Diabetic nephropathy (DN), the leading cause of end-stage renal failure, is clinically manifested by albuminuria and a progressive decline in glomerular filtration rate. The risk factors and mechanisms that contribute to the development and progression of DN are still incompletely defined. To address the involvement of bradykinin B2-receptors (B2R) in DN, we used a genome wide approach to study the effects of diabetes on differential renal gene expression profile in wild type and B2R knockout (B2R−/−) mice. Diabetes was induced with streptozotocin and plasma glucose levels and albumin excretion rate (AER) were measured at predetermined times throughout the 23 week study period. Longitudinal analysis of AER indicated that diabetic B2R−/−D null mice had a significantly decreased AER levels compared to wild type B2R+/+D mice (P = 0.0005). Results from the global microarray study comparing gene expression profiles among four groups of mice respectively: (B2R+/+C, B2R+/+D, B2R−/−C and B2R−/−D) highlighted the role of several altered pathological pathways in response to disruption of B2R and to the diabetic state that included: endothelial injury, oxidative stress, insulin and lipid metabolism and inflammatory process with a marked alteration in the pro-apoptotic genes. The findings of the present study provide a global genomics view of biomarkers that highlight the mechanisms and putative pathways involved in DN.

In mammalian pregnancy, maternal cardiovascular adaptations must match the requirements of the growing fetus(es), and respond to physiologic and pathologic conditions. Such adaptations are particularly demanding for mammals bearing large-litter pregnancies, with their inherent conflict between the interests of each individual fetus and the welfare of the entire progeny. The mouse is the most common animal model used to study development and genetics, as well as pregnancy-related diseases. Previous studies suggested that in mice, maternal blood flow to the placentas occurs via a single arterial uterine loop generated by arterial-arterial anastomosis of the uterine artery to the uterine branch of the ovarian artery, resulting in counter bi-directional blood flow. However, we provide here experimental evidence that each placenta is actually supplied by two distinct arterial inputs stemming from the uterine artery and from the uterine branch of the ovarian artery, with position-dependent contribution of flow from each source. Moreover, we report significant positional- and inter-fetal dependent alteration of placental perfusion, which were detected by in vivo MRI and fluorescence imaging. Maternal blood flow to the placentas was dependent on litter size and was attenuated for placentas located centrally along the uterine horn. Distinctive apposing, inter-fetal hemodynamic effects of either reduced or elevated maternal blood flow, were measured for placenta of normal fetuses that are positioned adjacent to either pathological, or to hypovascular Akt1-deficient placentas, respectively. The results reported here underscore the critical importance of confounding local and systemic in utero effects on phenotype presentation, in general and in the setting of genetically modified mice. The unique robustness and plasticity of the uterine vasculature architecture, as reported in this study, can explain the ability to accommodate varying litter sizes, sustain large-litter pregnancies and overcome pathologic challenges. Remarkably, the dual arterial supply is evolutionary conserved in mammals bearing a single offspring, including primates.

Our objective was to test the hypothesis that aberrantly modified forms of superoxide dismutase (SOD1) influence the disease course for sporadic amyotrophic lateral sclerosis (SALS). We probed for anti-SOD1 antibodies (IgM and IgG) against both the normal and aberrantly oxidized-SOD1 (SODox) antigens in sera from patients with SALS, subjects diagnosed with other neurological disorders and healthy individuals, and correlated the levels of these antibodies to disease duration and/or severity. Anti-SOD1 antibodies were detected in all cohorts; however, a subset of ~5–10% of SALS cases exhibited elevated levels of anti-SOD1 antibodies. Those SALS cases with relatively high levels of IgM antibodies against SODox exhibit a longer survival of 6.4 years, compared to subjects lacking these antibodies. By contrast, SALS subjects expressing higher levels of IgG antibodies reactive for the normal WT-SOD1 antigen exhibit a shorter survival of 4.1 years. Anti-SOD1 antibody levels did not correlate with disease severity in either the Alzheimer’s or Parkinson’s disease cohorts. In conclusion, the association of longer survival with elevated levels of anti-SODox antibodies suggests that these antibodies may be protective. By extension, these data implicate aberrantly modified forms of WT-SOD1 (e.g. oxidized SOD1) in SALS pathogenesis. In contrast, an immune response against the normal WT-SOD1 appears to be disadvantageous in SALS, possibly because the anti-oxidizing activity of normal WT-SOD1 is beneficial to SALS individuals.

