Relacorilant + Nab-Paclitaxel in Patients With Recurrent, Platinum-Resistant Ovarian Cancer: A Three-Arm, Randomized, Controlled, Open-Label Phase II Study

PURPOSE

Despite therapeutic advances, outcomes for patients with platinum-resistant/refractory ovarian cancer remain poor. Selective glucocorticoid receptor modulation with relacorilant may restore chemosensitivity and enhance chemotherapy efficacy.

METHODS

This three-arm, randomized, controlled, open-label phase II study (ClinicalTrials.gov identifier: NCT03776812) enrolled women with recurrent, platinum-resistant/refractory, high-grade serous or endometrioid epithelial ovarian, primary peritoneal, or fallopian tube cancer, or ovarian carcinosarcoma treated with ≤4 prior chemotherapeutic regimens. Patients were randomly assigned 1:1:1 to (1) nab-paclitaxel (80 mg/m2) + intermittent relacorilant (150 mg the day before, of, and after nab-paclitaxel); (2) nab-paclitaxel (80 mg/m2) + continuous relacorilant (100 mg once daily); or (3) nab-paclitaxel monotherapy (100 mg/m2). Nab-paclitaxel was administered on days 1, 8, and 15 of each 28-day cycle. The primary end point was progression-free survival (PFS) by investigator assessment; objective response rate (ORR), duration of response (DOR), overall survival (OS), and safety were secondary end points.

RESULTS

A total of 178 women were randomly assigned. Intermittent relacorilant + nab-paclitaxel improved PFS (hazard ratio [HR], 0.66; log-rank test P = .038; median follow-up, 11.1 months) and DOR (HR, 0.36; P = .006) versus nab-paclitaxel monotherapy, while ORR was similar across arms. At the preplanned OS analysis (median follow-up, 22.5 months), the OS HR was 0.67 (P = .066) for the intermittent arm versus nab-paclitaxel monotherapy. Continuous relacorilant + nab-paclitaxel showed numerically improved median PFS but did not result in significant improvement over nab-paclitaxel monotherapy. Adverse events were comparable across study arms, with neutropenia, anemia, peripheral neuropathy, and fatigue/asthenia being the most common grade ≥3 adverse events.

CONCLUSION

Intermittent relacorilant + nab-paclitaxel improved PFS, DOR, and OS compared with nab-paclitaxel monotherapy. On the basis of protocol-prespecified Hochberg step-up multiplicity adjustment, the primary end point did not reach statistical significance (P < .025). A phase III evaluation of this regimen is underway (ClinicalTrials.gov identifier: NCT05257408).

Overall survival data from a 3-arm, randomized, open-label, phase 2 study of relacorilant, a selective glucocorticoid receptor modulator, combined with nab-paclitaxel in patients with recurrent platinum-resistant ovarian cancer

LBA5503

Background: Cortisol contributes to chemotherapy resistance by suppressing apoptotic pathways that cytotoxic agents utilize. Preclinical and clinical data indicate that glucocorticoid receptor (GR) modulation with relacorilant (RELA) reverses the anti-apoptotic effects of cortisol and restores the efficacy of cytotoxic agents. We report overall survival (OS) results from a randomized, controlled phase 2 study of RELA + nab-paclitaxel (NP) compared to NP only in patients with ovarian cancer (NCT03776812). The primary analysis showed improved progression-free survival (PFS) and a favorable safety profile with intermittent RELA + NP vs NP only, despite overrepresentation of primary platinum-refractory patients in the intermittent RELA + NP (n = 7) vs the NP-only arm (n = 1). Methods: A phase 2, open-label, randomized, 3-arm study of 2 RELA dosing schedules + NP compared with NP only was performed. 178 women with recurrent, platinum-resistant/refractory, high-grade serous or endometrioid epithelial ovarian, primary peritoneal, or fallopian tube cancer or ovarian carcinosarcoma with ≤4 prior chemotherapeutic regimens were enrolled. Patients were randomized 1:1:1 to: a) NP (80 mg/m2) + intermittent RELA (150 mg QD the day before, of, and after NP) (n = 60); b) NP (80 mg/m2) + continuous RELA (100 mg QD) (n = 58); or c) NP only (100 mg/m2) (n = 60). NP was administered on days 1, 8, and 15 of each 28-day cycle. The primary endpoint was PFS; OS was a secondary endpoint. OS data for the intermittent and continuous arms were compared to NP only using a 2-sided log-rank test, stratified by presence of ascites and relapse within 6 months on previous taxane, at a 0.05 level of significance without multiplicity adjustment. Results: At the pre-defined OS analysis (128 OS events), hazard ratios (HRs) were 0.67 (95% CI [0.43, 1.03], P= 0.066) and 0.85 (95% CI [0.56, 1.29], P= 0.447) for intermittent and continuous RELA + NP vs NP only. Median OS was 13.9 (95% CI [11.1, 18.4]), 11.3 (95% CI [7.5, 16.4]), and 12.2 (95% CI [7.7, 15.3]) months in the intermittent RELA + NP, continuous RELA + NP, and NP-only arms. In the subgroup of patients without primary platinum-refractory disease, a statistically significant improvement in OS was observed with HR 0.63 (95% CI [0.39, 0.99], P= 0.045) and median OS of 13.9 (95% CI [11.1, 18.4]) vs 12.2 (95% CI [7.7, 15.3]) months for intermittent RELA + NP vs NP only. Conclusions: In addition to the improved PFS and DOR observed at the primary analysis, the OS analysis confirmed the survival benefit of intermittent RELA + NP compared to NP only, particularly in patients who were not primary platinum refractory. A phase 3 trial evaluating intermittent RELA + NP vs investigator’s choice of chemotherapy in patients without primary platinum-refractory disease is ongoing (NCT05257408). Clinical trial information: NCT03776812.

