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31.
Much of the connective tissue degradation that takes place in periodontal diseases is mediated by proteolytic enzymes. Previous studies have focused on the action of proteinases released by invading polymorphonuclear neutrophils and macrophages, and bacterial enzymes. In view of recent work establishing that resident connective tissue cells can be induced by cytokines to bring about the destruction of their own matrix, we propose a new hypothesis. In this we envisage that a critical step is the interaction of bacterial antigens with inflammatory cells, resulting in the production of a cytokine, interleukin-1. Our interpretation of in vitro evidence is that the loss of connective tissue attachment and bone matrix resorption in periodontal diseases is mediated by metalloproteinases such as collagenase and stromelysin released by cells of the periodontium. Such proteolytic destruction can be induced by interleukin-1, whose production may not be dependent on a specific microbial flora but may be triggered by a number of organisms. It is now clear that interleukin-1 has multiple actions on both immune and non-immune cells; these include the induction of lymphocyte differentiation and proliferation and the stimulation of bone and cartilage resorption, and prostaglandin and metalloproteinase synthesis by connective tissues. It seems likely that further knowledge about the production and function of this cytokine will have an increasing impact in many diseases that involve resorption, particularly since interleukin-1-like molecules can be produced by cell types other than monocytes/macrophages, including keratinocytes and fibroblasts.  相似文献   
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The Childrens Cancer Study Group evaluated daily oral 13-cis-retinoic acid to determine its therapeutic efficacy in 28 children with advanced neuroblastoma refractory to conventional therapy. Cheilitis and fissured lips were the most common side effects; however, fewer than 50% of the patients experienced any toxicity. Two of twenty-two evaluable children demonstrated positive response to therapy. In one case, a child received the drug for 11 months. Seventeen patients demonstrated progressive disease within 28 days of the start of treatment. Three other patients with stable disease, or removed from study at day 28, were considered nonresponsive. Our data demonstrate that, when given as a single daily oral dose of 100 mg/m2, 13-cis-retinoic acid does not have significant activity in children with advanced neuroblastoma. © 1992 Wiley-Liss, Inc.  相似文献   
34.
Fish oil has been recently proposed as a possible effective treatment in inflammatory bowel disease (IBD); however, a lot of annoying side effects (ie, belching, halitosis, diarrhea, etc) affect patient compliance. We carried out a study of patient tolerance in a group of Crohn's disease (CD) patients with a new fish oil derivative consisting of 500-mg capsules of eicosapentaenoic-docosahexaenoic (EPA 40%-DHA 20%), a free fatty acid mixture (Purepa), and we also evaluated its incorporation into phospholipids, both in plasma and in red cell membranes. Five groups of 10 CD patients in remission received nine Purepa capsules daily in four different preparations (A: uncoated, B: coated, pH 5.5; C: coated, pH 5.5, 60 min time release; D: coated, pH 6.9) and 12 × 1-g capsules daily of a triglyceride preparation (Max-EPA, EPA 18%-DHA 10%), respectively. We coated three of the four Purepa preparations in order to delay the release of contents in an attempt to minimize the side effects. After six weeks of treatment, the group taking Purepa capsules, coated, pH 5.5, 60 min time release (group C) showed the best incorporation of EPA and DHA in red blood cell phospholipid membranes (EPA from 0.2 to 4.4%, DHA from 3.7 to 6.3%), and no side effects were registered, whereas in all other groups side effects were experienced in 50% or more of subjects. This new preparation will make it possible to treat patients for long periods.  相似文献   
35.
Summary During recent years, a significantly increased incidence of acute mastoiditis was observed at the University Children's Hospital, Tübingen, Germany (1975–1979: 1.4 patients/year; 1987–1992: 4.2 patients/year; p<0.05). We therefore reviewed the records of all patients with acute mastoiditis (n=58) that had been treated at the Children's Hospital between 1975 and 1992 and at the Clinic of Otorhinolaryngology between 1978 and 1992. The male to female ratio was 1.8:1 and 60.4% of the patients were younger than 24 months. Retroauricular swelling was more often observed (n=49) than protrusion of the pinna (n=45) and retroauricular redness (n=38).Streptococcus pneumoniae was the most frequently isolated pathogen. Several factors predisposing for the development of acute mastoiditis were identified. These included withholding antimicrobials for treatment of the preceding episode of otitis media; use of suboptimal agents for therapy of otitis media (penicillin and, possibly, erythromycin ethylsuccinate); and insufficient duration of treatment.