Introduction

Recent studies using mass spectrometry have discovered candidate biomarkers for amyotrophic lateral sclerosis (ALS). However these studies utilize small numbers of ALS and control subjects. Additional studies using larger subject cohorts are required to verify these candidate biomarkers.

Methods

Cerebrospinal fluid (CSF) from 100 patients with ALS, 100 disease control and 41 healthy control subjects were examined by mass spectrometry.

Results

61 mass spectral peaks exhibited altered levels between ALS and controls. Mass peaks for cystatin C and transthyretin were reduced in ALS, whereas mass peaks for post-translational modified transthyretin and C-reactive protein (CRP) were increased. CRP levels were 5.84±1.01 ng/mL for controls and 11.24±1.52 ng/mL for ALS subjects as determined by ELISA.

Discussion

This study verified prior mass spectrometry results for cystatin C and transthyretin in ALS. CRP levels were increased in the CSF of ALS patients, and cystatin C level correlated with survival in patients with limb-onset disease. Our biomarker panel predicted ALS with an overall accuracy of 82%.

Demographical factors such as race, vital status, gender and age could affect the final renal outcome of patients who undergo renal transplantation. These demographical factors could be assessed at a recipient and donor levels. Repeated measures for blood urea nitrogen (BUN) are typically recorded for each patient following renal transplantation, as a biomarker to assess renal progress. However, once a patient develops renal failure due to graft rejection, no measurement of BUN can be registered and the patient goes back to dialysis. This causes loss of follow-up and incomplete data on BUN measurements, a problem referred to as informative right censoring. If this problem is ignored inaccurate and biased estimates will be generated. In this study unbiased estimates for rate of change for BUN levels over time adjusted for informative right censoring and demographical factors were acquired using a sophisticated model of analysis. Our results demonstrated that BUN levels for Caucasians were decreasing at a greater rate than African-Americans (P<0.0001). When donors are deceased, African-American recipients showed an increase instead of a decrease in their BUN levels following transplantation. Moreover, African-Americans showed a decrease in their BUN levels when donors were African-Americans compared to when donors were Caucasians (P=0.03). Our results also showed that BUN levels were decreasing at a greater rate when donors and recipients were of different gender than when they were of same gender (P = 0.009). These results suggest that success of renal transplantation is impacted by donor/recipient demographical factors.

SUMMARY

Patients undergoing renal transplantation are prone to graft failure which causes lost of follow-up measures on their blood urea nitrogen and serum creatinine levels. These two outcomes are measured repeatedly over time to assess renal function following transplantation. Loss of follow-up on these bivariate measures results in informative right censoring, a common problem in longitudinal data that should be adjusted for so that valid estimates are obtained. In this study, we propose a bivariate model that jointly models these two longitudinal correlated outcomes and generates population and individual slopes adjusting for informative right censoring using a discrete survival approach. The proposed approach is applied to the clinical dataset of patients who had undergone renal transplantation. A simulation study validates the effectiveness of the approach.

OBJECTIVE—Because endothelial cell dysfunction and inflammation are key contributors to the development of complications in type 1 diabetes, we studied risk factors related to endothelial dysfunction and inflammation (C-reactive protein and fibrinogen, soluble vascular cell adhesion molecule-1, intracellular adhesion molecule-1, and E-selectin, and fibrinolytic markers) in a subgroup of patients from the Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Intervention and Complications (EDIC) study cohort.

RESEARCH DESIGN AND METHODS—We determined which of these risk factors or clusters thereof are associated with the presence of and subsequent development of nephropathy and macrovascular complications (reflected by carotid intima-media thickness [IMT]).

RESULTS—After adjustment for conventional risk factors (age, sex, DCCT treatment group, diabetes duration, A1C, systolic blood pressure, waist-to-hip ratio, total and HDL cholesterol, and smoking status), fibrinogen remained strongly associated with progression of internal and common carotid IMT (P < 0.01) and soluble E-selectin had a strong association with nephropathy (P < 0.01).

