Filtration Fraction Research Articles

Blood Pressure and Renal Responses to Orthostatic Stress Before and After Radiofrequency Renal Denervation in Patients with Resistant Hypertension.

Background/AimsIn patients with resistant hypertension, renal denervation (RDN) studies have mainly focused their outcomes on blood pressure (BP). The aim of this study was to evaluate the long-term effect of RDN on neurohormonal profiles, renal hemodynamics and sodium excretion in a resting state and during stress induced by lower body negative pressure (LBNP).Materials and methodsThis was a single center prospective observational study. Norepinephrine, plasma renin activity (PRA), glomerular filtration rate (GFR), renal plasma flow (RPF) and sodium excretion were measured in unstimulated conditions (rest) and after one hour of LBNP at three different time points: before (M0), one (M1) and twelve months (M12) after RDN.ResultsThirteen patients with resistant hypertension were included. In the resting state, no differences were observed in norepinephrine, PRA, sodium excretion and mean BP levels after RDN. GFR (78 ± 32 ml/min at M0 vs 66 ± 26 ml/min at M12 (p = 0.012) and filtration fraction (22.6 ±5.4% at M0 vs 15.1 ±5.3% at M12 (p = 0.002)) both decreased after RDN. During LBNP, the magnitude of the mean BP increase was reduced from +6.8 ± 6.6 mm Hg at M0 to +2.3 ± 1.3 mm Hg at M12 (p = 0.005). The LBNP-induced increase in norepinephrine and decrease in GFR and sodium excretion observed before RDN were blunted after the procedure.ConclusionA decrease in GFR and filtration fraction was observed one year after RDN. In addition, our results suggest that RDN blunts not only the norepinephrine but also the mean BP, the GFR and the sodium excretion responses to an orthostatic stress one year after the intervention.Registry numberNCT01734096

Identification of In-Vitro Red Fluorescent Protein with Antipathogenic Activity from the Midgut of the Silkworm (Bombyx Mori L.).

The midgut of silkworm (Bombyx mori L.) plays an important role as a natural barrier and source of innate immunity. We had purified the novel red fluorescent protein (RFP) from the midgut of the silkworm Bombyx mori L. and bioassay studies confirmed RFPs possess antiviral, antifungal and antibacterial properties. N-terminal sequence of RFP analysis predicted chbp gene and it belongs to lipocalin gene family and is known to involve in anti-pathogenic activities. The main objective of this study was to purify RFP from the midgut of Kolar Gold silkworm and confirm its antimicrobial activity. For isolation of RFP, midgut juice was collected by brief exposure to chloroform vapours to fifth instar Kolar Gold silkworm larvae. Juice was purified by 40 % ammonium sulfate precipitation and purified by gel filtration chromatography (GFC) and fractions with fluorescence red under Ultra violet (UV) were collected. Molecular weight and purity of RFP was identified using PAGE, MALDI-TOF and HPLC. Antimicrobial property of purified RFP against BmNPV, Escherichia coli, Klebsiella pneumonia, Bacillus subtilis and Phytophthora meadii was performed. N-terminal sequencing of RFP was performed using Edman degradation method. Using ten amino acid sequence, using default parameter BLAST search was performerd. From the fifth day old fifth instar silkworm midgut mRNA was isolated and cDNA was synthesized using oligo-dt primer and amplification of ChBP gene was carried out by using cDNA as the template and ChBP gene specific primers. chbp protein sequence as a input built the homology model by using SWISS-MODEL. RFP was purified by 40 % ammonium sulfate precipitation and gel filtration chromatography (GFC) and fractions with fluorescence red under Ultra violet (UV) were collected and SDS - PAGE revealed a size of 40 kDa. RFP purified by GFC was further reconfirmed by HPLC with a single peak with a retention time of 8.755 min. MALDI-TOF produced a peak at a molecular mass of 40 kDa. RFP from the midgut juice showed antiviral activity against the silkworm virus BmNPV, antibacterial activity against Escherichia coli, Klebsiella pneumonia, Bacillus subtilis and Phytophthora meadii. N-terminal sequencing of RFP by Edman degradation method sequenced TQTIETDYWV amino acids and BLAST analysis predicted the Chlorophyllide-a Binding Protein (chbp) with B. mori. PCR product was sequenced and obtained 911bp nucleotides encoding 302 amino acid residues and deposited with the accession number KX186723 in NCBI. Sequence analysis revealed Chbp belongs to lipocalin gene family and known to involve in antiviral, antifungal and anti-bacterial properties. Chbp gene homology model was predicted using crystal structure of insecticyanin A from the tobacco hornworm as a template. Our results indicated RFP present in midgut juice of 5th instar larvae of kolar gold silkworm. We have purified novel RFP with molecular mass of 40 kDa and showed its antipathogenic activities. Chbp gene synthesises RFP and further it could be utilized for agriculture and pharmaceutical industry.

