Citations

Atherogenesis is the pathobiological process, which underlies atherosclerotic cardiovascular disease and evolves in the 3 stages of initiation, progression, and complication to clinical significance. Of note, this process is associated with neovascularization, and it was not until recently that the implications of angiogenesis in atherogenesis were delineated. This article gives an updated overview on this topic and briefly reflects on the similarities with neovessel formation in carcinogenesis.

Purpose Hot flashes can cause significant morbidity in postmenopausal women undergoing or finished with breast cancer treatment. Black cohosh has been used to treat hot flashes, but definitive clinical data about efficacy have been equivocal. Methods A double-blind, randomized, cross-over clinical trial with two 4-week periods, was used to study the efficacy of black cohosh (1 capsule, Cimicifuga racemosa 20 mg BID) for the treatment of hot flashes in women. Participants kept a daily hot flash diary during a baseline week and then during two 4-week crossover treatment periods. Hot flash scores were measured by assigning points (1 to 4 for mild to very severe) to each hot flash based on severity and then adding the points for a given time period. Results Between October 31, 2003, to March 4, 2004, 132 patients were randomly assigned. Toxicity was minimal and not different by treatment group. Patients receiving black cohosh reported a mean decrease in hot flash score of 20% (comparing the fourth treatment week to the baseline week) compared with a 27% decrease for patients on placebo (P = .53). Mean hot flash frequency was reduced 17% on black cohosh and 26% on placebo (P = .36). Patient treatment preferences were measured after completion of both treatment periods by ascertaining which treatment period, if any, the patient preferred. Thirty-four percent of patients preferred the black cohosh treatment, 38% preferred the placebo, and 28% did not prefer either treatment. Conclusion This trial failed to provide any evidence that black cohosh reduced hot flashes more than the placebo.

Objective—The ubiquitin-proteasome system is the principal degradation route of intracellular and oxidized proteins, thus regulating many cellular processes conceivably important for atherosclerosis. The aim of this study was to evaluate the activity of ubiquitin-proteasome system in human carotid artery plaques in relation to oxidative stress and clinical manifestation.Methods and Results—In carotid endarterectomy specimens from 83 asymptomatic and 94 symptomatic patients, content of ubiquitin, ubiquitin conjugates, matrix metalloproteases, and NADPH-oxidase-p67 was evaluated by immunoblotting; proteolytic proteasome activity by fluorometric assay; single and double immunostaining for ubiquitin conjugates, 3-nitrotyrosine, apoptosis, smooth muscle α-actin, and macrophage CD-68, as well as Sirius Red staining for collagen were performed. Compared with asymptomatic patients, symptomatic patients showed a more unstable plaque phenotype, an increased degree of apoptosis, a significantly higher ubiquitin conjugates content (17.72±1.36 versus 10.99±1.04;P<0.001), and lower proteasome activity (5.01±0.70 versus 9.41±1.19 nmol AMC/mg protein/min;P<0.01). Ubiquitin conjugates content was directly correlated to NADPH-p67 and degree of apoptosis. Immunostaining revealed colocalization of ubiquitin conjugates and 3-nitrotyrosine, and accumulation of ubiquitin conjugates in smooth muscle cells and macrophages.Conclusions—In human carotid plaques increased oxidative stress is associated with inhibition of the proteasome activity and accumulation of ubiquitin conjugates, particularly in symptomatic patients. These results suggest a possible role of the ubiquitin-proteasome system in influencing plaque stability.

Abstract Human long DNA in stool may reflect nonapoptotic exfoliation and has been used as a colorectal cancer (CRC) marker. Targeting human-specific Alu repeats represents a logical but untested approach. A real-time Alu PCR assay was developed for quantifying long human DNA in stool and evaluated in this study. The accuracy and reproducibility of this assay and the stability of long DNA during room temperature fecal storage were assessed using selected patient stools and stools added to human DNA. Thereafter, long DNA levels were determined in blinded fashion from 18 CRC patients and 20 colonoscopically normal controls. Reproducibility of real-time Alu PCR for quantifying fecal long DNA was high (r2 = 0.99; P &lt; 0.01). Long DNA levels in nonbuffered stools stored at room temperature fell a median of 75% by 1 day and 81% by 3 days. An EDTA buffer preserved DNA integrity during such storage. Human long DNA was quantifiable in all stools but was significantly higher in stools from CRC patients than from normal controls (P &lt; 0.05). At a specificity of 100%, the sensitivity of long DNA for CRC was 44%. Results indicate that real-time Alu PCR is a simple method to sensitively quantify long human DNA in stool. This study shows that not all CRCs are associated with increased fecal levels of long DNA. Long DNA degrades with fecal storage, and measures to stabilize this analyte must be considered for optimal use of this marker. (Cancer Epidemiol Biomarkers Prev 2006;15(6):1115–9)

