Computer-aided engineering of stabilized fibroblast growth factor 21

FGF21 is an endocrine signaling protein belonging to the family of fibroblast growth factors (FGFs). It has emerged as a molecule of interest for treating various metabolic diseases due to its role in regulating glucogenesis and ketogenesis in the liver. However, FGF21 is prone to heat, proteolytic, and acid-mediated degradation, and its low molecular weight makes it susceptible to kidney clearance, significantly reducing its therapeutic potential. Protein engineering studies addressing these challenges have generally shown that increasing the thermostability of FGF21 led to improved pharmacokinetics. Here, we describe the computer-aided design and experimental characterization of FGF21 variants with enhanced melting temperature up to 15 °C, uncompromised efficacy at activation of MAPK/ERK signaling in Hep G2 cell culture, and ability to stimulate proliferation of Hep G2 and NIH 3T3 fibroblasts cells comparable with FGF21-WT. We propose that stabilizing the FGF21 molecule by rational design should be combined with other reported stabilization strategies to maximize the pharmaceutical potential of FGF21.

EURO-MUSCULUS/USPRM Dynamic Ultrasound Protocols for Ankle/Foot

ABSTRACT

In this dynamic scanning protocol, ultrasound examination of the ankle is described using various maneuvers to assess different conditions. Real-time patient examination and scanning videos are used for better simulation of daily clinical practice. The protocol is prepared by several/international experts in the field of musculoskeletal ultrasound and within the umbrella of European Musculoskeletal Ultrasound Study Group in Physical and Rehabilitation Medicine/Ultrasound Study Group of the International Society of Physical and Rehabilitation Medicine.

Cerebral organoids derived from patients with Alzheimer's disease with PSEN1/2 mutations have defective tissue patterning and altered development

During the past two decades, induced pluripotent stem cells (iPSCs) have been widely used to study human neural development and disease. Especially in the field of Alzheimer's disease (AD), remarkable effort has been put into investigating molecular mechanisms behind this disease. Then, with the advent of 3D neuronal cultures and cerebral organoids (COs), several studies have demonstrated that this model can adequately mimic familial and sporadic AD. Therefore, we created an AD-CO model using iPSCs derived from patients with familial AD forms and explored early events and the progression of AD pathogenesis. Our study demonstrated that COs derived from three AD-iPSC lines with PSEN1(A246E) or PSEN2(N141I) mutations developed the AD-specific markers in vitro, yet they also uncover tissue patterning defects and altered development. These findings are complemented by single-cell sequencing data confirming this observation and uncovering that neurons in AD-COs likely differentiate prematurely.

Administration of mucolytic solution before upper endoscopy - double-blind, monocentric, randomized study

AIMS

Sufficient visibility of the mucosa during upper endoscopy is crucial for successful diagnosis, especially for early neoplastic lesions. Data documenting the effect of administration of mucolytic solution prior to gastroscopy in order to improve mucosal visibility are limited in Europe. The aim of the study was to assess the score of mucosal visibility in the upper gastrointestinal tract after administration of the mucolytic solution defined by us.

PATIENTS AND METHODS

This is a monocentric, double-blind, randomized study involving 134 patients indicated for diagnostic upper endoscopy. Patients were randomly assigned to one of three arms, with mucolytic solution (100 mL water + 400 mg N-acetylcysteine + 20 mg simethicone), without the solution , and with 100 mL pure water. During the examination, 11 photographs were taken in defined areas. The visibility score was given by the sum of the score 0-5 from 5 defined localities evaluated by a blinded endoscopist and subsequently by two blinded endoscopists. Other parameters monitored were examination time and a semiquantitative evaluation of residual gastric fluid.

RESULTS

The basic characteristics of the group (sex, age, indications for examination) were comparable between arms. The visibility score was similar in all arms - 17.4 ± 1.9 vs. 17.0 ± 2.0 vs. 17.6 ± 1.8 (P=0.32). The examination time and the amount of residual fluid in the stomach were comparable in all arms.

CONCLUSIONS

Administration of the mucolytic solution in our study did not increase the mucosal visibility score in the esophagus, stomach and duodenum.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02967094.

Endosonography-Guided Fine-Needle Aspiration versus "Key-Hole Biopsy" in the diagnostics of upper gastrointestinal subepithelial tumors. A prospective randomized interventional study

BACKGROUND

The management and prognosis of subepithelial tumors (SETs) of the upper gastrointestinal tract depend on the correct preoperative evaluation, including tissue diagnosis in selected cases. Several methods providing deep tissue sampling for cytological and/or histological examinations have been described but their diagnostic yield and precise position in the diagnostic algorithm remain to be established. This prospective randomized study aims to compare the Endosonography-Guided Fine-Needle Aspiration (EUS-FNA) to Key-Hole Biopsy (KHB) in cytological or histological diagnostics of upper gastrointestinal SETs.

