Lagrangian betweenness as a measure of bottlenecks in dynamical systems with oceanographic examples

The study of connectivity patterns in networks has brought novel insights across diverse fields ranging from neurosciences to epidemic spreading or climate. In this context, betweenness centrality has demonstrated to be a very effective measure to identify nodes that act as focus of congestion, or bottlenecks, in the network. However, there is not a way to define betweenness outside the network framework. By analytically linking dynamical systems and network theory, we provide a trajectory-based formulation of betweenness, called Lagrangian betweenness, as a function of Lyapunov exponents. This extends the concept of betweenness beyond the context of network theory relating hyperbolic points and heteroclinic connections in any dynamical system to the structural bottlenecks of the network associated with it. Using modeled and observational velocity fields, we show that such bottlenecks are present and surprisingly persistent in the oceanic circulation across different spatio-temporal scales and we illustrate the role of these areas in driving fluid transport over vast oceanic regions. Analyzing plankton abundance data from the Kuroshio region of the Pacific Ocean, we find significant spatial correlations between measures of diversity and betweenness, suggesting promise for ecological applications.

The cyto-protective effects of LH on ovarian reserve and female fertility during exposure to gonadotoxic alkylating agents in an adult mouse model

STUDY QUESTION

Does LH protect mouse oocytes and female fertility from alkylating chemotherapy?

SUMMARY ANSWER

LH treatment before and during chemotherapy prevents detrimental effects on follicles and reproductive lifespan.

WHAT IS KNOWN ALREADY

Chemotherapies can damage the ovary, resulting in premature ovarian failure and reduced fertility in cancer survivors. LH was recently suggested to protect prepubertal mouse follicles from chemotoxic effects of cisplatin treatment.

STUDY DESIGN, SIZE, DURATION

This experimental study investigated LH effects on primordial follicles exposed to chemotherapy. Seven-week-old CD-1 female mice were randomly allocated to four experimental groups: Control (n = 13), chemotherapy (ChT, n = 15), ChT+LH-1x (n = 15), and ChT+LH-5x (n = 8). To induce primary ovarian insufficiency (POI), animals in the ChT and ChT+LH groups were intraperitoneally injected with 120 mg/kg of cyclophosphamide and 12 mg/kg of busulfan, while control mice received vehicle. For LH treatment, the ChT+LH-1x and ChT+LH-5x animals received a 1 or 5 IU LH dose, respectively, before chemotherapy, then a second LH injection administered with chemotherapy 24 h later. Then, two animals/group were euthanized at 12 and 24 h to investigate the early ovarian response to LH, while remaining mice were housed for 30 days to evaluate short- and long-term reproductive outcomes. The effects of LH and chemotherapy on growing-stage follicles were analyzed in a parallel experiment. Seven-week-old NOD-SCID female mice were allocated to control (n = 5), ChT (n = 5), and ChT+LH-1x (n = 6) groups. Animals were treated as described above, but maintained for 7 days before reproductive assessment.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In the first experiment, follicular damage (phosphorylated H2AX histone (γH2AX) staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay), apoptotic biomarkers (western blot), and DNA repair pathways (western blot and RT-qPCR) were assessed in ovaries collected at 12 and 24 h to determine early ovarian responses to LH. Thirty days after treatments, remaining mice were stimulated (10 IU of pregnant mare serum gonadotropin (PMSG) and 10 IU of hCG) and mated to collect ovaries, oocytes, and embryos. Histological analysis was performed on ovarian samples to investigate follicular populations and stromal status, and meiotic spindle and chromosome alignment was measured in oocytes by confocal microscopy. Long-term effects were monitored by assessing pregnancy rate and litter size during six consecutive breeding attempts. In the second experiment, mice were stimulated and mated 7 days after treatments and ovaries, oocytes, and embryos were collected. Follicular numbers, follicular protection (DNA damage and apoptosis by H2AX staining and TUNEL assay, respectively), and ovarian stroma were assessed. Oocyte quality was determined by confocal analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

LH treatment was sufficient to preserve ovarian reserve and follicular development, avoid atresia, and restore ovulation and meiotic spindle configuration in mature oocytes exposed at the primordial stage. LH improved the cumulative pregnancy rate and litter size in six consecutive breeding rounds, confirming the potential of LH treatment to preserve fertility. This protective effect appeared to be mediated by an enhanced early DNA repair response, via homologous recombination, and generation of anti-apoptotic signals in the ovary a few hours after injury with chemotherapy. This response ameliorated the chemotherapy-induced increase in DNA-damaged oocytes and apoptotic granulosa cells. LH treatment also protected growing follicles from chemotherapy. LH reversed the chemotherapy-induced depletion of primordial and primary follicular subpopulations, reduced oocyte DNA damage and granulosa cell apoptosis, restored mature oocyte cohort size, and improved meiotic spindle properties.

LARGE SCALE DATA

N/A.

