Surgery for Primary Aldosteronism in France From 2010 to 2020 - Results from the French-Speaking Association of Endocrine Surgery (AFCE): Eurocrine Study Group.

OBJECTIVE: Describe the diagnostic workup and postoperative results for patients treated by adrenalectomy for primary aldosteronism in France from 2010 to 2020. BACKGROUND: Primary aldosteronism (PA) is the underlying cause of hypertension in 6% to 18% of patients. French and international guidelines recommend CT-scan and adrenal vein sampling as part of diagnostic workup to distinguish unilateral PA amenable to surgical treatment from bilateral PA that will require lifelong antialdosterone treatment.Adrenalectomy for unilateral primary aldosteronism has been associated with complete resolution of hypertension (no antihypertensive drugs and normal ambulatory blood pressure) in about one-third of patients and complete biological success in 94% of patients.These results are mainly based on retrospective studies with short follow-up and aggregated patients from various international high-volume centers. METHODS: Here we report results from the French-Speaking Association of Endocrine Surgery (AFCE) using the Eurocrine® Database. RESULTS: Over 11 years, 385 patients from 10 medical centers were eligible for analysis, accounting for >40% of adrenalectomies performed in France for primary aldosteronism over the period.Preoperative workup was consistent with guidelines for 40% of patients. Complete clinical success (CCS) at the last follow-up was achieved in 32% of patients, and complete biological success was not sufficiently assessed.For patients with 2 follow-up visits, clinical results were not persistent at 1 year for one-fifth of patients.Factors associated with CCS on multivariate analysis were body mass index, duration of hypertension, and number of antihypertensive drugs. CONCLUSIONS: These results call for an improvement in thorough preoperative workup and long-term follow-up of patients (clinical and biological) to early manage hypertension and/or PA relapse.

The biochemical composition of the actomyosin network sets the magnitude of cellular traction forces.

The regulation of cellular force production relies on the complex interplay between a well-conserved set of proteins of the cytoskeleton: actin, myosin, and α-actinin. Despite our deep knowledge of the role of these proteins in force production at the molecular scale, our understanding of the biochemical regulation of the magnitude of traction forces generated at the entire-cell level has been limited, notably by the technical challenge of measuring traction forces and the endogenous biochemical composition in the same cell. In this study, we developed an alternative Traction-Force Microscopy (TFM) assay, which used a combination of hydrogel micropatterning to define cell adhesion and shape and an intermediate fixation/immunolabeling step to characterize strain energies and the endogenous protein contents in single epithelial cells. Our results demonstrated that both the signal intensity and the area of the Focal Adhesion (FA)-associated protein vinculin showed a strong positive correlation with strain energy in mature FAs. Individual contents from actin filament and phospho-myosin displayed broader deviation in their linear relationship to strain energies. Instead, our quantitative analyzes demonstrated that their relative amount exhibited an optimum ratio of phospho-myosin to actin, allowing maximum force production by cells. By contrast, although no correlation was identified between individual α-actinin content and strain energy, the ratio of α-actinin to actin filaments was inversely related to strain energy. Hence, our results suggest that, in the cellular model studied, traction-force magnitude is dictated by the relative numbers of molecular motors and cross-linkers per actin filament, rather than the amounts of an individual component in the cytoskeletal network. This assay offers new perspectives to study in more detail the complex interplay between the endogenous biochemical composition of individual cells and the force they produce.

Comparison of treatment to improve gastrointestinal functions after colorectal surgery within enhanced recovery programmes: a systematic review and meta-analysis.

Despite a significant improvement with enhanced recovery programmes (ERP), gastro-intestinal (GI) functions that are impaired after colorectal resection and postoperative ileus (POI) remain a significant issue. In the literature, there is little evidence of the distinction between the treatment assessed within or outside ERP. The purpose was to evaluate the efficiency of treatments to reduce POI and improve GI function recovery within ERP. A search was performed in PubMed and Scopus on 20 September 2019. The studies were included if they compared the effect of the administration of a treatment aiming to treat or prevent POI or improve the early functional outcomes of colorectal surgery within an ERP. The main outcome measures were the occurrence of postoperative ileus, time to first flatus and time to first bowel movement. Treatments that were assessed at least three times were included in a meta-analysis. Among the analysed studies, 28 met the eligibility criteria. Six of them focused on chewing-gum and were only randomized controlled trials (RCT) and 8 of them focused on Alvimopan but none of them were RCT. The other measures were assessed in less than 3 studies over RCTs (n = 11) or retrospective studies (n = 2). In the meta-analysis, chewing gum had no significant effect on the endpoints and Alvimopan allowed a significant reduction of the occurrence of POI. Chewing-gum was not effective on GI function recovery in ERP but Alvimopan and the other measures were not sufficiently studies to draw conclusion. Randomised controlled trials are needed.Systematic review registration number CRD42020167339.

