difference in total P concentration was observed in porewater samples of Osmocote™vs struvite and controls (p< 0.0001), with struvite fertilized plots emitting more than controls (p ≤ 0.0001), but less than 2% of the total dissolved P (TDP) of Osmocote™fertilized plots (100+ mg/L versus x > 5 mg/L). A subsequent experiment, using smaller doses (0.01 and 0.025 mg of P per gram DW added), also found that the struvite treatments performed better than Osmocote™, with 16-114% more aboveground biomass (10-60% higher total biomass) while releasing less N and P. These results indicate the relatively rapid dissolution of Osmocote™may pose problems to restoration efforts, especially in concentrated doses and possibly leading to seagrass stress. In contrast, struvite may function as a slow-release fertilizer applicable in seagrass and other coastal restoration efforts.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Distal Brachial Artery Perforator flap: a new chimeric option for complex hand and digits defects

INTRODUCTION

Reconstruction of fingers pose unique challenges, as a thin and flexible flap is needed in order to guarantee a good functional outcome. For the first time, in this report, we present the DBAp (distal brachial artery perforator) flap, based on the distal perforator closer to the medial epicondyle. The DBAp flap was used to reconstruct complex digit defects as free flap, and to cover an elbow defect while raised as a propeller.

METHODS

Four patients underwent finger reconstruction (free flaps): two patients presented an unstable finger scar following previous surgery, whereas the other two patients presented a terminalized finger at the level of the middle phalanx. A further patient presented a post-traumatic loss of substance at the elbow and was reconstructed using a perforator propeller DBAP flap.

RESULTS

Loss of tissues included skin and subcutaneous tissue in all patients and in one patient it included a bone component. Flap dimensions ranged from 48 to 18 cm² (average: 32 cm²). Among complications, patient n.2 flap presented a marginal flap necrosis requiring a small skin graft after necrosis debridement.

CONCLUSION

The DBAp flap provides a slim, glabrous and pliable skin tissue with a well-hidden donor site scar and thanks to the anatomic location of the distal perforator can be designed to include a vascularized bone graft from the medial epicondyle. Despite the low number of cases, we believe that this flap should be considered as a dependable and effective source for complex reconstructions of both soft tissue and bone in fingers.

Microstructure and properties of additively manufactured Al-Ce-Mg alloys

Additive manufacturing of aluminum alloys is largely dominated by a near-eutectic Al-Si compositions, which are highly weldable, but have mechanical properties that are not competitive with conventional wrought Al alloys. In addition, there is a need for new Al alloys with improved high temperature properties and thermal stability for applications in the automotive and aerospace fields. In this work, we considered laser powder bed fusion additive manufacturing of two alloys in the Al–Ce–Mg system, designed as near-eutectic (Al–11Ce–7Mg) and hyper-eutectic (Al–15Ce–9Mg) compositions with respect to the binary L → Al + Al₁₁Ce eutectic reaction. The addition of magnesium is used to promote solid solution strengthening. A custom laser scan pattern was used to reduce the formation of keyhole porosity, which was caused by excessive vaporization due to the high vapor pressure of magnesium. The microstructure and tensile mechanical properties of the alloys were characterized in the as-fabricated condition and following hot isostatic pressing. The two alloys exhibit significant variations in solidification structure morphology. These variations in non-equilibrium solidification structure were rationalized using a combination of thermodynamic and thermal modeling. Both alloys showed higher yield strength than AM Al-10Si-Mg for temperatures up to 350 °C and better strength retention at elevated temperatures than additively manufactured Scalmaloy.

The majority of Swedish systemic lupus erythematosus patients are still affected by irreversible organ impairment: factors related to damage accrual in two regional cohorts

Background

Although the survival of patients with systemic lupus erythematosus (SLE) has improved, irreversible organ damage remains a critical concern. We aimed to characterize damage accrual and its clinical associations and causes of death in Swedish patients.

