Exacerbation of spontaneous autoimmune nephritis following regulatory T cell depletion in B cell lymphoma 2-interacting mediator knock-out mice.

Regulatory T cells (Tregs ) have been recognized as central mediators for maintaining peripheral tolerance and limiting autoimmune diseases. The loss of Tregs or their function has been associated with exacerbation of autoimmune disease. However, the temporary loss of Tregs in the chronic spontaneous disease model has not been investigated. In this study, we evaluated the role of Tregs in a novel chronic spontaneous glomerulonephritis model of B cell lymphoma 2-interacting mediator (Bim) knock-out mice by transient depleting Tregs . Bim is a pro-apoptotic member of the B cell lymphoma 2 (Bcl-2) family. Bim knock-out (Bim-/- ) mice fail to delete autoreactive T cells in thymus, leading to chronic spontaneous autoimmune kidney disease. We found that Treg depletion in Bim-/- mice exacerbated the kidney injury with increased proteinuria, impaired kidney function, weight loss and greater histological injury compared with wild-type mice. There was a significant increase in interstitial infiltrate of inflammatory cells, antibody deposition and tubular damage. Furthermore, the serum levels of cytokines interleukin (IL)-2, IL-4, IL-6, IL-10, IL-17α, interferon (IFN)-γ and tumour necrosis factor (TNF)-α were increased significantly after Treg depletion in Bim-/- mice. This study demonstrates that transient depletion of Tregs leads to enhanced self-reactive T effector cell function followed by exacerbation of kidney disease in the chronic spontaneous kidney disease model of Bim-deficient mice.

A better diet quality is associated with a reduced likelihood of CKD in older adults.

BACKGROUND AND AIMS: Studies of diet in relation to chronic kidney disease (CKD) have focused on individual nutrients. The relationship between overall patterns of food intake and renal function has not been well explored. We aimed to investigate the associations between diet quality with the prevalence, incidence and progression of CKD in a cohort of older adults. METHODS AND RESULTS: 1952 participants aged ≥50 years at baseline were examined between 1992-1994 and 2002-2004. Dietary data were collected using a semi-quantitative food frequency questionnaire. A modified version of the Healthy Eating Index for Australians was developed to determine total diet scores (TDS). Baseline biochemistry including serum creatinine was measured. CKD was defined as MDRD estimated glomerular filtration rate (eGFR) <60 mL min⁻¹·1.73 m⁻². Participants in the highest quartile of mean TDS compared to those in the first quartile (reference), had a 41% reduced likelihood of having eGFR <60 mL min⁻¹·1.73 m⁻², [multivariable-adjusted odds ratio, OR, 0.59 (95% confidence intervals, CI, 0.41-0.85), P-trend = 0.005]. Each unit increase in TDS was associated with a 15% decrease in the odds of having prevalent CKD, multivariable-adjusted OR 0.85 (95% CI 0.74-0.97). A non-significant, inverse association between TDS and CKD incidence was observed (P-trend = 0.10). CONCLUSION: Older adults with better diet quality had a reduced likelihood of having eGFR <60 mL min⁻¹·1.73 m⁻². Adherence to dietary guidelines were not prospectively associated with CKD incidence or progression. Further studies with adequate power are warranted to assess the longitudinal association between diet quality and CKD.

Macrophages and dendritic cells for treating kidney disease.

Based on new understanding of the diverse biological functions of macrophages and dendritic cells (DC), the focus of studies on these cells has been expanded from their pathogenic role in renal diseases to include their potential to regulate inflammation and restore renal architecture and function. By exploiting their regulatory function, macrophages or DC have been used to treat experimental renal disease following their adoptive transfer. This review summarizes current progress in the therapeutic use of macrophages and DC in renal diseases. Key issues for ongoing research are discussed.

Nuclear proteins. II. Similarity of nonhistone proteins in nuclear sap and chromatin, and essential absence of contractile proteins from mouse liver nuclei.

