B-cell depletion with rituximab in relapsing-remitting multiple sclerosis

BACKGROUND

There is increasing evidence that B lymphocytes are involved in the pathogenesis of multiple sclerosis, and they may be a therapeutic target. Rituximab, a monoclonal antibody, selectively targets and depletes CD20+ B lymphocytes.

METHODS

In a phase 2, double-blind, 48-week trial involving 104 patients with relapsing-remitting multiple sclerosis, we assigned 69 patients to receive 1000 mg of intravenous rituximab and 35 patients to receive placebo on days 1 and 15. The primary end point was the total count of gadolinium-enhancing lesions detected on magnetic resonance imaging scans of the brain at weeks 12, 16, 20, and 24. Clinical outcomes included safety, the proportion of patients who had relapses, and the annualized rate of relapse.

RESULTS

As compared with patients who received placebo, patients who received rituximab had reduced counts of total gadolinium-enhancing lesions at weeks 12, 16, 20, and 24 (P<0.001) and of total new gadolinium-enhancing lesions over the same period (P<0.001); these results were sustained for 48 weeks (P<0.001). As compared with patients in the placebo group, the proportion of patients in the rituximab group with relapses was significantly reduced at week 24 (14.5% vs. 34.3%, P=0.02) and week 48 (20.3% vs. 40.0%, P=0.04). More patients in the rituximab group than in the placebo group had adverse events within 24 hours after the first infusion, most of which were mild-to-moderate events; after the second infusion, the numbers of events were similar in the two groups.

CONCLUSIONS

A single course of rituximab reduced inflammatory brain lesions and clinical relapses for 48 weeks. This trial was not designed to assess long-term safety or to detect uncommon adverse events. The data provide evidence of B-cell involvement in the pathophysiology of relapsing-remitting multiple sclerosis. (ClinicalTrials.gov number, NCT00097188 [ClinicalTrials.gov].).

Positional cloning of the gene for multiple endocrine neoplasia-type 1

Multiple endocrine neoplasia-type 1 (MEN1) is an autosomal dominant familial cancer syndrome characterized by tumors in parathyroids, enteropancreatic endocrine tissues, and the anterior pituitary. DNA sequencing from a previously identified minimal interval on chromosome 11q13 identified several candidate genes, one of which contained 12 different frameshift, nonsense, missense, and in-frame deletion mutations in 14 probands from 15 families. The MEN1 gene contains 10 exons and encodes a ubiquitously expressed 2.8-kilobase transcript. The predicted 610-amino acid protein product, termed menin, exhibits no apparent similarities to any previously known proteins. The identification of MEN1 will enable improved understanding of the mechanism of endocrine tumorigenesis and should facilitate early diagnosis.

The efficacy and safety of rituximab in patients with active rheumatoid arthritis despite methotrexate treatment: results of a phase IIB randomized, double-blind, placebo-controlled, dose-ranging trial

OBJECTIVE

To examine the efficacy and safety of different rituximab doses plus methotrexate (MTX), with or without glucocorticoids, in patients with active rheumatoid arthritis (RA) resistant to disease-modifying antirheumatic drugs (DMARDs), including biologic agents.

METHODS

A total of 465 patients were randomized into 9 treatment groups: 3 rituximab groups (placebo [n = 149], 500 mg [n = 124], or 1,000 mg [n = 192] on days 1 and 15) each also taking either placebo glucocorticoids, intravenous methylprednisolone premedication, or intravenous methylprednisolone premedication plus oral prednisone for 2 weeks. All patients received MTX (10-25 mg/week); no other DMARDs were permitted.

RESULTS

Significantly more patients who received 2 500-mg or 2 1,000-mg infusions of rituximab met the American College of Rheumatology 20% improvement criteria (achieved an ACR20 response) at week 24 (55% and 54%, respectively) compared with placebo (28%; P < 0.0001). ACR50 responses were achieved by 33%, 34%, and 13% of patients, respectively (P < 0.001), and ACR70 responses were achieved by 13%, 20%, and 5% of patients (P < 0.05). Changes in the Disease Activity Score in 28 joints (-1.79, -2.05, -0.67; P < 0.0001) and moderate to good responses on the European League Against Rheumatism criteria (P < 0.0001) reflected the ACR criteria responses. Glucocorticoids did not contribute significantly to the primary efficacy end point, ACR20 response at 24 weeks. Intravenous glucocorticoid premedication reduced the frequency and intensity of first infusion-associated events; oral glucocorticoids conferred no additional safety benefit. Rituximab was well tolerated; the type and severity of infections was similar to those for placebo.

