The review discusses some of the causes of proteinuria in nephrotic syndrome due to extrarenal mechanisms. Autoantibodies identified in recent years are involved in the violation of the selective permeability of the filtration barrier in membranous nephropathy. The direct relationship between the level of hyperglycemia and proteinuria in diabetic nephropathy is analyzed. The role of reactive oxygen species, end products of glycation, angiotensin II, transforming growth factor β-1, epithelial-mesenchymal transformation of podocytes, Rho GTPases, intracellular signaling pathway mTOR, Wnt/β-catenin signaling cascade is emphasized. Particular attention is paid to the problem of searching and identifying circulating permeability factors in the pathogenesis of idiopathic nephrotic syndrome in patients with minimal changes and focal segmental glomerulosclerosis: vascular permeability factor (VPF), vasodilator-stimulated phosphoprotein (VASP), soluble hemopexin (Hpx) receptor-receptor-receptor type (suPAR), cardiotropin-like cytokine-1 (CLCF-1) and anti-CD40 antibodies. It is noted that the role of such factors is not in doubt today, however, from the standpoint of evidence-based medicine, this role needs serious confirmation by specially formulated criteria.

Uromodulin (UMO) is a multifunctional glycoprotein expressed in the epithelial cells of the thick ascending part of the loop of Henle. Currently a lot of data about mechanisms of biosynthesis, apical and basolateral transport of UMO, changes in urine and blood concentrations in different kidney compartments damage, roles of UMO in protecting kidneys from infections, maintaining mineral homeostasis, development of arterial hypertension and the participation of this glycoprotein in other physiological and pathological processes has been accumulated. The article discusses the clinical significance of UMO in the development and progression of chronic kidney disease, prognostic value of UMO urine and blood concentrations in terms of the risk of cardiovascular diseases and probability of acute kidney damage in patients with cardiovascular pathology. Briefly highlights issues of UMO gene mutation and development of autosomal dominant tubulointerstitial kidney disease.

BACKGROUND. Oxidative status impairment plays a significant role in the pathogenesis of SLE and lupus nephritis (LN). The data about oxidative status in this disease are incomplete, that’s why it’s necessary to use a new approach to study it. 

THE AIM: To study oxidative status in SLE patients with kidney involvement. 

PATIENTS AND METHODS:53 patients with SLE were included in this prospective study, among them 40 patients with different severity of kidney involvement, control group were 87 healthy donors. Oxidative stress parameters were measured: antioxidant activity (AOA) of blood plasma and parameters, characterizing the state of the main source of reactive oxygen species (ROS) – neutrophils, more specifically: specific spontaneous neutrophil activity, specific stimulated activity (peak and integral), coefficient of respiratory burst attenuation, representing the rate of free radical production decrease after stimulation, the higher the value of this parameter, the slower is free radical production decrease. 

RESULTS. It was shown elevation of neutrophil free radical-producing activity parameters and elevation of blood plasma AOA in patients with LN, comparing to healthy controls. Immunosuppressive therapy with glucocorticosteroids (GCS) and cytostatics (CS) increased blood plasma AOA comparing to monotherapy with GCS. A correlation between oxidative status impairment and intensity of inflammatory reactions was found: correlation of respiratory burst attenuation coefficient with blood sedimentation rate was shown. Reduction of spontaneous free radical-producing neutrophil activity was found in LN patients with NS, which might be the result of neutrophil functional activity attenuation in high disease activity. 

CONCLUSION. The increased free radical-producing neutrophil activity was shown, which might be the cause of oxidative stress in SLE with LN. It seems warranted investigation of these parameters in samples of larger volume to search targets aimed at neutrophils. The necessity of antioxidant therapy in patients with SLE seems doubtful, as they show significant increase of blood plasma AOA, which might result from compensatory reaction of human organism to oxidative stress and therapy with GCS and CS.

THE AIM: To study the characteristics of phosphorus-calcium metabolism in patients with neurogenic disorders of urination, taking into account the severity of the manifestations of connective tissue dysplasia. 

PATIENTS AND METHODS. The study included 90 children, including 60 children with neuro-muscular dysfunction of the bladder (NMDB) and 30 children with enuresis from the age of 5 to 15 years. The diagnosis was established based on a comprehensive examination and according to industry standards. Connective tissue dysplasia was diagnosed in children with the detection of 6 or more small external or visceral manifestations involving 3 or more organs from different systems. Assessment of the severity (severity) of connective tissue dysplasia was carried out according to the point system proposed by T.I. Kadurina et al. Each group was divided into subgroups depending on the severity of the manifestations of connective tissue dysplasia. The determination of the level of calcium and phosphorus in the blood and urine, as well as the calculation of the calcium-creatinine coefficient followed by a comparison of the results in these groups and subgroups. To assess the significance of differences, the Mann-Whitney test was calculated, p <0.05 was considered significant. 

