Bilateral Concurrent Benign Phyllodes Tumor in a 43-Year-Old Female: A Case Report.

Phyllodes tumor is considered a rare form of breast tissue neoplasm that presents as a rapidly growing painless mass. This neoplasm is classified as benign, borderline, or malignant and standard treatment consists of surgical excision with clear margins. The vast majority of reported cases have described the unilateral presentation of this tumor, making bilateral presentation a rare find. Our case describes a 43-year-old Hispanic woman with a history of fibroadenomas who was found to have concurrent benign bilateral phyllodes tumors

Proteinuria converts hepatic heparan sulfate to an effective proprotein convertase subtilisin kexin type 9 enzyme binding partner:a historical appraisal of its origins and conceptual evolution

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Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Remodelage des heparanes sulfate : caractérisation fonctionnelle et structurale de l'endosulfatase humaine HSulf-2

Heparan Sulfate (HS) are complex polysaccharides involved in many biological processes. The structure of HS is regulated at the cell surface by unique extracellular endosulfatases, the Sulfs. Sulfs dramatically change HS functional properties, thereby being implicated in many physiopathological processes including cancer. Sulfs features two domains: a catalytic domain (CAT) that comprises the active site, and an hydrophilic basic domain (HD) responsible for HS binding. The aim of my PhD project is to characterize the structural and the functional properties of the human for HSulf-2, which remains poorly understood. In this context, we have first studied the enzyme/substrate recognition mechanisms. We identified two novel HS binding motifs on these enzymes implicated in their activity. In addition, using natural and synthetic oligosaccharides, we demonstrated that the HD is not essential for HS recognition, but is directs the processive and orientated desulfation of the polysaccharide. Moreover, we showed that a tetrasaccharide is the minimal oligosaccharide size required for HSulf-2 activity. Our results enabled us to propose a new model depicting the desulfation process of HS by the Sulfs. Second, we have shown that HSulf-2 is a proteoglycan, given that it harbors a unique PTM (Chondroitin Sulfate, CS chain) on its HD domain. This chain decreases enzyme activity and HS binding in vitro. In the tumoral microenvironment, using a murine orthotropic mammary tumor model, we showed that the CS chain is lost by proteolytic processing, leading to the activation of HSulf-2, and the promotion of tumor growth, vascularization and metastasis. Finally, we have undertaken the structural characterization of the Sulfs. For this, we decided to study separately the two domains found in these enzymes (CAT and HD). Crystallogenesis assays were undertaken for the CAT domain to solve its structure by X-ray crystallography, but were unsuccessful. Regarding the HD, we set up a protocol of production and purification of recombinant HD and we initiated NMR studies and other biophysics analyses in order to structurally characterize the domain and to identify the HS binding sites. Our preliminary results suggest that the HD is an unstructured domain, except for its N- and C-terminal parts. Overall, our data provide significant insights into this critical regulatory step of HS function.Les Héparanes Sulfates (HS) sont de polysaccharides complexes impliqués dans de nombreux processus biologiques. La structure des HS est contrôlée à la surface cellulaire par une famille particulière d‟endosulfatases extracellulaires, les Sulfs. Les Sulfs modifient dramatiquement les propriétés fonctionnelles des HS et sont impliqués dans de nombreux processus physiopathologiques, notamment le cancer. Ces enzymes se composent de deux domaines: un domaine catalytique (CAT) contenant le site actif et un domaine basique hydrophile (HD) responsable de la liaison aux HS. Le but de mon projet de thèse est de caractériser les propriétés structurales et fonctionnelles de la forme humaine HSulf-2, qui demeure à ce jour très mal connues. Dans ce cadre, nous avons tout d‟abord étudié les mécanismes de reconnaissance enzyme/substrat et caractérisé deux nouveaux motifs de reconnaissance des HS sur ces enzymes, responsable de leur activité. En utilisant des oligosaccharides naturels et synthétiques, nous avons aussi démontré que le domaine HD n'est pas essentiel pour la reconnaissance des HS, mais est permet une désulfatation processive et orientée du polysaccharide. De plus, nous avons identifié un tétrasaccharide comme étant la taille oligosaccharidique minimale requise pour l'activité de HSulf-2. Nos résultats nous ont permis de proposer un nouveau modèle décrivant le processus de désulfatation du HS par HSulf-2. D'autre part, nous avons montré que HSulf-2 est un protéoglycane, car il contient une modification post-traductionnelle unique (chaîne CS de Chondoitin Sulfate) sur son domaine HD. Cette chaîne diminue l'activité enzymatique et la liaison aux HS in vitro. Dans le microenvironnement tumoral, en utilisant un modèle de tumeur mammaire orthotopique murin, nous avons montré que la chaîne CS est libérée par protéolyse, conduisant à l'activation de HSulf-2, augmentant la capacité des tumeurs à se développer et à se transformer en métastase. Finalement, nous avons réalisé une étude structurale des Sulfs. Nous avons choisi d‟étudier séparément les deux domaines (CAT et HD). Des essais de cristallogenèse ont été menés pour le domaine CAT afin de résoudre sa structure par cristallographie aux rayons X, mais n‟ont pu aboutir. En ce qui concerne le HD, nous avons mis en place un protocole de production et de purification de HD d‟une manière recombinante et nous avons initiés une étude par RMN ainsi que d'autres techniques biophysiques afin de caractériser structuralement le domaine et d'identifier les sites de liaison aux HS. Nos résultats préliminaires suggèrent que la HD est un domaine non structuré, à l'exception de ses parties N- et C-terminales. L‟ensemble de ces travaux devrait nous permettre de mieux comprendre ces importants mécanismes de régulation des HS et de d‟envisager de nouvelles stratégies anticancéreuses ciblant les Sulfs

