PARP14 and PARP9/DTX3L regulate interferon-induced ADP-ribosylation.

PARP-catalysed ADP-ribosylation (ADPr) is important in regulating various cellular pathways. Until recently, PARP-dependent mono-ADP-ribosylation has been poorly understood due to the lack of sensitive detection methods. Here, we utilised an improved antibody to detect mono-ADP-ribosylation. We visualised endogenous interferon (IFN)-induced ADP-ribosylation and show that PARP14 is a major enzyme responsible for this modification. Fittingly, this signalling is reversed by the macrodomain from SARS-CoV-2 (Mac1), providing a possible mechanism by which Mac1 counteracts the activity of antiviral PARPs. Our data also elucidate a major role of PARP9 and its binding partner, the E3 ubiquitin ligase DTX3L, in regulating PARP14 activity through protein-protein interactions and by the hydrolytic activity of PARP9 macrodomain 1. Finally, we also present the first visualisation of ADPr-dependent ubiquitylation in the IFN response. These approaches should further advance our understanding of IFN-induced ADPr and ubiquitin signalling processes and could shed light on how different pathogens avoid such defence pathways.

HUWE1 employs a giant substrate-binding ring to feed and regulate its HECT E3 domain.

HUWE1 is a universal quality-control E3 ligase that marks diverse client proteins for proteasomal degradation. Although the giant HECT enzyme is an essential component of the ubiquitin-proteasome system closely linked with severe human diseases, its molecular mechanism is little understood. Here, we present the crystal structure of Nematocida HUWE1, revealing how a single E3 enzyme has specificity for a multitude of unrelated substrates. The protein adopts a remarkable snake-like structure, where the C-terminal HECT domain heads an extended alpha-solenoid body that coils in on itself and houses various protein-protein interaction modules. Our integrative structural analysis shows that this ring structure is highly dynamic, enabling the flexible HECT domain to reach protein targets presented by the various acceptor sites. Together, our data demonstrate how HUWE1 is regulated by its unique structure, adapting a promiscuous E3 ligase to selectively target unassembled orphan proteins.

Moyamoya disease factor RNF213 is a giant E3 ligase with a dynein-like core and a distinct ubiquitin-transfer mechanism.

RNF213 is the major susceptibility factor for Moyamoya disease, a progressive cerebrovascular disorder that often leads to brain stroke in adults and children. Characterization of disease-associated mutations has been complicated by the enormous size of RNF213. Here, we present the cryo-EM structure of mouse RNF213. The structure reveals the intricate fold of the 584 kDa protein, comprising an N-terminal stalk, a dynein-like core with six ATPase units, and a multidomain E3 module. Collaboration with UbcH7, a cysteine-reactive E2, points to an unexplored ubiquitin-transfer mechanism that proceeds in a RING-independent manner. Moreover, we show that pathologic MMD mutations cluster in the composite E3 domain, likely interfering with substrate ubiquitination. In conclusion, the structure of RNF213 uncovers a distinct type of an E3 enzyme, highlighting the growing mechanistic diversity in ubiquitination cascades. Our results also provide the molecular framework for investigating the emerging role of RNF213 in lipid metabolism, hypoxia, and angiogenesis.

Moyamoya disease is a genetic disorder affecting both adults and children. It is characterized by narrowing of the blood vessels in the brain, which can lead to strokes. Moyamoya patients often have mutations in the gene for a protein called RNF213. This protein is linked to multiple processes in the body, including the development of blood vessels. Despite this, its role in Moyamoya disease is still something of a mystery. RNF213 is known to fall into two protein 'classes'. First, it is an E3 enzyme. This type of protein tags unwanted or defective proteins for disposal by the cell. Second, it is a motor protein. Motor proteins contain tiny molecular 'engines', called ATPases, that normally convert chemical energy to movement. No other human protein combines these two activities, making RNF213 unique. RNF213 is also an extremely large protein, which means it is difficult to manipulate in the laboratory and thus hard to study. Scientists still need more detailed information on RNF213's structure and chemical activity before we can understand what the mutant protein might be doing in Moyamoya disease. Ahel et al. therefore set out to make the RNF213 protein and 'dissect' it in a test tube. Electron microscopy experiments using the mouse-version of RNF213 revealed that it consisted of a single, giant molecule, folded up to form three regions with distinct structures. These were a long 'arm' at one end, a ring-shaped part in the middle, containing the ATPase 'motor', and the E3 enzyme module at the other end. Further chemical analysis showed that RNF213's ATPase and E3 modules worked in unexpected ways. Although the ATPase did resemble another well-known motor protein, in RNF213 it did not generate movement but rather appeared to act like an intricate molecular 'switch'. The E3 module of RNF213 'tagged' other molecules as expected but did not contain an additional structure that all other known E3 enzymes need to work properly. This suggests that RNF213 represents a distinct class of E3 enzymes. Biochemical tests of the mutation most commonly found in Moyamoya patients revealed that it left RNF213's overall structure, ATPase motor and E3 module intact. That is, the disease-causing mutation appeared to hinder interactions with other partner proteins, rather than disrupting RNF213 itself. By providing the first detailed molecular description of the architecture of RNF213, Ahel et al. hope that these findings will help future investigations of both this giant protein's biological role in the cell and its contribution to Moyamoya disease.

