False-positive results with chemically modified anti-D do not indicate a need to use a separate, immunologically inert Rh control reagent

Thirteen of 1450 (0.9%) Rh-negative samples submitted for pretransfusion or prenatal testing gave weak false-positive reactions in immediate-spin (IS) tests with chemically modified anti-D (CM-D). Only seven reacted in control tests with anti-A and/or -B. The other six samples could have been considered Rh positive; however, such a conclusion is inappropriate, since stronger (greater than or equal to 3+) reactions are expected in IS tests with CM-D and the vast majority of true Rh-positive blood samples. Moreover, three of the six false-positive CM-D reactions associated with negative control tests were from patients previously found to be Rh negative. The other three samples gave 1+ to 2+ reactions with CM-D and did not react with anti-A and/or -B; these erroneous CM-D reactions were recognized by confirmatory tests with high-protein anti-D and Rh control reagents that were performed because previous typing results were not on file. Such confirmation, as well as careful grading and proper interpretation of serologic reactions, serves to prevent erroneous Rh typing without the use of a separate, immunologically inert Rh control reagent.     

New mutant and congenic mouse stocks expressing the murine leukemia virus-associated thymocyte surface antigen G(IX)

For several reasons the G(IX) antigen (1) has a prominent place in current work on murine leukemia virus (MuLV): In the prototype G(IX+) mouse strain 129, the G(IX) trait is mendelian, and is expressed selectively (though not exclusively) on thymocytes. Thus, expression of this cell surface component is under the control of cellular genes and is subject to the controls governing the differentiation of T lymphocytes (2). Although the 129 mouse produces no demonstrable leukemia virus such as that found in the AKR strain, it was soon realized that G(IX) antigen must in some way be related to MuLV, because productive infection with MuLV is frequently associated with appearance of G(IX) antigen on cells that are genotypically G(IX-), most notably on MuLV-infected rat cells, or cells that belong to other differentiation pathways (1). The basis of this connection between G(IX) and MuLV has recently become clear from the demonstration that G(IX) is one of MuLV envelope. Therefore, our working hypothesis is that the presence of G(IX) is one of the antigens present on gp69/71 (3,4), the major glycoprotein component of the MuLV envelope. Therefore, our working hypothesis is that the presence of G(IX) antigen always denotes the presence of gp69/71 (though not all variants of gp69/71 need necessarily carry G(IX)). Study of the circumstances under which G(IX) is expressed on the cell surface is thus potentially a powerful approach to understanding how the expression of C-type viral genomes is controlled. Such studies are greatly facilitated by the availability of mutant and congenic strains of inbred mice which differ from the nonmutant or partner strains only with respect to one or another manifestation of the viral genome. It is for this reason that we record here (Table I) some details of two G(IX) mutant and two G(IX) congenic stocks derived in our colonies at Memorial Sloan-Kettering Cancer Center (MSKCC). In addition, to these four strains, Table I includes data for the three relevant partner strains, and for strain AKR, for comparison. These eight strains all differ from one another with respect to one or more MuLV-related traits.     

Plateletpheresis: comparison of platelet yields, processing time, and white cell content with two apheresis systems

Two apheresis systems (COBE Spectra and Fenwal CS-3000 Plus with TNX-6 chamber [CS-3000 Plus]) were compared by using their yield predictors and maximum processing times in regard to platelet yields and processing times (n = 200 each). Platelet yields (n = 50 each) and white cell (WBC) content (n = 20 each) from procedures using the current software revision (3.6) on the Spectra and various interface offset (IO) settings on the CS-3000 Plus were also compared. Significantly higher median platelet yields (4.88 [range, 1.84-9.97] vs. 4.57 [range, 2.82-9.20] × 10(11) platelets) and frequency of components with > or = 6.0 × 10(11) platelets (31.5 vs. 21.5%) were found with the Spectra. In the study with Spectra and the CS-3000 Plus IO settings, IO-10 and IO-13, overall, produced the most platelets, although the differences were not significant. All Spectra collections tested had < 5 × 10(8) WBCs, and, depending on the software revision, had either 85 percent (revision 3.6) or 100 percent (revision 2.5) of components with < 5 × 10(6) WBCs. To ensure that 100 percent of components contained < 5 × 10(8) WBCs when the CS-3000 Plus was used, IO settings of 10 or less were required, and to ensure components with < 5 × 10(6) WBCs, only IO-6 could be used. Spectra and CS-3000 Plus were capable of collecting large doses of platelets (up to the equivalent of 18 units) in processing times of 67 to 100 minutes with < 5 × 10(6) WBCs.     

