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3. Candidaemia with uncommon Candida species: Predisposing factors, outcome, antifungal susceptibility, and implications for management.

Author

McBride J., Chen S.C.A., Marriott D., Playford E.G., Nguyen Q., Ellis D., Meyer W., Sorrell T.C., Slavin M., McCormack J., Walmsley K., Looke D., Johnson B., Nimmo G., Playford G., Drummond D., Forgan Smith R., Preston E., Allworth A., Faoagali J., Gerns N., Botes J., Cherian S., Robson J., Vohra R., Norton R., Coulter C., O'Kane G., Robb D., Gottlieb T., Chambers I., DeWit D., Carroll M., Dobson P., Ferguson J., Tierney L., Jozwiak F., Munro R., Tomasotos V., Pickles R., Holland J., Groenwad F., Hale K., Watson M., Vaz R., Hardiman R., Baleriola C., Ryan S., Pritchard R., Weeks K., Benn R., Lawrence R., Taylor P., Lindstrom S., Harkness J., Palasanthrian P., Grant R., McPetrie R., Johnson R., Halliday C., Maszewska K., Dennis N., Newton P., Franklin C., Morrisey O., Spelman D., Wesselingh S., Speed B., Hellsten J., Mayall B., Russell J., Broughton S., Woolley I., Coloe S., Sherman A., Korman T., Graves S., Huysmans M., Gordon D., Rowlands K., Shaw D., Ritchie B., Handkle R., Beaman M., Chiam A., McCarthy J., Heath C., Altmann S., Arthur I., Speers D., Cox E., Cooley L., McGregor A., Currie B., Lum G., Fisher D., Collignon P., Roberts J., Watson A., McBride J., Chen S.C.A., Marriott D., Playford E.G., Nguyen Q., Ellis D., Meyer W., Sorrell T.C., Slavin M., McCormack J., Walmsley K., Looke D., Johnson B., Nimmo G., Playford G., Drummond D., Forgan Smith R., Preston E., Allworth A., Faoagali J., Gerns N., Botes J., Cherian S., Robson J., Vohra R., Norton R., Coulter C., O'Kane G., Robb D., Gottlieb T., Chambers I., DeWit D., Carroll M., Dobson P., Ferguson J., Tierney L., Jozwiak F., Munro R., Tomasotos V., Pickles R., Holland J., Groenwad F., Hale K., Watson M., Vaz R., Hardiman R., Baleriola C., Ryan S., Pritchard R., Weeks K., Benn R., Lawrence R., Taylor P., Lindstrom S., Harkness J., Palasanthrian P., Grant R., McPetrie R., Johnson R., Halliday C., Maszewska K., Dennis N., Newton P., Franklin C., Morrisey O., Spelman D., Wesselingh S., Speed B., Hellsten J., Mayall B., Russell J., Broughton S., Woolley I., Coloe S., Sherman A., Korman T., Graves S., Huysmans M., Gordon D., Rowlands K., Shaw D., Ritchie B., Handkle R., Beaman M., Chiam A., McCarthy J., Heath C., Altmann S., Arthur I., Speers D., Cox E., Cooley L., McGregor A., Currie B., Lum G., Fisher D., Collignon P., Roberts J., and Watson A.

Abstract

The risk factors for and clinical features of bloodstream infection with uncommon Candida spp. (species other than C. albicans, C. glabrata, C. parapsilosis, C. tropicals and C. krusei) are incompletely defined. To identify clinical variables associated with these species that might guide management, 57 cases of candidaemia resulting from uncommon Candida spp. were analysed in comparison with 517 episodes of Candida albicans candidaemia (2001-2004). Infection with uncommon Candida spp. (5.3% of candidaemia cases), as compared with C. albicans candidaemia, was significantly more likely to be outpatient-acquired than inpatient-acquired (15 of 57 vs. 65 of 517 episodes, p0.01). Prior exposure to fluconazole was uncommon (n =1). Candida dubliniensis was the commonest species (n =22, 39%), followed by Candida guilliermondii (n = 11, 19%) and Candida lusitaniae (n = 7, 12%). C. dubliniensis candidaemia was independently associated with recent intravenous drug use (p0.01) and chronic liver disease (p0.03), and infection with species other than C. dubliniensis was independently associated with age <65 years (p0.02), male sex (p0.03) and human immunodeficiency virus infection (p0.05). Presence of sepsis at diagnosis and crude 30-day mortality rates were similar for C. dubliniensis-related, non- C. dubliniensis-related and C. albicans-related candidaemia. Haematological malignancy was the commonest predisposing factor in C. guilliermondii (n = 3, 27%) and C. lusitaniae (n = 3, 43%) candidaemia. The 30-day mortality rate of C. lusitaniae candidaemia was higher than the overall death rate for all uncommon Candida spp. (42.9% vs. 25%, not significant). All isolates were susceptible to amphotericin.B, voriconazole, posaconazole, and caspofungin; five strains (9%) had fluconazole MIC values of 16-32 mg/L. Candidaemia due to uncommon Candida spp. is emerging among hospital outpatients; certain clinical variables may assist in recognition of this entity. © 2009 The Authors Journal c

