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11.
The frequencies of anti-interferon-beta (IFN-beta) antibody development reported to date in patients treated with different IFN-beta preparations are not readily comparable mainly because of differences in underlying diseases and assay methods. Thus, the frequency of neutralizing antibody (NAb) and binding antibody (BAb) development was analyzed in a sample of sera derived from a homogeneous group of relapsing-remitting multiple sclerosis (RRMS) patients treated with different IFN-beta preparations. The frequency of developing NAb and BAb to IFN-beta varied according to the IFN-beta given. Specifically, the NAb seroconversion frequency was significantly higher in patients treated with Betaferon, Schering AG, Berlin, Germany (31.3%) than in patients treated with both preparations of recombinant IFN-beta 1a (Rebif, Serono, Geneva, Switzerland [7.4%] or Avonex, Biogen, Cambridge, MA [6.3%]). Analysis of BAb seroconversion frequency in the same patients revealed that different IFN-beta preparations may also have different capability to induce BAb development and that BAb are produced during IFN-beta therapy at a significantly higher rate than NAb. Our main conclusion is that different human IFN-beta preparations may possess different immunogenicities, leading to varying frequency of development of antibody to IFN-beta in RRMS.  相似文献   
12.
We report a new case of mesothelioma that presented with an isolated lingual metastasis 14 months after initial diagnosis. The patient was a 71-year-old man with a history of pleural decortication and chemotherapy for epithelioid mesothelioma who recently complained of chronic bleeding from a nodular consolidation of tongue. There was no clinical or instrumental evidence of extrathoracic tumor spread. Microscopic examination of a lingual biopsy specimen revealed nests of atypical polygonal cells with moderate cytoplasm, immunopositive for keratins, epithelial membrane antigen, vimentin, thrombomodulin, and calretinin. This case provides additional evidence that mesothelioma could rarely, but not exceptionally, metastatize, to unusual sites such as the tongue. In that location it can mimic primary poorly differentiated squamous carcinoma or adenocarcinoma as well as a number of other metastatic malignancies. In addition to obvious medicolegal implication, metastatic mesothelioma should be correctly recognized so as to avoid useless radical treatment.  相似文献   
13.
The trisomy 8 found in malignancies may derive from a constitutional trisomy 8 mosaicism (CT8M), and in these cases the trisomy itself may be regarded as the first mutation in a multistep carcinogenetic process. To assess the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8, an informative sample of 14 patients was collected. The data ascertained included chromosome analyses of fibroblast cultures and of PHA-stimulated blood cultures in patients with normal blood differential count, as well as possible CT8M clinical signs. One patient showed trisomy 8 in all cell types analyzed and undoubtedly has a CT8M; a second patient consistently showed trisomy 8 in PHA-stimulated blood cultures when no immature myeloid cells were present in blood and should be considered as having CT8M; a third patient, with Philadelphia-positive chronic myelocytic leukemia, was more difficult to interpret, but the possibility that she had CT8M is likely. A few clinical signs of CT8M were also present in these three patients. Our data indicate that the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8 is approximately 15-20%.  相似文献   
14.
BACKGROUND: Lethal varicella in immunocompetent hosts is rare and its pathogenesis is largely unknown. The discovery of glycoprotein E (gE) mutants showing attributes consistent with increased virulence in vitro and in animal models, provided a possible molecular mechanism underlying a more aggressive virus infection. However, these mutants have never been associated with unusually severe clinical cases. OBJECTIVES: To varicella-zoster virus (VZV) mutations that correlate with increased virulence. RESULTS: We report a case of fatal hepatitis caused by a VZV bearing a novel mutation on the 3B3 monoclonal antibody epitope of gE in an immunocompetent host. CONCLUSIONS: This report describes a mutant VZV responsible for an aggressive clinical course in an immunocompetent host. Linking these severe clinical presentations of VZV infection to virus mutations might provide insights into the underlying pathogenic mechanisms.  相似文献   
15.