ROSELLA: A phase 3 study of relacorilant in combination with nab-paclitaxel versus investigator’s choice in advanced, platinum-resistant, high-grade epithelial ovarian, primary peritoneal, or fallopian-tube cancer

TPS5620

Background: Chemotherapy resistance is a major concern in the treatment of advanced platinum-resistant and platinum-refractory ovarian cancer. One mechanism of resistance is driven by cortisol, which can suppress the apoptotic pathways that chemotherapy agents rely upon, eg, suppression of BCL2 and FOXO3a pathways. Preclinical and clinical data indicate that glucocorticoid receptor (GR) antagonism may reverse the anti-apoptotic effects of cortisol, thereby restoring the efficacy of cytotoxic agents. Relacorilant is a selective GR modulator that has shown promise in overcoming resistance when combined with taxanes (particularly nab-paclitaxel) in preclinical models (Greenstein & Hunt 2021) and early-phase clinical studies (Munster et al. 2019) in various solid tumors. A randomized, controlled phase 2 study of relacorilant + nab-paclitaxel found clinically meaningful improvements in progression-free survival (PFS) and duration of response (DOR) without increased side effect burden in patients with recurrent, platinum-refractory and platinum-resistant ovarian cancer (Colombo et al. 2021). The aim of this phase 3 study is to confirm these phase 2 findings in a larger patient population. Methods: ROSELLA (EudraCT 2022-000662-18, NCT pending) is a phase 3, randomized, 2-arm, open-label, multicenter study of relacorilant + nab-paclitaxel compared to investigator’s choice of chemotherapy agents in patients with confirmed high-grade serous epithelial ovarian, primary peritoneal, or fallopian tube cancer. The trial is being conducted at multiple sites in North America and Europe and has a planned enrollment of 360 patients. Patients are randomized 1:1 to either relacorilant (150 mg the day before, day of, and day after nab-paclitaxel infusion) + nab-paclitaxel (80 mg/m2 on days 1, 8, and 15 of each 28-day cycle) or investigator’s choice of chemotherapy (liposomal doxorubicin, paclitaxel, topotecan, or nab-paclitaxel). Randomization is stratified by prior lines of therapy (1 vs > 1), region of world (North America vs Europe), and prior bevacizumab (yes/no). Adult female patients with platinum-resistant disease (progression within 6 months of completion of platinum-containing therapy), excluding patients with primary platinum refractory disease, who have received 1–3 lines of prior systemic anticancer therapy and at least 1 prior line of platinum therapy are being enrolled. Life expectancy ≥3 months, adequate organ function, and ECOG performance status of 0 or 1 are required. The primary study endpoint is PFS by blinded independent central review. Key secondary endpoints include overall survival, PFS by investigator, overall response rate, best overall response, DOR, clinical benefit rate, safety, quality of life, CA-125, pharmacodynamics, and pharmacokinetics. Clinical trial information: 2022-000662-18.

A critical review on life cycle assessment and plant-wide models towards emission control strategies for greenhouse gas from wastewater treatment plants

For decades, there has been a strong interest in mitigating greenhouse gas (GHG) emissions from wastewater treatment plants (WWTPs). Numerous models were developed to measure the emissions and propose the quantification. Existing studies looked at the relationship between GHG emissions and operational cost (OCI), which is one of the most important indicators for decision-makers. Other parameters that can influence the control strategies include the effluent quality (EQI) and total environmental impacts. Plant-wide models are reliable methods to examine the OCI, EQI and GHG emissions while Life cycle assessment (LCA) works to assess the potential environmental impacts. A combined LCA and plant-wide model proved to be a valuable tool evaluating and comparing strategies for the best performance of WWTPs. For this study involving a WWTP, the benchmark model is used while LCA is the decision tool to find the most suitable treatment strategy. LCA adds extra criteria that complement the existing criteria provided by such models. Complementing the cost/performance criteria is proposed for plant-wide models, including environmental evaluation, based on LCA, which provides an overall better assessment of WWTPs. It can capture both the dynamic effects and potential environmental impacts. This study provides an overview of the integration between plant-wide models and LCA.

0425 Severity of Insomnia Symptoms Differ by Cognitive Status in Adults with Down Syndrome

Introduction

Sleep is disturbed in Down syndrome (DS), with sleep apnea and insomnia prevalent throughout life. Sleep disturbance increases dementia risk and is more prevalent in dementia in non-DS populations. However, relationships between sleep and clinical status in DS remains unclear. We examined informant-reported sleep in adults with DS, with or without a consensus diagnosis of dementia, and related the severity of sleep disturbances to measures of adaptive behavior.

Methods

Insomnia (selected from Children’s Sleep Habits Questionnaire), daytime sleepiness (modified ESS), sleep apnea risk (modified STOP-BANG), and adaptive behavior (Vineland Adaptive Behavior Scales; VABS-3) questionnaires were collected from informants for 47 DS adults (52.1±6.6 years) enrolled in a Alzheimer’s disease biomarker study. Participants’ clinical statuses were categorized as cognitively unaffected (clinically significant impairment absent; n=38, 51.0±6.2 years), or as having definite dementia (clinically significant decline present; n=9, 56.6±6.4 years) using a standard consensus diagnosis procedure. Age was compared between groups using an independent samples t-test. ANCOVA was used to compare insomnia, daytime sleepiness, sleep apnea risk, and adaptive behavior measures across groups, while controlling for age. Partial correlation analyses examined associations between sleep measures and VABS-3 measures while controlling for clinical status.

Results

Participants categorized as definite dementia were older (t=-2.381, p=0.022). ANCOVA determined that insomnia symptoms, but not daytime sleepiness or apnea risk, were more severe in definite dementia participants (F=5.567, p=0.023), even when controlling for age. VABS-3 subscale scores differed by clinical status (all save play and leisure scores p&lt;0.017). Partial correlation analyses adjusting for clinical status indicated that insomnia symptom severity worsened with lower adaptive functioning (e.g., daily living skills—coping r=-0.41, p=0.007; socialization r=-0.33, p=0.024) regardless of clinical status.

Conclusion

These findings indicate that insomnia may be related to functional impairment and dementia in DS adults, and raises the possibility that insomnia treatments may influence dementia course and clinical symptomatology in DS.

Support

NIH U01AG051412

Microalgae biomass from swine wastewater and its conversion to bioenergy

Ever-increasing swine wastewater (SW) has become a serious environmental concern. High levels of nutrients and toxic contaminants in SW significantly impact on the ecosystem and public health. On the other hand, swine wastewater is considered as valuable water and nutrient source for microalgae cultivation. The potential for converting the nutrients from SW into valuable biomass and then generating bioenergy from it has drawn increasing attention. For this reason, this review comprehensively discussed the biomass production, SW treatment efficiencies, and bioenergy generation potentials through cultivating microalgae in SW. Microalgae species grow well in SW with large amounts of biomass being produced, despite the impact of various parameters (e.g., nutrients and toxicants levels, cultivation conditions, and bacteria in SW). Pollutants in SW can effectively be removed by harvesting microalgae from SW, and the harvested microalgae biomass elicits high potential for conversion to valuable bioenergy.