Methods

Accumulation of damage was evaluated in 543 consecutively recruited and well-characterized cases during 1998−2017. The Systemic Lupus International Collaborating Clinics (SLICC)/American College of Rheumatology damage index (SDI) was used to estimate damage.

Results

Organ damage (SDI ≥ 1) was observed in 59%, and extensive damage (SDI ≥ 3) in 25% of cases. SDI ≥ 1 was significantly associated with higher age at onset, SLE duration, the number of fulfilled SLICC criteria, neurologic disorder, antiphospholipid antibody syndrome (APS), hypertension, hyperlipidemia, depression and secondary Sjögren's syndrome (SS). In addition, SDI ≥ 3 was associated with serositis, renal and haematological disorders and interstitial lung disease. A multiple regression model identified not only well-known risk factors like APS, antihypertensives and corticosteroids, but pericarditis, haemolytic anaemia, lymphopenia and myositis as being linked to SDI. Malignancy, infection and cardiovascular disease were the leading causes of death.

Conclusions

After a mean SLE duration of 17 years, the majority of today's Swedish SLE patients have accrued damage. We confirm previous observations and report some novel findings regarding disease phenotypes and damage accrual.

Comparison between abdominal fat measured by CT and anthropometric indices as prediction factors for mortality and morbidity after colorectal surgery

AIM

This study aims to determine which anthropometric (body mass index (BMI), waist-hip-ratio (WHR) and waist-to-height ratio (WHtR)) and radiological (visceral fat area (VFA) measured by CT scan) measurements of adiposity correlated better with postoperative outcome of colorectal cancer (CRC) surgery. We also assessed which of these measurements best predicted overall survival (OS) and disease-free survival (DFS).

METHODS

Data from 90 consecutive Caucasian CRC patients who underwent surgery for colorectal cancer between 2010 and 2011 with a median follow-up of 53.25 months were analysed. The correlations of different adiposity measurements and postoperative outcomes were determined using logistic regression models and multivariate analyses.

RESULTS

Higher WHtR (p = 0.007) and VFA (p = 0.01) significantly increased the risk of overall morbidity, especially of Clavien-Dindo III or IV. The WHtR correlated best with VFA (p <0.0001), which is considered the gold standard for measuring visceral fat, whereas BMI (p = 0.15) was not a good predictor of postoperative morbidity. Multivariate analyses showed consistently significant results for postoperative complications for VFA in combination with all of the other variables analysed and for WHtR, confirming that VFA and WHtR were reliable independent prognostic factors of morbidity. VFA had a significant effect on OS (p = 0.012) but did not correlate with DFS (p = 0.51).

CONCLUSIONS

Both VFA and WHtR independently provided predictive data for potential postoperative complications after CRC surgery. In case CT scan was used for diagnostic purposes, VFA should be used in routine clinical practice.

Single-incision laparoscopic surgery for locally advanced colorectal cancer : feasibility, short-term and oncologic outcomes

BACKGROUND AND STUDY AIMS

Data about single-incision laparoscopic surgery (SILS) in locally advanced colorectal cancers are scarce. This study aimed to evaluate perioperative and shortterm oncologic outcomes of SILS in pT3-T4 colorectal cancer.

PATIENTS AND METHODS

From 2011 to 2015 data from 249 SILS performed in our Colorectal Unit were entered into a prospective database. Data regarding patients with a pT3-T4 colorectal adenocarcinoma were compared to those with pTis-pT2. Factors influencing conversion were assessed by multivariate analysis.

RESULTS

There were 100 consecutive patients (T3-T4 = 70, Tis-T2 = 30). Demographics were similar. Tumor size was significantly larger in the T3-T4 group [3.9cm vs 2cm; p<0.001]. In T3-T4 patients we found a significant higher number of lymph nodes harvested [20 vs 13 ; p<0.001]. Early (<30 days) severe (Clavien-Dindo classification>2) postoperative complication rate was similar between groups (8.6% vs 10% ; p = 0.999), as well as conversion rate (18.6% vs 6.7% ; p = 0.220). Finally, there were no differences in terms of hospital stay and mortality rate. On multivariate analysis, age (OR = 1.06, 95%CI: 1.012-1.113 ; p = 0.015] and stage IV (OR = 5.372, 95%CI: 1.320-21.862, p = 0.019) were independently associated with conversion.