Akute Mastoiditis — wieder ein aktuelles Problem
Zusammenfassung In den letzten Jahren wurde an der Univ.-Kinderklinik Tübingen eine signifikante Zunahme der Inzidenz der akuten Mastoiditis beobachtet (1975–1979: 1,4 Patienten/Jahr; 1987–1992: 4,2 Patienten/Jahr; p<0,05). Wir analysierten daher die Krankengeschichten aller Patienten mit akuter Mastoiditis (n=58), die zwischen 1975 und 1992 an der Universitäts-Kinderklinik und zwischen 1978 und 1992 an der Universitäts-Hals-Nasen-Ohrenklinik behandelt worden waren. Das Verhältnis von Jungen zu Mädchen betrug 1,8:1, und 60,4% der Patienten waren jünger als 24 Monate. Eine retroaurikuläre Schwellung wurde häufiger beobachtet (n=48) als ein abstehendes Ohr (n=45) und eine retroaurikuläre Rötung (n=38).Streptococcus pneumoniae war der häufigste Erreger. Mehrere für das Auftreten einer akuten Mastoiditis prädisponierende Faktoren wurden gefunden: die Nichtbehandlung der vorausgegangenen Otitis media mit Antibiotika, der Einsatz suboptimaler Antibiotika (Penicillin und möglicherweise Erythromycin-Ethylsuccinat) für die Otitis-Behandlung und eine ungenügende Therapiedauer.
  相似文献   
36.
Chronic hyperphenylalaninemia (HPA) in rats has been used as an experimental model of the human inborn error of metabolism phenylketonuria (PKU). Impaired brain development in PKU and HPA is reflected in reduced myelin formation. We have used immunohistochemistry, with antibodies to cell-specific antigenic markers, to investigate the cellular basis of the hypomyelination in the corpus callosum and cerebral cortex of rats made hyperphenylalaninemic from Postnatal Days 3-17. The rats were then allowed to recover until Day 59. No effects were seen on the number and differentiation pattern of ganglioside GD3-expressing glial progenitors. Myelin basic protein and 2'3'-cyclic nucleotide 3'-phosphohydrolase (CNP) immunostaining demonstrated a reduction in myelin formation in the corpus callosum and subcortical white matter at 12 and 17 days postnatal. However, numbers of CNP+ oligodendrocytes appeared normal throughout development. No reactive astrogliosis was seen at any stage. The intensity of axonal neurofilament immunostaining was reduced in the corpus callosum at 17 days. In layers II and III of the cortical gray matter there was an increase in the cell packing density and a concomitant decrease in cell body size. Myelination in the corpus callosum was rapid during the recovery period with no difference noted at Day 59. Axonal neurofilament staining also returned to normal in the corpus callosum. However, recovery became increasingly incomplete away from the corpus callosum into the cortical gray matter. Our data suggest a primary effect of HPA on axonal maturation with hypomyelination consequential upon this.  相似文献   
37.