Challenges in the application of microbial fuel cells to wastewater treatment and energy production: A mini review

Wastewater is now considered to be a vital reusable source of water reuse and saving energy. However, current wastewater has multiple limitations such as high energy costs, large quantities of residuals being generated and lacking in potential resources. Recently, great attention has been paid to microbial fuel cells (MFCs) due to their mild operating conditions where a variety of biodegradable substrates can serve as fuel. MFCs can be used in wastewater treatment facilities to break down organic matter, and they have also been analysed for application as a biosensor such as a sensor for biological oxygen which demands monitoring. MFCs represent an innovation technology solution that is simple and rapid. Despite the advantages of this technology, there are still practical barriers to consider including low electricity production, current instability, high internal resistance and costly materials used. Thus, many problems must be overcome and doing this requires a more detailed analysis of energy production, consumption, and application. Currently, real-world applications of MFCs are limited due to their low power density level of only several thousand mW/m². Efforts are being made to improve the performance and reduce the construction and operating costs of MFCs. This paper explores several aspects of MFCs such as anode, cathode and membrane, and in an effort to overcome the practical challenges of this system.

Problematic effects of antibiotics on anaerobic treatment of swine wastewater

Swine wastewaters with high levels of organic pollutants and antibiotics have become serious environmental concerns. Anaerobic technology is a feasible option for swine wastewater treatment due to its advantage in low costs and bioenergy production. However, antibiotics in swine wastewater have problematic effects on micro-organisms, and the stability and performance of anaerobic processes. Thus, this paper critically reviews impacts of antibiotics on pH, COD removal efficiencies, biogas and methane productions as well as the accumulation of volatile fatty acids (VFAs) in the anaerobic processes. Meanwhile, impacts on the structure of bacteria and methanogens in anaerobic processes are also discussed comprehensively. Furthermore, to better understand the effect of antibiotics on anaerobic processes, detailed information about antimicrobial mechanisms of antibiotics and microbial functions in anaerobic processes is also summarized. Future research on deeper knowledge of the effect of antibiotics on anaerobic processes are suggested to reduce their adverse environmental impacts.

Can algae-based technologies be an affordable green process for biofuel production and wastewater remediation?

Algae is a well-known organism that its characteristic is prominent for biofuel production and wastewater remediation. This critical review aims to present the applicability of algae with in-depth discussion regarding three key aspects: (i) characterization of algae for its applications; (ii) the technical approaches and their strengths and drawbacks; and (iii) future perspectives of algae-based technologies. The process optimization and combinations with other chemical and biological processes have generated efficiency, in which bio-oil yield is up to 41.1%. Through life cycle assessment, algae bio-energy achieves high energy return than fossil fuel. Thus, the algae-based technologies can reasonably be considered as green approaches. Although selling price of algae bio-oil is still high (about $2 L^-1) compared to fossil fuel's price of $1 L^-1, it is expected that the algae bio-oil's price will become acceptable in the next coming decades and potentially dominate 75% of the market.

Bioprocessing for elimination antibiotics and hormones from swine wastewater

Antibiotics and hormones in swine wastewater have become a critical concern worldwide due to the severe threats to human health and the eco-environment. Removal of most detectable antibiotics and hormones, such as sulfonamides (SAs), SMs, tetracyclines (TCs), macrolides, and estrogenic hormones from swine wastewater utilizing various biological processes were summarized and compared. In biological processes, biosorption and biodegradation are the two major removal mechanisms for antibiotics and hormones. The residuals in treated effluents and sludge of conventional activated sludge and anaerobic digestion processes can still pose risks to the surrounding environment, and the anaerobic processes' removal efficiencies were inferior to those of aerobic processes. In contrast, membrane bioreactors (MBRs), constructed wetlands (CWs) and modified processes performed better because of their higher biodegradation of toxicants. Process modification on activated sludge, anaerobic digestion and conventional MBRs could also enhance the performance (e.g. removing up to 98% SMs, 88.9% TCs, and 99.6% hormones from wastewater). The hybrid process combining MBRs with biological or physical technology also led to better removal efficiency. As such, modified conventional biological processes, advanced biological technologies and MBR hybrid systems are considered as a promising technology for removing toxicants from swine wastewater.

Paired Phase II Studies of Erlotinib/Bevacizumab for Advanced Bronchioloalveolar Carcinoma or Never Smokers With Advanced Non-Small-cell Lung Cancer: SWOG S0635 and S0636 Trials

BACKGROUND

Before mutation testing of the epidermal growth factor receptor (EGFR) gene was recognized as highly associated with the activity of EGFR tyrosine kinase inhibitors (TKIs), clinically defined patient populations with bronchioloalveolar carcinoma (BAC) and never smokers were identified as likely to benefit from EGFR TKIs. From preclinical and clinical data suggesting potentially improved efficacy with a combination of an EGFR TKI and the antiangiogenic agent bevacizumab, the Southwestern Oncology Group (SWOG) initiated paired phase II trials to evaluate the combination of erlotinib/bevacizumab in patients with advanced BAC (SWOG S0635) or never smokers with advanced lung adenocarcinoma (SWOG S0636).

MATERIALS AND METHODS

Eligible patients with BAC or adenocarcinoma with BAC features (SWOG S0635) or never smokers with advanced lung adenocarcinoma (SWOG S0636) received erlotinib 150 mg/day with bevacizumab 15 mg/kg until progression or prohibitive toxicity. Never smokers with BAC were preferentially enrolled to SWOG S0636. The primary endpoint for both trials was overall survival.

RESULTS

A total of 84 patients were enrolled in the SWOG S0635 trial and 85 in the SWOG S0636 trial. The objective response rate was 22% (3% complete response) in the SWOG S0635 trial and 50% (38% confirmed; 3% complete response) in the SWOG S0636 trial. The median progression-free survival was 5 and 7.4 months in the S0635 and S0636 trials, respectively. The median overall survival was 21 and 29.8 months, respectively. Toxicity consisted mainly of rash and diarrhea in both trials.

CONCLUSION

Although the field has moved toward molecular, rather than clinical, selection of patients as optimal candidates for EGFR TKI therapy, these results support the hypothesis that a subset of patients in whom erlotinib is particularly active could receive an incremental benefit from the addition of bevacizumab.

