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Docetaxel, a promising novel chemotherapeutic agent in advanced breast cancer. Anticancer Res 2000; 20:3663-8. [PMID: 11268436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
UNLABELLED Clinical practice in chemotherapy of breast cancer is undergoing changes. This study investigated the efficacy and toxicity of docetaxel, a novel chemotherapeutic agent in metastatic breast cancer. Focus was on the effect of the cumulative dose of previous anthracycline treatment on response rate, toxicity and survival in our own patients; published data were reviewed. PATIENTS AND METHODS Thirty-one women, (median age 52 years, range 40-65) treated for metastatic breast cancer with docetaxel were included. RESULTS The overall response rate was 48%, with 3 complete and 11 partial responses (95% CI 29-66). The duration of response was 7 months (range 2 to 16 months), the median overall survival after docetaxel 13.7 months for responding patients, 14.3 months in no-change patients and 6.5 months in patients with progressive disease. The mean cumulative anthracycline dose prior to docetaxel was 860 mg (range 200-1760 mg); in the case of responders, the previous cumulative total epirubicin doses were 200-1575 mg (median 766 mg.). Total dose or schedule of previous epirubicin treatment had no impact on docetaxel response rate, toxicity or survival. The response seen in this study is within the published range (24 to 60%) observed for docetaxel in anthracycline-treated patients. CONCLUSION We conclude that docetaxel is active in metastatic breast cancer even as third- line treatment. Previous treatment with, or response to, epirubicin does not influence the response to docetaxel and this promising new drug is currently being tested for adjuvant use in breast cancer.
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Effect of three days starvation on the phagocytic activity of rat peritoneal macrophages. Acta Haematol 2000; 100:17-21. [PMID: 9691141 DOI: 10.1159/000040856] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To examine the effect of starvation on the phagocytic activity of rat peritoneal macrophages, 8 animals were kept for 3 days on water supply only. The cells showed an increased capacity for superoxide anion production and a marked decrease in their ability to engulf latex particles. The corticosterone level of the fasting animals was markedly increased, an observation suggesting that the alteration of macrophage function could be hormonally mediated. The findings in the present study indicate that the decreased phagocytic capacity of peritoneal macrophages following starvation may be one of the factors responsible for the increased susceptibility to infections in malnourished individuals.
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Ultrastructure and phagocytic activity of rat peritoneal macrophages exposed to low temperatures in vitro. Cryobiology 2000; 41:66-71. [PMID: 11017763 DOI: 10.1006/cryo.2000.2267] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Hypothermia affects various components of the immune system, leading to impaired immune resistance. To examine the in vitro effect of low temperature on the ultrastructure and phagocytic function of rat peritoneal macrophages, cells were incubated at 4, 10, 24, and 37 degrees C for 60 min. Subsequently, their ultrastructure and capacity to engulf latex particles and generate superoxide anions were evaluated. The results showed a close inverse relationship between incubation temperature and ultrastructural changes, i.e., the lower the temperature, the higher the number of altered cells. In addition, at lower temperatures the number of cells capable of phagocytosis was reduced; the cells engulfed fewer particles per cell and generated less superoxide anions. These findings may be relevant for explaining the increased susceptibility to bacterial infections under hypothermic conditions.
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Abstract
The importance of cytokines as mediators in numerous physiologic and pathologic processes became apparent in the early seventies. In a relatively short period of time the number of characterized and functionally defined interleukins increased rapidly. Concomitantly, the understanding of their role in various important reactions in different systems of the organism in general, and in the interaction between the immune, central nervous and neuroendocrine systems in particular increased. IL-3 is one of the cytokines of great significance for hematopoiesis. In addition, it was shown that interleukin-3 (IL-3) participates in the response of the organism to various types of stress. Surprisingly enough, the reports on its production and activation during or following stress are rather scarce. Therefore, the purpose of this review is to try and compile the information on IL-3 and its role in different types of stress, and also to contribute our own modest experience on the subject.
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Effects of antioxidants apocynin and the natural water-soluble antioxidant from spinach on cellular damage induced by lipopolysaccaride in the rat. Toxicol Pathol 2000; 28:580-7. [PMID: 10930046 DOI: 10.1177/019262330002800412] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Oxidative damage plays a key role in septic shock induced by the endotoxin lipopolysaccaride (LPS) by enhancing the formation of reactive oxygen species such as superoxide anion radicals, peroxides, and their secondary product, malondialdehyde, especially in the liver. In this study, histopathologic changes in several organs were compared among groups of male Wistar rats that had been injected with LPS following prophylactic pretreatment with either of 2 antioxidants, a group that had been injected with LPS without pretreatment with antioxidants, an untreated control group, and groups that had been injected with either of the 2 antioxidants only. The antioxidants used were a water-soluble natural antioxidant from spinach (NAO) and the NADPH oxidase inhibitor apocynin. Hematoxylin-and-eosin-stained slides were prepared, and lesions were semiquantitatively scored. Exposure to LPS alone was associated with multifocal hepatocellular necrosis and acute inflammation, thymic and splenic lymphoid necrosis, ocular retinal hemorrhage and acute endophthalmitis, adrenal medullary vacuolation and necrosis and acute inflammation, and decreased adrenal cortical cytoplasmic vacuolation (consistent with depletion of steroidal hormone contents). Results indicated that pretreatment with both antioxidants for 8 days reduced, in some organs, the necrotic and inflammatory changes associated with the LPS challenge. These findings suggest a potential therapeutic application for these antioxidants in clinical sepsis.
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Effect of diazepam on the immune response of rats exposed to acute and chronic swim stress. Biomed Pharmacother 2000; 54:311-5. [PMID: 10989964 DOI: 10.1016/s0753-3322(00)80053-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
To examine the effect of the anti-stress agent diazepam on the immune response, rats were exposed either to acute swim stress, i.e., swimming once only for 30 minutes (non-trained swimmers), or to chronic stress with gradual progressive training for 6 weeks (trained swimmers). Both groups of animals were divided into subgroups treated before swimming with and without diazepam, 1 mg/kg, administered i.m. The phagocytic capacity and superoxide anion generation of the peritoneal macrophages was examined. In addition, the proliferative response of the splenic cells (splenocytes) to concanavalin A (Con A) and phytohemagglutinin (PHA), as well as the serum corticosterone levels were investigated. Diazepam abolished increased superoxide anion production in both non-trained and trained swimmers. In non-trained swimmers, the number of latex particles internalized by each cell was decreased and further reduced by the drug. In trained rats treated with diazepam, the percentage of phagocytosing cells remained reduced compared to controls, whereas the drug prevented a decrease in the engulfing capacity of individual cells. Diazepam lowered the suppressed proliferative response of the splenocytes to PHA found in non-trained swimmers. It is concluded that diazepam modifies the immune response of rats exposed to acute and chronic swim stress.
