Latex assay for serotyping of group B Streptococcus isolates

We developed a group B streptococcus (GBS) latex serotyping kit that reduces the numbers of GBS nontypeable isolates by nearly 50%. A total of 232 isolates were tested, and 203 isolates were serotyped by the GBS latex test, while the capillary precipitation test serotyped 184 isolates.

Situation analysis and epidemiology of infectious disease transmission: a South-East Asian regional perspective

This paper analyses the situation in countries comprising the WHO South-East Asia Region with respect to water supply and sanitation services, hygiene and the epidemiology of related infectious diseases. Recently, published data from the WHO/UNICEF Global Water Supply and Sanitation Assessment 2000 report was reviewed to depict the situation with respect to consumers' access to improved water supply and sanitation services. It was shown that access to improved drinking water supplies is among the lowest in the world, and that sanitation coverage in this region is below all others. The paper also reviews selected surveys of hygiene behaviours in several countries of the region. Associations are suggested between access to services, hygienic practices and specific infectious diseases. The need is acknowledged to improve the evidence base on linkages between infectious diseases and water, sanitation and hygiene, and specific recommendations are made in this regard. There is a need now and for the foreseeable future to promote low-cost household-level interventions, including behaviour change strategies, that mitigate the health consequences of the current situation with respect to water supply, sanitation and hygiene. The role of health authorities in meeting this challenge, and as advocates for accelerating development of the water and sanitation sector, is highlighted.

Providing clean water, keeping water clean: an integrated approach

Millions of people, most of whom are children in developing countries, die of basic hygiene-related diseases every year. Interventions in hygiene, sanitation and water supply have been shown to control disease burden. Universal access to improved water sources and basic sanitation remains elusive but is an important long-term goal. Studies have shown that improving the microbiological quality of household water by on-site or point-of-use treatment and safe storage in improved vessels reduces diarrhoeal and other waterborne diseases in communities and households of developing and developed countries. The extent to which improving drinking water quality at the household level reduces diarrhoeal disease probably depends on a variety of technology-related and site-specific environmental and demographic factors that require further investigation, characterisation and analyses.

Characterisation of the expression of a novel constitutive maize promoter in transgenic wheat and maize

A novel constitutive promoter from the maize histone H2Bgene was recently identified. In this study, we characterised H2B promoter activity in both wheat and maize tissues using the gusA reporter gene and two synthetic versions of the pat (phosphinothricin acetyl transferase) selectable marker gene, namely mopat and popat. Analyses of transgenic plants showed that the H2B promoter is able to drive the expression of gusA to strong, constitutive levels in wheat and maize tissues. Using an H2B:mopat construct and phosphinothricin selection, we recovered transgenic wheat plants at efficiencies ranging from 0.3% to 7.4% (mean 1.6%), and the efficiency of selection ranged from 40% to 100% (mean 77.7%). In another application, H2B was combined with the maize Ubi-1 or the maize Adh-1 intron to drive the expression of mopat and popat. Transformation efficiencies with the Ubi-1 intron were between 1.4- to 16-fold greater than with the Adh-1 intron. However, the use of either of the introns was necessary for the recovery of transgenic plants. Mopat gave higher transformation efficiencies and induced higher levels of PAT protein in maize tissues than popat.

Immunofluorescent patterns produced by antineutrophil cytoplasmic antibodies (ANCA) vary depending on neutrophil substrate and conjugate

BACKGROUND

The "International consensus statement on testing and reporting antineutrophil cytoplasmic antibodies (ANCA)" advocates screening by indirect immunofluorescence (IIF), but external quality assessment programmes often demonstrate different IIF patterns for a single serum.

AIM

To determine whether the variation in IIF patterns can be attributed solely to errors in interpretation.

METHODS

This study compared the IIF patterns produced by four sera (two with cytoplasmic or C-ANCA; one with perinuclear or P-ANCA with myeloperoxidase (MPO) specificity; and one P-ANCA without MPO specificity) that were tested in 11 different laboratories. The sera were examined according to individual laboratory protocols at dilutions of 1/10 to 1/40 using P1 (n = 4), P2 (n = 2), P3 (n = 2), or in house (n=3) neutrophil preparations and conjugates from manufacturers C1 (n = 3), C2 (n = 1), C3 (n = 2), C4 (n = 1), C5 (n = 2), and C6 (n = 2). The IIF patterns were noted in each laboratory, the testing repeated, and the fluorescent patterns photographed and subsequently discussed at a meeting of the Australian ANCA study group.

