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1.
Int J Comput Assist Radiol Surg ; 18(5): 871-875, 2023 May.
Article in English | MEDLINE | ID: mdl-36449131

ABSTRACT

PURPOSE: In this work, we present a subsystem of a robotic circulating nurse, that produces recommendations for the next supplied sterile item based on incomplete requests from the sterile OR staff, the current situation, predefined knowledge and experience from previous surgeries. We describe a structure to store and query the underlying information in terms of entities and their relationships of varying strength. METHODS: For the implementation, the graph database Neo4j is used as a core component together with its querying language Cypher. We outline a specific structure of nodes and relationships, i.e., a graph. Primarily, it allows to represent entities like surgeons, surgery types and items, as well as their complex interconnectivity. In addition, it enables to match given situations and partial requests in the OR with corresponding subgraphs. The subgraphs provide suitable sterile items and allow to prioritize them according to their utilization frequency. RESULTS: The graph database was populated with existing data from 854 surgeries describing the intraoperative use of sterile items. A test scenario is evaluated in which a request for "Prolene" is made during a cholecystectomy. The software identifies a specific "Prolene" suture material as the most probable requested sterile item, because of its utilization frequency from over 95%. Other "Prolene" suture materials were used in less than 15% of the cholecystectomies. CONCLUSION: We have proposed a graph database for the selection of sterile items in the operating room. The example shows how the partial information from different sources can be easily integrated in a query, leading to an unique result. Eventually, we propose possible enhancements to further improve the quality of the recommendations. In the next step, the recommendations of the software will be evaluated in real time during surgeries.


Subject(s)
Software , Humans , Databases, Factual
2.
J Magn Reson ; 347: 107357, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36563418

ABSTRACT

The analysis of nuclear magnetic resonance (NMR) spectra to detect peaks and characterize their parameters, often referred to as deconvolution, is a crucial step in the quantification, elucidation, and verification of the structure of molecular systems. However, deconvolution of 1D NMR spectra is a challenge for both experts and machines. We propose a robust, expert-level quality deep learning-based deconvolution algorithm for 1D experimental NMR spectra. The algorithm is based on a neural network trained on synthetic spectra. Our customized pre-processing and labeling of the synthetic spectra enable the estimation of critical peak parameters. Furthermore, the neural network model transfers well to the experimental spectra and demonstrates low fitting errors and sparse peak lists in challenging scenarios such as crowded, high dynamic range, shoulder peak regions as well as broad peaks. We demonstrate in challenging spectra that the proposed algorithm is superior to expert results.

3.
Chirurgie (Heidelb) ; 93(10): 986-992, 2022 Oct.
Article in German | MEDLINE | ID: mdl-35925138

ABSTRACT

BACKGROUND: Patients with complicated appendicitis frequently develop postoperative septic complications. There are no uniform standards for the choice of perioperative antibiotic prophylaxis and the duration of postoperative antibiotic treatment. The purpose of this study was to investigate associations between microbiological samples and postoperative complications. METHODS: Patients with appendectomy and positive intraoperative swabs during 2013-2018 were included in this case-control study. Pathogen classes and their resistance patterns were evaluated in initial and follow-up swabs and compared in each of the groups with and without complications. RESULTS: A total of 870 patients underwent surgery during the period studied. Pathogen detection succeeded in 102 of 210 cases (48.6%) with suspected bacterial peritoneal contamination. Conversion from laparoscopic to open intra-abdominal perforation and the presence of an abscess were independent risk factors for wound infections in the multivariate analysis. The combination of different classes of pathogens resulted in significantly increased overall resistance to ampicillin/sulbactam in both the initial swabs (57%) and the follow-up swabs (73%). Resistant E. coli strains combined with certain anaerobes were also regularly detected in postoperative intra-abdominal abscesses. Piperacillin/tazobactam was effective against 83% of positive swabs in our resistance tests. CONCLUSION: Surgical treatment for complicated appendicitis remains the central therapeutic column. A regular review of the existing resistance patterns in perforated appendicitis can help to adjust and improve antibiotic treatment. Piperacillin/tazobactam should be used cautiously as a reserve antibiotic. A valid alternative is second or third generation cephalosporins in combination with metronidazole.


