To develop antibody probes for the neutral side chains of pectins, antisera were generated to a pectic galactan isolated from tomato (Lycopersicon esculentum) pericarp cell walls and to a (1[>>]4)-[beta]-galactotetraose-bovine serum albumin neoglycoprotein. The use of these two antisera in immunochemical assays and immunolocalization studies indicated that they had very similar specificities. A monoclonal antibody (LM5) was isolated and characterized subsequent to immunization with the neoglycoprotein. Hapten inhibition studies revealed that the antibody specifically recognized more than three contiguous units of (1[>>]4)-[beta]-galactosyl residues. The antigalactan antibody was used to immunolocalize the galactan side chains of pectin in tomato fruit pericarp and tomato petiole cell walls. Although the LM5 epitope occurs in most cell walls of the tomato fruit, it was absent from both the locular gel and the epidermal and subepidermal cells. Furthermore, in contrast to other anti-pectin antibodies, LM5 did not label the cell wall thickenings of tomato petiole collenchyma.

Hypoalbuminemia predicts death in dialysis patients. Although hypoalbuminemia has been attributed to malnutrition, evidence of inflammation (C-reactive protein [CRP] and cytokine levels) has recently been recognized to predict albumin concentration in dialysis patients. We measured CRP and albumin levels in October 1995 in 91 hemodialysis (HD) patients. During a 34-month follow-up period, we determined the incidence and cause of death. Patients were divided into four groups based on serum albumin levels (<3.5 [lowest quartile], 3.5 to 3.8, 3.9 to 4.0, and >4.0 g/dL [highest quartile]). Survival differed among the four groups (P = 0.0063). Patients with albumin levels greater than 4.0 g/dL had the greatest survival. Kaplan-Meier survival estimates of patients from varying CRP quartiles (<2.6, 2.6 to 5.2, 5.3 to 11.5, and >11.5 microg/mL) differed among the four groups (P < 0.0001). The group with the greatest CRP level (>11.5 microg/mL) had the lowest survival. Multivariate analysis using the Cox proportional hazards model showed that only CRP level (chi-square = 21.11; P < 0.0001) and age (chi-square = 5.44; P = 0.020) predicted death. Albumin level (chi-square = 0.16; P = 0.69) was not predictive. Only when CRP was excluded from the model did low serum albumin level (chi-square = 12. 04; P = 0.0004) predict death. CRP level (chi-square = 16.79; P < 0. 0001) and age (chi-square = 6.38; P = 0.012) also superceded albumin level (chi-square = 0.45; P = 0.51) in predicting cardiovascular mortality. Although values for blood urea nitrogen, creatinine, and normalized protein catabolic rate were significantly less among patients who died, these parameters, as well as cholesterol level and diabetes, were not important predictors of death in multivariate analysis. The acute-phase response or the cause of the acute-phase response is largely responsible for the effect of hypoalbuminemia on mortality in HD patients.

A series of very potent derivatives of the 30-amino acid peptide hormone glucagon-like peptide-1 (GLP-1) is described. The compounds were all derivatized with fatty acids in order to protract their action by facilitating binding to serum albumin. GLP-1 had a potency (EC(50)) of 55 pM for the cloned human GLP-1 receptor. Many of the compounds had similar or even higher potencies, despite quite large substituents. All compounds derivatized with fatty acids equal to or longer than 12 carbon atoms were very protracted compared to GLP-1 and thus seem suitable for once daily administration to type 2 diabetic patients. A structure-activity relationship was obtained. GLP-1 could be derivatized with linear fatty acids up to the length of 16 carbon atoms, sometimes longer, almost anywhere in the C-terminal part without considerable loss of potency. Derivatization with two fatty acid substituents led to a considerable loss of potency. A structure-activity relationship on derivatization of specific amino acids generally was obtained. It was found that the longer the fatty acid, the more potency was lost. Simultaneous modification of the N-terminus (in order to obtain better metabolic stability) interfered with fatty acid derivatization and led to loss of potency.

BACKGROUND

Heavy proteinuria and progressive renal injury recur after transplantation in up to 40 percent of patients with renal failure caused by idiopathic focal segmental glomerulosclerosis. A circulating factor may be responsible for this recurrence.