Treatment of Kidney Stone in a Kidney-Transplanted Patient with Mini-Percutaneous Laser Lithotripsy: A Case Report.

We report a case of a kidney-transplanted patient with urolithiasis treated with mini-percutaneous laser lithotripsy. The patient presented with renal dysfunction and graft hydronephrosis. Diagnostic procedures revealed ureterolithiasis as a cause of obstruction, and percutaneous nephrostomy was inserted as a temporary solution. Before surgery, the stone migrated to the renal pelvis. Mini-percutaneous laser lithotripsy was successfully performed, and during surgery, all stone fragments were removed. Six months after successful treatment, the patient has good functioning and stone-free graft.

[MINI-PERCUTANEOUS NEPHROLITHOTRIPSY ­ OUR FIRST EXPERIENCE]. / MINIPERKUTANA NEFROLITOTRIPSIJA ­ NASA PRVA ISKUSTVA.

Urolithiasis is a significant problem in the developed countries due to the increased number of patients with stones. Just a few decades ago open surgery was the only surgical treatment which is today, in most cases, replaced with minimally-invasive methods. One of these new methods is mini-percutaneous nephrolihotripsy. We present four patients in whom mini-percutaneous nephrolithotripsy was performed. In all patients the stone was located in the renal pelvis. In three patients the stone was in the native kidney and in one in the transplanted kidney. In all patients laser lithotripsy was successfully performed. On the control x-ray the residual fragments were not found in any patients. Mini-percutaneous nephrolithotripsy is a minimally-invasive method which is successfull in the treatment of nephfrolithiasis in native and transplanted kidneys.

10-year survival of a patient with metastatic prostate cancer: Case report and literature review.

Prostate cancer is the most common malignancy in men. The 5-year relative survival for all stages combined is 98.8%. Patients diagnosed with metastatic prostate cancer have median survival from 2 to 3 years. We describe a case of 64-year old man who clinically presented with inguinal lymphadenopathy. Because of elevated PSA levels biopsy of prostate was done and adenocarcinoma was diagnosed. Biopsy of inguinal lymph nodes confirmed the diagnosis of prostate cancer. Hormonal treatment was started and at the most recent follow-up, 10 years later, the patient is asymptomatic with no clinical signs of disseminated disease.

Transurethral incision of the bladder neck in a woman with primary bladder neck obstruction after kidney transplantation.

Voiding dysfunction is frequently seen in the early posttransplant period. Among other causes, this condition can arise due to bladder outlet obstruction. Primary bladder neck obstruction (PBNO) is a possible but very rare cause of bladder outlet obstruction. We present the case of a 52-year-old woman who, after kidney transplantation, presented with PBNO. The diagnosis was established based on symptoms, uroflowmetry, and multichannel urodynamics with electromyography. The transurethral incision of the bladder neck was made at the 5- and 7-o'clock position. After the operation, the maximal flow rate was significantly increased, and postvoid residual urine was decreased compared to the preoperative findings. The patient was followed for 5 years, and her voiding improvement is persistent. This is the first reported case of PBNO treated with a transurethral incision of the bladder neck in a posttransplantation female patient.

Different presentations of renal cell cancer on ultrasound and computerized tomography.

Renal cell carcinoma (RCC) is the most common malignant tumor of the kidney. The major goal of imaging techniques is to correctly differentiate between benign and malignant renal lesions. We present the cases of six patients with renal masses that were interpreted completely differently based on ultrasound (US) and computerized tomography (CT) findings.From January 1st, 2008 to March 1st, 2014, 307 patients from our center underwent nephrectomy for RCC. In all patients US and CT were performed before the operation.In six patients, the US indicated a focal, solid renal lesion that was interpreted by CT as a cystic lesion (Bosniak II-III). Because discrepancies were evident, renal biopsies were performed. The biopsies revealed RCC in the six patients, all of whom underwent subsequent nephrectomy. All of the patients were confirmed to have macroscopically solid RCC without any cystic components.In most cases, CT is the most accurate diagnostic technique for the clinical diagnostic classification of renal masses. In cases where US characterizes a renal lesion as solid, despite CT findings of a cystic lesion, kidney biopsies are recommended. The 6 cases reported here support our belief that, in diagnostic processes of RCC, these techniques should be complementary used.