Subject(s)
Appendicitis , Ampicillin/therapeutic use , Anti-Bacterial Agents/therapeutic use , Appendicitis/complications , Case-Control Studies , Cephalosporins/therapeutic use , Escherichia coli , Humans , Metronidazole/therapeutic use , Piperacillin, Tazobactam Drug Combination/therapeutic use , Postoperative Complications , Sulbactam/therapeutic use
4.
Int J Comput Assist Radiol Surg ; 17(11): 1991-1999, 2022 Nov.
Article in English | MEDLINE | ID: mdl-35643827

ABSTRACT

PURPOSE: Surgical documentation is an important yet time-consuming necessity in clinical routine. Beside its core function to transmit information about a surgery to other medical professionals, the surgical report has gained even more significance in terms of information extraction for scientific, administrative and judicial application. A possible basis for computer aided reporting is phase detection by convolutional neural networks (CNN). In this article we propose a workflow to generate operative notes based on the output of the TeCNO CNN. METHODS: Video recordings of 15 cholecystectomies were used for inference. The annotation of TeCNO was compared to that of an expert surgeon (HE) and the algorithm based annotation of a scientist (HA). The CNN output then was used to identify aberrance from standard course as basis for the final report. Moreover, we assessed the phenomenon of 'phase flickering' as clusters of incorrectly labeled frames and evaluated its usability. RESULTS: The accordance of the HE and CNN was 79.7% and that of HA and CNN 87.0%. 'Phase flickering' indicated an aberrant course with AUCs of 0.91 and 0.89 in ROC analysis regarding number and extend of concerned frames. Finally, we created operative notes based on a standard text, deviation alerts, and manual completion by the surgeon. CONCLUSION: Computer-aided documentation is a noteworthy use case for phase recognition in standardized surgery. The analysis of phase flickering in a CNN's annotation has the potential of retrieving more information about the course of a particular procedure to complement an automated report.


Subject(s)
Cholecystectomy, Laparoscopic , Algorithms , Humans , Information Storage and Retrieval , Neural Networks, Computer , Workflow
5.
Chirurgie (Heidelb) ; 93(10): 956-965, 2022 Oct.
Article in German | MEDLINE | ID: mdl-35737019

ABSTRACT

BACKGROUND: The development of assistive technologies will become of increasing importance in the coming years and not only in surgery. The comprehensive perception of the actual situation is the basis of every autonomous action. Different sensor systems can be used for this purpose, of which video-based systems have a special potential. METHOD: Based on the available literature and on own research projects, central aspects of image-based support systems for surgery are presented. In this context, not only the potential but also the limitations of the methods are explained. RESULTS: An established application is the phase detection of surgical interventions, for which surgical videos are analyzed using neural networks. Through a time-based and transformative analysis the results of the prediction could only recently be significantly improved. Robotic camera guidance systems will also use image data to autonomously navigate laparoscopes in the near future. The reliability of the systems needs to be adapted to the high requirements in surgery by means of additional information. A comparable multimodal approach has already been implemented for navigation and localization during laparoscopic procedures. For this purpose, video data are analyzed using various methods and these data are fused with other sensor modalities. DISCUSSION: Image-based supportive methods are already available for various tasks and will become an important aspect for the surgery of the future; however, in order to be able to be reliably implemented for autonomous functions, they must be embedded in multimodal approaches in the future in order to provide the necessary security.


Subject(s)
Laparoscopes , Laparoscopy , Forecasting , Laparoscopy/methods , Neural Networks, Computer , Reproducibility of Results
6.
Chirurgie (Heidelb) ; 93(6): 566-576, 2022 Jun.
Article in German | MEDLINE | ID: mdl-35226123

ABSTRACT

Surgical interventions should ideally treat an existing disease curatively and achieve this with a low complication rate and minimal trauma. In this sense, laparoscopic cholecystectomy has become established as the recognized standard for the treatment of cholecystolithiasis. Newer procedures, such as single-port surgery or natural orifice transluminal endoscopic surgery (NOTES) have recently emerged to reduce the already low interventional trauma even further and to provide a better cosmetic outcome. With all new methods the main aim is the reduction of the transabdominal access points. Based on published results and diagnosis-related groups (DRG) data, this article examines whether this goal has been achieved, also with respect to the overall quality of treatment and the complication rates. In this context and in addition to the already mentioned approaches, robotic cholecystectomy and the reduced port approach are also considered.