LIMITATIONS, REASONS FOR CAUTION

This was a preliminary study performed with mouse ovarian samples. Therefore, preclinical research with human samples is required for validation.

WIDER IMPLICATIONS OF THE FINDINGS

The current study tested if LH could protect the adult mouse ovarian reserve and reproductive lifespan from alkylating chemotherapy. These findings highlight the therapeutic potential of LH as a complementary non-surgical strategy for preserving fertility in female cancer patients.

STUDY FUNDING/COMPETING INTEREST(S)

This study was supported by grants from the Regional Valencian Ministry of Education (PROMETEO/2018/137), the Spanish Ministry of Science and Innovation (CP19/00141), and the Spanish Ministry of Education, Culture and Sports (FPU16/05264). The authors declare no conflict of interest.

Managing chronic disease in the COVID-19 pandemic: an e-learning application to promote a healthy lifestyle for persons with multiple sclerosis

E-health applications can support continuing care for persons with chronic diseases such as multiple sclerosis (MS). We have developed a web-based mobile app called VIOLA to be used at home by persons with MS (pwMS) who previously participated in an innovative multidisciplinary rehab program. The purpose of VIOLA is to reinforce what participants have learned about a healthy lifestyle and to keep them motivated to adhere to rehabilitation programs. As the outbreak of the Covid-19 pandemic has severely curtailed pwMS contact with their usual health providers, we quickly updated VIOLA to grant continuity of care to our home-bound patients.By monitoring pwMS subscriptions to individual modules, we found a definite increase after the national lockdown was declared. Subscribers rated the app very positively.Encouraged by the positive feedbacks, we are planning to extend the access to our app also to pwMS with no prior specific learning experience. This would limit the psychophysical consequences of the lockdown. Furthermore, VIOLA could be effective in maintaining a proper lifestyle, contributing to improve the quality of life of pwMS.VIOLA has the potential of increasing the adherence of pwMS to the rehabilitation confirming that digital communication tools are a valuable solution for those home-bound.].

Future changes to the upper ocean Western Boundary Currents across two generations of climate models

Western Boundary Currents (WBCs) are important for the oceanic transport of heat, dissolved gases and nutrients. They can affect regional climate and strongly influence the dispersion and distribution of marine species. Using state-of-the-art climate models from the latest and previous Climate Model Intercomparison Projects, we evaluate upper ocean circulation and examine future projections, focusing on subtropical and low-latitude WBCs. Despite their coarse resolution, climate models successfully reproduce most large-scale circulation features with ensemble mean transports typically within the range of observational uncertainty, although there is often a large spread across the models and some currents are systematically too strong or weak. Despite considerable differences in model structure, resolution and parameterisations, many currents show highly consistent projected changes across the models. For example, the East Australian Current, Brazil Current and Agulhas Current extensions are projected to intensify, while the Gulf Stream, Indonesian Throughflow and Agulhas Current are projected to weaken. Intermodel differences in most future circulation changes can be explained in part by projected changes in the large-scale surface winds. In moving to the latest model generation, despite structural model advancements, we find little systematic improvement in the simulation of ocean transports nor major differences in the projected changes. 

Explicit and implicit network connectivity: Analytical formulation and application to transport processes

Connectivity is a fundamental structural feature of a network that determines the outcome of any dynamics that happens on top of it. However, an analytical approach to obtain connection probabilities between nodes associated with to paths of different lengths is still missing. Here, we derive exact expressions for random-walk connectivity probabilities across any range of numbers of steps in a generic temporal, directed, and weighted network. This allows characterizing explicit connectivity realized by causal paths as well as implicit connectivity related to motifs of three nodes and two links called here pitchforks. We directly link such probabilities to the processes of tagging and sampling any quantity exchanged across the network, hence providing a natural framework to assess transport dynamics. Finally, we apply our theoretical framework to study ocean transport features in the Mediterranean Sea. We find that relevant transport structures, such as fluid barriers and corridors, can generate contrasting and counterintuitive connectivity patterns bringing novel insights into how ocean currents drive seascape connectivity.

Mild and Severe Obesity Reduce the Effectiveness of Lumbar Fusions: 1-Year Patient-Reported Outcomes in 8171 Patients

BACKGROUND

Elevated body mass index (BMI) is a well-known risk factor for surgical complications in lumbar surgery. However, its effect on surgical effectiveness independent of surgical complications is unclear.

OBJECTIVE

To determine increasing BMI's effect on functional outcomes following lumbar fusion surgery, independent of surgical complications.

METHODS

We retrospectively analyzed a prospectively built, patient-reported, quality of life registry representing 75 hospital systems. We evaluated 1- to 3-level elective lumbar fusions. Patients who experienced surgical complications were excluded. A stepwise multivariate regression model assessed factors independently associated with 1-yr Oswestry Disability Index (ODI), preop to 1-yr ODI change, and achievement of minimal clinically important difference (MCID).

