Ubiquitination of inducible nitric oxide synthase is required for its degradation

Inducible nitric oxide synthase (iNOS) is responsible for nitric oxide (NO) synthesis from l-arginine in response to inflammatory mediators. We have previously shown that iNOS is degraded through the 26S proteasome. Targeting of proteins for proteasomal degradation may or may not require their covalent linkage to multiubiquitin chains (ubiquitination). In addition, ubiquitination of a protein can serve functions other than signaling proteolysis. In this context, it is not known whether iNOS is subject to ubiquitination or whether ubiquitination is required for its degradation. In this study, we show that iNOS, expressed in HEK293 cells or induced in primary bronchial epithelial cells, A549 cells, or murine macrophages, is subject to ubiquitination. To investigate whether iNOS ubiquitination is required for its degradation, HEK293T cells were cotransfected with plasmids containing cDNAs of human iNOS and of the dominant negative ubiquitin mutant K48R. Disruption of ubiquitination by K48R ubiquitin resulted in inhibition of iNOS degradation. ts20 is a mutant cell line that contains a thermolabile ubiquitin-activating enzyme (E1) that is inactivated at elevated temperature, preventing ubiquitination. Incubation of ts20 cells, stably expressing human iNOS, at the nonpermissive temperature (40 degrees C) resulted in inhibition of iNOS degradation and marked accumulation of iNOS. These studies indicate that iNOS is subject to ubiquitination and that ubiquitination is required for its degradation.     

Patients with the most advanced rheumatoid arthritis remain with Th1 systemic defects after TNF inhibitors treatment despite clinical improvement

Systemic immune defects might reflect severely dysregulated control of chronic inflammation related to disease progression. Th17/Treg cell imbalance has been demonstrated to be involved in rheumatoid arthritis (RA) pathogenesis. Despite controversial results, a growing anti-inflammatory role in this process has been recently attributed to Th1 responses. The aim of the study was to estimate the extent of Th1/Th17/Treg imbalance in peripheral blood (PB) of patients with short- and long-term RA in relation to cytokine milieu and its reversal after therapy with methotrexate and/or TNF inhibitors, respectively. Patients with different duration of RA (median 6 vs. 120 months) in the active phase of RA were enrolled in this study. We performed flow cytometric analysis of PB Th1, Th17, and Treg populations together with estimation of serum cytokine concentrations using cytometric bead array. Disease activity was calculated on the basis of clinical and biochemical indices of inflammation (DAS28, ESR, CRP). All parameters were measured and correlated with each other before and after 6 months therapy. Elevated levels of circulating Th17 cells and IL-6 were found in all active patients, of which Th17 cells were down-regulated by the treatment. Significantly reduced Th1 and functional CTLA-4+ Treg cell frequencies as well as Th1 cytokines observed only in progressive RA seemed to be irreversible. Although therapy induced clinical improvement in almost all patients, those with advanced RA remained with signs of inflammation. Our report demonstrates that both the extent of systemic immune abnormalities and their restoration are dependent on duration of the active RA.     

Clinical and epidemiological features of Guillain‐Barré syndrome in the Western Balkans

The aim of this study was to define features of Guillain‐Barré syndrome in a large cohort of patients from three Western Balkans countries. Data from adult Guillain‐Barré syndrome (GBS) cases from 2009 to 2013 were retrospectively obtained from all tertiary health care centers. During the 5‐year period, 327 new cases of GBS were identified with a male to female ratio of 1.7 : 1. The most common GBS variants were demyelinating (65%) and axonal (12%). At nadir 45% of patients were chair‐bound, confined to bed, or required assisted ventilation, while 5% died. The crude incidence of GBS in Serbia and Montenegro was 0.93 per 100,000 population, and age‐adjusted incidence according to the world standard population was 0.86 per 100,000. Incidence was particularly high in 50‐ to 80‐year‐old men. Statistically significant seasonal variations of GBS were not observed. This study of patients with GBS in the Western Balkans allows us to prepare the health system better and to improve the management of patients. This study also opens opportunities for international collaboration and for taking part in the multinational studies on GBS.     

