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Background and Objectives Transfusion-associated graft-versus-host disease (TA-GVHD) is a serious, potential complication of blood transfusion that is essentially prevented by blood product irradiation. Blood product irradiation is currently performed using gamma irradiation. X-ray irradiation is an alternative that has certain advantages: an X-ray irradiator is less expensive and does not have a radioactive source. However, the biochemical effects of X-ray irradiation on red blood cells (RBCs) have not been well characterized. The primary purpose of our study was to compare the effects of X-ray irradiation with gamma irradiation on RBC membrane permeability. A secondary purpose was to verify that X-ray irradiation has the same effect on lymphocytes as gamma irradiation. Materials and Methods Ten RBC units were split into two portions; five units of each were then irradiated with either gamma or X-ray at a dose of 35 Gy or 25 Gy, respectively. Free plasma haemoglobin and extracellular potassium levels were measured in each unit over time. Another unit was divided into three parts for lymphocyte studies; one part was not irradiated as a control and the other two received 25 Gy of irradiation via X-ray or gamma irradiation, respectively. Results Minimally increased free plasma haemoglobin was found only in X-ray-irradiated units after 25 Gy compared to gamma-irradiated units. However, extracellular potassium levels were not significantly different in these groups. Extracellular potassium levels were slightly higher only in gamma irradiated units at 35 Gy. X-ray and gamma irradiation were equivalent in affecting lymphocyte function. Conclusions Small differences in RBC membrane permeability are found between gamma-irradiated and X-ray-irradiated units. However, these differences are not likely to be clinically important.

Vaccination has been proposed for the prevention of disease due to enterohemorrhagic Escherichia coli (EHEC), but the immune response following human infection, including the choice of potential antigens, has not been well characterized. To study this, sera were obtained from five pediatric patients with acute diarrhea caused by E. coli O157:H7 0, 8, and 60 days after hospitalization. These sera were used to examine the immune response to four different EHEC virulence factors: Tir (translocated intimin receptor, which is inserted into the host cell membrane), intimin (bacterial outer membrane protein which binds to Tir), EspA (secreted protein which forms filamentous structures on EHEC surface), and EspB (inserted into the host membrane and cytoplasm). The response to O157:H7 lipopolysaccharide was also examined. Sera were assayed against purified recombinant proteins using immunoblot analysis and by enzyme-linked immunosorbent assay to determine the sera's titers to each of the antigens in all patients. We found that there was little reaction to EspA, EspB, and intimin in the acute-phase sera, although there was some reactivity to Tir. By day 8, titers of antibody to all four virulence factors were present in all patients, with a very strong response against Tir (up to a titer of 1:256,000), especially in hemolytic-uremic syndrome patients, and lesser strong responses to the other three antigens. The titer to the antigens 60 days after hospitalization was decreased but was still highest for Tir. These results suggest that there is a strong immune response to Tir, and to a lesser extent to the other three virulence factors, following EHEC disease, indicating that these bacterial molecules are potential vaccine candidates for preventing EHEC disease. They also suggest that bacterial virulence factors that are inserted into host cells during infection by type III secretion systems (Tir or EspB) are still recognized by the host immune response.

PURPOSE Curative therapy for multiple myeloma continues to be an elusive goal. This report discusses the Northern California Oncology Group (NCOG) phase I and II trial in high-tumor-burden disease that used a strategy that consisted of induction chemotherapy (vincristine, melphalan, cyclophosphamide, and prednisone [VMCP]) for eight cycles followed by sequential hemibody radiation therapy (RT) and subsequent chemotherapy for an additional eight cycles. PATIENTS AND METHODS Seventy-two previously untreated stage III myeloma patients were entered onto the study. Sixty-nine received induction chemotherapy, 40 received induction chemotherapy and hemibody RT, and 23 received induction chemotherapy, hemibody RT, and consolidative chemotherapy. RESULTS Twenty-two complete responses (CRs) were obtained by induction chemotherapy, with four additional CRs after RT and consolidative chemotherapy. Nineteen patients developed grade 4 hematologic toxicity primarily after upper hemibody RT. Eight of these developed long-standing neutropenia or thrombocytopenia. Median survival of the group was 134 weeks, which was not significantly different from other approaches. CONCLUSIONS Hemibody RT can be combined with chemotherapy as induction therapy and can be safely administered in a community setting. However, as administered here no survival advantage was demonstrated.