CONCLUSION

Both rituximab doses were effective and well tolerated when added to MTX therapy in patients with active RA. The primary end point (ACR20 response) was independent of glucocorticoids, although intravenous glucocorticoid premedication improved tolerability during the first rituximab infusion.

Omalizumab for the treatment of chronic idiopathic or spontaneous urticaria

BACKGROUND

Many patients with chronic idiopathic urticaria (also called chronic spontaneous urticaria) do not have a response to therapy with H-antihistamines, even at high doses. In phase 2 trials, omalizumab, an anti-IgE monoclonal antibody [corrected] that targets IgE and affects mast-cell and basophil function, has shown efficacy in such patients.

METHODS

In this phase 3, multicenter, randomized, double-blind study, we evaluated the efficacy and safety of omalizumab in patients with moderate-to-severe chronic idiopathic urticaria who remained symptomatic despite H-antihistamine therapy (licensed doses). We randomly assigned 323 patients to receive three subcutaneous injections, spaced 4 weeks apart, of omalizumab at doses of 75 mg, 150 mg, or 300 mg or placebo, followed by a 16-week observation period. The primary efficacy outcome was the change from baseline in a weekly itch-severity score (ranging from 0 to 21, with higher scores indicating more severe itching).

RESULTS

The baseline weekly itch-severity score was approximately 14 in all four study groups. At week 12, the mean (±SD) change from baseline in the weekly itch-severity score was -5.1±5.6 in the placebo group, -5.9±6.5 in the 75-mg group (P=0.46), -8.1±6.4 in the 150-mg group (P=0.001), and -9.8±6.0 in the 300-mg group (P<0.001). Most prespecified secondary outcomes at week 12 showed similar dose-dependent effects. The frequency of adverse events was similar across groups. The frequency of serious adverse events was low, although the rate was higher in the 300-mg group (6%) than in the placebo group (3%) or in either the 75-mg or 150-mg group (1% for each).

CONCLUSIONS

Omalizumab diminished clinical symptoms and signs of chronic idiopathic urticaria in patients who had remained symptomatic despite the use of approved doses of H-antihistamines. (Funded by Genentech and Novartis Pharma; ClinicalTrials.gov number, NCT01292473.).

Simple risk model predicts incidence of atrial fibrillation in a racially and geographically diverse population: the CHARGE-AF consortium

BACKGROUND

Tools for the prediction of atrial fibrillation (AF) may identify high-risk individuals more likely to benefit from preventive interventions and serve as a benchmark to test novel putative risk factors.

METHODS AND RESULTS

Individual-level data from 3 large cohorts in the United States (Atherosclerosis Risk in Communities [ARIC] study, the Cardiovascular Health Study [CHS], and the Framingham Heart Study [FHS]), including 18 556 men and women aged 46 to 94 years (19% African Americans, 81% whites) were pooled to derive predictive models for AF using clinical variables. Validation of the derived models was performed in 7672 participants from the Age, Gene and Environment-Reykjavik study (AGES) and the Rotterdam Study (RS). The analysis included 1186 incident AF cases in the derivation cohorts and 585 in the validation cohorts. A simple 5-year predictive model including the variables age, race, height, weight, systolic and diastolic blood pressure, current smoking, use of antihypertensive medication, diabetes, and history of myocardial infarction and heart failure had good discrimination (C-statistic, 0.765; 95% CI, 0.748 to 0.781). Addition of variables from the electrocardiogram did not improve the overall model discrimination (C-statistic, 0.767; 95% CI, 0.750 to 0.783; categorical net reclassification improvement, -0.0032; 95% CI, -0.0178 to 0.0113). In the validation cohorts, discrimination was acceptable (AGES C-statistic, 0.664; 95% CI, 0.632 to 0.697 and RS C-statistic, 0.705; 95% CI, 0.664 to 0.747) and calibration was adequate.