Heroin use is postulated to act as a cofactor in the neuropathogenesis of human immunodeficiency virus (HIV-1) infection. Astrocytes, integral components of the CNS, are reported to be susceptible to HIV-1 infection. Upon activation, astrocytes release a number of immunoregulatory products or modulate the expression of a number of proteins that foster the immunopathogenesis of HIV-1 infection. However, the role of heroin on HIV-1 infectivity and the expression of the proteome of normal human astrocytes (NHA) have not been elucidated. We hypothesize that heroin modulates the expression of a number of proteins by NHA that foster the neuoropathogenesis of HIV-1 infection. We utilized LTR amplification and the p24 antigen assay to quantitate the effect of heroin on HIV-1 infectivity while difference gel electrophoresis (DIGE) combined with protein identification through high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) to analyze the effects of heroin on the proteomic profile of NHA. Results demonstrate that heroin potentiates HIV-1 replication in NHA. Furthermore, heroin significantly increased protein expression levels for protein kinase C (PKC), reticulocalbin 1 precursor, reticulocalbin 1, tyrosine 3-monooxgenase/tryptophan 5-monooxgenase activation protein, chloride intracellular channel 1, cathepsin D preproprotein, galectin 1 and myosin light chain alkali. Heroin also significantly decreased protein expression for proliferating cell nuclear antigen, proteasome beta 6 subunit, tropomyosin 3, laminin receptor 1, tubulin alpha 6, vimentin, EF hand domain family member D2, Tumor protein D54 (hD54), ATP synthase, H+ transporting, mitochondrial F1 complex and ribosomal protein S14. Identification of unique, heroin-induced proteins may help to develop novel markers for diagnostic, preventative and therapeutic targeting in heroin using subjects.  相似文献   
38.
39.
BACKGROUND AND AIMS: The aim of this work was to test the feasibility of using a bipolar low thermal acting system inducing collagenic sealing but not protein coagulation to secure hepatic parenchyma cutting. MATERIALS AND METHODS: Thirty consecutive hepatectomies were carried out using kellyclasy plus ligatures and clips (controls), while the following 50 hepatectomies used kellyclasy plus bipolar vessels sealer (BVS). Blood loss, duration of hepatic pedicle clamping, length of hospital stay, and complications were recorded. RESULTS: There was no statistically significant difference in blood loss and duration of clamping between controls and BVS. Specific complications (9/21 in the control group vs 1/49 for the BVS group, p<0.00045) and length of hospital stay (14 days in the control group vs 11 days in the BVS group, p<0.014) were statistically lower in BVS group than in the controls, mainly due to prevention of bile duct leakages. CONCLUSIONS: Our data suggest that BVS may be particularly efficient to achieve bilistasis leading to the highest level of safety in performing hepatectomies. Further studies are now needed to confirm its superiority on the classical biliary ducts occlusion techniques.  相似文献   
40.
We report the results of a retrospective review of the outpatient pretransplantation workup for United Network for Organ Sharing (UNOS) 3 patients adopted at a liver transplantation (LT) center and illustrate the efficiency indicators used for quality evaluation and cost-analysis. A single-center, pre-LT evaluation workup was performed on an outpatient basis at a cost per patient evaluation of 2,770 Euros (). Objective measures were: the number of patients admitted to and excluded from each phase of the algorithm; the rate of patients admitted to pre-LT evaluation out of the total of referred patients (the referral efficiency rate); the rate of waitlisted patients out of those admitted to pre-LT evaluation (the evaluation efficiency rate); the rate of waitlisted patients out of those referred for LT (the process efficiency rate); and the cost per waitlisted patient, as the ratio of the cost per patient evaluation to the evaluation efficiency rate. From January 1, 1996, to October 1, 2004, 1,837 patients were referred for LT on an outpatient basis. Based on preemptive evaluation of the available clinical data, 412 patients (22.4%) were excluded from pre-LT evaluation and 1,425 (77.6%) were admitted to preliminary consultation. Among these, 603 (42.3%) were excluded from and 822 (57.7%) were admitted to pre-LT evaluation with a referral efficiency rate of 44.7% (822 of 1,837). Out of the patients evaluated for LT, 484 were waitlisted with a cost-utility and evaluation efficiency rate of 58.8% each (484 of 822). Of the 1,837 patients originally addressed for LT 484 were waitlisted, yielding a process efficiency rate of 26.3% (484 of 1,837) and a cost per waitlisted patient of 4,710.8. In conclusion, the 3 indicators allowed monitoring of the efficiency of the pre-LT evaluation algorithm. The current process efficiency rate at our center is low (26.3%), but avoiding early referrals we might increase it to 31.6%, with a 12% net saving on costs per waitlisted patient (from 4,710.8 to 4,165.4).  相似文献   
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