Published
2012

4. Active surveillance for candidemia, Australia.

Author

Watson M., Walmsley K., Looke D., Johnson B., Nimmo G., Drummond D., Forgan-Smith R., Preston E., Allworth A., Faoagali J., Gerns N., Botes J., Cherian S., Robson J., Vohra R., Norton R., O'Kane G., Robb D., Gottlieb T., Chambers I., DeWit D., Carroll M., Dobson P., Ferguson J., Tierney L., Jozwiak F., Munro R., Tomasotos V., Pickles R., Holland J., Groenwald F., Hale K., Vaz R., Hardiman R., Baleriola C., Ryan S., Pritchard R., Weeks K., Benn R., Adams N., Lawrence R., Taylor P., Lindstrom S., Harkness J., Palasanthrian P., Grant R., McPetrie R., Johnson R., Halliday C., Maszewska K., Lee O.C., Meyer W., Dennis N., Newton P., Franklin C., Morrisey O., Spelman D., Wesselingh S., Speed B., Hellsten J., Mayall B., Russell J., Broughton S., Woolley I., Coloe S., Korman T., Graves S., Huysmans M., Sherman A., Gordon D., Rowlands K., Shaw D., Ferguson W., Ritchie B., Handke R., Beaman M., Chiam A., McCarthy J., Heath C., Altmann S., Arthur I., Speers D., Cox E., Cooley L., McGregor A., Currie B., Lum G., Fisher D., McBride J., Chen S., Slavin M., Nguyen Q., Marriott D., Playford E.G., Ellis D., Sorrell T., Coulter C., McCormack J., Watson M., Walmsley K., Looke D., Johnson B., Nimmo G., Drummond D., Forgan-Smith R., Preston E., Allworth A., Faoagali J., Gerns N., Botes J., Cherian S., Robson J., Vohra R., Norton R., O'Kane G., Robb D., Gottlieb T., Chambers I., DeWit D., Carroll M., Dobson P., Ferguson J., Tierney L., Jozwiak F., Munro R., Tomasotos V., Pickles R., Holland J., Groenwald F., Hale K., Vaz R., Hardiman R., Baleriola C., Ryan S., Pritchard R., Weeks K., Benn R., Adams N., Lawrence R., Taylor P., Lindstrom S., Harkness J., Palasanthrian P., Grant R., McPetrie R., Johnson R., Halliday C., Maszewska K., Lee O.C., Meyer W., Dennis N., Newton P., Franklin C., Morrisey O., Spelman D., Wesselingh S., Speed B., Hellsten J., Mayall B., Russell J., Broughton S., Woolley I., Coloe S., Korman T., Graves S., Huysmans M., Sherman A., Gordon D., Rowlands K., Shaw D., Ferguson W., Ritchie B., Handke R., Beaman M., Chiam A., McCarthy J., Heath C., Altmann S., Arthur I., Speers D., Cox E., Cooley L., McGregor A., Currie B., Lum G., Fisher D., McBride J., Chen S., Slavin M., Nguyen Q., Marriott D., Playford E.G., Ellis D., Sorrell T., Coulter C., and McCormack J.