CONCLUSIONS

SILS for locally advanced colorectal cancer did not affect the short-term outcomes in this series and oncological clearance remained satisfactory. Age and stage IV disease are independent risk factors for conversion.

Effects of depression, metabolic syndrome, and cardiorespiratory fitness on mortality: results from the Cooper Center Longitudinal Study

BACKGROUND

Depression and metabolic syndrome (MetS) are frequently comorbid disorders that are independently associated with premature mortality. Conversely, cardiorespiratory fitness (CRF) is associated with reduced mortality risk. These factors may interact to impact mortality; however, their effects have not been assessed concurrently. This analysis assessed the mortality risk of comorbid depression/MetS and the effect of CRF on mortality in those with depression/MetS.

METHODS

Prospective study of 47 702 adults in the Cooper Center Longitudinal Study. Mortality status was attained from the National Death Index. History of depression was determined by patient response (yes or no) to a standardized medical history questionnaire. MetS was categorized using the American Heart Association/National Heart, Lung, and Blood Institute criteria. CRF was estimated from the final speed/grade of a treadmill graded exercise test.

RESULTS

13.9% reported a history of depression, 21.4% met criteria for MetS, and 3.0% met criteria for both MetS and history of depression. History of depression (HR = 1.24, p = 0.003) and MetS (HR = 1.28, p < 0.001) were independently associated with an increased mortality risk, with the greatest mortality risk among individuals with both a history of depression and MetS (HR = 1.59, p < 0.001). Higher CRF was associated with a significantly lower risk of mortality (p < 0.001) in all individuals, including those with MetS and/or a history of depression.

CONCLUSIONS

Those with higher levels CRF had reduced mortality risk in the context of depression/MetS. Interventions that improve CRF could have substantial impact on the health of persons with depression/MetS.

ToF-SIMS Depth Profiling of PS-b-PMMA Block Copolymers Using Arn+, C60++, and Cs+ Sputtering Ions

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a high performance tool for molecular depth profiling of polymer films, in particular when they are structured in microphases. However, a major issue is the degradation of polymer materials under ion irradiation in reactions such as cross-linking, chain breaking, or reorganization processes of polymers which have been demonstrated for materials such as polystyrene (PS) and poly(methyl methacrylate) (PMMA). This work aims at comparing ToF-SIMS molecular depth profiling of structured polymers (polystyrene (PS)-b-polymethyl methacrylate (PMMA) block copolymers (BCP)) using either ultralow energy cesium or the more recently introduced C₆₀⁺⁺ (under NO dosing and with sample cooling) and argon cluster ion beams (using Ar₁₅₀₀⁺ ions at 5 keV). The latter improved the quality of the depth profiles, especially the argon cluster ion beam, as it is characterized by a greater homogeneity for the sputter yields of PS and PMMA. No significant artifacts were observed, and this was confirmed by the comparison of depth profiles obtained from films with variable thickness, annealing time, and morphology (cylindrical blocks vs spherical blocks). Comparison to a theoretical model (hexagonal centered pattern) ensured that the ToF-SIMS depth profiles described the real morphology and may thus be a relevant characterization tool to verify the morphology of the films as a function of the deposition parameters.

Lymph node ratio and surgical quality are strong prognostic factors of rectal cancer: results from a single referral centre

AIM

Nodal stage is a strong prognostic factor of oncological outcome of rectal cancer. To compensate for the variation in total number of harvested nodes, calculation of the lymph node ratio (LNR) has been advocated. The aim of the study was to compare the impact, on the long-term oncological outcome, of the LNR with other predictive factors, including the quality of total mesorectal excision (TME) and the state of the circumferential resection margin.