METHODS

To determine whether patients with focal segmental glomerulosclerosis have a circulating factor capable of causing glomerular injury, we tested serum samples from 100 patients with the disorder in an in vitro assay of glomerular permeability to albumin. Of the 56 patients who had undergone renal transplantation, 33 had recurrences. Sixty-four patients, many of whom had undergone transplantation, were being treated with dialysis. Thirty-one patients with other renal diseases and nine normal subjects were also studied.

RESULTS

The 33 patients with recurrent focal segmental glomerulosclerosis after transplantation had a higher mean (+/-SE) value for permeability to albumin (0.47+/-0.06) than the normal subjects (0.06+/-0.07) or the patients who did not have recurrences (0.14+/-0.06). After plasmapheresis in six patients with recurrences, the permeability was reduced (from 0.79+/-0.06 to 0.10+/-0.05, P = 0.008), and proteinuria was significantly decreased. Patients with corticosteroid-sensitive nephrotic syndrome or with membranous nephropathy after transplantation had low levels of serum activity. The circulating factor bound to protein A and hydrophobic-interaction columns and had an apparent molecular mass of about 50 kd.

CONCLUSIONS

A circulating factor found in some patients with focal segmental glomerulosclerosis is associated with recurrent disease after renal transplantation and may be responsible for initiating the renal injury.

Previous in vitro findings suggest a critical role for the polymorphonuclear leukocyte (PMN) membrane glycoprotein complex CD18 in PMN adherence and chemotaxis. We examined the effect of the murine monoclonal antibody (MoAb) 60.3, recognizing CD18, on induced PMN accumulation in vivo. Rabbits were pretreated with MoAb 60.3, and the chemotactic factors fMLP, leukotriene (LT)B4, and C5a, as well as histamine, were injected intradermally; 4 hours later, plasma leakage (125I-albumin) and the PMN accumulation (myeloperoxidase) were determined. Both PMN accumulation and PMN-dependent plasma leakage were abolished in the inflammatory skin lesions of rabbits pretreated with MoAb 60.3 as compared with control animals, whereas histamine-induced PMN-independent plasma leakage was unaffected. Intravital microscopy of the rabbit tenuissimus muscle revealed that MoAb 60.3 inhibited both PMN adherence in the venules and migration into the tissue following application of LTB4 and zymosan-activated serum (ZAS). Rolling of PMNs along the venular endothelium was unaffected. Thus, these experiments confirm and extend earlier in vitro findings of the critical role of the membrane glycoprotein complex, CD18, in PMN adherence and chemotaxis.

OBJECTIVE

To determine long-term survival after pancreatoduodenectomy for pancreatic ductal adenocarcinoma and to identify clinical factors associated with long-term survival.

BACKGROUND

The prognosis for long-term survival even after potentially curative resection for pancreatic adenocarcinoma is thought to be poor. Clinical factors determining short-term survival after pancreatic resection are well studied, but prognostic factors predicting long-term survival with a potential for cure are poorly understood.

METHODS

A case-control study was conducted of 357 patients who underwent pancreatoduodenectomy for pancreatic ductal adenocarcinoma between 1981 and 2001. Histologic specimens were reanalyzed to confirm diagnosis. Follow-up was at least 5 years or until death.

RESULTS

There was an improved survival throughout the observation period (P = 0.004). We found 62 actual 5-year survivors of whom 21 patients survived greater than 10 years, for a 5- and 10-year survival rate of 18% and 13%, respectively. Cohort analysis comparing patients with short-term (<5 years, n = 295) and long-term >> or =5 years, n = 62) survival showed that more advanced disease (greatest tumor diameter, lymph node metastasis) and decreased serum albumin concentration were unfavorable for long-term survival (all P < 0.05). In contrast, the extent of resection and more aggressive histologic features did not correlate with long-term survival (all P>> 0.05). En-bloc resection (P = 0.005) but not resection margin status (P>> 0.05) was associated with long-term survival. Adjuvant chemoradiation therapy did not significantly influence long-term survival. Multivariate analysis identified lymph node status (OR 0.36, 95% CI 0.14-0.89, P = 0.03) as a prognostic factor for long-term survival. Five-year survival was no guarantee of cure because 16% of this subset died of pancreatic cancer up to 7.8 years after operation.