Abstract

Population-based surveillance for candidemia in Australia from 2001 to 2004 identified 1,095 cases. Annual overall and hospital-specific incidences were 1.81/100,000 and 0.21/1,000 separations (completed admissions), respectively. Predisposing factors included malignancy (32.1%), indwelling vascular catheters (72.6%), use of antimicrobial agents (77%), and surgery (37.1%). Of 919 episodes, 81.5% were inpatient healthcare associated (IHCA), 11.6% were outpatient healthcare associated (OHCA), and 6.9% were community acquired (CA). Concomitant illnesses and risk factors were similar in IHCA and OHCA candidemia. IHCA candidemia was associated with sepsis at diagnosis (p<0.001), death <=30 days after infection (p<0.001), and prolonged hospital admission (p<0.001). Non-Candida albicans species (52.7%) caused 60.5% of cases acquired outside hospitals and 49.9% of IHCA candidemia (p = 0.02). The 30-day death rate was 27.7% in those >=65 years of age. Adult critical care stay, sepsis syndrome, and corticosteroid therapy were associated with the greatest risk for death. Systematic epidemiologic studies that use standardized definitions for IHCA, OHCA, and CA candidemia are indicated.

Published
2012

5. Risk factors for new detection of vancomycin-resistant enterococci in acute-care hospitals that employ strict infection control procedures.

Author

Olden D., Franklin C., Pearson S., Padiglione A.A., Wolfe R., Grabsch E.A., Grayson M.L., Johnson P.D.R., Mayall B., Spelman D., Olden D., Franklin C., Pearson S., Padiglione A.A., Wolfe R., Grabsch E.A., Grayson M.L., Johnson P.D.R., Mayall B., and Spelman D.

Abstract

Accurate assessment of the risk factors for colonization with vancomycin-resistant enterococci (VRE) among high-risk patients is often confounded by nosocomial VRE transmission. We undertook a 15-month prospective cohort study of adults admitted to high-risk units (hematology, renal, transplant, and intensive care) in three teaching hospitals that used identical strict infection control and isolation procedures for VRE to minimize nosocomial spread. Rectal swab specimens for culture were regularly obtained, and the results were compared with patient demographic factors and antibiotic exposure data. Compliance with screening was defined as "optimal" (100% compliance) or "acceptable" (minor protocol violations were allowed, but a negative rectal swab specimen culture was required within 1 week of becoming colonized with VRE). Colonization with VRE was detected in 1.56% (66 of 4,215) of admissions (0.45% at admission and 0.83% after admission; the acquisition time was uncertain for 0.28%), representing 1.91% of patients. No patients developed infection with VRE. The subsequent rate of new acquisition of VRE was 1.4/1,000 patient days. Renal units had the highest rate (3.23/1,000 patient days; 95% confidence interval [CI], 1.54 to 6.77/1,000 patient days). vanB Enterococcus faecium was the most common species (71%), but other species included vanB Enterococcusfaecalis (21%), vana E. faecium (6%), and vana E. faecalis (2%). The majority of isolates were nonclonal by pulsed-field gel electrophoresis analysis. Multivariate analysis of risk factors in patients with an acceptable screening suggested that being managed by a renal unit (hazard ratio [HR] compared to the results for patients managed in an intensive care unit, 4.6; 95% CI, 1.2 to 17.0 [P = 0.02]) and recent administration of either ticarcillin-clavulanic acid (HR, 3.6; 95% CI, 1.1 to 11.6 [P = 0.03]) or carbapenems (HR, 2.8; 95% CI, 1.0, 8.0 [P = 0.05]), but not vancomycin or broad-spectrum cephalosporins, were

Published
2012

6. Acquired bloodstream infection in the ICU: Microbiological diagnosis and mortality.

Author

Tony K.M., Bellomo R., Hart G.K., Mayall B., Johnson P.D., Prowle J.R., Echeverri J.E., Ligabo E.V., Taori G.C., Crozier T.M., Tony K.M., Bellomo R., Hart G.K., Mayall B., Johnson P.D., Prowle J.R., Echeverri J.E., Ligabo E.V., Taori G.C., and Crozier T.M.

