691 research outputs found
Hybrid fiber grating cavity for multi-parametric sensing.
We propose an all-fiber hybrid cavity involving two unbalanced uniform fiber Bragg gratings (FBGs) written at both sides of a tilted FBG (TFBG) to form an all-fiber interferometer. This configuration provides a wavelength gated reflection signal with interference fringes depending on the cavity features modulated by spectral dips associated to the wavelength dependent optical losses due to cladding mode coupling occurring along the TFBG. Such a robust structure preserves the advantages of uniform FBGs in terms of interrogation methods and allows the possibility of simultaneous physical and chemical sensing
Editorial: New technological frontiers in the diagnosis and treatment of gastrointestinal cancers
Pancreaticoduodenectomy model demonstrates a fundamental role of dysfunctional β cells in predicting diabetes
BACKGROUND. The appearance of hyperglycemia is due to insulin resistance, functional deficits in the secretion of insulin, and a reduction of β cell mass. There is a long-standing debate as to the relative contribution of these factors to clinically manifesting β cell dysfunction. The aim of this study was to verify the acute effect of one of these factors, the reduction of β cell mass, on the subsequent development of hyperglycemia. METHODS. To pursue this aim, nondiabetic patients, scheduled for identical pancreaticoduodenectomy surgery, underwent oral glucose tolerance tests (OGTT) and hyperglycemic clamp (HC) procedures, followed by arginine stimulation before and after surgery. Based on postsurgery OGTT, subjects were divided into 3 groups depending on glucose tolerance: normal glucose tolerance (post-NGT), impaired glucose tolerance (post-IGT), or having diabetes mellitus (post-DM). RESULTS. At baseline, the 3 groups showed similar fasting glucose and insulin levels; however, examining the various parameters, we found that reduced first-phase insulin secretion, reduced glucose sensitivity, and rate sensitivity were predictors of eventual postsurgery development of IGT and diabetes. CONCLUSION. Despite comparable functional mass and fasting glucose and insulin levels at baseline and the very same 50% mass reduction, only reduced first-phase insulin secretion and glucose sensitivity predicted the appearance of hyperglycemia. These functional alterations could be pivotal to the pathogenesis of type 2 diabetes (T2DM)
Gallstone Ileus: An Unusual Cause of Small Bowel Obstruction: A Case Report
Gallstone ileus represents a rare complication of chronic cholelithiasis
and is considered a mechanical bowel obstruction caused by one or more
gallstones becoming lodged in the gastrointestinal tract. The etiology of
gallstone ileus is due to the transit of a calculum through a cholecystointestinal
fistula. In all cases of acute abdomen, diagnostic suspicion and appropriate first
surgical treatment are important for an adequate clinical progression due to
its low incidence. On other hand, due to the high incidence of gallstones, such
situations may arise in ordinary clinical practices, and clinicians should evaluate
gallstone ileus as a possible cause of bowel obstruction. However, because of
the poor general health of ileus patients, choosing an appropriate treatment is
challenging, and clinicians must make a decision on which surgery to perform.
We present a case of an elderly patient who presented to our emergency
department with gallstone ileus that received a prompt diagnosis and urgent
surgical resolution
Unusual focal keratin expression in plexiform angiomyxoid myofibroblastic tumor: A case report and review of the literature
Background: Plexiform angiomyxoid myofibroblastic tumor (PAMT), also known as plexiform fibromyxoma, is a rare distinctive benign intramural tumor, typical of gastric antrum, commonly causing mucosal ulceration with upper gastrointestinal bleeding and anemia, effectively treated by complete surgical resection usually accomplished by distal gastrectomy. Methods and Results: We herein report a 47-year-old man presenting with a syncopal episode, regurgitation and epigastric discomfort, bearing a gastric antral myxoid plexiform tumor positive for \u3b1-smooth muscle actin, vimentin and, partially, for caldesmon, desmin, and CD10; CD117, DOG1, CD34, S100, CAM5.2, CK20, CK7, EMA, p53, CDX2, chromogranin A, synaptophysin, anaplastic lymphoma kinase, Melan-A, and HMB-45 were all negative. All these features are typical of PAMT. Of note, focal positivity for AE1/AE3 and pan-CK KL1 was also present. Conclusions: The finding of a focal keratin expression in PAMT contributes to enlarge the immunophenotypic spectrum of this tumor type and is relevant for avoiding presurgical misdiagnoses which could ultimately lead to inappropriate overtreatment of patients with PAMT
Preserving privacy in surgical video analysis using a deep learning classifier to identify out-of-body scenes in endoscopic videos
Surgical video analysis facilitates education and research. However, video recordings of endoscopic surgeries can contain privacy-sensitive information, especially if the endoscopic camera is moved out of the body of patients and out-of-body scenes are recorded. Therefore, identification of out-of-body scenes in endoscopic videos is of major importance to preserve the privacy of patients and operating room staff. This study developed and validated a deep learning model for the identification of out-of-body images in endoscopic videos. The model was trained and evaluated on an internal dataset of 12 different types of laparoscopic and robotic surgeries and was externally validated on two independent multicentric test datasets of laparoscopic gastric bypass and cholecystectomy surgeries. Model performance was evaluated compared to human ground truth annotations measuring the receiver operating characteristic area under the curve (ROC AUC). The internal dataset consisting of 356,267 images from 48 videos and the two multicentric test datasets consisting of 54,385 and 58,349 images from 10 and 20 videos, respectively, were annotated. The model identified out-of-body images with 99.97% ROC AUC on the internal test dataset. Mean +/- standard deviation ROC AUC on the multicentric gastric bypass dataset was 99.94 +/- 0.07% and 99.71 +/- 0.40% on the multicentric cholecystectomy dataset, respectively. The model can reliably identify out-of-body images in endoscopic videos and is publicly shared. This facilitates privacy preservation in surgical video analysis