Unusual kinetics of white cell clearance in transfused mice

BACKGROUND: Donor white cells (WBCs) in blood transfusions are responsible for complications in recipients, including alloimmunization, graft-versus-host disease (GVHD), and virus transmission and reactivation. The recent use of sequence-specific polymerase chain reaction assays to monitor the kinetics of clearance of donor WBCs in transfused humans and dogs found transient recirculation of donor lymphocytes on Days 3 to 5 after transfusion; this presumably reflected an abortive GVHD reaction to major histocompatibility complex-incompatible recipient cells, after which donor WBCs were cleared to undetectable levels. STUDY DESIGN AND METHODS: This study sought to develop a murine model to further characterize the kinetics and major histocompatibility complex restriction of donor WBC clearance. A sensitive murine Y chromosome- specific polymerase chain reaction assay was developed and applied to serial blood samples collected after transfusions of allogeneic blood to naive inbred, primed inbred, and outbred mice, as well as after transfusions of gamma-radiated blood to naive inbred mice. RESULTS: In inbred mice, both naive and primed to the allogeneic blood donor, transfused WBCs were not cleared to undetectable levels for more than 1 month after transfusion. Transfused outbred mice also showed prolonged donor WBC survival, although at lower levels than inbred mice. There was no evidence of GVHD in either inbred or outbred mice, and gamma radiation had no significant impact on donor WBC persistence. CONCLUSION: These results contrast with the rapid clearance of donor WBCs observed in humans and dogs. The immunologic basis for this discrepancy remains unclear. Caution should be exercised in any extrapolation to humans of conclusions drawn from results in transfused mice.     

Production of auto-anti-idiotypic antibody during the normal immune response to TNP-ficoll. I. Occurrence in AKR/J and BALB/c mice of hapten-augmentable, anti-TNP plaque-forming cells and their accelerated appearance in recipients of immune spleen cells

Attempts were made to elucidate the cause of the downward regulation of the splenic plaque-forming cell (PFC) response in AKR/J and BALB/c mice between days 4 and 7 after a single intravenous injection of 2,4,6,trinitrophenyl- lys-Ficoll(TNP-F). AKR/J spleen cells, taken 7 d after injection of TNP-F, were transferred, together with TNP-F, into normal AKR/J mice. The day-3 or – 4 PFC response of the recipients was much lower than that of recipients of normal cells. However, the suppression was only apparent because the presence of 10(-8)-10(-7) M 2,4,6-trinitrophenyl-ε-amino-n-caproic acid (TNP- EACA) (or 10(-7)-10(-6) M 2,4,-dinitrophenyl-ε-amino-n-caproic acid) in the PFC assay caused a dramatic increase in observed PFC, averaging 298 percent on day 3 and 122 percent on day 4. Recipients of normal cells showed no such hapten-augmentable PFC. T-depleted immune spleen cells did not cause any apparent suppression of the response to TNP-F, but hapten-augmentable PFC in recipient spleens were again prevalent. Suppression of the PFC response, as well as hapten-augmentable PFC, were seen after transfer of immune serum. It was postulated that hapten augmentation of PFC was caused by displacement of auto-anti-idiotypic antibody from the surface of blocked antibody- synthesizing cells. Further studies showed that such hapten-augmentable PFC occurred in the spleens of a large percentage of both AKR/J and BALB/c mice examined after day 4 of the primary response to TNP-F. Thus, it was hypothesized that the downward regulation of the magnitude and, possibly, also of the heterogeneity of the splenic-PFC response was due to an auto-antibody response to one or more major idiotypes of the anti-TNP response.     