RESULTS

A total of 8171 patients met inclusion criteria: 2435 with class I obesity (BMI 30-35 kg/m2), 1328 with class II (35-40 kg/m2), and 760 with class III (≥40 kg/m2). Increasing BMI was independently associated with worse 12-mo ODI (t = 8.005, P < .001) and decreased likelihood of achieving MCID (odds ratio [OR] = 0.977, P < .001). One year after surgery, mean ODI, ODI change, and percentage achieving MCID worsened with class I, class II, and class III vs nonobese cohorts (P < .001) in stepwise fashion.

CONCLUSION

Increasing BMI is associated with decreased effectiveness of 1- to 3-level elective lumbar fusion, despite absence of surgical complications. BMI ≥ 30 kg/m2 is, therefore, a risk factor for both surgical complication and reduced benefit from lumbar fusion.

Preoperative Acetazolamide Challenge in Pediatric Chiari I Malformation

PURPOSE

In patients who present with headaches and Chiari 1 malformation without cranial nerve or brainstem dysfunction or syrinx formation, the decision to decompress can be difficult to make. We present a case series examining the use of acetazolamide as a diagnostic aid to determine candidacy for decompression.

METHODS

A single pediatric neurosurgeon's (M.M.H.) experience from 2003 to 2018 was retrospectively reviewed. All cases evaluated in the clinic for CPT code of Chiari 1 malformation were analyzed. Inclusion criteria were patients with diagnosis of Chiari 1 malformation and headache-predominant symptoms who underwent an acetazolamide challenge test. Exclusion criteria included age over 18, syrinx, or significant clinical evidence of brainstem compression or cranial nerve dysfunction. Data were recorded with respect to response to acetazolamide. Surgical outcomes were assessed using the Chicago Chiari Outcome Scale (CCOS) pain category and the improve/same/worse (IWS) scale. Overall satisfaction from surgery was also recorded.

RESULTS

Forty-five patients met inclusion criteria and underwent acetazolamide challenge. Thirty-three (73.3%) patients showed improvement of their symptoms with acetazolamide challenge (responders). Of the 33 responders, 25 (75.8%) underwent Chiari decompression. The remaining 8 (24.2%) responders experienced persistent improvement of their symptoms after the acetazolamide trial and did not require intervention. Twelve (26.7%) patients did not improve with acetazolamide (nonresponders) of which 11 (91.7% of nonreponders) never required intervention. One nonresponder eventually underwent Chiari decompression due to progressively worsening and debilitating headaches. All twenty-five (100%) responders improved after surgery and 24 (96%) were satisfied with the outcome of surgery. The average responder CCOS pain score was 3.52 out of 4. The nonresponder who did not improve with acetazolamide had persistent severe headaches after decompression. The CCOS pain score for this nonresponder was 2 out of 4.

CONCLUSION

Pediatric headache-predominant Chiari 1 malformation presents a difficult diagnostic dilemma. The authors describe a trial of acetazolamide as a preoperative diagnostic tool to aid the decision to decompress. Further studies will need to be performed to determine the effectiveness of preoperative acetazolamide in identifying which patients may benefit from surgical decompression.

Bidirectional Expandable Technology for Transforaminal or Posterior Lumbar Interbody Fusion: A Retrospective Analysis of Safety and Performance

BACKGROUND

Expandable devices for transforaminal or posterior lumbar interbody fusion (TLIF and PLIF, respectively) may enable greater restoration of disc height, foraminal height, and stability within the interbody space than static spacers. Medial-lateral expansion may also increase stability and resistance to subsidence. This study evaluates the clinical and radiographic outcomes from early experience with a bidirectional expandable device.

METHODS

This was a retrospective analysis of a continuous series of patients across 3 sites who had previously undergone TLIF or PLIF surgery with a bidirectional expandable interbody fusion device (FlareHawk, Integrity Implants, Inc) at 1 or 2 contiguous levels between L2 and S1. Outcomes included the Oswestry Disability Index (ODI), a visual analog scale (VAS) for back pain or leg pain, radiographic fusion by 1 year of follow-up, subsidence, device migration, and adverse events (AE).

RESULTS

There were 58 eligible patients with radiographs for 1-year fusion assessments and 45 patients with ODI, VAS back pain, or VAS leg pain data at baseline and a mean follow-up of 4.5 months. The ODI, VAS back pain, and VAS leg pain scores improved significantly from baseline to final follow-up, with mean improvements of 14.6 ± 19.1, 3.4 ± 2.6, and 3.9 ± 3.4 points (P < .001 for each), respectively. In addition, 58% of patients achieved clinically significant improvements in ODI, 76% in VAS back pain, and 71% in VAS leg pain. By 1 year, 96.6% of patients and 97.4% of levels were considered fused. There were zero cases of device subsidence and 1 case of device migration (1.7%). There were zero device-related AEs, 1 intraoperative dural tear, and 3 subsequent surgical interventions.