Role of radiomics in predicting lymph node metastasis in gastric cancer: a systematic review
IntroductionGastric cancer (GC) is an aggressive and clinically heterogeneous tumor, and better risk stratification of lymph node metastasis (LNM) could lead to personalized treatments. The role of radiomics in the prediction of nodal involvement in GC has not yet been systematically assessed. This study aims to assess the role of radiomics in the prediction of LNM in GC.MethodsA PubMed/MEDLINE systematic review was conducted to assess the role of radiomics in LNM. The inclusion criteria were as follows: i. original articles, ii. articles on radiomics, and iii. articles on LNM prediction in GC. All articles were selected and analyzed by a multidisciplinary board of two radiation oncologists and one surgeon, under the supervision of one radiation oncologist, one surgeon, and one medical oncologist.ResultsA total of 171 studies were obtained using the search strategy mentioned on PubMed. After the complete selection process, a total of 20 papers were considered eligible for the analysis of the results. Radiomics methods were applied in GC to assess the LNM risk. The number of patients, imaging modalities, type of predictive models, number of radiomics features, TRIPOD classification, and performances of the models were reported.ConclusionsRadiomics seems to be a promising approach for evaluating the risk of LNM in GC. Further and larger studies are required to evaluate the clinical impact of the inclusion of radiomics in a comprehensive decision support system (DSS) for GC
The Role of Staging Laparoscopy for Gastric Cancer Patients: Current Evidence and Future Perspectives
A significant proportion of patients diagnosed with gastric cancer is discovered with peritoneal metastases at laparotomy. Despite the continuous improvement in the performance of radiological imaging, the preoperative recognition of such an advanced disease is still challenging during the diagnostic work-up, since the sensitivity of CT scans to peritoneal carcinomatosis is not always adequate. Staging laparoscopy offers the chance to significantly increase the rate of promptly diagnosed peritoneal metastases, thus reducing the number of unnecessary laparotomies and modifying the initial treatment strategy of gastric cancer. The aim of this review was to provide a comprehensive summary of the current literature regarding the role of staging laparoscopy in the management of gastric cancer. Indications, techniques, accuracy, advantages, and limitations of staging laparoscopy and peritoneal cytology were discussed. Furthermore, a focus on current evidence regarding the application of artificial intelligence and image-guided surgery in staging laparoscopy was included in order to provide a picture of the future perspectives of this technique and its integration with modern tools in the preoperative management of gastric cancer
Advancing Diabetes Research: a novel islet isolation method from living donors.
Pancreatic islet isolation is critical for type 2 diabetes research. Although -omics approaches have shed light on islet molecular profiles, inconsistencies persist; on the other side, functional studies are essential, but they require reliable and standardized isolation methods. Here, we propose a simplified protocol applied to very small-sized samples collected from partially pancreatecto-mized living donors. Islet isolation was performed digesting tissue specimens collected during surgery within a collagenase P solution, followed by a Lympholyte density gradient separation; finally, functional assays and a staining with dithizone were carried out. Isolated pancreatic islets exhibited functional responses to glucose and arginine stimulation mirroring donors' metabolic profiles, with insulin secretion significantly decreasing in diabetic islets compared to non-diabetic islets; conversely, proinsulin secretion showed an increasing trend from non-diabetic to diabetic islets. This novel islet isolation method from living patients undergoing partial pancreatectomy offers a valuable opportunity for targeted study of islet physiology, with the primary advantage of being time-effective and successfully preserving islet viability and functionality. It enables the generation of islet preparations closely reflecting donors’ clinical profiles, simplifying the isola-tion process and eliminating the need for a Ricordi chamber. Thus, this method holds promises for advancing our understanding of diabetes and for new personalized pharmacological approaches
The Clinical Frailty Scale (CFS) as an Independent Prognostic Factor for Patients ≥80 Years with Small Bowel Obstruction (SBO)
Background: SBO is a potentially life-threatening condition that often affects older patients. Frailty, more than age, is expected to play a crucial role in predicting SBO prognosis in this population. This study aims to define the influence of Clinical Frailty Scale (CFS) on mortality and major complications in patients ≥80 years with diagnosis of SBO at the emergency department (ED). Methods: All patients aged ≥80 years admitted to our ED for SBO from January 2015 to September 2020 were enrolled. Frailty was assessed through the CFS, and then analyzed both as a continuous and a dichotomous variable. The endpoints were in-hospital mortality and major complications. Results: A total of 424 patients were enrolled. Higher mortality (20.8% vs 8.6%, p<0.001), longer hospital stay (9 [range 5-14] days vs 7 [range 4-12] days, p=0.014), and higher rate of major complications (29.9% vs 17.9%, p=0.004) were associated with CFS ≥7. CFS score and bloodstream infection were the only independent prognostic factors for mortality (OR 1.72 [CI: 1.29-2.29], p<0.001; OR 4.69 [CI: 1.74-12.6], p=0.002, respectively). Furthermore, CFS score, male sex and surgery were predictive factors for major complications (OR 1.41 [CI: 1.13-1.75], p=0.002; OR 1.67 [CI: 1.03-2.71], p=0.038); OR 1.91 [CI: 1.17-3.12], p=0.01; respectively). At multivariate analysis, for every 1-point increase in CFS score, the odds of mortality and the odds of major complications increased 1.72-fold and 1.41-fold, respectively. Conclusion: The increase in CFS is directly associated with an increased risk of mortality and major complications. The presence of severe frailty could effectively predict an increased risk of in-hospital death regardless of the treatment administered. The employment of CFS in elderly patients could help the identification of the need for closer monitoring and proper goals of care
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