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111.
Glucocorticoids are the consensus treatment for the prevention of respiratory distress in preterm infants, but there is evidence for increased incidence of neurodevelopmental disorders as a result of their administration. We administered dexamethasone (Dex) to developing rats at doses below or within the range of those used clinically, evaluating the effects on forebrain development with exposure in three different stages: gestational days 17-19, postnatal days 1-3, or postnatal days 7-9. At 24 h after the last dose, we evaluated biomarkers of neural cell acquisition and growth, synaptic development, neurotransmitter receptor expression, and synaptic signaling mediated by adenylyl cyclase (AC). Dex impaired the acquisition of neural cells, with a peak effect when given in the immediate postnatal period. In association with this defect, Dex also elicited biphasic effects on cholinergic presynaptic development, promoting synaptic maturation at a dose (0.05 mg/kg) well below those used therapeutically, whereas the effect was diminished or lost when doses were increased to 0.2 or 0.8 mg/kg. Dex given postnatally also disrupted the expression of adrenergic receptors known to participate in neurotrophic modeling of the developing brain and evoked massive induction of AC activity. As a consequence, disparate receptor inputs all produced cyclic AMP overproduction, a likely contributor to disrupted patterns of cell replication, differentiation, and apoptosis. Superimposed on the heterologous AC induction, Dex impaired specific receptor-mediated cholinergic and adrenergic signals. These results indicate that, during a critical developmental period, Dex administration leads to widespread interference with forebrain development, likely contributing to eventual, adverse neurobehavioral outcomes.  相似文献   
112.
INTRODUCTION: Whereas the involvement of elicited xenoantibodies in delayed xenograft rejection is currently being substantiated, this study focuses on the role of the preformed fraction of xenoantibodies. METHODS: To check the influence of the latter, we combined pretransplant complement inactivation (cobra venom factor) and antibody reduction (plasmapheresis) in a guinea pig-to-rat heart transplant model. RESULTS: Antibody reduction on plasmapheresis before xenografting did not prolong delayed xenorejection in decomplemented rats, although the immunohistologic pattern lacked the immunoglobulin deposits along endothelial walls found in xenografts of merely decomplemented recipients. Astonishingly, plasmapheresis, if carried out 2 days before transplantation, almost tripled xenograft survival, although preformed antibody levels were completely restored and even rebounding at the time of grafting. The pattern and number of infiltrating cells did not differ in dependence of the timing of plasmapheresis nor did the proliferative response of lymphocytes in the mixed lymphocyte reaction differ. However, plasmapheresis led to a retarded decrease of the mononuclear cell tumor necrosis factor alpha secretory potential, which correlated well with a diminished immunohistologic staining of tumor necrosis factor alpha secreted by graft-infiltrating mononuclear cells. CONCLUSION: These findings argue against a pivotal role of preformed xenoantibodies in the pathomechanistic process of delayed xenograft rejection and challenge the therapeutic strategy to reduce preformed xenoantibody levels before xenotransplantation in complement-inactivated recipients.  相似文献   
113.
Conventional treatment of cornual ectopic pregnancy carries significant morbidity and may compromise future fertility. We present a minimal access technique for the treatment of cornual ectopic pregnancies which we believe carries a reduced morbidity and may be less likely to compromise future reproductive function.  相似文献   
114.
The role of caspases in cell death and differentiation.   总被引:1,自引:0,他引:1  
The complexity, redundancy and interdependence of the biological systems involved in tumour response to different treatments hamper progress towards developing specific and effective therapies. In addition, the many and even contradictory roles played by certain key proteins can significantly amend our view on tumourigenesis. The role of caspases in the modulation of cell death and differentiation is a prominent example of such a complexity. Here we focus on the role of caspases in apoptotic cell death, mainly in haematological malignancies, tumourigenesis, sepsis, T-cell proliferation and cell differentiation.  相似文献   
115.