METHOD

Consecutive patients having elective surgery for nonmetastatic rectal cancer were extracted from a prospectively maintained database. Retrospective uni- and multivariate analyses were performed based on patient-, surgical- and tumour-related factors. The prognostic value of the LNR on overall survival (OS) and on overall recurrence-free survival (ORFS) was assessed and a cut-off value was determined.

RESULTS

From 1998 to 2013, out of 456 patients, 357 with nonmetastatic disease were operated on for rectal cancer. Neoadjuvant radiochemotherapy was administered to 66.7% of the patients. The mean number of lymph nodes retrieved was 12.8 ± 8.78 per surgical specimen. A lower lymph node yield was obtained in patients who received neoadjuvant chemoradiotherapy (11.8 vs 14.2; P = 0.014). The 5-year ORFS was 71.8% and the 5-year OS was 80.1%. Multivariate analysis confirmed LNR, the quality of TME and age to be independent prognostic factors of OS. LNR, age and perineural infiltration were independently associated with ORFS. Low- and high-risk patients could be discriminated using an LNR cut-off value of 0.2.

CONCLUSION

LNR is an independent prognostic factor of OS and ORFS. In line with the principles of optimal surgical management, the quality of TME and lymph node yield are essential technical requirements.

Scoring the quality of total mesorectal excision for the prediction of cancer-specific outcome

AIM

A three-grade system for macroscopic evaluation of the resection plane is used to describe the quality of total mesorectal excision (TME). In several studies, two of the three grades have been combined when analysing the outcome. The aim of our study was to compare the predictive value of the three-graded with that of a two-graded TME score.

METHOD

The quality of TME in 1382 patients who underwent elective resection for mid or low rectal adenocarcinoma was registered by 65 hospitals in PROCARE, a Belgian multidisciplinary improvement project. Prediction of outcome based on the classic three-grade score was compared with a two-grade scoring system in which intramesorectal resection (IMR) was combined with mesorectal (MRR) or with muscularis propria resection (MPR). End-points included the local recurrence rate, distant metastasis rate (DMR), disease-free survival (DFS) and overall survival (OS).

RESULTS

Among the 1382 resections, 63% were MRR, 27% IMR and 9% MPR. No significant differences were found in local recurrence between the different grades of TME. A two-grade score distinguishing MRR from the others was found to predict DMR, DFS and OS as well as the three-grade score.

CONCLUSION

The discriminatory and predictive value of a two-grade score, differentiating MRR from the combined IMR and MPR, was as good as the classic three-grade score.

Long head of biceps femoris flap in anal fistula treatment: anatomical study and case report

In case of complex anal fistulae, the treatment can include muscular flaps. The gracilis transposition flap is the gold-standard in perineal reconstructive surgery, with wide use during the past decades. However, in some cases, this flap is too short to reach difficult locations such as the posterior perineum. The long head of the biceps femoris, which has already been studied in the electrically stimulated neosphincter formation, could be more appropriate in such clinical situations. Furthermore, its potential advantages, amongst which an excellent functional outcome, would be to allow persistent prone position, during both treatment and reconstruction, as well as a more favorable intramuscular vascularisation. We report the case of a 39-year-old man with a complex recurrent transphincteric posterior anal fistula with an external orifice in the right buttock and complicated with a severe cellulitis, treated with an endo-anal flap combined with a long head of biceps femoris pediculised flap.

Correlations between technical skills and behavioral skills in simulated neonatal resuscitations

OBJECTIVE

Neonatal resuscitation requires both technical and behavioral skills. Key behavioral skills in neonatal resuscitation have been identified by the Neonatal Resuscitation Program. Correlations and interactions between technical skills and behavioral skills in neonatal resuscitation were investigated.

STUDY DESIGN

Behavioral skills were evaluated via blinded video review of 45 simulated neonatal resuscitations using a validated assessment tool. These were statistically correlated with previously obtained technical skill performance data.

