Genome-wide meta-analysis increases to 71 the number of confirmed Crohn's disease susceptibility loci

We undertook a meta-analysis of six Crohn's disease genome-wide association studies (GWAS) comprising 6,333 affected individuals (cases) and 15,056 controls and followed up the top association signals in 15,694 cases, 14,026 controls and 414 parent-offspring trios. We identified 30 new susceptibility loci meeting genome-wide significance (P < 5 × 10⁻⁸). A series of in silico analyses highlighted particular genes within these loci and, together with manual curation, implicated functionally interesting candidate genes including SMAD3, ERAP2, IL10, IL2RA, TYK2, FUT2, DNMT3A, DENND1B, BACH2 and TAGAP. Combined with previously confirmed loci, these results identify 71 distinct loci with genome-wide significant evidence for association with Crohn's disease.

European Society for Pediatric Gastroenterology, Hepatology, and Nutrition guidelines for the diagnosis of coeliac disease

OBJECTIVE

Diagnostic criteria for coeliac disease (CD) from the European Society for Paediatric Gastroenterology, Hepatology, and Nutrition (ESPGHAN) were published in 1990. Since then, the autoantigen in CD, tissue transglutaminase, has been identified; the perception of CD has changed from that of a rather uncommon enteropathy to a common multiorgan disease strongly dependent on the haplotypes human leukocyte antigen (HLA)-DQ2 and HLA-DQ8; and CD-specific antibody tests have improved.

METHODS

A panel of 17 experts defined CD and developed new diagnostic criteria based on the Delphi process. Two groups of patients were defined with different diagnostic approaches to diagnose CD: children with symptoms suggestive of CD (group 1) and asymptomatic children at increased risk for CD (group 2). The 2004 National Institutes of Health/Agency for Healthcare Research and Quality report and a systematic literature search on antibody tests for CD in paediatric patients covering the years 2004 to 2009 was the basis for the evidence-based recommendations on CD-specific antibody testing.

RESULTS

In group 1, the diagnosis of CD is based on symptoms, positive serology, and histology that is consistent with CD. If immunoglobulin A anti-tissue transglutaminase type 2 antibody titers are high (>10 times the upper limit of normal), then the option is to diagnose CD without duodenal biopsies by applying a strict protocol with further laboratory tests. In group 2, the diagnosis of CD is based on positive serology and histology. HLA-DQ2 and HLA-DQ8 testing is valuable because CD is unlikely if both haplotypes are negative.

CONCLUSIONS

The aim of the new guidelines was to achieve a high diagnostic accuracy and to reduce the burden for patients and their families. The performance of these guidelines in clinical practice should be evaluated prospectively.

CD4+ count-guided interruption of antiretroviral treatment

BACKGROUND

Despite declines in morbidity and mortality with the use of combination antiretroviral therapy, its effectiveness is limited by adverse events, problems with adherence, and resistance of the human immunodeficiency virus (HIV).

METHODS

We randomly assigned persons infected with HIV who had a CD4+ cell count of more than 350 per cubic millimeter to the continuous use of antiretroviral therapy (the viral suppression group) or the episodic use of antiretroviral therapy (the drug conservation group). Episodic use involved the deferral of therapy until the CD4+ count decreased to less than 250 per cubic millimeter and then the use of therapy until the CD4+ count increased to more than 350 per cubic millimeter. The primary end point was the development of an opportunistic disease or death from any cause. An important secondary end point was major cardiovascular, renal, or hepatic disease.

RESULTS

A total of 5472 participants (2720 assigned to drug conservation and 2752 to viral suppression) were followed for an average of 16 months before the protocol was modified for the drug conservation group. At baseline, the median and nadir CD4+ counts were 597 per cubic millimeter and 250 per cubic millimeter, respectively, and 71.7% of participants had plasma HIV RNA levels of 400 copies or less per milliliter. Opportunistic disease or death from any cause occurred in 120 participants (3.3 events per 100 person-years) in the drug conservation group and 47 participants (1.3 per 100 person-years) in the viral suppression group (hazard ratio for the drug conservation group vs. the viral suppression group, 2.6; 95% confidence interval [CI], 1.9 to 3.7; P<0.001). Hazard ratios for death from any cause and for major cardiovascular, renal, and hepatic disease were 1.8 (95% CI, 1.2 to 2.9; P=0.007) and 1.7 (95% CI, 1.1 to 2.5; P=0.009), respectively. Adjustment for the latest CD4+ count and HIV RNA level (as time-updated covariates) reduced the hazard ratio for the primary end point from 2.6 to 1.5 (95% CI, 1.0 to 2.1).

