MicroRNAs in metabolism

MicroRNAs (miRNAs) have within the past decade emerged as key regulators of metabolic homoeostasis. Major tissues in intermediary metabolism important during development of the metabolic syndrome, such as β-cells, liver, skeletal and heart muscle as well as adipose tissue, have all been shown to be affected by miRNAs. In the pancreatic β-cell, a number of miRNAs are important in maintaining the balance between differentiation and proliferation (miR-200 and miR-29 families) and insulin exocytosis in the differentiated state is controlled by miR-7, miR-375 and miR-335. MiR-33a and MiR-33b play crucial roles in cholesterol and lipid metabolism, whereas miR-103 and miR-107 regulates hepatic insulin sensitivity. In muscle tissue, a defined number of miRNAs (miR-1, miR-133, miR-206) control myofibre type switch and induce myogenic differentiation programmes. Similarly, in adipose tissue, a defined number of miRNAs control white to brown adipocyte conversion or differentiation (miR-365, miR-133, miR-455). The discovery of circulating miRNAs in exosomes emphasizes their importance as both endocrine signalling molecules and potentially disease markers. Their dysregulation in metabolic diseases, such as obesity, type 2 diabetes and atherosclerosis stresses their potential as therapeutic targets. This review emphasizes current ideas and controversies within miRNA research in metabolism.

Overview of diagnostic performance and results for the first operation phase in Wendelstein 7-X (invited)

Wendelstein 7-X, a superconducting optimized stellarator built in Greifswald/Germany, started its first plasmas with the last closed flux surface (LCFS) defined by 5 uncooled graphite limiters in December 2015. At the end of the 10 weeks long experimental campaign (OP1.1) more than 20 independent diagnostic systems were in operation, allowing detailed studies of many interesting plasma phenomena. For example, fast neutral gas manometers supported by video cameras (including one fast-frame camera with frame rates of tens of kHz) as well as visible cameras with different interference filters, with field of views covering all ten half-modules of the stellarator, discovered a MARFE-like radiation zone on the inboard side of machine module 4. This structure is presumably triggered by an inadvertent plasma-wall interaction in module 4 resulting in a high impurity influx that terminates some discharges by radiation cooling. The main plasma parameters achieved in OP1.1 exceeded predicted values in discharges of a length reaching 6 s. Although OP1.1 is characterized by short pulses, many of the diagnostics are already designed for quasi-steady state operation of 30 min discharges heated at 10 MW of ECRH. An overview of diagnostic performance for OP1.1 is given, including some highlights from the physics campaigns.

[Diagnosis and treatment of billiary ileus]

INTRODUCTION

Biliary ileus represents only 14% of mechanical obstructions of the gastrointestinal tract. However, the rate of non-strangulated small bowel obstructions reaches as much as 25% in patients over 65 years of age. Usually, a pressure necrosis is created by a large gallstone that passes through the developed biliodigestive fistula, subsequently obturating the gastrointestinal tract.

CASE REPORTS

35 patients underwent a surgical procedure at the Department of Surgery, Teaching Hospital Pilsen for biliary ileus from January 1, 2000 to January 31, 2015. Mean age was 79 years (median 78 years; min. 58 years; max. 92 years). Aerobilia was visible in abdominal X-ray scans in 7 cases (26%) of 27 acquired images. Preoperatively, colonoscopy was done 2 times and esophagogastroduodenoscopy 9 times. Regarding surgical procedures, enterolithotomy was done in 21 cases, extraction of the gallstone from gastrotomy was done 3 times, small bowel resection 7 times, Hartmann resection 1 time, resection of ileoascendentoanastomosis 1 time, and extraction of the gallstone from duodenotomy with duodenojejunoanastomosis and cholecystectomy was done in 1 case. Ileotransversoanastomosis was performed in 1 case. Postoperative 30-day mortality was 14.3%. Postoperative morbidity according Clavien-Dindo was 22.8% for grade 1, 5.7% for grade 2, 11.5% for grade 3, and 11.5% for grade 4. A recurrence was observed in 8.8%. Primary treatment of the fistula and cholecystectomy were done in 1 case.

