The effect of bariatric surgery on purine metabolism and gout

Gout is an auto-inflammatory tophaceous disease characterized by the deposition of crystals of monosodium urate and developing in connection with this inflammation in people with hyperuricemia (HU). Except to genetic factors, risk factors for the development of HU and gout are many modifiable factors, including metabolic syndrome and obesity, and their correction is the most important component of successful disease control. Obesity can change the clinical picture of gout, characterized by an earlier onset, a large number of affected joints. Weight loss helps reduce uric acid (UA) serum levels. Bariatric / metabolic surgery significantly reduces the incidence of comorbid obesity and mortality, and is by far the most effective way to combat obesity. In addition to improving health, an important goal of bariatric surgery is to improve the quality of life. Bariatric surgery can prevent the development of HU in subjects with an initially normal level of serum UA before surgery. The dynamics of the concentration of UA in serum can be a predictor of successful bariatric surgery and help in predicting the severity of postoperative weight loss. The decrease in body weight after bariatric surgery leads to a decrease in UA in the long-term postoperative period, however, there is a high frequency of acute gout attacks in the early postoperative period. Thus, bariatric surgery has a significant effect on HU and gout and can be an effective treatment for this disease

Menopause and premature ovarian insufficiency in rheumatic diseases: A review

Premature ovarian insufficiency (POI) is a clinical syndrome defined as loss of ovarian function before the age of 40 years. Among the causes of POI are genetic, metabolic disorders, as well as infectious or iatrogenic factors, but in some cases the exact cause cannot be established. Given the possible association of ovarian failure with autoimmune disorders, as well as the detection of antibodies to normal ovarian tissue in the serum of patients with POI, it is assumed that an autoimmune mechanism is a significant cause of the syndrome. Taking into account the relationship between POI and autoimmune diseases, it seems relevant to address the issues of mutual influence of the ovarian function of women with POI and rheumatic diseases (in particular, systemic lupus erythematosus, rheumatoid arthritis and systemic scleroderma), which is presented in this review. Hormone replacement therapy may be recommended for women with POI to improve their quality of life. Keywords: premature ovarian insufficiency, menopause, anti-ovarian antibodies, systemic lupus erythematosus, rheumatoid arthritis, systemic scleroderma, rheumatic diseases, hormone replacement therapy

Urate-lowering effects of dipeptidyl peptidase-4 inhibitors

Hyperuricemia is an increase of uric acid (UA) concentration in blood serum >420 pmol/L in men or >360 pmol/L in women and is considered to be a common biochemical abnormality. This condition shows that the extracellular fluid is oversaturated with urates, which concentration exceeds the limit of their solubility. This fact predisposes to the formation of crystals of sodium salt of UA and results in gout, urolithiasis, and other diseases. The frequent combination and relationship between purine and carbohydrate metabolism were noted in previous studies. In this regard, the choice of drugs for correcting these disorders should consider the possibility of a combined positive effect on the UA and serum glucose levels. The hypoglycemic drugs with pleiotropic effects on several metabolic syndrome components are considered to be of particular interest. Currently, one of the most frequently prescribed groups of drugs in the treatment of diabetes mellitus type 2 are dipeptidyl peptidase-4 inhibitors, which affect the level of incretins (gliptins). These drugs can be potentially attractive in patients with purine metabolism disorders since the available data indicate that these drugs affect UA level

Helicity-dependent photocurrents in graphene layers excited by mid-infrared radiation of a CO2_2-laser

We report the study of the helicity driven photocurrents in graphene excited by mid-infrared light of a CO$_2$-laser. Illuminating an unbiased monolayer sheet of graphene with circularly polarized radiation generates -- under oblique incidence -- an electric current perpendicular to the plane of incidence, whose sign is reversed by switching the radiation helicity. We show that the current is caused by the interplay of the circular $ac$ Hall effect and the circular photogalvanic effect. Studying the frequency dependence of the current in graphene layers grown on the SiC substrate we observe that the current exhibits a resonance at frequencies matching the longitudinal optical phonon in SiC

Assessment of the risk of developing type 2 diabetes mellitus in patients with gout based on the FINDRISС scale