PURPOSE: Hodgkin's lymphoma (HL) has been demonstrated to be a good target for immunotherapy since lymphocyte activation markers such as CD30 are expressed in high numbers on the malignant cells. Thus, we developed a new radioimmunoconjugate consisting of the murine anti-CD30 monoclonal antibody (MAb) Ki-4 labeled with iodine-131 ((131)I). PATIENTS AND METHODS: The biodistribution of (131)I-Ki-4 was assessed via dosimetry after preinfusion of 5 mg native Ki-4 followed by 250 to 300 MBq (131)I-labeled Ki-4. Whole-body scintigraphy was performed 1 hour, 24 hours, 48 hours, 72 hours, and 6 days after the infusion. Dosimetry was calculated using the programs NucliDose ICON-IDL (version 5.0.2; Siemens, Erlanger, Germany) and MIRDOSE (version 3.1; Oak Ridge National Laboratories; Oak Ridge, TN). The therapeutic dose was given on day 8 after preinfusion of unlabeled Ki-4. RESULTS: We treated 22 patients with relapsed or refractory CD30-positive HL. Preinfusion of 5 mg native Ki-4 was sufficient to bind the soluble CD30. Imaging demonstrated localization of involved areas measuring 5 cm in diameter or more in four patients and 2.5 cm in one patient. Patients received total body doses of 0.035 Gy to 0.99 Gy. Acute toxicity was mild with grade 1 fatigue in 19 of 22 assessable patients. Seven patients experienced grade 4 degrees hematotoxicity 4 to 8 weeks after treatment. Response included one complete remission, five partial remissions, and three minor responses. CONCLUSION: Treatment with (131)I-Ki-4 is effective but can be associated with severe hematotoxicity.  相似文献   
116.
ContextCallistemon citrinus Skeels (Myrtaceae) exhibits many biological activities.ObjectiveThis study analyzes for the first time, the toxicity, obesogenic, and antioxidant effects of C. citrinus in rats fed with a high fat-fructose diet (HFFD).Materials and methodsFour studies using male Wistar rats were conducted: (a) 7 groups (n = 3): control (corn oil) and ethanol extract of C. citrinus leaf (single oral dose at 100–4000 mg/kg) for acute toxicity; (b) 2 groups (n = 8): control (corn oil) and C. citrinus (1000 mg/kg/day) for 28 days for subacute toxicity; (c) 3 groups (n = 4) with single oral dose of lipid emulsion: control (lipid emulsion), C. citrinus and orlistat (250 and 50 mg/kg, respectively) for lipid absorption; (d) 4 groups (n = 6): control (normal diet) and 3 groups fed with HFFD: HFFD only, C. citrinus and simvastatin (oral dose 250 and 3 mg/kg, respectively) for 13 weeks. Antioxidant enzymes and biomarkers were evaluated and inhibition of pancreatic lipase was determined in vitro.ResultsToxicological studies of C. citrinus showed no differences in biochemical parameters and lethal dose (LD50) was higher than 4000 mg/kg. C. citrinus inhibited pancreatic lipase activity, with IC50 of 392.00 µg/mL, and decreased lipid absorption by 70%. Additionally, it reduced the body weight 22%, restored the activities of antioxidant enzymes, and reduced the biomarkers of oxidative stress.ConclusionsCallistemon citrinus showed an effect against oxidative stress by reducing biomarkers and induced antioxidant system, without toxic effects.  相似文献   
117.
ObjectivesDesign and build a portable xenon-129 (129Xe) hyperpolariser for clinically accessible 129Xe lung MRI.MethodsThe polariser system consists of six main functional components: (i) a laser diode array and optics; (ii) a B0 coil assembly; (iii) an oven containing an optical cell; (iv) NMR and optical spectrometers; (v) a gas-handling manifold; and (vi) a cryostat within a permanent magnet. All components run without external utilities such as compressed air or three-phase electricity, and require just three mains sockets for operation. The system can be manually transported in a lightweight van and rapidly installed on a small estates footprint in a hospital setting.ResultsThe polariser routinely provides polarised 129Xe for routine clinical lung MRI. To test the concept of portability and rapid deployment, it was transported 200 km, installed at a hospital with no previous experience with the technology and 129Xe MR images of a diagnostic quality were acquired the day after system transport and installation.ConclusionThis portable 129Xe hyperpolariser system could form the basis of a cost-effective platform for wider clinical dissemination and multicentre evaluation of 129Xe lung MR imaging.Advances in knowledgeOur work successfully demonstrates the feasibility of multicentre clinical 129Xe MRI with a portable hyperpolariser system.  相似文献   
118.