CONCLUSIONS

Episodic antiretroviral therapy guided by the CD4+ count, as used in our study, significantly increased the risk of opportunistic disease or death from any cause, as compared with continuous antiretroviral therapy, largely as a consequence of lowering the CD4+ cell count and increasing the viral load. Episodic antiretroviral therapy does not reduce the risk of adverse events that have been associated with antiretroviral therapy. (ClinicalTrials.gov number, NCT00027352 [ClinicalTrials.gov].).

Meta-analysis identifies 29 additional ulcerative colitis risk loci, increasing the number of confirmed associations to 47

Genome-wide association studies and candidate gene studies in ulcerative colitis have identified 18 susceptibility loci. We conducted a meta-analysis of six ulcerative colitis genome-wide association study datasets, comprising 6,687 cases and 19,718 controls, and followed up the top association signals in 9,628 cases and 12,917 controls. We identified 29 additional risk loci (P < 5 × 10(-8)), increasing the number of ulcerative colitis-associated loci to 47. After annotating associated regions using GRAIL, expression quantitative trait loci data and correlations with non-synonymous SNPs, we identified many candidate genes that provide potentially important insights into disease pathogenesis, including IL1R2, IL8RA-IL8RB, IL7R, IL12B, DAP, PRDM1, JAK2, IRF5, GNA12 and LSP1. The total number of confirmed inflammatory bowel disease risk loci is now 99, including a minimum of 28 shared association signals between Crohn's disease and ulcerative colitis.

Genome-wide association study of CNVs in 16,000 cases of eight common diseases and 3,000 shared controls

Copy number variants (CNVs) account for a major proportion of human genetic polymorphism and have been predicted to have an important role in genetic susceptibility to common disease. To address this we undertook a large, direct genome-wide study of association between CNVs and eight common human diseases. Using a purpose-designed array we typed approximately 19,000 individuals into distinct copy-number classes at 3,432 polymorphic CNVs, including an estimated approximately 50% of all common CNVs larger than 500 base pairs. We identified several biological artefacts that lead to false-positive associations, including systematic CNV differences between DNAs derived from blood and cell lines. Association testing and follow-up replication analyses confirmed three loci where CNVs were associated with disease-IRGM for Crohn's disease, HLA for Crohn's disease, rheumatoid arthritis and type 1 diabetes, and TSPAN8 for type 2 diabetes-although in each case the locus had previously been identified in single nucleotide polymorphism (SNP)-based studies, reflecting our observation that most common CNVs that are well-typed on our array are well tagged by SNPs and so have been indirectly explored through SNP studies. We conclude that common CNVs that can be typed on existing platforms are unlikely to contribute greatly to the genetic basis of common human diseases.

Why do people sue doctors? A study of patients and relatives taking legal action

To examine the reasons patients and their relatives take legal action, we surveyed 227 patients and relatives who were taking legal action through five firms of plaintiff medical negligence solicitors. Over 70% of respondents were seriously affected by incidents that gave rise to litigation with long-term effects on work, social life, and family relationships. Intense emotions were aroused and continued to be felt for a long time. The decision to take legal action was determined not only by the original injury, but also by insensitive handling and poor communication after the original incident. Where explanations were given, less than 15% were considered satisfactory. Four main themes emerged from the analysis of reasons for litigation: concern with standards of care--both patients and relatives wanted to prevent similar incidents in the future; the need for an explanation--to know how the injury happened and why; compensation--for actual losses, pain and suffering or to provide care in the future for an injured person; and accountability--a belief that the staff or organisation should have to account for their actions. Patients taking legal action wanted greater honesty, an appreciation of the severity of the trauma they had suffered, and assurances that lessons had been learnt from their experiences. A no-fault compensation system, however well intended, would not address all patients' concerns. If litigation is viewed solely as a legal and financial problem, many fundamental issues will not be addressed or resolved.

Late presentation of HIV infection: a consensus definition

OBJECTIVES

Across Europe, almost a third of individuals infected with HIV do not enter health care until late in the course of their infection. Surveillance to identify the extent to which late presentation occurs remains inadequate across Europe and is further complicated by the lack of a common clinical definition of late presentation. The objective of this article is to present a consensus definition of late presentation of HIV infection.

METHODS

Over the past year, two initiatives have moved towards a harmonized definition. In spring 2009, they joined efforts to identify a common definition of what is meant by a 'late-presenting' patient.

RESULTS

Two definitions were agreed upon, as follows. Late presentation: persons presenting for care with a CD4 count below 350 cells/μL or presenting with an AIDS-defining event, regardless of the CD4 cell count. Presentation with advanced HIV disease: persons presenting for care with a CD4 count below 200 cells/μL or presenting with an AIDS-defining event, regardless of the CD4 cell count.

CONCLUSION

The European Late Presenter Consensus working group believe it would be beneficial if all national health agencies, institutions, and researchers were able to implement this definition (either on its own or alongside their own preferred definition) when reporting surveillance or research data relating to late presentation of HIV infection.