CONCLUSION

The indication of primary biliodigestive fistula treatment always depends on the general condition of the patient and on the local finding in the gallbladder area. Residual fistula increases the risk of reccurence, but primary treatment is associated with higher mortality. It is also important to duly revise the entire bowel to avoid an early reccurence due to multiple gallstones.

KEY WORDS

biliary ileus diagnosis treatment.

[Coincidence of colonic lymphoma and gallstone ileus - case report]

INTRODUCTION

Primary colonic lymphoma is a very rare malignant disease of the gastrointestinal tract, accounting for 14% of all malignant diseases in this location. It is classified in the group of extranodal lymphomas; its long-term asymptomatic progression makes it different from common colorectal carcinomas making its diagnosis very difficult, more often accidental. Gallstone ileus is quite an uncommon complication of cholecystolithiasis diagnosed with difficulty. Up to 50% of cases are diagnosed during surgery. The obturated location depends on the size of the stone, location of the conjunction between the biliary and gastrointestinal tracts, and also on any preexisting stenosis due to another unknown pathology.

CASE REPORT

We present a case of an 86-year-old man treated for acute diverticulitis with typical clinical symptoms. Following further examination (colonoscopy, computed tomography) revealed a tumour-like infiltration in the sigmoid colon wall and a voluminous polyp was suspected according to the colonoscopy. Computed tomography described an obstruction by a biliary stone tumbling through the cholecystocolonic fistula. Subsequent biopsy supported the suspected malignant etiology. The patient underwent resection of the sigmoid colon sec. Hartmann; an infiltration was found in the subhepatic space, which corresponded to the described fistulisation between the biliary tract and the colon. A large 40 mm gallstone was found in the resected sigmoid colon over the stenosis and the bowel wall showed diffuse thickening with several polyps; final histopathological assessment confirmed malignant lymphoma of the plasmocytoma type. No serious complications occurred in the postoperative period; after healing, the patient was transferred to hematooncology care.

CONCLUSION

The article describes the presence of two rare diseases - colonic lymphoma and gallstone ileus. Clearly, without the biliary stone obstruction in the preexisting tumorous stenosis in the sigmoid colon, the malignant hematooncology disease would not have been diagnosed.

KEY WORDS

primary colonic lymphoma - gallstone ileus - complication of the cholecystolithiasis - extranodal lymphoma - acute diverticulitis.

[Mediastinitis after esophageal perforation]

INTRODUCTION

Assessment of therapy in patients with mediastinal infection resulting from esophageal perforation.

MATERIAL AND METHODS

Retrospective (2008-2012) processing of a group of surgically treated patients. The aspects assessed were aetiology, the surgical methods applied and the length of therapy.

RESULTS

The total number of patients treated was 16. In 8 cases, the aetiology was iatrogenic (3 cases of leaking esophageal anastomosis in consequence of resection of the esophagus, 2 cases of perforation after fundoplication, 1 case of esophageal cardiomyotomy, and 2 cases of perforation during endoscopy). In 4 patients, the aetiology was spontaneous perforation, impacted foreign bodies caused difficulties to 3 patients, and the last cause was acid corrosive esophagitis. A stent was applied in all the patients at the site of the defect. The mediastinitis was drained through the access from thoracotomy or left thoracolaparotomy, respectively (8 cases), or by combination of laparotomy/laparostomy and pleural drainage (5 cases). Pleural (in 3 cases) and neck (1 case) drainage meant minimum intervention. Esophagectomy was not carried out in any of the patients. 4 patients died. The average period of time for which the stent was left in situ was 53.7 days; the average time of hospitalization in surviving patients was 53.4 days.

CONCLUSION

Stent application does not show any difference regarding patients' survival (25% mortality), but enables shortening the total therapy time and, predominantly, preserving the native esophagus.