Abstract

INTRODUCTION. Acquired bloodstream infection (BSI) is though to be associated with increased morbidity and mortality in ICU patients [1]. However, the clinical significance of BSI is likely to vary with microbiological diagnosis [1] and the relative incidences of different infections are likely to vary between differing clinical environments [2]. OBJECTIVES. To examined the frequency and classification of ICU-acquired BSI and their effect on hospital mortality in two Australian teaching hospitals. METHODS. All ICU admissions of>72 h were considered. Data were available from 1998-2009 in one centre and 2003-2009 in the other. Baseline demographics, admission illness severity and co-morbidity data were obtained from ICU admission databases. Microbiological diagnoses were obtained from pathology department electronic records. Survival was defined by hospital discharge or status at 90 days. ICU-acquired BSI was defined by a positive blood culture taken after day 3 in ICU; two cultures were required in the case of saprophytic skin commensals. RESULTS. We identified 6339 ICU admissions lasting>72 h. 330 of these were complicated by BSI, and in 44 admissions>1 species was isolated during the course of the ICU stay. For statistical analysis pathogens were categorised into taxonomic groups. Five groups accounted for 94% of novel microbiological isolates. The effect of BSIs on subsequent survival from the time of diagnosis was examined in a Cox proportional-hazard analysis controlling for baseline demographics and admission illness severity. (Table presented). CONCLUSIONS. Only bloodstream infection with S. aureus, Gram -ve Bacilli and Candida were statistically associated with death. S. aureus and Gram-ve BSI occurred equally frequently and appear equally adverse. Collectively these three forms of BSI complicated fewer than 4% of ICUadmissions.Thus,while important on an individual basis, their impact on survival in the entire cohort is small. In this ICU population, interven

Published
2010

7. SMART-COP: A tool for predicting the need for intensive respiratory or vasopressor support in community-acquired pneumonia.

Author

Ramirez J.A., Looke D., Garske L., Playford G., Spelman D., Kotsimbos T., Heath C., Catton M., Birch C., Druce J., Ryan N., Irving L., Hart D., Bardin P., Charles P., Wolfe R., Whitby M., Fine M.J., Fuller A., Stirling R., Wright A., Christiansen K., Waterer G., Pierce R., Armstrong J., Korman T.M., Holmes P., Obrosky D.S., Peyrani P., Johnson P., Hooy M., Grayson L., Mayall B., Nimmo G., Munckhof W., Ramirez J.A., Looke D., Garske L., Playford G., Spelman D., Kotsimbos T., Heath C., Catton M., Birch C., Druce J., Ryan N., Irving L., Hart D., Bardin P., Charles P., Wolfe R., Whitby M., Fine M.J., Fuller A., Stirling R., Wright A., Christiansen K., Waterer G., Pierce R., Armstrong J., Korman T.M., Holmes P., Obrosky D.S., Peyrani P., Johnson P., Hooy M., Grayson L., Mayall B., Nimmo G., and Munckhof W.

Abstract

Background. Existing severity assessment tools, such as the pneumonia severity index (PSI) and CURB-65 (tool based on confusion, urea level, respiratory rate, blood pressure, and age >=65 years), predict 30-day mortality in community-acquired pneumonia (CAP) and have limited ability to predict which patients will require intensive respiratory or vasopressor support (IRVS). Methods. The Australian CAP Study (ACAPS) was a prospective study of 882 episodes in which each patient had a detailed assessment of severity features, etiology, and treatment outcomes. Multivariate logistic regression was performed to identify features at initial assessment that were associated with receipt of IRVS. These results were converted into a simple points-based severity tool that was validated in 5 external databases, totaling 7464 patients. Results. In ACAPS, 10.3% of patients received IRVS, and the 30-day mortality rate was 5.7%. The features statistically significantly associated with receipt of IRVS were low systolic blood pressure (2 points), multilobar chest radiography involvement (1 point), low albumin level (1 point), high respiratory rate (1 point), tachycardia (1 point), confusion (1 point), poor oxygenation (2 points), and low arterial pH (2 points): SMART-COP. A SMART-COP score of >=3 points identified 92% of patients who received IRVS, including 84% of patients who did not need immediate admission to the intensive care unit. Accuracy was also high in the 5 validation databases. Sensitivities of PSI and CURB-65 for identifying the need for IRVS were 74% and 39%, respectively. Conclusions. SMART-COP is a simple, practical clinical tool for accurately predicting the need for IRVS that is likely to assist clinicians in determining CAP severity. © 2008 by the Infectious Diseases Society of America. All rights reserved.

Published
2008

18. Response

Author

AXELSSON, K., primary, LJUNG, B.-M. E., additional, CHEW, K. L., additional, MAYALL, B. H., additional, MOORE, D. H., additional, SMITH, H. S., additional, THOR, A. D., additional, and EDGERTON, S. M, additional

Published
1995
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27. Nuclear DNA analysis of oral hyperplasia and dysplasia using image cytometry.

Author

Abdel-Salam, M., Mayall, B. H., Hansen, L. S., Chew, K. L., and Greenspan, J. S.