Remodelage des heparanes sulfate : caractérisation fonctionnelle et structurale de l'endosulfatase humaine HSulf-2

Heparan Sulfate (HS) are complex polysaccharides involved in many biological processes. The structure of HS is regulated at the cell surface by unique extracellular endosulfatases, the Sulfs. Sulfs dramatically change HS functional properties, thereby being implicated in many physiopathological processes including cancer. Sulfs features two domains: a catalytic domain (CAT) that comprises the active site, and an hydrophilic basic domain (HD) responsible for HS binding. The aim of my PhD project is to characterize the structural and the functional properties of the human for HSulf-2, which remains poorly understood. In this context, we have first studied the enzyme/substrate recognition mechanisms. We identified two novel HS binding motifs on these enzymes implicated in their activity. In addition, using natural and synthetic oligosaccharides, we demonstrated that the HD is not essential for HS recognition, but is directs the processive and orientated desulfation of the polysaccharide. Moreover, we showed that a tetrasaccharide is the minimal oligosaccharide size required for HSulf-2 activity. Our results enabled us to propose a new model depicting the desulfation process of HS by the Sulfs. Second, we have shown that HSulf-2 is a proteoglycan, given that it harbors a unique PTM (Chondroitin Sulfate, CS chain) on its HD domain. This chain decreases enzyme activity and HS binding in vitro. In the tumoral microenvironment, using a murine orthotropic mammary tumor model, we showed that the CS chain is lost by proteolytic processing, leading to the activation of HSulf-2, and the promotion of tumor growth, vascularization and metastasis. Finally, we have undertaken the structural characterization of the Sulfs. For this, we decided to study separately the two domains found in these enzymes (CAT and HD). Crystallogenesis assays were undertaken for the CAT domain to solve its structure by X-ray crystallography, but were unsuccessful. Regarding the HD, we set up a protocol of production and purification of recombinant HD and we initiated NMR studies and other biophysics analyses in order to structurally characterize the domain and to identify the HS binding sites. Our preliminary results suggest that the HD is an unstructured domain, except for its N- and C-terminal parts. Overall, our data provide significant insights into this critical regulatory step of HS function.Les Héparanes Sulfates (HS) sont de polysaccharides complexes impliqués dans de nombreux processus biologiques. La structure des HS est contrôlée à la surface cellulaire par une famille particulière d‟endosulfatases extracellulaires, les Sulfs. Les Sulfs modifient dramatiquement les propriétés fonctionnelles des HS et sont impliqués dans de nombreux processus physiopathologiques, notamment le cancer. Ces enzymes se composent de deux domaines: un domaine catalytique (CAT) contenant le site actif et un domaine basique hydrophile (HD) responsable de la liaison aux HS. Le but de mon projet de thèse est de caractériser les propriétés structurales et fonctionnelles de la forme humaine HSulf-2, qui demeure à ce jour très mal connues. Dans ce cadre, nous avons tout d‟abord étudié les mécanismes de reconnaissance enzyme/substrat et caractérisé deux nouveaux motifs de reconnaissance des HS sur ces enzymes, responsable de leur activité. En utilisant des oligosaccharides naturels et synthétiques, nous avons aussi démontré que le domaine HD n'est pas essentiel pour la reconnaissance des HS, mais est permet une désulfatation processive et orientée du polysaccharide. De plus, nous avons identifié un tétrasaccharide comme étant la taille oligosaccharidique minimale requise pour l'activité de HSulf-2. Nos résultats nous ont permis de proposer un nouveau modèle décrivant le processus de désulfatation du HS par HSulf-2. D'autre part, nous avons montré que HSulf-2 est un protéoglycane, car il contient une modification post-traductionnelle unique (chaîne CS de Chondoitin Sulfate) sur son domaine HD. Cette chaîne diminue l'activité enzymatique et la liaison aux HS in vitro. Dans le microenvironnement tumoral, en utilisant un modèle de tumeur mammaire orthotopique murin, nous avons montré que la chaîne CS est libérée par protéolyse, conduisant à l'activation de HSulf-2, augmentant la capacité des tumeurs à se développer et à se transformer en métastase. Finalement, nous avons réalisé une étude structurale des Sulfs. Nous avons choisi d‟étudier séparément les deux domaines (CAT et HD). Des essais de cristallogenèse ont été menés pour le domaine CAT afin de résoudre sa structure par cristallographie aux rayons X, mais n‟ont pu aboutir. En ce qui concerne le HD, nous avons mis en place un protocole de production et de purification de HD d‟une manière recombinante et nous avons initiés une étude par RMN ainsi que d'autres techniques biophysiques afin de caractériser structuralement le domaine et d'identifier les sites de liaison aux HS. Nos résultats préliminaires suggèrent que la HD est un domaine non structuré, à l'exception de ses parties N- et C-terminales. L‟ensemble de ces travaux devrait nous permettre de mieux comprendre ces importants mécanismes de régulation des HS et de d‟envisager de nouvelles stratégies anticancéreuses ciblant les Sulfs