CONCLUSIONS

The fusion rate, improvements in patient-reported outcomes, and the AEs observed are consistent with those of other devices. The bidirectional expansion mechanism may provide other important clinical value, but further studies will be required to elucidate the unique advantages.

LEVEL OF EVIDENCE

4.

The Institute for Healthcare Improvement-NeuroPoint Alliance collaboration to decrease length of stay and readmission after lumbar spine fusion: using national registries to design quality improvement protocols

OBJECTIVE

National databases collect large amounts of clinical information, yet application of these data can be challenging. The authors present the NeuroPoint Alliance and Institute for Healthcare Improvement (NPA-IHI) program as a novel attempt to create a quality improvement (QI) tool informed through registry data to improve the quality of care delivered. Reducing the length of stay (LOS) and readmission after elective lumbar fusion was chosen as the pilot module.

METHODS

The NPA-IHI program prospectively enrolled patients undergoing elective 1- to 3-level lumbar fusions across 8 institutions. A three-pronged approach was taken that included the following phases: 1) Research Phase, 2) Development Phase, and 3) Implementation Phase. Primary outcomes were LOS and readmission. From January to June 2017, a learning system was created utilizing monthly conference calls, weekly data submission, and continuous refinement of the proposed QI tool. Nonparametric tests were used to assess the impact of the QI intervention.

RESULTS

The novel QI tool included the following three areas of intervention: 1) preoperative discharge assessment (location, date, and instructions), 2) inpatient changes (LOS rounding checklist, daily huddle, and pain assessments), and 3) postdischarge calls (pain, primary care follow-up, and satisfaction). A total of 209 patients were enrolled, and the most common procedure was a posterior laminectomy/fusion (60.2%). Seven patients (3.3%) were readmitted during the study period. Preoperative discharge planning was completed for 129 patients (61.7%). A shorter median LOS was seen in those with a known preoperative discharge date (67 vs 80 hours, p = 0.018) and clear discharge instructions (71 vs 81 hours, p = 0.030). Patients with a known preoperative discharge plan also reported significantly increased satisfaction (8.0 vs 7.0, p = 0.028), and patients with increased discharge readiness (scale 0-10) also reported higher satisfaction (r = 0.474, p < 0.001). Those receiving postdischarge calls (76%) had a significantly shorter LOS than those without postdischarge calls (75 vs 99 hours, p = 0.020), although no significant relationship was seen between postdischarge calls and readmission (p = 0.342).

CONCLUSIONS

The NPA-IHI program showed that preoperative discharge planning and postdischarge calls have the potential to reduce LOS and improve satisfaction after elective lumbar fusion. It is our hope that neurosurgical providers can recognize how registries can be used to both develop and implement a QI tool and appreciate the importance of QI implementation as a separate process from data collection/analysis.

Ovarian damage from chemotherapy and current approaches to its protection

BACKGROUND

Anti-cancer therapy is often a cause of premature ovarian insufficiency and infertility since the ovarian follicle reserve is extremely sensitive to the effects of chemotherapy and radiotherapy. While oocyte, embryo and ovarian cortex cryopreservation can help some women with cancer-induced infertility achieve pregnancy, the development of effective methods to protect ovarian function during chemotherapy would be a significant advantage.

OBJECTIVE AND RATIONALE

This paper critically discusses the different damaging effects of the most common chemotherapeutic compounds on the ovary, in particular, the ovarian follicles and the molecular pathways that lead to that damage. The mechanisms through which fertility-protective agents might prevent chemotherapy drug-induced follicle loss are then reviewed.

SEARCH METHODS

Articles published in English were searched on PubMed up to March 2019 using the following terms: ovary, fertility preservation, chemotherapy, follicle death, adjuvant therapy, cyclophosphamide, cisplatin, doxorubicin. Inclusion and exclusion criteria were applied to the analysis of the protective agents.

OUTCOMES

Recent studies reveal how chemotherapeutic drugs can affect the different cellular components of the ovary, causing rapid depletion of the ovarian follicular reserve. The three most commonly used drugs, cyclophosphamide, cisplatin and doxorubicin, cause premature ovarian insufficiency by inducing death and/or accelerated activation of primordial follicles and increased atresia of growing follicles. They also cause an increase in damage to blood vessels and the stromal compartment and increment inflammation. In the past 20 years, many compounds have been investigated as potential protective agents to counteract these adverse effects. The interactions of recently described fertility-protective agents with these damage pathways are discussed.

WIDER IMPLICATIONS

Understanding the mechanisms underlying the action of chemotherapy compounds on the various components of the ovary is essential for the development of efficient and targeted pharmacological therapies that could protect and prolong female fertility. While there are increasing preclinical investigations of potential fertility preserving adjuvants, there remains a lack of approaches that are being developed and tested clinically.