Subjects
*DNA, *HYPERPLASIA, *DYSPLASIA, *CYTOMETRY
Abstract

We investigated the value of image analysis in discriminating among oral white lesions with hyperplasia without dysplasia and oral white or white-and-red lesions with moderate or severe dysplasia. Normal oral epithelial tissue was used as a control. Image analysis was applied to 5 μm formalin-fixed sections stained with the azure A-Feulgen reaction for neuclear DNA. For 150-200 cells from each section, 5 neuclear variable were assessed: area, form factor,total stain, average stain and ellipticity. For each variable, 2 measurements were obtained, the mean and the interquartile range, and were used for stepwise discriminant analsysis. Using this test, a model of 3 measurements with the most discriminanting power was developed. When the jackknife classification test was applied to this model, we could discriminate with 81% accuracy between the 4 groups of tissue studied. [ABSTRACT FROM AUTHOR]

Published
1987
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28. Health visitors as educators.

Author

Foster M and Mayall B

Subjects
*CHILDREN'S health, *HEALTH education, *MEDICAL personnel, *PARENTS
Abstract

This paper describes some models of health education as a context for considering data from a recent study of mothers' and health visitors' perspectives on good child health care. Most health visitors favoured an individualistic topdown approach aimed at changing mothers' behaviour. Mothers preferred a dialogue which started from their own priorities. [ABSTRACT FROM AUTHOR]

Published
1990
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29. One big rush: dinner-time at school.

Author

Turner S, Mayall B, and Mauthner M

Abstract

The qualitative study described in this paper considers the social context of school meals in an urban primary school in southern England. The study was designed to provide information about the factors affecting children's food consumption, the contexts in which food is eaten in school and children's views on how food eaten at school contributes to their diet. Data were collected using a range of methods including participant observation. The findings suggest that for many children eating school dinners is a rushed and stressful occasion rather than a pleasant social experience. Children lack control over menus and may receive meals that are inadequate in quantity and variety. Children's experience of eating is rarely related to teaching and learning about food in the classroom. [ABSTRACT FROM AUTHOR]

Published
1995

34. Prospective Comparison of the Clinical Impacts of Heterogeneous Vancomycin-Intermediate Methicillin-Resistant Staphylococcus aureus(MRSA) and Vancomycin-Susceptible MRSA

Author

Horne, K. C., Howden, B. P., Grabsch, E. A., Graham, M., Ward, P. B., Xie, S., Mayall, B. C., Johnson, P. D. R., and Grayson, M. L.

Abstract

ABSTRACTAlthough methicillin (meticillin)-resistant Staphylococcus aureus(MRSA) strains with reduced susceptibility to vancomycin (RVS-MRSA; including vancomycin-intermediate S. aureus[VISA] and heterogeneous VISA [hVISA]) have been linked with vancomycin treatment failure, it is unclear whether they are more pathogenic than vancomycin-susceptible MRSA (VS-MRSA). We prospectively assessed patients with clinical MRSA isolates during a 10-month period to determine clinical status (infection versus colonization) and therapeutic outcome before correlating these findings with the results of detailed in vitro assessment of vancomycin susceptibility, including population analysis profile (PAP) testing. hVISA and VISA were defined by standard PAP criteria (area-under-the-curve ratio compared to that of the reference hVISA strain Mu3 [≥0.9]) and routine CLSI criteria (vancomycin MIC, 4 to 8 μg/ml), respectively. Among the 117 patients assessed, 58 had RVS-MRSA isolates (56 hVISA and 2 VISA) and 59 had VS-MRSA isolates; the patient demographics and comorbidities were similar. RVS-MRSA was associated with a lower rate of infection than VS-MRSA (29/58 versus 46/59; P= 0.003), including a lower rate of bacteremia (3/58 versus 20/59, respectively; P< 0.001). The cure rates in RVS-MRSA and VS-MRSA groups were not statistically different (16/26 versus 31/42; P= 0.43), but the post hoc assessment of treatment regimes and study size made detailed conclusions difficult. The results of the macro method Etest correlated well with the PAP results (sensitivity, 98.3%, and specificity, 91.5%), but broth microdilution and our preliminary RVS-MRSA detection method correlated poorly. All isolates were susceptible to linezolid and daptomycin. These data suggest that detailed prospective laboratory identification of RVS-MRSA isolates may be of limited value and that, instead, such in vitro investigation should be reserved for isolates from patients who are failing appropriate anti-MRSA therapy.