Individual learning curve of cytoreductive surgery for peritoneal metastasis from colorectal cancer: A process with an impact on survival.

BACKGROUND: This study aimed to assess the learning curve (LC) of cytoredutive surgery (CRS) of peritoneal metastasis (PM) from colorectal cancer (CRC). Information about learning curves is important for developing teaching tools and well-structured training programs for the implementation of this complex procedure in new healthcare centers. The aim of this study was to estimate how many procedures an inexperienced surgeon must perform (the length of the learning period) in order to demonstrate an acceptably low rate of locoregional recurrence. METHODS: All consecutive 74 patients with CRS for CRC performed by a novice surgeon between 2012 and 2017 in a tertiary cancer center were included. The learning curve was calculated by a cumulative sum control chart (CUSUM) graph. Two groups were formed based on the length of the learning period and were compared on overall and disease free survival. RESULTS: The risk of locoregional recurrence decreased after surgeons had performed 19 cases, suggesting a learning period of this length. Overall survival and postoperative morbidity were not significantly different between learning and proficiency periods. Multiple linear regression analysis showed that the learning period and peritoneal cancer index are the only factors affecting disease free survival. A second learning period was observed in cases where patient care became more complex. CONCLUSIONS: This study confirms that learning period has negative impacts on disease-free survival. An initial experience supervised in specialized centers allow to have a short learning curve for CRS for peritoneal metastases for CRC.

Stress fibres are embedded in a contractile cortical network.

Contractile actomyosin networks are responsible for the production of intracellular forces. There is increasing evidence that bundles of actin filaments form interconnected and interconvertible structures with the rest of the network. In this study, we explored the mechanical impact of these interconnections on the production and distribution of traction forces throughout the cell. By using a combination of hydrogel micropatterning, traction force microscopy and laser photoablation, we measured the relaxation of traction forces in response to local photoablations. Our experimental results and modelling of the mechanical response of the network revealed that bundles were fully embedded along their entire length in a continuous and contractile network of cortical filaments. Moreover, the propagation of the contraction of these bundles throughout the entire cell was dependent on this embedding. In addition, these bundles appeared to originate from the alignment and coalescence of thin and unattached cortical actin filaments from the surrounding mesh.

Hypertension resolution after adrenalectomy for primary hyperaldosteronism: Which is the best predictive model?

BACKGROUND: We aimed to compare the predictive performance of three distinct clinical models purported to predict the resolution of aldosteronoma-associated hypertension after adrenalectomy. METHODS: A tri-institutional database of aldosteronoma patients who underwent adrenalectomy between 2004 and 2019 was retrospectively reviewed. The three models of interest incorporate various preoperative clinical factors, such as age and sex. The predictive accuracy, as measured by area under the curve of receiver operator characteristic, was estimated. Receiver operator characteristic was evaluated across the whole cohort, then stratified by treatment location. RESULTS: A total of 200 patients were included (91 American, 109 French). The clinicodemographic variables between groups were similar; the French cohort had a lower mean body mass index (P = .02). The overall complete clinical resolution of hypertension after adrenalectomy for the entire data set was 45.5% (n = 91). The regression coefficients in the Utsumi et al (2014) Japanese model produced a superior overall area under the curve (0.78, 95% confidence interval [CI] [0.71-0.84]). This model also performed best when the cohort was stratified by treatment location (French area under the curve = 0.74, 95% CI [0.64-0.83], US area under the curve = 0.82, 95% CI [0.72-0.91]). CONCLUSION: When comparing three predictive models of aldosteronoma-associated hypertension resolution after adrenalectomy, the Utsumi et al model demonstrated the highest predictive validity across all cohorts. Counseling based on this model regarding probability of cure is recommended.

Association of Adrenal Venous Sampling With Outcomes in Primary Aldosteronism for Unilateral Adenomas.

