Laser Structured Dental Zirconium for Soft Tissue Cell Occupation—Importance of Wettability Modulation

Various approaches are being pursued to physico-chemically modify the zirconia neck region of dental implants to improve the integration into the surrounding soft tissue. In this study, polished zirconia discs were laser microstructured with periodic cavities and convex waves. These zirconia samples were additionally activated by argon plasma using the kINPen^®09. The surface topography was characterized by scanning electron microscopy and the surface wettability by water contact angle. The in vitro study with human gingival fibroblasts (HGF-1) was focused on cell spreading, morphology, and actin cytoskeleton organization within the first 24 h. The laser-induced microstructures were originally hydrophobic (e.g., 60 µm cavities 138.4°), but after argon plasma activation, the surfaces switched to the hydrophilic state (60 µm cavities 13.7°). HGF-1 cells adhered flatly on the polished zirconia. Spreading is hampered on cavity structures, and cells avoid the holes. However, cells on laser-induced waves spread well. Interestingly, argon plasma activation for only 1 min promoted adhesion and spreading of HGF-1 cells even after 2 h cultivation. The cells crawl and grow into the depth of the cavities. Thus, a combination of both laser microstructuring and argon plasma activation of zirconia seems to be optimal for a strong gingival cell attachment.     

Therapeutic and prophylactic treatment of skin burns with several calmodulin antagonists

1. Several calmodulin antagonists abolished the decrease in ATP level and in the activities of 6-phosphogluconate dehydrogenase and mitochondrial and soluble hexokinase, induced by burns in the rat skin. 2. These antagonists had also a protective action on the blood capillaries and erythrocyte membrane, as judged by the electron microscopic appearance, as well as the abolishment of hemoglobin increase and burn edema. 3. Of all the compounds investigated here, the most effective were trifluoperazine and thioridazine, which are also known as the more potent calmodulin antagonists. 4. The present experiments suggest that calmodulin antagonists may be effective drugs in treatment of burns, having both therapeutic and prophylactic action.     

Control of blast cell proliferation and differentiation in acute myelogenous leukemia by soluble polypeptide growth factors

Proliferation of acute myelogenous leukemia (AML) derived blast cells requires the presence in culture of one or more growth factors. In the majority of cases Interleukin-3 (IL-3) and granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulate clonogenicity of AML blasts, which can be synergised by Interleukin-6 (IL-6), Interleukin-1 (IL-1) and granulocyte colony-stimulating factor (G-CSF). In contrast, macrophage colony-stimulating factor (M-CSF) favors deterministic divisions. A substantial part of AML samples have clonogenic cells which, however, proliferate autonomously in vitro. The production by leukemic cells of a variety of growth or synergizing factors including GM-CSF, G-CSF, IL-1, IL-6, and Tumor Necrosis Factor (TNF) has been demonstrated and a fraction of cases will use these molecules to support clonogenic growth in an autocrine or paracrine fashion. However, unlike the situation with retrovirus-induced murine or avian leukemias, the role of production of CSFs and other cytokines by human leukemic cells in the transformational process remains uncertain.     

Laryngeal papillomas: classification and course

Seventy-one cases of laryngeal papillomas have been reviewed. Based on differences in age at presentation, female: male ratio and multiple versus solitary papillomas, the cases were classified into 4 groups: multiple juvenile papillomas, solitary juvenile papillomas, multiple and solitary adult papillomas. The clinical course in the groups is described. The authors do not support the common opinion that juvenile papillomas are influenced by puberty.     

Joint space narrowing and relationship with symptoms and signs in adults consulting for hip pain in primary care

OBJECTIVE: To study whether clinical symptoms and signs can predict radiological osteoarthritis (OA) of the hip in primary care patients with hip pain. METHODS: Consecutive patients (n = 220) aged 50 years or older consulting the general practitioner for hip pain and referred for radiological investigation underwent a standardized history, radiological, laboratory, and physical examination. Radiological OA was confirmed with joint space < or = 2.5 mm. Additionally, a more stringent definition was used (< or = 1.5 mm). The relationship between radiological OA and possible clinical symptoms/signs of OA was tested. Combinations of clinical symptoms/signs that had shown an independent relationship with radiological OA in multivariate analyses were tested for their predictive value. RESULTS: Radiological OA (joint space < or = 2.5 mm) of the (more) symptomatic hip was present in 35.5% of the study population and more severe OA (joint space < or = 1.5 mm) in 11.4%. Presence of 4 specific symptoms/signs from history and examination showed a positive predictive value (PPV) of 73% (specificity 91%, sensitivity 45%) for radiological OA. When 5 specific symptoms/signs were present, the PPV for the more severe radiological OA was 82% (specificity 98%, sensitivity 72%), and when 6 or 7 specific symptoms/signs were present the PPV was 100% (specificity 100%, sensitivity 40% and 8%, respectively). Negative predictive values were high for almost all combinations. CONCLUSION: In primary care patients with hip pain, clinical symptoms and signs can to a moderate extent predict radiological OA and to a large extent more severe radiological OA.     

Effects of alcohol and saccharin deprivations on concurrent ethanol and saccharin operant self-administration by alcohol-preferring (P) rats

Consumption of sweet solutions has been associated with a reduction in withdrawal symptoms and alcohol craving in humans. The objective of the present study was to determine the effects of ethanol and saccharin (SACC) deprivations on operant oral self-administration. Alcohol-preferring (P) rats were allowed to lever press concurrently self-administer ethanol (15% vol/vol) and SACC (0.0125% g/vol) for 8 weeks. Rats were then maintained on daily operant access (nondeprived), deprived of both fluids (2 weeks), deprived of SACC and given 2 ml of ethanol daily, or deprived of ethanol and given 2 ml of SACC daily. All groups were then given 2 weeks of daily operant access to ethanol and SACC, followed by an identical second deprivation period. P rats responded more for ethanol than SACC. All deprived groups increased responding on the ethanol lever, but not on the SACC lever. Daily consumption of 2 ml ethanol decreased the duration of the alcohol deprivation effect (ADE). Home cage access to 2 ml of SACC also decreased the ADE but to a lesser extent than access to ethanol. A second deprivation period further increased and prolonged the expression of an ADE. These results show ethanol is a more salient reinforcer than SACC. With concurrent access to ethanol and SACC, P rats do not display a saccharin deprivation effect. Depriving P rats of both ethanol and SACC had the most pronounced effect on the magnitude and duration of the ADE, suggesting that there may be some interactions between ethanol and SACC in their CNS reinforcing effects.