Background and Objectives Platelet function abnormalities have been reported in blood donors who have not consumed aspirin. Our objective was to identify factors other than aspirin that may contribute to impaired platelet function in qualified volunteer blood donors. Materials and Methods Blood samples were obtained from 24 donors following routine blood donation. Donors completed a study questionnaire that included questions about recent food consumption, medication and medical history. Platelet activation was measured using monoclonal antibodies and flow cytometry. CD62P expression and PAC-1 binding on platelets were used as indicators of platelet activation. Platelet function was measured on a platelet function analyser (PFA-100®) using both collagen/epinephrine (cEPI) and collagen/ADP (cADP) cartridges. Results Fifty-four per cent of donors (13 of 24) had normal platelet function. Thirty-eight per cent (nine of 24) had prolonged cEPI closure times, of whom four (17%) had no cEPI closure (> 300 seconds). No closure was associated with aspirin use (two donors) or chocolate consumption (two donors) before donation. Two donors (8%) had either a shortened cEPI or cADP closure time. Conclusions Platelet dysfunction in qualified blood donors is underestimated. Platelet function screening can identify donors with diet-related platelet dysfunction or with poor recollection of aspirin use.

A low-expression-class methicillin-resistant Staphylococcus aureus strain (strain 9302-2) was sent to 207 laboratories as part of the bacteriology component of the Laboratory Proficiency Testing Program of Ontario. An incorrect (susceptible) result was reported by 16 of 76 (21%) of laboratories that used the National Committee for Clinical Laboratory standards disk test, whereas 1 of 104 laboratories that used other methods reported an incorrect result (P < 0.05). Experiments showed discrepancies in the disk test results given by Mueller-Hinton agars from three manufacturers. We advise that laboratories should use a low expression-class methicillin-resistant S. aureus isolate as a control for the National Committee for Clinical Laboratory Standards disk test.

Flow cytometry assays, which measure CD69 activation and intracellular cytokine production, have been used to measure peripheral blood lymphocyte (PBL) responses to in vitro antigen exposure. In the present study, we show that, in healthy individuals and immunosuppressed kidney transplant recipients, CD69 expression and intracellular cytokine production by peripheral blood T cells compare favorably to thymidine uptake as a measure of PBL response to alloantigen in mixed leukocyte culture (MLC). Heparinized whole blood from 23 healthy individuals was incubated for 24-48 h with 3rd party allogeneic monocytes; blood from twelve kidney transplant recipients was incubated with monocytes from their kidney donor and with monocytes from unrelated individuals. The percentage of T cells expressing surface CD69 or intracellular IL-2 or IL-4 was determined by 3-color flow cytometry. We identified 5 donor-specific response patterns in our kidney transplant group. One transplant recipient was hyporesponsive; his cells did not express CD69 or produce IL-2 in response to either donor or 3rd party allogeneic cells. All other transplant recipients expressed CD69 and IL-2 in response to 3rd party allogeneic cells. Two had no response to donor cells (donor-specific hyporesponsiveness), three had donor-specific anergy (CD69 expression without cytokine production in response to donor cells), five had a donor-specific Thl response (CD69 expression and IL-2 production in response to donor cells), and one had a donor-specific Th2 response (CD69 expression and IL-4 but not IL-2 production in response to donor cells). Rapid measures of donor-specific hyporesponsiveness such as CD69 activation antigen expression and intracellular cytokine production may prove valuable in monitoring lymphocyte function and aid in the long-term management of kidney transplant recipients.

Our group has a long standing interest in the immune abnormalities present in patients with multiple myeloma. In particular the poor primary immune response to new antigen challenges exemplified by recurrent upper respiratory infections. This aberrant physiology has an in vitro correlate of diminished levels of serum immunoglobulins other than the monoclonal protein which marks the expression of the plasma cell tumor. Attempts to define the mechanisms of this immunodeficiency traditionally use the manipulation of production of immunoglobulins by peripheral blood mononuclear cells stimulated by pokeweed mitogen (PWM). In this system the inhibition of Ig production by added cell populations or culture supernatants is determined. Recently the use of Staphylococcal Aureus protein (SAC) as a stimulant proved a satisfactory system as well.

We report the results of a province-wide quality control program in which five methicillin-resistant Staphylococcus aureus strains were circulated to all Ontario laboratories (hospital, private, and public health laboratories) on nine occasions between 1980 and 1989. The level of expression of methicillin resistance in each of the isolates was determined by performing viable colony counts on serial dilutions of methicillin in agar, and each isolate was assigned to an expression class according to previous published criteria (A. Tomasz, S. Nachman, and H. Leaf, Antimicrob. Agents Chemother. 35:124-129, 1991). Over this time there was an improvement in the performance of laboratories in the recognition of three strains that were relatively easy to detect (strains B, C, and E). These strains were of expression class II, and 98% of laboratories reported correct identifications in 1986. Performance in identifying two strains (strains A and D) of expression class I remained poor. Strain A was circulated in two surveys in 1987 and 1989, and laboratories were sent a questionnaire requesting details of the methods used in those two surveys. The methods used by the laboratories were classified into three categories: disk diffusion, single-plate screening by agar incorporation, and automated methods, which included premanufactured MIC panels. Between the 1987 and 1989 surveys, there was no change in the performance of the disk diffusion test (60% correct on both occasions), but there was improvement in the sensitivity of the agar incorporation test (36% correct in 1987 and 84% correct in 1989) and in automated methods (43% correct in 1987 and 79% correct in 1989). Over a decade, there was overall improvement in the performance of laboratories in detecting easy-to-detect strains, but there were difficulties in detecting organisms of low expression class, and an organism of very low expression class should be designated as a control organism for routine testing of methicillin-resistant s. aureus isolates.