Importance: Adrenal venous sampling is recommended prior to adrenalectomy for all patients with hyperaldosteronism; however, cross-sectional imaging resolution continues to improve, while the procedure remains invasive and technically difficult. Therefore, certain patients may benefit from advancing straight to surgery. Objective: To determine whether clinical and biochemical resolution varied for patients with primary aldosteronism with unilateral adenomas who underwent adrenal venous sampling vs those who proceeded to surgery based on imaging alone. Design, Setting, and Participants: Retrospective, international cohort study of patients treated at 3 tertiary medical centers from 2004 to 2019, with a median follow-up of approximately 6 months. A total of 217 patients were consecutively enrolled. Exclusion criteria consisted of unknown postoperative serum aldosterone level and imaging inconsistent with unilateral adenoma with a normal contralateral gland. A total of 125 patients were included in the analysis. Data were analyzed between October 2019 and July 2020. Exposures: Adrenal venous sampling performed preoperatively. Main Outcomes and Measures: The primary outcome measurements were the clinical and biochemical success rates of surgery for the cure of hyperaldosteronism secondary to aldosterone-producing adenoma. Results: A total of 125 patients were included (45 cross-sectional imaging with adrenal venous sampling and 80 imaging only). The mean (SD) age of the study participants was 50.2 (10.6) years and the cohort was 42.4% female (n = 53). Of those patients for whom race or ethnicity were reported (n = 80), most were White (72.5%). Adrenal venous sampling failure rate was 16.7%, and the imaging concordance rate was 100%. Relevant preoperative variables were similar between groups, except ambulatory systolic blood pressure, which was higher in the imaging-only group (150 mm Hg; interquartile range [IQR], 140-172 mm Hg vs 143 mm Hg, IQR, 130-158 mm Hg; P = .03). Resolution of autonomous aldosterone secretion was attained in 98.8% of imaging-only patients and 95.6% of adrenal venous sampling patients (P = .26). There was no difference in complete clinical success (43.6% [n = 34] vs 42.2% [n = 19]) or partial clinical success (47.4% [n = 37] vs 51.1% [n = 23]; P = .87) between groups. Complete biochemical resolution was similar as well (75.9% [n = 41] vs 84.4% [n = 27]; P = .35). There was no difference in clinical or biochemical cure rates when stratified by age, although complete clinical success rates downtrended in the older cohorts, and sample sizes were small. Conclusions and Relevance: Given the improved sensitivity of cross-sectional imaging in detection of adrenal tumors, adrenal venous sampling may be selectively performed in appropriate patients with clearly visualized unilateral adenomas without affecting outcomes. This may facilitate increased access to surgical cure for aldosterone-producing adenomas and will decrease the incidence of morbidities associated with the procedure.

Dissipation of contractile forces: the missing piece in cell mechanics.

Mechanical forces are key regulators of cell and tissue physiology. The basic molecular mechanism of fiber contraction by the sliding of actin filament upon myosin leading to conformational change has been known for decades. The regulation of force generation at the level of the cell, however, is still far from elucidated. Indeed, the magnitude of cell traction forces on the underlying extracellular matrix in culture is almost impossible to predict or experimentally control. The considerable variability in measurements of cell-traction forces indicates that they may not be the optimal readout to properly characterize cell contractile state and that a significant part of the contractile energy is not transferred to cell anchorage but instead is involved in actin network dynamics. Here we discuss the experimental, numerical, and biological parameters that may be responsible for the variability in traction force production. We argue that limiting these sources of variability and investigating the dissipation of mechanical work that occurs with structural rearrangements and the disengagement of force transmission is key for further understanding of cell mechanics.

The size-speed-force relationship governs migratory cell response to tumorigenic factors.

Tumor development progresses through a complex path of biomechanical changes leading first to cell growth and contraction and then cell deadhesion, scattering, and invasion. Tumorigenic factors may act specifically on one of these steps or have a wider spectrum of actions, leading to a variety of effects and thus sometimes to apparent contradictory outcomes. Here we used micropatterned lines of collagen type I/fibronectin on deformable surfaces to standardize cell behavior and measure simultaneously cell size, speed of motion and magnitude of the associated traction forces at the level of a single cell. We analyzed and compared the normal human breast cell line MCF10A in control conditions and in response to various tumorigenic factors. In all conditions, a wide range of biomechanical properties was identified. Despite this heterogeneity, normal and transformed motile cells followed a common trend whereby size and contractile forces were negatively correlated with cell speed. Some tumorigenic factors, such as activation of ErbB2 or loss of the ßsubunit of casein kinase 2, shifted the whole population toward a faster speed and lower contractility state. Treatment with transforming growth factor ß induced some cells to adopt opposing behaviors such as extremely high versus extremely low contractility. Thus tumor transformation amplified preexisting population heterogeneity and led some cells to exhibit biomechanical properties that were more extreme than those observed with normal cells.