Subject(s)
Cholecystectomy, Laparoscopic , Natural Orifice Endoscopic Surgery , Robotics , Cholecystectomy/methods , Cholecystectomy, Laparoscopic/adverse effects , Natural Orifice Endoscopic Surgery/methods
7.
S Afr J Psychiatr ; 27: 1587, 2021.
Article in English | MEDLINE | ID: mdl-33824756

ABSTRACT

BACKGROUND: Schizophrenia is a debilitating mental health condition affecting the lives of many South Africans. The origins of the heterogeneity in the presentation of the illness remain uncertain. AIM: This cross-sectional study performed a retrospective data analysis to determine the usefulness of digit ratio as an endophenotype in a South African schizophrenia population. SETTING: A large genetic study in a South African schizophrenia population recruited patients from services in the Western and Eastern Cape. METHODS: Complete clinical histories were captured for participants, including sets of images of the face and extremities. Software was utilised to measure the lengths of participants' digits from said images and digit ratios (2D:4D) were calculated. Descriptive analyses were performed on the ratios and statistical differences in digit ratio means were calculated between groups characterised by sex, age of onset and the presence vs absence of positive symptoms. Linear modelling was utilised to assess for correlates between 2D:4D and positive and negative symptom severity using scores obtained from the Positive and Negative Syndrome Scale (PANSS) and Scale for the Assessment of Negative Symptoms (SANS). RESULTS: 2D:4D in male participants did not significantly differ from female participants as in healthy populations. 2D:4D did not significantly correlate with the severity of positive or negative symptoms and 2D:4D means between groups did not significantly relate to age of onset. CONCLUSION: 2D:4D appears to be a possible endophenotype in schizophrenia in this population. 2D:4D, however, may not be as readily identifiable as certain minor physical anomalies and neurological soft signs significantly associated with schizophrenia in this population.

8.
BMC Oral Health ; 21(1): 117, 2021 03 12.
Article in English | MEDLINE | ID: mdl-33711986

ABSTRACT

BACKGROUND: Xerostomia is associated with several diseases and is a side effect of certain drugs, resulting from reduced saliva secretion. Often, aged and sometimes younger people suffer from (idiopathic) xerostomia. Chewing gum and sucking pastilles may relieve symptoms of xerostomia by increasing the salivary flow rate due to the mechanical effect of sucking and gustatory stimulation. Swallowing problems and the urge to cough or experiencing a tickling sensation in the throat might be alleviated through a reduction in dry mouth symptoms. We investigated whether a pastille containing four polysaccharides increased the salivary flow rate and relieved the symptoms of dry mouth. METHODS: Participating subjects with xerostomia were randomized into two equally balanced treatment groups. Subjects received the pastille on Day 1 and a control product (Parafilm®) on Day 3, or vice versa. Unstimulated saliva was collected every 2.5 min for 0-10 min. Stimulated saliva was collected after subjects sucked the pastille or the control product. The salivary flow rate was determined gravimetrically, and, in parallel, the feeling of dry mouth was assessed using a visual analog scale. Saliva surface tension was measured in pooled saliva samples (0-5 min of sampling). Additionally, in stimulated saliva from six subjects who sucked the pastille, the presence of the main ingredient-gum arabic-was examined by Raman spectroscopy. RESULTS: Chewing the pastille significantly increased the mean salivary flow rate by 8.03 g/10 min compared to the mean changes after chewing the control product (+ 3.71 g/10 min; p < 0.0001). The mean score of dry mouth was significantly alleviated by the pastille (- 19.9 ± 17.9 mm) compared to the control product (- 3.3 ± 18.1 mm). No difference between the two products was seen regarding the saliva surface tension. Gum arabic was present in the saliva of all investigated subjects for up to 10 min after sucking the pastille. CONCLUSIONS: The pastille was well tolerated and effective in increasing the salivary flow rate and reducing mouth dryness after sucking. These results were in line with the detection of the main ingredient, gum arabic, in saliva for up to 10 min after sucking the pastille. Trial registration German Register Clinical Trials (Deutsches Register Klinische Studien, DRKS) DRKS-ID: DRKS00017393, Registered 29 May 2019, https://www.drks.de/drks_web/navigate.do?navigationId=trial . HTML&TRIAL_ID = DRKS00017393.