The indoor-outdoor characteristics of water-soluble ion in PM2.5 in Tianjin wintertime.

The indoor and outdoor PM2.5 mass concentration, water-soluble ion by filter sampler was analyzed on December 3-21, 2015 during wintertime in Tianjin, China. The results indicate that high humidity conditions result in the accumulation of atmospheric pollutants and reduce atmosphere visibility. The I/O ratio for PM2.5 concentration in dormitory and lab are less than 1 in haze days. Indoor PM2.5 concentration increases rapidly with outdoor PM2.5 concentration increasing in haze days. The filtration factors of the dormitory and lab indicate nearly half of the outdoor PM2.5 enters indoor environment. The human activities in dormitory could cause more the formation of PM2.5 than those in lab. The concentration of SO42- is the highest ion in water-soluble ion for outdoor PM2.5. The SO42-, NO3-, NH4+, and Cl- are generated mainly by outdoor sources; however, the Na+, Ca2+, and Mg2+ are generated mainly by indoor sources. The NH4NO3, (NH4)2SO4, and NH4Cl accounts for 20.2~41.8%, 32.0~51.4%, and 6.4~10.6% of the total water-soluble ion in different indoor-outdoor environment. The total secondary aerosols including NH4NO3, (NH4)2SO4, and NH4Cl in PM2.5 are 28.3, 42.1, 28.2, 31.0, and 33.9% in outdoor environment for haze days, outdoor environment for non-haze days, dormitory for haze days, dormitory for non-haze days, and lab for haze days, respectively.

ANTITOXIC AND NEPHROPROTECTIVE ACTION OF "POLYPHITOL-1" PHYTO-COMPOSITION IN CASE OF CADMIUM INTOXICATION IN YOUNG NOT SEXUALLY MATURE RATS

Abstract. Under conditions of increasing pollution of the environment medical and biological studies related to prophylaxis and treatment of adverse influence of ecotoxicants in respect to age are of great importance. Young organism is especially sensitive to the influence of toxic agents because of the insufficient development of the main regulatory systems, imperfection of mechanisms of protection, low adaptability, and morphological and functional characteristics of the organism.Objective - to study protective influence of the phytopreparation Polyphitol-1 on the total toxicity and functional status of kidneys under conditions of experimental cadmium toxicosis in young not sexually mature animals.Material and methods. The study was conducted with young (5-6 weeks) juvenile male rats in the period of their growth and sexual maturation. Subchronic intoxication was induced by daily administration of cadmium chloride into the stomach for 30 days (0.03 mg/kg). Polyphitol-1 (PPh-1) was administered into the stomach at a dose of 2.5 ml/kg 2 hours before administering the dose of the metal. On the 30th day the content of cadmium ions in the organism was examined, together with indexes of excretory, ionic, and acidic regulating function of the kidneys. The intact animals of the same age, lived under the similar vivarium conditions, were used as the control.Results. It was found that the body mass of the intoxicated animals increased only 15.9% for 30 days in comparison with the initial level; this number is 3.7 times less than for the control animals. Owing to PPh-1 administration the mass of the animals increased 39.4%; this is 2.5 times higher than for the intoxicated animals. Under conditions of cadmium intoxication the most sensitive target organs, where the accumulation of cadmium turned out to be the highest, are the kidneys and liver. The content of metal cations in them grew in 17.0 and 8.6 times, respectively. Under the influence of PPh-1 the accumulation of metal in the organism of animals lowered, specifically in the liver – by a factor of 1.8, in the kidneys – by a factor of 1.7. Against a background of cadmium nephrotoxicity medical and preventive administration of PPh-1 increased diuresis by a factor of 1.3, significantly lowered proteinuria; glomerular filtration, depressed under conditions of metal toxicosis, increased by a factor of 1.9, which halved the level of creatinine in the blood plasma down to the level of the control animals. The transport of sodium ions in nephron intensified, its proximal reabsorbtion increased by a factor of 2.3. The filtration fraction of sodium ions increased by a factor of 2.2, and their excretive fraction and clearance decreased by a factor of 2,6-3,0. Also, the compromised tubular-glomerular feedback was restored.Conclusions. Medical and preventive administration of PPh-1 phytocomposition lowers the toxic influence of cadmium intoxication on the organism of young not sexually mature animals (suppresses the inhibitory influence of cadmium chloride on the physiological increase of the body mass, decreases the accumulation of cadmium ions in the organism). Administration of PPh-1 restores the rate of glomerular filtration, eliminates retention azotemia, activates the transport of sodium in the nephron, which promotes its reabsorbtion and decreases its loss by the organism. Owing to its nephroprotective action, PPh-1 normalizes the disordered excretory, ionic and acidic regulating functions of the kidneys, restores the mechanisms of glomerular-tubular and tubular-tubular equilibrium and tubular-glomerular feedback.