Published
2009
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36. Purification of the chromosomes of the Indian muntjac by flow sorting.

Author

Carrano, A V, Gray, J W, Moore, D H, Minkler, J L, Mayall, B H, van Dilla, M A, and Mendelsohn, M L

Abstract

Metaphase chromosomes were isolated from a male Indian muntjac cell line, were stained with ethidium bromide and were analyzed by flow microfluorometry to establish a deoxyribonucleic acid (DNA)-based karyotype. Five major peaks were evident on the chromosomal DNA distribution corresponding to the five chromosome types in this species. The amount of DNA in each chromosome was confirmed by cytophotometric measurements of intact metaphase spreads. The five chromosome types were separated by flow sorting at rates up to several hundred chromosomes per second. The sorted chromosomes were identified by morphology and by Giemsa banding patterns. The automsomes, Numbers 1, 2 and 3, and the X + 3 composite chromosome were separated with a high degree of purity (90%). The centromere region of the X + 3 chromosome was fragile to mechanical shearing, and during isolation a small proportion of these chromosomes broke into four segiments: the long arm, the short arm, the short arm plus centromere and the centromere region. A large fraction of the constitutive heterochromatin of this species is present in the centromere region of the X + 3 chromosome and in the Y chromosome; these two regions possess similar amounts of DNA and therefore sort together. Chromosome flow sorting is rapid, reproducible and precise; it allows the collection of microgram quantities of purified chromosomes.

Published
1976
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38. Interactive display and analysis of data from bivariate flow cytometers.

Author

Bennett, D E and Mayall, B H

Abstract

An interactive computer program, SWELL, displayss and analyzes bivariate distributions generated by flow cytometers. SWELL is modular with options available via a menu, is written in Fortran, and utilizes a video color display system. Data are accumulated as a bivariate distribution that is transferred to the computer as a 64 x 64 matrix. For ease of visualization, matrices are displayed in pseudocolor. The distribution values are broken into eight ranges and each range is represented by a color. Each element of the matrix is then displayed in its assigned color. To allow pooling and comparison, distributions are aligned, edited, and standardized. Unknown samples are pooled or analyzed singly and compared to the normal pool by subtraction. Differences are displayed as pseudocolor matrices of sign, magnitude, or statistical magnitude in units of standard deviation. This latter display, scaled to tolerance limits, readily reveals regions of significant difference between normal and abnormal samples. Counts within such regions can be compared to diagnose samples automatically.

Published
1979
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39. Flow cytometry of human gynecologic specimens using log chromomycin A3 fluorescence and log 90 degrees light scatter.

Author

Barrett, D L, Jensen, R H, King, E B, Dean, P N, and Mayall, B H

Abstract

Flow cytometry and electronic cell sorting are being investigated to screen gynecologic specimens for cervical neoplasia. Cellular DNA content is quantitated by Chromomycin A3 fluorescence and cell size is quantitated by 90 degrees light scatter; the logarithms of the measured intensities are used to produce a two parameter histogram. To determine the cell types responsible for signals in various histogram regions, systematic electronic cell sorting is performed. The sorted fractions are sedimented into microscope slides and stained by the Papanicolaou technique. The cells in each fraction are identified by conventional cytomorphologic criteria. Morphologic analysis of sorted cells reveals histogram regions corresponding to specific cell types. One very important region contains the highest concentration of signals from abnormal cells and is therefore the best region to analyze for specimen abnormality. However, because a significant number of signals in this region are from normal cells, specimens cannot be diagnosed by their analysis. Another important histogram region is composed primarily of signals from endocervical columnar and metaplastic cells. The presence of such cells is a good criterion for specimen adequacy, therefore analysis of signals in this region is essential to assess specimen adequacy for automatic screening.

Published
1979
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40. Strategies for choosing a deoxyribonucleic acid stain for flow cytometry of metaphase chromosomes.

Author

Jensen, R H, Langlois, R G, and Mayall, B H

Abstract

Requirements for flow cytometry of metaphase chromosomes stained with three deoxyribonucleic acid (DNA)-specific fluorescent dyes--Hoechst 33258, Chromomycin A3, and ethidium bromide--are reviewed. Fluorescence properties of these three stains when bound to mitotic cells or to chromosomes in suspension are measured and compared with fluorescence properties when bound to DNA in solution. Conditions are given for high resolution flow cytometry of Chinese hamster chromosomes stained with each of the fluorophors, and histograms are presented that exhibit differences in relative peak position and area. Energy transfer fluorescence between two DNA stains is presented as a potentially useful new parameter for flow cytometry of chromosomes and is illustrated by fluorescence energy transfer from Chromomycin A3 to ethidium bromide when simultaneously bound to hamster mitotic cells.