CONCLUSIONS

Pancreatoduodenectomy for adenocarcinoma in the head of pancreas can provide long-term survival in a subset of patients, particularly in the absence of lymph node metastasis. One of 8 patients can achieve 10-year survival with a potential for cure.

A quantitative Abelson murine leukemia virus (A-MuLV) lymphoid cell transformation assay has been developed using a semisolid agarose culture system. Under these conditions lymphoid cell transformation was shown to vary linearly with the dose of A-MuLV used. The susceptibility of bone marrow cells from different strains of mice to A-MuLV-induced transformation can be estimated using the agarose assay. Strains with bone marrow cells of high, medium, and low susceptibility to A-MuLV can be identified. The assay has been used to study the susceptibility of cells from lymphoid organs of fetal and adult mice to A-MuLV. Cell suspensions from fetal liver, adult bone marrow, and adult spleen are susceptible to A-MuLV, while thymocytes are resistant to A-MuLV-induced transformation. Bovine serum albumin gradient fractionation of bone marrow cells before infection with A-MuLV demonstrates that the majority of A-MuLV-sensitive cells are recovered in a broad band partially overlapping the majority of the nucleated cells. The agarose assay system allows study of A-MuLV-lymphoid cell interaction at the level of single cell-single virus particle interaction.

Human serum albumin (HSA), the most prominent protein in plasma, binds different classes of ligands at multiple sites. HSA provides a depot for many compounds, affects pharmacokinetics of many drugs, holds some ligands in a strained orientation providing their metabolic modification, renders potential toxins harmless transporting them to disposal sites, accounts for most of the antioxidant capacity of human serum, and acts as a NO-carrier. The globular domain structural organization of monomeric HSA is at the root of its allosteric properties which are reminiscent of those of multimeric proteins. Here, structural, functional, biotechnological, and biomedical aspects of ligand binding to HSA are summarized.

BACKGROUND

Patients with chronic kidney disease (stage 5) who undergo hemodialysis treatment have similarities to heart failure patients in that both populations retain fluid frequently and have excessively high mortality. Volume overload in heart failure is associated with worse outcomes. We hypothesized that in hemodialysis patients, greater interdialytic fluid gain is associated with poor all-cause and cardiovascular survival.

RESULTS

We examined 2-year (July 2001 to June 2003) mortality in 34,107 hemodialysis patients across the United States who had an average weight gain of at least 0.5 kg above their end-dialysis dry weight by the time the subsequent hemodialysis treatment started. The 3-month averaged interdialytic weight gain was divided into 8 categories of 0.5-kg increments (up to>> or =4.0 kg). Eighty-six percent of patients gained >1.5 kg between 2 dialysis sessions. In unadjusted analyses, higher weight gain was associated with better nutritional status (higher protein intake, serum albumin, and body mass index) and tended to be linked to greater survival. However, after multivariate adjustment for demographics (case mix) and surrogates of malnutrition-inflammation complex, higher weight-gain increments were associated with increased risk of all-cause and cardiovascular death. The hazard ratios (95% confidence intervals) of cardiovascular death for weight gain <1.0 kg and>> or =4.0 kg (compared with 1.5 to 2.0 kg as the reference) were 0.67 (0.58 to 0.76) and 1.25 (1.12 to 1.39), respectively.

CONCLUSIONS

In hemodialysis patients, greater fluid retention between 2 subsequent hemodialysis treatment sessions is associated with higher risk of all-cause and cardiovascular death. The mechanisms by which fluid retention influences cardiovascular survival in hemodialysis may be similar to those in patients with heart failure and warrant further research.