RESULT

Technical skills and behavioral skills were strongly correlated (ρ=0.48; P=0.001). The strongest correlations were seen in distribution of workload (ρ=0.60; P=0.01), utilization of information (ρ=0.55; P=0.03) and utilization of resources (ρ=0.61; P=0.01). Teams with superior behavioral skills also demonstrated superior technical skills, and vice versa.

CONCLUSION

Technical and behavioral skills were highly correlated during simulated neonatal resuscitations. Individual behavioral skill correlations are likely dependent on both intrinsic and extrinsic factors.

Single point mutation in Rabenosyn-5 in a female with intractable seizures and evidence of defective endocytotic trafficking

BACKGROUND

We report a 6.5 year-old female with a homozygous missense mutation in ZFYVE20, encoding Rabenosyn-5 (Rbsn-5), a highly conserved multi-domain protein implicated in receptor-mediated endocytosis. The clinical presentation includes intractable seizures, developmental delay, microcephaly, dysostosis, osteopenia, craniofacial dysmorphism, macrocytosis and megaloblastoid erythropoiesis. Biochemical findings include transient cobalamin deficiency, severe hypertriglyceridemia upon ketogenic diet, microalbuminuria and partial cathepsin D deficiency.

METHODS AND RESULTS

Whole exome sequencing followed by Sanger sequencing confirmed a rare (frequency:0.003987) homozygous missense mutation, g.15,116,371 G > A (c.1273G > A), in ZFYVE20 resulting in an amino acid change from Glycine to Arginine at position 425 of the Rbsn protein (p.Gly425Arg), as the only mutation segregating with disease in the family. Studies in fibroblasts revealed expression and localization of Rbsn-5G425R in wild-type manner, but a 50% decrease in transferrin accumulation, which is corrected by wild-type allele transfection. Furthermore, the patient's fibroblasts displayed an impaired proliferation rate, cytoskeletal and lysosomal abnormalities.

CONCLUSION

These results are consistent with a functional defect in the early endocytic pathway resulting from mutation in Rbsn-5, which secondarily disrupts multiple cellular functions dependent on endocytosis, leading to a severe multi-organ disorder.

Effect of hospital volume on quality of care and outcome after rectal cancer surgery

BACKGROUND

Research on the relationship between hospital volume and quality of care in the treatment of rectal cancer is limited.

METHODS

Process and outcome indicators were assessed in patients with rectal adenocarcinoma who underwent total mesorectal excision, registered on a voluntary basis in the PROCARE clinical database. Volume was derived from an administrative database and analysed as a continuous variable. Sphincter preservation, 30-day mortality and survival rates were cross-checked against population-based data.

RESULTS

A total of 1469 patients registered in PROCARE between 2006 and 2011 were included in this study. A volume effect was observed regarding neoadjuvant therapy for stage II-III disease, reporting of the circumferential resection margin, R0 resection rate, sphincter preservation rate, and number of nodes examined after chemoradiotherapy. The global estimate of quality of care was highly variable, but surgery was the single domain in which quality correlated with volume. No volume effect was observed for recurrence and overall survival rates. In the population-based data set (5869 patients), volume was associated with 30-day mortality adjusted for age (odds ratio 0·99, 95 per cent confidence interval (c.i.) 0·98 to 1·00; P = 0·014) and adjusted overall survival (HR 0·99 (95 per cent c.i. 0·99 to 1·00) per additional procedure; P = 0·001), but not with the sphincter preservation rate. Because of incomplete and biased registration on a voluntary basis, results from a clinical database could not be extrapolated to the population.

CONCLUSION

Some volume effects were observed, but their effect size was limited.

Back to basics: iatrogenic intravenous cannula embolus

We present a case of distal venous embolisation of a peripheral intravenous cannula tip that had lost its structural integrity through repeated failed attempts of insertion of the same cannula, contrary to protocols for intravenous access. Radiological imaging confirmed the presence of a foreign body in the middle finger and the patient was brought to theatre. A 2.2cm long catheter tube was removed via a venotomy from the dorsal digital vein.