RESULTS

All IIF patterns described in individual laboratories were confirmed on retesting and by the ANCA study group. Neutrophil substrates produced commercially or in house varied in their ability to demonstrate cytoplasmic granularity and interlobular accentuation, which distinguish between "C-ANCA" and "C-ANCA (atypical)". All commercial and in house neutrophil substrates demonstrated neutrophil nuclear extension of P-ANCA fluorescence, which correlates with MPO specificity. However, eight assays (eight of 43) from eight laboratories resulted in IIF patterns different from those usually seen. One of these produced a C-ANCA (atypical) rather than a C-ANCA pattern. The other seven resulted in at least some cytoplasmic fluorescence when the consensus pattern was P-ANCA with (n = 4) or without (n = 3) MPO specificity. These assays used three different commercial and one in house neutrophil substrate, and six different conjugates, with anti-IgG, anti-(Fab)'(2), anti-Ig (heavy and light chain), and anti-G, A, and M activity. Four of the seven assays tested on commercial substrates had used the manufacturer's conjugates.

CONCLUSIONS

This study indicates that the variation in IIF patterns seen with ANCA positive sera tested in different laboratories does not necessarily result from errors in the interpretation of patterns and cannot be attributed solely to the use of a particular neutrophil substrate or conjugate, or to the use of substrate from one manufacturer and conjugate from another.

Wheat starch, gliadin, and the gluten-free diet

Individuals with celiac disease generally are advised to follow a lifelong gluten-free diet and avoid consumption of the prolamins gliadin (wheat), secalin (rye), and hordein (barley). Although the designation of the diet as glutenfree may imply that the diet contains zero gluten, this is not necessarily true. In some countries (eg, United States, Canada), the gluten-free diet is completely devoid of gluten and is based on foods such as rice and corn that are naturally gluten free. In others (eg, Scandinavia, United Kingdom), the gluten-free diet may include foods such as wheat starch that have been rendered gluten free but nonetheless contain small amounts of toxic prolamins. The discrepancy in the use of foods rendered gluten free exists because the amount of toxic prolamins that individuals with celiac disease may consume without damaging the mucosa of the small intestine is unknown. Minimal research has been conducted on the toxicity of foods rendered gluten free, and there are no definitive data about whether the small amount of prolamin found in these products is safe to consume. Nonetheless, the Codex Alimentarius Standard for gluten-free foods allows a certain amount of prolamin in foods designated gluten free, and these products have been used in many countries for several decades. Well-designed, scientifically sound studies are needed to help determine the amount of toxic prolamins, if any, that may be safely consumed by individuals with celiac disease. Until this research is conducted, dietitians in the United States should continue to advise their patients against the use of wheat starch and other foods rendered gluten free.

Phase I/II trial evaluating combined radiotherapy and in situ gene therapy with or without hormonal therapy in the treatment of prostate cancer--a preliminary report

PURPOSE

To report the preliminary results of a Phase I/II study combining radiotherapy and in situ gene therapy (adenovirus/herpes simplex virus thymidine kinase gene/valacyclovir) with or without hormonal therapy in the treatment of prostate cancer.

METHODS AND MATERIALS

Arm A: low-risk patients (T1-T2a, Gleason score <7, pretreatment PSA <10) were treated with combined radio-gene therapy. A mean dose of 76 Gy was delivered to the prostate with intensity-modulated radiotherapy. Arm B: high-risk patients (T2b-T3, Gleason score >or=7, pretreatment PSA >or=10) were treated with combined radio-gene therapy and hormonal therapy. Hormonal therapy was comprised of a 4-month leuprolide injection and 2-week use of flutamide. Arm C: Stage D1 (positive pelvic lymph node) patients received the same regimen as Arm B, with the additional 45 Gy to the pelvic lymphatics. Treatment-related toxicity was assessed using Cancer Therapy Evaluation Program common toxicity score and Radiation Therapy Oncology Group (RTOG) toxicity score.