Subject(s)
Xerostomia , Aged , Chewing Gum , Humans , Saliva , Salivation , Secretory Rate
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 4522-4526, 2020 07.
Article in English | MEDLINE | ID: mdl-33018999

ABSTRACT

Methods based exclusively on heart rate hardly allow to differentiate between physical activity, stress, relaxation, and rest, that is why an additional sensor like activity/movement sensor added for detection and classification. The response of the heart to physical activity, stress, relaxation, and no activity can be very similar. In this study, we can observe the influence of induced stress and analyze which metrics could be considered for its detection. The changes in the Root Mean Square of the Successive Differences provide us with information about physiological changes. A set of measurements collecting the RR intervals was taken. The intervals are used as a parameter to distinguish four different stages. Parameters like skin conductivity or skin temperature were not used because the main aim is to maintain a minimum number of sensors and devices and thereby to increase the wearability in the future.


Subject(s)
Electrocardiography , Exercise , Heart , Heart Rate , Rest
10.
Surg Endosc ; 34(6): 2814-2823, 2020 06.
Article in English | MEDLINE | ID: mdl-32253562

ABSTRACT

BACKGROUND: A reliable and sterile access through the intestinal wall to ease flexible endoscopic transluminal interventions is still appealing but lacks a suitable port system. METHODS: In a granted industry cooperation, we developed the MIEO-Port, a flexible three components overtube system that provides a temporary hermetic sealing of the intestinal wall to allow endoscopic disinfection and manipulation to gain access to the abdominal cavity. The port features an innovative head part which allows for coupling the port to the intestinal wall by vacuum suction and for controlled jetting the isolated intestinal surface with a disinfectant. The device was tested in vivo in 6 pigs for acute and long-term usability. All animal tests were approved by the local ethics committee. RESULTS: In the acute experiment, the port system supported sealed endoscopic mucosa resection and transluminal cholecystectomy. In the survival study on 5 animals, the MIEO-Port proved its reliability after transcolonic peritoneoscopy. In one animal, a port dislocation occurred after extensive retroperitoneal preparation, one animal revealed bacterial contamination at necropsy; however, all animals showed a favourable course over ten days and offered no signs of peritonitis or abscedation during post-mortem examination. DISCUSSION: To the best of our knowledge, the MIEO-Port system is the first device to provide a reliable and sterile flexible access to the peritoneal cavity that can be used throughout the entire gastrointestinal tract regardless of the access route and which combines hermetic sealing with local sterilization. Further studies are warranted.


Subject(s)
Endoscopic Mucosal Resection/instrumentation , Intestinal Mucosa/surgery , Laparoscopy/instrumentation , Peritoneal Cavity/surgery , Peritonitis/prevention & control , Animals , Cholecystectomy/adverse effects , Cholecystectomy/instrumentation , Cholecystectomy/methods , Endoscopic Mucosal Resection/adverse effects , Endoscopic Mucosal Resection/methods , Laparoscopy/adverse effects , Laparoscopy/methods , Models, Animal , Peritonitis/etiology , Surgical Instruments , Swine
11.
Chirurg ; 91(3): 181-189, 2020 Mar.
Article in German | MEDLINE | ID: mdl-31965199

ABSTRACT

Artificial intelligence procedures will find special fields of application also in general and visceral surgery. These will not only be limited to intraoperative surgical applications but also extend to perioperative processes, education and training as well as to future scientific developments. Major impulses are to be expected in decision support systems, cognitive collaborative interventional environments and in evidence-based knowledge acquisition models; however, the implementation into the daily practice not only requires profound insights into the field of informatics and computer science but also a comprehensive knowledge of the surgical domain. Accordingly, the future implementation of artificial intelligence in surgery requires a new culture of collaboration between surgeons and researchers/computer scientists.