BACKGROUND: Gout is associated with a high incidence of type 2 diabetes mellitus (T2DM).AIM: To calculate the risk of T2DM on the FINDRISС scale, to assess the sensitivity and specificity of the scale in patients with gout based on the results of prospective follow-up.MATERIALS AND METHODS: A prospective single-center study included 444 patients with gout over 18 years of age (49 women, 395 men) without diabetes. The duration of follow-up ranged from 2 to 8 years. Initially, the risk of developing diabetes mellitus 2 was calculated according to the Russian version of the FINDRISС scale. The risk of developing T2DM was assessed as «low» with a total score (CC) <7 points, slightly increased — from 7 to 11 points, moderate — from 12 to 14 points, high — from 15 to 20 points, and very high — ≥20 points. To assess the validity of using the FINDRISС scale, an analysis of sensitivity, specificity, construction of the ROC curve with the determination of the area under the curve was carried out. The presence and number of subcutaneous tophi, the number of arthritis attacks over the last year, the number of affected joints during the illness, serum levels of creatinine, uric acid, hs-CRP, glycated hemoglobin were determined.RESULTS: Over 5.66 [2.69; 7.64] years of follow-up, T2DM developed in 108 patients (24.3%). On the FINDRISС scale, low risk was found in 16 (4%), slightly increased in 187 (42%), moderate in 98 (22%), high in 80 (18%), very high in 63 (14%). The most common risk factors (RF) for T2DM included in FINDRISС were BMI> 25 kg / m2  — 85.6% of patients, taking antihypertensive drugs — 81.3% of patients, age over 45 years in 70.5% of patients. The sensitivity and specificity of the FINDRISС scale were 52.8% and 66.3%, respectively. According to these data, the quality of the model was assessed as moderate. 9% vs 31.1% (p = 0.014)), serum MK level ≤300 μmol / L. Developed type 2 diabetes 33.3% of patients with moderate / high / very high risk 18.1% of patients with low or slightly increased risk (p = 0.0002).CONCLUSION: The FINDRISС scale can have sufficient sensitivity (52.8%) and specificity (66.3%) and can be used to calculate the risk of T2DM in patients with gout

Impurity breakdown and terahertz luminescence in n-GaN epilayers under external electric field

We report on the observation and experimental studies of impurity breakdown and terahertz luminescence in n-GaN epilayers under external electric field. The terahertz electroluminescence is observed in a wide range of doping levels (at noncompensated donor density from 4.5×10[sup 16] to 3.4×10[sup 18] cm[sup −3]). Spectra of terahertz luminescence and photoconductivity are studied by means of Fourier transform spectrometry. Distinctive features of the spectra can be assigned to intracenter electron transitions between excited and ground states of silicon and oxygen donors and to hot electron transitions to the donor states.Peer reviewe

Факторы риска развития сахарного диабета 2-го типа у пациентов с подагрой: результаты проспективного исследования