Une palmitoylation de CDC42 causée par une mutation déclenche un syndrome auto-inflammatoire sévère

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HS and Inflammation: A Potential Playground for the Sulfs?

International audienceHeparan sulfate (HS) is a complex polysaccharide abundantly found in extracellular matrices and cell surfaces. HS participates in major cellular processes, through its ability to bind and modulate a wide array of signaling proteins. HS/ligand interactions involve saccharide domains of specific sulfation pattern. Assembly of such domains is orchestrated by a complex biosynthesis machinery and their structure is further regulated at the cell surface by post-synthetic modifying enzymes. Amongst them, extracellular sulfatases of the Sulf family catalyze the selective removal of 6-O-sulfate groups, which participate in the binding of many proteins. As such, increasing interest arose on the regulation of HS biological properties by the Sulfs. However, studies of the Sulfs have so far been essentially restricted to the fields of development and tumor progression. The aim of this review is to survey recent data of the literature on the still poorly documented role of the Sulfs during inflammation, and to widen the perspectives for the study of this intriguing regulatory mechanism toward new physiopathological processes

The "in and out" of glucosamine 6-O-sulfation: the 6th sense of heparan sulfate.

International audienceThe biological properties of Heparan sulfate (HS) polysaccharides essentially rely on their ability to bind and modulate a multitude of protein ligands. These interactions involve internal oligosaccharide sequences defined by their sulfation patterns. Amongst these, the 6-O-sulfation of HS contributes significantly to the polysaccharide structural diversity and is critically involved in the binding of many proteins. HS 6-O-sulfation is catalyzed by 6-O-sulfotransferases (6OSTs) during biosynthesis, and it is further modified by the post-synthetic action of 6-O-endosulfatases (Sulfs), two enzyme families that remain poorly characterized. The aim of the present review is to summarize the contribution of 6-O-sulfates in HS structure/function relationships and to discuss the present knowledge on the complex mechanisms regulating HS 6-O-sulfation

Mass spectrometry analysis of the human endosulfatase Hsulf-2

The human 6-O-endosulfatases HSulf-1 and -2 catalyze the region-selective hydrolysis of the 6-O-sulfate group of the glucosamine residues within sulfated domains of heparan sulfate, thereby ensuring a unique and original post-biosynthetic modification of the cell surface proteoglycans. While numerous studies point out the role of HSulf-2 in crucial physiological processes as well as in pathological conditions particularly in cancer, its structural organization in two chains and its functional properties remain poorly understood. In this study, we report the first characterization by mass spectrometry (MS) of HSulf-2. An average molecular weight of 133,115 Da was determined for the whole enzyme by MALDI-TOF MS, i.e. higher than the naked amino acid backbone (98,170 Da), highlighting a significant contribution of post-translational modifications. The HSulf-2 protein sequence was determined by Nano-LC-MS/MS, leading to 63% coverage and indicating at least four N-glycosylation sites at Asn 108, 147, 174 and 217. These results provide a platform for further structural investigations of the HSulf enzymes, aiming at deciphering the role of each chain in the substrate binding and specificities and in the catalytic activities. Keywords: HSulf-2, 6-O-Endosulfatase, Sulfatase, Heparan sulfate, Formylglycine, Mass spectrometr

A Hybrid Mesh, Ad Hoc, and Sensor Network for Forest Fire Management

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