A large body of evidence now exists to substantiate that the endocannabinoid, anandamide, activates TRPV1 receptors. It is a low intrinsic efficacy TRPV1 agonist that behaves as a partial agonist in tissues with a low receptor reserve, while in tissues with high receptor reserve and in circumstances associated with certain disease states, it behaves as a full agonist. The efficacy of anandamide as a TRPV1 agonist is influenced by a succession of factors including receptor reserve, phosphorylation, metabolism and uptake, CB1 receptor activation, voltage, temperature, pH and bovine serum albumin. There are indications that the endocannabinoid system may play a role in the modulation of TRPV1 receptor activation. The activation of TRPV1 receptors by anandamide has potential implications in the treatment of inflammatory, respiratory and cardiovascular disorders. The relative importance of anandamide as a physiological and/or pathophysiological TRPV1 receptor agonist in comparison to other potential candidates has yet to be revealed.

OBJECTIVE

Sarcopenia, defined as a low level of muscle mass, occurs in patients with cirrhosis. We assessed its incidence among cirrhotic patients undergoing evaluation for liver transplantation to investigate associations between sarcopenia and mortality and prognosis.

METHODS

We studied 112 patients with cirrhosis (78 men; mean age, 54 ± 1 years) who were consecutively evaluated for liver transplantation and had a computed tomography scan at the level of the third lumbar (L3) vertebrae to determine the L3 skeletal muscle index; sarcopenia was defined by using previously published, sex-specific cutoffs.

RESULTS

Of the patients studied, 45 (40%) had sarcopenia. Univariate Cox analysis associated mortality with ascites (hazard ratio [HR], 2.12; P = .04), encephalopathy (HR, 1.99; P = .04), level of bilirubin (HR, 1.007; P < .01), international normalized ratio (HR, 7.69; P < .001), level of creatinine (HR, 1.01; P = .005), level of albumin (HR, 94; P = .008), serum level of sodium (HR, 89; P < .001), Model for End-Stage Liver Disease (MELD) score (HR, 1.14; P < .01), Child-Pugh score (HR, 2.84; P < .001), and sarcopenia (HR, 2.18; P = .006). By multivariate Cox analysis, only Child-Pugh (HR, 1.85; P = .04) and MELD scores (HR, 1.08; P = .001) and sarcopenia (HR, 2.21; P = .008) were independently associated with mortality. The median survival time for patients with sarcopenia was 19 ± 6 months, compared with 34 ± 11 months among nonsarcopenia patients (P = .005). There was a low level of correlation between L3 skeletal muscle index and MELD (r = -0.07; P = .5) and Child-Pugh scores (r = -0.14; P = .1).

CONCLUSIONS

Sarcopenia is associated with mortality in patients with cirrhosis. It does not correlate with the degree of liver dysfunction evaluated by using conventional scoring systems. Scoring systems should include evaluation of sarcopenia to better assess mortality among patients with cirrhosis.

Gold nanorods of different aspect ratios are prepared using the growth-directing surfactant, cetyltrimethylammonium bromide (CTAB), which forms a bilayer on the gold nanorod surface. Toxicological assays of CTAB-capped nanorod solutions with human colon carcinoma cells (HT-29) reveal that the apparent cytotoxicity is caused by free CTAB in solution. Overcoating the nanorods with polymers substantially reduces cytotoxicity. The number of nanorods taken up per cell, for the different surface coatings, is quantitated by inductively coupled plasma mass spectrometry on washed cells; the number of nanorods per cell varies from 50 to 2300, depending on the surface chemistry. Serum proteins from the biological media, most likely bovine serum albumin, adsorb to gold nanorods, leading to all nanorod samples bearing the same effective charge, regardless of the initial nanorod surface charge. The results suggest that physiochemical surface properties of nanomaterials change substantially after coming into contact with biological media. Such changes should be taken into consideration when examining the biological properties or environmental impact of nanoparticles.