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Effect of training on the phagocytic capacity of peritoneal macrophages from rats exposed to swim stress. Acta Haematol 2000; 102:180-4. [PMID: 10725759 DOI: 10.1159/000041011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Since strenuous effort may affect the immune system, a study was designed to examine the impact of the progressive training of rats exposed to swim stress. Rats (trained swimmers) were forced to swim daily in a water bath for progressively longer periods. At the end of the study, which continued for a total of 6 weeks, the superoxide anion generation and phagocytic capacity of peritoneal macrophages, the mitogen response of splenic cells (splenocytes) and the serum corticosterone level were examined. The results, compared to those of animals taken in and out of their cages (nonswimmers), showed an increase in superoxide anion generation, as well as a decrease in both the percentage of phagocytosing cells and the number of particles internalized by each individual cell. In trained swimmers, the mitogen response to phytohemagglutinin and concanavalin A (Con A), as well as the corticosterone level, did not change significantly from those of nonswimmers. A third group of animals were forced to swim once only for 30 min, until the appearance of signs of marked fatigue (acute swimmers). Their peritoneal macrophages showed an increased superoxide anion generation and a significantly decreased response to Con A compared to those of the nonswimmers. The serum corticosterone level in acute swimmers was found to be increased compared to that of an additional group of animals kept at complete rest. The findings indicate that the progressive training of rats exposed to swim stress does not prevent alterations in certain immune responses, a fact that should be considered by intensive exercisers.
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Docetaxel and autonomic cardiovascular control in anthracycline treated breast cancer patients. Anticancer Res 2000; 20:2045-8. [PMID: 10928149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
BACKGROUND Taxoids are new chemotherapeutic agents effective in the treatment of breast cancer. Paclitaxel treatment has been reported to cause some cardiac side effects and both paclitaxel and docetaxel to cause mild, mainly sensory, peripheral neuropathy. Autonomic function tests are sensitive measures of autonomic neuropathy and cardiac regulation. The purpose of this study was to find out whether docetaxel changes neural cardiovascular regulation in breast cancer patients previously treated with anthracyclines. PATIENTS AND METHODS Nine women treated for metastatic breast cancer with docetaxel were studied prior to the docetaxel treatment and after the third or fourth course. Autonomic cardiovascular function tests were performed and heart rate and blood pressure variability were assessed with power spectrum analysis. RESULTS Heart rate variability or the heart rate responses to the autonomic function tests did not change after docetaxel treatment. The blood pressure response to standing was enhanced and systolic blood pressure variability decreased after three to four cycles of docetaxel. CONCLUSIONS Docetaxel treatment did not deteriorate vagal cardiac control in breast cancer patients after exposure to epirubicin. The observed changes in blood pressure responses suggest that docetaxel changes sympathetic vascular control. However, these changes seem to be related to altered cardiovascular homeostasis rather than peripheral sympathetic neuropathy.
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Abstract
After myocardial ischemia, circulating levels of the mitogen endothelin-1 (ET-1) increase. The effects of ET-1 on cardiac fibroblasts are poorly characterized. Therefore we examined the influence of ET-1 on cardiac fibroblast proliferation with a view to elucidating the signal transduction mechanisms underlying this effect. ET-1 (10 n m) stimulated [(3)H]thymidine incorporation and cell proliferation in cultured neonatal rat cardiac fibroblasts, consistent with its activity as a mitogen. We examined the role of protein kinase C (PKC) on this function. Inhibition of PKC activation with either chelerythrine (1 microm) or staurosporine (1 n m) attenuated ET-1-induced increases in DNA synthesis and cell number. Downregulation of PKC by chronic pretreatment with 10 n m phorbol 12-myristate 13-acetate (PMA) also prevented ET-1-induced mitogenesis. In contrast to previous reports that cardiac fibroblast proliferation stimulated by angiotensin II acts independently of PKC, the ET-1 mediated mitogenic effect requires activation of PKC in these cells. Findings in adult rat cardiac fibroblasts were identical. In addition, we noted that concurrent treatment with the pro-inflammatory cytokine interleukin 1 beta which, like ET-1, is released after myocardial ischemia, attenuated the ET-1-induced increases in DNA synthesis and cell number. This effect was not mediated through a nitric oxide synthase pathway.
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Hypothermia affects the phagocytic activity of rat peritoneal macrophages. ACTA PHYSIOLOGICA SCANDINAVICA 2000; 168:431-6. [PMID: 10712581 DOI: 10.1046/j.1365-201x.2000.00686.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To examine the effect of hypothermia on the phagocytic capacity of rat peritoneal macrophages for latex particles, male Wistar rats were exposed to 4 degrees C for 8 and 72 h. While the shorter exposure to cold did not affect body temperature and macrophage function, animals exposed to 4 degrees C for 72 h showed a mean decrease of their body temperature by 1.5 degrees C. The superoxide anion production was significantly increased whereas the number of phagocytic cells decreased. In addition, the mean number of latex particles engulfed by each individual cell was lower than that of controls. Peripheral blood mononuclear cells (PBMC) of these animals showed lower mitogen response to phytohaemagglutinin (PHA), while that for concanavalin A (Con-A) remained unchanged. Peritoneal macrophages exposed in vitro to 24 degrees C for 60 min showed a decreased phagocytic capacity in comparison with macrophages kept at 37 degrees C, an observation suggesting the development of an indigenous cell defect for phagocytosis at lower temperatures. On the other hand, the effect of additional humoral factor(s) on macrophage activity, such as an increase in serum level of catecholamines and corticosterone, cannot be excluded. The results of the study may contribute to understanding the predisposition to infections during exposure to cold.
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Abstract
Dental treatment usually involves a wide range of materials which continue to grow in number and complexity. During the last decade there has been an increasing demand for safety evaluation and control of dental materials. Since it is the members of the dental staff who handle the materials in their most reactive states they constitute the main risk category. Bearing this in mind reported side-effects in both patients and dental personnel in Scandinavia are presented. Data from the only two existing national registers for side-effects of dental materials, i.e. those in Norway and Sweden, are thus elucidated. Furthermore, recent mainly Scandinavian publications dealing with the side-effects of dental materials are presented. It can be concluded that a national register on the side-effects of dental materials, apart from revealing information regarding their frequency and nature, may detect changes in the profiles of adverse reactions and also serve as a tool for the post-marketing surveillance of dental materials.
