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To define the role of specific gene deletions and mutations in the development of transplant arteriosclerosis, we generated an accelerated model of the disease in mice. Carotid arteries were transplanted between B.10A(2R) (H-2h2) donor mice and C57BL/6J (H-2b) recipients and compared with arteries isografted between H-2b mice. Immunosuppressive drugs were not used. Within 7 days, the allografted carotid artery formed a neointima composed of mononuclear leukocytes (CD45+) that were predominantly monocytes or macrophages (ie, CD11b+ cells with single-lobed nuclei). CD4+ and CD8+ cells were present as well. By 30 days, the neointima became exuberant, and mononuclear leukocytes were largely replaced by smooth muscle cells. Cells staining for proliferating-cell nuclear antigen were abundantly present in the intima at both early and late time points, indicating the proliferation of mononuclear leukocytes and smooth muscle cells. The area of the intima increased from day 7 to day 30 (P < .0005), as did the number of nuclei (P = .0005), but the density of the nuclei decreased (P = .02), suggesting the formation of extracellular matrix. Six of the eight isografts formed no neointima, and in samples from the remaining two, a single layer of smooth muscle neointimal cells covered just a portion of the vessel circumference. This model, which reproduces many of the features of human transplant arteriosclerosis but at an accelerated pace, should prove useful for determining the roles in transplant arteriosclerosis of genes that code for components of immunologic and inflammatory responses.

Transplant arteriosclerosis, the major manifestation of chronic rejection, develops after allogeneic (Lewis to F344) but not syngeneic (Lewis to Lewis) rat cardiac transplantation. To identify transcriptionally regulated mediators associated with chronic cardiac rejection, we adapted the differential mRNA display technique for in vivo transplant specimens. Gene transcript patterns in four allogeneic hearts showing early signs of chronic rejection were compared with those in two syngeneic hearts exposed to the same surgical procedure but histologically normal. Twelve differentially expressed cDNA bands were identified. We improved the probability of isolating one or more allograft-specific cDNAs from a single display band by first using recovered and reamplified PCR products as probes in RNA blot analysis. cDNA fragments cloned from individual bands were then used in a second RNA blot analysis, which allowed for the correlation of specific mRNA transcripts with cDNA clones. Five cDNA clones produced time-dependent, allograft-specific hybridization. Sequence analysis demonstrated that two of these cDNAs corresponded to unknown genes, whereas the other three represented known genes not previously associated with chronic rejection. The latter group included the macrophage lectin specific for galactose/N-acetylgalactosamine (a cell-surface receptor), the nuclear P1 gene (a homologue of a yeast replication protein), and a ubiquitin-like gene. Our application of the differential display technique allowed the direct identification of potential mediators under in vivo conditions that preserve the environment of the disease process--including infiltrating cell populations critical to the inflammatory response.

On October 5 and 6, 2001, less than a month after the terrorist attacks on the United States, a conference on the Pathophysiology, Detection, and Treatment of Vulnerable Plaque was held in Boston, Mass. Nineteen scientists from around the world came together, despite the uncertainty of air travel, to continue the work against this important cause of cardiovascular disease. After the faculty dinner, Dr James Muller, Co-Director of the Vulnerable Plaque Program of the Center for the Integration of Medicine and Innovative Technology (CIMIT) and Director of Clinical Research in Cardiology at the Massachusetts General Hospital and Harvard Medical School, offered the following thoughts on cardiovascular research and the September 11, 2001, terrorist attacks. Dr Muller was one of the co-founders of International Physicians for Prevention of Nuclear War, the organization awarded the 1985 Nobel Peace Prize. The terrible violence of September 11, a day of mass murder of innocent civilians, had many consequences, some of which directly affected our collective effort to prevent death from vulnerable plaque. Specifically, I refer to the irony that September 11 started as a day to celebrate progress for the vulnerable plaque research community. Over 10 000 individuals congregated at the Transcatheter Cardiovascular Therapeutics (TCT) Conference in Washington, DC. The program included a town meeting on vulnerable plaque, one of those wonderful occasions when the scientists working in isolation come together to share progress and ideas. The event was a rare moment when one could actually feel a massive human problem slowly giving way to organized, dedicated human effort. At 8:00 AM, I gave the opening lecture, which included an overview of the topic of vulnerable and invulnerable plaques. At 8:45, while Dr Peter Fitzgerald described the use of ultrasound and OCT for the diagnosis and treatment …

The present studies were conducted to evaluate the cholesterolemic effects of whole-food diets high in stearic acid. In study no. 1, normocholesterolemic young men were fed diets high in stearic acid provided by cocoa butter (CB); oleic acid provided by olive oil (OO); linoleic acid provided by soybean oil (SO); and myristic acid (and lauric acid) provided by dairy butter (B). In study no. 2, different subjects with similar baseline characteristics were fed diets high in stearic acid provided by milk chocolate (C), CB, CB+B (4:1, MIX), and myristic (and lauric) acid provided by B. Both studies used a randomized, crossover, double-blind experimental design, and experimental subjects (n = 18 for study no. 1 and n = 15 for study no. 2) in each study consumed every diet for 26 days with a 1-month wash-out period between each experimental period. The diets provided 37% of calories from fat, of which 81% was provided by the test fat. Ten ounces (280 g) C was provided daily by the C diet. In study no. 1, the B diet was hypercholesterolemic, whereas the SO diet was hypocholesterolemic, compared with the other diets. The OO and SO diets were hypocholesterolemic compared with the CB diet. Low-density lipoprotein (LDL) cholesterol levels, in general, paralleled the changes in plasma total cholesterol levels. SO significantly decreased apolipoprotein (apo) B levels compared with the other diets. Plasma very-low density lipoprotein (VLDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and apo A-I levels were unaffected by the experimental diets.(ABSTRACT TRUNCATED AT 250 WORDS)