RESULTS

Thirty patients (13 in Arm A, 14 in Arm B, and 3 in Arm C) completed the trial. Median follow-up was 5.5 months. Eleven patients (37%) developed flu-like symptoms (Cancer Therapy Evaluation Program Grade 1) of fatigue and chills/rigors after gene therapy injection but recovered within 24 h. Four patients (13%) and 2 patients (7%) developed Grade 1 and 2 fever, respectively. There was no patient with weight loss. One patient in Arm B developed Grade 3 elevation in liver enzyme, whereas 11 and 2 patients developed Grade 1 and 2 abnormal liver function tests. There was no Grade 2 or above hematologic toxicity. Three patients had transient rise in creatinine. There was no RTOG Grade 3 or above lower gastrointestinal toxicity. Toxicity levels were as follows: 4 patients (13%), Grade 2; 6 patients (20%), Grade 1; and 20 patients (67%), no toxicity. There was 1 patient with RTOG Grade 3 genitourinary toxicity, 12 patients (40%) with Grade 2, 8 patients (27%) with Grade 1, and 9 patients (30%) with no toxicity. No patient dropped out from the trial or had to withhold treatment because of severe toxicity.

CONCLUSIONS

This is the first trial of its kind in the field of prostate cancer that aims to expand the therapeutic index of radiotherapy by combining in situ gene therapy. Initial experience has demonstrated the safety of this approach. There is no added toxicity to each therapy used alone. Long-term follow-up and larger cohort studies are warranted to evaluate long-term toxicity and efficacy.

Legal and ethical considerations of forensic anthropological research

In the UK, Forensic Anthropology is maturing rapidly, consequently demanding discussion of previously overlooked yet fundamental principles of this discipline. UK law and ethics are interpreted from a forensic anthropological standpoint. First, the influence of UK law and ethics on the stages of forensic anthropological research (the collection, analysis and storage of human remains) are discussed. Existing ethical codes of conduct are investigated for their relevance to researching forensic anthropologists. It is concluded that: when appropriately interpreted, UK law and ethics are extremely influential on forensic anthropological research; debate within this area is required; and that an understanding of the law and ethical thought is vital for the successful growth of forensic anthropology in the UK.

Kinetic form discrimination in Prader-Willi syndrome

Discrimination of the shape of motion-produced forms generated by random elements (i.e. second-order stimuli varying in element density and temporal correlation) was tested in four groups: (1) subjects with Prader-Willi syndrome (PWS), chromosome 15q deletion subtype; (2) subjects with PWS, uniparental maternal disomy (UPD) subtype; (3) equivalent non-PWS controls; and (4) normal controls. The performance of the normal controls exceeded that of all other groups (78% correct, P < 0.009). The PWS deletion (66%) and the equivalent control groups (59%) did not differ (P < 0.95). The UPD group performed significantly less well (38%, P < 0.04) than all the other groups. The performance of the PWS deletion and equivalent control groups is consistent with other data indicating that these populations encounter difficulty meeting the processing demands posed by second-order stimuli. The inferior performance of the UPD group may be attributed to receiving two active alleles of a maternally expressed gene influencing neural development. One candidate is the ubiquitin protein ligase gene (UBE3A), which is maternally expressed only and localized to the 15q region. Other possibilities include the requirement of a paternally expressed gene, residual mosaic trisomy 15 in the brain tissue or complex interactions including specific ratios of differentially spliced gene products.