Risk of lipodystrophy in HIV-1-infected patients treated with protease inhibitors: a prospective cohort study

BACKGROUND

Risk factors for lipodystrophy in patients infected with HIV-1 treated with highly active antiretroviral therapy (HAART) containing HIV-1 protease inhibitors are poorly understood. We aimed to identify the risk factors for lipodystrophy in antiretroviral-naive HIV-1-infected adults on HAART.

METHODS

Moderate or severe body-fat changes were clinically assessed and categorised as subcutaneous lipoatrophy, central obesity, or both, in all consecutive antiretroviral-naïve HIV-1-infected adults who began HAART with two nucleoside reverse transcriptase inhibitors plus at least one protease inhibitor from October, 1996, to September, 1999. A person-years analysis was used to calculate the incidence of types of lipodystrophy, and Cox proportional hazards models were used to describe the univariate and multivariate factors associated with progression to any lipodystrophy.

FINDINGS

After a median follow-up of 18 months, 85 (17%) of the 494 patients developed some type of lipodystrophy. The incidences of any lipodystrophy, lipodystrophy with subcutaneous lipoatrophy, and lipodystrophy with central obesity were 11.7 (95% CI 9.2-14.2), 9.2 (7.0-11.4), and 7.7 (5.7-9.7) per 100 patient-years. An increased risk for any lipodystrophy was found among women as compared with men (relative hazard 1.87 [1.07-3.28]), heterosexuals (2.86 [1.50-5.48]), and homosexuals (2.17 [1.07-4.42]) as compared with intravenous drug users, with increasing age (1.33 per 10 years older [1.08-1.62]), and with the duration of exposure to antiretroviral therapy (1.57 per 6 months extra [1.30-1.88]) but not with any individual antiretroviral agent. The factors associated with an increased risk for lipodystrophy with subcutaneous lipoatrophy or lipodystrophy with central obesity were very similar to those associated with any lipodystrophy. The duration of indinavir use may represent an additional contribution for the development of lipodystrophy with central obesity (1.26 per 6 months extra [0.99-1.60]); p=0.064).

INTERPRETATION

Risk factors associated with development of any lipodystrophy, lipodystrophy with subcutaneous lipoatrophy, and tipodystrophy with central obesity in patients infected with HIV-1 who were receiving HAART containing protease inhibitors are multifactorial and overlapping, and cannot be exclusively ascribed to the duration of exposure to an particular antiretroviral agent.

Interleukin-2 therapy in patients with HIV infection

BACKGROUND

Used in combination with antiretroviral therapy, subcutaneous recombinant interleukin-2 raises CD4+ cell counts more than does antiretroviral therapy alone. The clinical implication of these increases is not known.

METHODS

We conducted two trials: the Subcutaneous Recombinant, Human Interleukin-2 in HIV-Infected Patients with Low CD4+ Counts under Active Antiretroviral Therapy (SILCAAT) study and the Evaluation of Subcutaneous Proleukin in a Randomized International Trial (ESPRIT). In each, patients infected with the human immunodeficiency virus (HIV) who had CD4+ cell counts of either 50 to 299 per cubic millimeter (SILCAAT) or 300 or more per cubic millimeter (ESPRIT) were randomly assigned to receive interleukin-2 plus antiretroviral therapy or antiretroviral therapy alone. The interleukin-2 regimen consisted of cycles of 5 consecutive days each, administered at 8-week intervals. The SILCAAT study involved six cycles and a dose of 4.5 million IU of interleukin-2 twice daily; ESPRIT involved three cycles and a dose of 7.5 million IU twice daily. Additional cycles were recommended to maintain the CD4+ cell count above predefined target levels. The primary end point of both studies was opportunistic disease or death from any cause.

RESULTS

In the SILCAAT study, 1695 patients (849 receiving interleukin-2 plus antiretroviral therapy and 846 receiving antiretroviral therapy alone) who had a median CD4+ cell count of 202 cells per cubic millimeter were enrolled; in ESPRIT, 4111 patients (2071 receiving interleukin-2 plus antiretroviral therapy and 2040 receiving antiretroviral therapy alone) who had a median CD4+ cell count of 457 cells per cubic millimeter were enrolled. Over a median follow-up period of 7 to 8 years, the CD4+ cell count was higher in the interleukin-2 group than in the group receiving antiretroviral therapy alone--by 53 and 159 cells per cubic millimeter, on average, in the SILCAAT study and ESPRIT, respectively. Hazard ratios for opportunistic disease or death from any cause with interleukin-2 plus antiretroviral therapy (vs. antiretroviral therapy alone) were 0.91 (95% confidence interval [CI], 0.70 to 1.18; P=0.47) in the SILCAAT study and 0.94 (95% CI, 0.75 to 1.16; P=0.55) in ESPRIT. The hazard ratios for death from any cause and for grade 4 clinical events were 1.06 (P=0.73) and 1.10 (P=0.35), respectively, in the SILCAAT study and 0.90 (P=0.42) and 1.23 (P=0.003), respectively, in ESPRIT.