Urinary Peptides As a Novel Source of T Cell Allergen Epitopes.

Mouse allergy in both laboratory workers and in inner-city children is associated with allergic rhinitis and asthma, posing a serious public health concern. Urine is a major source of mouse allergens, as mice spray urine onto their surroundings, where the proteins dry up and become airborne on dust particles. Here, we tested whether oligopeptides that are abundant in mouse urine may contribute to mouse allergic T cell response. Over 1,300 distinct oligopeptides were detected by mass spectrometry analysis of the low molecular weight filtrate fraction of mouse urine (LoMo). Posttranslationally modified peptides were common, accounting for almost half of total peptides. A pool consisting of 225 unique oligopeptides of 13 residues or more in size identified within was tested for its capacity to elicit T cell reactivity in mouse allergic donors. Following 14-day in vitro stimulation of PBMCs, we detected responses in about 95% of donors tested, directed against 116 distinct peptides, predominantly associated with Th2 cytokines (IL-5). Peptides from non-urine related proteins such as epidermal growth factor, collagen, and Beta-globin accounted for the highest response (15.9, 9.1, and 8.1% of the total response, respectively). Peptides derived from major urinary proteins (MUPs), kidney androgen-regulated protein (KAP), and uromodulin were the main T cell targets from kidney or urine related sources. Further ex vivo analysis of enrichment of 4-1BB expressing cells demonstrated that LoMo pool-specific T cell reactivity can be detected directly ex vivo in mouse allergic but not in non-allergic donors. Further cytometric analysis of responding cells revealed a bone fide memory T cell phenotype and confirmed their Th2 polarization. Overall, these data suggest that mouse urine-derived oligopeptides are a novel target for mouse allergy-associated T cell responses, which may contribute to immunopathological mechanisms in mouse allergy.

Asymmetric cellulose triacetate is a safe and effective alternative for online haemodiafiltration

BackgroundIn post-dilution haemodiafiltration only synthetic membranes have been used to date. Asymmetric cellulose triacetate (ATA™) is now available, whose characteristics are suitable for this technique. ObjectivesTo describe the in vivo performance and behaviour of this membrane, to identify its depurative effectiveness, use in clinical practice and its biocompatibility, both acute and after one month of treatment. MethodsObservational prospective study of 23 patients who were dialysed for 4 weeks using an ATA™ membrane and who maintained their prior regimen. ResultsA total of 287 sessions were performed and 264 complete sessions were collected. With an effective time of 243.7 (17.6) min and a mean blood flow of 371.7 (23) ml/min, an average Kt of 56.3 (5.3) l was observed, as well as a convection volume of 27.1 (4.2) l, a filtration fraction of 29.9 (3.7) %, a urea reduction ratio (RR) of 81 (5.2) %, a creatinine RR of 74.7 (4.6) %, a β2-microglobulin RR of 76.5 (4.8) % and a retinol binding protein RR of 18.6 (7.6) %. There were no technical problems or alarms. Changing the heparin dosage was not necessary. No increases in C3a or C5a concentrations or leukopenia were observed in the first 30min of the session. Neither the monocyte subpopulations nor IL-β1 or IL-6 were significantly altered after one month of treatment. ConclusionsThe new ATA™ membrane achieves adequate Kt and convection volume, without technical problems and with good biocompatibility and inflammatory profiles. It is therefore a valid option for post-dilution haemodiafiltration, particularly in patients allergic to synthetic membranes.

