Subcutaneous immunization with a novel immunogenic candidate (urease) confers protection against Brucella abortus and Brucella melitensis infections

Brucellosis is a world prevalent endemic illness that is transmitted from domestic animals to humans. Brucella spp. exploits urease for survival in the harsh conditions of stomach during the gastrointestinal infection. In this study, we examined the immune response and the protection elicited by using recombinant Brucella urease (rUrease) vaccination in BALB/c mice. The urease gene was cloned in pET28a and the resulting recombinant protein was employed as subunit vaccine. Recombinant protein was administered subcutaneously and intraperitoneally. Dosage reduction was observed with subcutaneous (SC) vaccination when compared with intraperitoneal (IP) vaccination. rUrease induced mixed Th1–Th2 immune responses with high titers of specific IgG1 and IgG2a. In lymphocyte proliferation assay, splenocytes from IP and SC‐vaccinated mice displayed a strong recall proliferative response with high amounts of IL‐4, IL‐12 and IFN‐γ production. Vaccinated mice were challenged with virulent Brucella melitensis, B. abortus and B. suis. The SC vaccination route exhibited a higher degree of protection than IP vaccination (p value ≤ 0.05). Altogether, our results indicated that rUrease could be a useful antigen candidate for the development of subunit vaccines against brucellosis.     

A liver transplant center experience with liver dialysis in the management of patients with fulminant hepatic failure: a preliminary report

Among extracorporeal liver support devices, liver dialysis is cleared by the U.S. Food and Drug Administration to be used for the management of fulminant hepatic failure (FHF). The outcomes of patients following liver dialysis need to be clearly evaluated. Among the 25 patients with FHF admitted to the Liver ICU between May 2000 and November 2002, 12 underwent liver dialysis, including 6 men and 6 women, of mean age 32 years. The causes of FHF were identified as acetaminophen (n = 10), herbal medications (n = 1) and autoimmune disease (n = 1). At presentation, the mean total bilirubin was 9.35 mg/dL (range, 0 to 1.3), mean ALT 3015 U/L (range, 0 to 48), mean AST 3457 (range, 0 to 42), mean ammonia 98 micromol/L (range, 10 to 60) and mean INR 1.88. A control group including 13 patients (2 men and 11 women), of mean age 27.8 years mean total bilirubin 5.66, mean ALT 3494, mean AST 3528, mean ammonia 113 and mean INR 3, were not treated with liver dialysis, due to the lack of machine availability or physician's choice. The causes of FHF were acute hepatitis B (n = 1), acetaminophen (n = 10) or unknown (n = 2). There was no statistically significant difference in the baseline characteristics of the two groups (P >.05). Among the liver dialysis group, 1 patient died, 2 underwent OLTx, and 9 were discharged home. Among the control group; 4 patients died, 2 underwent OLTx, and 7 were discharged home. Preliminary results seem to support survival benefit among patients who underwent liver dialysis compared to non-liver dialysis; however, further randomized control trials are warranted to verify this observation.     

A comprehensive view of sex-specific issues related to cardiovascular disease

Cardiovascular disease (CVD) is the leading cause of mortality in women. In fact, CVD is responsible for a third of all deaths of women worldwide and half of all deaths of women over 50 years of age in developing countries. The prevalence of CVD risk factor precursors is increasing in children. Retrospective analyses suggest that there are some clinically relevant differences between women and men in terms of prevalence, presentation, management and outcomes of the disease, but little is known about why CVD affects women and men differently. For instance, women with diabetes have a significantly higher CVD mortality rate than men with diabetes. Similarly, women with atrial fibrillation are at greater risk of stroke than men with atrial fibrillation. Historically, women have been underrepresented in clinical trials. The lack of good trial evidence concerning sex-specific outcomes has led to assumptions about CVD treatment in women, which in turn may have resulted in inadequate diagnoses and suboptimal management, greatly affecting outcomes. This knowledge gap may also explain why cardiovascular health in women is not improving as fast as that of men. Over the last decades, mortality rates in men have steadily declined, while those in women remained stable. It is also becoming increasingly evident that gender differences in cultural, behavioural, psychosocial and socioeconomic status are responsible, to various degrees, for the observed differences between women and men. However, the interaction between sex-and gender-related factors and CVD outcomes in women remains largely unknown.     