CONCLUSIONS

Despite a substantial and sustained increase in the CD4+ cell count, as compared with antiretroviral therapy alone, interleukin-2 plus antiretroviral therapy yielded no clinical benefit in either study. (ClinicalTrials.gov numbers, NCT00004978 [ESPRIT] and NCT00013611 [SILCAAT study].)

Association between serum albumin and mortality from cardiovascular disease, cancer, and other causes

In a prospective study of 7735 middle-aged British men (British Regional Heart Study) 660 died during an average follow-up period of 9.2 years. There was a marked increase in mortality rate with decreasing serum albumin concentrations that persisted even after adjustment for age, social class, town of residence, cigarette smoking, serum total cholesterol, systolic blood pressure, serum total calcium, and forced expiratory volume in 1 s. When serum albumin concentration was less than 40 g/l, the mortality rate was 23/1000 per year compared with 4/1000 per year for a concentration equal to or above 48 g/l. A similar pattern was observed for cardiovascular, cancer, and other deaths. The associations persisted for cardiovascular disease and cancer even when deaths within the first five years of follow-up were excluded. These results must be interpreted with caution since there was no prior hypothesis concerning serum albumin. However, the strength of the association between serum albumin and mortality seems to be comparable with that for cigarette smoking.

Treatment of life-threatening digitalis intoxication with digoxin-specific Fab antibody fragments: experience in 26 cases

Purified Fab fragments of digoxin-specific antibodies obtained from sheep were used to treat 26 patients with advanced, life-threatening digoxin (23 cases) or digitoxin (3 cases) toxicity. These patients had advanced cardiac arrhythmias, and in some cases hyperkalemia, which were resistant to conventional treatment. All patients had an initial favorable response to doses of Fab fragments calculated (in most cases) to be equivalent, on a molar basis, to the amount of cardiac glycoside in the patient's body. In four patients treated after prolonged hypotension and low cardiac output, death ensued from cerebral or myocardial hypoperfusion. In one case the available Fab fragment supply was inadequate to reverse a massive suicidal ingestion of digoxin, and the patient died after recurrent ventricular arrhythmias. In the remaining 21 patients, cardiac rhythm disturbances and hyperkalemia were rapidly reversed, and full recovery ensued. There were no adverse reactions to the treatment. We conclude that the use of purified digoxin-specific Fab fragments is a safe and effective means to reverse advanced, life-threatening digitalis intoxication.

Prospective randomised trial of chemotherapy given before radiotherapy in childhood medulloblastoma. International Society of Paediatric Oncology (SIOP) and the (German) Society of Paediatric Oncology (GPO): SIOP II

In a multicentre randomised clinical trial 364 children with biopsy proven medulloblastoma were randomly assigned to receive or not pre-radiotherapy chemotherapy. Children with total or subtotal removal of the tumour, no evidence of invasive brain stem involvement, and no evidence of metastatic disease either within or without the cranium were designated "low risk", those with gross residual tumour, evidence of invasive brain stem involvement or metastases in the central nervous system were designated "high risk". All children were prescribed 55 Gy to the tumour bearing area. "Low risk" children could be randomised to "standard" radiotherapy 35 Gy to the craniospinal axis or "reduced" dose 25 Gy to the craniospinal axis. Chemotherapy consisted of vincristine, procarbazine, and methotrexate given in a 6-week module before radio-therapy, and for "high risk" children, vincristine and CCNU given after radiotherapy. No benefit for the receipt of pre-radiotherapy chemotherapy could be demonstrated for any group. In addition, a negative interaction was observed between the receipt of the chemotherapy and reduced dose radio-therapy with a particularly poor outcome being observed in this group of children.

Hepatotoxicity in HIV-1-infected patients receiving nevirapine-containing antiretroviral therapy

OBJECTIVES

To assess the incidence and risk factors for hepatotoxicity associated with nevirapine.

DESIGN

A prospective cohort study in a teaching and referral hospital involving all consecutive patients who were prescribed a nevirapine-containing antiretroviral regimen between September 1997 and May 2000.

METHOD

Cutaneous and hepatic adverse reactions and clinical hepatitis were assessed. Blood analysis including plasma HIV-1 RNA CD4 cell counts, liver chemistry tests, and serology for hepatitis B and C viruses. Hepatotoxicity was defined as an increase of at least threefold in serum alanine aminotransferase or aspartate aminotransferase levels compared with baseline values.