Effects of C/N ratio on the performance of a hybrid sponge-assisted aerobic moving bed-anaerobic granular membrane bioreactor for municipal wastewater treatment

This study aimed to evaluate the impact of C/N ratio on the performance of a hybrid sponge-assisted aerobic moving bed-anaerobic granular membrane bioreactor (SAAMB-AnGMBR) in municipal wastewater treatment. The results showed that organic removal efficiencies were above 94% at all C/N conditions. Nutrient removal was over 91% at C/N ratio of 100/5 but was negatively affected when decreasing C/N ratio to 100/10. At lower C/N ratio (100/10), more noticeable membrane fouling was caused by aggravated cake formation and pore clogging, and accumulation of extracellular polymeric substances (EPS) in the mixed liquor and sludge cake as a result of deteriorated granular quality. Foulant analysis suggested significant difference existed in the foulant organic compositions under different C/N ratios, and humic substances were dominant when the fastest fouling rate was observed. The performance of the hybrid system was found to recover when gradually increasing C/N ratio from 100/10 to 100/5.

New onset idiosyncratic liver enzyme elevations with biological therapy in inflammatory bowel disease

BACKGROUND

Anti-tumour necrosis factor α (anti-TNF) agents have been implicated in drug-induced liver injury. There is minimal data on this occurrence in inflammatory bowel disease (IBD) patients.

AIM

To identify the characteristics of liver enzyme elevations following anti-TNF therapy initiation in IBD.

METHODS

A retrospective cohort of patients initiating anti-TNF therapy were analysed for new onset alanine transaminase (ALT) elevation (≥60 U/L). We collected data on natural history, outcomes and patient characteristics compared with controls with persistent normal liver enzymes. Likelihood of causal association was assessed using the RUCAM score.

RESULTS

From 1753 patients initiating an anti-TNF (1170 infliximab, 575 adalimumab, 8 certolizumab), 102 (6%) developed new onset ALT elevation. In 54 (53%), this could be linked to an alternate aetiology. Among those with idiopathic ALT elevations, the median time to ALT elevation from anti-TNF initiation was 18 weeks and median peak ALT was 96 U/L. Six underwent liver biopsy, all demonstrating hepatitis with autoimmune features. Compared to controls, cases were on a lower dose of infliximab (5.7 vs. 6.7 mg/kg, P = 0.02) but were otherwise similar in body mass index, sex and age. On follow-up, 34 continued the anti-TNF, 14 stopped therapy and 4 initiated steroids. Most (85%) normalised their LFTs after a median of 17 weeks including 28 (82%) of those who continued anti-TNF therapy. Ten patients were transitioned to a second anti-TNF without recurrence.

CONCLUSIONS

ALT elevations occurred in 6% of IBD patients initiating anti-TNF therapy. Most idiopathic elevations were mild, transient and resolved despite therapy continuation.

Photo-physics study of an hydroxy-quinoline derivative as inhibitor of Pim-1 kinase: ultraviolet-visible linear dichroism spectroscopy and quantum chemical calculations

The photophysical properties of the antiviral 7-nicotinoyl-styrylquinoline (MB96) were investigated by means of UV-Vis linear dichroism (LD) spectroscopy on molecular samples aligned in stretched polyvinylalcohol (PVA), supported by time dependent density functional theory (TD-DFT) calculations. Experimentally, the directions of the transitions moments with respect to the long axis of the molecule were deduced from the orientation K factors, determined by means of "trial-and-error" procedure. The absorption spectrum presents two parts. The main transition in the lowest energy part, observed around 365 nm and showing the highest K value 0.8, is longitudinally in-plane polarized. The highest energy part which is extended between 230 and 320 nm, large, diffuse, and of weak intensity, shows estimated K values between 0.2 and 0.5. This complex structure is transversally polarized with some contamination by the longitudinal character of the first strong band. The TD-DFT results agree fairly well with the LD measurements.

Long-term outcome of a third anti-TNF monoclonal antibody after the failure of two prior anti-TNFs in inflammatory bowel disease

BACKGROUND

A significant proportion of patients with IBD lose response to anti-TNF therapies. There is limited knowledge of the long-term outcomes of those who have failed two anti-TNF agents and commenced a third.

AIM

To examine the safety and efficacy of third anti-TNF treatment after failure of two prior anti-TNF agents in patients with inflammatory bowel disease.

METHODS

This was a retrospective study of all IBD patients [Crohn's disease (CD), ulcerative colitis (UC)] treated with a third anti-TNF agent after loss of response or intolerance to two prior anti-TNF agents at a single tertiary North American centre. Disease activity, drug therapy and Montreal phenotypes were noted at disease onset and commencement of the third anti-TNF agent. Kaplan-Meier estimates were used to calculate the probability of remaining on the third anti-TNF agent and to identify predictors of long-term clinical response.

RESULTS

A total of 63 patients (64% women, 57 CD and 6 UC) were included in the analysis. The mean disease duration at initiation of third anti-TNF was 12 years. Thirty-five (55.6%) patients discontinued the third anti-TNF after a mean of 13.2 months. Probability of remaining on the third anti-TNF was 0.69, 0.55, 0.37 and 0.25 at 6, 12, 24 and 36 months respectively. Prior primary nonresponders to the first anti-TNF agent [hazard ratio (HR) 6.4, 95% CI 2.5-16.1] and persistent disease activity at 3 months after commencement of a third anti-TNF (HR 3.2, 95% CI 1.3-7.8) predicted poorer response.

CONCLUSIONS

Over half of patients with inflammatory bowel disease, initiated on a third anti-TNF agent after failure of two prior anti-TNF drugs, are able to remain on the third anti-TNF at 1 year.

Synthesis of ethanol-soluble few-layer graphene nanosheets for flexible and transparent conducting composite films

We report a facile method of preparing few-layer graphene nanosheets (FLGs), which can be soluble in ethanol. Atomic force microscopy and high-resolution transmission electron microscopy studies reveal that FLGs have average thicknesses in the range of 2.6-2.8 nm, corresponding to 8-9 layers. A graphene/nafion composite film has a sheet resistance of 9.70 kΩ/sq at the transmittance of 74.5% (at 550 nm) while the nafion film on polyethylene terephthalate has a sheet resistance of 128 kΩ/sq at transmittance of 90.0%. For the cycling/bending test, almost no change in resistance was exhibited when the film was bent at an angle up to 140°, and no obvious deviation in resistance could be found after 100 bending cycles was applied. In addition, an FLGs-poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) composite layer was demonstrated as the effective hole transporting layer to improve the hole transporting ability in an organic photovoltaic device, with which the power conversion efficiency was enhanced from 3.10% to 3.70%. The results demonstrated the promising applications of FLGs on graphene-based electronics, such as transparent electrode and flexible conducting film.

