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.     

A new cell line for the production of chicken monoclonal antibody by hybridoma technology

In our previous study (Nishinaka et al., 1989), a chicken B cell line (HU3R27) deficient in thymidine kinase activity was used as a fusion partner for production of chicken monoclonal antibody. Specific antibody-producing hybridomas were initially obtained, but they soon lost the ability to produce antibody in culture. The present report documents the development of an improved fusion cell line. R27H4, for the production of chicken monoclonal antibody. This cell line was obtained by fusion of HU3R27 cells with spleen cells of immunized chicken. Fusion of R27H4 cells with spleen cells from chicken immunized by keyhole limpet hemocyanin (KLH) resulted in antibody-producing hybridomas. Subcloned hybridomas secreted highly reactive IgG and weakly reactive IgM. Some of the cell lines have been displaying stable antibody secretions for over 6 months.     

Study on serum neopterin concentration in hemophiliacs with anti-human immunodeficiency-virus type I antibody

The present study was undertaken to discuss whether measurement of neopterin (NP) released into blood from monocytes/macrophage following activation of lymphocytes were useful tool to predict development of AIDS after HIV-1 infection. The subjects used for this study were eighty one cases of hemophilia, of whom 47 cases were HIV-1 antibody tested positive. Serum NP concentration (15.0 +/- 13.8 nmol/l) in anti-HIV-1 antibody-positive group was higher than in-negative group (5.7 +/- 3.3 nmol/l) (p less than 0.05), in which there was no case whose serum NP level amounted to more than 20 nmol/l. In anti-HIV-1 antibody-positive group, in which CD4/CD8 lymphocyte ratio was less than 0.4, serum NP level was significantly higher than in the group whose lymphocyte ratio was more than 0.5 (p less than 0.05). This result represents that there is a reverse correlation of NP concentration with the developing level of immunodeficiency. Furthermore, in eight cases who developed AIDS, serum NP levels turned to increase from several months or earlier until in all cases the levels were more than 30 nmol/l. In three cases of five who were dead, serum NP concentration had decreased to death since several months through one year. These findings reveal that measurement of serum NP concentration is correlated with clinical outcome after HIV-1 infection and it is useful as the marker for prediction of AIDS development. Also these findings represent that a parallel application of serum NP assay to CD4 lymphocyte counting, detection of anti-HIV-1 antibody, IgA, beta 2-microglobulin assays can predict the outcome of the HIV-1 infection more precisely.     

Electrophysiological studies of intermittent claudication in lumbar stenosis

To clarify the pathophysiology of intermittent claudication in 37 patients with lumbar spinal stenosis, neural function was evaluated by examining somatosensory evoked potentials (stress-SEPs), and nerve action potentials (stress-NAPs) before and after walking stress. It was shown preoperatively that the stress-SEPs became abnormal immediately after walking in 31 of 37 patients. In seven of nine operated patients, the assessment clearly shows that SEPs had reverted to normal after surgery. The present method is noninvasive, simple in technique, painless, and safe, a procedure therefore that is useful as the initial step in the diagnosis and treatment of patients with lumbar canal stenosis. It also may help to differentiate neurogenic from vascular intermittent claudication.     

Inferior vena cava thrombus after retroperitoneal lymphadenectomy for testicular tumor

A rare case of a thrombus in the inferior vena cava (IVC) after retroperitoneal lymphadenectomy for a testicular tumor is reported. A computed tomograph performed after the operation incidentally showed a filling defect in the IVC. However, it was impossible to decide whether the defect was due to an ordinary or a neoplastic thrombus. For this reason, a thrombectomy was performed, and postoperatively it was diagnosed as an ordinary thrombus. The cause of thrombi found only in the IVC is reviewed and the indication for thrombectomy is discussed.     

Malfunction of arterial sarcoplasmic reticulum leading to faster and greater contraction induced by high-potassium depolarization in young spontaneously hypertensive rats.

The contribution of sarcoplasmic reticulum was studied with regard to the increase in arterial contraction induced by a high-potassium depolarization in spontaneously hypertensive rats (SHR). The 20 mmol/l potassium-induced contraction of femoral arteries was faster and greater in 6-week-old SHR than in age-matched normotensive Wistar-Kyoto (WKY) rats. Relaxation after washing the arteries with a Krebs solution was slower in SHR than in WKY rats. When the sarcoplasmic reticulum of SHR arteries had been depleted of calcium by caffeine in a calcium-free solution, the rate of high-potassium-induced contraction of the calcium-depleted SHR arteries was slowed, the same result as that with non-calcium-depleted WKY arteries. In ryanodine-treated arteries, the rate and magnitude of high-potassium-induced contraction were enhanced slightly in SHR and greatly in WKY rats, resulting in no final difference between SHR and WKY rats. Ryanodine slowed the relaxation rate in WKY rats but not in SHR. These results suggest that the diminution in ability of sarcoplasmic reticulum to sequester calcium may be responsible for the faster rate and greater magnitude of high-potassium-induced contraction with the slower relaxation in SHR arteries. We postulated that genetic malfunction of sarcoplasmic reticulum causes the increased contraction of arterial smooth muscle leading to the enhanced vasoconstriction and elevated blood pressure in SHR.     

The relation between bronchial infiltration of eosinophils and bronchial hyperresponsiveness in two cases of eosinophilic pneumonia]

We evaluated the bronchial hyperresponsiveness to methacholine in the two cases of eosinophilic pneumonia with infiltration of eosinophils into bronchial mucosa. Bronchial responsiveness was not increased in either case in spite of marked infiltration of eosinophils into the bronchial mucosa and submucosa. Hypodense eosinophils are reported in the sputum of patients with bronchial asthma. This suggests that infiltration of activated eosinophils into the bronchial mucosa is an essential factor in bronchial hyperresponsiveness.     

EFFECTIVENESS OF CYTODIAGNOSIS WITH PANCREATIC DUCT LAVAGE FLUID FOR PANCREATIC DUCTAL CARCINOMA: NEW SAMPLING TECHNIQUE

Background: Pancreatic carcinoma is one of the most lethal cancers. Because pancreatic carcinoma is still very difficult to diagnose in its early stage, many of these patients will be considered unsuitable for surgery. If a cytological diagnosis is obtained at initial endoscopic retrograde cholangiopancreatography (ERCP), suitable treatment will be initiated without delay. Methods: To increase the number of exfoliated cells from the pancreatic duct, we devised a new technique, pancreatic duct lavage fluid (PDLF), following bronchoalveolar lavage fluid. The present paper reports the effectiveness of cytological examination using PDLF in the diagnosis of pancreatic carcinoma. We examined 18 pancreatic carcinoma cases. After the endoscopic retrograde pancreatography (ERP), PDLF was collected from a double‐lumen catheter inserted into the main pancreatic duct. Saline injected from the lumen for the injection, and PDLF was aspirated from the other lumen for the guidewire at the same time. The cytological examination was performed using PDLF. Results: Exfoliated cells were more frequently found in PDLF from all patients. In 15 cases (83%), cytological examination of PDLF revealed positive cytological results as the diagnosis of pancreatic carcinoma. Conclusion: Cytological examination using PDLF has a high sensitivity for detection of pancreatic carcinoma. The new examination, PDLF, is simple, safe and effective, so we expect PDLF to become widely popular.