Ten-year clinical assessment of three posterior resin composites and two amalgams

OBJECTIVE: The long-term clinical performance of three posterior resin composites and two amalgams was assessed. METHOD AND MATERIALS: Thirty Class II restorations each of P-30, Occlusin, Clearfil Posterior (composites), New True Dentalloy, and Solila Nova (amalgams) were placed. Reviews took place at 6 months and at 1, 2, 3, 4, 5, and 10 years. At each visit the gingival condition, the contact point status, and the presence of ledges, gaps, or recurrent caries were assessed. The color match, cavosurface marginal stain, general surface stain, tarnish, and corrosion were also scored where applicable. Epoxy resin replicas were used to measure the maximum depth of wear. RESULTS: After 10 years, there had been corrosion of both the high- and low-copper amalgams and a slight deterioration in color match of a number of composite restorations. Eighteen (of 20) Occlusin restorations had obvious cavosurface marginal stain, attributed to staining of the unfilled bonding resin layer. Statistical analysis indicated that New True Dentalloy, Solila Nova, and Clearfil-P exhibited significantly less wear than Occlusin and P-30. None of the restorations examined at the 10-year recall required replacement. CONCLUSION: The five materials, placed in a dental school environment, provided adequate clinical service for 10 years.     

Well-done meat intake and the risk of breast cancer

BACKGROUND: Heterocyclic amines, mutagens formed in meats cooked at high temperatures, have been demonstrated as mammary carcinogens in animals. We conducted a nested, case-control study among 41836 cohort members of the Iowa Women's Health Study to evaluate the potential role of heterocyclic amines and intake of well-done meat in the risk for human breast cancer. METHODS: A questionnaire was mailed to individuals in the cohort who had breast cancer diagnosed during the period from 1992 through 1994 and a random sample of cancer-free cohort members to obtain information on usual intake of meats and on meat preparation practices. Color photographs showing various doneness levels of hamburger, beefsteak, and bacon were included. Multivariate analysis was performed on data from 273 case subjects and 657 control subjects who completed the survey. RESULTS: A dose-response relationship was found between doneness levels of meat consumed and breast cancer risk. The adjusted odds ratios (ORs) for very well-done meat versus rare or medium-done meat were 1.54 (95% confidence interval [CI]=0.96-2.47) for hamburger, 2.21 (95% CI=1.30-3.77) for beef steak, and 1.64 (95% CI=0.92-2.93) for bacon. Women who consumed these three meats consistently very well done had a 4.62 times higher risk (95% CI=1.36-15.70) than that of women who consumed the meats rare or medium done. Risk of breast cancer was also elevated with increasing intake of well-done to very well-done meat. CONCLUSIONS: Consumption of well-done meats and, thus, exposures to heterocyclic amines (or other compounds) formed during high-temperature cooking may play an important role in the risk of breast cancer.     

Lyme arthritis synovial gamma delta T cells respond to Borrelia burgdorferi lipoproteins and lipidated hexapeptides

Lyme arthritis synovial fluid contains a large proportion of gamma delta T cells that proliferates upon stimulation with the causative spirochete, Borrelia burgdorferi. A panel of Borrelia-reactive gamma delta T cell clones was derived from synovial fluid of two patients with Lyme arthritis. Each of six gamma delta clones from one patient used the V delta 1 TCR segment but had otherwise unique CDR3 sequences and diverse V gamma segment usage. Stimulation of the V delta 1 clones was optimal in the presence of Borrelia, dendritic cells, and exogenous IL-2, which was reflected by proliferation, TCR down-modulation, as well as induction of CD25 and Fas ligand expression. Stimulation by B. burgdorferi-pulsed dendritic cells withstood chemical fixation and was not restricted to class I or class II MHC, CD1a, CD1b, or CD1c. In contrast, anti-gamma delta antibody potently inhibited proliferation. Extraction of B. burgdorferi lipoproteins with Triton X-114 enriched for the stimulatory component. This was confirmed using lipidated vs nonlipidated hexapeptides of Borrelia outer surface proteins. These observations suggest that synovial V delta 1 T cells may mediate an innate immune response to common lipoprotein products of spirochetes.     

DNA replication is completed in Saccharomyces cerevisiae cells that lack functional Cdc14, a dual-specificity protein phosphatase

A 35-year-old man affected with pulmonary sarcoidosis had a 12-year history of fatigue and pain in the limbs, with normal neurological examination, except for diffusely absent deep tendon reflexes. Muscle biopsy samples showed multiple noncaseating granulomas, most prominent around the intramuscular nerves, with predominance of CD4+ cells. Intramuscular nerve bundles surrounded by granulomas were immunolabelled with laminin alpha1, alpha2, beta1 and gamma1 chain, and collagen IV. Sural nerve biopsy samples were normal. This patient showed a unique histopathological pattern of sarcoid neuromyopathy characterized by distribution of granulomas or infiltrating cells around intramuscular nerve fibers. The clinical picture, restricted to nonspecific symptoms of fatigue and myalgia, and loss of deep tendon reflexes, correlated well with the selective localization of sarcoid lesions in contiguity with the intramuscular nerves. To our knowledge, this peculiar clinico-pathological correlation has not been reported previously.     