CONCLUSION

A risk model including variables readily available in primary care settings adequately predicted AF in diverse populations from the United States and Europe.

A comparative evaluation of thiobarbituric acid methods for the determination of malondialdehyde in biological materials

A comparative evaluation was made of the conventional spectrophotometric procedure and three published high performance liquid chromatographic (HPLC) procedures for the determination of malondialdehyde (MDA) as the thiobarbituric acid (TBA) derivative when applied to liver, fish meal, serum, and urine. Except for urine, spectrophotometric analysis overestimated MDA content. Purification of the TBA-MDA complex obtained from liver and fish meal on reverse phase cartridges was found to entail a loss of complex bound to residual peptides in the trichloracetic acid (TCA) extract. Mincing as opposed to homogenizing liver samples led to a doubling of values for MDA content. Hexanal was a major TBA reactant, in addition to MDA, in all the samples. Acid hydrolysis and heat were necessary for the release of MDA bound to the amino groups of proteins and other amino compounds. Methods for free MDA have limited application to biological materials except short term in vitro preparations such as peroxidizing microsomes, in which free MDA accumulates. On the basis of these and other observations, a modified HPLC procedure for the determination of MDA as the TBA-MDA complex is proposed.

Modulation of chromatin structure regulates cytokine gene expression during T cell differentiation

Differentiating cells undergo programmed alterations in their patterns of gene expression, which are often regulated by structural changes in chromatin. Here we demonstrate that T cell differentiation results in long-range changes in the chromatin structure of effector cytokine genes, which persist in resting Th1 and Th2 cells in the absence of further stimulation. Differentiation of naive T helper cells into mature Th2 cells is associated with chromatin remodeling of the IL-4 and IL-13 genes, whereas differentiation into Th1 cells evokes remodeling of the IFNgamma but not IL-4 or IL-13 genes. IL-4 locus remodeling is accompanied by demethylation and requires both antigen stimulation and STAT6 activation. We propose that chromatin remodeling of cytokine gene loci is functionally associated with productive T cell differentiation and may explain the coordinate regulation of Th2 cytokine genes.

Oxidative damage, mitochondrial oxidant generation and antioxidant defenses during aging and in response to food restriction in the mouse

This study was conducted in order to test the concept that oxidative damage is associated with aging and may be a factor in the modulation of life span in response to variations in caloric intake. Mice fed a diet that was 40% lower in calories (DR) than the ad libitum fed (AL) animals exhibited a 43% extension in average life span and a 61% prolongation in mortality rate doubling time. A comparison of AL and DR mice at 9, 17 and 23 months of age indicated that the protein carbonyl content in the brain, heart and kidney increased with age and was significantly greater in the AL than DR group in each organ at each of the three ages. Mitochondrial state 4 or resting respiratory rate increased with age in the AL, but not the DR group, and was also relatively higher in the former. The rates of mitochondrial superoxide and hydrogen peroxide generation increased with age and were higher in the AL than DR mice in all the three organs at each age. In contrast, there was no clear-cut overall pattern of age-related or dietary-related changes in antioxidant defenses provided by superoxide dismutase, catalase and glutathione peroxidase. Results suggest that mechanisms of aging and life span shortening by enhanced caloric intake are associated with oxidative damage arising from corresponding changes in mitochondrial oxidant production. Protein carbonyl content, and mitochondrial O2.- and H2O2 generation may act as indices of aging.

Absolute and attributable risks of atrial fibrillation in relation to optimal and borderline risk factors: the Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND

Atrial fibrillation (AF) is an important risk factor for stroke and overall mortality, but information about the preventable burden of AF is lacking. The aim of this study was to determine what proportion of the burden of AF in blacks and whites could theoretically be avoided by the maintenance of an optimal risk profile.