Exploring mesoscopic physics of vacancy-ordered systems through atomic scale observations of topological defects

Vacancy-ordered transition metal oxides have multiple similarities to classical ferroic systems including ferroelectrics and ferroelastics. The expansion coefficients for corresponding Ginzburg-Landau-type free energies are readily accessible from bulk phase diagrams. Here, we demonstrate that the gradient and interfacial terms can quantitatively be determined from the atomically resolved scanning transmission electron microscopy data of the topological defects and interfaces in model lanthanum-strontium cobaltite. With this knowledge, the interplay between ordering, chemical composition, and mechanical effects at domain walls, interfaces and structural defects can be analyzed.

Antibodies to cell surface proteins redirect intracellular trafficking pathways

Antibody-mediated intracellular delivery of therapeutic agents has been considered for treatment of a variety of diseases. These approaches involve targeting cell-surface receptor proteins expressed by tumors or viral proteins expressed on infected cells. We examined the intracellular trafficking of a viral cell-surface-expressed protein, rabies G, with or without binding a specific antibody, ARG1. We found that antibody binding shifts the native intracellular trafficking pathway of rabies G in an Fc-independent manner. Kinetic studies indicate that the ARG1/rabies G complex progressively co-localized with clathrin, early endosomes, late endosomes, and lysosomes after addition to cells. This pathway was different from that taken by rabies G without addition of antibody, which localized with recycling endosomes. Findings were recapitulated using a cellular receptor with a well-defined endogenous recycling pathway. We conclude that antibody binding to cell-surface proteins induces redirection of intracellular trafficking of unbound or ligand bound receptors to a specific degradation pathway. These findings have broad implications for future developments of antibody-based therapeutics.

Different surgical strategies in the treatment of familial adenomatous polyposis: what's the role of the ileal pouch-anal anastomosis?

BACKGROUND AND STUDY AIMS

Restorative coloproctectomy (RCP) with ileal pouch-anal anastomosis (IPAA), is one of the surgical responses to the crucial question of prophylactic treatment in familial adenomatous polyposis (FAP). No consensus has been reached, until now, to choose between IPAA and ileo-rectal anastomosis (IRA), the rectal sparing prophylactic colectomy. This paper aims to review the latest issues related to IPAA and highlights its specificities compared to IRA.

METHODS

PubMed database was searched using the following search items: familial adenomatous polyposis, surgery, ileal pouch-anal anastomosis, ileo-rectal anastomosis. Papers published between 1978 and 2010 were selected.

RESULTS

Absence of mortality, acceptable morbidity and good functional results combined to high quality of life have promoted the IPAA technique. New technical issues such as the double stapled technique, mesenteric lengthening, omission of temporary protective stoma can be addressed almost systematically for these patients. A laparoscopic approach, lessening the body image impact, has proven to be as effective and safe as the open approach to perform IPAA. Further advantages of laparoscopic IPAA rely on the lower adhesion formation resulting in less small bowel occlusion. Sexuality, fertility and childbirth are important functional issues often cited as threatened by the pelvic manoeuvres of the IPAA technique which can be prevented by close rectal wall dissection and a laparoscopic approach.

CONCLUSION

IPAA offers the best available prophylaxis in FAP patients. Technical enhancements in IPAA will most probably decrease the functional risks. Thus IPAA remains the alternative to IRA for the prophylactic treatment of FAP.Nevertheless, based on the latest evidence, the choice between both procedures is still matter of debate.