The highly ordered, isoporous substructure of the glomerular slit diaphragm was revealed in rat and mouse kidneys fixed by perfusion with tannic acid and glutaraldehyde. The slit diaphragm was similar in both animal species and appeared as a continuous junctional band, 300-450 A wide, consistently present within all slits formed by the epithelial foot processes. The diaphragm exhibited a zipper-like substructure with alternating, periodic cross bridges extending from the podocyte plasma membranes to a central filament which ran parallel to and equidistant from the cell membranes. The dimensions and spacing of the cross bridges defined a uniform population of rectangular pores approximately 40 by 140 A in cross section and 70 A in length. The total area of the pores was calculated to be about 2-3% of the total surface area of the glomerular capillaries. Physiological data indicate that the glomerular filter functions as if it were an isoporous membrane which excludes proteins larger than serum albumin. The similarity between the dimensions of the pores in the slit diaphragm and estimates for the size and shape of serum albumin supports the conclusion from tracer experiments that the slit diaphragm may serve as the principal filtration barrier to plasma proteins in the kidney.

BACKGROUND

A selective combination of C-reactive protein and albumin (termed the modified Glasgow Prognostic Score, mGPS) has been shown to have prognostic value, independent of tumour stage, in lung, gastrointestinal and renal cancers. It is also of interest that liver function tests such as bilirubin, alkaline phosphatase and γ-glutamyl transferase, as well as serum calcium, have also been reported to predict cancer survival. The aim of the present study was to examine the relationship between an inflammation-based prognostic score (mGPS), biochemical parameters, tumour site and survival in a large cohort of patients with cancer.

METHODS

Patients (n=21,669) who had an incidental blood sample taken between 2000 and 2006 for C-reactive protein, albumin and calcium (and liver function tests where available) and a diagnosis of cancer were identified. Of this group 9608 patients who had an ongoing malignant process were studied (sampled within 2 years before diagnosis). Also a subgroup of 5397 sampled at the time of diagnosis (sampled within 2 months prior to diagnosis) were examined. Cancers were grouped by tumour site in accordance with International Classification of Diseases 10 (ICD 10).

RESULTS

On follow up, there were 6005 (63%) deaths of which 5122 (53%) were cancer deaths. The median time from blood sampling to diagnosis was 1.4 months. Increasing age, male gender and increasing deprivation was associated with a reduced 5-year overall and cancer-specific survival (all P<0.001). An elevated mGPS, adjusted calcium, bilirubin, alkaline phosphatase, aspartate transaminase, alanine transaminase and γ-glutamyl transferase were associated with a reduced 5-year overall and cancer-specific survival (independent of age, sex and deprivation in all patients sampled), as well as within the time of diagnosis subgroup (all P<0.001). An increasing mGPS was predictive of a reduced cancer-specific survival in all cancers (all P<0.001).

CONCLUSIONS

The results of the present study indicate that the mGPS is a powerful prognostic factor when compared with other biochemical parameters and independent of tumour site in patients with cancer.

OBJECTIVE

The goal of this study was to independently validate the recent observations on the predictive role of red cell distribution width (RDW) for outcomes in chronic heart failure and to provide epidemiologic data on the biological correlates of RDW in heart failure (HF). Understanding the mechanism underlying this observation is unclear, largely hampered by the lack of epidemiologic studies demonstrating factors that are associated with anisocytosis in cardiovascular diseases.

METHODS

One hundred ninety-five patients (145 men, 50 women) with systolic HF were enrolled and followed up for a median of 14.5 months. Primary end points were all-cause mortality and hospital readmission due to worsening HF symptoms. A total of 19 clinical chemistry, hematology, and biochemical variables were considered for analysis together with clinical parameters in Cox proportional hazards and multiple regression models.

RESULTS

Red cell distribution width was found to be an N-terminal pro-brain natriuretic peptide independent predictor of all-cause mortality (adjusted HR 1.61 per 1 SD increase) in our study. Multiple correlations between biomarkers of ineffective erythropoiesis (serum iron, ferritin, and soluble transferrin receptor levels), inflammation and acute-phase reaction (interleukin-6, soluble tumor necrosis factor (TNF) receptor I and soluble TNF receptor II, C-reactive protein, and prealbumin concentrations), undernutrition (total cholesterol and albumin levels), and renal function were observed. In the multiple regression model, the strongest relationship for RDW was obtained with soluble transferrin receptor, soluble TNF receptor I, soluble TNF receptor II, and total cholesterol.