The small-cell variant of mycosis fungoides. A clinicopathological and quantitative electron microscopic study on 14 patients

Small-cell variants of Sézary syndrome and mycosis fungoides (MF) have been described. However, in these studies the nuclear area of the small-cell variant of MF (SC-MF) as compared to histological classical MF (CL-MF) was not characterized objectively by quantitative electron microscopy. In a 14-year follow-up period, of a total of 76 patch/plaque stage MF patients seen in the Department of Dermatology of the University Hospital Utrecht, 14 (18%) had an infiltrate composed of atypical lymphocytes characterized by a distinctly smaller cell diameter and smaller, hyperchromatic, deeply indented nuclei as compared to the usual cell type of MF. The aim of the investigation was to confirm this observation objectively using quantitative electron microscopy (morphometry) and to define SC-MF as compared to CL-MF. The study was performed on the 14 patients with SC-MF, and 10 patients with clinical and histological CL-MF and 4 patients with chronic eczema. Electron micrographs of sections obtained from each biopsy were analysed by computer to produce the following data: a nuclear contour index (NCI), the mean nuclear area (MNA), the mean nuclear area of the cells above the 75th percentile (P75NA) and the percentage of cells larger than 30 microm2. The values of MNA differed significantly between patients with SC-MF and those with CL-MF (17.6 vs 23.2 microm2; P = 0.02), as did the values of P75NA (20.7 vs 27.9 microm2; P = 0.01). The NCI of the SC-MF and CL-MF patients were similar. These results are consistent with our observations that SC-MF does indeed exist.     

CD164, a novel sialomucin on CD34(+) and erythroid subsets, is located on human chromosome 6q21

CD164 is a novel 80- to 90-kD mucin-like molecule expressed by human CD34(+) hematopoietic progenitor cells. Our previous results suggest that this receptor may play a key role in hematopoiesis by facilitating the adhesion of CD34(+) cells to bone marrow stroma and by negatively regulating CD34(+) hematopoietic progenitor cell growth. These functional effects are mediated by at least two spatially distinct epitopes, defined by the monoclonal antibodies (MoAbs), 103B2/9E10 and 105A5. In this report, we show that these MoAbs, together with two other CD164 MoAbs, N6B6 and 67D2, show distinct patterns of reactivity when analyzed on hematopoietic cells from normal human bone marrow, umbilical cord blood, and peripheral blood. Flow cytometric analyses revealed that, on average, 63% to 82% of human bone marrow and 55% to 93% of cord blood CD34(+) cells are CD164(+), with expression of the 105A5 epitope being more variable than that of the other identified epitopes. Extensive multiparameter flow cytometric analyses were performed on cells expressing the 103B2/9E10 functional epitope. These analyses showed that the majority (>90%) of CD34(+) human bone marrow and cord blood cells that were CD38(lo/-) or that coexpressed AC133, CD90(Thy-1), CD117(c-kit), or CD135(FLT-3) were CD164(103B2/9E10)+. This CD164 epitope was generally detected on a significant proportion of CD34(+)CD71(lo/-) or CD34(+)CD33(lo/-) cells. In accord with our previous in vitro progenitor assay data, these phenotypes suggest that the CD164(103B2/9E10) epitope is expressed by a very primitive hematopoietic progenitor cell subset. It is of particular interest to note that the CD34(+)CD164(103B2/9E10)lo/- cells in bone marrow are mainly CD19(+) B-cell precursors, with the CD164(103B2/9E10) epitope subsequently appearing on CD34(lo/-)CD19(+) and CD34(lo/-)CD20(+) B cells in bone marrow, but being virtually absent from B cells in the peripheral blood. Further analyses of the CD34(lo/-)CD164(103B2/9E10)+ subsets indicated that one of the most prominent populations consists of maturing erythroid cells. The expression of the CD164(103B2/9E10) epitope precedes the appearance of the glycophorin C, glycophorin A, and band III erythroid lineage markers but is lost on terminal differentiation of the erythroid cells. Expression of this CD164(103B2/9E10) epitope is also found on developing myelomonocytic cells in bone marrow, being downregulated on mature neutrophils but maintained on monocytes in the peripheral blood. We have extended these studies further by identifying Pl artificial chromosome (PAC) clones containing the CD164 gene and have used these to localize the CD164 gene specifically to human chromosome 6q21.     

Colitis cystica profunda

Colitis cystica profunda is a benign disease of the colon. Its importance lies in differentiating it from mucus-producing adenocarcinoma. It has rarely been described in the surgical literature. A review of records of patients seen at the Mayo Clinic produced 66 clinical cases of localized colitis cystica profunda, and in 21 patients the diagnosis was confirmed histologically. Follow-up, which was available in all patients, ranged from 2 months to 29 years, with a mean follow-up of more than 8 years. The data suggest that local excision is the preferred initial therapy.     

A case of veno-occlusive disease of the liver in Britain associated with herbal tea consumption

Veno-occlusive disease of the liver with clinical and pathological features similar to those of the condition occurring in the Caribbean is described in a young woman resident in Britain. The diagnosis was made from liver biopsies and hepatic venography and was confirmed at necropsy. Small amounts of pyrroliziding alkaloids were recovered from a sample of mate (Paraguay) tea, owned by the patient, to which she was addicted. It seems probable that the consumption of large amounts of this tea over a period of years was the cause of the hepatic disease.