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61.
Adhesive interactions between leukocytes and endothelium are required for subsequent leukocyte extravasation toward inflammatory sites. Understanding the possible kinetic expression of vascular cell adhesion molecule-1 (VCAM-1) in the middle ear cavity during an inflammatory cascade in vivo may be important for clarifying local immunological responses in otitis media. Two inflammatory models were produced in the rat and involved acute middle ear mucosal and cutaneous inflammation induced after inoculation or intradermal injection of lipopolysaccharide (LPS). After intravenous injection of both 125I-labeled anti-VCAM-1 and 131I-labeled control monoclonal antibody (mAb), the kinetic expression of VCAM-1 in the middle ear and skin was assessed by local radionuclide uptake. The biodistribution of an 125I-labeled anti-VCAM-1 mAb as a potential detector of focal inflammation was examined in normal rats. Both inflammatory lesions were characterized by early and sustained (up to 24 h) expression of VCAM-1, with maximal expression at 4 h after LPS stimulation. The kinetics of VCAM-1 expression was similar among the middle ear mucosa or skin specimens studied and different stimulation methods. A similar biodistribution and clearance of radioactivity between 125I-labeled anti-VCAM-1 mAb and 131I- or 99mTc-labeled control mAb were observed. The present result suggest that functional VCAM-1 induced by LPS is expressed in both middle ear tissue and skin lesions and may play a role in the initial stage of inflammatory response produced. Although VCAM-1 upregulation is a very early event in the inflammatory cascade, 125I-labeled anti-VCAM-1 mAb may be useful for the early detection of focal inflammation in the middle ear.  相似文献   
62.
When cerebellar granule cells that had been cultured in vitro for 8 days were subjected to a cytotoxic glutamate pulse (100 microM, 30 min incubation), the response varied according to cell density and the volume of medium in which cells were grown. Thus, lowering the cell density by a factor of 4 compared with usual conditions (2.6 x 10(5) cells/cm2) or increasing the volume by an identical 4-fold factor reduced cell death from 90-95% to 20-30%. Addition of a conditioned medium derived from high-density to low-density cultures or to high-volume cultures markedly increased the sensitivity of the cells to glutamate. This glutamate-sensitizing activity, which accelerated by several days the onset of the response of cerebellar cultures to glutamate, was inhibited by actinomycin D and was not detectable in conditioned medium derived from confluent cultures of cerebellar astroglia, or from cell lines such as PC12, GT1-7, 3T3 and CHP 100. Glutamate-sensitizing activity was not mimicked by trilodo-L-thyronine, insulin-like growth factor-I (IGF-I), truncated IGF-I, GPE [a tripeptide (gly-pro-glu) derived from IGF-I], brain-derived neurotrophic factor (BDNF), basic fibroblast growth factor or tumour necrosis factor-alpha. However, IGF-I added to cultures of granule cells plated at high density and grown in basal medium Eagle's without serum or any other constituent of chemically defined media was capable of supporting production of glutamate-sensitizing activity to an extent similar to that shown by whole fetal calf serum. Under the same conditions triiodo-L-thyronine and BDNF did not support the production of glutamate-sensitizing activity. Glutamate-sensitizing activity was not mimicked by glutamate, NMDA, glycine or lactate, and was not inhibited by glucose, haemoglobin or N-omega-nitro-L-arginine methyl ester. At variance with the response of granule cells, the response to glutamate of GABAergic cells present in the same culture was not affected by cell density or by glutamate-sensitizing activity.  相似文献   
63.
64.
An efficient, reliable and easily programmed method for solving systems of equilibrium stage separation devices is described. The method is an extension of an algorithm developed by Ishii and Otto(9) for single columns. It solves all equations simultaneously, takes advantage of the basic tridiagonal matrix form form of the linearized steady state equations and can handle configurations which include distillation columns, absorbers and reboiled absorbers. The solution for a thermally coupled distillation system is presented.  相似文献   
65.