The development of type 2 diabetes mellitus (DM) (DM2) in patients with gout can be influenced by both conventional and directly linked to gout risk factors (RFs).Objective: to identify RFs for the development of DM2 in patients with gout, including those directly associated with gout, based on long-term prospective follow-up data.Patients and methods. The study included 444 patients with gout older than 18 years (49 women, 395 men) who did not have DM. The followup period ranged from 2 to 8 years. The studied RFs for DM2 were: gender, age, family history of DM2, obesity, alcohol consumption >20 units per week, insufficient physical activity, unbalanced nutrition, history of hyperglycemia, coronary heart disease (CHD), arterial hypertension (AH), chronic heart failure, antihypertensive drugs, diuretics, glucocorticoids (GCs), urate-lowering therapy, serum levels of cholesterol, triglycerides, CRP, uric acid (UA), glucose, creatinine, glomerular filtration rate <60 ml/min/1.73 m2, the presence of tophi, >4 attacks of gout per year, ≥5 affected joints during the disease.Results and discussion. DM2 developed in 108 (24.3%) patients. These patients were older, had a family history of DM, more often received antihypertensive therapy, diuretics, and glucocorticoids (49.1; 73.1; 27.8 and 47.2%, respectively) than patients who did not develop DM2 (25.6; 50.5; 14.8 and 36.4%, respectively; p<0.05 for all cases). In addition, patients with DM2 were more likely to have subcutaneous tophi (59.3% versus 30.0%; p=0.001), among them there were more individuals (67.6% versus 31.6%; p=0.001) with frequent attacks of arthritis (>4 attacks per year). UA levels >480 and 600 μmol/l were also significantly more frequent (p=0.0002) in patients with DM2 (71.3 and 34.3%, respectively).According to logistic regression data, factors that increase the risk of developing DM2 were: family history of DM, a history of hyperglycemia, CHD, AH, intake of GCs, antihypertensive drugs, the presence of tophi, >4 exacerbations of gout per year. Febuxostat use and UA <300 μmol/L were associated with a lower risk of DM2.Conclusion. The occurrence of DM2 in gout is associated not only with well-known risk factors, but also with hyperuricemia and microcrystalline inflammation. Febuxostat therapy is associated with a lower risk of developing DM2.На развитие сахарного диабета (СД) 2-го типа (СД2) у пациентов с подагрой могут влиять как общепринятые, так и непосредственно связанные с подагрой факторы риска (ФР).Цель исследования – на основании данных многолетнего проспективного наблюдения выявить у пациентов с подагрой ФР развития СД2, в том числе непосредственно связанные с подагрой.Пациенты и методы. В исследование включено 444 пациента c подагрой старше 18 лет (49 женщин, 395 мужчин), не имевших СД. Длительность наблюдения составляла от 2 до 8 лет. В качестве ФР СД2 рассмотрены: пол, возраст, отягощенная наследственность по СД2, ожирение, употребление алкоголя >20 ед. в неделю, недостаточная физическая нагрузка, несбалансированное питание, гипергликемия в анамнезе, ишемическая болезнь сердца (ИБС), артериальная гипертензия (АГ), хроническая сердечная недостаточность, прием гипотензивных препаратов, диуретиков, глюкокортикоидов (ГК), уратснижающая терапия, сывороточные уровни холестерина, триглицеридов, СРБ, мочевой кислоты (МК), глюкозы, креатинина, скорость клубочковой фильтрации <60 мл/мин/1,73м2, наличие тофусов, >4 приступов подагры в год, ≥5 пораженных суставов за время болезни.Результаты и обсуждение. СД2 развился у 108 (24,3%) пациентов. Эти пациенты были старше, имели отягощенную наследственность по СД, чаще получали антигипертензивную терапию, диуретики и ГК (49,1; 73,1; 27,8 и 47,2% соответственно), чем больные, у которых СД2 не возник (25,6; 50,5; 14,8 и 36,4% соответственно; р<0,05 для всех случаев). Кроме того, у пациентов с СД2 чаще выявлялись подкожные тофусы (59,3% против 30,0%; р=0,001), среди них было больше лиц (67,6% против 31,6%; р=0,001) с частыми приступами артрита (>4 приступов в год). Уровни МК >480 и 600 мкмоль/л также значимо чаще (р=0,0002) определялись у больных с СД2 (71,3 и 34,3% соответственно).По данным логистической регрессии, факторами, увеличивающими риск возникновения СД2, были: наследственная отягощенность по СД, наличие гипергликемии в анамнезе, ИБС, АГ, прием ГК, гипотензивных препаратов, наличие тофусов, >4 обострений подагры в год. Прием фебуксостата и уровень МК <300 мкмоль/л ассоциировались с меньшим риском развития СД2.Заключение. Возникновение СД2 при подагре связано не только с общеизвестными ФР, но и с гиперурикемией и микрокристаллическим воспалением. Терапия фебуксостатом ассоциируется с меньшим риском развития СД2

Postoperative diagnostics case of the patient with kidney canсer metastasis in the thyroid gland in combination with left internal jugular vein thrombosis

We present a clinical case of the 68-years-old woman with complaints of enlarged neck, more pronounced at the left side and sore throat. In the course of ultrasound examination, conglomerate mass in left of thyroid gland was revealed. More than that, in the lumen of the internal jugular vein the formation of an average echogenicity was found. Following fine-needle aspiration biopsy revealed signs of colloid struma (Bethesda II). The patient underwent left-sided hemithyroidectomy. Atrevision while the operation the left thyroid gland is enlarged in the size due to the nodal formation spreading to the left angle of the lower jaw and locating retrosternal and behind trachea. Postoperative histological examination revealed metastasis of kindey cancer in the left thyroid gland with the signs of invasive growth to surrounding vessels and muscles