Macromolecular β-galactosidase substrates were prepared by attaching o-nitrophenyl-β-galactoside to carboxymethyldextran with positively charged linking groups. Almost all of the substituents were susceptible to enzymic hydrolysis by two distinct pathways. Under some conditions, there was random reaction to give a soluble product. In other conditions, in the initial stages of the reaction, most of the substituents of some, but not all, of the substrate polymers were hydrolyzed to give a product which precipitated as a second aqueous phase. Kinetics of hydrolysis were studied with respect to charge and molecular weight of both the enzyme and substrate. Factors that caused a decrease in Km favored formation of the second phase product. The reaction has similarities to the processive catalytic reactions found in naturally occurring enzyme systems with polymeric charged substrates.

We describe the use of a microconcentrator membrane with a 10,000 dalton cutoff for treating cerebrospinal fluid (CSF) specimens before electrophoresis. We also examine immunochemical methods based on radial immunodiffusion, rate nephelometry, and nephelometry at quasi-equilibrium for quantifying IgG in CSF by studying calibrator crossover, imprecision at low IgG levels, and patient correlation. Calibrator crossover studies showed that values for all standard materials agreed well with assigned. At IgG quantities lower than 30.0 mg/L, we found the radial immunodiffusion (RID) method difficult to use; the rate and quasi-equilibrium methods were reliable to 11.2 and 3.0 mg/L, respectively. Above their respective cutoffs, correlation studies revealed that all three methods compared well. We performed IgG quantification and protein electrophoresis on 40 CSF specimens from patients having non-neurologic disease, finding normal reference intervals which generally agreed with those established previously; however, the albumin, beta, and gamma electrophoretic fractions we observed differed from those reported previously.

Normal newborn infants are shown to have a higher content of ammonia in the peripheral blood than their mothers, and the high levels persist for at least 10 days after birth. The level of ammonia in the blood of parturient women is normal. Infants with idiopathic hyperbilirubinemia have abnormally high levels of ammonia in the blood. Samples of blood from the umbilical vein near the entrance of the portal vein have higher concentrations of ammonia than are found in the infant's peripheral venous blood. Therefore, blood from the portal vein seems to contain elevated levels of ammonia in the newborn. The mechanism of this is not clear. The placenta appears to remove ammonia from the blood of the fetus. The high ammonia content of stored blood, and its possible effects on the infant in exchange transfusions were investigated and are discussed. A correlation between concentrations of unconjugated bilirubin and ammonia in the blood was not found in the newborn period.

Objectives We sought to determine whether gender influences the results of paclitaxel-eluting stent implantation. Background The TAXUS-IV trial demonstrated the safety and effectiveness of the slow-release, polymer-based, paclitaxel-eluting TAXUS stent compared to bare-metal stents in patients undergoing elective coronary intervention. Whether these results are generalizable to women is not known. Methods A total of 1,314 patients with coronary lesions 10- to 28-mm long in 2.5- to 3.75-mm vessels were randomized to TAXUS stent versus bare-metal EXPRESS stents (Boston Scientific Corp., Natick, Massachusetts). Outcomes examined were stratified by gender. Results A total of 662 patients (including 187 women) were assigned to the TAXUS stent, and 652 (180 women) received the control stent. Women were older than men, and had more hypertension, diabetes, renal insufficiency, unstable angina, and heart failure, but less smoking. Among patients receiving the TAXUS stent, women compared with men had higher unadjusted one-year rates of target lesion revascularization (TLR) (7.6% vs. 3.2%, p = 0.03), though female gender was not an independent predictor of TLR (odds ratio [OR] = 1.72 [95% confidence interval (CI) 0.68 to 4.37], p = 0.25). Moreover, restenosis rates were similar in men and women treated with the TAXUS stent (8.6% vs. 7.6%, respectively, p = 0.80), as was late loss (0.22 vs. 0.23 mm, p = 0.90). Compared to control stents, treatment with the TAXUS stent in women resulted in a significant reduction in nine-month restenosis (8.6% vs. 29.2%, p = 0.0001) and one-year TLR (7.6% vs. 14.9%, p = 0.02). The only independent predictor of freedom from restenosis in women was randomization to the TAXUS stent (OR = 0.28 [95% CI 0.11 to 0.74], p = 0.01). Conclusions The benefits of the paclitaxel-eluting stent in reducing clinical and angiographic restenosis are generalizable to women.

We treated 52 mentally retarded patients with intractable seizures by adding valproic acid (VPA) to other drug regimens. Sixty-one percent improved clinically. VPA significantly reduced the frequency of generalized tonic-clonic seizures, generalized myoclonus, absence and atonic seizures. There was a significant correlation between clinical improvement and reduction of EEG paroxysmal activity.

We treated 61 patients with seizures refractory to conventional anticonvulsants by adding clorazepate to their regimen. There was some improvement of seizure control, but no overall improvement in the electroencephalogram. Improvement of seizure control was not significantly related to seizure type. No significant side effects, drug interactions, or laboratory abnormalities were noted with doses up to 3 mg per kilogram per day.