RESULTS

Of a total of 610 patients, 82 (13.4%) were antiretroviral naive when commencing nevirapine, and 46.2 and 8.9% were coinfected with hepatitis C and B viruses, respectively. Median duration of exposure to nevirapine was 8.7 months (interquartile range 3.4--14.3). Hepatotoxicity developed in 76 (12.5%), an incidence of 13.1/100 person-years. Kaplan--Meier estimated incidence of hepatotoxicity at 3, 6 and 12 months was 3.7, 9.7 and 20.1%, respectively. In seven (1.1%) patients, hepatotoxicity was associated with clinical hepatitis, which was reversible upon discontinuation of therapy. Multivariate analysis identified the duration of prior exposure to antiretroviral drugs, hepatitis C virus, and higher baseline levels of alanine aminotransferase as independent risk factors for hepatotoxicity.

CONCLUSIONS

Hepatotoxicity but not clinical hepatitis was common in HIV-1-infected patients receiving nevirapine-containing regimens and the incidence steadily increased over time. Prolonged exposure to any antiretroviral therapy, coinfection with hepatitis C virus and abnormal baseline levels of alanine aminotransferase identified patients at a higher risk.

Stabilization of poly-L-lysine/DNA polyplexes for in vivo gene delivery to the liver

We are developing a self-assembling non-viral in vivo gene delivery vehicle based on poly-l-lysine and plasmid DNA. We have characterized poly-l-lysines of different chain lengths for DNA condensation and strength of DNA binding. Poly-l-lysine chains >20 residues bound DNA efficiently in physiological saline, while shorter chains did not. Attachment of asialoorosomucoid to PLL increased the PLL chain length required for efficient DNA binding in saline and for efficient DNA condensation. By electron microscopy, poly-l-lysine/DNA polyplexes appeared as toroids 25-50 nm in diameter or rods 40-80 nm long; conjugation of asialoorosomucoid to the polylysine component increased the size of resulting polyplexes to 50-90 nm. In water, poly-l-lysine and asialoorosomucoid-PLL polyplexes have effective diameters of 46 and 87.6 nm, respectively. Polyplexes containing only poly-l-lysine and DNA aggregated in physiological saline at all charge ratios and aggregated at neutral charge ratios in water. Attachment of asialoorosomucoid lessened, but did not eliminate, the aggregation of PLL polyplexes, and did not result in efficient delivery of polyplexes to hepatocytes. Conjugation of polyethylene glycol to poly-l-lysine sterically stabilized resulting polyplexes at neutral charge ratios by shielding the surfaces. For efficient in vivo gene delivery, polyplexes will need to be sterically stabilized to prevent aggregation and interaction with serum components.

Pretreatment prognostic factors for children with hepatoblastoma-- results from the International Society of Paediatric Oncology (SIOP) study SIOPEL 1

The aim of this study was to investigate the prognostic significance of pretreatment patient and tumour characteristics for overall (OS) and event-free (EFS) survival in 154 children affected by hepatoblastoma (HB) in the first prospective liver tumour study run by the International Society of Paediatric Oncology. The pretreatment characteristics studied were age, alpha-fetoprotein, platelet count, histology; from radiology: intrahepatic tumour extension (PRETEXT), lung metastases, enlarged hilar lymph nodes, vena cava or extrahepatic vena porta tumour extension and tumour focality. Five-year OS was 75% (95% confidence interval (CI) 68-82%) and EFS 66% (95% CI 59-74%). Both were univariately associated with PRETEXT and the presence of metastases. Additionally tumour focality and enlargement of hilar lymph nodes at diagnosis were univariately associated with EFS. In multivariate analysis, PRETEXT was the only predictor of OS; PRETEXT and metastases were predictors of EFS. There is a need to investigate further these factors to confirm their validity.

Aggregative adherence fimbria II, a second fimbrial antigen mediating aggregative adherence in enteroaggregative Escherichia coli

Enteroaggregative Escherichia coli (EAEC) has been implicated as an agent of pediatric diarrhea in the developing world. We have shown previously that EAEC adheres to HEp-2 cells by virtue of a plasmid-encoded fimbrial adhesin designated aggregative adherence fimbria I (AAF/I), the genes for which have been cloned and sequenced. However, not all EAEC strains express AAF/I. Using TnphoA mutagenesis, we have characterized a novel fimbria (designated AAF/II) which mediates HEp-2 adherence of the human-pathogenic strain 042. AAF/II is 5 nm in diameter and does not bind AAF/I antiserum, as determined by immunogold transmission electron microscopy. TnphoA identified a gene (designated aafA) which bears significant homology to aggA, the fimbrial subunit of AAF/I (25% identity and 47% similarity at the amino acid level). When hyperexpressed and purified by polyhistidine tagging, the AafA protein assembled into 5-nm-diameter filaments which bound anti-AAF/II antiserum. The cloned aafA gene complemented a mutation in the aggA gene to confer fimbrial expression from the AAF/I gene cluster, manifesting phenotypes characteristic of AAF/II but not AAF/I. The aafA mutant did not adhere to human intestinal tissue in culture, suggesting a role for AAF/II in intestinal colonization. By using DNA probes for AAF/I and AAF/II derived from fimbrial biosynthesis genes, we show that AAF/I and AAF/II are each found in only a minority of EAEC strains, suggesting that still more EAEC adhesins exist. Our data suggest that AAF adhesins represent a new family of fimbrial adhesins which mediate aggregative adherence in EAEC.

