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81.
Ectopic lymphoid structures have been described in several tumor types including metastatic lesions, but not primary tumors, of patients with melanoma. Here we present evidence of B-cell follicles in primary cutaneous melanomas, being present in 39 of 147 cases (27 %). B-cell clusters were associated with T lymphocytes, most of which belonging to CD45RO+ memory T cells. A network of CD21+ follicular dendritic cells was demonstrated in 8 of 22 cases studied (36 %). MECA-79+ HEV-like venules were observed in the neighborhood of the follicles in the majority of cases, however, their presence was not confined to tumors hosting ectopic lymphoid structures. The appearance of B-cell aggregates did not show association with the outcome of the disease, although a trend for their higher prevalence was observed in thicker tumors. Our results show that neogenesis of lymphoid structures does occur in primary melanomas, albeit with lower frequency compared to that reported in metastases.  相似文献   
82.
Summary A phase II trial of spirogermanium was conducted in advanced previously untreated non-small cell lung cancer patients. The drug was given by intravenous infusion 3 times per week for 2 weeks, twice per week for the next 2 weeks, and then weekly. Starting dose was 125 mg/m2, and dose escalation of 25 mg/m2 per week was required in the absence of toxicity to a maximum dose of 200 mg/m2 per infusion. Fifteen eligible patients were treated, and no objective responses were seen. Primary toxicity was neurologic and reversible after withdrawal of the drug. We conclude that spirogermanium is not active against non-small cell lung cancer in the dosage used in this study.  相似文献   
83.
1. The inhibitory effect of a selective prostaglandin H2 (PGH2)/thromboxane A2 receptor antagonist, EP 092, on platelet aggregatory responses in whole blood ex vivo (guinea-pig: Rhesus monkey) and intravascular aggregation in vivo (rabbit) has been investigated. 2. Collagen (0.1-10.0 micrograms ml-1) caused a concentration-dependent decrease in single platelet count in samples of both guinea-pig and Rhesus monkey citrated whole blood incubated ex vivo. EP 092 administered to guinea-pigs by intravenous (0.1-3.0 mg kg-1) or oral (1.0-10.0 mg kg-1) routes significantly inhibited the platelet responses to collagen (ED50 values 1.3 +/- 0.2 and 1.4 +/- 0.2 mg kg-1 respectively). Similar potency against collagen-induced whole blood aggregation was observed in Rhesus monkey blood samples following EP 092 given orally (ED50 0.9 +/- 0.3 mg kg-1). 3. The duration of action of EP 092 against collagen aggregatory responses ex vivo in both guinea-pigs and Rhesus monkeys was between 3 and 6 h following oral administration at 3.0 mg kg-1. 4. The inhibitory activity demonstrated by EP 092 against collagen-induced aggregation of Rhesus monkey whole blood ex vivo was not accompanied by any significant reduction in thromboxane A2 formation except at the highest dose tested (10 mg kg-1). 5. The intravascular aggregatory response induced by collagen or thrombin in the anaesthetized rabbit was significantly inhibited by an intravenous infusion of EP 092 (10 mg kg-1). EP 092 appeared less potent and its effect was of shorter duration in this preparation compared with its inhibitory effect on ex vivo aggregation, being evident immediately after infusion of drug but not after a further 30 min. 6. It is concluded that collagen-induced platelet aggregatory response in guinea-pig and Rhesus monkey whole blood ex vivo and rabbit in vivo exhibit a thromboxane-dependent component which can be inhibited in a dose-related fashion by pretreatment with the thromboxane antagonist EP 092. In the rabbit, moreover, the data support the possibility of a role for thromboxane in the intravascular aggregatory response to thrombin.  相似文献   
84.
Human lymphocytes cultured with ethanol and subsequently assayed for natural killer (NK) activity to K562 cells have enhanced NK activity compared to lymphocytes cultured without exposure to ethanol. Optimal enhancement occurred at 0.64% (v/v) ethanol, and required several hours of culture. Lymphocytes retained their enhanced cytolytic ability for several hours after removal from the ethanol-containing medium. The enhancement correlated with a faster rate of cytolysis by ethanol-treated lymphocytes, rather than recruitment of an increased number of killer cells, as measured with single cell assays. Inclusion of ethanol directly in the NK assays was inhibitory. Cells that had been cultured with ethanol were less sensitive to inhibition of NK activity by the proteinase substrate acetyl tyrosine ethyl ester than were control cells cultured without ethanol. Although this observation and the increased rate of cytolysis in the single cell assays are consistent with increased production of a chymotrypsin-like proteinase involved in cell-mediated cytotoxicity, no alteration in protein synthesis was detected concomitant with ethanol treatment. This report demonstrates that even without hepatic metabolism, ethanol can produce effects on lymphocyte function which remain after exposure to the reagent is discontinued.  相似文献   
85.
There is paucity of data on infusion related hypersensitivity reactions (IRHR) pattern of bio-similar rituximab in B-cell lymphoma patients. As bio-similar molecules are independently developed monoclonal antibodies, they are likely to differ in immunogenicity and therefore, the hypersensitivity data of the innovator rituximab may not be directly applicable to patients treated with the biosimilar rituximab molecule. We analysed our data of 256 patients of B cell lymphoid neoplasm who received bio-similar rituximab (Reditux) based chemo-immunotherapy for their treatment. Total 56/256 (21.8%) patients had ≥ grade II IRHR with first dose of rituximab. Grade II reactions were seen in 32/256 (12.5%) cases, grade III and grade IV reactions were seen in 21/256 (8.2%) and 3/256 (1.2%) cases, respectively. Rituximab was withdrawn from all further therapy in only 2 patients due to grade IV IRHR after attempting re-challenge of the drug under intensive monitoring. There was no difference in complete response rates in patients with or without IRHR during their first rituximab infusion. The IRHRs with bio-similar rituximab noted in our study were comparable with the previously published reactions associated with the original rituximab.  相似文献   
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89.