PATIENTS AND METHODS

This study was conducted in a single tertiary endoscopy center in Ostrava, Czech Republic between November 2010 and October 2015. Patients with endoscopically detected SETs of the upper gastrointestinal tract with a diameter ≥ 2 cm, were randomized to either the EUS-FNA with 22G needle, or to the Key Hole biopsy (forceps biopsy through mucosal incision) groups. The main study outcomes were success rate of tissue diagnostics and, in the cases of Gastrointestinal Stromal Tumours (GIST), possibility of determining mitotic activity. A cross-over examination was performed in situations where the first method had failed.

RESULTS

A total of 46 consecutive patients were randomized. Of these, 24 (52%) and 22 (48%) were randomized to EUS-FNA group and KHB arm, respectively. 5 SETs (11%) were detected in the esophagus, 40 (87%) in the stomach and 1 (2%) in the duodenum. The definitive diagnosis was established by the first sampling method in 42 (91%) patients, including 22 (92%) in the EUS-FNA group and 20 (91%) in the KHB group (P=0.999), and after a cross-over in another 3 (7%) patients. The most prevalent SET was GIST (70%). Although some mitotic activity could be observed in 11 patients, the mitotic index could be diagnosed in none of them. Of a total of 20 surgically treated patients, preoperative and postoperative tissue diagnosis corresponded in 19/20 (95%) cases, including 100% in FNA group and 91% in KHB group (P=0.999). No adverse events of tissue sampling occurred in the study.

CONCLUSIONS

Deep tissue sampling by EUS-FNA and KHB are equally effective in the diagnostics of SETs of the upper gastrointestinal tract ≥ 2 cm. However, neither EUS-FNA nor KHB provided adequate tissue sample to determine mitotic index.

TRIAL REGISTRATION

Clinicaltrials.gov (NCT02025244).

Dystrophin Deficiency Leads to Genomic Instability in Human Pluripotent Stem Cells via NO Synthase-Induced Oxidative Stress

Recent data on Duchenne muscular dystrophy (DMD) show myocyte progenitor's involvement in the disease pathology often leading to the DMD patient's death. The molecular mechanism underlying stem cell impairment in DMD has not been described. We created dystrophin-deficient human pluripotent stem cell (hPSC) lines by reprogramming cells from two DMD patients, and also by introducing dystrophin mutation into human embryonic stem cells via CRISPR/Cas9. While dystrophin is expressed in healthy hPSC, its deficiency in DMD hPSC lines induces the release of reactive oxygen species (ROS) through dysregulated activity of all three isoforms of nitric oxide synthase (further abrev. as, NOS). NOS-induced ROS release leads to DNA damage and genomic instability in DMD hPSC. We were able to reduce both the ROS release as well as DNA damage to the level of wild-type hPSC by inhibiting NOS activity.

Water exchange for screening colonoscopy increases adenoma detection rate: a multicenter, double-blinded, randomized controlled trial

Background and study aims Single-center studies, which were retrospective and/or involved unblinded colonoscopists, have suggested that water exchange, but not water immersion, compared with air insufflation significantly increases the adenoma detection rate (ADR), particularly in the proximal and right colon. Head-to-head comparison of the three techniques with ADR as primary outcome and blinded colonoscopists has not been reported to date. In a randomized controlled trial with blinded colonoscopists, we aimed to evaluate the impact of the three insertion techniques on ADR. Patients and methods A total of 1224 patients aged 50 - 70 years (672 males) and undergoing screening colonoscopy were randomized 1:1:1 to water exchange, water immersion, or air insufflation. Split-dose bowel preparation was adopted to optimize colon cleansing. After the cecum had been reached, a second colonoscopist who was blinded to the insertion technique performed the withdrawal. The primary outcome was overall ADR according to the three insertion techniques (water exchange, water immersion, and air insufflation). Secondary outcomes were other pertinent overall and right colon procedure-related measures. Results Baseline characteristics of the three groups were comparable. Compared with air insufflation, water exchange achieved a significantly higher overall ADR (49.3 %, 95 % confidence interval [CI] 44.3 % - 54.2 % vs. 40.4 % 95 %CI 35.6 % - 45.3 %; P  = 0.03); water exchange showed comparable overall ADR vs. water immersion (43.4 %, 95 %CI 38.5 % - 48.3 %; P  = 0.28). In the right colon, water exchange achieved a higher ADR than air insufflation (24.0 %, 95 %CI 20.0 % - 28.5 % vs. 16.9 %, 95 %CI 13.4 % - 20.9 %; P  = 0.04) and a higher advanced ADR (6.1 %, 95 %CI 4.0 % - 9.0 % vs. 2.5 %, 95 %CI 1.2 % - 4.6 %; P = 0.03). Compared with air insufflation, the mean number of adenomas per procedure was significantly higher with water exchange (P = 0.04). Water exchange achieved the highest cleanliness scores (overall and in the right colon). These variables were comparable between water immersion and air insufflation. Conclusions The design with blinded observers strengthens the validity of the observation that water exchange, but not water immersion, can achieve significantly higher adenoma detection than air insufflation. Based on this evidence, the use of water exchange should be encouraged.Trial registered at ClinicalTrials.gov (NCT02041507).