Cisplatin, doxorubicin, and delayed surgery for childhood hepatoblastoma: a successful approach--results of the first prospective study of the International Society of Pediatric Oncology

PURPOSE

Hepatoblastoma (HB) is a rare malignant liver tumor which occurs almost exclusively in childhood. In the 1970s, survival was approximately 20% to 30%. Since the introduction of cisplatin (PLA) and doxorubicin (DO) into the chemotherapy regimens used to treat these patients, the survival rate has improved dramatically. In most recent studies, primary surgery preceded chemotherapy. In this study by the liver group of the International Society of Pediatric Oncology the aim was to improve survival and reduce operative morbidity and mortality by using preoperative chemotherapy.

PATIENTS AND METHODS

After biopsy and assessment of pretreatment extent of disease all patients were treated with continuous 24-hour intravenous infusion of PLA 80 mg/m(2) followed by DO 60 mg/m(2) over 48 hours (PLADO). After four courses of this chemotherapy, patients were reassessed. Where possible, the primary tumor was resected and treatment completed with two more courses of chemotherapy.

RESULTS

One hundred fifty-four patients were registered in the study, and 138 received preoperative chemotherapy. One hundred thirteen (82%) showed a partial response with tumor shrinkage and serial decrease of serum alpha-fetoprotein levels. One hundred fifteen patients had delayed surgery, and 106 (including six with liver transplants) had complete resection of primary tumor. Five-year event-free survival was 66%, and overall survival was 75%.

CONCLUSION

This study demonstrates that international collaboration on a large scale is feasible. The toxicity of chemotherapy and morbidity of surgery were acceptable and the overall survival gratifyingly high. We now regard PLADO chemotherapy and delayed surgery to be the best available treatment for children with HB. Other treatment programs should be measured against this standard.

Virological and immunological effects of treatment interruptions in HIV-1 infected patients with treatment failure

OBJECTIVE

To analyse the immunological and virological effects of treatment interruptions in HIV-1-infected patients with treatment failure and multidrug-resistant virus.

METHODS

Drug susceptibility was assessed using Antivirogram and genotypic analysis was based on population and clonal sequencing for 48 patients who had interrupted treatment (> or = 2 months).

RESULTS

Treatment interruption resulted in viral load increases (mean 0.7 log 10 copies/ ml; P = 0.0001) and CD4 cell count decreases (mean 89 x 10(6) cells/l; P = 0.0001). A complete shift to wild-type virus at the phenotypic, genotypic and clonal level was observed in 28/45 patients. These patients differed from those that did not show a shift to wild type in baseline CD4 cell counts (192 versus 59 x 10(6) cells/l; P= 0.007) and in the relationship between baseline viral load and CD4 cell count (no correlation versus a significant negative correlation; P= 0.008). Response to re-initiation of treatment fell with increasing viral load [relative hazard (RH) 0.33; P= 0.001] and with increasing total number of drugs with reduced susceptibility (RH 0.51; P = 0.0003); it improved with the number of new drugs received (RH 2.12; P = 0.0002) and a shift to wild type (RH 5.22, P = 0.006).

CONCLUSIONS

Changes in surrogate markers suggest that treatment provided benefit in spite of virological failure and resistant virus. Although patients with a shift to wildtype virus responded better in the short term to treatment re-initiation, the long-term effects are not known and the risk of immune deterioration needs to be carefully considered.

An international field study of the reliability and validity of a disease-specific questionnaire module (the QLQ-MY20) in assessing the quality of life of patients with multiple myeloma

AIM

To test the reliability, validity and sensitivity of the European Organisation for Research and Treatment of Cancer (EORTC) QLQ-MY24 questionnaire, designed to assess the quality of life of myeloma patients with the QLQ-C30.

METHODS

The study was carried out through the EORTC Quality of Life Group using clinical trials in seven countries. All trials used the QLQ-C30 and QLQ-MY24 at baseline and a follow-up timepoint.