Blood donor satisfaction and intention of future donation

BACKGROUND

New regulatory requirements for donor eligibility challenge blood centers to recruit and retain enough donors. This study evaluated correlations between overall satisfaction with the donation process and donor demographics and the effect of both on a donor's intent to return.

STUDY DESIGN AND METHODS

An anonymous, self-administered questionnaire was given to donors at multiple sites of one blood center over a 3-week period. First-time and repeat donors were asked questions on demographic characteristics, satisfaction with the current donation process, motivation for current and future donations, and intent to return.

RESULTS

More than 75 percent of donors rated the overall donation process at 9 or 10 on a scale of 10 (mean, 9.19; standard deviation, 1.09), with female, high school-educated, and first-time donors giving higher satisfaction ratings than male, college-educated, and repeat donors, respectively (all p < 0.001). Donor satisfaction was correlated with intent to return for another donation (p = 0.002). For the current donation, donors rated altruistic motivations most highly. Medical testing was the most highly rated incentive for future donations, followed by frequent donor programs and convenient donation times and locations; preferences varied by demographic subgroup.

CONCLUSIONS

Blood donor satisfaction varies among demographic and donation history subgroups and is positively correlated with the intent to return for future donation. Although the primary motivation among all donors was altruism, incentives to future donation may need to be tailored according to demographic subgroups.

A double-blind, placebo-controlled trial of sibutramine for clozapine-associated weight gain

This study sought to examine the effectiveness of sibutramine, a weight loss agent, on clozapine-associated weight gain.

METHOD

This was a 12-week double-blind, placebo controlled, randomized trial of sibutramine for weight loss in obese clozapine-treated schizophrenia or schizoaffective disorder subjects.

RESULTS

Ten patients were enrolled into the placebo group and 11 patients into the sibutramine group. There were no significant baseline differences between the two groups on age, gender, education, ethnicity, diagnosis, weight, body mass index (BMI), and blood pressure. At week 12, there were no significant differences in changes in weight, BMI, abdominal and waist circumferences, Hba1c, fasting glucose, or cholesterol levels.

CONCLUSION

Sibutramine treatment did not show significant weight loss compared with placebo in clozapine-treated patients with schizophrenia or schizoaffective disorder. Further research with a larger sample size and longer follow-up duration is warranted.

Homocysteine levels and glucose metabolism in non-obese, non-diabetic chronic schizophrenia

OBJECTIVE

We studied a sample of schizophrenia out-patients to test the hypotheses that serum homocysteine concentrations would correlate positively with measures of glucose metabolism.

METHOD

Subjects underwent a nutritional assessment and fasting plasma, serum insulin and homocysteine tests.

RESULTS

Males had a significantly higher homocysteine levels than females (7.69 +/- 1.42 microM vs. 6.63 +/- 1.40 microM; P = 0.02). Comparing subjects with normal fasting glucose (NFG) (glucose < 100 mg/dl) and impaired fasting glucose (IFG) (> or = 100 mg/dl) subjects with IFG (mean 8.2 +/- 1.5 microM) had significantly higher homocysteine levels than those with NFG (mean 7.2 +/- 1.4 microM, P = 0.03). IFG was also associated with greater mean values for a Homeostatic Model Assessment-Insulin Resistance (HOMA-IR) (P = 0.002) and diastolic blood pressure (P = 0.045).

CONCLUSION

The group with IFG had higher fasting serum homocysteine concentrations than those with NFG which supports a connection to an important cardiovascular risk factor.

An exploratory open-label trial of aripiprazole as an adjuvant to clozapine therapy in chronic schizophrenia

OBJECTIVE

We conducted this 6-week open-label trial to examine the effects of adjunctive aripiprazole in clozapine-treated subjects on weight, lipid and glucose metabolism, as well as positive and negative symptoms of schizophrenia.

METHOD

Ten clozapine-treated subjects received aripiprazole augmentation; eight completed the 6-week trial and two ended at week 4. Eighty percent were male, the mean age was 38.7 +/- 8.9 years and the mean clozapine dose was 455 +/- 83 mg daily.

RESULTS

There was a significant decrease in weight (P = 0.003), body mass index (P = 0.004), fasting total serum cholesterol (P = 0.002) and total triglycerides (P = 0.04) comparing baseline to study endpoint. There was no significant change in total Positive and Negative Syndrome Scale scores.

CONCLUSION

This combination may be useful for clozapine-associated medical morbidity and must be studied in placebo-controlled double-blind randomized trials to determine efficacy and safety.

Plasmablastic lymphoma presenting in a human immunodeficiency virus-negative patient: a case report

Plasmablastic lymphoma (PBL), an aggressive non-Hodgkin's lymphoma that carries a poor prognosis, previously has been identified almost exclusively in patients infected with the human immunodeficiency virus (HIV). We present a case of a 42-year-old HIV-negative patient presenting with an isolated nasal cavity mass, the typical presentation for PBL. The patient was given systemic chemotherapy, central nervous system prophylaxis, and consolidative locoregional radiotherapy and achieved a complete clinical response. This case suggests PBL should be considered in HIV-negative patients with characteristic findings.

Cytomegalovirus viremia during Campath-1H therapy for relapsed and refractory chronic lymphocytic leukemia and prolymphocytic leukemia

Campath-1H is effective therapy for patients with relapsed and refractory chronic lymphocytic leukemia (CLL) and prolymphocytic leukemia (PLL), but it is associated with profound lymphopenia and deficiencies in cell-mediated immunity. We report the incidence of cytomegalovirus (CMV) viremia in 34 patients treated with Campath-1H for relapsed or refractory CLL and PLL. All patients received infection prophylaxis during therapy and continuing for at least 2 months following Campath-1H. Five patients (15%) developed CMV viremia at a median of 28 days (range, 20-30 days) after the first dose of Campath-1H. The median CMV viral load was 860/mL (range, 420-2100/mL), as determined by quantitative plasma polymerase chain reaction (PCR). All 5 patients had a temperature > 38.5 degrees C, normal chest radiographs, normal liver function tests, and negative bacterial blood cultures with no clinical evidence of CMV disease at the time of presentation with CMV viremia. The median absolute neutrophil count (ANC) was 740/ microL (range, 340-1600/ microL), and the median absolute lymphocyte count (ALC) was 16/microL (range, 11-169/ microL) for the 5 patients at the time of CMV viremia. All 5 patients received ganciclovir therapy followed by prompt fever resolution and clearance of CMV viremia by plasma PCR. By univariate regression analysis, the following were not risk factors for CMV viremia: age, number of prior regimens, prior rituximab therapy, prior splenectomy, modified Rai stage at Campath-1H therapy (low/intermediate vs. high), ANC, and ALC; although, there was a trend towards significance for prior rituximab therapy (P = 0.07). Cytomegalovirus viremia may be a significant infectious complication during Campath-1H therapy and should be investigated further in future studies.