Antisera made to prototype serogroup B strains of Neisseria meningitidis were used to serotype, by agar gel double diffusion, 262 meningococcal serogroups B and C strains isolated in Canada. The strains included 93 from patients and 169 from carriers. Serotype 2 was associated with 39 of 75 (52%) of group B strains and 14 of 18 (77.8%) of group C strains isolated from patients. The group B strains were mainly (87.2%) serotype 2b, while the majority (92.2%) of group C strains was serotype 2a. Other serotypes (including a new provisional serotype) represented 25.3 and 5.5% of groups B and C strains, respectively. The new serotype accounted for 13% of the group B strains. Approximately 23% of the strains isolated from patients were nontypable. The distribution of serotype 2, nontype 2 (other serotypes), and nontypable strains isolated from carriers was 2.1, 36.6, and 61.3%, respectively, for group B meningococci and 22.2, 29.6, and 48.2%, respectively, for group C meningococci. Serotype 11 was the most prominent of the strains isolated from carriers. Approximately 7% of all the strains were multiple serotypes. Serotype 2 is an important virulence marker associated with meningococcal groups B and C disease in Canada, with serotypes 2a and 2b being markedly associated with groups C and B meningococcal disease, respectively.

A patient is described who suffered from severe chronic asthma complicated by repeated chest infections. She developed a large gelatinous pseudotumour of the lung which was found to be caused by Bacillus sphaericus.

Enrichment culture with a semisolid medium increased by 6% the isolation rate of Campylobacter fetus subsp. jejuni. The semisolid enrichment medium was also used successfully as a transport medium for Campylobacter isolates. A blood agar plate streaked with Pseudomonas aeruginosa, Clostridium perfringens, and a laboratory strain of Campylobacter was a good control system for the microaerophilic atmosphere. Good growth of all three organisms indicated satisfactory conditions for culturing Campylobacter.

Campylobacter jejuni Skirrow biotype 1, Lior serotype 8 was isolated from the appendix of an 11-year-old boy who had a 6-h history of acute abdominal pain. Histological diagnosis on the appendix section was early acute appendicitis. Dilute carbol fuchsin stain and indirect fluorescent antibody test performed on the appendix section also revealed the presence of Campylobacter sp. The patient developed a significant bactericidal antibody titer of 1,024, providing substantial clinical evidence of the pathogenicity of the isolate. This case indicated that not only may abdominal pain caused by Campylobacter enteritis mimic appendicitis, but the organism may actually be recovered from the infected appendix.

Enrichment media for isolation of therm0Philic campylobacters from stools include alkaline peptone water (1), Campy-thio (2), nutrient broth (3), semi-solid motility test medium (4), and bmcella broth (5). Campy-thio has been widely accepted in the United States and is now available commercially (BBL Microbiology Systems, USA). Our experience with a semi. solid enrichment medium indicated that it had a higher isolation rate than Campy-thio. Since a parallel study of the two media has not yet been reported, we investigated the value of enrichment culture for isolation of campylobacter from contacts of patients with eampylobacter enteritis, comparing the performance of two primary selective media and three enrichment methods.

Microorganisms may be resistant to antibiotics by one of four basic mechanisms: 1) they may synthesize enzymes that inactivate antibiotics; 2) target sites on the microorganisms may be resistant to antibiotic binding; 3) they may become resistant to particular antibiotics by the development of metabolic pathways which bypass the site of the antibiotic’s action; 4) they may modify their inner or outer membrane to prevent the penetration of the antibiotic to the microbial target site.

SUMMARY: The effects of intranasal inoculation of mice more than 6 weeks old with the TE 55 strain of trachoma virus were studied. The histology and course of the pulmonary lesions produced are described. Infected mice showed a poor response of complement-fixing antibodies after infection. Precipitating antigens were detected in infected mouse lungs.

The antiviral effect of 5% idoxuridine in dimethyl sulphoxide intermittently applied and of 40% idoxuridine in dimethyl sulphoxide continuously applied for four days to the lesions in patients with zoster of recent onset was studied in two double-blind controlled trials. Most, but not all, of the patients receiving intermittent active treatment had pain for a short period only. The effect of continuous treatment was striking: pain had disappeared within nine days in all the patients and healing was accelerated. The results were statistically significant.