Sorting of EGF and transferrin at the plasma membrane and by cargo-specific signaling to EEA1-enriched endosomes

The biological function of receptors is determined by their appropriate trafficking through the endosomal pathway. Following internalization, the transferrin (Tf) receptor quantitatively recycles to the plasma membrane, whereas the epidermal growth factor (EGF) receptor undergoes degradation. To determine how Tf and EGF engage these two different pathways we imaged their binding and early endocytic pathway in live cells using total internal reflection fluorescence microscopy (TIRF-M). We find that EGF and Tf bind to distinct plasma membrane regions and are incorporated into different endocytic vesicles. After internalization, both EGF-enriched and Tf-enriched vesicles interact with endosomes containing early endosome antigen 1 (EEA1). EGF is incorporated and retained in these endosomes, while Tf-containing vesicles rapidly dissociate and move to a juxtanuclear compartment. Endocytic vesicles carrying EGF recruit more Rab5 GTPase than those carrying Tf, which, by strengthening their association with EEA1-enriched endosomes, may provide a mechanism for the observed cargo-specific sorting. These results reveal pre-endocytic sorting of Tf and EGF, a specialized role for EEA1-enriched endosomes in EGF trafficking, and a potential mechanism for cargo-specified sorting of endocytic vesicles by these endosomes.

Evolutionarily conserved structural and functional roles of the FYVE domain

The FYVE domain is an approx. 80 amino acid motif that binds to the phosphoinositide PtdIns3P with high specificity and affinity. It is present in 38 predicted gene products within the human genome, but only in 12-13 in Caenorhabditis elegans and Drosophila melanogaster. Eight of these are highly conserved in all three organisms, and they include proteins that have not been characterized in any species. One of these, WDFY2, appears to play an important role in early endocytosis and was revealed in a RNAi (RNA interference) screen in C. elegans. Interestingly, some proteins contain FYVE-like domains in C. elegans and D. melanogaster, but have lost this domain during evolution. One of these is the homologue of Rabatin-5, a protein that, in mammalian cells, binds both Rab5 and Rabex-5, a guanine-nucleotide exchange factor for Rab5. Thus the Rabatin-5 homologue suggests that mechanisms to link PtdIns3P and Rab5 activation developed in evolution. In mammalian cells, these mechanisms are apparent in the existence of proteins that bind PtdIns3P and Rab GTPases, such as EEA1, Rabenosyn-5 and Rabip4'. Despite the comparable ability to bind to PtdIns3P in vitro, FYVE domains display widely variable abilities to interact with endosomes in intact cells. This variation is due to three distinct properties of FYVE domains conferred by residues that are not involved in PtdIns3P head group recognition: These properties are: (i) the propensity to oligomerize, (ii) the ability to insert into the membrane bilayer, and (iii) differing electrostatic interactions with the bilayer surface. The different binding properties are likely to regulate the extent and duration of the interaction of specific FYVE domain-containing proteins with early endosomes, and thereby their biological function.

The WD40 and FYVE domain containing protein 2 defines a class of early endosomes necessary for endocytosis

The FYVE domain binds with high specificity and avidity to phosphatidylinositol 3-phosphate. It is present in approximately 30 proteins in humans, some of which have been implicated in functions ranging from early endosome fusion to signal transduction through the TGF-beta receptor. To develop a further understanding of the biological roles of this protein family, we turned to the nematode Caenorhabditis elegans, which contains only 12 genes predicted to encode for phosphatidylinositol 3-phosphate binding, FYVE domain-containing proteins, all of which have homologs in the human genome. Each of these proteins was targeted individually by RNA interference. One protein, WDFY2, produced a strong inhibition of endocytosis when silenced. WDFY2 contains WD40 motifs and a FYVE domain, is highly conserved between species, and localizes to a set of small endosomes that reside within 100 nm from the plasma membrane. These endosomes are involved in transferrin uptake but lack the classical endosomal markers Rab5 and EEA1. Silencing of WDFY2 by siRNA in mammalian cells impaired transferrin endocytosis. These studies reveal the important, conserved role of WDFY2 in endocytosis, and the existence of a subset of early endosomes, closely associated with the plasma membrane, that may constitute the first stage of endocytic processing of internalized cargo.