Compositional Analysis of Extracellular Aggregates in the Eyes of Patients With Exfoliation Syndrome and Exfoliation Glaucoma

PurposeExfoliation syndrome (XFS) is a condition characterized by the production of insoluble fibrillar aggregates (exfoliation material; XFM) in the eye and elsewhere. Many patients with XFS progress to exfoliation glaucoma (XFG), a significant cause of global blindness. We used quantitative mass spectrometry to analyze the composition of XFM in lens capsule specimens and in aqueous humor (AH) samples from patients with XFS, patients with XFG and unaffected individuals.MethodsPieces of lens capsule and samples of AH were obtained with consent from patients undergoing cataract surgery. Tryptic digests of capsule or AH were analyzed by high-performance liquid chromatography–mass spectrometry and relative differences between samples were quantified using the tandem mass tag technique. The distribution of XFM on the capsular surface was visualized by SEM and super-resolution light microscopy.ResultsA small set of proteins was consistently upregulated in capsule samples from patients with XFS and patients with XFG, including microfibril components fibrillin-1, latent transforming growth factor-β–binding protein-2 and latent transforming growth factor-β–binding protein-3. Lysyl oxidase-like 1, a cross-linking enzyme associated with XFS in genetic studies, was an abundant XFM constituent. Ligands of the transforming growth factor-β superfamily were prominent, including LEFTY2, a protein best known for its role in establishing the embryonic body axis. Elevated levels of LEFTY2 were also detected in AH from patients with XFG, a finding confirmed subsequently by ELISA.ConclusionsThis analysis verified the presence of suspected XFM proteins and identified novel components. Quantitative comparisons between patient samples revealed a consistent XFM proteome characterized by strong expression of fibrillin-1, lysyl oxidase-like-1, and LEFTY2. Elevated levels of LEFTY2 in the AH of patients with XFG may serve as a biomarker for the disease.     

Enhanced detection of normal retinal nerve-fiber striations using a charge-coupled device and digital filtering

We used a 1024 × 1024 pixel, 15-m, 16-bitencoding, multi-pin-phase charge-coupled device (CCD) to obtain images of the normal human retinal nerve fiber layer. This device, which operates at room temperature, offers significantly better signal-to-noise ratio, linearity, and dynamic range than do photographic film, video imaging techniques, or commercially available CCDs. We demonstrate the use of a nonlinear digital filter, together with filter windows, that enhances fine detail of NFL striations, while suppressing noise, in limited areas of the CCD images. High-sensitivity imaging of this type, together with appropriate digital processing, may prove useful in diagnosing and following nerve-fiber-layer damage due to glaucoma.None of the authors has any commercial or proprietary interest in any product or company mentioned in this paper.     

The effect of total plasma exchange on fulminant hepatic failure

Total plasma exchange (TPE) corrects coagulopathy in patients with liver disease and removes hepatotoxins/cytokines. This improvement is transient but can be used as a bridge until an organ is identified for liver transplantation (LTx) or the liver itself regenerates. Our aim was to retrospectively assess the efficacy of TPE in fulminant hepatic failure (FHF) and its impact on liver function tests. Between 1995-2001, 39 patients with FHF who had undergone TPE were reviewed. FHF was defined according to the O'Grady criteria based on the duration of encephalopathy as well as jaundice. TPE was performed using the Cobe Spectra TPE (Gambro) in Liver Intensive Care Unit, continued on a daily basis, until either adequate clinical response was achieved, the patient expired, or transplantation occurred. INR, PTT, Fibrinogen, ALT, AST, GGT, BUN, Ammonia, and Total Bilirubin were analyzed before and after TPE. Student's t-test and chi-square test and ANOVA were used for statistical analysis. Thirty-nine patients with FHF (31 females, 8 males with mean age of 32.3, range: 7-64) underwent TPE. Coagulopathy, hyperbilirubinemia, hyperammonemia were significantly improved (P < 0.05). Twenty-one patients survived (54%), 12 required LTx, and 18 patients (including one after LTx) expired. TPE was found to be significantly effective for correction of coagulopathy and improvement of liver tests. This intervention can be considered for temporary liver support until recovery or liver transplantation.     

Akt and hypoxia-inducible factor-1 independently enhance tumor growth and angiogenesis

Recent reports have suggested that phosphatidylinositol 3-kinase/Akt signaling can induce angiogenesis and tumor growth by activating the hypoxia-inducible factor-1 (HIF-1). However, the absence of specific biochemical inhibitors of HIF-1 signaling has prevented a direct test of the requirement for HIF-1 activity in Akt-dependent tumorigenesis. To genetically test the relationship between HIF-1 and Akt, activated Akt was expressed in a hepatoma cell line lacking HIF-1. Akt expression was associated with a dramatic increase in tumor size, despite the absence of HIF-1. Tumor size was not further increased in cells with reconstituted HIF-1 activity, indicating that the effects of Akt on tumorigenesis were not limited by the absence of HIF-1. Increased tumor size in Akt-expressing, HIF-deficient cells was associated with vascular endothelial growth factor secretion and tumor vascularization. In addition to vascular endothelial growth factor production, Akt also conferred a cell-autonomous competitive advantage to tumor cells in an in vivo competition experiment. Thus, Akt has potent, HIF-1-independent oncogenic and angiogenic activities.