LESSONS LEARNED FROM THE EURADOS SURVEY ON INDIVIDUAL MONITORING DATA AND INTERNAL DOSE ASSESSMENTS OF FOREIGNERS EXPOSED IN JAPAN FOLLOWING THE FUKUSHIMA DAIICHI NPP ACCIDENT

European Radiation Dosimetry Group e.V. (EURADOS) survey on individual monitoring data and dose assessment has been carried out for 550 foreigners returning home after being exposed in Japan to intakes of radionuclides (mainly (131)I, (132)I, (132)Te, (134)Cs and (137)Cs) as a consequence of the Fukushima Daiichi NPP accident. In vivo and in vitro measurements were performed in their respective countries at an early stage after that accident. Intakes of radionuclides were detected in 208 persons from Europe and Canada, but the committed effective dose E(50) was below the annual dose limit for the public (<1 mSv) in all the cases. Lessons learned from this EURADOS survey are presented here regarding not only internal dosimetry issues, but also the management of the emergency situation, the perception of the risk of health effects due to radiation and the communication with exposed persons who showed anxiety and lack of trust in monitoring data and dose assessments.

High-frequency ultrasound probe sonography staging for colorectal neoplasia with superficial morphology: its utility and impact on patient management

BACKGROUND

This prospective study aimed to evaluate the impact of high-frequency ultrasound probe sonography (HFUPS) staging on the management of patients with superficial colorectal neoplasia (SCN) as determined by the endoscopic characteristics of lesions.

METHODS

Consecutive patients referred for endoscopic treatment of nonpedunculated SCN were enrolled in this study. A lesion was considered high risk if a depressed area or invasive pit pattern was present. The gold standard for final staging included histology from endoscopic or surgical resection. The impact on treatment was defined as any modification of the therapeutic algorithm based on the result of the HFUPS examination compared with that based on endoscopy alone.

RESULTS

In this study, 48 lesions in 48 patients were evaluated. Of these, 28 (58%) were considered high risk, and the remaining 20 (42%) were regarded as low risk. A total of seven lesions (15%) that could not be examined with HFUPS and another non-neoplastic lesion were excluded from final analysis. For the remaining 40 lesions, the overall accuracy of the HFUPS examination to predict the correct T-stage was 90% (95% confidence interval [CI], 77-96%). The HFUPS examination had a positive impact on the treatment of 0 low-risk and 11 high-risk (42%) lesions.

CONCLUSION

The impact of HFUPS on the treatment of SCN depends on their endoscopic characteristics. It is negligible for low-risk SCNs, and these lesions can be treated on the basis of their endoscopic appearance alone. Nevertheless, compared with endoscopy alone, HFUPS changed the subsequent therapeutic approach in a positive way for up to 42% of high-risk lesions, including those with a depressed component and an invasive pit pattern. These endoscopic features can therefore be recommended as the entry criteria for an HFUPS examination.

Endoscopic ultrasound-guided fine needle aspiration of pancreatic masses: the utility and impact on management of patients

OBJECTIVE

It is controversial whether endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is beneficial in all patients with suspected pancreatic cancer. The aim of this study was to assess diagnostic yield, safety and impact of EUS-FNA on management of patients with solid pancreatic mass.

MATERIAL AND METHODS

Consecutive patients undergoing EUS-FNA of solid pancreatic mass were enrolled. Gold standard for final diagnosis included histology from surgical resection. In patients without surgery, clinical evaluation methods and repeated imaging studies were used for the comparison of initial cytology and final diagnosis. Patients were followed-up prospectively focusing on subsequent treatment.