High resolution SDS slab gel electrophoresis has been used to examine the distribution of nonhistone proteins (NHP) in the saline-EDTA, Tris, and 0.35 M NaCl washes of isolated mouse liver nuclei. These studies led to the following conclusions: (a) all the prominent NHP which remain bound to DNA are also present in somewhat similar proportions in the saline-EDTA, Tris, and 0.35 M NaCl washes of nuclei; (b) a protein comigrating with actin is prominent in the first saline-EDTA wash of nuclei, but present as only a minor band in the subsequent washes and on washed chromatin; (c) the presence of nuclear matrix proteins in all the nuclear washes and cytosol indicates that these proteins are distributed throughout the cell; (d) a histone-binding protein (J2) analogous to the HMG1 protein of K. V. Shooter, G.H. Goodwin, and E.W. Johns (Eur J. Biochem. 47:236-270) is a prominent nucleoplasmic protein; (e) quantitation of the major NHP indicates that they are present in a range of 2.2 X 10(5)-5.2 X 10(6) copies per diploid nucleus. Most of the electrophoretically visible NHP are probably structural rather than regulatory proteins; (f) actin, myosin, tubulin, and tropomyosin, if present at all, constitute a very minor fraction of the nuclear NHP. Contractile proteins constitute a major portion of the NHP only when the chromatin is prepared from crude cell lysates instead of from purified nuclei. These studies support the conclusion that there are no clear differences between many nucleoplasmic and chromatin-bound nonhistone proteins. Except for the histones, many of the intranuclear proteins appear to be in equilibrium between DNA, HnRNA, and the nucleoplasm.

Functional equivalence of iron bound to human transferrin at low pH or high pH.

Human transferrin was labeled with 59Fe at one of its two metal-binding sites (designated A) at pH 6.0. 55Fe was then added to site B at pH 7.5. Both isotopes of iron were taken up in equal proportions by human reticulocytes. These experiments do not support the hypothesis that each binding site of transferrin has a different physiologic function.

Binding of xylenol orange to transferrin. Demonstration of metal-anion linkage.

The iron transport protein, transferrin, binds two metal ions and, concomitantly, two carboxylate anions. The metal ion indicators, xylenol orange and semi-xylenol orange are carboxylate anions which exhibit a characteristic visible spectrum when attached to a metal. We prepared the ternary complexes VO2+-transferrin-xylenol orange and VO2+-transferrin-semi-xylenol orange. The EPR spectra show that the vanadyl ion is attached to the protein and the visible spectra show that the xylenol orange or semi-xylenol orange is attached to the metal. The implication is that in other metal-transferrin-anion complexes, the anion is directly attached to the metal.

Model system oxidations supporting the crystal growth model of ferritin iron uptake.

Fe2+ is oxidized and taken up by ferritin or ápoferritin in the presence of dioxygen. Iodate causes Fe2+ oxidation and uptake by ferritin, but not by apoferritin. Synthetic iron polymer facilitates Fe2+ oxidation by either dioxygen or iodate. Nitrilotriacetic acid or iminodiacetic acid facilitate oxidation of Fe2+ by oxygen but not by iodate. These results support the crystal growth model of ferritin iron uptake, with iron polymer serving as a model for the ferritin core and aminocarboxylic acids mimicking the metal-binding sites of apoferritin.

Reduction potential of iron in transferrin.

The reduction potential of Fe3+ in transferrin was measured spectrophotometrically by equilibration with methyl viologen in the presence of sodium dithionite. For an ionic strength near 0.1 M at 25 degrees C and pH 7.3 under 0.048 atm. CO2, half of the iron is reduced at a potential near -0.40 V (vs. standard hydrogen electrode). At least one disulfide bond of the protein is partially reduced at a potential of -0.44 V, as evidenced by reaction with [14C]iodoacetate.

Retardation of kidney failure -- applying principles to practice.