CONCLUSIONS

Here we validate the strong, independent prediction of morbidity and mortality in HF by RDW. The described correlations between RDW and inflammation, ineffective erythropoiesis, undernutrition, and impaired renal function may facilitate the understanding why this marker is associated with adverse outcomes in HF.

Current efforts in cardiac tissue engineering center around the use of scaffolds that deliver cells to the epicardial surface. In this study, we examined the effects of fibrin glue as an injectable scaffold and wall support in ischemic myocardium. The left coronary artery of rats was occluded for 17 min, followed by reperfusion. Echocardiography was performed 8 days after infarction. One to 2 days later, either 0.5% bovine serum albumin (BSA) in phosphate-buffered saline, fibrin glue alone, skeletal myoblasts alone, or skeletal myoblasts in fibrin glue were injected into the ischemic left ventricle. Echocardiography was again performed 5 weeks after injection. The animals were then sacrificed and the hearts were fresh frozen and sectioned for histology and immunohistochemistry. Both the fractional shortening (FS) and infarct wall thickness of the BSA group decreased significantly after 5 weeks (p = 0.0005 and 0.02, respectively). In contrast, both measurements for the fibrin glue group, cells group, and cells in fibrin glue group did not change significantly (FS: p = 0.18, 0.89, and 0.19, respectively; wall thickness: p = 0.40, 0.44, 0.43, respectively). Fibrin glue is capable of preserving infarct wall thickness and cardiac function after a myocardial infarction in rats and may be useful as a biomaterial scaffold for myocardial cell transplantation.

This paper describes an investigation of the use of poly(lactic/glycolic acid) polymers for long-term delivery of high molecular weight, water-soluble proteins. Poly(lactic/glycolic acid) (PLGA) microspheres, containing (fluorescein isothiocyanate)-labeled bovine serum albumin and (fluorescein isothiocyanate)-labeled horseradish peroxidase, were prepared by a modified solvent evaporation method using a double emulsion. The microspheres were spherical with diameters of 55-95 microns and encapsulated more than 90% of the protein. The preparation method was gentle and maintained enzyme activity and protein solubility. Stability studies showed that the encapsulation of an enzyme inside PLGA microspheres can protect them from activity loss. When not placed inside PLGA microspheres, (fluorescein isothiocyanate)-labeled horseradish peroxidase lost 80% of its activity in solution at 37 degrees C in a few days, whereas inside the PLGA microspheres it retained more than 55% of its activity after 21 days of incubation at 37 degrees C. In vitro release studies revealed that different release profiles (i.e., near-constant or biphasic) and release rates can be achieved by simply modifying factors in the preparation procedure such as mixing rate and volume of inner water and organic phases. Degradation studies by scanning electron microscopy and gel-permeation chromatography suggested that the mechanism responsible for protein release is mainly through matrix erosion.

Until recently, steroid hormones were believed to act only on cells containing intracellular receptors. However, recent evidence suggests that steroids have specific and rapid effects at the cellular membrane. Using whole-cell patch-clamp techniques, 17 beta-estradiol was found to reduce Ba2+ entry reversibly via Ca2+ channels in acutely dissociated and cultured neostriatal neurons. The effects were sex-specific, i.e., the reduction of Ba2+ currents was greater in neurons taken from female rats. 17 beta-Estradiol primarily targeted L-type currents, and their inhibition was detected reliably within seconds of administration. The maximum reduction by 17 beta-estradiol occurred at picomolar concentrations. 17 beta-Estradiol conjugated to bovine serum albumin also reduced Ba2+ currents, suggesting that the effect occurs at the membrane surface. Dialysis with GTP gamma S prevented reversal of the modulation, suggesting that 17 beta-estradiol acts via G-protein activation. 17 alpha-Estradiol also reduced Ba2+ currents but was significantly less effective than 17 beta-estradiol. Estriol and 4-hydroxyestradiol were found to reduce Ba2+ currents with similar efficacy to 17 beta-estradiol, whereas estrone and 2-methoxyestriol were less effective. Tamoxifen also reduced Ba2+ currents but did not occlude the effect of 17 beta-estradiol. These results suggest that at physiological concentrations, 17 beta-estradiol can have immediate actions on neostriatal neurons via nongenomic signaling pathways.