Callus and hairy root cultures of Linum leonii were established. The genetic transformation in hairy roots was proven by PCR analysis, which showed integration of rol A and rol C genes into the plant genome. Calli and hairy roots accumulate the arylnaphthalene lignan justicidin B as a major constituent. Hairy roots produce 5-fold higher yields of justicidin B (10.8 mg g(-1) DW) compared to calli. Justicidin B shows strong cytotoxicity on the chronic myeloid leukemia LAMA-8 and K-562 cell lines and on the chronic lymphoid leukemia SKW-3 cell line with IC(50) values of 1.11, 6.08, and 1.62 microM, respectively. Apoptotic properties of justicidin B are reported for the first time.  相似文献   
119.
Purpose: The aim of our study was to investigate the biomechanical properties of the cornea in primary congenital glaucoma (PCG) and to identify the potential ocular determinants, which affect the corneal biomechanical metrics. Methods: Corneal hysteresis (CH), corneal resistance factor (CRF) and central corneal thickness (CCT) were measured in 26 patients with PCG (40 eyes) with the aid of ocular response analyser. In vivo laser‐scanning confocal microscopy was used for the estimation of stromal keratocyte density (KD) and the evaluation of corneal endothelium. Twenty normal subjects (40 eyes) served as controls. Student’s t‐test and Pearson’s correlation coefficients were used for statistical analysis. p Values <0.05 were considered statistically significant. Results: Corneal hysteresis, CRF and CCT were significantly reduced in patients with PCG (all p < 0.05). Corneal hysteresis and CRF negatively correlated with the corneal diameter in both groups (r1 = ?0.53, r2 = ?0.66, p < 0.001 for CH and r1 = ?0.61, r2 = ?0.69, p < 0.001 for CRF). Moreover, we identified a significant correlation between CH and CRF with CCT in both groups (r1 = 0.51, r2 = 0.48, p < 0.001 for CH and r1 = 0.45, r2 = 0.44, p < 0.001 for CRF). Mean KD was significantly reduced both in the anterior and posterior corneal stroma in patients with PCG (764 ± 162 and 362 ± 112 cells/mm2, respectively) compared with controls (979 ± 208 and 581 ± 131 cells/mm2, respectively) (p < 0.001). There was no significant correlation between the keratocyte density in anterior and/or posterior stroma and CH or CRF in any group (r1 = 0.29, r2 = 0.31, p < 0.06). Mean endothelial cell density was also significantly reduced in PCG group (2920 ± 443 cells/mm2) compared with control group (3421 ± 360 cells/mm2) (p < 0.001). Pleomorphism and polymegalism were significantly increased in corneal endothelium of patients with PCG. Conclusions: Our results showed a significant reduction in CH and CRF in PCG. Both CH and CRF were negatively correlated with corneal diameter. A significant correlation of CH and CRF with CCT was identified in both groups. Keratocyte density was decreased in PCG, but did not have a significant impact on CH and CRF. Mean endothelial density was also decreased in PCG. Our results suggest that reduced CCT and increased corneal diameter are major ocular determinants for the modified corneal biomechanical profile in PCG, while cellular alterations in corneal stroma and endothelium have no significant biomechanical impact.  相似文献   
120.
Effectively managing and optimizing the value of the patent portfolio is a major challenge for many firms, especially those in knowledge intensive industries, such as the pharmaceutical, biotechnological and chemical industry. However, insights on effective patent portfolio strategies are rare. Therefore, in this article we investigate in detail how firms successfully manage and optimize their patent portfolios to increase their overall competitiveness. We discover that successful patent portfolio management is rooted in managing the patents along their life cycles. Based on the findings of ten case studies, we develop a holistic patent life cycle management model reflecting five distinctive phases of patent management: explore, generate, protect, optimize and decline. We conclude with how our findings can be used in practice.  相似文献   
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