Anterior Cervical Discectomy and Fusion in the Outpatient Ambulatory Surgery Setting: Analysis of 2000 Consecutive Cases

BACKGROUND

In an effort to improve efficiency of care, ambulatory surgery centers (ASCs) have emerged as lower-cost options. Anterior cervical discectomy and fusion (ACDF) is one of the most prevalent spine surgeries performed and rarely requires overnight stays in the hospital, supporting its migration to the ASC. Recent analyses have called into question the safety of outpatient ACDF, potentially slowing its adoption. ASC-ACDF studies have largely been limited to small series, precluding an accurate assessment of safety.

OBJECTIVE

To analyze 2000 ASC-ACDF cases, describe patient selection and perioperative protocol, and report associated safety profile.

METHODS

A total of 2000 patients who underwent 1 to 3 level ACDF in a single ASC from 2006 to 2018 were included in this retrospective analysis. Patients were observed in a 4-h postanesthesia care unit (PACU) with a multimodal pain management regiment. Data were collected on patient demographics, comorbidities, operative details, and 30- and 90-d morbidity.

RESULTS

Of the 2000 patients, 10 (0.5%) required transfer to an inpatient setting within the 4-h observation. Reasons for transfer included hematoma (2), pain control (2), cerebrospinal fluid leak (1), and medical complications (5). Six patients (0.3%) underwent reoperation within 30 d. All-cause 30-d readmission was 1.9%.

CONCLUSION

An analysis of 2000 ACDF patients in an ASC setting with a standardized perioperative protocol demonstrates that surgical complications occur at a low rate (&lt;1%) and can be appropriately diagnosed and managed in a 4-h PACU. In an effort to decrease healthcare costs, surgeons can safely perform ACDFs in an ASC utilizing patient selection criteria and perioperative management protocols similar to those reported here.

Outpatient anterior cervical discectomy and fusion in the ambulatory surgery center setting: safety assessment for the Medicare population

OBJECTIVE

Several studies have demonstrated that anterior cervical discectomy and fusion (ACDF) surgery in the outpatient versus hospital setting provides improved efficiency, cost-effectiveness, and patient satisfaction without a compromise in safety or outcome. Recent anecdotal reports, however, have questioned whether outpatient ACDF surgery is safe in the > 65-year-old Medicare population. To date, no clinical study has assessed the safety of outpatient ACDF in an ambulatory surgery center (ASC), specifically in a Medicare population. The authors set out to analyze their 3-year experience with Medicare-enrolled patients undergoing ACDF surgery at a single ASC to determine its safety profile, perioperative care protocol, and associated outcomes.

METHODS

A retrospective analysis of 119 consecutive patients > 65 years (Medicare-eligible) who underwent 1-, 2-, or 3-level ACDF at a single ASC from 2015 to 2018 (since Medicare payment approval) was conducted. All patients were in American Society of Anesthesiologists classes I-III. Postoperatively, patients were observed for a minimum of 4 hours in a recovery setting for the following factors: neck swelling, neurological status, ability to swallow solid food, and urination capacity. All patients received a multimodal pain management regimen prior to discharge home. Data were collected on patient demographics, comorbidities, operative details, and all perioperative and 90-day morbidity.

RESULTS

Complete data were available for all 119 consecutive Medicare-eligible patients, 97 (81.5%) of whom were actively enrolled in Medicare. One-, 2-, and 3-level ACDFs were performed in 103 (86.6%), 15 (12.6%), and 1 (0.8%) patients, respectively. No patients required return to the operating room for intervention within the 4-hour postanesthesia care unit observation window. No patients required transfer from the ASC to the hospital setting for further observation or intervention. Thirty-day adverse events were reported in 2.4% of cases, all of which resolved by 90 days after surgery. The incidence of 90-day hospital readmission was 1.7% (n = 2), with 1 patient (0.8%) requiring reoperation at the index level for deep infection. All-cause 90-day mortality was 0%.

CONCLUSIONS

An analysis of consecutive Medicare patients (American Society of Anesthesiologists classes I-III) who underwent mostly 1-level and some 2-level ACDFs in an ASC setting demonstrates that surgical complications occur at a low rate with a safety profile similar to that reported for both inpatient ACDF and patients younger than 65 years. In an effort to reduce cost and improve efficiency of care, surgeons can safely perform ACDF in the Medicare population in an ASC environment utilizing patient selection criteria and perioperative management similar to those reported here.