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Platelet-derived growth factor (PDGF)-induced activation of signal transducer and activator of transcription (Stat) 5 is mediated by PDGF beta-receptor and is not dependent on c-src, fyn, jak1 or jak2 kinases. Biochem J 2000; 345 Pt 3:759-66. [PMID: 10642538 PMCID: PMC1220814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
Several growth factors activate signal transducers and activators of transcription (Stats) but the mechanism of Stat activation in receptor tyrosine kinase signalling has remained elusive. In the present study we have analysed the roles of different platelet-derived growth factor (PDGF)-induced tyrosine kinases in the activation of Stat5. Co-expression experiments in insect and mammalian cells demonstrated that both PDGF beta-receptor (PDGF beta-R) and Jak1, but not c-Src, induced the activation of Stat5. Furthermore, immune-complex-purified PDGF beta-R was able to phosphorylate Stat5 directly. The role of the cytoplasmic tyrosine kinases in the PDGF-induced activation of Stat5 was further investigated by overexpressing kinase-negative (KN) and wild-type Jak and c-Src kinases. Jak1-KN or Jak2-KN had no effect but both Src-KN and wild-type c-Src similarly decreased the PDGF-beta-R-induced activation of Stat5. The activation of both Src and Stat5 is dependent on the same tyrosine residues Tyr(579) and Tyr(581) in PDGF beta-R; thus the observed inhibition by Src might result from competition for binding of Stat5 to the receptor. Finally, fibroblasts derived from Src(-/-) and Fyn(-/-) mice showed normal pattern of PDGF-induced tyrosine phosphorylation of Stat5. Taken together, these results indicate that Stat5 is a direct substrate for PDGF beta-R and that the activation does not require Jak1, Jak2, c-Src or Fyn tyrosine kinases.
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Abstract
Photon irradiation of the abdomen may be accompanied by complications due to a decrease in the immune defense of the recipient. Since peritoneal macrophages are an important component of the immune system, we examined the phagocytic activity and oxygen superoxide anion generation by peritoneal macrophages from rats 2 and 4 weeks after abdominal irradiation with 6 MV photons applying a single dose of 2 Gy. Two and 4 weeks after irradiation, peritoneal macrophages were harvested and their capacity to engulf latex particles and to produce oxygen superoxide anions was determined. Non-irradiated rats, treated identically otherwise, served as controls. Two weeks after irradiation the phagocytic capacity and oxygen superoxide anion generation decreased by 61 and 70%, respectively, compared with controls. This tendency persisted after 4 weeks post irradiation, the decrease in both functions being 50 and 74%, respectively. It is suggested that the altered function of peritoneal macrophages following irradiation may further compromise the immune defense in patients receiving abdominal radiotherapy.
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Abstract
In the present study the effect of LPS on biochemical systems involved in radical formation and scavenging processes in tissues from rabbit (LPS-sensitive) and rat (LPS-resistant) was investigated. The results obtained show a significant enhancement in the endogenous antioxidative enzyme system in rats as a result of LPS injection. In rats, 24 h after LPS injection, glutathione peroxidase (G-POX) and superoxide dismutase (SOD) activities were increased by 60% and 120%, respectively, compared to the control. However, in rabbits the increase in these activities was relatively mild. Moreover, NADPH-oxidase activity, which produces superoxide radical, was increased about twofold in rabbit, 15 h following LPS injection. In rats, injection of LPS did not result in any significant changes in the activity of this enzyme. In rats, a decrease in malonaldehyde (MDA) levels appeared after injection of LPS, while in contradistinction, the peroxidative levels of lipids in the rabbit's liver were increased about 3-fold. Injection of D-galactosamine (Gal-N) in combination with LPS significantly increased the sensitivity of rats to LPS characterized by a significant increase in NADPH-oxidase activity. This study indicates that one possible mechanism (among others) that may explain the relative sensitivity of rabbits compared to rat, may be related to the increase in the production of reactive oxygen substances (ROS) which is not accompanied by a concomitant increase of the protective antioxidative enzymes. Furthermore, the relative resistance of the rat was found to be related to an increase in the activity of the protective antioxidative systems following administration of LPS.
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Huge coronary artery aneurysms presenting as mediastinal masses. THE ISRAEL MEDICAL ASSOCIATION JOURNAL : IMAJ 1999; 1:53-4. [PMID: 11370125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
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Effect of a garlic derivative (alliin) on peripheral blood cell immune responses. INTERNATIONAL JOURNAL OF IMMUNOPHARMACOLOGY 1999; 21:589-97. [PMID: 10501628 DOI: 10.1016/s0192-0561(99)00038-7] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The in vitro effect of the garlic derivative alliin, on the mitogen induced peripheral blood mononuclear cell (PBMC) proliferation and cytokine production was examined. In addition, its effect on the engulfing capacity of phagocyting cells was evaluated. The results showed an increase in pokeweed mitogen (PWM) induced cell proliferation, IL-1beta and TNF-alpha production, as well as in the engulfing capacity of both percentage of phagocyting cells and number of latex particles phagocytized by each individual cell. The Con-A induced cell proliferation and IL-6 production decreased following incubation with alliin, whereas PHA-induced cell proliferation, IL-2 and superoxide anion generation remained unchanged. It is concluded that alliin in vitro exerts an immunomodulatory effect on certain functions of the peripheral blood cells.
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Abstract
OBJECTIVE To determine the prevalence of hydronephrosis in patients with genital prolapse and evaluate contributing factors. METHODS Retrospective study of the records of 189 patients with pelvic organ prolapse who underwent preoperative renal imaging studies. RESULTS Of the 189 patients 31 (17.4%) had hydronephrosis; in 20 (10.6%) patients the hydronephrosis was mild, in 7 (3.7%) it was moderate and in 4 (2.7%) it was severe. The patients with hydronephrosis were older (mean age 68+/-9.5 SD vs. 60.5+/-10.8 SD, P<0.001) had a higher creatinine levels (0.84+/-0.4 SD vs. 0.78+/-0.3 SD P<0.005) and had a higher degree of uterine prolapse (mean 2.6+/-0.9 SD vs. 1.1+/-1.2 SD, P<0.005). After adjusting for age and type of prolapse, only patients with uterine prolapse remained significantly more likely to suffer from hydronephrosis (adjusted odds ratio 1.9, 95% CI 1.1, 3.2). CONCLUSION The prevalence of hydronephrosis in patients with genital prolapse is appreciable and is related primarily to degree of uterine prolapse.
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Labor abnormalities as a risk factor for shoulder dystocia. Acta Obstet Gynecol Scand 1999; 78:735-6. [PMID: 10468068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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Abstract
The cost of medical care is constantly increasing. Therefore, ways of saving expenses should be considered. The aim of the present study is to evaluate the possibility than an awareness of the cost of drugs for treatment of hypertension may affect physicians' prescription decisions. A questionnaire containing the clinical data of a young and an elderly imaginary patient with moderate hypertension was given to 30 family physicians and 30 hospital physicians together with a list of appropriate drugs (phase I). This was repeated as phase II except that for this stage the cost of the drugs was brought to the participants' attention. Knowing the cost of the drugs caused a decrease in prescription of the more expensive drugs for the younger patients; of 60% (family physicians) and 87% (hospital physicians). For their elderly patients family physicians preferred the less expensive drugs at both phases. 25% of the hospital doctors changed their preference towards less expensive drugs at phase II. For the younger patient, no correlation was found between the number of years of physicians' practice and the cost of the drugs chosen. For the elderly patient, physicians from both groups preferred less expensive drugs at phase II without any relation to their years of practice. The results of this study indicate that a knowledge of the price of the drugs may affect physicians' prescription decisions, a fact that may result in considerable saving by health providing organizations.