METHODS AND RESULTS

This study included 14 598 middle-aged Atherosclerosis Risk in Communities (ARIC) Study cohort members. Previously established AF risk factors, namely high blood pressure, elevated body mass index, diabetes mellitus, cigarette smoking, and prior cardiac disease, were categorized into optimal, borderline, and elevated levels. On the basis of their risk factor levels, individuals were classified into 1 of these 3 groups. The population-attributable fraction of AF resulting from having a nonoptimal risk profile was estimated separately for black and white men and women. During a mean follow-up of 17.1 years, 1520 cases of incident AF were identified. The age-adjusted incidence rates were highest in white men and lowest in black women (7.45 and 3.67 per 1000 person-years, respectively). The overall prevalence of an optimal risk profile was 5.4% but varied according to race and gender: 10% in white women versus 1.6% in black men. Overall, 56.5% of AF cases could be explained by having ≥ 1 borderline or elevated risk factors, of which elevated blood pressure was the most important contributor.

CONCLUSION

As with other forms of cardiovascular disease, more than half of the AF burden is potentially avoidable through the optimization of cardiovascular risk factors levels.

Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial

BACKGROUND

Roughly a third of patients with rheumatoid arthritis treated with biological treatments receive them as monotherapy. Tocilizumab--an inhibitor of interleukin 6 receptor signalling--has been studied as monotherapy in several clinical trials. We assessed the efficacy and safety of tocilizumab monotherapy compared with adalimumab monotherapy for patients with rheumatoid arthritis.

METHODS

We did this randomised, double-blind, parallel-group, phase 4 superiority study in 76 centres in 15 countries in North and South America, Australasia, and Europe. We enrolled patients who were aged at least 18 years, had severe rheumatoid arthritis for 6 months or more, and were intolerant to methotrexate or were inappropriate for continued methotrexate treatment. Patients were randomly assigned (1:1; block size of four) to receive tocilizumab 8 mg per kg bodyweight intravenously every 4 weeks plus placebo subcutaneously every 2 weeks or adalimumab 40 mg subcutaneously every 2 weeks plus placebo intravenously every 4 weeks for 24 weeks. Investigators, patients, and sponsor personnel were masked to assignment. The primary endpoint was change in disease activity score using 28 joints (DAS28) from baseline to week 24. This trial is registered with ClinicalTrials.gov, number NCT01119859.

FINDINGS

We screened 452 patients and enrolled 326 patients. The intention-to-treat population contained 325 patients (163 assigned to tocilizumab, 162 assigned to adalimumab). Week 24 mean change from baseline in DAS28 was significantly greater in the tocilizumab group (-3·3) than in the adalimumab group (-1·8) patients (difference -1·5, 95% CI -1·8 to -1·1; p<0·0001). 16 of 162 (10%) patients in the adalimumab group versus 19 of 162 (12%) in the tocilizumab group had serious adverse events. More patients in the tocilizumab group than in the adalimumab group had increased LDL-cholesterol, increased alanine aminotransferase concentrations, and reduced platelet and neutrophil counts.

INTERPRETATION

Tocilizumab monotherapy was superior to adalimumab monotherapy for reduction of signs and symptoms of rheumatoid arthritis in patients for whom methotrexate was deemed inappropriate. The adverse event profiles of tocilizumab and adalimumab were consistent with previous findings.

FUNDING

F Hoffmann-La Roche.

HRPT2, encoding parafibromin, is mutated in hyperparathyroidism-jaw tumor syndrome

We report here the identification of a gene associated with the hyperparathyroidism-jaw tumor (HPT-JT) syndrome. A single locus associated with HPT-JT (HRPT2) was previously mapped to chromosomal region 1q25-q32. We refined this region to a critical interval of 12 cM by genotyping in 26 affected kindreds. Using a positional candidate approach, we identified thirteen different heterozygous, germline, inactivating mutations in a single gene in fourteen families with HPT-JT. The proposed role of HRPT2 as a tumor suppressor was supported by mutation screening in 48 parathyroid adenomas with cystic features, which identified three somatic inactivating mutations, all located in exon 1. None of these mutations were detected in normal controls, and all were predicted to cause deficient or impaired protein function. HRPT2 is a ubiquitously expressed, evolutionarily conserved gene encoding a predicted protein of 531 amino acids, for which we propose the name parafibromin. Our findings suggest that HRPT2 is a tumor-suppressor gene, the inactivation of which is directly involved in predisposition to HPT-JT and in development of some sporadic parathyroid tumors.