A prospective analysis of staging laparoscopy in patients with primary and secondary hepatobiliary malignancies

Laparoscopy and laparoscopic ultrasound are used widely in cancer staging and are perceived to prevent unnecessary open exploration in many patients. The aim of this study was to analyze the impact of staging laparoscopy in improving resectability in patients with primary and secondary hepatobiliary malignancies. Over a 10-month period (November 1, 1997 to August 31, 1998), 186 patients with primary and secondary hepatobiliary cancers were submitted to operation for potentially curative resection. One hundred four patients staged laparoscopically (LAP) before laparotomy were compared prospectively to 82 patients undergoing exploration without laparoscopy (NO LAP). Assignment to each group was not random but was based on surgeon practice. Demographic data, diagnoses, the extent of preoperative evaluation, and the percentage of patients resected were similar in the two groups. Laparoscopy identified 26 (67%) of 39 patients with unresectable disease. In the NO LAP group, 28 patients (34%) had unresectable disease discovered at laparotomy. In patients with unresectable disease and submitted to biopsy only, the operating times were similar in the two groups (LAP 83 ±22 minutes vs. NO LAP 91 ±33 minutes; P = 0.4). However, laparoscopic staging significantly reduced the length of hospital stay (LAP 2.2 ±2 days vs. NO LAP 8.5 ±8.6 days; P = 0.006). Likewise, total hospital charges, normalized to 100 in the NO LAP patients, were significantly lower in the LAP group (LAP 54 ±42 vs. NO LAP 100 ±84; P = 0.02). Staging laparoscopy identified the majority of patients with unresectable hepatobiliary malignancies, significantly improved resectability, and reduced the number of days in the hospital and the total charges. The yield of laparoscopy was greatest for detecting peritoneal metastases (9 of 10), additional hepatic tumors (10 of 12), and unsuspected advanced cirrhosis (5 of 5) but often failed to identify nonresectability because of lymph node metastases, vascular involvement, or extensive biliary involvement. Eighty-three percent of patients subjected to laparotomy after laparoscopy underwent a potentially curative resection compared to 66% of those who were not staged laparoscopically. Supported in part by grants R01 CA76416 (Dr. Fong) and R01CA/DK80982 (Dr. Fong) from the National Institutes of Health. Presented at the Fortieth Annual Meeting of The Society for Surgery of the Alimentary Tract, Orlando, Fla., May 16–19, 1999.     

Genotoxicity of polar and apolar extracts obtained from Qualea multiflora and Qualea grandiflora

Ethnopharmacological relevance

The species Qualea grandiflora and Qualea multiflora, which belong to the Vochysiaceae family, are common in the Brazilian savannah (Cerrado biome), and the local inhabitants use these species to treat external ulcers and gastric diseases and as an anti-inflammatory agent. Studies have demonstrated that these plants contain compounds that exhibit pharmacological activities; however, the risks associated with their consumption are not known.

Material and methods

In the present study, the mutagenicity of polar and apolar extracts from Qualea grandiflora and Qualea multiflora were assessed by employing the Ames assay with and without metabolic activation. Additionally, phytochemical analyses (HPLC-ESI-IT-MS, HPLC-UV-PDA and GC-IT-MS) were performed to identify the chemical constituents present in these species, including the evaluation of physico-chemical properties, such as polarity or apolarity of the organic compounds, which are related to each fraction obtained. These studies provide important information regarding the biochemical behaviour of these compounds.

Results

All extracts exhibited mutagenicity, inducing frameshift mutations and base substitutions in DNA. Phytochemical analysis identified terpenes, ellagic acid derivatives and phytosteroids.

Conclusions

The mutagenicity observed might be due to the presence of pentacyclic triterpenes and polyphenols, which are able to generate reactive oxygen species (ROS) and result in the potential to cause DNA damage. The genetic risk identified in this present work shows that special attention should be considered for the use of compounds obtained from these plant species in medicinal treatments. Further studies must be conducted to identify safe therapeutic doses.