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The Decim system for the production of dental restorations. INTERNATIONAL JOURNAL OF COMPUTERIZED DENTISTRY 1999; 2:197-207. [PMID: 11351484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
The general background to the development of CAD/CAM is presented in short. Specific problems when using this technique for the manufacturing of dental restorations are emphasized, and then the reverse engineering and CAD/CAM process that have been implemented in the Decim (Dentronic AB, Skellefteå, Sweden) system are presented. The system is organized in the following way: 1. The measurement process is encapsulated in a product called Decim Reader. 2. The design functionality is provided by software running on a conventional personal computer. This unit is called Decim Designer. 3. The CAM calculation is done by a dedicated personal computer, the Decim Calculator, that does not require any user interaction. 4. The actual manufacturing of the restorations is performed in the Decim Producer that works with a grinding technique. These components communicate via a local computer network or, when a distributed solution is desired, via internet. The Decim System is presently used for the production of dental ceramic restorations, and it is the only system which can be used for manufacturing inlays of yttria-stabilized zirconia. This ceramic material is CE-approved under the brand name Denzir (Dentronic AB, Skellefteå, Sweden). Due to its favorable mechanical properties, it may be an alternative to dental amalgam, and is therefore of topical interest in dentistry. The use of computer-based techniques for manufacturing dental restorations is briefly outlined and commented on.
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Abstract
Adenosine protects the ischemic myocardium by coronary vasodilation and the depression of heart rate and contractility, improving myocardial energy balance. Adenosine effects on the myocardium are mediated predominantly by the type A1 receptors. Atrial natriuretic peptide (ANP), a vasodilator and regulator of blood volume, is secreted from either atrial or ventricular myocytes in response to cellular distention. In vivo, adenosine infusion has been shown to induce a rapid increase in plasma ANP, independent of blood pressure. We examined the possibility that adenosine enhances ANP-gene expression in cardiac myocytes. Administration of adenosine (10 microM) to cultured neonatal rat cardiomyocytes led to a 1.7-fold increase (p = 0.014, n = 9) in the abundance of ANP messenger RNA (mRNA) within 30 min, as measured by Northern blot hybridization. No such increase was obtained when adenosine was coadministered with 8-cyclopentyl-1,3dipropylxanthine (CPX, 10 microM), an adenosine A1-receptor antagonist. Our results point at adenosine as regulator of ANP mRNA level in cardiac myocytes.
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Abstract
To determine the phagocytic function of the peripheral blood polymorphonuclears from patients with treated and untreated Parkinson's disease (PD), these cells were incubated with latex particles and the number of phagocytes, as well as the number of particles engulfed by each individual cell, were counted. Cells of untreated PD patients were significantly less phagocytotic than those of matched subjects without neurological or immune disorders (24% vs. 45%, P < 0.001). In addition, phagocytes from PD patients engulfed less particles per cell than those of the controls (8.4 +/- 0.7 vs. 16.5 +/- 1.3, P < 0.001). There was no significant difference in both functions in untreated and treated PD. The results indicate that in addition to the known immune alterations in patients with PD, the ability of their peripheral blood phagocytic cells to engulf latex particles is impaired.
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Docetaxel: standard recommended dose of 100 mg/m(2) is effective but not feasible for some metastatic breast cancer patients heavily pretreated with chemotherapy-A phase II single-center study. J Clin Oncol 1999; 17:1127. [PMID: 10561170 DOI: 10.1200/jco.1999.17.4.1127] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Patients with metastatic breast cancer, especially those with progression after several prior chemotherapy treatments, need efficient chemotherapy. This study investigates the efficacy and toxicity of docetaxel in metastatic breast cancer patients with previous chemotherapy for metastatic disease. PATIENTS AND METHODS Thirty-one women (median age, 52 years; range, 40 to 65 years) treated for metastatic breast cancer with docetaxel were included. Eleven patients had one metastatic site, 10 patients had two, and 10 patients had three or more. The planned dose of docetaxel per course was the standard treatment of 100 mg/m(2) (or 75 mg/m(2) if liver enzyme levels were abnormal) every 3 weeks, given for six or eight cycles. RESULTS The overall response rate was 48% (three complete responses [CR] and 11 partial responses [PR] ), and the median duration of response was 7 months (range, 2 to 16 months). Twenty patients (65%) experienced fatigue, and 27 patients (87%) had alopecia. Fifteen cases (48%) of grade 4 leukopenia were observed. Edema with a weight gain of 2 to 15 kg was seen in 12 patients (39%), and mucositis occurred in 20 patients (65%). Twenty-three patients (74%) interrupted treatment before reaching the planned number of courses, nine patients owing to progression of cancer and 14 owing to toxicity. Dose reduction was required in 18 (61%) of the patients. Only two patients were able to receive the planned eight courses without dose reduction. CONCLUSION Docetaxel is highly active in metastatic breast cancer, even as a third-line treatment, and can be considered as an efficient standard option in second-line treatment. The standard recommended dose level of 100 mg/m(2) is not feasible in heavily pretreated patients; therefore, for such patients, an initial dose level not exceeding 75 mg/m(2) is recommended.
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IL-1 beta, IL-2, IL-6 and TNF-alpha production by peripheral blood mononuclear cells from patients with Parkinson's disease. Biomed Pharmacother 1999; 53:141-5. [PMID: 10349502 DOI: 10.1016/s0753-3322(99)80079-1] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The capacity of peripheral blood mononuclear cells (PBMC) from patients with treated Parkinson's disease (PD) to produce interleukin (IL) IL-1 beta IL-2, IL-6, tumor necrosis factor (TNF)-alpha and the proliferative response to mitogens, was compared with that from cells from healthy subjects. The production of IL-2 and the mitogen response were significantly lower in PD patients, whereas the secretion of IL-1 beta, IL-6 and TNF-alpha were significantly enhanced. To evaluate the role of levodopa in creating immunological alterations, PBMC of patients and controls were incubated with concentrations of the drug extrapolated from those used in clinical practice. Levodopa caused an inhibition of mitogen-induced proliferation, stimulation of IL-6 and TNF-alpha production, whereas the secretion of IL-1 beta and IL-2 was not affected. The results of the study provide a further support for the interrelationship between the central nervous and immune system. In addition, the data indicate that the immunological alterations found in PD may be partially attributed to levodopa administration.