RESULTS

Two hundred and forty patients participated. The questionnaires were acceptable to patients. The hypothesised scale structure (disease symptoms, side-effects, body image and future perspective) was confirmed by multi-trait scaling, internal consistency and correlation analysis. Most scales demonstrated sensitivity to change and discriminated between clinically different patients. The social support scale (4 items) was removed due to observed ceiling effects.

CONCLUSION

The final questionnaire contains 20 items, QLQ-MY20, and is a reliable and valid instrument recommended for use with the QLQ-C30 in myeloma patients.

Factors associated with a reduced CD4 lymphocyte count response to HAART despite full viral suppression in the EuroSIDA study

OBJECTIVES

To describe the prevalence and risk factors of poor CD4 count rise despite a good virological response on highly active antiretroviral treatment (HAART).

METHODS

The patients from the EuroSIDA study who started HAART with a baseline CD4 count of <350 cells/microL and where all viral load (pVL) measures remained below 500 HIV-1 RNA copies/mL between 6 and 12 months after the start of HAART were included. The risk factors for poor CD4 count rise were analyzed by multiple regression.

RESULTS

Seven hundred and eighty patients were included. A low CD4 count response was observed in 225 patients (29%). The risk factors for this condition were older age, lower CD4 count at baseline, higher increase from the nadir to baseline CD4 count and lower pVL at baseline. Patients taking > or =one drug from each of the three antiviral classes were more likely to have a good CD4 response but a minority of the study participants was taking this treatment regimen (3.1%) and the confidence interval was large.

CONCLUSIONS

A poor immune reconstitution despite a good virological control is frequent after initiation of HAART among patients with a baseline CD4 count of <350 cells/microL. The underlying mechanisms leading to this condition seems mainly driven by the age and the baseline immunological and virological status of the patients.

Short-term risk of AIDS according to current CD4 cell count and viral load in antiretroviral drug-naive individuals and those treated in the monotherapy era

BACKGROUND

One key piece of information required when deciding whether to initiate antiretroviral therapy is the risk of AIDS before the next clinic visit. Information on the short-term (6-month) risk of AIDS according to the current viral load and CD4 cell count in untreated individuals and those treated in the zidovudine monotherapy era (i.e., pre-September 1995), especially in those with CD4 cell count > 200 x 10 cells/l, is lacking.

METHODS

Risk of AIDS was assessed in 3226 subjects with viral load and CD4 cell count known before initiation of antiretroviral therapy or during the zidovudine monotherapy era. These were from CASCADE Collaboration in which data from 20 cohorts of individuals with known dates of seroconversion to HIV, based in clinics in Europe and Australia, have been combined.

RESULTS

During a total 5126.0 person-years of follow-up, 219 individuals developed AIDS. In those with current CD4 cell count < 200 x 10 cells/l, 6-month risks were 4.9, 12.7, 17.7 and 22.4% for viral load groups < 10 000, 10 000-29 999, 30 000- 99 999 and > or = 100 000 copies/ml, respectively. For CD4 cell counts 200-349 x 10 cells/l risks were 0.5, 1.6, 3.2 and 4.7%, respectively, for the four viral load groups while the corresponding values for group with CD4 cell count > or = 350 x 10 cells/l were 0.2%, 0.5%, 0.9% and 2.2%, respectively. Results were similar when analysis was restricted to those with no antiretroviral drug experience. Older people had a higher risk of AIDS for a given CD4 cell count and viral load than younger people.

CONCLUSION

Combined with consideration of other issues, these estimates should prove useful information when deciding whether to initiate antiretroviral therapy in HIV-infected individuals.

Confirming testosterone administration by isotope ratio mass spectrometric analysis of urinary androstanediols

A gas chromatographic combustion isotope ratio mass spectrometric (GC/C/IRMS) method was used for studying the incorporation of exogenous testosterone enanthate into excreted urinary 5 alpha- and 5 beta-androstane-3 alpha, 17 beta-diols. A multistep but straightforward work-up procedure produced a simple GC chromatogram of urinary steroid acetates composed principally of two androstanediols and pregnanediol. It is anticipated that such a method may form the basis of a doping control test for testosterone that could be used as a primary method during major sporting events or alternatively as a verification technique. Urine samples from five individuals were collected before and after administration of testosterone enanthate (250 mg). The delta 13C0/1000 value of andro-stanediols was around -26 to -28 during the baseline period and decreased to about -29 to -30 in the days following synthetic testosterone administration. One of the other major steroids in the chromatogram, pregnanediol, was utilized as the "internal standard," because its delta 13C0/1000 values did not markedly change following testosterone administration, remaining at -25 to -27. In all subjects studied, the delta 13C0/1000 values for androstanediols were reduced sufficiently over 8 days to confirm administration of synthetic testosterone. Although steroids isolated from urine of normal individuals from 12 different countries gave values between -24 and -28, this seemed not to be related to nationality or region. The most likely variable is the proportion of plants with low and high carbon 13 content in the diet. This variable is likely to be more affected by individual food preferences than broad ethnic food divisions. In this paper, we propose a ratio of delta 13C0/1000 for androstanediols to pregnanediol as a useful discriminant of testosterone misuse, a value above 1.1:1.0 being indicative of such misuse. The work-up procedure was designed for batch analysis and to use only simple techniques, rather than employ further instrumentation, such as high-performance liquid chromatography (HPLC), in purifying steroids for GC/C/IRMS.