RESULTS

Among 207 enrolled patients, final diagnosis was malignant in 163 (78.6%) and benign in 44 (21.4%). The sensitivity, specificity and accuracy of EUS-FNA in diagnosing pancreatic cancer were 92.6% (95% CI: 87.20-95.96), 88.6% (95% CI: 74.64-95.64) and 91.8% (95% CI: 87.24-94.81), respectively. No major and five (2.4%) minor complications occurred. Of 151 true-positive patients by EUS-FNA, 57 (37.7%) were surgically explored, of whom 28 (49.1%) underwent resection. Ten of 12 patients with false-negative cytology were explored based on detection of mass on EUS, of whom two had a delay due to false-negative cytology without curative treatment. From the whole study cohort, EUS-FNA had positive and negative impacts on subsequent management in 136 (65.7%) and 2 (0.9%) patients, respectively.

CONCLUSIONS

EUS-FNA provides accurate diagnosis in 92% and has positive therapeutic impact in two-thirds of patients with solid pancreatic mass. Despite negative cytology, surgical exploration is recommended in clinical suspicion for pancreatic cancer and solid mass on EUS.

Impact of a metabolic stone clinic on management of patients with cystinuria: 5 years follow-up

PURPOSE

Cystinuric patients develop new stones and exhibit stone growth despite conservative measures and often require surgical intervention. There have been reports of better outcome both in surgical intervention rates and compliance when patients were referred to dedicated metabolic stone clinics. We wish to report our experience in the running of a metabolic stone disease clinic and to compare our intervention rates to the pre-metabolic stone clinic period in our department.

PATIENTS AND METHODS

We reviewed retrospectively our cystinuria patients' database between the years of 1992 and 2008. Patients were divided into two groups. Group A patients (n=28) were treated before the introduction of a dedicated stone clinic (years 1992-2002) and group B patients (n=28) after the establishment of the metabolic stone clinic but every group B patient had a minimum follow up of 5 years. 21 patients were common between the two groups. Main therapy included hyperdiuresis and alkalization. Parameters recorded included the number of clinic visits, whether the patients were stone free or asymptomatic at the time of our review and the nature and frequency of surgical intervention.

RESULTS

A total number of 145 procedures were carried out in group A including 89 ESWL, 27 PCNL, 24 ureteroscopy retrograde lithotripsies and 5 open procedures. In group B, a total of 54 procedures were carried out and included 6 ESWL, 5 PCNL and 43 ureteroscopy laser lithotripsies. The average number of surgical interventions per patient per year was 0.74 and 0.34 in group A and B respectively. The number of clinic attendances increased in group B to 279 from 188 in group A. Stone free rates were 46% for group A and 50% for group B patients but all group B patients were asymptomatic at the time of our review.

CONCLUSIONS

The introduction of a dedicated cystinuria clinic halved the intervention rate in this complicated group of patients. The majority of surgical procedures shifted towards ureteroscopies (both as inpatients and as day case procedures). We believe that cystine stone patients should be managed in a devoted metabolic stone clinic. With this approach, compliance is better achieved and surgical intervention is less, resulting in better clinical outcome, and less burden both for the patient and the urological services.

Laterally spreading tumors--experience based on 138 consecutive cases

BACKGROUND/AIMS

Laterally spreading tumors (LST) are flat elevated neoplastic lesions with diameters equal to or greater than 10 mm. The treatment results of 138 lesions in 131 patients are presented here as a part of a retrospective analysis.

METHODOLOGY

Two gastroenterology centers participated in the study in the period from 1/2002-12/2006. During colonoscopy, each superficial lesion was classified according to the Paris endoscopic classification. Endoscopic mucosal resection (EMR) lift and cut was employed. Treatment was considered successful when both endoscopic and histo-pathological criteria of complete resection were fulfilled.

RESULTS

A total of 138 LST in 131 patients were diagnosed. Average LST diameter was 25 mm. A total of 5 (3.6%) lesions in 4 patients were referred for primary surgery. One patient was treated with argon plasma coagulation only. EMR was attempted for 132/138 (95.7%) of all LST and was successful in 125 (90.6%) cases. Complications occured in 16/132 (12.1%) patients. Severe complications, defined as decession, emergency surgery, emergency endoscopy and transfusion of eryhrocyte concentrate occured in 5/132 (3.8%). One (0.7%) 69 year-old-male patient died on the third day following EMR due to complications of acute myocardial infarction.

CONCLUSION

LST lesions could be efficiently treated with EMR lift and cut method with a reasonable rate of complications.