A multidisciplinary analytical framework to delineate spawning areas and quantify larval dispersal in coastal fish

Assessing larval dispersal is essential to understand the structure and dynamics of marine populations. However, knowledge about early-life dispersal is sparse, and so is our understanding of the spawning process, perhaps the most obscure component of biphasic life cycles. Indeed, poorly known species-specific spawning modality and species-specific early-life traits, as well as the high spatio-temporal variability of the oceanic circulation experienced during larval drift, hamper our ability to appraise the realized connectivity of coastal fishes. Here, we propose an analytical framework which combines Lagrangian modelling, network theory, otolith analyses and biogeographical information to pinpoint and characterize larval sources which are then grouped into discrete spawning areas. Such well-delineated larval sources allow improving the quantitative evaluations of both dispersal scales and connectivity patterns. To illustrate its added value, our approach is applied to two case-studies focusing on Diplodus sargus and Diplodus vulgaris in the Adriatic sea. We evidence robust correlations between otolith geochemistry and modelled spawning areas to assess their relative importance for the larval replenishment of the Apulian coast. Our results show that, contrary to D. sargus, D. vulgaris larvae originate from both eastern and western Adriatic shorelines. Our findings also suggest that dispersal distances and dispersal surfaces scale differently with the pelagic larval duration. Furthermore, 30.8% of D. sargus larvae and 23.6% of D. vulgaris larvae of the Apulian populations originate from Marine protected area (MPA), exemplifying larval export from MPAs to surrounding unprotected areas. This flexible multidisciplinary framework, which can be adjusted to any coastal fish and oceanic system, exploits the explanatory power of a dispersal model, fine-tuned and backed-up by observations, to provide more reliable scientific basis for the management and conservation of marine ecosystems.

Efficacy, Tolerability, and Safety of Low-Volume Bowel Preparations for Patients with Inflammatory Bowel Diseases: The French Multicentre CLEAN Study

BACKGROUND

Standard high-volume polyethylene glycol [PEG] bowel preparations [PEG-4L] are recommended for patients with inflammatory bowel disease [IBD] undergoing colonoscopy. However, low-volume preparations [≤2 L of active volume] are often used in clinical practice. The aim of this study was to evaluate the efficacy, tolerability, and safety of the various bowel preparations for patients with IBD, including low-volume preparations.

METHODS

We conducted a French prospective multicentre observational study over a period of 1 month. Patients aged 18-75 years with IBD with an indication of colonoscopy independent of the study were enrolled. The choice of the preparation was left to the investigators, as per their usual protocol. The patients' characteristics, disease, and colonoscopy characteristics were recorded, and they were given self-reported questionnaires.

RESULTS

Twenty-five public and private hospitals enrolled 278 patients. Among them, 46 had a disease flare and 41 had bowel stenoses. Bowel preparations for colonoscopy were as follows: 42% received PEG-2L, 29% received sodium picosulfate [Pico], 15% received PEG-4L, and 14% had other preparations. The preparation did not reach the Boston's score efficacy outcome in the PEG-4L group in 51.2% of the patients [p = 0.0011]. The preparation intake was complete for 59.5% in the PEG-4L group, compared with 82.9% in the PEG-2L group and 93.8% in the Pico group [p < 0.0001]. Tolerability, as assessed by the patients' VAS, was significantly better for both Pico and PEG-2L compared with PEG-4L, and better for Pico compared with PEG-2L [p = 0.008; p = 0.0003]. In multivariate analyses, low-volume preparations were independent factors of efficacy and tolerability. Adverse events occurred in 4.3% of the patients.

CONCLUSIONS

Preparations with PEG-2L and Pico were equally safe, with better efficacy and tolerability outcomes compared with PEG-4L preparations. The best efficacy/tolerance/safety profile was achieved with the Pico preparation.

The ERAS Protocol is at the forefront of the peri-operative pathway in colorectal surgery: monocentric clinical study

INTRODUCTION

Colon cancer is one of the most common neoplastic diseases, with onset in old age; the benefits of the ERAS protocol were evaluated in the peri-operative treatment of patients affected by this neoplasm.

METHODS

We studied 90 cases of colorectal neoplasia observed at the General Surgery UOC of the San Camillo de Lellis Hospital between September 2014 and April 2016, undergoing laparoscopic surgery and to which the ERAS protocol was applied; key points were the preoperative oral feeding, the epidural anesthesia, the reduced or failed hydro-electrolytic overload, the early mobilization and recovery of the feeding, the non-use of drainage. The most important parameers considered were the reduced duration of the operating hospital stay, the lower occurrence of early and distant complications.

RESULTS

85 surgical procedures were performed with laparoscopic technique (94.4%) and 5 with traditional open technique (5.6%). The conversion rate was 5.8% (5/85). 29 surgical procedures of right hemicolectomy (32.2%) and 26 of anterior resection of the rectum (28.9%) were performed; in another 29 patients (32.2%) an intervention with an open traditional technique was performed. A balanced anesthesia was performed in 41 patients (45.6%); epidural anesthesia in 32 cases (35.6%); the Tap Block in 17 subjects (18.9%). The average volume of liquid infusion was 1664cc ± 714; the average post-operative hospital stay of 4.3 ± 0.9 days.

CONCLUSIONS

The ERAS protocol reduces the duration of the post-operative hospitalization, involves a lower incidence of precocious and remote complications, in particular if associated with a minimally invasive surgical method; it is easily applicable and reproducible in a hospital environment, with a marked reduction in healthcare management costs.