Mechanisms of cholinergic dysfunction in rabbits following recurrent aspiration of cow's milk

Recurrent aspiration of cow's milk has been shown to alter neural control of airways in young rabbits (Gelfand et al., 1997). The purpose of this study was to define the mechanisms responsible for in vitro cholinergic hyperresponsiveness in this model. Beginning at 1 week of age, rabbits received either 0.5 mL/kg whole cow's milk or sterile saline intranasally while under light anesthesia. This was repeated each weekday for 2 weeks. At 8 weeks of age, rabbits were sacrificed. Portions of lungs underwent lavage with sterile saline. Tracheal smooth muscle (TSM) segments were also removed. Segments were assessed for acetylcholine (ACh) release by high-performance liquid chromatography ( HPLC) with electrochemical detection or acetylcholinesterase (AChE) kinetic activity by spectrophotometry. Substance P (SP), a neuropeptide that can increase ACh release from nerves, was also assessed using an enzyme immunoassay to define the content in lavage and TSM segments. Immunohistochemistry for SP within airways was also assessed. We found that recurrent aspiration of milk led to statistically significant alterations in many parameters. Acetylcholine release was significantly greater in segments of airways from rabbits that had aspirated cow's milk (27.5 +/- 1.7 vs. 20.1 +/- 1.6 pmol/min/g tissue) than saline. At the same time, AChE activity was less in the group that aspirated milk (8.7 +/- 0.4 vs. 10.2 +/- 0.5 nmol/min/mg protein) compared to saline. The amount of SP within both lavage as well as tissue homogenates was greater in the group that had aspirated the foreign protein (159.1 +/- 28.9 vs. 41.9 +/- 5.2 pmol/mg protein in lavage; 158.7 +/- 31.9 vs. 80.5 +/- 7.8 pmol/mg protein in tissues) than saline controls. While total cholinergic nerve density as assessed by choline acetyltransferase was not significantly different between groups, SP-positive immunoreactive nerves were easily identified in the group that aspirated cow's milk. This study suggests that cholinergic hyperresponsiveness caused by repeated aspiration of milk is due to several abnormalities, including prejunctional (increase in ACh release) as well as junctional (decrease in AChE) mechanisms within the airways. In addition, an upregulation of SP within airways is part of this process.

Evidence of skewed X-chromosome inactivation in 47,XXY and 48,XXYY Klinefelter patients

Klinefelter (47,XXY) syndrome occurs in approximately 1:800 male births and accounts for about 10-20% of males attending infertility clinics. Recent studies have shown no obvious phenotypic differences between subjects in which the extra X-chromosome is of paternal or maternal origin; however, a minority of Klinefelter patients are adversely affected clinically and intellectually to an exceptional level, and the underlying basis of this phenotypic variation is not known. We hypothesize that skewed X-inactivation and possibly parental origin of the X-chromosomes is involved. In this study, we determined parental origin and inactivation status of the X-chromosomes in 17 cytogenetically confirmed 47,XXY cases, two 48,XXYY cases and one mosaic 46,XY/47,XXY case. Eight highly polymorphic markers specific to the X-chromosome and the polymorphic human androgen-receptor (HUMARA) methylation assay were used to determine the parental origin and X-inactivation status of the X-chromosomes, respectively. Overall, 17 cases were fully informative, enabling parental origin to be assigned. In 59% of cases, both X-chromosomes were of maternal origin (Xm); in the remaining 41%, one X was of maternal (Xm) and one was of paternal origin (Xp). In 5 of 16 (31%) cases informative at the HUMARA locus, skewed X-inactivation was observed as defined by greater than 80% preferential inactivation involving one of the two X-chromosomes. The two 48,XmXpYY cases both showed preferential paternal X-chromosome (Xp) inactivation. Three 47,XmXmY cases also showed preferential inactivation in one of the two maternal X-chromosomes. These results suggest that skewed X-inactivation in Klinefelter (47,XXY and 48,XXYY) patients may be common and could explain the wide range of mental deficiency and phenotypic abnormalities observed in this disorder. Further studies are warranted to examine the role of X-inactivation and genetic imprinting in Klinefelter patients.

Mice that overexpress Cu/Zn superoxide dismutase are resistant to allergen-induced changes in airway control

Within the respiratory epithelium of asthmatic patients, copper/zinc-containing superoxide dismutase (Cu/Zn SOD) is decreased. To address the hypothesis that lung Cu/Zn SOD protects against allergen-induced injury, wild-type and transgenic mice that overexpress human Cu/Zn SOD were either passively sensitized to ovalbumin (OVA) or actively sensitized by repeated airway exposure to OVA. Controls included nonsensitized wild-type and transgenic mice given intravenous saline or airway exposure to saline. After aerosol challenge to saline or OVA, segments of tracheal smooth muscle were obtained for in vitro analysis of neural control. In response to electrical field stimulation, wild-type sensitized mice challenged with OVA had significant increases in cholinergic reactivity. Conversely, sensitized transgenic mice challenged with OVA were resistant to changes in neural control. Stimulation of tracheal smooth muscle to elicit acetylcholine release showed that passively sensitized wild-type but not transgenic mice released more acetylcholine after OVA challenge. Function of the M(2) muscarinic autoreceptor was preserved in transgenic mice. These results demonstrate that murine airways with elevated Cu/Zn SOD were resistant to allergen-induced changes in neural control.

Noninvasive determination of fetal RhD status using fetal DNA in maternal serum and PCR

OBJECTIVE

Because prenatal testing of fetal RhD status by amniocentesis carries small yet finite risks to the fetus and mother, this study sought to determine whether fetal DNA in maternal serum could be used to detect fetal RhD status by polymerase chain reaction (PCR).