Objective:

To determine the rate of underestimation of malignancy in patients with biopsy-proven stromal fibrosis.

Methods:

Following institutional review board approval, we retrospectively reviewed the charts of patients with biopsy-proven stromal fibrosis who underwent percutaneous breast biopsy in the 5-year period between 1 January 2005 and 31 December 2009. The medical records and the histopathology in patients who underwent repeat biopsy and/or surgical excision at the site of stromal fibrosis within 2 years were reviewed. Interval stability for up to 2 years was documented in patients who did not undergo additional biopsy or surgical excision. An upgrade was defined as any patient with biopsy-proven stromal fibrosis or fibroadenoma with evidence of malignancy at the site of biopsy within 2 years.

Results:

365 cases of stromal fibrosis were identified, of which 25 (7%) were upgraded to in situ or invasive malignancy on repeat biopsy or surgical excision. 7 were upgraded to ductal carcinoma in situ and 18 were upgraded to invasive cancer. Of the upgraded cases, 8 out of 24 (32%) were considered concordant with a benign diagnosis. The false-negative rate, that is, cases of stromal fibrosis concordant with benignity, but with subsequent upgrade, comprised 2% of all cases.

Conclusion:

In biopsy-proven cases of stromal fibrosis, there is a 7% upgrade to malignancy. We recommend that all instances of stromal fibrosis with radiology–pathology discordance undergo repeat biopsy or surgical excision. Cases that demonstrate radiology–pathology concordance can be safely categorized as a Breast Imaging Reporting and Data System 3 (BI-RADS® 3) lesion with a 6-month follow-up, owing to a false-negative rate for missed cancer of 2%.

Advances in knowledge:

We now recommend that concordant cases of stromal fibrosis be categorized as BI-RADS 3 with a short-term follow-up, as this results in a missed cancer rate of 2%.Stromal fibrosis is a histopathology diagnosis characterized by proliferation of hypocellular fibrous tissue with the obliteration or hypoplasia of mammary acini and ducts.1 Stromal fibrosis is a common finding on percutaneous breast biopsy, with an incidence ranging from 2.1% to 9.0% depending on the series.1 Stromal fibrosis has a wide spectrum of imaging appearances on mammogram, ultrasound and MRI.2,3 Although there is no generally accepted consensus on the management of stromal fibrosis, it has been suggested that the histopathology diagnosis of stromal fibrosis should be considered concordant with a benign diagnosis during radiology–pathology correlation, if accurate targeting is confirmed and in the absence of imaging features that are concerning for malignancy.4Although the cause of stromal fibrosis has not yet been fully elucidated, it has been observed that stromal fibrosis can occur as a desmoplastic response to malignancy.5 We therefore hypothesized that a proportion of percutaneous breast biopsies that demonstrate stromal fibrosis may be owing to undersampling of an adjacent malignancy (Figure 1).Open in a separate windowFigure 1.Stromal fibrosis can occur as a desmoplastic reaction to an adjacent breast carcinoma.The false-negative rate of malignancy has been investigated in other studies. Harvey et al6 reported no false-negative cases using a sample size of 38 patients and a follow-up period of 1 year. Rosen et al4 also reported no upgrades using a sample size of 80 patients and a mean follow-up period of 27 months. The series by Sklair-Levy et al1 with a sample size of 74 patients reported an incidence of 2.7% of missed cancer using a spring-loaded device. In our study, we sought to determine the upgrade rate of biopsy-proven stromal fibrosis in a 5-year retrospective review, using both spring-loaded and vacuum-assisted biopsy devices, with a larger sample size of 365 patients and a longer follow-up period of 2 years.  相似文献   
90.
I S Grewal  C V Olson  S J Scott    P M Lad 《Immunology》1987,61(2):131-135
We have examined concanavalin A (Con A)-induced cap formation in a B-lymphocyte derived cell line, LAZ-559. Treatment with pertussis toxin (PT) or phorbol-12-myristate-13-acetate (PMA) prior to exposure of the cells to Con A abolished the capping reaction. The possible role of calcium mobilization was tested using cells pre-loaded with the fluorescent dye Quin2. Both PT and PMA caused inhibition of calcium mobilization at concentrations similar to those observed for the inhibition of capping. The possible identity of the substrate for pertussis toxin was examined by carrying out ADP-ribosylation of the isolated plasma membranes using [alpha-32P]NAD and pertussis toxin. Several bands were observed at molecular weights of 109,000, 43,000, 34,000 and 22,000. Comparative labelling with cholera toxin revealed a separate band at 42,000. The bands at 43,000 and 34,000 are PT specific. Of these, the 43,000 band comigrated with the PT substrate that has been shown to regulate capping in human neutrophils (Lad et al., 1985a, 1986b). PMA-induced phosphorylation was examined in 32P-loaded cells, and multiple bands were observed to be labelled in a dose-dependent manner, at least two of which were very similar in mobility to the PT substrate. Our results suggest that regulation of calcium mobilization and the control of capping via a PMA-sensitive, GTP-binding protein are probably general phenomena observable in multiple cell systems.  相似文献   
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