Subject(s)
Digestive System Surgical Procedures , Surgeons , Artificial Intelligence , Forecasting , Humans
12.
Chirurg ; 91(1): 51-59, 2020 Jan.
Article in German | MEDLINE | ID: mdl-31654104

ABSTRACT

BACKGROUND: The digitalization process is currently on everyone's lips and sweeping changes in the field of public health and especially in surgery are to be expected within the next few years. Besides general issues, such as electronic health records and medical information systems, artificial intelligence, robotics and model-based surgery will decisively impact on the daily routine. In order to provide the necessary knowledge base, to point out related risks and chances and also to define fields of action for surgery, the German Society of Surgery commissioned a position paper on digitalization. A first appraisal in form of an online survey is the subject of this article. METHODS: This article is based on an online survey of the members of the German Society of Surgery and selected members of other related societies. The survey asked for the members' personal assessment concerning different aspects of the digitalization process and the respective state of knowledge as well as the impact on the field of surgery. RESULTS: A total of 296 members contributed to this survey. According to their assessment, digitalization in surgery is currently associated with terms such as electronic health records and medical information systems but they also assume a relevant influence on their own activities and on the fields of interventional medicine and surgery. A relevant need for improvement of the current state of knowledge was highlighted, not only for general aspects of digitalization but also for surgically relevant issues in particular. The vast majority of interviewed members saw digitalization more as a chance for improvement than as a risk factor. CONCLUSION: According to the views of interviewed members of the German Society of Surgery the process of digital transformation will significantly impact the field of surgery. All those involved should feel responsible to contribute to and guide this process in order to maintain the surgically inherent requirements and to protect patient safety. The position paper on digitalization can serve as a basis and should define concrete recommendations for action. In the sense of an academic approach the new possibilities should be critically evaluated with respect to suitability and should be exclusively confined to applications that are beneficial to ourselves and to our patients.


Subject(s)
Artificial Intelligence , Electronic Health Records , General Surgery , Robotic Surgical Procedures , Attitude of Health Personnel , General Surgery/trends , Humans , Risk Factors , Surgeons , Surveys and Questionnaires
13.
Chirurg ; 90(6): 470-477, 2019 Jun.
Article in German | MEDLINE | ID: mdl-30758596

ABSTRACT

BACKGROUND: The "magic triangle" in surgery and other disciplines consists of the demand for increasingly gentler forms of treatment, simultaneous cost reduction and the fundamental primacy of improving the quality of results. The digitalization of medicine offers a promising opportunity to do justice to this, also in the sense of "Surgery 4.0". The aim is to create a cognitive, collaborative diagnostics and treatment environment to support the surgeon. METHODS: In the sense of a "theory building" for analysis and planning, process modeling is the cornerstone for modern treatment planning. The main distinction is made between the patient model and the treatment model. The course of the actual surgical treatment can also be modeled: in principle it is possible to describe the course of an operation in such fine detail that the surgical procedure can be mapped and reproduced down to each single step, such as a single implementation of forceps. Basically, this has already been achieved. So-called neural networks also open up completely new forms of knowledge acquisition, machine learning and flexible reaction to nearly all conceivable possibilities in highly complex processes. CONCLUSION: "Digitalization" is a necessary development in surgery. It offers not only countless possibilities to support the surgeon in the field of activity but also the chance of more precise data acquisition with respect to academic surgery. Modeling is an indispensable part of this and must be rigorously implemented and further developed.


Subject(s)
Neural Networks, Computer , Surgical Procedures, Operative , Humans , Models, Theoretical
15.
Chirurg ; 89(10): 760-768, 2018 Oct.
Article in German | MEDLINE | ID: mdl-30132168

ABSTRACT

BACKGROUND: Digitalization in surgery is gaining attention in the surgical community, with robotics and augmented reality as key issues. ROBOTICS: The term surgical robot is basically not adequate to describe currently available telesupport and manipulation systems. These are passive tools which have to be activated by the surgeon and only provide relatively low levels of active support. Accordingly, justification of use is currently difficult with respect to the cost-benefit relationship. A real breakthrough will be achieved by upgrading them into genuine intelligent and collaborative support systems and justify the term as the true meaning of robotics. AUGMENTED REALITY (AR): Augmented or enriched reality improves or facilitates normal sensory perception by the integration of additional information of a different nature. Intuitive perception of the surgical site would have the potential to revolutionize surgery, but prior to clinical use, the matching of the real and the virtual world still has to be optimized (referencing); however, AR is now already a valuable tool for training and simulation as well as workflow support in the operating room (OR). CRITICAL COMMENT AND PERSPECTIVES: The promising new technological development towards the future cooperative surgical OR environment, including both robotic and AR modules, will have a significant impact on surgery, even in the mid-term. Decisive for this is that surgeons actively take part in the evaluation of this process to ensure that future "intelligent" tools will remain mere assistant or supporting systems.