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The effect of interferon on mouse myocardial capillaries: an ultrastructural study. Cancer 1999; 85:1375-9. [PMID: 10189145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
BACKGROUND Cardiotoxicity, including ischemia and myocardial infarction, is one of the complications observed after treatment with interferon (IFN). Therefore, the question has been raised whether IFN may cause damage to the small myocardial blood vessels. METHODS In this study, 400 U of IFN-alpha-2b per g of body weight were injected intraperitoneally into 2 groups of C57 B1 mice, 5 days a week for 3 and 5 months, respectively. Thin sections of the myocardium were examined with a transmission electron microscope and the ultrastructure of the capillaries was compared with that of control animals. RESULTS The results showed a statistically significant increase in the thickness of the endothelial processes of the myocardial capillary walls in the mice treated with IFN, with a subsequent decrease in the size of the capillary lumen. The entire capillary area was not affected. CONCLUSIONS These findings may serve as an additional explanation for the cardiac complications observed in patients treated with IFN.
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Abstract
The corrosion of cast or milled ASTM Grade II CP titanium with different surface conditions was studied by potentiodynamic anodic polarization and immersion testing. Specimens were fabricated using three dental titanium casting systems and from machined titanium. Three surface conditions were tested: (1) sandblasted with surface reaction layers remaining; (2) polished surface without surface reaction layers; and (3) sandblasted surface without surface reaction layers. An acidic saline solution (0.1 M lactic acid/0.1 M NaC1 [pH = 2]) and an artificial saliva were used as the corrosion media. Anodic polarization was performed starting at 50 mV below the rest potential and terminating at +2250 mV vs Ag/AgCl. Two surface conditions (sandblasted with the surface reaction layers and polished without such layers) were examined in the immersion test. Specimens were immersed in the corrosion media at 37 degrees C for six months. The recovered solution was analyzed by an atomic absorption spectrophotometer for titanium dissolution. A distinctive passive region on the polarization diagram, ranging from approximately 0 to approximately +1300 mV, was observed for all specimens in both media. Great similarity was observed for all the sandblasted specimens which had larger primary passive current densities and passive regions compared to the polished ones. A current density peak at approximately +1600 mV seen for all the specimens with sandblasted surfaces was less well defined for the polished specimens. Immersion testing in the acidic saline solution revealed no significant differences among the polished specimens. A significant increase (P < 0.05) in titanium dissolution was found for the sandblasted specimens with surface reaction layers remaining on the surfaces made with phosphate-bonded SiO2/Al2O3 investment compared to the polished ones. Significant differences were also found between sandblasted specimens with the surface reaction layers resulting from different investment materials and different casting methods. Measurable amounts of titanium were not found for all specimens in the artificial saliva after six months. It is evident that the corrosion behavior of cast CP titanium is similar to that of machined titanium. The surface roughness appears to be a more prominent factor than do the surface reaction layers on the polarization behavior of the CP titanium under the present experimental conditions. Surface roughness and the presence of the surface reaction layers both affect the dissolution of titanium.
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128
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Abstract
To elucidate the effect of sodium thiopentone anesthesia on the function of phagocytic cells, albino rats were anesthetized with 60 mg/kg. of sodium thiopentone. After 90 min., peritoneal macrophages were harvested and their capacity for superoxide anion generation was detected. Following anesthesia for 90 min. latex particles were injected intraperitoneally, and after additional 30 min. the macrophages were derived, embedded in agar and the number of cells engaged in phagocytosis, as well as the number of latex particles engulfed by each individual cell were counted in semi-thick sections. Macrophages of anesthetized animals showed a statistically significant decrease of both superoxide anion generation and mean number of phagocytic cells, and engulfed fewer particles than those of the controls. Similar results were obtained following incubation of the cells with sodium thiopentone in vitro. The serum corticosterone level in anesthetized rats was significantly higher than that of the control animals. The results indicate that impaired phagocytosis following anesthesia induced by sodium thiopentone, in addition to alterations of the immune system caused by surgical trauma, may be one of the reasons for increased susceptibility to infections of surgical patients during the postoperative period.
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129
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Letter to the Editor. J Dent Res 1998. [DOI: 10.1177/00220345980770040301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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130
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In vitro and in vivo effects of beta-carotene on rat epidermal lipoxygenases. INT J VITAM NUTR RES 1998; 67:407-14. [PMID: 9433673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The in vitro and in vivo interaction between beta-carotene (BC) and lipoxygenase (LOX) was studied in rat skin. Significant in vitro inhibitory effects of BC on epidermal LOX activity were observed with both linoleic acid or arachidonic acid as substrate. Lineweaver-Burk plots for the inhibition of epidermal purified LOX indicated mixed competitive/non-competitive inhibition. In vivo effects of BC were examined in an ultraviolet A (UVA) irradiation model. Following UVA irradiation (200 Kjoule/m2) significant increases in LOX activity and malondialdehyde (MDA) values were found, whereas catalase activity was significantly decreased. Topical pretreatment of skin with BC prevented increases in LOX activity and MDA values 4 hr post-irradiation. Catalase activity was not affected by BC treatment. BC was more effective at preventing UVA induced lipid peroxidation at low then at high concentrations. Our present results indicate the protective potential of BC on in vivo UVA induced skin damage by reduction of non-enzymatic and enzymatic lipid peroxidation.
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131
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Ultrastructural observations on the cells of a patient with Fanconi's anemia transforming to acute leukemia. CELL VISION : THE JOURNAL OF ANALYTICAL MORPHOLOGY 1998; 5:28-32. [PMID: 9660722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The ultrastructural findings in the bone marrow and peripheral blood cells of a patient with Fanconi's anemia transforming to acute myelo-monocytic leukemia are presented. They consisted of an unusual large number of nuclear pockets, bridges and appendices observed in the nuclei of the polymorphonuclear cells, monocytes and to a lesser extent in the mature normoblasts. Since the mother and two younger brothers of the propositus were found to have macrocytic anemia and pancytopenia, most probably Fanconi's anemia, their peripheral blood cells were also examined with the electron microscope. The cells of all of them showed similar nuclear alterations, although in lesser quantity. The possibility that these findings are consistent with the diagnosis of Fanconi's anemia, or they herald an evolution of the disease to acute leukemia is considered.
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132
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Abstract
When reading papers concerning studies of corrosion of dental amalgam and its phases by means of polarization curves, one often finds it difficult to understand the reasons for the chemical reactions proposed from the form of the polarization curve. Thermodynamic data represented in the form of log(a[i]/a[ref])-pe diagrams, i.e., the logarithm of the activity of a metal or an alloy with reference to the activity of the corresponding metal ion, as a function of pe (a recalculated form of the potential), make it possible for one to determine which chemical reactions can occur on the specimen surface or in the solution within the potential difference used in the polarization experiment and to decide which of these reactions is the most probable. The hypothesis examined in this study is that a log(a[i]/a[ref])-pe diagram can be used in the interpretation of polarization curves. Potentiodynamic polarization curves and log(a[i]/a[ref])-pe diagrams were compared for the corrosion of Ag, Hg, and gamma 1 with and without Sn. It was found that there was a connection between the polarization curves and the log(a[i]/a[ref])-pe diagrams. From the composition of the specimens and the solution and by means of thermodynamic data, pe values for solid corrosion products and relative concentrations of soluble complexes at these pe values were obtained independently of the polarization curves. A much more reliable value for the nobility of metals and alloys was attained by use of the log(a[i]/a[ref])-pe diagrams than by use of the potential of the starting point of the polarization curves. It was found that pe corresponding to the potential of the starting point of the polarization curves in de-aerated synthetic saliva was obtained about two pe units before pe of the most insoluble solid compound formed on the specimen surface or in the solution.