[Lymphocele and renal transplantation]. / Limfocele i transplantacija bubrega.

Lymphoceles are a well-known surgical complication of kidney transplantation. We retrospectively analyzed patients with lymphoceles among our renal transplant recipients. During the last 39 years, we performed 922 renal transplantations. Lymphoceles were diagnosed and treated in 45 (4.9%) patients. We used the following methods: percutaneous drainage with instillation of povidone-iodide in 36 (80%), percutaneous drainage with instillation of tetracycline in one (2.2%), percutaneous aspiration in four (8.9%) and surgical treatment in four (8.9%) patients. In all four (8.9%) patients with relapse, secondary procedure was successful. In total, open surgery was done in five (11.1%) and laparoscopy in four (8.9%) patients. Percutaneous drainage of lymphoceles, with or without the instillation of a sclerosant, is the first-line treatment. Laparoscopic fenestration of lymphoceles has become an alternative to percutaneous drainage, especially in case of post-drainage relapse.

Transrectal sonography in prostate cancer detection--our 25 years experience of implementation.

Prostate cancer is a leading public health problem of male population in developed countries. Gold standard for prostate cancer diagnosis is true cut biopsy guided by transrectal ultrasound. Aim of this study was to determine sensitivity, specificity, accuracy, positive and negative predictive value of transrectal sonography (TRUS) in prostate cancer detection. The analysis was made for two time periods, before and after routine implementation of prostate specific antigen (PSA) in prostate cancer diagnostics. From 1984 to 1993 TRUS guided prostate biopsy was performed in 564, and from 1994 to 2008 in 5678 patients. In the second period PSA was routinely used in prostate cancer diagnostics. In the first period by TRUS we have made an exact diagnosis of prostate cancer in 18.97% of patients what was confirmed by biopsy. 4.61% ware false positive and 11.34% ware false negative. In the second period prostate cancer was recognized in 30.34% of patients, confirmed by biopsy. False positive cases ware 6.11% and false negative 29.31%. Sensitivity of transrectal sonography in the first period was 62.57%, specificity 94.2%, accuracy 86.2%, positive predictive value 80.45% and negative predictive value 87.72%. In the second period sensitivity was 50.87%, specificity 91.93%, accuracy 73.84%, positive predictive value 83.24% and negative predictive value 70.39%. Based on our experience we can conclude that prostate cancer is mostly found in the peripheral zone. Smaller tumors are hypoechoic and bigger tumors are hyperechoic. Prostate cancer lesions are impossible to differentiate from chronic prostatitis only by TRUS. Implementation of PSA has significantly decrease sensitivity, accuracy and negative predictive value of TRUS in prostate cancer detection. TRUS guided true cut biopsy is a gold standard in prostate cancer diagnostics.

Application of wound closure Molndal technique after laparoscopic cholecystectomy--initial comparative study.

Because of a possible delayed wound healing, critical colonization and infection of wounds present a problem for surgeons. Colonized and infected wounds are a potential source for cross-infection. Molndal technique of wound dressing has proven to be effective in prevention of infection. Also the wound heal better and faster. In our study we wanted to describe the benefits of the Molndal technique wound dressing after laparoscopic cholecistectomy compared to traditional wound dressing technique. Molndal technique consisted of wound dressing with Aquacel Ag--Hydrofiber (ConvaTec, Dublin, Ireland). Traditional technique was performed using gauze compresses and hypoallergic adhesives. We analyzed the results of 100 patients after laparoscopic cholecystectomy. 50 patients were treated by Molndal technique and 50 patients by the traditional technique of wound dressing. In the group treated by Molndal technique only 1 (2%) patient has revealed a wound infection, proven by positive microbiological examination and suppuration, mostly in the subumbilical incision. In the traditional technique group 7 (14%) patients developed wound infection also predominantly in the subumbilical incision. The difference was statistically significant (p < 0.01). Our results are clearly showing that Molndal technique is effective in preventing the infection of subumbilical incision wound and is to by recommend for regular use at designated site after laparoscopic cholecistectomy.

Measurement of tooth extraction forces in upper incisors.

A new method, applied for the first time in this research, was used for measurement of tooth extraction forces. The research has been done in a group of 50 examinees to whom the tooth extraction has been done with lower premolar forceps - forceps "13" and in the control group of 54 examinees in whom the tooth extraction has been done with upper incisive forceps - forceps "1". The measurement instrument registered the extraction forces values in both types of forceps. There was no difference in any parameters in these two groups except in used pressure. While using the forceps "13", a significantly lower tooth extraction force was measured than the force measured while using the forceps "1" (p < 0.001). This means that in clinical work we can already apply noticeably less force using the lower premolar forceps for the extraction of the upper incisors (in the moments of rotation up to 70%). These results are meaningful, because they lead to better and improved instrument solutions and working techniques.