Subject(s)
Robotics , Surgical Procedures, Operative , Forecasting , Humans , Surgical Procedures, Operative/trends , User-Computer Interface
16.
Br J Surg ; 105(7): 784-796, 2018 06.
Article in English | MEDLINE | ID: mdl-29088493

ABSTRACT

BACKGROUND: It is not clear whether resection of the primary tumour (when there are metastases) alters survival and/or whether resection is associated with increased morbidity. This systematic review and meta-analysis assessed the prognostic value of primary tumour resection in patients presenting with metastatic colorectal cancer. METHODS: A systematic review of MEDLINE/PubMed was performed on 12 March 2016, with no language or date restrictions, for studies comparing primary tumour resection versus conservative treatment without primary tumour resection for metastatic colorectal cancer. The quality of the studies was assessed using the MINORS and STROBE criteria. Differences in survival, morbidity and mortality between groups were estimated using random-effects meta-analysis. RESULTS: Of 37 412 initially screened articles, 56 retrospective studies with 148 151 patients met the inclusion criteria. Primary tumour resection led to an improvement in overall survival of 7·76 (95 per cent c.i. 5·96 to 9·56) months (risk ratio (RR) for overall survival 0·50, 95 per cent c.i. 0·47 to 0·53), but did not significantly reduce the risk of obstruction (RR 0·50, 95 per cent c.i. 0·16 to 1·53) or bleeding (RR 1·19, 0·48 to 2·97). Neither was the morbidity risk altered (RR 1·14, 0·77 to 1·68). Heterogeneity between the studies was high, with a calculated I2 of more than 50 per cent for most outcomes. CONCLUSION: Primary tumour resection may provide a modest survival advantage in patients presenting with metastatic colorectal cancer.


Subject(s)
Colorectal Neoplasms/secondary , Colorectal Neoplasms/surgery , Colorectal Neoplasms/complications , Colorectal Neoplasms/mortality , Combined Modality Therapy , Gastrointestinal Hemorrhage/etiology , Gastrointestinal Hemorrhage/prevention & control , Humans , Intestinal Obstruction/etiology , Intestinal Obstruction/prevention & control , Postoperative Complications/mortality , Survival Analysis
17.
Chirurg ; 88(3): 196-203, 2017 Mar.
Article in German | MEDLINE | ID: mdl-28054111

ABSTRACT

Esophageal diverticula are comparatively rare. The majority are Zenker's diverticula but parabronchial and epiphrenic diverticula can also occur. Parabronchial diverticula are of low clinical relevance, whereas Zenker's and epiphrenic diverticula both belong to the group of pulsion diverticula and can become clinically apparent by dysphagia and regurgitation. Approximately 100 years after the first surgical treatment, peroral approaches (e.g. stapler dissection and flexible endoscopic diverticulotomy) have now achieved a certain level of importance. Both approaches are less invasive than the open approach but are evidently more prone to recurrences. Accordingly, traditional open diverticulectomy with cervical myotomy should be recommended to patients with a reasonable life expectancy and an acceptable operative risk. This holds particularly true for Brombart stages I-III of the disease, as complete myotomy cannot be achieved via the peroral access. The classical surgical treatment of epiphrenic diverticula is open or laparoscopic/thoracoscopic diverticulectomy with distal myotomy, mostly combined with an anterior partial fundoplication; however, the leakage rate is high and several alternative options are currently being evaluated.


Subject(s)
Diverticulum, Esophageal/surgery , Esophageal Sphincter, Lower/surgery , Esophagoscopy/methods , Fundoplication/methods , Laparoscopy/methods , Thoracoscopy/methods , Combined Modality Therapy , Diverticulum, Esophageal/diagnosis , Humans , Postoperative Complications/diagnosis , Postoperative Complications/etiology , Postoperative Complications/surgery , Recurrence , Reoperation , Zenker Diverticulum/diagnosis , Zenker Diverticulum/surgery
18.
Oncogene ; 36(2): 208-218, 2017 01 12.
Article in English | MEDLINE | ID: mdl-27270435