After the cloning of murine cytokine synthesis inhibitory factor, it was recognized that a homologous open reading frame was encoded within the Epstein-Barr virus (human herpes virus 4). This viral protein has now been termed viral interleukin 10 (vIL-10) to reflect its protein sequence homology to "cellular" IL-10 (cIL-10, either murine or human IL-10). It is now widely accepted that vIL-10 shares many functions with cIL-10, principally, the ability to enhance survival of newly infected B cells and to diminish the production of IFN-gamma and IL-2 during ongoing immune reactions. The immunomodulatory effect of locally secreted vIL-10 and murine IL-10 (mIL-10) was examined in tumor models using CL8-1 (a BL6 melanoma cell line transfected with the H-2Kb class I gene) in syngeneic animals. Although parental BL6 tumor cells grow in immunocompetent syngeneic hosts, CL8-1 are rejected. To achieve local secretion of vIL-10, we generated vIL-10 retroviral vectors. While nontransduced CL8-1 cells (1 x 10(4)) failed to grow when injected intradermally in C57BL/6 mice, CL8-1 cells (1 x 10(4)) transduced with vIL-10 formed palpable tumors and eventually killed 80% of injected animals. Suppression of tumor rejection was also noted when CL8-1 tumors with or without vIL-10 transfection were admixed with syngeneic vIL-10-transfected fibroblasts and inoculated. Since the in vitro proliferation of the tumor was not altered after transduction with the vIL-10 gene and injection of vIL-10-transduced CL8-1 does not affect the rejection of nontransduced CL8-1 inoculated at a distant site, local vIL-10 secretion appears to suppress the process of immune rejection of the target cells in a dose-dependent manner. Similar results were observed for the H-2b MCA105 sarcoma tumor model in allogeneic BALB/c mice (H-2d). Although all animals that received nontransfected MCA105 rapidly rejected these tumors, MCA105 sarcomas transfected with vIL-10 remained palpable for up to 37 d. The local immunosuppressive effect of gene-delivered vIL-10 could be neutralized by anti-human IL-10 monoclonal antibody or could be reversed by the systemic administration of IL-2 or IL-12. In marked contrast, mIL-10 transfection of CL8-1 significantly suppressed tumor growth and frequently led to the rejection of tumor. Similar results were obtained for the murine tumor cell lines MCA102.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
66.
Chitosan derivatives, sulfated N-acyl-chitosan (S-Cn-chitosan) possessing various lengths of alkyl chain, were prepared, and the properties of their aqueous solutions were examined. The 1H-NMR spectrum of D2O solutions of S-C12-chitosan showed broadening of the proton signals caused by aggregation of the alkyl chain. The solubility of a hydrophobic compounds, azobenzene, was small in the aqueous solutions of S-Cn-chitosan with shorter alkyl chains, but increased with increasing length of the chains above C10, showing that micelles had been formed. The ESR spectrum of a spin probe, TEMPO, in an S-C14-chitosan solution showed the existence of a hydrophobic region in the solution, but this region did not exist in the S-C2-chitosan solution. The rigidity of this region was examined by using a spin probe, 16-doxyl-stearic acid. From these results, it was revealed that S-Cn-chitosan with longer alkyl chains formed a novel type of micelle called a "polymer micelle," which was more stable than the ordinary micelles formed from low-molecular-weight surfactants.  相似文献   
67.
Malignant mesothelioma is caused almost exclusively by occupational exposure to asbestos. During the past few years, however, increasing evidence has mounted that background exposure to asbestos could be sufficient to cause mesothelioma. Treatment of malignant mesothelioma remains a big problem. Some new approaches are on their way, and the most exciting ones are local immunotherapy in very early cases. Some success has been reported with local interferon treatment. As for treatment of metastatic pleural disease, the main purpose is symptomatic relief of dyspnea caused by fluid accumulation. The best way to achieve a lasting palliation is pleurodesis, and the most common way to do this, is by chemical means. The drug of choice in the United States has for many years been tetracycline, but since injectable tetracycline is no longer available, some substitute must be found. The substance that will "win" is not yet clear, but the two leading contestants are talc and doxycycline. Bleomycin also has its supporters, and a dark horse is quinacrine, which although not easily available in the United States, has been used in many European centers for decades.  相似文献   
68.
