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91.
Summary The relationship between plasminogen activator (PA)/plasminogen activator inhibitor (PAI) activity and morphological differentiation was investigated in human neuroblastoma (NB) cells treated with retinoic acid (RA). Conditioned medium from nine NB cell lines and one closely related neuroepithelioma line was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and zymography. All NB cell lines were shown to secrete urokinase (UK)-type PA (mol. wt., 52 kDa), and all except two produced tissue PA (mol. wt., 65 kDa). Identification of the PAs was made based on molecular weight and sensitivity to inhibition by anti-UK and anti-tPA antibodies. Several cell lines expressed PA inhibitory molecules; two molecular-weight forms were observed (35 and 40 kDa) in different cell lines. Complex formation with[125]I-labelled proteases revealed specific binding with UK and trypsin but not thrombin, plasmin, or kallikrein. After treatment for 6 days with 1 M RA, six of the cell lines exhibited an increase in cell-associated and/or secreted tPA activity, corresponding to morphological differentiation of the cells as manifested by extensive neurite outgrowth. A decrease in UK and UK-complex secretion was observed in several of these cell lines. Three cell lines exhibiting no detectable morphological alterations with RA treatment also showed no dramatic changes in PA/PAI activity. These results suggest that morphological differentiation of NB cells may be associated with alterations in the regulation of PA activity.Abbreviations NB
neuroblastoma
- RA
retinoic acid
- PA
plasminogen activator
- PAI
plasminogen activator inhibitor
- SDS
sodium dodecyl sulfate
- UK
urokinase
- tPA
tissue plasminogen activator 相似文献
92.
Mosaic ring 12p and total anomalous pulmonary venous return 总被引:1,自引:0,他引:1
Harris DL Siu BL Hummel M Harbert K Senft J Sargent L Wenger SL 《American journal of medical genetics. Part A》2004,131(1):91-93
An infant born with total anomalous pulmonary venous return (TAPVR) was found to have an extra chromosome present as a small ring. Spectral karyotyping and FISH analysis identified the material as a duplication involving the short arm of chromosome 12. Previous cases describing a variety of cytogenetic abnormalities that have been associated with TAPVR are reviewed along with prior cases of duplication 12p with their associated findings. We believe ours is the first case to report the occurrence of mosaic ring 12p and its association with TAPVR. 相似文献
93.
The clinical and pathological features of a case of malakoplakia of the adrenal gland occurring in a woman with Escherichia coli infection are described. This lesion mimicked a neoplasm, the true diagnosis only being revealed by histological examination. The light and electron microscopic features are described and it is suggested that malakoplakia is due to an abnormal macrophage response to E coli infection. 相似文献
94.
Jonathan D. Katz Parunag Nishanian Ronald Mitsuyasu Benjamin Bonavida 《Journal of clinical immunology》1988,8(6):453-458
The acquired immunodeficiency syndrome (AIDS) is defined in clinical terms by the development of Kaposi's sarcoma and/or severe opportunistic infections in persons without predisposing conditions. A hallmark of the syndrome has been a decrease in the number of CD4+ T helper cells. The reduction in the frequency of the CD4+ lymphocytes has been postulated to be primarily the result of human immunodeficiency virus (HIV) tropism and cytophathogenicity for the T-cell subset. Yet only a small percentage of cells is actually infected with HIV. Recently, we provided evidence indicating that AIDS patients' natural killer cells can mediate normal levels of antibody-dependent cellular cytotoxicity (ADCC) despite exhibiting a defect in natural killer (NK) effector function (J Immunol 139:55, 1987). This finding prompted us to investigate whether AIDS patients' effector cells could mediate ADCC against circulating CD4+ T cells infected with or expressing HIV antigen. The findings reported herein demonstrate that AIDS effector cells can mediate lysis of CEM (CD4+ T-cell line) coated with HIV protein in the presence of HIV-specific antibody. Lysis was specific, as non-HIV-coated CEM or the addition of HIV-negative serum resulted in no lysis. We then examined HIV-coated peripheral blood-derived CD4+ T lymphocytes as targets in ADCC. We demonstrate that in the presence of HIV-specific antibody, HIV-coated CD4+ T lymphocytes serve as targets for ADCC by AIDS effector cells. The lytic activity obtained with AIDS effector cells was comparable to that obtained with normal effector cells. These results demonstrate that AIDS effector cells can mediate ADCC against HIV-coated CD4+ T lymphocytes and suggest that ADCC may play a rolein vivo in the pathogenesis of AIDS. 相似文献
95.
96.
Developmental Progression in Children's Knowledge of AIDS: Implications for Education and Attitudinal Change 总被引:1,自引:1,他引:1
Osborne Mary L.; Kistner Janet A.; Helgemo Benjamin 《Journal of pediatric psychology》1993,18(2):177-192
The effectiveness of curricula designed to enhance a child'sunderstanding of AIDS may hinge partially upon incorporatinginformation adjusted to the child's developmental status. Accordingly,we examined the developmental progression of children's understandingof illness transmission in general and AIDS in particular, aswell as explored the relation between a child's knowledge ofAIDS and his/her attitudes toward persons with AIDS. Knowledgeof AIDS was manipulated through use of a brief educational intervention.Results support a developmental progression in knowledge aboutAIDS that is consistent with progressions related to illnessesin general. Knowledge enhancement was associated with positivechanges in attitude. 相似文献
97.