Dos métodos de anticoagulación en técnicas continuas de depuración extrarrenal

Introducción: Las técnicas continuas de depuración extrarrenal son la terapia de elección en pacientes críticos. Pero, no están exentas de complicaciones como la coagulación del circuito extracorpóreo. El fármaco usado tradicionalmente para la anticoagulación, es la heparina sódica. Aunque también son empleados otros métodos de anticoagulación, como el citrato. Objetivo: Evaluar la eficacia y seguridad de dos métodos de anticoagulación en pacientes tratados con terapias continuas, en unidades de cuidados intensivos del Hospital Clínic. Material y Método: Estudio observacional, retrospectivo de 54 sujetos. Se aplicaron los criterios de Insuficiencia renal aguda, descritos en el protocolo “Guía para el tratamiento sustitutivo renal en la insuficiencia renal aguda del Hospital Clínic”. Tratados mediante hemodiafiltración, combinando terapias de convección y difusión. Con fracción de filtración < 25%, y dosis de efluente de 30 ml/kg/h. 27 sujetos realizaron hemodiafiltración, reposición pre-filtro y anticoagulación con heparina sódica. El resto, hemodiafiltración, reposición post-filtro y anticoagulación con citrato. Se valoraron episodios de sangrado y duración en horas de los circuitos extracorpóreos, durante 72 horas de terapia. Resultados: El citrato demostró una mayor supervivencia de filtros (95% IC, MD 65, 44.00-72.00 vs MD 36.00, 15.00-22.00, p=0,02). Los pacientes tratados con heparina presentaron más episodios de sangrado, sin diferencias estadísticamente significativas (95% IC, n=6 vs n=9, p=0.537). Hubo un episodio de hipocalcemia en el grupo citrato, corregido según protocolo. En el grupo heparina, no se presentaron casos de trombocitopenia inducida por heparina. Conclusiones: El presente estudio, demuestra una mayor eficacia en la supervivencia de los filtros en el grupo citrato. PALABRAS CLAVE: citrato; heparina; anticoagulación regional; terapia continua depuración extrarrenal; fracaso renal agudo.

Approximate symmetry group classification for a nonlinear fractional filtration equation of diffusion-wave type

A one-dimensional nonlinear fractional filtration equation with the Riemann–Liouville time-fractional derivative is proposed for modeling fluid flow through a porous medium. This equation is derived under an assumption that the fluid has a fractional equation of state in which the fluid density depends on the time-fractional derivative of pressure. The obtained equation belongs to the diffusion-wave type of equations. A case when the order of fractional differentiation is close to an integer number is considered, and a small parameter is introduced into the fractional filtration equation under consideration. An expansion of the Riemann–Liouville time-fractional derivative into the series with respect to this small parameter is obtained. Using this expansion, a first-order approximation of the derived fractional filtration equation is performed. Next, the problem of approximate Lie point symmetry group classification for this approximate nonlinear filtration equation with a small parameter is studied. It is shown that approximate symmetry groups admitted by different realizations of the approximate filtration equation have much more dimensions than the corresponding exact Lie point symmetry groups admitted by unperturbed fractional diffusion-wave equations. Obtained classification results permit to construct approximate invariant solutions for the considered nonlinear time-fractional filtration equations.

Experimental study of a compact electrostatically assisted air coarse filter for efficient particle removal: Synergistic particle charging and filter polarizing

Efficient particle removal technology with minimal pressure drop is urgently needed for both air purification and energy conservation. We developed a compact electrostatically assisted air (cEAA) coarse filter, whose particle removal performance is enhanced by the synergistic effect of a corona charging field and a polarizing field. We investigated the influences of charging voltage (U), polarizing distance (dpl), effect of dielectric and geometric characteristics of the filter material on fraction filtration efficiency of PM0.01∼5, net ozone production, pressure drop and power dissipation of the cEAA coarse filter. Our experiments were performed in a ventilation duct using ambient air particulate matter. We found an optimal U between the corona charging onset voltage and the polarizing onset voltage that enhances particle filtration efficiency with nearly no net ozone production and low energy consumption. Single pass filtration efficiency for 0.3 μm particles increased from 4% to 69% with U varying from 0 to +9 kV (dpl = 3.5 cm). We found that filter material of larger relative dielectric constant or larger tortuosity yields higher filtration efficiencies. During a 458-h long-term operating period, the single pass filtration efficiency of the cEAA coarse filter did not decrease but increased slightly, and the pressure drop grew from 14.3 Pa to 31.5 Pa. We present a design strategy for a cEAA coarse filter with less than 30 Pa pressure drop at 1 m/s air velocity.

Endothelial factors in the pathogenesis and treatment of chronic kidney disease Part I: General mechanisms: a joint consensus statement from the European Society of Hypertension Working Group on Endothelin and Endothelial Factors and The Japanese Society of Hypertension.

: Kidney damage is a common consequence of arterial hypertension, but is also a cause of atherogenesis. Dysfunction and/or harm of the endothelium in glomeruli and tubular interstitium damage the function of these structures and translates into dynamic changes of filtration fraction, with progressive reduction in glomerular filtration rate, expansion of extracellular fluid volume, abnormal ion balance, and hypoxia, ultimately leading to chronic kidney disease. Considering the key role played by endothelial dysfunction in chronic kidney disease, the Working Group on Endothelin and Endothelial Factors of the European Society of Hypertension and the Japanese Society of Hypertension have critically reviewed available knowledge on the mechanisms underlying endothelial cell injury. This resulted into two articles: in the first, we herein examine the mechanisms by which endothelial factors induce vascular remodeling and the role of different players, including endothelin-1, the renin-angiotensin-aldosterone system and their interactions, and of oxidative stress; in the second, we discuss the role of endothelial dysfunction in the major disease conditions that affect the kidney.

