The development of fibrocartilage in the rat intervertebral disc

The development of fibrocartilage in rat lumbar intervertebral discs has been correlated with an immunohistochemical analysis of the changing distribution of extracellular matrix components. Disc anlagen were first recognised by embryonic day 14 as segmental cell condensations. By E16, the notochord formed a series of bulges, each representing a future nucleus pulposus, and the annulus fibrosus had differentiated in the disc anlagen. The inner part of the annulus was composed of cartilage which linked that of adjacent vertebral bodies. The outer part was fibroblastic, with layers of parallel fibroblasts. The long axes of the cells in successive layers lay at an angle of approximately 90° to each other. This criss-cross orientation of cells preceded the oriented deposition of collagen fibres to form the lamellae. Disc anlagen were immunolabelled weakly for types I and III collagen, chondroitin 6-sulphate and dermatan sulphate. Later tissue differentiation was marked by the appearance of type II collagen, chondroitin 4-sulphate and keratan sulphate in the inner annulus. These components also appeared in the outer annulus, but only in adult animals, and indicated metaplastic change in the lamellar fibroblasts. Fibrocartilage in the nucleus pulposus was only seen in old animals, and the origin of the tissue was less clear. However, the fibrocartilage cells appeared to be derived from the cartilage end plate and/or from the inner annulus. We conclude that fibrocartilage in the intervertebral disc is derived from several sources and that the radial distribution patterns of extracellular matrix components in the adult disc are explained by the embryonic origins of its parts.     

CD4 monoclonal antibody pairs for immunosuppression and tolerance induction

A pair of rat anti-mouse CD4 monoclonal antibodies (mAb) have been selected which bind to different epitopes of the molecule. Both the mAb are rat IgG2b and show clear synergistic activity in complement lysis in vitro. When injected together in vivo, they exhibit an improved immunosuppressive effect, compared to each antibody alone, on allogeneic graft rejection, humoral responses and on tolerance induction. Limiting dilution analysis indicates that the in vivo depletion of interleukin 2-producing cells is improved using both mAb by 2-3-fold over that obtained with the individual antibodies. As little as 60 ng per mouse of the CD4 antibody pair was sufficient to allow the induction of tolerance to human gamma-globulin, even without elimination of the CD4+ cells. The results suggest that appropriate antibody pairs may be good candidates for effective immunosuppressive serotherapy in man.     

LIN-39/Hox triggers cell division and represses EFF-1/fusogen-dependent vulval cell fusion

General mechanisms by which Hox genes establish cell fates are known. However, a few Hox effectors mediating cell behaviors have been identified. Here we found the first effector of LIN-39/HoxD4/Dfd in Caenorhabditis elegans. In specific vulval precursor cells (VPCs), LIN-39 represses early and late expression of EFF-1, a membrane protein essential for cell fusion. Repression of eff-1 is also achieved by the activity of CEH-20/Exd/Pbx, a known cofactor of Hox proteins. Unfused VPCs in lin-39(-);eff-1(-) double mutants fail to divide but migrate, executing vulval fates. Thus, lin-39 is essential for inhibition of EFF-1-dependent cell fusion and stimulation of cell proliferation during vulva formation. Supplemental material is available at http://www.genesdev.org.     

Cytokeratin polypeptide expression in a cloacogenic carcinoma and in the normal anal canal epithelium

Summary The aim of the present study was to explore the origin of cloacogenic carcinoma in the anal canal by immunohistochemical methods. We compared cytokeratin polypeptide expression of a cloacogenic carcinoma to normal anal epithelia, to anal squamous cell carcinoma and to basal and squamous cell carcinoma of the skin, using a battery of monoclonal anti-cytokeratin, polypeptide-specific antibodies. Our results indicate that cloacogenic carcinoma expresses cytokeratin polypeptides similar to those of the basal layer of anal squamous epithelium, of the anal transitional zone epithelium and of a layer of basal cells in the anal glands. Thus we concluded that each of the above cell types may be the cell of origin of cloacogenic carcinoma.     

Multiple macrodontic multituberculism

Ekman-Westborg and Julin [1974: Oral Surg 38:217-222], described multiple macrodontia and multituberculism affecting the teeth without other anomalies (E-WJ). We describe a Chilean case in a 12-year-old with the typical dental alterations and with histopathologic findings that include absence of predentin layer and prominent reduced enamel epithelium. E-WJ is not a syndrome and we propose "multiple macrodontic multituberculism" as a better name for this anomaly of uncertain etiology affecting only the crowns of the teeth.     

Aspirin-Interleukin-3 Interrelationships in Patients With Anti-Phospholipid Syndrome

PROBLEM: Previously we reported on the generation of experimental anti-phospholipid syndrome (APS) in mice. These models were employed to evaluate the efficacy of various novel therapeutic modalities including interleukin-3 (IL-3) and low dose aspirin. The efficacy of the latter was found to be interrelated. Low dose aspirin is capable of inhibiting the activity of the enzyme cyclooxygenase which is responsible for the metabolism of arachidonic acid towards the production of prostaglandins. This shifts the metabolism of arachidonic acid to the other pathway and leads to an overproduction of leukotrienes. The leukotrienes act as stimulators of IL-3 production, a positive cytokine in pregnancy which enhances placental and fetal development. In the current study we evaluated the IL-3 levels in pregnant women with APS and expanded our knowledge on the interrelationships between aspirin, arachidonic acid metabolites and IL-3 in the human system. METHODS: IL-3 levels were recorded in the serum of pregnant women with APS and compared to a control pregnant group. In addition peripheral blood mononuclear cells from healthy subjects were incubated with different concentrations of aspirin or with arachidonic acid metabolites (Leukotriene B4, C4 or PGE₂), and IL-3 production in the culture fluids was evaluated. RESULTS: Serum level of IL-3 in pregnant patients with primary APS, APS secondary to SLE and SLE was lower in comparison to the control group. The in vitro studies revealed that only low dose aspirin (10 mg/μl) stimulated IL-3 production while higher doses of the drug failed to induce the cytokine generation. Leukotriene B4 and C4 were stimulatory whereas PGE₂ acted as inhibitor of IL-3 production. CONCLUSIONS: The serum level of IL-3 is decreased to pregnant women with primary or secondary APS. Low dose aspirin is capable of stimulating EL-3 production in vitro most probably through an elevation of leukotriene production, which may explain its beneficial activity in preventing the manifestations of APS.     

BEAUTY and the breast: is adjuvant chemotherapy the right time for a beauty boost? Lessons learned from a large randomized controlled trial

Quality of Life Research - Beauty care (BTC) is offered at many cancer hospitals having a great uptake among patients. Nevertheless, its benefits in the Quality of life (QoL) of cancer survivors...     

Variations in Safe Sleep Practices and Beliefs: Knowledge is not Enough

Maternal and Child Health Journal - Sleep-related infant deaths in the District of Columbia (DC) varies, with rates in certain geographical areas three times higher than DC and seven times higher...