Plasma Membrane Domains Specialized for Clathrin-mediated Endocytosis in Primary Cells

Clathrin assembly at the plasma membrane is a fundamental process required for endocytosis. In cultured cells, most of the clathrin is localized to large patches that display little lateral mobility. The functional role of these regions is not clear, and it has been thought that they may represent artifacts of cell adhesion of cultured cells. Here we have analyzed clathrin organization in primary adipose cells isolated from mice, which are nonadherent and fully differentiated. The majority of clathrin on the plasma membrane of these cells (>60%) was found in large clathrin patches that displayed virtually no lateral mobility and persisted for many minutes, and a smaller amount was found in small spots that appeared and disappeared rapidly. Direct visualization of transferrin revealed that it bound onto large arrays of clathrin, internalizing through vesicles that emerge from these domains. High resolution imaging (50 images/s) revealed fluorescence intensity fluctuations consistent with the formation and detachment of coated vesicles from within large patches. These results reveal that large clathrin assemblies are active regions of endocytosis in mammalian cells and highlight the importance of understanding the mechanistic basis for this organization.

Cement pressurisation in the acetabulum

Cement pressurisation is an important step in total hip arthroplasty that determines the long-term integration at the cement-bone interface. Our aim was to evaluate the performance of a new pressuriser designed by us against the standard existing pressurisers in an in vitro experimental set-up using two parameters: cement penetration and cement pressurisation. A polypropylene cup model was designed to represent the acetabulum. DePuy's T-handle, Exeter and our own plunger type pressuriser were each tested for cement pressurisation in this acetabular model. Cement penetration and pressures were measured. The cement intrusion into the capillaries with the DePuy pressuriser was found to vary between 2 and 8 mm (mean: 5 mm at the pole and 4.6 mm at the rim), with the Exeter pressuriser it varied between 3 and 9 mm (mean: 5.8 mm at the pole and 7.8 mm at the rim) and with the plunger type pressuriser it varied between 4 and 6 mm (mean 5.2 mm at the pole and 4.8 mm at the rim). The peak pressure achieved with the DePuy pressuriser was 60 kPa whereas it was 70 kPa with the plunger type pressuriser. The mean penetration with the plunger type pressuriser was found to be better than the other types. The penetration was found to be more uniform with equal penetration at the rim as well as at the pole.

Validation of the small-punch test as a technique for characterizing the mechanical properties of acrylic bone cement

This paper examines the validity of using the small-punch test technique as a means of quantifying the mechanical properties of acrylic bone cement under different test conditions. The elastic moduli calculated using the small-punch test method were compared with data measured using the international standard for acrylic bone resin, ISO 5833. Conclusions from the study indicate that the small-punch test is a reproducible miniature specimen test method that can be used to characterize the mechanical properties of retrieved acrylic bone cement as used in total joint replacement surgery. Moreover, the test conditions were found to influence the elastic modulus of acrylic bone cement. The test temperature had a greater effect on the elastic behaviour of the bone cement than the test medium.

Experimental investigation of geologically produced antineutrinos with KamLAND

The detection of electron antineutrinos produced by natural radioactivity in the Earth could yield important geophysical information. The Kamioka liquid scintillator antineutrino detector (KamLAND) has the sensitivity to detect electron antineutrinos produced by the decay of 238U and 232Th within the Earth. Earth composition models suggest that the radiogenic power from these isotope decays is 16 TW, approximately half of the total measured heat dissipation rate from the Earth. Here we present results from a search for geoneutrinos with KamLAND. Assuming a Th/U mass concentration ratio of 3.9, the 90 per cent confidence interval for the total number of geoneutrinos detected is 4.5 to 54.2. This result is consistent with the central value of 19 predicted by geophysical models. Although our present data have limited statistical power, they nevertheless provide by direct means an upper limit (60 TW) for the radiogenic power of U and Th in the Earth, a quantity that is currently poorly constrained.