El triacetato de celulosa asimétrico es una alternativa segura y eficaz para la hemodiafiltración en línea

BackgroundIn post-dilution haemodiafiltration only synthetic membranes have been used to date. Asymmetric cellulose triacetate (ATA™) is now available, whose characteristics are suitable for this technique. ObjectivesTo describe the in vivo performance and behaviour of this membrane, to identify its depurative effectiveness, use in clinical practice and its biocompatibility, both acute and after one month of treatment. MethodsObservational prospective study of 23 patients who were dialysed for 4 weeks using an ATA™ membrane and who maintained their prior regimen. ResultsA total of 287 sessions were performed and 264 complete sessions were collected. With an effective time of 243.7 (17.6) min and a mean blood flow of 371.7 (23) ml/min, an average Kt of 56.3 (5.3) l was observed, as well as a convection volume of 27.1 (4.2) l, a filtration fraction of 29.9 (3.7) %, a urea reduction ratio (RR) of 81 (5.2) %, a creatinine RR of 74.7 (4.6) %, a β2-microglobulin RR of 76.5 (4.8) % and a retinol binding protein RR of 18.6 (7.6) %. There were no technical problems or alarms. Changing the heparin dosage was not necessary. No increases in C3a or C5a concentrations or leukopenia were observed in the first 30min of the session. Neither the monocyte subpopulations nor IL-β1 or IL-6 were significantly altered after one month of treatment. ConclusionsThe new ATA™ membrane achieves adequate Kt and convection volume, without technical problems and with good biocompatibility and inflammatory profiles. It is therefore a valid option for post-dilution haemodiafiltration, particularly in patients allergic to synthetic membranes.

Adiposity Impacts Intrarenal Hemodynamic Function in Adults With Long-standing Type 1 Diabetes With and Without Diabetic Nephropathy: Results From the Canadian Study of Longevity in Type 1 Diabetes.

Central adiposity is considered to be an important cardiorenal risk factor in the general population and in type 1 diabetes. We sought to determine the relationship between central adiposity and intrarenal hemodynamic function in adults with long-standing type 1 diabetes with and without diabetic nephropathy (DN). Patients with type 1 diabetes (n = 66, duration ≥50 years) and age-/sex-matched control subjects (n = 73) were studied. The cohort was stratified into 44 DN Resistors (estimated glomerular filtration rate [eGFR] >60 mL/min/1.73 m2 and <30 mg/day urine albumin) and 22 patients with DN (eGFR ≤60 mL/min/1.73 m2 or ≥30 mg/day urine albumin). Intrarenal hemodynamic function (glomerular filtration rate for inulin [GFRINULIN], effective renal plasma flow for p-aminohippuric acid [ERPFPAH]) was measured. Afferent arteriolar resistance, efferent arteriolar resistance, renal blood flow, renal vascular resistance [RVR], filtration fraction, and glomerular pressure were derived from the Gomez equations. Fat and lean mass were quantified by DXA. Whereas measures of adiposity did not associate with GFRINULIN or ERPFPAH in healthy control subjects, trunk fat mass inversely correlated with GFRINULIN (r = -0.46, P < 0.0001) and ERPFPAH (r = -0.31, P = 0.01) and positively correlated with RVR (r = 0.53, P = 0.0003) in type 1 diabetes. In analyses stratified by DN status, greater central adiposity related to lower GFRINULIN values in DN and DN Resistors, but the relationships between central adiposity and ERPFPAH and RVR were attenuated and/or reversed in patients with DN compared with DN Resistors. The adiposity-intrarenal hemodynamic function relationship may be modified by the presence of type 1 diabetes and DN, requiring further study of the mechanisms by which adiposity influences renal hemodynamic function.

177Lu-DOTATATE Peptide Receptor Radionuclide Therapy in Patients with Borderline Low and Discordant Renal Parameters: Treatment Feasibility Assessment by Sequential Estimation of Triple Parameters and Filtration Fraction.