BACKGROUND

It has been proposed that hyperlipidemia contributes to the progression of renal disease. A large trial has not been performed; however, a number of small, controlled trials have been reported. We examined the effects of antilipemic agents on glomerular filtration rate and proteinuria or albuminuria in patients with renal disease.

METHODS

We used Medline, abstracts from scientific meetings, and bibliographies from recent reviews and scientific reports to locate pertinent studies. Thirteen prospective controlled trials examining the effects of antilipemic agents on renal function, proteinuria, or albuminuria were included. Studies were published as full reports or abstracts and were at least three months in duration. For five of the studies, individual patient data were obtained. Other summary data were independently extracted from the published reports by two investigators and included study quality, subject characteristics, cause of renal disease, change in serum cholesterol, blood pressure, glomerular filtration rate, proteinuria, and albuminuria.

RESULTS

There was a lower rate of decline in glomerular filtration rate with treatment compared with controls (treated controls, 0.156 mL/min/month; 95% CI, 0.026 to 0. 285 mL/min/month, P = 0.008). The study results were statistically homogeneous, and in a regression analysis, the effect of treatment on glomerular filtration rate did not correlate with study quality, the percentage change in cholesterol, the type of lipid-lowering agent, or the cause of renal disease. However, longer follow-up correlated with the amount of improvement in glomerular filtration rate from treatment (P = 0.007). There was a tendency for a favorable effect of treatment on protein or albumin excretion [Ln (treatment) - Ln (control) = -0.248, 95% CI, -0.562 to 0.064, P = 0. 077]. However, these results were statistically heterogeneous between studies (P < 0.001). No obvious explanation for this heterogeneity was apparent in a regression analysis examining potential reasons for differences in study results.

CONCLUSIONS

Lipid reduction may preserve glomerular filtration rate and may decrease proteinuria in patients with renal disease.

We previously demonstrated the presence of advanced oxidation protein products (AOPP), a novel marker of oxidative stress in the plasma of uremic patients receiving maintenance dialysis. The present study in a cohort of 162 uremic patients showed that plasma concentrations of AOPP increased with progression of chronic renal failure and were closely related to advanced glycation end products (AGE)-pentosidine (r = 0.52, p < 0.001), taken as a marker of AGE. In vivo, the relevance of AOPP and AGE-pentosidine in monocyte-mediated inflammatory syndrome associated with uremia was evidenced by close correlations between AOPP or AGE-pentosidine and monocyte activation markers, including neopterin, IL-1R antagonist, TNF-alpha, and TNF soluble receptors (TNF-sR55 and TNF-sR75). To determine the mechanisms by which AOPP and AGE could be directly involved in monocyte activation, AOPP-human serum albumin (HSA) and AGE-HSA were produced in vitro by treating HSA with oxidants or glucose, respectively. Spectroscopic analysis confirmed that AOPP-HSA contains carbonyls and dityrosine. Both AOPP-HSA and AGE-HSA, but not purified dityrosine, were capable of triggering the oxidative burst of human monocytes in cultures. The AOPP-HSA-induced respiratory burst was dependent on the chlorinated nature of the oxidant and on the molar ratio HSA/HOCI. Collectively, these data first demonstrate that AOPP act as a mediator of oxidative stress and monocyte respiratory burst, which points to monocytes as both target and actor in the immune dysregulation associated with chronic uremia.

Optic nerve transection in adult rats results in the death of approximately 50% of the axotomized retinal ganglion cells (RGCs) by 1 week and nearly 90% by 2 weeks after injury. The capacity of brain-derived neurotrophic factor (BDNF) to prevent this early, severe loss of RGCs was investigated in vivo by intravitreal injections of BDNF [5 micrograms in 5 microliters of bovine serum albumin/phosphate-buffered saline (BSA/PBS)] or vehicle (5 microliters of BSA/PBS). Using quantitative anatomical techniques, we show that (i) all RGCs survived 1 week after a single injection of BDNF at the time of axotomy. (ii) RGC densities decreased in the BDNF-treated retinas by 2 weeks but remained significantly greater than in the untreated controls. (iii) An enhanced RGC survival was obtained with single injections of BDNF from 6 days before to 5 days after axotomy. (iv) Repeated injections resulted in greater numbers of surviving RGCs, an effect that declined to undetectable levels by 6 weeks. (v) There were indications for an endogenous local source of trophic support whose expression was triggered by ocular injury, particularly to the anterior part of the eye. (vi) With multiple BDNF injections, there was profuse axonal sprouting around the optic disc. This remarkable intraretinal growth was not, however, reflected in increased RGC innervation of the peripheral nerve grafts, which are known to facilitate regeneration when used as optic nerve substitutes.