Accounting for ocean connectivity and hydroclimate in fish recruitment fluctuations within transboundary metapopulations

Marine resources stewardships are progressively becoming more receptive to an effective incorporation of both ecosystem and environmental complexities into the analytical frameworks of fisheries assessment. Understanding and predicting marine fish production for spatially and demographically complex populations in changing environmental conditions is however still a difficult task. Indeed, fisheries assessment is mostly based on deterministic models that lack realistic parameterizations of the intricate biological and physical processes shaping recruitment, a cornerstone in population dynamics. We use here a large metapopulation of a harvested fish, the European hake (Merluccius merluccius), managed across transnational boundaries in the northwestern Mediterranean, to model fish recruitment dynamics in terms of physics-dependent drivers related to dispersal and survival. The connectivity among nearby subpopulations is evaluated by simulating multi-annual Lagrangian indices of larval retention, imports, and self-recruitment. Along with a proxy of the regional hydroclimate influencing early life stages survival, we then statistically determine the relative contribution of dispersal and hydroclimate for recruitment across contiguous management units. We show that inter-annual variability of recruitment is well reproduced by hydroclimatic influences and synthetic connectivity estimates. Self-recruitment (i.e., the ratio of retained locally produced larvae to the total number of incoming larvae) is the most powerful metric as it integrates the roles of retained local recruits and immigrants from surrounding subpopulations and is able to capture circulation patterns affecting recruitment at the scale of management units. We also reveal that the climatic impact on recruitment is spatially structured at regional scale due to contrasting biophysical processes not related to dispersal. Self-recruitment calculated for each management unit explains between 19% and 32.9% of the variance of recruitment variability, that is much larger than the one explained by spawning stock biomass alone, supporting an increase of consideration of connectivity processes into stocks assessment. By acknowledging the structural and ecological complexity of marine populations, this study provides the scientific basis to link spatial management and temporal assessment within large marine metapopulations. Our results suggest that fisheries management could be improved by combining information of physical oceanography (from observing systems and operational models), opening new opportunities such as the development of short-term projections and dynamic spatial management.

Abstract P2-08-34: The network metanalysis of data from PALOMA 2, MONALEESA 2, MONARCH 3, FALCON, SWOG and FACT trials: Progression free survival (PFS) benefit from first-line endocrine-based therapies in postmenopausal women with HR+ HER2- metastatic breast cancer (MBC) according to different prognostic subgroups

Background

The three classes of Cycline Dependend Kinase (CDK) 4/6 inhibitors, Palbociclib (P), Ribociclib (R) and Abemaciclib (A), in combination with non-Steroidal Aromatase Inhibitors (nSAIs) showed improvement on Progression Free Survival (PFS) in patients with HR+/HER2- MBC compared to AIs monotherapy.

Fulvestrant (F) also showed a PFS benefit over AIs in first-line setting of endocrine naive patients (pts) which was even greater in pts whithout visceral disease.

The absence of direct comparison between F and CDK 4/6 combination therapies and their less favorable toxicity profile generated great interest in the identification of a specific subgroup of pts based on clinical and pathological factors for decision-making in the use of endocrine monotherapy.

This analysis combines data from six randomized phase III trials investigating the role of endocrine-based therapies in the first-line setting of HR+/HER2- MBC to identify clinical factors in the choice among available drugs.

Methods

A Bayesian network meta-analysis was carried out for PFS; Hazard Ratio (HR) and 95% CI were reported. Potential treatment effect modifying covariates were investigated using sub-group analysis, stratifying by age, ECOG, ethnicity, prior chemotherapy or endocrine therapy exposure, measurable disease at the time of metastasis occurrence, visceral or bone only disease, time from the initial diagnosis of breast cancer to the metastasis onset. Data analysis was performed using R Statistical Software version 3.5.0

Results

In the absence of direct comparison between CDK 4/6 inhibitors + nAIs and F endocrine-based therapies, all these therapeutic options resulted in significant PFS benefit compared to nAIs monotherapy (HR: 0.74; 95% CI 0.67-0.80). However, among the three classes of CDK 4/6 inhibitors and F a significant longer PFS was observed according to some clinical-pathological factors as followed reported: from P + nAIs in “bone only” disease (HR 0.47; CI 0.25-0.86); from A + nAis in “de novo” subgroup (HR 0.60; CI 0.37-0.97), in “Asian” population (HR 0.37; CI 0.16-0.85) and “non visceral” disease (HR 0.48 CI 0.25-0.89); from R + nAIs in “de novo” subgroup (HR 0.55; CI 0.32-0.95) and in “visceral” disease (HR 0.66 CI 0.45-0.96); from all the three combination strategies (A, P and R) in “prior endocrine” exposure subgroup (HR 0.47 CI 0.25-0.87; HR 0.60 CI 0.45-0.80; HR 0.64 CI 0.41-1.0, respectively). Even though no significant PFS benefit was observed in the remaining subgroups, combined CDK 4/6 strategies appeared more effective than F according to relative HR.