The aim was to assess the effect of standard fixed-dose protocol of 177Lu-DOTATATE peptide receptor radionuclide therapy (PRRT) in patients with borderline low renal function of one parameter (glomerular filtration rate [GFR], effective renal plasma flow [ERPF] or serum creatinine), that was discordant with the remaining parameters and determine the feasibility of this procedure in this group of patients. Renal toxicity of PRRT is a routine issue or concern for such cases. We compared different renal parameters used for pretherapy assessment in patients with borderline low single parameter at baseline and their potential significance with regards to deterioration of renal function subsequently. A retrospective analysis was performed in patients of metastatic neuroendocrine tumors who received therapeutic 177Lu-DOTATATE (using standard fixed-dose protocol) and had borderline compromised renal parameter values (either of GFR/ERPF/serum creatinine). Filtration fraction (FF) was also estimated in each case and all renal parameters were correlated using kappa statistics. The characteristics of cases showing progressive worsening of renal function in the follow-ups were also studied. A total of 15 patients (11 males, 4 females; age range: 32–75 years) were selected among a population of 450 patients. The follow-up duration ranged from 10 to 48 months and administered cumulative activity ranged 9.9–31.3 GBq (2–5 cycles). Based on the parameter characteristics, the study population was divided into following four groups: (a) patients with reduced GFR and maintained ERPF and normal serum creatinine (n = 3); (b) patients with reduced ERPF with maintained GFR and borderline elevated/normal serum creatinine (n = 3); (c) patients with both reduced GFR and ERPF and maintained serum creatinine (n = 1); (d) patients with compromised single kidney function (n = 5). A total of four patients were found who had normal baseline renal function values but showed progressive worsening in the subsequent period. There was no significant change in renal parameters during the follow-up in both Groups a and c. Two patients of Group b demonstrated well-maintained other renal parameters, whereas in 1 patient, there was the evidence of renal toxicity with gradual fall of GFR and ERPF and progressive increase in serum creatinine level. In patients with compromised single kidney function at baseline (Group d), there was overall maintained normal renal parameters, whereas 3 of 5 (60%) showed the increase of FF of the affected kidney. Interestingly, a compensatory hyperfunction was noted in the contralateral kidney. PRRT with 177Lu-DOTATATE is feasible and can be considered in patients with reduced GFR and with maintained ERPF and normal serum creatinine and also in the presence of single compromised parameter if the other two are normal; however, these patients need critical monitoring.

Hormonal therapy in women: Renal adverse effects

Chronic Kidney Disease (CKD) is commonly associated with menstrual disorders, infertility, and premature menopause. Nephrologists are often considered as the primary care providers by their patients, but perceptions of nephrologists on management of these issues are currently unknown. Studies proved there was a high level of uncertainty among Nephrologists with regard to the role of Hormonal Therapy (HT) in women with CKD. Primary ovarian function appears to be preserved in the setting of CKD, ovulatory and menstrual irregularities observed in the CKD are likely to be the consequence of hypothalamic and pituitary, rather than ovarian. Increases renal tubular responsiveness to changes in sodium intake leading to an increased GFR and filtration fraction, an increase in renal nitric oxide and an increase in Renin–Angiotensin Activity (RAS), which has been linked to a greater risk of diabetic nephropathy while hormonal replacement therapy was associated with a 19% reduction in ACR (P=0.008) and an odds ratio of 0.67 (95% confidence interval, 0.43 to 1.01; P=0.06).

Extraction and Serological Properties of Mycobacterium Cell Surface and Excreted Proteins

Modern medicine still faces the task of distinguishing active and latent tuberculosis cases at the early stage of the disease. Serological approaches have their advantages for their use in diagnostics. However, the progress of these approaches is ongoing but further progress is needed to meet the needs for this disease. Here, we extracted Mycobacterium tuberculosis H37Rv proteins from culture medium or from the cell surface and studied their reactivity with anti-M. tuberculosis serum in both ELISA and immunoblots. We found that M. tuberculosis surface proteins, extracted using dimethyl sulfoxide, with molecular weights in the range of 6.5–200 kDa, showed strong specific reactivity with anti-M. tuberculosis positive serum. While excreted proteins in the molecular weight range of 32–45 kDa had the highest reactivity. The latter was confirmed serologically when very weak signal was detected from the filtrate fractions compared to stronger activity from the Vivaspin 50 kDa MWCO retentates. Moreover, Mycobacterium bovis and tuberculosis proteins from the filter retentates had clear specific serum reactivity, which suggests that this approach can be used for differential diagnosis of two infections.

Relaxin-mediated renal vasodilation in the rat is associated with falls in glomerular blood pressure.

Relaxin (RLX) is a pleiotropic peptide hormone with marked renal vasodilatory actions that are physiologically important during pregnancy. RLX also has potent antifibrotic actions and is being tested therapeutically in various fibrotic diseases, including chronic kidney disease (CKD). Since renal vasodilation may expose the glomerulus to increased blood pressure [glomerular capillary pressure (PGC)], which exacerbates progression of CKD, we assessed the glomerular hemodynamic actions of acute (0.89 µg·100 g body wt-1·h-1 iv over 75 min) and chronic (1.5 µg·100 g body wt-1·h-1 sc) administration of RLX. Both acute and chronic RLX produced marked renal vasodilation and increased renal plasma flow (RPF) in euvolemic, anesthetized male rats. Glomerular filtration rate also increased with RLX, but the magnitude of the rise was much less than the increase in RPF due to concomitant decreases in filtration fraction. The fall in filtration fraction was the result of significant decreases in PGC, despite a slight increase in mean arterial blood pressure (MAP) with acute RLX and no net change in MAP with chronic RLX. This fall in PGC occurred because of the "in-series" arrangement of the afferent and efferent arteriolar resistance vessels, which can regulate PGC independently of MAP. With both acute and chronic RLX, efferent arteriolar resistance vessels relaxed to a greater extent than afferent arteriolar resistance vessels, thus producing falls in PGC. Based on this finding, RLX has a beneficial hemodynamic impact on the kidney, which, together with the antifibrotic actions of RLX, suggests a strong therapeutic potential for use in CKD.