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133
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Multisensory speech perception of young children with profound hearing loss. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 1997; 40:1135-1150. [PMID: 9328885 DOI: 10.1044/jslhr.4005.1135] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The contribution of a two-channel vibrotactile aid (Trill VTA 2/3, AVR Communications LTD) to the audiovisual perception of speech was evaluated in four young children with profound hearing loss using words and speech pattern contrasts. An intensive, hierarchical, and systematic training program was provided. The results show that the addition of the tactile (T) modality to the auditory and visual (A+V) modalities enhanced speech perception performance significantly on all tests. Specifically, at the end of the training sessions, the tactile supplementation increased word recognition scores in a 44-word, closed-set task by 12 percentage points; detection of consonant in final position by 50 percentage points; detection of sibilant in final position by 30 percentage points; and detection of voicing in final position by 25 percentage points. Significant learning over time was evident for all test materials, in all modalities. As expected, fastest learning (i.e., smallest time constants) was found for the AVT condition. The results of this study provide further evidence that sensory information provided by the tactile modality can enhance speech perception in young children.
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134
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Abstract
OBJECTIVE Depressive episodes among alcohol-dependent men and women are heterogeneous in causation and clinical course. This study tested three hypotheses regarding the rates and clinical characteristics of two potential subtypes of these affective states: those that appear to be substance-induced mood disorders and those that are independent major depressive episodes. METHOD Semistructured, detailed interviews were administered to 2,945 alcohol-dependent subjects as part of the Collaborative Study on the Genetics of Alcoholism. With the use of a time line method for determining the type of mood disorder among probands, relatives, and comparison subjects, individuals with histories of the two types of mood disorders were compared. RESULTS Major depressive episodes with an onset before the development of alcohol dependence or during a subsequent long abstinence period (i.e., independent depressions) were observed in 15.2% of the alcoholics, while 26.4% reported at least one substance-induced depressive episode. According to a logistic regression analysis, the subjects with independent (as compared to substance-induced) major depressive episodes were more likely to be married, Caucasian, and female, to have had experience with fewer drugs and less treatment for alcoholism, to have attempted suicide, and, on the basis of personal interviews with family members, to have a close relative with a major mood disorder. CONCLUSIONS These results support the contention that it is possible to differentiate between what appear to be substance-induced and independent depressive episodes in alcoholics. Such differentiation might be important for establishing prognosis and optimal treatment.
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135
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Abstract
OBJECTIVE To study the impact of the cost of pharmaceuticals on physicians' decisions about drug prescription. DESIGN A simulation protocol for the treatment of two patients, one with mild and the other with a severe form of urinary tract infection (UTI), was designed. Thirty family physicians in outpatient clinics and 30 physicians in the internal medicine wards of a Community Hospital participated in the project. They had to prescribe treatment for the patients twice: at phase I, when the drug cost was unknown, and at phase II, after 2 months, when the price of the drugs was brought to their attention. The physicians selected the medication from a list of drugs commonly used for the treatment of UTIs. RESULTS Analysis of the findings indicates that an awareness of drug costs affects prescription decisions among physicians in hospital wards, whereas family physicians showed a preference for less expensive drugs even before they were informed about drug costs. An extrapolation of the results shows that knowledge about the cost of the drugs usually administered for treatment of UTI, could save at least IS 112,883 ($34,207) a month to Kupat Holim Klalit (KHK) the health insurance institution to which the outpatient clinics and the hospital belong. CONCLUSIONS When economic aspects of healthcare are considered, information on drug costs may be an important factor in physicians' decision-making processes and for saving pharmaceutical expenses.
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136
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Identification of csk tyrosine phosphorylation sites and a tyrosine residue important for kinase domain structure. Biochem J 1997; 322 ( Pt 3):927-35. [PMID: 9148770 PMCID: PMC1218276 DOI: 10.1042/bj3220927] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The lack of a conserved tyrosine autophosphorylation site is a unique feature of the C-terminal Src-kinase, Csk, although this protein tyrosine kinase can be autophosphorylated on tyrosine residues in vitro and in bacteria. Here we show that human Csk is tyrosine phosphorylated in HeLa cells treated with sodium pervanadate. Phosphorylation in vivo occurs mainly at Tyr-184 and in vitro mainly at Tyr-304. A Y304F mutation strongly decreased Csk phosphorylation in vitro, and a Y184F mutation abolished tyrosine phosphorylation in vivo. A catalytically inactive form of Csk was also phosphorylated on Tyr-184 in vivo, suggesting that this is not a site of autophosphorylation. The kinase activity of the Y184F protein was not changed, while the Y304F protein showed one-third of wild-type activity. Three-dimensional modelling of the Csk kinase domain indicated that the Y304F mutation abolishes one of two conserved hydrogen bonds between the upper and the lower lobes in the open conformation of the kinase domain. Phosphopeptide binding studies suggested that phosphorylation of Tyr-184 creates a binding site for low-molecular-mass proteins. Cellular Csk was associated with several phosphoproteins, some of which were interacting with the Csk SH2 domain. Taken together these results indicate that Csk can be phosphorylated in vivo at Tyr-184 by an as yet unknown tyrosine kinase, and that autophosphorylation of Tyr-304 occurs only at abnormally high Csk concentrations in vitro. Furthermore, Tyr-304 is required for the maintenance of the structure of the Csk kinase domain.
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137
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Perception of speech--normal and abnormal. Adv Otorhinolaryngol 1997; 51:93-102. [PMID: 9017078 DOI: 10.1159/000058941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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138
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139
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The tradeoffs of successful simulation. Stud Health Technol Inform 1996; 39:565-71. [PMID: 10168951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
This presentation will discuss the decision process we followed to develop an ultrasound simulator. The development of an advanced technology medical device always requires tradeoffs and compromises between what is desired, and what can be realistically achieved. The medical applications of computer based education are increasingly important to the process of medical education. Product developers will be required to address these concerns. Some tradeoffs result from technical, scientific, and engineering factors; while others are the result of marketing, financial, or competitive constraints. All of these factors will influence the design and production of simulation tools. A manager, scientist, or engineer who is involved in development of this kind of innovative product may be helped by considering the impact of some of these decisions earlier in the process. Forewarned is fore-armed. The most basic design issue we faced was the conflict between the requirements we envisioned for the ultrasound simulator, and the limitations of realistic simulation. Our goal was to achieve a product which would be affordable to the academic institutions who would be using it. Simulation will be defined and presented with examples from our experience.