Rituximab in relapsing-remitting multiple sclerosis: a 72-week, open-label, phase I trial

We evaluated the safety, tolerability, pharmacodynamics, and activity of B-cell depletion with rituximab in patients with relapsing-remitting multiple sclerosis, receiving two courses of rituximab 6 months apart, and followed for a total of 72 weeks. No serious adverse events were noted; events were limited to mild-to-moderate infusion-associated events, which tended to decrease with subsequent infusions. Infections were also mild or moderate, and none led to withdrawal. Fewer new gadolinium-enhancing or T2 lesions were seen starting from week 4 and through week 72. An apparent reduction in relapses was also observed over the 72 weeks compared with the year before therapy.

Chronic kidney disease is associated with the incidence of atrial fibrillation: the Atherosclerosis Risk in Communities (ARIC) study

BACKGROUND

Chronic kidney disease is associated with the incidence of cardiovascular disease. Chronic kidney disease may also increase the risk of atrial fibrillation (AF), but existing studies have reported inconsistent results.

METHODS AND RESULTS

We estimated cystatin C-based glomerular filtration rate (eGFR(cys)) and measured urinary albumin-to-creatinine ratio (ACR) in 10 328 men and women free of AF from the Atherosclerosis Risk in Communities (ARIC) Study in 1996 to 1998. Incidence of AF was ascertained through the end of 2007. During a median follow-up of 10.1 years, we identified 788 incident AF cases. Compared with individuals with eGFR(cys) ≥90 mL · min(-1) · 1.73 m(-2), multivariable hazard ratios and 95% confidence intervals (CIs) of AF were 1.3 (95% CI, 1.1 to 1.6), 1.6 (95% CI, 1.3 to 2.1), and 3.2 (95% CI, 2.0 to 5.0; P for trend <0.0001) in those with eGFR(cys) of 60 to 89, 30 to 59, and 15 to 29 mL · min(-1) · 1.73 m(-2), respectively. Similarly, the presence of macroalbuminuria (ACR ≥300 mg/g; hazard ratio, 3.2; 95% CI, 2.3 to 4.5) and microalbuminuria (ACR, 30 to 299 mg/g; hazard ratio, 2.0; 95% CI, 1.6 to 2.4) was associated with higher AF risk compared with those with ACR <30 mg/g. Risk of AF was particularly elevated in those with both low eGFR(cys) and macroalbuminuria (hazard ratio, 13.1; 95% CI, 6.0 to 28.6, comparing individuals with ACR ≥300 mg/g and eGFR(cys) of 15 to 29 mL · min(-1) · 1.73 m(-2) and those with ACR <30 mg/g and eGFR(cys) ≥90 mL · min(-1) · 1.73 m(-2)).

CONCLUSION

In this large population-based study, reduced kidney function and presence of albuminuria were strongly associated with the incidence of AF independently of other risk factors.

Large-scale analysis of the yeast genome by transposon tagging and gene disruption

Economical methods by which gene function may be analysed on a genomic scale are relatively scarce. To fill this need, we have developed a transposon-tagging strategy for the genome-wide analysis of disruption phenotypes, gene expression and protein localization, and have applied this method to the large-scale analysis of gene function in the budding yeast Saccharomyces cerevisiae. Here we present the largest collection of defined yeast mutants ever generated within a single genetic background--a collection of over 11,000 strains, each carrying a transposon inserted within a region of the genome expressed during vegetative growth and/or sporulation. These insertions affect nearly 2,000 annotated genes, representing about one-third of the 6,200 predicted genes in the yeast genome. We have used this collection to determine disruption phenotypes for nearly 8,000 strains using 20 different growth conditions; the resulting data sets were clustered to identify groups of functionally related genes. We have also identified over 300 previously non-annotated open reading frames and analysed by indirect immunofluorescence over 1,300 transposon-tagged proteins. In total, our study encompasses over 260,000 data points, constituting the largest functional analysis of the yeast genome ever undertaken.

