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81.
HLA-DR7 predicts the response to alkylating agents in steroid-sensitive nephrotic syndrome 总被引:2,自引:0,他引:2
Martin Konrad Joannis Mytilineos Hans Ruder Gerhard Opelz Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(1):16-19
There is a lack of reliable predictors of the response to alkylating agents in children with idiopathic nephrotic syndrome
(NS). HLA-DR7 is strongly associated with the frequency of relapses in steroid-sensitive NS before cytostatic therapy. We
therefore examined retrospectively the time to the first relapse and the incidence of subsequent relapses in 54 HLA-typed
children with frequently relapsing NS, after treatment with cyclophosphamide (n = 49) or chlorambucil (n = 5) for 8 or 12 weeks; 38 patients were HLA-DR7 positive and 16 negative with 80% in both groups being steroid dependent.
HLA typing was performed using serological or DNA typing methods. Renal biopsy showed minimal glomerular changes. A lower
proportion of HLA-DR7 positive than negative patients remained in remission after 3 years (36% vs. 81%, P<0.02) and 5 years (36% vs. 72%, P<0.03). In the first 3 years after cytostatic therapy the mean number of prednisone-treated relapses was 1.3/patient per year
in HLA-DR7-positive patients compared with 0.4 in negative patients (P<0.025). There was no statistically significant difference in the proportion of relapse-free patients with and without steroid
dependency. The HLA status predicts the response of NS patients to alkylating agents better than the rate of previous relapses.
Received September 19, 1995; received in revised form and accepted April 16, 1996 相似文献
82.
Markus Kohler Hans M. Eppenberger Imogen Cordt-Riehle Christian Michel 《Acta oncologica (Stockholm, Sweden)》1992,31(6):673-677
Urination frequency and cystic pressure resistance have been used as end-points to assess x-ray-induced changes of bladder function. Whole or half bladders of adult male rabbits were irradiated, caudally or cranially. The absorbed dose was 33 Gy, 36 Gy or 39 Gy, given in 5 daily fractions. Animals which received a whole bladder dose of 39 Gy or 36 Gy showed increased urination frequency and enhanced bladder pressure resistance during the whole follow-up time of 100 weeks, compared with the sham-irradiated controls. At half bladder irradiation, only the highest doses (39 Gy to the cranial part of the bladder and 39 Gy or 36 Gy to the caudal part) gave rise to a slight increase in frequency at about 20 weeks after exposure. 相似文献
83.
Jesper Carl Thomas Bro Christensen Hans von der Maase 《Acta oncologica (Stockholm, Sweden)》1992,31(7):749-753
This study presents an analysis on longitudinal tumour marker series in twenty-two patients with non-seminomatous germ cell cancers treated with cisplatinum (DDP) based combination chemotherapy. Series of alphafoetoprotein (AFP), human chorionic gonadotropin (HCG) and lactate dehydrogenase (LDH) were analyzed applying a dynamic mathematical marker model. The model analysis provided quantitated values for growth rate and treatment response in the marker producing cells. The analysis showed that LDH had to be above 2 000 U/l to be a trustworthy tumour marker. HCG producing cells tended to grow faster than AFP producing cells, and were 3-5-fold more sensitive to the chemotherapy given than AFP producing cells. Treatment response versus DDP dose appeared to be bi-phasic, but with no significant change in treatment efficiency within the given range of DDP doses. 相似文献
84.
Bone scintigraphy is the primary method for the diagnosis of skeletal métastases. This investigation is sensitive, but the interpretation must be performed in the knowledge that it is also nonspecific. Despite this, a correct diagnosis can usually be achieved. The first-hand supplementary investigation, after a doubtful scintigraphic finding, is radiography. In most cases this is sufficient for a diagnosis. When a scintigraphic abnormality cannot be adequately explained, usually because of a negative radiographic examination, a more sensitive modality must be used. Computerized tomography offers increased sensitivity and specificity, and is primarily used for this purpose. In this way contrast resolution is increased and problems caused by obscuring tissue and complicated anatomy are reduced. Since bone metastases migrate via the active bone marrow an alternative supplementary investigation is bone marrow scintigraphy. Its usefulness is restricted by disturbing activity, from the liver and the spleen, which obscures a significant part of the active marrow, and by the fact that a lesion must be of a certain size to become apparent. Magnetic resonance imaging yields excellent images of the extension of a tumor in soft tissue. Owing to high costs and restricted availability it is still mainly used for preoperative location of metastases. 相似文献
85.