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140
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Cardiomyocytes in culture--a model to study the cellular actions of amiodarone. ISRAEL JOURNAL OF MEDICAL SCIENCES 1996; 32:1212-6. [PMID: 9007156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The extensive use of amiodarone as an anti-arrhythmic drug is hampered by numerous side effects and by insufficient knowledge of its cellular action. The use of cell cultures for studying the mechanism of amiodarone action has been questioned, since available information has indicated that the doses employed for the experiments induce cell damage. We have defined conditions to obtain the amiodarone effect on cardiac cells in culture with no detectable damage. Amiodarone, 1 microg/ml, a concentration comparable to serum levels of the drug in acute and chronically treated humans and rats, reduces cell contractions, modifies membrane electrical properties accordingly, increases ATP content, but does not alter cell substructure or change enzyme activities. We strongly support the use of cell cultures for studying the cellular action(s) of amiodarone and offer conditions suitable for such experiments.
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141
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Abstract
No currently available bond test for dental metal ceramic systems has yet gained general acceptance. Such a bond test cannot be established without careful analysis of the stress distribution within the adherence region. The objective of the present study was to establish a mechanical shear stress test and combine the results with a finite element stress analysis of an idealized crown to enable comparisons of different metal-ceramic systems. The titanium-ceramic systems tested, both machined and cast titanium, showed higher shear strength values than the high gold-ceramic system used as a reference. Since the latter system has been used successfully in the clinic for many years, it seems reasonable to assume that the bond strength of titanium-ceramic systems is quite satisfactory for dental crown-and-bridge work. In conclusion, the interfacial bond strength test proposed in the present study should be applicable to all of the currently known material combinations in which a brittle fracture might be expected to occur.
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142
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Long-term evaluation of primary anterior chamber intraocular lens implantation in complicated cataract surgery. Int Ophthalmol 1996; 20:295-9. [PMID: 9237129 DOI: 10.1007/bf00176881] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The long-term visual outcome and complications related to the use of a semiflexible open-loop all-PMMA anterior chamber intraocular lens were evaluated in 40 eyes in which the capsular support was lost. The mean follow up time was 2.3 years (range 6 months to 6.7 years). 55% of the eyes had exfoliation syndrome. 68% (27 of 40 eyes) obtained a visual acuity of 0.5 or better, and only in one of the remaining eyes decreased visual acuity was related to cataract surgery (cystoid macular oedema). No cases of corneal decompensation, uveitis-glaucoma-hyphaema syndrome or retinal detachment have developed, and no IOLs have been explanted. Based on these results, the use of a modern anterior chamber intraocular lens can be suggested at least in old persons, if the capsular support is lost.
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143
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Ceramic inlays (Cerec) cemented with either a dual-cured or a chemically cured composite resin luting agent. A 2-year clinical study. Acta Odontol Scand 1995; 53:325-30. [PMID: 8553810 DOI: 10.3109/00016359509005995] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
On the basis of the criteria of the California Dental Association (CDA), 66 CAD/CAM-manufactured ceramic class-II inlays (Cerec) were compared intraindividually after they had been cemented with either a chemically cured or a dual-cured composite resin luting agent in 27 patients. Plaque and gingival conditions, the overall time consumption for producing each inlay, and the frequency of postoperative sensitivity were also evaluated. There was no statistically significant difference between the two luting agents with regard to the properties evaluated. One inlay was replaced owing to fracture of the restored tooth just before the 24-month re-examination. After 2 years excellent CDA ratings were obtained for color in 92% of the remaining 65 inlays. The corresponding figures for surface and for anatomic form were 100% and 85%, respectively. For margin integrity 85% of the 33 inlays cemented with the dual-cured luting agent and 88% of the 33 inlays cemented with the chemically cured luting agent were rated excellent after 2 years.
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144
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Abstract
Forty-eight patients with 50 severe fractures of the proximal tibia were followed prospectively for 2-4 years (mean 2.7 years) to evaluate the use of limited internal fixation combined with external fixation in the treatment of these injuries. There were 27 men and 21 women ranging in age from 20 to 74 years. Fractures were classified according to the A0 system (Mast J, Ganz R, Jacob R: Planning and reduction technique in fracture surgery. Berlin, Springer-Verlag, 1989), which included 5 A3, 6 C1, 16 C2, and 23 C3 fractures. All patients in this series healed; 48 fractures healed in an average of 12 weeks without subsequent surgery. There were two (4%) nonunions requiring bone graft. The average hospital special surgery knee score was 90 (68-100). Grading criteria for anatomical outcome revealed there were 17 (34%) excellent results, 24 (48%) good results, 6 (12%) fair results, and 3 (6%) poor results. In conclusion, this treatment method is associated with a high percentage of good and excellent results. Combined internal and external fixation combines the advantages of anatomic, stable fixation with less soft-tissue dissection and eliminates the need for large implants.
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145
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Interactions between the tyrosine kinases p56lck, p59fyn and p50csk in CD4 signaling in T cells. Eur J Immunol 1995; 25:919-25. [PMID: 7737294 DOI: 10.1002/eji.1830250409] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Interaction of the CD4 co-receptor with major histocompatibility complex (MHC) class II molecules during antigen presentation results in enhancement of antigen receptor signaling. The synergism between the two receptors is believed to result from the juxtaposition of the CD4-associated tyrosine kinase p56lck with the cytoplasmic domains of CD3 complex components. Here, we report that cross-linking of CD4 on the surface of Jurkat cells using monoclonal antibodies results in activation of the CD3-associated kinase p59fyn. Co-cross-linking of CD4 and CD3 results in synergistic activation of p59fyn. The p59fyn kinase is also hyperactive in a Jurkat cell line stably transfected with a constitutively active p56lck mutant, indicating that p56lck mediates CD4 activation of p59fyn. In support of this hypothesis, expression of a dominant inhibitory mutant of p59fyn blocks CD4 signals involved in gene activation. In addition, the p59fyn dominant inhibitor mutant blocks gene-activating signals induced by expression of a constitutively active mutant of p56lck. Overexpression of the regulatory kinase p50csk, which attenuates TcR signaling by inactivation of p59fyn, inhibits signaling from the constitutively active form of p56lck. Taken together, these data suggest that CD4/p56lck enhancement of TcR signaling is, at least in part, mediated by activation of p59fyn, and may be regulated by p50csk.