Over the next decade, the number of patients with end-stage renal disease (ESRD) treated by dialysis may double, and even developed nations will have difficulty in coping with this alarming increase. This review will outline the proven and unproven strategies that have the potential to retard the progression of chronic kidney disease (CKD). Recently, a number of randomised clinical trials have demonstrated the efficacy of several strategies to slow the progression of CKD. Proven strategies include adequate blood pressure control (with angiotensin blockade), and for diabetic nephropathy good glycaemic control. Other potentially beneficial strategies include smoking cessation, lipid control and aldosterone blockade. The early institution of these strategies has the potential to regress established CKD as well as improve the long-term cardiovascular outcomes of these patients. Proof of the efficacy in humans of promising experimental approaches, such as the administration of growth factors (e.g., recombinant bone morphogenetic protein-7), anti-fibrotic agents (e.g., pirfenidone) and novel anti-proteinuric drugs (e.g., pentosan polysulphate), is awaited. Finally, the primary prevention of CKD, at least in part, by the eradication of type 2 diabetes and obesity (through improvement of lifestyle factors), and adequate treatment of hypertension, have the potential to eliminate up to half of the most common causes of CKD (or ESRD) in developed countries.

Proteinuria and tubulointerstitial injury.

These studies have demonstrated pathways whereby one urinary protein, holotransferrin, may alter proximal tubular cell function and cause tubular cytotoxicity, and at least two urinary proteins, albumin and transferrin, may mediate the development of interstitial inflammation in proteinuric renal disease.

Predictive value of 72-hour blastomere cell number on blastocyst development and success of subsequent transfer based on the degree of blastocyst development.

OBJECTIVE: To determine the predictive value of 72-hour blastomere cell number on blastocyst development and to compare success rates of subsequent transfer based on the degree of blastocyst development. DESIGN: Retrospective clinical study. SETTING: Private assisted reproductive technology center. PATIENT(S): Ninety-three women aged 32.0 +/- 5.1 years undergoing oocyte retrieval for IVF. INTERVENTION(S): Bipronucleate oocytes obtained from IVF were grown for up to 168 hours after fertilization and subsequently transferred at the blastocyst stage. MAIN OUTCOME MEASURE(S): Percentages of embryos developing to blastocyst from 72-hour embryos by blastomere cell number and subsequent implantation and pregnancy rates of transferred blastocysts. RESULT(S): Rates of blastocyst formation and expansion increased as cell numbers at 72 hours increased. Implantation rates were 43% for embryos transferred to women receiving only expanded blastocysts and 17% for embryos transferred to women receiving one or more less developed blastocysts. Pregnancy rates were higher for women receiving only expanded blastocysts than for women receiving one or more less developed blastocysts, although the difference was not significant. CONCLUSION(S): More developed 72-hour embryos are more likely to become blastocysts and expand. Implantation rates are greater for the transfer of expanded rather than unexpanded blastocysts.

A comparison of day 5 and day 6 blastocyst transfers.

OBJECTIVE: To compare implantation and pregnancy rates according to the day of embryo transfer (day 5 or 6 after oocyte retrieval) when transfer was postponed until expanded blastocysts developed. DESIGN: Retrospective clinical study. SETTING: Private ART center. PATIENT(S): One-hundred and eighty-three women undergoing blastocyst-stage embryo transfer following in vitro fertilization. INTERVENTION(S): Bipronucleate oocytes were grown for up to 144 hours and subsequently transferred only when at least one embryo attained the expanded blastocyst stage. MAIN OUTCOME MEASURE(S): Implantation and pregnancy rates. RESULT(S): Blastocysts transferred on day 5 implanted at nearly twice the rate of blastocysts transferred on day 6 (36.3% vs. 19.0%). Pregnancy rates were also almost twice as high among the day 5 transfer patients (59.3% vs. 32.3%). In addition, more blastocysts developed (3.6 vs. 2.4), and more were transferred (2.7 vs. 2.3) to the day 5 transfer patients, although the proportion of expanded blastocysts among the blastocysts that were transferred was the same for the two groups (91.7% vs. 93.6%). CONCLUSION(S): Embryos that develop to the expanded blastocyst stage and are transferred on day 5 after retrieval are approximately twice as likely to implant compared to those for which expansion and transfer are delayed until day 6.

Quantitative grading of a human blastocyst: optimal inner cell mass size and shape.