Tricho-rhino-phalangeal syndrome in a 13-year-old girl with chronic renal failure and severe growth retardation

Introduction: The tricho-rhino-phalangeal syndrome type III (TRPS III) is a rare autosomal dominantly inherited condition. The main clinical features are sparse and slow-growing hair and nails, a pear-shaped nose with a bulbous tip, elongated and flat philtrum, thin upper lip, cone-shaped epiphyses of the phalanges, and short stature. All patients have a point mutation in the TRPS1 gene. Case report: In this paper, we present a 13-year-old female with the typical clinical features of TRPS III, extreme growth retardation, severe deformities of both proximal radii resulting in limited extension of the elbows, and chronic renal failure (CRF) in addition. Molecular diagnostics revealed a missense mutation in exon 6 of TRPS1 that she inherited from her father who is also affected with TRPS III, but does not have CRF. In the index patient, the CRF was found to be due to bilateral renal hypodysplasia (RHD). Conclusion: Beside the renal dysplasia, the girl had severe deformities of the proximal radii – findings which have not been reported so far in TRPS III.     

Adherence to transition guidelines in European paediatric nephrology units

Background

There is increasing focus on the problems involved in the transition and transfer of young adult patients from paediatric to adult renal units. This situation was addressed by the 2011 International Pediatric Nephrology Association/International Society of Nephrology (IPNA/ISN) Consensus Statement on transition.

Methods

We performed a survey of transition practices of 15 paediatric nephrology units across Europe 2 years after publication of the consensus statement.

Results

Two thirds of units were aware of the guidelines, and one third had integrated them into their transition practice. Forty-seven per cent of units transfer five or fewer patients with chronic kidney disease (CKD) stage 5 per year to a median of five adult centres, with higher numbers of CKD stages 2–4 patients. Seventy-three per cent of units were required by the hospital or government to transfer patients by a certain age. Eighty per cent of units commenced transition planning after the patient turned 15 years of age and usually within 1–2 years of the compulsory transfer age. Forty-seven per cent of units used a transition or transfer clinic. Prominent barriers to effective transition were patient and parent attachment to the paediatric unit and difficulty in allowing the young person to perform self-care.

Conclusions

Whereas awareness of the consensus statement is suboptimal, it has had some impact on practice. Adult nephrologists receive transferred patients infrequently, and the process of transition is introduced too late by paediatricians. Government- and hospital-driven age-based transfer policies distract focus from the achievement of competencies in self care. Variable use of transition clinics, written patient information and support groups is probably due to economic and human-resource limitations. The consensus statement provides a standard for evolving and evaluating transition policies jointly agreed upon by paediatric and adult units.     

Association of the thickness of carotid intima-media complex and ancle brachial index with coronary disease severity

Abstract

Our aim was to establish the association of carotid intima-media thickness (CIMT) and ankle-brachial index(ABI) with the severity of coronary artery dissease (CAD). The study enrolled 150 examinees and divided them into two groups. The patients with stenotic changes in the coronary artery, constituted the first group (CP)(n=100); the second group consisted of the examinees without CAD — control goup (CG) (n=50). The following methods were used in the study: Color Doppler sonography of the carotid arteries, ABI, calculation of SCORE risk and coronary angiography.

Results

The number of coronary blood vessels affected by atherosclerosis was significantly higher with the increase of CIMT, CV risk score, and waist-hip ratio by one measurement unit: CIMT by 0.729; p<0.05; CV risk score by 0.033; p<0.05; and waist-hip ratio by 3.182; p<0.01. With each increase of ABI value by one measurement unit, the number of involved blood vessels dropped by 0.844; p<0.05.

Conclusions

Our results demonstrated that reduced ABI value, increased CIMT and number of plaques in the carotid arteries were in correlation with the severity of coronary artery disease.     

Current knowledge on autoantigens and autoantibodies in psoriasis

In the past decades, clinical and experimental evidence has demonstrated that psoriasis is an immune-mediated inflammatory disease of the skin that occurs in genetically susceptible individuals. Psoriasis also shows clear autoimmune pathomechanisms, but specific cellular targets for the onset and maintenance of psoriatic lesions were not established until 2014. Since then, four psoriasis autoantigens were discovered, namely cathelicidin LL-37, melanocytic ADAMTSL5, lipid antigen PLA2G4D and keratin 17. Autoreactive T cells against these autoantigens were found in a number of patients with moderate-to-severe plaque psoriasis. Moreover, the discovery of autoantibodies against LL-37 and ADAMTSL5 and their strong association with psoriatic arthritis (PsA) suggest a potential role of these autoantibodies in the pathogenesis of PsA. This review discusses the current studies on psoriatic autoantigens and the associated circulating autoantibodies and their mechanisms involved in the development and maintenance of psoriatic plaques. Recent autoimmune evidence fuelled the discussion on psoriasis as an autoimmune skin disorder and has the potential to develop new treatment strategies with protective and therapeutic antigen-targeted methods.