Multiple sequence alignment in phylogenetic analysis

Multiple sequence alignment is discussed in light of homology assessments in phylogenetic research. Pairwise and multiple alignment methods are reviewed as exact and heuristic procedures. Since the object of alignment is to create the most efficient statement of initial homology, methods that minimize nonhomology are to be favored. Therefore, among all possible alignments, the one that satisfies the phylogenetic optimality criterion the best should be considered the best alignment. Since all homology statements are subject to testing and explanation this way, consistency of optimality criteria is desirable. This consistency is based on the treatment of alignment gaps as character information and the consistent use of a cost function (e.g., insertion-deletion, transversion, and transition) through analysis from alignment to phylogeny reconstruction. Cost functions are not subject to testing via inspection; hence the assumptions they make should be examined by varying the assumed values in a sensitivity analysis context to test for the robustness of results. Agreement among data may be used to choose an optimal solution set from all of those examined through parameter variation. This idea of consistency between assumption and analysis through alignment and cladogram reconstruction is not limited to parsimony analysis and could and should be applied to other forms of analysis such as maximum likelihood.

Purification and properties of Escherichia coli dihydrofolate reductase

Dihydrofolate reductase has been purified 40-fold to apparent homogeneity from a trimethoprim-resistant strain of Escherichia coli (RT 500) using a procedure that includes methotrexate affinity column chromatography. Determinations of the molecular weight of the enzyme based on its amino acid composition, sedimentation velocity, and sodium dodecyl sulfate gel electrophoresis gave values of 17680, 17470 and 18300, respectively. An aggregated form of the enzyme with a low specific activity can be separated from the monomer by gel filtration; treatment of the aggregate with mercaptoethanol or dithiothreitol results in an increase in enzymic activity and a regeneration of the monomer. Also, multiple molecular forms of the monomer have been detected by polyacrylamide gel electrophoresis. The unresolved enzyme exhibits two pH optima (pH 4.5 and pH 7.0) with dihydrofolate as a substrate. Highest activities are observed in buffers containing large organic cations. In 100 mM imidazolium chloride (pH 7), the specific activity is 47 mumol of dihydrofolate reduced per min per mg at 30 degrees. Folic acid also serves as a substrate with a single pH optimum of pH 4.5. At this pH the Km for folate is 16 muM, and the Vmax is 1/1000 of the rate observed with dihydrofolate as the substrate. Monovalent cations (Na+, K+, Rb+, and Cs+) inhibit dihydrofolate reductase; at a given ionic strength the degree of inhibition is a function of the ionic radius of the cation. Divalent cations are more potent inhibitors; the I50 of BaCl2 is 250 muM, as compared to 125 mM for KCl. Anions neither inhibit nor activate the enzyme.

A comparison of sclerotherapy with staple transection of the esophagus for the emergency control of bleeding from esophageal varices

We compared two procedures for the emergency treatment of bleeding esophageal varices in patients who did not respond to blood transfusion and vasoactive drugs. We randomly assigned 101 patients with cirrhosis of the liver and bleeding esophageal varices to undergo either emergency sclerotherapy (n = 50) or staple transection of the esophagus (n = 51). Four patients assigned to sclerotherapy and 12 assigned to staple transection did not actually undergo those procedures, but all analyses were made on an intention-to-treat basis. Total mortality did not differ significantly between the two groups; the relative risk of death for staple transection as compared with sclerotherapy was 0.88 (95 percent confidence interval, 0.51 to 1.54). Mortality at six weeks was 44 percent among those assigned to sclerotherapy and 35 percent among those assigned to staple transection. Complication rates were similar for the two groups. An interval of five days without bleeding was achieved in 88 percent of those assigned to staple transection and in 62 percent of those assigned to sclerotherapy after a single injection (P less than 0.01) and 82 percent after three injections. In only 2 of the 11 patients who received a third sclerotherapy injection was bleeding controlled for more than five days, and 9 died. We conclude that staple transection of the esophagus is as safe as sclerotherapy for the emergency treatment of bleeding esophageal varices and that it is more effective than a single sclerotherapy procedure. We currently recommend surgery after two injection treatments have failed.