Dynamin is a 100-kDa microtubule-activated GTPase originally isolated from mammalian brain that has been proposed to be crucial in the early steps of endocytosis. Previous studies on the primary structure, biochemical properties, and functional role of dynamin indicated that it was neuron-specific. However, using an antibody against a synthetic peptide representing an enzymatic region of rat brain dynamin (D100), we identified a 100-kDa protein doublet in rat liver, suggesting that dynamin exists as different isoforms that are distinct from the brain counterpart. We then initiated a search for distinctive dynamin isoforms with antibodies and cDNA probes. A 500-bp PCR-generated cDNA probe corresponding to the enzymatic region of the rat brain dynamin-encoding gene was used to isolate six overlapping clones from a rat liver cDNA library that together span the complete coding sequence of another dynamin gene, "Dyn2." Sequence analyses reveal that dynamin 2 (Dyn2) is 75% identical to brain dynamin at the DNA level and is 79% identical at the protein level. By Northern blot analysis and isoform-specific PCR, Dyn2 was found ubiquitously in adult rat tissues as two transcripts of 3.5 kb and 4 kb; the highest levels were found in testis. These results indicate that dynamin proteins are encoded by at least two genes expressed differentially in mammalian tissues and that the expression of Dyn2, and not of brain dynamin, accounts for the ubiquitous distribution of dynamin in rat tissues.

The albumin (Alb), IgG, and IgM concentrations in the endoneurium of fascicular sural nerve biopsy samples were evaluated in controls (n = 9 or 10), diabetic patients without neuropathy (n = 6), and diabetic patients with polyneuropathy (n = 17 or 18). These values were significantly increased in diabetic patients with and without neuropathy when expressed both per endoneurial dry weight or endoneurial total protein compared to biopsy samples from healthy controls. When these concentrations, expressed per endoneurial total protein, were related to plasma concentrations similarly expressed, the resulting blood-nerve barrier (BNB) indices were significantly increased for Alb (6.1 times; P less than 0.00001), IgG (4.9 times; P = 0.00037), and IgM (2.7 times; P = 0.015). The diabetic patients without neuropathy (defined as having an index of pathology of greater than 0.65; a measure of the severity of the pathological abnormality based on morphological criteria) also had significant increases in two of these BNB indices that were intermediate between the diabetic neuropathy patients and controls (Alb, 3.9 times controls; P = 0.00002: IgG, 4.6 times controls; P = 0.00016: IgM, 1.8 times controls; not significant). No correlations were observed between the endoneurial concentrations of these plasma proteins or the BNB indices and the index of pathology, suggesting that these increases in endoneurial plasma proteins precede the pathologic alterations. The increased values for the diabetics in the absence of pathological abnormalities may prove useful in predicting neuropathic complications. The ratio of the IgG-BNB index to the Alb-BNB index was decreased 19%, and the ratio of the IgM-BNB index to the Alb-BNB index was decreased 56% in diabetic neuropathy patients compared to controls. Although the IgG and IgM concentrations are increased in the diabetic endoneurium, the Alb increase is greater and a mechanism other than size indiscriminate extravasation of plasma proteins, therefore, is suggested. Morphometric assessment of the endoneurial compartments, which would be expected to contain these plasma proteins, suggests that they are not altered in diabetic neuropathy; hence, it is hypothesized that the observed increase in endoneurial concentration of these plasma proteins results from altered transport through the endothelial or perineurial barrier, which supports an underlying vascular mechanism in the development of diabetic polyneuropathy.