ABSTRACT

R-spondin1 is a secreted regulator of WNT signaling, involved in both embryonic development and homeostasis of adult organs. It can have a dual role, acting either as a mitogen or as a tumor suppressor. During ovarian development, Rspo1 is a key factor required for sex determination and differentiation of the follicular cell progenitors, but is downregulated after birth. In human, increased RSPO1 expression is associated with ovarian carcinomas, but it is not clear whether it is a cause or a consequence of the tumorigenic process. To address the role of Rspo1 expression in adult ovaries, we generated an Rspo1 gain-of-function mouse model. Females were hypofertile and exhibited various ovarian defects, ranging from cysts to ovarian tumors. Detailed phenotypical characterization showed anomalies in the ovulation process. Although follicles responded to initial follicle-stimulating hormone stimulation and developed normally until the pre-ovulatory stage, they did not progress any further. Although non-ovulated oocytes degenerated, the surrounding follicular cells did not begin atresia. RSPO1-induced expression not only promotes canonical WNT signaling but also alters granulosa cell fate decisions by maintaining epithelial-like traits in these cells. This prevents follicle cells from undergoing apoptosis, leading to the accumulation of granulosa cell tumors that reactivates the epithelial program from their progenitors. Taken together, our data demonstrate that activation of RSPO1 is sufficient in promoting ovarian tumors and thus supports a direct involvement of this gene in the commencement of ovarian cancers.


Subject(s)
Cell Transformation, Neoplastic/metabolism , Granulosa Cells/metabolism , Ovarian Neoplasms/pathology , Thrombospondins/genetics , Animals , Cell Transformation, Neoplastic/pathology , Female , Gene Expression Regulation, Developmental , Granulosa Cells/pathology , Mice , Ovarian Neoplasms/metabolism , Ovarian Neoplasms/veterinary , Thrombospondins/metabolism , Up-Regulation , Wnt Signaling Pathway
19.
Skin Res Technol ; 23(1): 3-12, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27503009

ABSTRACT

BACKGROUND: The healing of wounds has always provided challenges for the medical community whether chronic or acute. Understanding the processes which enable wounds to heal is primarily carried out by the use of models, in vitro, animal and human. It is generally accepted that the use of human models offers the best opportunity to understand the factors that influence wound healing as well as to evaluate efficacy of treatments applied to wounds. OBJECTIVES: The objective of this article is to provide an overview of the different methodologies that are currently used to experimentally induce wounds of various depths in human volunteers and examines the information that may be gained from them. METHODS: There is a number of human volunteer healing models available varying in their invasiveness to reflect the different possible depth levels of wounds. RESULTS: Currently available wound healing models include sequential tape stripping, suction blister, abrasion, laser, dermatome, and biopsy techniques. The various techniques can be utilized to induce wounds of variable depth, from removing solely the stratum corneum barrier, the epidermis to even split-thickness or full thickness wounds. CONCLUSION: Depending on the study objective, a number of models exist to study wound healing in humans. These models provide efficient and reliable results to evaluate treatment modalities.


Subject(s)
Lacerations/physiopathology , Skin/injuries , Skin/physiopathology , Wound Healing/physiology , Wounds, Penetrating/physiopathology , Biopsy/methods , Dermabrasion/methods , Humans , Surgical Tape
20.
Chirurg ; 87(12): 1002-1007, 2016 Dec.
Article in German | MEDLINE | ID: mdl-27844111

ABSTRACT

BACKGROUND: A comprehensive surveillance and control system integrating all devices and functions is a precondition for realization of the operating room of the future. STATE OF THE ART: Multiple proprietary integrated operation room systems are currently available with a central user interface; however, they only cover a relatively small part of all functionalities. INNOVATIVE APPROACHES: Internationally, there are at least three different initiatives to promote a comprehensive systems integration and networking in the operating room: the Japanese smart cyber operating theater (SCOT), the American medical device plug-and-play interoperability program (MDPnP) and the German secure and dynamic networking in operating room and hospital (OR.NET) project supported by the Federal Ministry of Education and Research. PRELIMINARY RESULTS: Within the framework of the internationally advanced OR.NET project, prototype solution approaches were realized, which make short-term and mid-term comprehensive data retrieval systems probable. An active and even autonomous control of the medical devices by the surveillance and control system (closed loop) is expected only in the long run due to strict regulatory barriers.


Subject(s)
Interdisciplinary Communication , Intersectoral Collaboration , Operating Rooms/organization & administration , Germany , Humans , Robotic Surgical Procedures , Safety Management/organization & administration , Surgical Equipment , Systems Integration , User-Computer Interface
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