METHODS

A retrospective analysis was made of frozen serum specimens from 20 sensitized RhD-negative pregnant women (ranging from 15.0 to 36.0 weeks' gestation) who were confirmed by serology at birth to have been carrying RhD-positive fetuses. Eleven serum specimens from RhD-negative individuals served as controls. DNA was isolated from serum and used in two PCR-based methods to detect a 99 base pair (bp) DNA fragment specific for the RhD gene and a 113 bp fragment specific for the RhCE gene as control.

RESULTS

Overall, in 14 (70%) of 20 RhD-positive fetuses the 99 base pair RhD-specific PCR product was detected. There was no false positive detection among the 11 control serum specimens.

CONCLUSION

The results illustrate the ability to detect fetal RhD sequences in maternal serum of sensitized women. Moreover, the findings demonstrate that fetal single-gene disorders can be detected prenatally by using DNA isolated only from maternal serum.

Changes in the Caucasian male facial profile as depicted in fashion magazines during the twentieth century

The purposes of this study were to (1) measure changes in the young adult Caucasian male profile through time and (2) describe the male profile depicted in current fashion magazines. Profile photographs (n = 116) of male models collected from leading fashion magazines of the last 65 years were analyzed. They were reproduced as slides, and the images were scanned and projected onto a computer monitor. Soft tissue landmarks were digitized and the profiles were corrected for size differences. Six linear, nine angular, and three proportional parameters were measured. Anteroposterior lip position, lip curl, and vermilion area showed statistically significant correlations (r > or = 31, p < 0.01) with the progression of time. Other angular measurements and vertical facial proportions did not change significantly (r < or = 17, p > 0.05). The results showed that (1) the male profile depicted in fashion magazines has changed significantly with time and the changes were in the area of the lips; and (2) there was a trend of increasing lip protrusion, lip curl, and vermilion display. We conclude that similar to the female profile, the esthetic male profile has changed with time.

Prenatal diagnosis with use of fetal cells isolated from maternal blood: five-color fluorescent in situ hybridization analysis on flow-sorted cells for chromosomes X, Y, 13, 18, and 21

OBJECTIVE

Currently, prenatal diagnosis of chromosome abnormalities requires invasive techniques such as amniocentesis and chorionic villus sampling that carry small but finite risks of fetal loss. A noninvasive approach is to isolate fetal cells from maternal blood by flow sorting followed by genetic interphase analysis with fluorescence in situ hybridization. Because the ratio of fetal to maternal cells is relatively low after flow sorting and to detect 90% to 95% of fetal aneuploidies associated with serious birth defects, a 5-color fluorescent in situ hybridization strategy is necessary for simultaneous detection of chromosomes X, Y, 13, 18, and 21 in all flow-sorted nuclei recovered from a specimen.

STUDY DESIGN

Fetal nucleated red blood cells were isolated from maternal blood in 40 cases (10.4 to 27.0 weeks' gestation) by flow cytometry on the basis of positive selection of CD71+ (transferrin receptor), CD45-, and LDS751 staining. Each case was evaluated for 5-color fluorescent in situ hybridization efficiency by determining the percentage of flow-sorted nuclei containing 8 hybridization signals for chromosomes X, Y, 13, 18, and 21.

RESULTS

A total of 42,312 flow-sorted nuclei from maternal blood samples were analyzed. In 5 of 16 (31%) cases with a male fetus, 0.16% of nuclei scored were identified as fetal by the presence of 1 signal each for chromosomes X and Y. Fetal trisomy 21 nuclei were accurately detected in 2 cases with a female fetus, each of which was subsequently confirmed.

CONCLUSIONS

Five-color interphase fluorescent in situ hybridization analysis can be used to effectively analyze rare fetal aneuploid nuclei in enriched flow-sorted cells isolated from maternal blood.

Detection of chromosomal aneuploidy in endometriosis by multi-color fluorescence in situ hybridization (FISH)

Endometriosis affects 10-15% of women of reproductive age and is a common cause of infertility and pelvic pain. Although endometriosis is characterized by abnormal growth or turn-over of cells, the genetic changes involved remain unclear. We employed a multi-color fluorescence in situ hybridization (FISH) strategy to determine the incidence of somatic chromosomal numeric alterations in severe/late stage endometriosis. Using alpha-satellite sequence-specific DNA probes for chromosomes 7, 8, 11, 12, 16, 17, and 18, simultaneous two- and three-color FISH were performed to evaluate the frequency of monosomic, disomic, and trisomic cells in normal control and endometriotic tissue specimens. In one of four endometriosis samples studied, a significantly higher frequency of monosomy for chromosome 17 (14.8%, chi 2(4) = 53.3, P < 0.0001) and 16 (8.8%, chi 2(4) = 11.4, P < 0.05) was observed. An increased number of cells with chromosome 11 trisomy (14.8%, chi 2(4) = 96.2, P < 0.0001) were detected in a second case. In a third case, a distinct colony of nuclei with chromosome 16 monosomy (14.1%, chi 2(4) = 21.39, P < 0.005) was detected. Acquired chromosome-specific aneuploidy may be involved in endometriosis, reflecting clonal expansion of chromosomally abnormal cells. That candidate tumor suppressor genes and oncogenes have been mapped to chromosomes 11, 16, and 17 suggests that chromosomal loss or gain plays a role in the development and/or progression of endometriosis.

The use of a water extract from the bark of Choerospondias axillaris in the treatment of second degree burns

Burns are common in Vietnam, and because of economic constraints and limited resources for the import of appropriate treatments, the health authorities are obliged to rely on traditional herbal remedies. It is therefore essential to evaluate current drugs, one of which is the water extract of the bark of the tree Choerospondias axillaris. It has been used for many years in the Vietnam-Sweden hospital at Uong Bi in northern Vietnam. We assessed the efficacy of the remedy in an open, randomised controlled clinical trial, in which 20 patients with second degree burns were treated with the extract of the Choerospondias axillaris and 19 with saline gauze. The mean healing time was significantly shorter for patients treated with Choerospondias axillaris (11 days) compared with patients treated with saline gauze (17 days) (p < 0.01), and the number of wound infections was significantly lower in the Choerospondias axillaris group (7/20 compared with 16/19, p = 0.003). The bark extract was easy to apply and additional wound care was not usually necessary, while the treatment with saline gauze was laborious for both patients and staff and was much more expensive. The extract from Choerospondias axillaris is a convenient treatment for second degree burns in both children and adults.