Fugetaxis: active movement of leukocytes away from a chemokinetic agent   总被引:1,自引:0,他引:1  
Chemotaxis or active movement of leukocytes toward a stimulus has been shown to occur in response to chemokinetic agents including members of the recently identified superfamily of proteins called chemokines. Leukocyte chemotaxis is thought to play a central role in a wide range of physiological and pathological processes including the homing of immune cells to lymph nodes and the accumulation of these cells at sites of tissue injury and pathogen or antigen challenge. We have recently identified a novel biological mechanism, which we term fugetaxis (fugere, to flee from; taxis, movement) or chemorepulsion, which describes the active movement of leukocytes away from chemokinetic agents including the chemokine, stromal cell derived factor-1, and the HIV-1 envelope protein, gp120. In this article, we review the evidence that supports the observation that leukocyte fugetaxis occurs in vitro and in vivo and suggestions that this novel mechanism can be exploited to modulate the immune response. We propose that leukocyte fugetaxis plays a critical role in both physiological and pathological processes in which leukocytes are either excluded or actively repelled from specific sites in vivo including thymic emigration, the establishment of immune privileged sites and immune evasion by viruses and cancer. We believe that current data support the thesis that a greater understanding of leukocyte fugetaxis will lead to the development of novel therapeutic approaches for a wide range of human diseases.  相似文献   
16.
The proven antiangiogenic activity of zoledronic acid, a third-generation bisphosphonate widely used in bone metastatic cancer patients, led us to investigate if the vascular endothelial growth factor (VEGF)-related zoledronic acid modifications are correlated with survival advantages in advanced breast cancer patients. Forty-two consecutive breast cancer patients with scintigraphic and radiographic evidence of bone metastases were treated with a single infusion of 4 mg zoledronic acid before anticancer chemotherapy. The patients were prospectively evaluated for circulating levels of VEGF and interferon-gamma (IFN-gamma) just before and at 1, 2, 7, and 21 days after zoledronic acid infusion. Afterward, clinical outcome was prospectively monitored. The basal serum VEGF median levels were significantly decreased at each time point, but the major reduction was recorded 21 days after the infusion. In particular, 25 patients of 42 (59.5%) experienced a reduction of at least 25% in the VEGF circulating levels. In contrast, no statistically significant modifications of the IFN-gamma serum levels were recorded. We stratified patients on the basis of this VEGF reduction 21 days after the infusion. No differences in patient features were recorded between those with or without the VEGF reduction. The analysis of survival showed that patients with a reduction in the VEGF circulating levels had a longer time to first skeletal-related event (p = 0.0002), time to bone progression disease (p = 0.0024), and time to performance status worsening (p = 0.0352) than those without the VEGF reduction. No statistically significant differences were recorded in terms of overall survival and time to visceral progression. This study confirms that zoledronic acid could have an in vivo antiangiogenic property and that the VEGF modifications may represent a surrogate marker able to predict time to first skeletal-related event, time to bone progression disease, and time to worsening of performance status.  相似文献   
17.
18.
Crossed aphasia. An update   总被引:2,自引:0,他引:2  
The aim of this article is to present an update of a rare but interesting problem: crossed aphasia. This term indicates the presence of aphasia after unilateral cerebral lesion of the hemisphere ipsilateral to the patient's dominant hand. We report two cases, review the most relevant literature, and analyze clinical, neuroanatomical, and neurophysiological aspects, taking in consideration the various interpretations proposed to explain this unusual language disorder.  相似文献   
19.
This study assessed the use of transcranial Doppler ultrasound in detecting selective changes in cerebral blood flow velocity during emotional processes. The role of the respective hemispheres in emotional processing is controversial. Cerebral control of emotional processing has previously been investigated by analysis of patients with unilateral brain damage, experiments with selective stimulation of only one hemisphere, and more recently by imaging techniques measuring local cerebral blood flow. We investigated mean flow velocity continuously and simultaneously in both the right and left middle cerebral arteries (MCAs) in 16 healthy right-handed young subjects at rest and during the performance of three tasks: task 1: 15 slides with nonemotional content; task 2: 15 slides with negative emotional content; task 3: 15 slides with nonemotional content with different content from that in task 1. The three tasks produced significantly different effects on the right and left hemispheres. During the two nonemotional tasks the increase in mean flow velocity over basal values was similar in the two MCAs (task 1: left MCA = 3.27 ± 1.9%; right MCA = 3.63 ± 2.1%; task 3: left MCA = 2.42 ± 0.7%; right MCA = 2.56 ± 1.3%); the negative emotional task was accompanied by a significantly higher increase in the right (11.31 ± 1.6%) than in the left MCA (4.72 ± 3.7%; analysis of variance two-way interaction: side of recording x task, F = 43.6, P < 0.001). These results show the possibility of obtaining specific functional information from bilateral transcranial Doppler ultrasound and suggest the involvement of the right hemisphere in emotional processing. Received: 4 March 1999 Received in revised form: 29 June 1999 Accepted: 5 August 1999  相似文献   
20.
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