Human serum albumin (HSA) is an abundant plasma protein that is responsible for the transport of fatty acids. HSA also binds and perturbs the pharmacokinetics of a wide range of drug compounds. Binding studies have revealed significant interactions between fatty acid and drug-binding sites on albumin but high-resolution structural information on ligand binding to the protein has been lacking. We report here a crystallographic study of five HSA-fatty acid complexes formed using saturated medium-chain and long-chain fatty acids (C10:0, C12:0, C14:0, C16:0 and C18:0). A total of seven binding sites that are occupied by all medium-chain and long-chain fatty acids have been identified, although medium-chain fatty acids are found to bind at additional sites on the protein, yielding a total of 11 distinct binding locations. Comparison of the different complexes reveals key similarities and significant differences in the modes of binding, and serves to rationalise much of the biochemical data on fatty acid interactions with albumin. The two principal drug-binding sites, in sub-domains IIA and IIIA, are observed to be occupied by fatty acids and one of them (in IIIA) appears to coincide with a high-affinity long-chain fatty acid binding site.

BACKGROUND

Hypertension may play an important role in the pathogenesis of the excess cardiovascular and cerebrovascular (CV) morbidity observed in hemodialysis patients (HD). However, the optimal blood pressure (BP) range for HD patients has not been defined. We postulated that there is a "U" curve relationship between BP and CV mortality. To explore this hypothesis we studied 5,433 HD patients in Dialysis Clinic Inc., a large not-for-profit chain, over a five year period.

METHODS

Cox regression, with fixed and time-varying covariates, was used to assess the effect of systolic blood pressure (SBP) and diastolic blood pressure (DBP), pre- and post-dialysis, on CV mortality, while adjusting for age, gender, ethnicity, primary cause of end-stage renal disease, Kt/V, serum albumin, and antihypertensive medications.

RESULTS

The overall impact of BP on CV mortality was modest. Pre-dialysis, neither systolic nor diastolic hypertension were associated with an increase in CV mortality. Post-dialysis, SBP>> or = 180 mm Hg (RR = 1.96, P < 0.015) and DBP>> or = 90 mm Hg (RR = 1.73, P < 0.05) were associated with increased CV mortality. Low SBP (SBP < 110 mm Hg) was associated with increased CV mortality, pre- and post-dialysis.

CONCLUSIONS

The results suggest the presence of a "U" curve relationship between SBP post-dialysis and CV mortality in HD patients.

Human neutrophils contain a family of microbicidal peptides known as defensins. One of these defensins, human neutrophil peptide (HNP)-1, was purified, and its ability to directly inactivate several viruses was extensively tested. Herpes simplex virus (HSV) types 1 and 2, cytomegalovirus, vesicular stomatitis virus, and influenza virus A/WSN were inactivated by incubation with HNP-1. Two nonenveloped viruses, echovirus type 11 and reovirus type 3, were resistant to inactivation. Purified homologous peptides HNP-2 and HNP-3 were found to have HSV-1-neutralizing activities approximately equal to that of HNP-1. Inactivation of HSV-1 by HNP-1 depended on the time, temperature, and pH of incubation. Antiviral activity was abrogated by low temperature or prior reduction and alkylation of the defensins. Addition of serum or serum albumin to the incubation mixtures inhibited neutralization of HSV-1 by HNP-1. We used density gradient sedimentation techniques to demonstrate that HNP-1 bound to HSV-1 in a temperature-dependent manner. We speculate that binding of defensin peptides to certain viruses may impair their ability to infect cells.