Measurement of cell traction forces with ImageJ.

The quantification of cell traction forces requires three key steps: cell plating on a deformable substrate, measurement of substrate deformation, and the numerical estimation of the corresponding cell traction forces. The computing steps to measure gel deformation and estimate the force field have somehow limited the adoption of this method in cell biology labs. Here we propose a set of ImageJ plug-ins so that every lab equipped with a fluorescent microscope can measure cell traction forces.

Polyacrylamide hydrogel micropatterning.

This chapter describes the production of micropatterns of extracellular matrix proteins on a 2D flat polyacrylamide (PAA) gel. The technique is divided into two parts. First, micropatterns are produced on glass or directly on a photomask using deep UV. Then the micropatterns are transferred on acrylamide gel by polymerization of the gel directly on the template coverslip. This procedure is easy to perform and does not require any expensive equipment. It can be performed in no more than 2h once you get your hands on it. It combines the advantages of other existing techniques: good spatial resolution, suitable for very soft gel, no need for the use of chemical crosslinkers for attachment of the proteins to the acrylamide, no modification of the mechanical properties of the gel by the process, and suitable for multiple protein patterning. We also discuss the storage issues of such substrates and provide a brief review of other existing techniques for micropatterning on PAA.

ß1- and αv-class integrins cooperate to regulate myosin II during rigidity sensing of fibronectin-based microenvironments.

How different integrins that bind to the same type of extracellular matrix protein mediate specific functions is unclear. We report the functional analysis of ß1- and αv-class integrins expressed in pan-integrin-null fibroblasts seeded on fibronectin. Reconstitution with ß1-class integrins promotes myosin-II-independent formation of small peripheral adhesions and cell protrusions, whereas expression of αv-class integrins induces the formation of large focal adhesions. Co-expression of both integrin classes leads to full myosin activation and traction-force development on stiff fibronectin-coated substrates, with αv-class integrins accumulating in adhesion areas exposed to high traction forces. Quantitative proteomics linked αv-class integrins to a GEF-H1-RhoA pathway coupled to the formin mDia1 but not myosin II, and α5ß1 integrins to a RhoA-Rock-myosin II pathway. Our study assigns specific functions to distinct fibronectin-binding integrins, demonstrating that α5ß1integrins accomplish force generation, whereas αv-class integrins mediate the structural adaptations to forces, which cooperatively enable cells to sense the rigidity of fibronectin-based microenvironments.

Directed cytoskeleton self-organization.

The cytoskeleton architecture supports many cellular functions. Cytoskeleton networks form complex intracellular structures that vary during the cell cycle and between different cell types according to their physiological role. These structures do not emerge spontaneously. They result from the interplay between intrinsic self-organization properties and the conditions imposed by spatial boundaries. Along these boundaries, cytoskeleton filaments are anchored, repulsed, aligned, or reoriented. Such local effects can propagate alterations throughout the network and guide cytoskeleton assembly over relatively large distances. The experimental manipulation of spatial boundaries using microfabrication methods has revealed the underlying physical processes directing cytoskeleton self-organization. Here we review, step-by-step, from molecules to tissues, how the rules that govern assembly have been identified. We describe how complementary approaches, all based on controlling geometric conditions, from in vitro reconstruction to in vivo observation, shed new light on these fundamental organizing principles.

Reprogramming cell shape with laser nano-patterning.

Cell shape in vitro can be directed by geometrically defined micropatterned adhesion substrates. However conventional methods are limited by the fixed micropattern design, which cannot recapitulate the dynamic changes of the cell microenvironment. Here, we manipulate the shape of living cells in real time by using a tightly focused pulsed laser to introduce additional geometrically defined adhesion sites. The sub-micrometer resolution of the laser patterning allowed us to identify the critical distances between cell adhesion sites required for cell shape extension and contraction. This easy-to-handle method allows the precise control of specific actin-based structures that regulate cell architecture. Actin filament bundles or branched meshworks were induced, displaced or removed in response to specific dynamic modifications of the cell adhesion pattern. Isotropic branched actin meshworks could be forced to assemble new stress fibers locally and polarised in response to specific geometrical cues.