Efficacy of low tidal volume ventilation in patients with different clinical risk factors for acute lung injury and the acute respiratory distress syndrome

In patients with acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), a recent ARDS Network randomized controlled trial demonstrated that a low tidal volume (VT) mechanical ventilation strategy (6 ml/kg) reduced mortality by 22% compared with traditional mechanical ventilation (12 ml/kg). In this study, we examined the relative efficacy of low VT mechanical ventilation among 902 patients with different clinical risk factors for ALI/ARDS who participated in ARDS Network randomized controlled trials. The clinical risk factor for ALI/ARDS was associated with substantial variation in mortality. The risk of death (before discharge home with unassisted breathing) was highest in patients with sepsis (43%); intermediate in subjects with pneumonia (36%), aspiration (37%), and other risk factors (35%); and lowest in those with trauma (11%) (p < 0.0001). Despite these differences in mortality, there was no evidence that the efficacy of the low VT strategy varied by clinical risk factor (p = 0.76, for interaction between ventilator group and risk factor). There was also no evidence of differential efficacy of low VT ventilation in the other study outcomes: proportion of patients achieving unassisted breathing (p = 0.59), ventilator-free days (p = 0.58), or development of nonpulmonary organ failure (p = 0.44). Controlling for demographic and clinical covariates did not appreciably affect these results. After reclassifying the clinical risk factors as pulmonary versus nonpulmonary predisposing conditions and infection-related versus non-infection-related conditions, there was still no evidence that the efficacy of low VT ventilation differed among clinical risk factor subgroups. In conclusion, we found no evidence that the efficacy of the low VT ventilation strategy differed among clinical risk factor subgroups for ALI/ARDS.

Self-injurious behavior: gene-brain-behavior relationships

This paper summarizes a conference held at the National Institute of Child Health and Human Development on December 6-7, 1999, on self-injurious behavior [SIB] in developmental disabilities. Twenty-six of the top researchers in the U.S. from this field representing 13 different disciplines discussed environmental mechanisms, epidemiology, behavioral and pharmacological intervention strategies, neurochemical substrates, genetic syndromes in which SIB is a prominent behavioral phenotype, neurobiological and neurodevelopmental factors affecting SIB in humans as well as a variety of animal models of SIB. Findings over the last decade, especially new discoveries since 1995, were emphasized. SIB is a rapidly growing area of scientific interest to both basic and applied researchers. In many respects it is a model for the study of gene-brain-behavior relationships in developmental disabilities.

Sensitive method for nontransferrin-bound iron quantification by graphite furnace atomic absorption spectrometry

OBJECTIVE

To establish a sensitive method for measuring nontransferrin-bound iron (NTBI) in serum samples using graphite furnace atomic absorption spectrometry (GFAAS).

DESIGN AND METHODS

Nontransferrin-bound iron (NTBI) was chelated using nitrilotriacetic acid (NTA) and then ultrafiltered according to the method employed by Singh et al. [1]. Serum ultrafiltrates were diluted eightfold with distilled water. NTBI from the Fe-NTA complex present in the serum ultrafiltrate was measured using GFAAS.

RESULTS

Nontransferrin-bound iron (NTBI) and other parameters were measured in seven patients diagnosed with hereditary hemochromatosis by liver biopsy. Total serum iron, NTBI and transferrin saturation values (ranging from 87% to 90%) were elevated for three of the seven hemochromatosis patients tested before therapeutic phlebotomy. Six of the seven hemochromatosis patients had undergone phlebotomy and revealed normal total serum iron, NTBI and transferrin saturation values. Nine test subjects (not diagnosed with hemochromatosis) with abnormally high total serum iron and/or ferritin concentrations exhibited normal NTBI values (< or =0.14 micromol/L to 0.29 micromol/L). The detection limit was 0.1 micromol/L for a 25 microL injection volume.

CONCLUSIONS

The GFAAS method presented here provides a sensitive assay to quantitate NTBI in serum samples. The method developed is 4 to 5 times more sensitive than the only other GFAAS method [2] and more than an order of magnitude more sensitive than other colorimetric methods [1,3]. Improvement in sensitivity over the other GFAAS method [2] may be accounted for by differences in sample preparation between this method and that of Nielsen et al. [2]. Serum ultrafiltrates in this study were diluted eightfold with distilled water and mixed with a magnesium nitrate matrix modifier before GFAAS analysis. NTBI results obtained from this study indicate that the plasma iron pool in hemochromatosis patients awaiting phlebotomy increases to a level at which transferrin's ability to bind iron becomes exhausted and elevated NTBI levels appear in the serum. NTBI can mediate the production of reactive oxygen species and may cause organ damage associated with iron overload.