Matthias Feichtinger Reingard Maria Aigner Gert Santler Hans K?rcher 《Journal of cranio-maxillo-facial surgery》2007,35(6-7):322-328
INTRODUCTION: Surgery based on computed tomography (CT) data is becoming increasingly important in the head and neck region. The technique for hardware fusion between positron emission tomography (PET) and computed tomography (CT) has only been established commercially in the last 4 years. The advantages over CT alone are obvious. The surgeon is simultaneously provided with a map of anatomical as well as of functional (metabolic) details. The fused images offer improved localization of malignant lesions and improved targeting of biopsy, especially for small lesions. PURPOSE: A new technique for image-guided tumour localization for maxillofacial surgery based on PET/CT-image fusion is described. PATIENT AND METHOD: A 78-year-old woman was admitted to this department with a tumour of the skull base. Three dimensional fusion of computed CT with positron PET images on a commercially available navigation system is described. After patient-to-image registration, a high-resolution endoscope was calibrated intraoperatively. Image-guided biopsy specimens were taken under direct visual control. CONCLUSION: PET/CT-image fusion proved extremely helpful to navigate the endoscope to the target lesion and to identify the tumour. 相似文献
86.
Johannes Irsch Rudolf Hendriks Hans Tesch Ruud Schuurman Andreas Radbruch 《European journal of immunology》1993,23(2):481-486
In activated murine B lymphocytes, immunoglobulin class switch recombination occurs as a highly regulated process which is targeted to distinct switch regions. Here we present first evidence that in human B lymphocytes, switch recombination is targeted to distinct switch regions as well. In a panel of clonally unrelated IgG1-expressing human B cells, immortalized by Epstein-Barr virus (EBV) transformation, seven out of nine cells show switch recombination between Sμ and Sγ1 on both alleles, the active and inactive one. The remaining cells show no switch recombination on the inactive IgH locus. The very strong correlation of switch recombination on both alleles of IgG1-expressing cells proves that class switch recombination to IgG1 is not random but directed in human B lymphocytes. 相似文献
87.
88.
89.
Purpose. Hydrophilic and charged solutes have a lower membrane permeability which is due to a lower partition into the lipid membrane (low solubility in the membrane phase) and/or a slower transcellular diffusion coefficient. They are therefore anticipated to be absorbed through the paracellular route, which is a consequence of diffusion and a convective volume flow through the water-filled intercellular space.
Methods. Two approaches have been used to investigate the mechanisms underlying the paracellular drug transport across the intestinal mucosa: (a) including water transport by exposing the apical side of the epithelium with a hypotonic solution, and (b) stimulated paracellular transport by widening of tight junction and increased water absorption as a consequence of the sodium-coupled transport of nutrients.
Results. Among the first studies that recognized this fluid flux dependent transmucosal transport of drugs, was one published by Oschenfahrt & Winne in 1973 and the one by Kitazawa et al. in 1975. During the last two decades the importance of this paracellular route for drug delivery have been explored in vitro and in situ.
Conclusions. The limits concerning molecular weight, shape, ionization and the effect of physiological stimulants, such as luminal concentrations of nutrients, osmolality and motility, are currently under investigation. However, recently published in vivo human data by ourselves and others indicate that the promising results obtained in vitro and in situ for various hydrophilic compounds might not be valid in quantitative aspects in humans, especially not for drugs with a molecular weight over 200. 相似文献
90.
Abstract: Mefloquine was administered in a single dose (1–30 mg/100 g) to rats in order to study its subcellular distribution and effects on rat liver lysosomal structure and function. Subcellular fractionation showed a significant enrichment of mefloquine in lysosomes. Even repeated administration of mefloquine did not affect the levels of cytochrome-P-450 or its reductase, indicating, although not proving, that it is not metabolized by this mono-oxygenase system. Mefloquine caused an expansion of the lysosomal apparatus, earliest seen by 24 h and lasting for some 7 days. Initially, cytoplasmic constituents were seen inside the lysosomes. Later, the lysosomes harboured myelin-like figures (multilamellar bodies) disappearing after 7–10 days. The proteolytic and lipolytic capacity was assessed in isolated lysosomes. Mefloquine caused increased protein degradation but decreased breakdown of lipids. Concomitantly, all five major phospholipids (phosphatidyl-choline, -ethanolamine, -inositol, -serine and sphingomyelin) increased in the lysosomes. It is concluded that: (1) mefloquine is a lysosomotropic drug that accumulates in lysosomes; (2) mefloquine impairs lipid degradation with ensuing accumulation of lipids in lysosomes; and (3) lysosomal trapping explains the high volume distribution of mefloquine. 相似文献