Conclusions

CDK 4/6 inhibitors endocrine-based therapies as first-line treatment for postmenopausal women with HR+/HER2- MBC showed PFS improvement, regardless of prognostic subgroup and additionally advantage was emerged by indirect comparison with F. Further direct comparative studies are needed to explore greater benefits from different therapeutic options.

Citation Format: Rossi V, Giannarelli D, Berchialla P, Montemurro F, Ferretti G, Nistico' C, Vigna L, Cognetti F, Fabi A. The network metanalysis of data from PALOMA 2, MONALEESA 2, MONARCH 3, FALCON, SWOG and FACT trials: Progression free survival (PFS) benefit from first-line endocrine-based therapies in postmenopausal women with HR+ HER2- metastatic breast cancer (MBC) according to different prognostic subgroups [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 P2-08-34.

Abstract P4-13-07: SEQUERPLUS: A multicenter real practice observational study investigating the endocrine-based (E) therapies sequential approach in hormonal receptor positive (HR+) HER2 negative (-) metastatic breast cancer (MBC)

Background: Despite the sequential E therapy is recognized as the preferred approach for HR+/HER2- MBC, no data from clinical trials support the choice between the different sequential strategies.

Methods: In this retrospective study descriptive statistics are reported using the median (Interquartile range, IQR) or frequency. Progression Free Survival (PFS) curves were estimated with the Kaplan-Meier method and compared with the log-rank test. Analysis were performed by SPSS version 21.0 (SPSS Inc., Chicago, IL).

Results: From January 2006 to December 2017, 240 patients (pts) with HR+/HER2- MBC receiving at least two consecutive E therapies as first approach were selected from 12 italian cancer centers. The median age at the time of metastasis onset was 63.5 (IQR: 55-72.5) years; 184 (76.7%) pts were in menopausal status; 38 (16%) had de novo stage IV disease and the remaining 202 (84%) had recurrent BC with a median time of 78 months (5-396 months). At the beginning of MBC diagnosis, 148 (62%) pts had a single site of distant disease, 108 (45%) of whom had bone only disease and 45 (18.8%) presented visceral involvement too. The aromatase inhibitor (AI) was chosen as I-line therapy in 146 (60.9%) pts, followed by Fulvestrant (F) in 62 (25.8%) pts; the alternative I-line options were everolimus-exemestane (Eve-Exe), tamoxifene (T), Palbociclib (P)+AI and F+AI in 13 (5.4%), 14 (5.8%), 1 (0.4%) and 4 (1.7%) pts, respectively. The most favourite II-line option resulted F for 111 (46.2%) pts while the Eve-Exe combination was chosen in 70 (29.2%) pts, AI in 30 (12.5%) pts; T, AI+F, P+F and antiprogestincwere administered in 4 (1.7%), 4 (1.7%), 19 (7.9%) and 2 (0.8%) pts, respectively. For I and II-line, the AI followed by F (40%) and F followed by Eve-Exe (18%) were the most common sequential therapeutic approaches; the several alternative options were scanty used (in less than 10%). The median Progression-Free Survival (PFS) from first and second-line E therapies resulted 15.7 (95% CI 13.3-18.1) and 10.3 months (95% CI 8.7-11.9), respectively. Among 194 pts with disease progression after second-line E therapy, 87 (44.8%) received further E therapies with a median PFS 9.4 months (95% CI 7.9-10.9). The remaining 70 (29.2%) pts was treated with palliative chemotherapy. Interestingly, the median Overall Survival (OS) was even longer for pts receiving more lines of E therapies compared to the group with earlier introduction of chemotherapy (204.3 vs 92.8; p=0.007).

Finally, in the subgroup analyses a longer PFS benefit was observed in pts with disease recurrence over 12 months from initial diagnosis (38.1 vs 30.3 months p=0.04) and limited sites of disease involvement at the time of MBC diagnosis (37.6 vs 28.3 months, p=0.03)

Conclusions: The sequential use in first and second-line setting of E therapies for HR+/HER2- MBC improves median PFS up to 32.3 months. According to real practice experience the optimal sequences could be AIs followed by F and F followed by Eve-Exe. A role for these compounds should be redefined in the light of recently introduction of CDK 4/6 inhibitors in combination with AIs or F for the first or later lines.

Citation Format: Fabi A, Giannarelli D, Botticelli A, Scagnoli S, Pellegrino A, Fabbri A, Corsi D, Magri V, Pizzuti L, Paris I, Bruni V, Pace R, Lanzetta G, Stani S, Moscetti L, Marchetti P, Piesco G, Cognetti F, Rossi V. SEQUERPLUS: A multicenter real practice observational study investigating the endocrine-based (E) therapies sequential approach in hormonal receptor positive (HR+) HER2 negative (-) metastatic breast cancer (MBC) [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 P4-13-07.