Response of volume and osmoregulatory kidney function to infusion loading in patients with dopamine-dependent compensation of sepsis-induced hypotension

Objective . To study the response of volume and osmoregulatory kidney function to increased volume of extracellular space (IVECS) with dopamine-dependent compensation of sepsis-induced hypotension. Materials and methods. The inclusion criteria involved patients with purulent-septic complications (predominantly surgical abdominal sepsis) with dopamine-dependent compensation (5–10 μg/kg-min) according to the initial values: SBP >70 mmHg, BPs >95 mmHg, CVP >4 mmHg, diuresis >30 ml/h. The control group consisted of patients with systemic inflammatory response syndrome (SIRS) who met the requirements of ICD-10 classifier: SIRS, ICD-10: R-65.2. All patients were divided into 4 groups: groups I and II for control studies (SIRS, n = 21); groups III and IV included patients with severe sepsis (n = 30). The patients of groups II and IV received an infusion load in the form of Ringer's solution in the amount of 7–8 ml/kg at a rate of 18–20 ml/min. Results . The depression of glomerular filtration rate (GFR) in the patients from group ІІІ was 41 % (Р < 0.05), the excreted water fraction was 45 % higher than the control value (Р < 0.05), and urine output reached 88 % (Р < 0.05) of that in the comparison group. This result is due to different reabsorption rates. In doing so the sodium clearance was 81 % (P < 0.05) of the SIRS rate. The main cause is a decrease in the sodium filtration fraction, as the reabsorption of the cation according to the values of the excreted fraction was less than the control value. Depression of the osmoregulatory function of the kidneys had the same direction. The comparative analysis of the values between groups ІІ and IV (response of volume and osmoregulatory kidney function in patients with SIRS and severe sepsis (SS) to IVECS) shows that after IVECS the GFR remains reduced and represents 59 % of that in group II. Despite the more intensive compensatory suppression of water reabsorption, sodium and osmotically active substances (OAS) according to the indicators of the excreted fraction of water, sodium and OAS (an increase, Δ, P < 0.05) and a decrease in clearance of sodium-free water, in the reabsorption of osmotically free water (Δ, P < 0.05), in sodium clearance and OAS after IVECS in the patients from group IV were reduced by 16 % and 35 %, in urine output by 26 % (P < 0.05) respectively. Conclusions. In compensated sepsis-induced hypotension despite the compensatory suppression of water, sodium and OAS reabsorption according to the clearance characteristics there is an inhibition of volume and osmoregulatory kidney function both spontaneously (by 19 and 24 %, Δ, P < 0.05) and, accordingly, after IVECS (by 16 and 35 %, Δ, P < 0.05).

Potential of High-Affinity, Slow Off-Rate Modified Aptamer Reagents for Mycobacterium tuberculosis Proteins as Tools for Infection Models and Diagnostic Applications.

ABSTRACTDirect pathogen detection in blood to diagnose active tuberculosis (TB) has been difficult due to low levels of circulating antigens or due to the lack of specific, high-affinity binding reagents and reliable assays with adequate sensitivity. We sought to determine whether slow off-rate modified aptamer (SOMAmer) reagents with subnanomolar affinity for Mycobacterium tuberculosis proteins (antigens 85A, 85B, 85C, GroES, GroEL2, DnaK, CFP10, KAD, CFP2, RplL, and Tpx) could be useful to diagnose tuberculosis. When incorporated into the multiplexed, array-based proteomic SOMAscan assay, limits of detection reached the subpicomolar range in 40% serum. Binding to native M. tuberculosis proteins was confirmed by using M. tuberculosis culture filtrate proteins and fractions from infected macrophages and via affinity capture assays and subsequent mass spectrometry. Comparison of serum from culture-positive pulmonary TB patients and TB suspects systematically ruled out for TB revealed small but statistically significant (P < 0.0001) differences in the median M. tuberculosis signals and in specific pathogen markers, such as antigen 85B. Samples where many M. tuberculosis aptamers produced high signals were rare exceptions. In concentrated, protein-normalized urine from TB patients and non-TB controls, the CFP10 (EsxB) SOMAmer yielded the most significant differential signals (P < 0.0276), particularly in TB patients with HIV coinfection. In conclusion, direct M. tuberculosis antigen detection proved difficult even with a sensitive method such as SOMAscan, likely due to their very low, subpicomolar abundance. The observed differences between cases and controls had limited diagnostic utility in serum and urine, but further evaluation of M. tuberculosis SOMAmers using other platforms and sample types is warranted.

