Mitogenic, chemotactic, and synthetic responses of rat periodontal ligament fibroblastic cells to polypeptide growth factors in vitro.

The mitogenic, chemotactic, and synthetic responses of rat periodontal ligament (PDL) fibroblastic cells to epidermal growth factor (EGF), transforming growth factor-beta (TGF-beta), recombinant human platelet-derived growth factor (rhPDGF)-AB, rhPDGF-BB, natural (n) PDGF-AB, and insulin-like growth factor-I (IGF-I) were examined in vitro using PDL cells obtained from the coagulum of healing tooth sockets. PDGFs and IGF-I have potent and comparable mitogenic effects on PDL fibroblastic cells. The maximum mitogenic effect of PDGFs was observed at the concentration of 10 ng/ml, whereas that of IGF-I was seen at concentrations higher than 100 ng/ml. In contrast, EGF induced moderate, and TGF-beta inhibitory mitogenic responses. The combination of rhPDGF-AB with either EGF or TGF-beta demonstrated comparable mitogenic potency, equivalent to the level of PDGF alone regardless of the mitogenic effect of other growth factors. The combination of rhPDGF-AB and IGF-I, however, showed a synergistic effect revealing the highest mitogenic effect among all individual growth factors as well as any combinations of the growth factors tested. Similarly, PDL fibroblastic cells demonstrated strong chemotactic responses to both IGF-I and PDGFs. The maximum effect was observed by IGF-I at concentrations higher than 10 ng/ml, followed by rhPDGF-BB at 0.1 ng/ml, rhPDGF-AB and nPDGF at concentrations ranging from 0.1 to 1 ng/ml. TGF-beta revealed no, and EGF slightly increased, chemotactic effects. IGF-I slightly enhanced the synthesis of total protein, whereas other factors had no significant effect. However, both rhPDGF-AB and TGF-beta stimulated collagen synthesis. On the other hand, IGF-I showed no effect on collagen synthesis, while EGF suppressed collagen synthesis. These findings suggest that rhPDGF-BB and IGF-I stimulate proliferation and chemotaxis of PDL fibroblastic cells. In addition, the combination of these growth factors further increases the mitogenic effect. rhPDGF-AB also stimulates collagen synthesis by PDL fibroblastic cells. Thus, rhPDGF-BB and IGF-I may have important roles in promotion of PDL healing, and consequently, may be useful for clinical application in periodontal regenerative procedures.     

Chemotherapy in recurrent and advanced cervical cancer.

Twenty-five patients, ranging from 21 to 61 years of age (median = 45 years), with histologically proven recurrent and advanced cervical cancer were treated with chemotherapy using a combination of bleomycin, ifosfamide, and cis-platinum (BIP). Twenty-one patients were evaluable for response. Ninety percent of patients achieved a subjective response. An objective response was noted in 14 of 21 (66.6%) patients: complete in 4 (19%) and partial in 10 (47.6%). Side effects were mainly nausea/vomiting, alopecia, myelosuppression, reversible encephalopathy, and impaired renal function. One patient died from the toxic effects of chemotherapy. These results indicate that BIP is an active combination in recurrent cervical cancer with acceptable toxicity.     

Surgical management of trismus due to Oral Submucous Fibrosis — Lysis of fibrotic bands with the KTP-532 Laser

Oral Submucous Fibrosis is an insidious, chronic disease affecting the oral cavity, sometimes the pharynx and rarely the tongue. 15 patients with Oral Submucous Fibrosis presenting with severe trismus were treated with lysis of the fibrotic bands with a KTP-532 Laser and adjunctive treatment with excellent results over a 12 month follow-up period.     

Bilateral posterior lens dislocation in Marfan's syndrome

Complete dislocation of the lens is a rare feature of Marfan's Syndrome. We observed four cases of bilateral complete posterior dislocation of the lens in established cases of Marfan's Syndrome over a one year period. An ophthalmologist may encounter infrequently, unilateral posterior dislocation in one eye and ectopia lentis in the other, but bilateral spontaneous posterior dislocation is rare. All our cases had associated vitreous degeneration with vitreous herniating into the anterior chamber. The pathogenesis of complete posterior dislocation in Marfan's Syndrome is discussed.     

A cell line from Wilms' tumour with deletion in short arm of chromosome II

A cell line (T3/73) from a Wilms' tumour has been established from a 9 month-old boy with aniridia. The tumour was removed in 1973. On histological examination a diagnosis of Wilms' tumour was made which showed undifferentiated areas, marked tubule formation and abundant striped muscle fibres. The tumour cells, which are fusiform, grew rapidly in culture without the addition of growth factors, and have undergone over 100 passages. Approximately 95% and 5% were positive for desmin and cytokeratin, respectively. The cell doubling time was 28 hr. Cytogenetic studies revealed a karyotype of 46,XY,del(11) (p12::p14). Although the cells stained very intensely with a monoclonal antibody that detects oncogene ras p 21 antigen, Southern blot analysis using c-Ha-ras as a probe failed to reveal an obvious deletion or amplification of either Ha-ras allele.     

Variability in cardiovascular and plasma norepinephrine responses to head-up tilt in healthy human subjects.

Eight healthy, young adult males underwent three separate, 10-min 70 degrees head-up tilts (HUT) over a period of nine days, in order to assess the intra- and inter-individual variability of cardiovascular and plasma norepinephrine (NE) responses to the manoeuvre. Cardiovascular parameters and plasma NE were measured in the basal state and at 2-min intervals during the HUT. The results indicate that: (1) the intra-individual variability is a smaller component of the total variability of both cardiovascular and plasma NE responses to HUT; (2) the variability in cardiovascular parameters is smaller than that in plasma NE levels, both basal and in response to postural stress; (3) there does not appear to be any difference in variability when expressed either as the maximal or the mean response to HUT; and (4) there does not appear to be an increase in the variability of the measured parameters over the duration of the HUT.