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Effects of amiodarone on beating rate and Na-K-ATPase activity in cultured neonatal rat heart myocytes. GENERAL PHARMACOLOGY 1995; 26:285-90. [PMID: 7590075 DOI: 10.1016/0306-3623(94)00178-p] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
1. The purpose of this study was to examine the possibility that the cellular action of amiodarone is mediated by inhibition of thyroid hormone regulatory functions within the myocardial cell. We measured the rate of cell beating and the activity of Na-K-ATPase in cultured neonatal rat heart myocytes. 2. Amiodarone (0.25 and 1 microgram/ml) reduced beating rate up to 75% within 20 min, and Na-K-ATPase activity up to 40% within 2 hr. No toxic effects were detected in the treated cells. 3. The inhibitory actions of amiodarone on beating rate and Na-K-ATPase activity were the same in myocytes grown in the presence or absence of 3-iodothyronine (T3, 5 nM). 4. These data indicate that amiodarone affects beating rate and Na-K-ATPase activity independently of thyroid hormone. It is suggested that interference of amiodarone with thyroid hormone action is not the only mechanism by which this drug modulates some functions of the myocardial cell.
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147
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Abstract
Continuous measurements of mercury vapor in the breathing zone of the dentist were made under ordinary clinical conditions. Fifty old amalgam fillings were removed and replaced by new ones. The mercury vapor measurements were performed by means of atomic absorption spectrophotometry. On the basis of the type of suction device used, the measurements were divided into seven groups, each of which consisted of a series of measurements. During the cutting, filling, and polishing operations the mean mercury vapor levels in the breathing zone of the dentist were in the range of 1-2 micrograms Hg m-3 air when proper mercury hygiene measures were taken. This is far below the currently valid threshold limit value (30 micrograms Hg m-3 air) in Sweden. The saliva extractor and the dental mirror-evacuator did not influence the mercury vapor levels when used together with the high-volume evacuator. However, when only a saliva extractor was used, the cutting of amalgam fillings caused highly fluctuating mercury vapor levels, which were 2-15 times higher than the threshold limit value.
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148
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Overexpressed Csk tyrosine kinase is localized in focal adhesions, causes reorganization of alpha v beta 5 integrin, and interferes with HeLa cell spreading. Mol Cell Biol 1995; 15:711-22. [PMID: 7529872 PMCID: PMC231937 DOI: 10.1128/mcb.15.2.711] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The C-terminal Src kinase p50csk phosphorylates Src family tyrosine kinases and down-regulates their activity in vitro. To gain insight into the cellular functions of this potentially antioncogenic enzyme, we have overexpressed the csk cDNA by using an inducible promoter in HeLa cells. Despite some differences in basal Src activity in the clones analyzed, Src activity was not significantly suppressed, while the amount of p50csk and Csk activity increased at least 10-fold during 3 days of induction. Immunofluorescence for the induced p50csk was localized in the cytoplasm and distinctly in focal adhesions, in which the amount of phosphotyrosine containing proteins was also increased. Point and deletion mutagenesis experiments showed that localization in focal adhesions was dependent on the SH2 and SH3 domains of Csk but not on its catalytic activity. Csk formed a complex with the focal adhesion protein paxillin in cells, and its SH2 domain was shown to interact with pp125FAK and paxillin in vitro. After Csk induction, the cells became spherical and more loosely attached to the culture substratum, and the alpha v beta 5 integrin complex (vitronectin receptor) of focal adhesions was redistributed to a novel type of structure consisting of punctate plaques on the ventral cell surface. These phenotypic changes occurred in several clones analyzed and were totally reversible when Csk was switched off, but they did not occur in cells overexpressing the catalytically inactive Csk R-222 mutant or luciferase. Our results thus show that a fraction of cellular Csk is targeted to focal adhesions via its SH2 and SH3 domains, probably interacting with tyrosyl-phosphorylated focal adhesion proteins. They also suggest that Csk is involved in the regulation of integrins controlling cell attachment and shape.
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149
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Rak, a novel nuclear tyrosine kinase expressed in epithelial cells. CELL GROWTH & DIFFERENTIATION : THE MOLECULAR BIOLOGY JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER RESEARCH 1994; 5:1347-55. [PMID: 7696183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We have identified a new tyrosine kinase from human breast cancer cells called Rak (a Russian word for cancer) that shares 51% identity with c-Src. Sequencing of the full-length complementary DNA revealed that Rak is a tyrosine kinase with a molecular weight of 54,000 that contains SH2 and SH3 domains, as well as tyrosine residues analogous to the autophosphorylation and regulatory tyrosines of the Src family. Biochemical and site-directed mutagenesis analyses revealed that a carboxy-terminal peptide of p54rak was phosphorylated by a cytoplasmic tyrosine kinase (CSK) and that, as in the Src family, it is the COOH-terminal tyrosine that is phosphorylated by CSK. However, there were some properties of Rak that are distinct from Src-like kinases: (a) expression of Rak was predominantly in epithelial-derived cell lines and tissues, especially normal liver and kidney, and cell lines of breast and colon origin; (b) Rak does not harbor the NH2-terminal glycine essential for myristylation and membrane localization; and (c) Rak possesses a putative bipartite nuclear localization signal in the SH2 domain, and subcellular fractionation studies revealed that p54rak resides predominantly in the nucleus. In addition, p54rak was overexpressed in subsets of primary human epithelial tumors, suggesting that p54rak may have a role in human cancer. Thus, Rak is a novel epithelial-associated nuclear tyrosine kinase that may represent a unique subfamily of the Src-related kinases.
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A multinational study of the effects of low-dose pravastatin in patients with non-insulin-dependent diabetes mellitus and hypercholesterolemia. Pravastatin Multinational Study Group for Diabetes. Clin Cardiol 1994; 17:558-62. [PMID: 8001304 DOI: 10.1002/clc.4960171009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
This multinational, 16-week, randomized, double-blind, placebo-controlled study evaluated the efficacy and safety of low-dose pravastatin in 325 patients with non-insulin-dependent diabetes mellitus (NIDDM) and hypercholesterolemia [serum total cholesterol concentrations of 5.2-7.8 mmol/l (200 to 300 mg/dl)]. Patients were randomized to receive pravastatin 10 mg or matching placebo with doubling of the dose after 8 weeks if predefined target levels for total cholesterol [(i.e., < 5.2 mmol/l (200 mg/dl) or > 15% decrease from baseline] had not been achieved. At Week 16, pravastatin-treated patients showed a 21.4% decrease in serum low-density lipoprotein cholesterol (LDL-C) and a 13.5% reduction in serum total cholesterol (TC) concentrations (p < 0.001 compared with placebo). Levels of triglycerides (TG) were reduced 9.6% during pravastatin treatment (p < 0.05 compared with placebo) while high-density lipoprotein cholesterol (HDL-C) levels were increased 4.4% (p = NS). Adverse events and laboratory test abnormalities were similar among patients treated with pravastatin or placebo. Glycosylated hemoglobin (HbA1C) levels remained unchanged. The results of this study demonstrate that low-dose pravastatin is effective and well tolerated for lowering elevated cholesterol concentrations during short-term treatment of patients with NIDDM and hypercholesterolemia.
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