Hemofiltration induces generation of leukocyte-derived CD31+/CD41\u2212 microvesicles in sepsis

BackgroundMicrovesicles (MV) are extracellular vesicles known to be associated with cellular activation and inflammation. Hemofiltration is an effective blood purification technique for patients with renal failure and possibly also eliminates inflammatory mediators in the setting of sepsis. On the other hand, proinflammatory stimuli are induced by blood contacting the artificial membrane during extracorporeal blood purification. In chronic dialysis patients a systemic increase in MV has been described. The aim of the study was to investigate whether hemofilter passage of blood in continuous veno-venous hemofiltration (CVVH) alters MV composition and levels in critically ill patients with sepsis.MethodsPre- and postfilter bloods as well as ultrafiltrate samples from intensive care unit patients with severe sepsis were obtained during CVVH with regional citrate anticoagulation. MV subtypes in blood were analyzed by high-sensitivity flow cytometry. Additionally, tissue factor (TF) levels and MV-associated TF activities as well as MV activities were quantified. All parameters were corrected for hemoconcentration applied during CVVH.ResultsTwelve patients were analyzed. A significant increase in presumably mostly leukocyte-derived CD31+/CD41− MV (1.32 (1.09–1.93)-fold [median (25th–75th quartiles)], p = 0.021) was observed post- to prefilter, whereas platelet-derived MV as well as AnnexinV-binding MV were unaltered. Increments of AnnexinV+, CD42b+ and CD31+/CD41− MV post- to prefilter correlated with filtration fraction (FF) (all p < 0.05). Significant reductions in MV activity [0.72 (0.62–0.84)-fold, p = 0.002] and TF level [0.95 (0.87–0.99)-fold, p = 0.0093] were detected postfilter compared to prefilter. No MV activity was measurable in ultrafiltrate samples.ConclusionsDespite clearing a fraction of small PS-exposing MV CVVH does not eliminate larger MV. Concurrently, CVVH induces the release of CD31+/CD4− MV that indicate leukocyte activation during hemofilter passage in septic patients. Increments of several MV subtypes within the hemofilter correlate with FF, which supports common recommendations to keep FF low. A fraction of TF is being cleared by CVVH via ultrafiltration.

Abstract P139: Dual Angiotensin Receptor and Neprilysin Inhibition Improves Renal Hemodynamics and Reduces Kidney Damage in Diabetic Rats

Dual blockade with an Angiotensin Receptor/Neprilysin Inhibitor (ARNI) reduces proteinuria and glomerulosclerosis in diabetic TGR(mREN2)27 rats (i.e., rats displaying angiotensin II-dependent hypertension) more strongly than single AR blockade (ARB), despite a similar effect on blood pressure. Here we investigated whether this is due to improved renal hemodynamics and/or suppression of renal inflammation. TGR(mREN2)27 rats were made diabetic with streptozotocin for 12 weeks, and treated with placebo (n=10), valsartan (ARB; n=8) or valsartan/sacubitril (ARNI; n=8) from week 9-12. Blood pressure was measured by telemetry. Effective renal plasma flow (eRPF) and glomerular filtration rate (GFR) were assessed by quantifying para-aminohippuric acid and inulin clearances. Renal inflammation was quantified by qPCR (CD68 and CD3ε expression, representative for macrophages and T cells, respectively) and fluorescent activated cell sorting (FACS) analysis. ARNI and ARB lowered blood pressure identically, while only ARNI reduced albuminuria. Severe, chronic ischemia and globally sclerotic glomeruli occurred less frequently in kidneys of ARNI-treated animals vs. ARB-treated animals and controls. ARNI, but not ARB, increased eRPF, and a similar trend was observed for GFR. No treatment affected filtration fraction. ARNI decreased CD68 mRNA expression in both renal cortex and medulla, while ARB increased CD68 as well as CD3ε expression in renal medulla. FACS analysis revealed no differences between the treatment groups in the immune-cell fractions that had infiltrated the kidney. In conclusion, improved renal hemodynamics, combined with reduced macrophage infiltration, may underlie the stronger beneficial effects of ARNI on albuminuria and renal histology in diabetic TGR(mREN2)27 rats versus ARB.