Human immunodeficiency virus (HIV)-associated nephropathy (HIVAN) is a clinicopathologic entity that includes proteinuria, azotemia, focal segmental glomerulosclerosis or mesangial hyperplasia, and tubulointerstitial disease. The incidence of HIVAN is increased in black patients and variable depending on the age and geographic area. The objective of this study was to describe relevant clinical and pathological findings in 30 children with HIVAN followed at the Children's National Medical Center in Washington, D.C. Our experience of the last 12 years showed a spectrum of HIVAN that seems to be coincident with the degree of acquired immunodeficiency syndrome (AIDS) symptomatology. By renal sonograms and frequent urinalysis, we identified children undergoing the early stages of HIVAN with enlarged echogenic kidneys, proteinuria, and "urine microcysts". HIVAN did not necessarily progress rapidly to end-stage renal disease. Nephrotic syndrome or chronic renal insufficiency were late manifestations of HIVAN. Children with HIVAN were likely to develop transient electrolyte disorders, heavy proteinuria, and acute renal failure due to systemic infectious episodes or nephrotoxic drugs. HIVAN was associated with other HIV-induced illnesses and high mortality rates. Early detection and careful clinical follow-up of children with HIVAN may reduce the incidence of renal-cardiovascular complications and improve their quality of life.  相似文献   
69.
OBJECTIVE: With recent advances in molecular genetics, the rate-limiting step in identifying susceptibility genes for psychiatric disorders has become phenotype definition. The success of psychiatric genetics may require the development of a "genetic nosology" that can classify individuals in terms of the heritable aspects of psychopathology. The authors' aim is to begin to apply this analysis to the anxiety disorders, focusing on panic and phobic disorders. METHOD: Two parallel traditions of defining anxiety phenotypes are reviewed: the first, more closely identified with clinical psychiatry, has identified categorical diagnoses (e.g., panic disorder and social phobia). The other, more closely identified with psychological studies of personality development, has examined dimensional traits (e.g., neuroticism) and anxious temperament (e.g., behavioral inhibition). RESULTS: The authors suggest that a genetic nosology of panic and phobic disorders may incorporate features of both traditions and discuss strategies for optimizing genetic approaches to anxiety including 1) studying phenotypic extremes, 2) identifying biological trait markers, and 3) using animal models to identify candidate loci. CONCLUSIONS: An important dividend from the effort to define the boundaries of heritable phenotypes for genetic studies of anxiety may be a refinement of the nosology of anxiety disorders.  相似文献   
70.
SH Selesnick  MT Abraham  JF Carew 《Canadian Metallurgical Quarterly》1996,17(5):793-805; discussion 806-9
Anterior rerouting of the intratemporal facial nerve in the infratemporal fossa approach is employed to access to the jugular bulb, hypotympanum, and lateral skull base, whereas posterior rerouting of the facial nerve, as employed in the transcochlear craniotomy, is most frequently used for surgery of the posterior fossa, cerebellopontine angle, prepontine region, and petrous apex. Facial nerve rerouting may lead to facial paresis or paralysis. This review of the literature is intended to define the physiologic "cost" of these procedures, so that the neurotologic surgeon can determine if the morbidity incurred in these techniques is worth the resultant exposure. Inconsistencies in reporting facial function places into question the validity of some of the cumulative data reported. Postoperatively, grades I-II facial nerve function was seen in 91% of patients undergoing short anterior rerouting, 74% of patients undergoing long anterior rerouting, and 26% of patients undergoing posterior complete rerouting. Although facial nerve rerouting allows unhindered exposure to previously inaccessible regions, it is achieved at the cost of facial nerve function. Facial nerve dysfunction increases with the length of facial nerve rerouted.  相似文献   
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