RESULTS. he level of calcium and phosphorus in the urine was slightly higher in children with enuresis, especially in the morning portion of urine, where the concentration of calcium was 26% higher than in patients with NMDB. At the same time, the value of calcium /creatinine coefficient was significantly higher in the group of patients with enuresis and was 2 times higher than the normative indicators, which indicates the importance of hypercalciuria in the development of enuresis.

 СONCLUSION. According to the obtained data, the severity of calciuria, determined by the value of the calcium-creatinine coefficient, is significantly higher in patients with enuresis than with NMDB.

Insulin resistance (IR) is defined as a violation of the biological response to stimulation of the heart, skeletal muscle, liver, and adipose tissue. The reasons for the formation of the syndrome are diverse, and clinical diagnosis is difficult since there is no generally accepted test available to determine it. For the diagnosis of IR directly and indirectly developed test groups. The complexity of their implementation in some cohorts of patients led to the development of a number of glycemic indices. However, no consensus has yet been reached on which one should be preferred. 

THE AIM: to compare IR screening methods in a cohort of hemodialysis patients. 

PATIENTS AND METHODS. 124 patients were examined, including 66 men and 58 women aged 57.6 ± 13.6 years, receiving HD treatment for 75.4 ± 44.5 months. For the screening of IR, the HOMA-1 and HOMA-2 glucose homeostasis model, QUICKI index, and triglycerides/glucose (TriH) were used. 

RESULTS. When conducting a nonparametric correlation analysis for fasting insulin plasma concentrations, statistically significant relationships were revealed only in men: with BMI (Rs = 0.258 p = 0.049), waist circumference to height ratio (Rs = 0.316 p = 0.015), and amount of dietary protein (Rs = 0.271 p = 0.039), systolic blood pressure (Rs = 0.308 p = 0.018), diastolic blood pressure (Rs = 0.290 p = 0.027), C-reactive protein level (Rs = 0.579 p = 0.0001). In women, no statistically significant correlations were found. The value of the Charlson index, as well as tobacco smoking, currently or in the history of the indicators of insulin resistance had no effect. According to the results of logistic regression analysis, the risk of developing clinical manifestations of atherosclerotic lesions of any vascular pool increased by 4.5 times (χ2 = 4.582 p = 0.032) with IR in the HOMA-1 model of more than 2.7 units, however, only in men. The relationship of other indicators of IR with atherosclerosis was not identified. 

CONCLUSION. A comparison of surrogate models of IR, from our point of view, allows us to distinguish HOMA-1 and HOMA-2. Probably, for the cross-sectional studies it is advisable to use the first of them, and for longitudinal – the second.

BACKGROUND. The lack of data on the epidemiology of presarcopenia/sarcopenia leads to an underestimation of the role of this condition in the structure of morbidity and mortality of haemodialysis patients in theRussian Federation. 

THE AIM: to study the epidemiological aspects of presarcopenia /sarcopenia in patients with chronic kidney disease stage 5d. 

PATIENTS AND METHODS. This study comprised 317 patients receiving programmed bicarbonate haemodialysis for 8.2 ± 5.1 years, among them 171 women and 146 men, the average age was 57.1 ± 11.3 years. The assessment of the presence of sarcopenia was performed using the method recommended by the European Working Group on Sarcopenia in Older People. 

RESULTS. The prevalence of presarcopenia was 0.7 % and sarcopenia 29.6 %. The incidence of skeletal muscle mass deficiency according to muscle mass index (IMM) was 30.3 %, 48.7 % showed a decrease in muscle strength according to dynamometry, and low performance of skeletal muscles according to 6 minute walk test was determined in 42.8 %. Sarcopenia patients were significantly characterized by lower body mass index, as well as higher body fat mass values. The duration of haemodialysis (χ2 = 22.376, p = 0.0001) and the patient's age (χ2 = 10.545 p = 0.014) were an independent risk factors for the development of sarcopenia. 

CONCLUSION. Sarcopenia is recorded more frequently in hemodialysis patients than presarcopenia. Its prevalence increases among patients of older age groups and with a hemodialysis duration of more than 5 years. The age and experience of dialysis make their independent contribution to the development of this syndrome.

(Project, 2019)

This article is the continuation of analysis and discussion from the book by Professor AI Nevorotin "Matrix phraseological collection: a manual for writing a scientific article in English". The Matrix phraseological collection is a kind of catalog of text samples. The samples were from articles selected from the leading English-language scientific journals and were systematized in such a way that when writing an article in English, a Russian researchers are able easy to find examples suitable for his/her own work. Furthermore, the selected samples can be transformed accordingly saving the semantic and syntactic relations between the elements and, finally, be inserted into the text. Part 3 of the book is devoted to a detailed analysis of the relevance of the scientific problem under consideration. Besides, a detailed fool description of the study goal is presented. Just this section finalizes of the chapter "Introduction". In the following rather big section, presents the optimal recommended way for the description of results.