Published
1977
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41. Tetraploid-Diploid Mosaicism in a Surviving Infant

Author

Kohn, Gertrude, Mayall, B H, Miller, M E, and Mellman, W J

Abstract

Extract: Although tetraploidy and tetraploid-diploid mosaicism has been well documented in studies of aborted human fetuses, no living case has been reported. This report concerns a male infant with tetraploid-diploid mosaicism who survived for 36 weeks. Because the peripheral blood cells of this infant displayed gross differences both in cell size and in DNA content, it was possible to establish that the tetraploidy observed in cultured cells was a true reflection of in vivo mosaicism.The propositus was born on December 6, 1965, after a 42-week gestation notable for a paucity of fetal movement. Birth weight was 1.7 kg, length 40.6 cm and head circumference 25.4 cm. He presented with multiple congenital anomalies. Peripheral blood smears appeared to contain two populations of neutrophilic granulocytes that differed in overall size.Immunological assessment gave the following results : 1. Serum immunoelectrophoresis performed at the ages of 4, 10 and 14 weeks showed qualitatively normal immunoglobulins. 2. Normal antibody responses were obtained to type I polio and to typhoid-paratyphoid vaccines given at age 10 weeks. 3. Normal delayed hypersensitivity was obtained following stimulation with 2,4-dinitrofluorobenzene at the age of 12 weeks. There was a normal plasma growth hormone response to insulin-induced hypoglycemia at 12 weeks of age.Many of the cells in follicular centers of the spleen and lymph nodes were pale, and the lymphocytes surrounding them were bizarre, being unusually large and hyperchromatic. The histologic architecture was preserved and cortico-medullary differentiation maintained.Tetraploid-diploid mosaicism was found in ten short-term cultures of peripheral blood leukocytes obtained over a seven-month period. The average proportion of tetraploid cells was 69 % (range 64 to 77 %).Chromosomal analysis of six different primary fibroblast cultures, including that derived from the postmortem lung, were diploid in number and euploid in karyotype.Peripheral blood smears appeared to have two populations of neutrophilic granulocytes which differed from one another in their overall size. The distributions of cell diameters from all of the subject's smears showed highly significant positive skewing, in contrast to the more symmetrical distributions from the control smears.Analysis of bimodality, using a computer, indicated the presence of two normally distributed subpopulations. The results generated are given in table IV.Cytophotometric measurements of cellular DNA content can be used to analyze tetraploid-diploid mosaicism, since tetraploid cells have twice as much DNA as diploid cells. The large cells in peripheral blood from the subject had 2.01 times the stain content of his normal appearing cells, and 1.91 times that of the control. In order to estimate the incidence of tetraploidy among the subject's leukocytes, measurements were made on randomly selected cells and gave the results shown in table V.In the infant reported here, tetraploid-diploid mosaicism was evident only in the hematopoietic and lymphatic cells. Fibroblast cultures from skin, muscle and lung tissue were diploid. Different cell types showed different proportions of tetraploid cells, but these proportions were maintained throughout life. No functional abnormality was found in these tissues.Speculation: The marked growth disorder and congenital malformations of the infant discussed in this report indicate that there must have been severe disturbances present in other tissues. Perhaps tetraploid cells also occurred in those other tissues during the early stages of embryogenesis, but these cells were relatively deficient in their ability to undergo embryogenic differentiation and were gradually eliminated. The remaining diploid cells may have then been unable to compensate for the defunct tetraploid cells, thus leading to defects of organ development and of subsequent growth.

Published
1967
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42. PRIMITIVE ERYTHROPOIESIS IN EARLY CHICK EMBRYOGENESIS

Author

Campbell, G. Le M., Weintraub, H., Mayall, B. H., and Holtzer, H.