OBJECTIVE: To investigate the predictive value of quantitative measurements of blastocyst morphology on subsequent implantation rates after transfer. DESIGN: Prospective observational study. SETTING: Private assisted reproductive technology center. PATIENT(S): One hundred seventy-four IVF patients receiving transfers of expanded blastocyst-stage embryos on day 5 (n = 112) or day 6 (n = 62) after oocyte retrieval. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Blastocyst diameter, number of trophectoderm cells, inner cell mass (ICM) size, ICM shape, and implantation and pregnancy rates. RESULT(S): Blastocyst diameter and trophectoderm cell numbers were unrelated to implantation rates. Day 5 expanded blastocysts with ICMs of >4,500 microm(2) implanted at a higher rate than did those with smaller ICMs (55% vs. 31%). Day 5 expanded blastocysts with slightly oval ICMs implanted at a higher rate (58%) compared with those with either rounder ICMs (7%) or more elongated ICMs (33%). Implantation rates were highest (71%) for embryos with both optimal ICM size and shape. Pregnancy rates were higher for day 5 transfers of optimally shaped ICMs compared with day 5 transfers of optimally sized ICMs. CONCLUSION(S): Quantitative measurements of the inner cell mass are highly indicative of blastocyst implantation potential. Blastocysts with relatively large and/or slightly oval ICMs are more likely to implant than other blastocysts.

Dramatic declines in implantation and pregnancy rates in patients who undergo repeated cycles of in vitro fertilization with blastocyst transfer after one or more failed attempts.

OBJECTIVE: To compare the outcome of second and third cycles of in vitro fertilization with blastocyst transfer to the outcome of first attempts at IVF with blastocyst transfer. DESIGN: Retrospective study. SETTING: Private ART center. PATIENT(S): Three hundred and four patients undergoing treatment with in vitro fertilization with blastocyst transfer, 87 of which underwent at least one cycle of re-treatment after failing to achieve pregnancy in their first cycle. INTERVENTION(S): Bipronucleate oocytes were grown for up to 144 hours and subsequently transferred when at least one embryo attained the expanded blastocyst stage. MAIN OUTCOME MEASURE(S): Pregnancy and implantation rates. RESULT(S): Pregnancy rates per retrieval were significantly higher for patients undergoing their first cycle of in vitro fertilization with blastocyst transfer (36%) compared to those undergoing their second (19%) or their third (9%) cycles of treatment. Implantation rates per embryo were also higher for first cycles of in vitro fertilization with blastocyst transfer (30%) compared to second (18%) or third cycles (8%). CONCLUSION(S): Pregnancy and implantation rates decline dramatically in repeated cycles of in vitro fertilization with blastocyst transfer following one or more unsuccessful cycles of in vitro fertilization with blastocyst transfer.

Low-dosage epoetin in maintenance haemodialysis: costs and quality-of-life improvement.

Decisions about epoetin (recombinant human erythropoetin) dosage and target haematocrit in dialysis patients have been determined largely by the high acquisition cost of epoetin, but are made with incomplete knowledge about which target haematocrit gives the optimum clinical benefit. Haematopoietic response to epoetin may be determined by pharmacodynamic factors such as rate and frequency of administration, as well as by individual patient characteristics such as ethnicity. Resistance to epoetin may be due to iron or vitamin deficiency, natural or exogenous inhibitors of erythropoiesis and bone marrow fibrosis. The high acquisition cost of epoetin must be considered along with a number of other factors that can influence the true cost of epoetin treatment. Hidden costs of epoetin treatment include administration costs, changes in other treatments, extra laboratory tests and adverse events. Administration costs and extra laboratory surveillance add little to overall cost. Depletion of iron stores, hypertension, increased blood coagulability and reduced dialyser efficiency resulting from epoetin treatment may all add a small additional component to the true cost. Severe complications with significant cost implications are rare. Amongst the various components of true cost, only the acquisition cost can definitely be reduced by low dosage treatment. Balanced against the true and potential costs of epoetin are a number of benefits which can result in potential savings. The need for blood transfusion is all but abolished, avoiding the cost of transfusion and its complications. Sensitisation against histocompatibility antigens is reduced by avoiding transfusion, and so the waiting time for cadaveric transplantation may be reduced. Rates of hospitalisation for all causes, especially those associated with anaemia, may be reduced by epoetin treatment. By improving well-being, epoetin may allow patients to be transferred to minimal-care units or home where dialysis can be performed much more cheaply. Amongst the various potential benefits of epoetin, the one with the greatest potential to save money for society is improved productivity. To date, productivity improvements with epoetin have been demonstrated only in small studies. If the acquisition costs of epoetin are reduced by low dosage therapy, these potential benefits can cover a large proportion of the total cost of epoetin. Epoetin undoubtedly improves quality of life and activity, but it is not clear which level of haematocrit gives optimum improvement.(ABSTRACT TRUNCATED AT 400 WORDS)