CONCLUSIONS—The best predictor for IMT progression in the DCCT/EDIC cohort was plasma fibrinogen, and the levels of soluble E-selectin discriminate patients with albuminuria better than conventional risk factors.

Urinary kallikrein excretion (UKE) is decreased in rats with passive Heymann nephritis (PHN), but increases after converting enzyme inhibition (CEI). Although CEI potentiates bradykinin activity, neither the effect of CEI on kallikrein secretion nor the abnormal renal kallikrein metabolism in PHN has been examined previously. To determine the mechanism by which CEI increases UKE, normal rats and PHN received enalapril, 40 mg/kg per d orally for 4 d. UKE was 85% lower in PHN than in normals and increased in both groups after CEI, although UKE in PHN remained significantly less than in normals. Kallikrein mRNA was significantly lower in PHN compared to normals but not in PHN treated with CEI and did not change in normal rats. Renin mRNA was significantly lower in PHN, and was stimulated by CEI only in normals. Renal kallikrein and renin content were not different and were not altered by CEI. Both kallikrein and renin genes appear to be transcriptionally suppressed in rats with PHN and the depressed kallikrein mRNA levels can be reversed by CEI. The modest increase in UKE despite normalization of kallikrein mRNA after CEI suggests that there is also a posttranscriptional defect in synthesis and/or secretion of kallikrein.

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This study examined the role of tissue kallikrein and kinins in renal vasodilation produced by infusion of amino acids (AA). In rats fed a 9% protein diet for 2 wk, intravenous infusion of a 10% AA solution over 60-90 min reduced total renal vascular resistance and increased glomerular filtration rate (GFR) by 25-40% and renal plasma flow (RPF) by 23-30% from baseline. This was associated with a two- to threefold increase in urinary kinin excretion rate. Acute treatment of rats with aprotinin, a kallikrein inhibitor, resulted in deposition of immunoreactive aprotinin in kallikrein-containing connecting tubule cells and inhibited renal kallikrein activity by 90%. A protinin pretreatment abolished the rise in urinary kinins and prevented significant increases in GFR and RPF in response to AA. In a second group of rats pretreated with a B2 kinin receptor antagonist, [DArg Hyp3, Thi5,8 D Phe7]bradykinin, AA infusion raised urinary kinins identically as in untreated controls, but GFR and RPF responses were absent. Aprotinin or the kinin antagonist produced no consistent change in renal function in rats that were not infused with AA.AA-induced increases in kinins were not associated with an increase in renal kallikrein activity. Notably, tissue active kallikrein level fell 50% in AA-infused rats. These studies provide evidence that kinins generated in the kidney participate in mediating renal vasodilation during acute infusion of AA.

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A mother and daughter were the sole survivors of a house fire. Support, maintenance of the parent-child relationship, and monitoring and facilitating the grieving process in a way that was consistent with the developmental stages of the patients were the basis of management.

The effects of streptozotocin (STZ) diabetes and insulin on regulation of renal kallikrein were studied in the rat. 1 and 2 wk after STZ injection, diabetic rats had reduced renal levels and urinary excretion of active kallikrein. Tissue and urinary prokallikrein levels were unchanged, but the rate of renal prokallikrein synthesis relative to total protein synthesis was reduced 30-45% in diabetic rats. Treatment of diabetic rats with insulin prevented or reversed the fall in tissue level and excretion rate of active kallikrein and normalized prokallikrein synthesis rate. To further examine insulin's effects, nondiabetic rats were treated with escalating insulin doses to produce hyperinsulinemia. In these rats, renal active kallikrein increased. Although renal prokallikrein was not increased significantly by hyperinsulinemia, its synthesis was increased. As this was accompanied by proportionally increased total protein synthesis, relative kallikrein synthesis rate was not changed. Excretion of active kallikrein was unchanged, but prokallikrein excretion was markedly reduced. Therefore, increased tissue active kallikrein seen with hyperinsulinemia can be explained not only by increased synthesis but also by retention and increased activation of renal prokallikrein. These studies show that STZ diabetes produces an impairment in renal kallikrein synthesis and suggest that this disease state also impairs renal prokallikrein activation. The findings also suggest that insulin modulates renal kallikrein production, activation, and excretion.

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