Abstract

Primitive erythroblasts in the circulating blood of the chick embryo continue to divide while synthesizing hemoglobin (Hb). Hb measurements on successive generations of erythroblasts show that there is a progressive increase in the Hb content of both interphase and metaphase cells. Furthermore, for any given embryo the Hb content of metaphase cells is always significantly greater than that of interphase cells. The distribution of Hb values for metaphase cells suggests that there are six Hb classes corresponding to the number of cell cycles in the proliferative phase. The location of erythroblasts in the cell cycle was determined by combining Feulgen cytophotometry with thymidine radioautography on the same cells. Measurements of the Hb content for erythroblasts in different compartments of the cell cycle (G1, S, G2, and M) show a progressive increase through the cycle. Thus, the amount of Hb per cell is a function of the number of cell divisions since the initiation of Hb synthesis and, to a lesser degree, the stage of the cell cycle. Earlier generations of erythroblasts synthesize Hb at a faster rate than the terminal generation. Several models have been proposed to explain these findings.

Published
1971
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43. Chromosome heteromorphism quantified by high-resolution bivariate flow karyotyping

Author

Trask, B, van den Engh, G, Mayall, B, and Gray, J W

Subjects
Indoles, Polymorphism, Genetic, Nucleic Acid Hybridization, Chromomycin A3, DNA, Flow Cytometry, Heterochromatin, Karyotyping, Bisbenzimidazole, Chromosomes, Human, Humans, Research Article, Fluorescent Dyes, Repetitive Sequences, Nucleic Acid
Abstract

Maternal and paternal homologues of many chromosome types can be differentiated on the basis of their peak position in Hoechst 33258 versus chromomycin A3 bivariate flow karyotypes. We demonstrate here the magnitude of DNA content differences among normal chromosomes of the same type. Significant peak-position differences between homologues were observed for an average of four chromosome types in each of the karyotypes of 98 different individuals. The frequency of individuals with differences in homologue peak positions varied among chromosome types: e.g., chromosome 15, 61%; chromosome 3, 4%. Flow karyotypes of 33 unrelated individuals were compared to determine the range of peak position among normal chromosomes. Chromosomes Y, 21, 22, 15, 16, 13, 14, and 19 were most heteromorphic, and chromosomes 2-8 and X were least heteromorphic. The largest chromosome 21 was 45% larger than the smallest 21 chromosome observed. The base composition of the variable regions differed among chromosome types. DNA contents of chromosome variants determined from flow karyotypes were closely correlated to measurements of DNA content made of gallocyanin chrome alum-stained metaphase chromosomes on slides. Fluorescence in situ hybridization with chromosome-specific repetitive sequences indicated that variability in their copy number is partly responsible for peak-position variability in some chromosomes. Heteromorphic chromosomes are identified for which parental flow karyotype information will be essential if de novo rearrangements resulting in small DNA content changes are to be detected with flow karyotyping.

Published
1989

47. Active surveillance for candidemia, Australia

Author

Chen, S., Slavin, M., Nguyen, Q., Marriott, D., Playford, E. G., Ellis, D., Tania Sorrell, Mcbride, J., Coulter, C., Mccormack, J., Walmsley, K., Looke, D., Johnson, B., Nimmo, G., Drummond, D., Forgan-Smith, R., Preston, E., Allworth, A., Faoagali, J., Gerns, N., Botes, J., Cherian, S., Robson, J., Vohra, R., Norton, R., O Kane, G., Robb, D., Gottlieb, T., Chambers, I., Dewit, D., Carroll, M., Dobson, P., Ferguson, J., Graves, S., Tierney, L., Jozwiak, F., Munro, R., Tomasotos, V., Pickles, R., Holland, J., Groenwald, F., Hale, K., Watson, M., Vaz, R., Hardiman, R., Baleriola, C., Ryan, S., Pritchard, R., Weeks, K., Benn, R., Adams, N., Lawrence, R., Taylor, P., Lindstrom, S., Harkness, J., Palasanthrian, P., Grant, R., Mcpetrie, R., Johnson, R., Halliday, C., Maszewska, K., Lee, O. C., Meyer, W., Dennis, N., Newton, P., Franklin, C., Morrisey, O., Spelman, D., Wesselingh, S., Speed, B., Hellsten, J., Mayall, B., Russell, J., Broughton, S., Woolley, I., Coloe, S., Sherman, A., Korman, T., Huysmans, M., Gordon, D., Rowlands, K., Shaw, D., Ferguson, W., Ritchie, B., Handke, R., Beaman, M., Chiam, A., Mccarthy, J., Heath, C., Altmann, S., Arthur, I., Speers, D., Cox, E., Cooley, L., Mcgregor, A., Currie, B., Lum, G., and Fisher, D.

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