A review of quality of life in chronic renal failure.

The quality of life of patients with end-stage renal disease (ESRD) has become an area of intensive investigation because of the high costs of renal-replacement therapy (dialysis or renal transplantation) and the rising prevalence of renal failure. Studies comparing quality of life of patients using different forms of renal-replacement therapy are flawed by deficiencies in study design, such as lack of randomisation. Nevertheless, in both retrospective and prospective studies, transplantation has been shown to offer the highest levels of functional ability, employment and subjective quality of life. After case-mix adjustment, there is little difference between peritoneal dialysis and haemodialysis in terms of quality-of-life (QOL) outcomes. Vocational rehabilitation is an important aim of therapy; for patients below retirement age, pre-dialysis education and counselling are important in maintaining employment. The elderly comprise the fastest-growing group of dialysis recipients; multiple comorbidities add to functional impairment in these patients. Subjective quality of life remains surprisingly high in many elderly patients, despite poor objective quality of life. The quality of life of patients with diabetes mellitus and ESRD is lower than that of nondiabetic patients with ESRD. For selected patients with insulin-dependent diabetes mellitus, combined renal and pancreatic transplantation offers the advantage of freedom from insulin injections. Unfortunately, available evidence suggests only small improvements in quality of life with combined transplantation versus kidney-only transplantation, probably because many patients have developed multiple diabetic complications by the time of transplantation. Epoetin alfa (erythropoietin) has been shown to improve quality of life in a number of trials. The optimal target haematocrit is a subject of controversy, but on current evidence, a target of 34 to 37% is reasonable. The degree of improvement in quality of life must be balanced against the additional costs of achieving a higher haematocrit. Further study is necessary to clarify the optimal target haematocrit for epoetin alfa therapy, as well as the possible effects of nutritional support, growth hormone in paediatric patients, and combined renal and pancreatic transplantation in improving quality of life.

Comparison of intermittent oral and intravenous calcitriol in hemodialysis patients with secondary hyperparathyroidism.

Both intermittent intravenous and intermittent oral calcitriol have been shown to be effective in the treatment of secondary hyperparathyroidism in hemodialysis patients and it has been claimed that intravenous calcitriol causes less hypercalcemia. However, there has been no published systematic comparison of the two routes of administration of intermittent calcitriol. Therefore in a prospective crossover study 11 (9 male) patients on maintenance hemodialysis were randomized to receive intravenous followed by oral calcitriol for 4 months each, or oral followed by intravenous calcitriol, commencing at 2 micrograms postdialysis three times per week. Initial serum immunoreactive parathyroid hormone (PTH) was 446 +/- 111 (normal < 65) pg/ml. Calcium-containing phosphate binders were not used. Calcitriol was ceased if hypercalcemia developed and restarted at 2 micrograms or 1 microgram when calcium returned to normal. Hypercalcemia was frequent (11 episodes in 8 patients on intravenous calcitriol and 10 episodes in 7 patients on oral calcitriol) and dose reduction to 1 microgram was necessary in 7 patients on intravenous and on 6 patients on oral. Serum PTH fell during both treatments. Parathyroid enlargement was seen in 10 glands from 4 patients, but no size reduction was demonstrated with treatment. There was no reduction in activity on quantitative metabolic bone scan. In summary, intermittent oral calcitriol and intermittent intravenous calcitriol were equally effective in reducing serum parathyroid hormone levels and at a dose of 2 micrograms postdialysis caused hypercalcemia with equal frequency.