Superoxide scavenging by Mn(II/III) tetrakis (1-methyl-4-pyridyl) porphyrin in mammalian cells

The superoxide dismutase mimic Mn(II/III) tetrakis (1-methyl-4-pyridyl) porphyrin (Mn(II/III)TMPyP) was examined for its superoxide radical (O2.-)-scavenging ability in cultured mammalian cells. Mn(III)TMPyP (< 5 microM) added to culture media relieved growth inhibition and decreased the inactivation of the O2(.-)-sensitive enzyme aconitase in cells exposed to the O2(.-)-generating phenazine pyocyanine. Treatment of cells with Mn(III)TMPyP did not measurably affect cellular O2.- production as revealed by rates of cyanide-resistant respiration with or without added pyocyanine. In contrast, Mn(II/III)TMPyP enhanced O2.- production in cells when the redox-active naphthoquinone menadione was present as measured by both increased cyanide-resistant respiration rates and aconitase inactivation. In vitro, Mn(II/III)TMPyP catalyzed the oxidation of ascorbate, and menadione enhanced this effect. Mn(III)TMPyP did not protect aconitase when O2.- production was elicited in mitochondria by antimycin A and the uncoupler carbonyl cyanide p-trifluoromethoxyphenylhydrazone. The results support a reductant-O2.-:oxidoreductase mechanism for O2.- scavenging by Mn(II/III)TMPyP in the mammalian cytosol as proposed for its action in Escherichia coli, but also indicate that Mn(II/III)TMPyP can either scavenge or produce O2.- in cells depending upon the prevailing pathways of Mn(II/III)TMPyP oxidation-reduction.

Detection of low-grade mosaicism in fetal cells isolated from maternal blood

Recovering and analysing fetal erythrocytes from maternal blood is being pursued for non-invasive prenatal genetic diagnosis. We report the observation of 46,XY/47,XXY mosaicism in fetal cells from a woman whose first-trimester chorionic villus sampling (CVS) initially showed only 46,XY. Only after exhaustive (500 cells) analysis were four XXY cells found in cultured villi.

Anti-CD3-induced anergy in cloned human Th0, Th1, and Th2 cells

In the mouse, activation of T cells by T cell receptor (TCR) crosslinking with anti-CD3 antibodies in the absence of a costimulatory signal induces Th1 but not Th2 cell anergy. Furthermore, anti-CD3 induces anergy of Th1- but not Th2-type lymphokine secretion in Th0 cells. This study was designed to determine whether this is also the case in man. Human rye grass allergen Lol p I-specific cloned CD4+ T helper cells of subtypes Th0, Th1, and Th2 were treated with immobilized anti-CD3. The cells were rested for 4 days and then activated under optimal conditions with antigen and antigen-presenting cells (APCs). Cell proliferation and IL-2, IFN-gamma, and IL-4 secretion was determined to test for the anergic state. The initial anti-CD3 treatment induced cell proliferation, IL-2, IFN-gamma, and/or IL-4 secretion by T cells of all three subsets which was followed by an anergic state in Th0, Th1, and Th2 cells as shown by a 51 to > 94% decrease in cell proliferation and IFN-gamma and/or IL-4 secretion after subsequent APC and Lol p I activation. Addition of IL-2 or IL-4 during anti-CD3 treatment of the cells did not prevent unresponsiveness. However, the addition of IL-2 but not IL-4 during APC and Lol p I stimulation partially reversed the anergic state. These data demonstrate that, contrary to the mouse, cloned T cells of all three human T helper cell subtypes are anergized by anti-CD3 TCR activation in the absence of costimulatory signals. The fact that human Th2 cells can be anergized may be important for the development of new treatments in Th2-mediated allergic disorders.

Aconitase is a sensitive and critical target of oxygen poisoning in cultured mammalian cells and in rat lungs

The effect of hyperoxia on activity of the superoxide-sensitive citric acid cycle enzyme aconitase was measured in cultured human epithelial-like A549 cells and in rat lungs. Rapid and progressive loss of > 80% of the aconitase activity in A549 cells was seen during a 24-hr exposure to a PO2 of 600 mmHg (1 mmHg = 133 Pa). Inhibition of mitochondrial respiratory capacity correlated with loss of aconitase activity in A549 cells exposed to hyperoxia, and this effect could be mimicked by fluoroacetate (or fluorocitrate), a metabolic poison of aconitase. Exposure of rats to an atmospheric PO2 of 760 mmHg or 635 mmHg for 24 hr caused respective 73% and 61% decreases in total lung aconitase activity. We propose that early inactivation of aconitase and inhibition of the energy-producing and biosynthetic reactions of the citric acid cycle contribute to the sequelae of lung damage and edema seen during exposure to hyperoxia.

Estimates of aneuploidy using multicolor fluorescence in situ hybridization on human sperm

Single color fluorescence in situ hybridization (FISH) has been utilized on sperm to estimate nondisjunction rates for chromosomes 1, 12, 15, 16, X and Y. Using single-color FISH, one cannot distinguish nonhybridization from nullisomy nor disomy from diploidy. In order to provide an internal control, a multicolor FISH strategy was employed. Satellite probes specific for 13 human chromosomes were used on multiple semen samples from two normal donors. Two or three probes were hybridized simultaneously and scored by two independent observers. Over all experiments, 40,641 sperm were analyzed. The majority of autosomes had no significant difference in aneuploidy between chromosomes or between donors. However, a significant difference was observed for chromosome 18 between donors (chi 2(2) = 7.078, 0.025 < P < 0.05). Additionally, no significant difference was found between donors for sex chromosome aneuploidy. The frequency of sex chromosome aneuploidy was similar to that seen in paternally derived 47,XXY and 47,XYY conceptuses. Furthermore, 0.15% of sperm were found to be diploid. Based on the results of this study, as much as 19% of all sperm may be chromosomally abnormal. This method proved to be useful for determining aneuploidy of human chromosomes in sperm and valuable in exploring whether individual differences of nondisjunction exist.

Association between leucocyte group-5a antigen and acute lymphoblastic leukaemia

Leucocyte group 5 has two dominant alleles (5a and 5b) which segregate independently of the major histocompatibility complex. The group-5 system was studied in a Caucasian population of controls and patients with acute lymphoblastic leukaemia. The 5a gene frequency was 0-09 in 72 controls and 0-38 in 39 patients with acute lymphoblastic leukaemia (p less than 0-001). 15 patients with acute myelogenous leukaemia and 12 patients with aplastic anaemia had 5a and 5b frequencies similar to those seen in the control population. It is concluded that 5a or a closely linked gene is involved in susceptibility to acute lymphoblastic leukaemia.