Virtual auditory space (VAS) stimuli based on outer ear transfer functions became increasingly important in spatial hearing research. However, few studies have investigated the match between responses of auditory neurons to VAS and free-field (FF) stimulation. This study validates acoustic spatial receptive fields (SRFs) of 183 individual midbrain units using both VAS and FF stimuli. The first-spike latency, which varied systematically across SRFs, was 14.9 +/- 8.3 (SD) ms in FF, and 15.1 +/- 8.3 ms in VAS. Spike-count-based SRFs measured 0-20 dB above the neural threshold covered on average 44.5 +/- 18.0% of the recorded sphere in FF and 45.5 +/- 18.7% in VAS. The average deviation of the centroid position of SRFs using FF and VAS stimuli was 7.4 degrees azimuth and 3.3 degrees elevation. The average spike rate remained unchanged. The SRF overlap recorded using FF and VAS stimuli (mean: 71.3 +/- 12.6%) or repeated FF stimuli (70.2 +/- 14.2%) was high and strongly correlated (r = 0.96; P < 0.05). The SRF match observed with FF and VAS stimuli was not significantly altered over a range of stimulus levels (paired t-test P = 0.51; n = 6). Randomized VAS barely affected SRF sizes, centroids, or maximum spike count but decreased the average minimum response to 59% compared with sequential stimulation (paired t-test; P = 0.05; n = 26). SRF recordings in VAS excluding the acoustic distortions of the recording equipment differed from those in VAS incorporating the equipment (paired t-test P = 0.01; n = 5). In conclusion, neurophysiological recordings demonstrate that individualized VAS stimuli provided a good simulation of a FF environment. 相似文献
98.
Characterization of the sleep-wake patterns in mice lacking fatty acid amide hydrolase 总被引:2,自引:0,他引:2
STUDY OBJECTIVES: Oleamide and anandamide are fatty acid amides implicated in the regulatory mechanisms of sleep processes. However, due to their prompt catabolism by fatty acid amide hydrolase (FAAH), their pharmacologic and behavioral effects, in vivo, disappear rapidly. To determine if, in the absence of FAAH, the hypnogenic fatty acid amides induce an increase of sleep, we characterized the sleep-wake patters in FAAH-knockout mice [FAAH (-/-)] before and after sleep deprivation. DESIGN: FAAH (-/-), FAAH (+/-), and FAAH (+/+) mice were implanted chronically for sleep, body temperature (Tb), and locomotor activity (LMA) recordings. Sleep-wake states were recorded during a 24-hour baseline session followed by 8 hours of sleep deprivation. Recovery recordings were done during the 16 hours following sleep deprivation. Total amount of wake, slow-wave sleep, and rapid eye movement sleep were calculated and compared between genotypes. The electroencephalographic spectral analysis was performed by fast Fourier transform analysis. Telemetry recordings of Tb and LMA were carried out continuously during 4 days under baseline conditions. SETTING: N/A. PATIENTS OR PARTICIPANTS: FAAH (-/-) mice and their heterozygote (+/-) and control (+/+) littermates were used. INTERVENTIONS: Sleep deprivation. MEASUREMENTS AND RESULTS: FAAH (-/-) mice possess higher values of slow-wave sleep and more intense episodes of slow-wave sleep than do control littermates under baseline conditions that are not related to differences in Tb and LMA. A rebound of slow-wave sleep and rapid eye movement sleep as well an increase in the levels of slow-wave activity were observed after sleep deprivation in all genotypes. CONCLUSION: These findings support the role of fatty acid amides as possible modulators of sleep and indicate that the homeostatic mechanisms of sleep in FAAH (-/-) mice are not disrupted. 相似文献
99.
Primm BJ Perez L Dennis GC Benjamin L Clark W Keough K Leak WD Payne R Smith D Sullivan LW;National Medical Association 《Journal of the National Medical Association》2004,96(9):1152-1161
ISSUE: Inadequate pain management is a serious public health problem that affects a wide cross-section of Americans. Patients are often denied sufficient medication, because physicians lack training and fear scrutiny from federal and state regulatory agencies. In addition, even the state-financed system of care, Medicaid, has been increasingly denying payment for the best treatment for pain management. These factors are complicated by physician bias about various subgroups and poor physician-patient communication. Comprehensive patient assessment plays a crucial role in determining appropriate treatment and identifying potential abuse problems. Physicians must routinely document medications analgesic effects and screen for potential ill effects and drug abuse. OBJECTIVE: To examine the prevalence of the undertreatment of pain, particularly among African Americans, and to recommend relevant proactive policy and practice changes to aid in eliminating this health problem. CONSENSUS PROCESS: In July 2002, the NMA convened the "Managing Pain: The Challenge in Underserved Populations: Appropriate Use versus Abuse and Diversion" Consensus Meeting in Washington, DC. The country's most renowned experts in the area of pain management and substance abuse reviewed substantial information regarding pain management and substance abuse including the following: --A draft summary paper on pain management and substance abuse that served as briefing material for consensus members; --Annotated bibliographies; --Articles on pain management and substance abuse; and --Key presentations on pain management and substance abuse. 相似文献
100.