Interpatient variation in response to subcutaneous versus intravenous low dose erythropoietin.

Subcutaneous (SC) recombinant human erythropoietin (EPO) has been reported to correct anemia in hemodialysis patients at lower doses than intravenous (IV) EPO. Those trials involved relatively high doses of EPO or did not control adequately for time-related falls in dose requirements. Therefore, on open-label double-crossover study was performed to compare the hemoglobin (Hb) response to low dose SC versus IV EPO. Ten (4 male) maintenance hemodialysis patients previously stabilised on low dose EPO for 18 +/- 3 months (mean +/- SEM) were given EPO IV for 12 weeks (IV#1), then SC for 24 weeks and then IV for a further 20 weeks (IV#2). Iron status and other factors known to modify response to EPO were kept constant. EPO dose was not changed unless Hb rose above 100 g/l, when the dose was reduced to keep Hb between 90 and 100 g/l. Initial EPO dose was 64 +/- 10 u/kg/week. Mean Hb, measured monthly, was not different during the 3 treatment periods. There was wide interpatient variation in the relative response to IV versus SC EPO. Mean Hb was higher on IV EPO in 5 patients (by 6.1 +/- 2.0 g/l) and higher on SC EPO in 5 patients (by 12.1 +/- 4.1 g/l). The difference in mean Hb during IV versus SC administration was more than 5 g/l in 6 patients, being higher in 3 patients during IV administration (by 8.7 +/- 4.6 g/l) and in 3 during SC (by 17.4 +/- 4.6 g/l). In conclusion, the more efficient route of administration of EPO is not predictable for individual patients, and should be sought to allow possible dose reduction.

Modeling Infection of Strawberry Flowers by Botrytis cinerea Using Field Data.

ABSTRACT The incidence of strawberry flower infection by Botrytis cinerea was monitored in unsprayed field plots in three successive years together with meteorological data and numbers of conidia in the air. There were large differences in conidia numbers and weather conditions in the 3 years. Three sets of models were derived to relate inoculum and weather conditions to the incidence of flower infection; by inoculum only, by weather variables only, and by both inoculum and weather variables. All the models fitted the observed incidence satisfactorily. High inoculum led to more infection. Models using weather variables only gave more accurate predictions than models using inoculum only. Models using both weather variables and inoculum gave the best predictions, but the improvement over the models based on weather variables only was small. The relationship between incidence of flower infection and inoculum and weather variables was generally consistent between years. Of the weather variables examined, daytime vapor pressure deficit and nighttime temperature had the greatest effect in determining daily incidence of flower infection. Infection was favored by low day vapor pressure deficit and high night temperature. The accuracy and consistency of the weather-based models suggest they could be explored to assist in management of gray mold.

Induction of proteinuric chronic glomerular disease in the rat (Rattus norvegicus) by intracardiac injection of doxorubicin hydrochloride.

Adriamycin nephropathy (AN) is a widely used nonimmune-mediated rat model of proteinuric chronic glomerular disease and is usually induced by a single intravenous injection of doxorubicin hydrochloride (DX) into the tail vein. However, this route can be associated with local skin necrosis and variability in disease induction and poses an occupational hazard to the investigator. Here we describe a simple technique of administering DX (1.7 mg) to ketamine:xylazine-sedated adult male Wistar rats (mean +/- 1 standard deviation, 238 +/- 8 g; n = 28) by using a single substernal intracardiac injection. The procedure was associated with minimal morbidity and mortality (1 death related to anesthesia). By day 21, severe nephrotic syndrome with effacement of glomerular epithelial cell foot processes and diffuse cortical tubulointerstitial injury was induced in all animals. Therefore, intracardiac injection of DX is a safe and consistent method of inducing AN in the rat and provides an alternative to the tail-vein route.