Menin interacts with the AP1 transcription factor JunD and represses JunD-activated transcription

MEN1 is a tumor suppressor gene that encodes a 610 amino acid nuclear protein (menin) of previously unknown function. Using a yeast two-hybrid screen with menin as the bait, we have identified the transcription factor JunD as a direct menin-interacting partner. Menin did not interact directly with other Jun and Fos family members. The menin-JunD interaction was confirmed in vitro and in vivo. Menin repressed transcriptional activation mediated by JunD fused to the Gal4 DNA-binding domain from a Gal4 responsive reporter, or by JunD from an AP1-responsive reporter. Several naturally occurring and clustered MEN1 missense mutations disrupted menin interaction with JunD. These observations suggest that menin's tumor suppressor function involves direct binding to JunD and inhibition of JunD activated transcription.

Exercise training in patients with heart failure and preserved ejection fraction: meta-analysis of randomized control trials

BACKGROUND

Heart failure with preserved ejection fraction (HFPEF) is common and characterized by exercise intolerance and lack of proven effective therapies. Exercise training has been shown to be effective in improving cardiorespiratory fitness (CRF) in patients with systolic heart failure. In this meta-analysis, we aim to evaluate the effects of exercise training on CRF, quality of life, and diastolic function in patients with HFPEF.

METHODS AND RESULTS

Randomized controlled clinical trials that evaluated the efficacy of exercise training in patients with HFPEF were included in this meta-analysis. Primary outcome of the study was change in CRF (measured as change in peak oxygen uptake). Effect of exercise training on quality of life (estimated using Minnesota living with heart failure score), and left ventricular systolic and diastolic function was also assessed. The study included 276 patients who were enrolled in 6 randomized controlled trials. In the pooled data analysis, patients with HFPEF undergoing exercise training had significantly improved CRF (mL/kg per min; weighted mean difference, 2.72; 95% confidence interval, 1.79-3.65) and quality of life (weighted mean difference, -3.97; 95% confidence interval, -7.21 to -0.72) when compared with the control group. However, no significant change was observed in the systolic function (EF-weighted mean difference, 1.26; 95% confidence interval, -0.13% to 2.66%) or diastolic function (E/A-weighted mean difference, 0.08; 95% confidence interval, -0.01 to 0.16) with exercise training in patients with HFPEF.

CONCLUSIONS

Exercise training in patients with HFPEF is associated with an improvement in CRF and quality of life without significant changes in left ventricular systolic or diastolic function.

Adenovirus enhancement of transferrin-polylysine-mediated gene delivery

Gene transfer may be accomplished by the receptor-mediated endocytosis pathway using transferrin-polylysine conjugates. For some target cells, however, gene transfer by this vector is extremely limited, despite the presence of the appropriate surface receptors, a phenomenon attributed to lysosomal degradation of endosome-internalized conjugate-DNA complexes. To enhance DNA escape from the cell vesicle system and thus augment gene transfer by this route, we have used the capacity of adenoviruses to disrupt endosomes as part of their entry mechanism. Adenoviral infection augmented levels of gene transfer by transferrin-polylysine conjugates in a dose-dependent manner: levels of gene transfer of greater than 2000-fold above baseline were achieved. Use of the adenovirus in this context allowed enhanced levels of gene transfer in a variety of target cells, including cell lines otherwise refractory to gene transfer by transferrin-polylysine conjugates. This augmentation was based on adenoviral-mediated vesicle disruption, a process independent of viral gene expression. Thus, the development of specific mechanisms to effect release from the endosome in combination with gene transfer by the receptor-mediated endocytosis pathway will increase the utility of this delivery system by allowing high levels of gene expression in target cells.

Immunization responses in rheumatoid arthritis patients treated with rituximab: results from a controlled clinical trial

OBJECTIVE

To examine immunization responses in patients with rheumatoid arthritis (RA) treated with rituximab and to investigate the effects of rituximab-induced CD20+ B cell depletion on immune responses to tetanus toxoid (T cell-dependent antigen), pneumococcal polysaccharide (T cell-independent antigen), and keyhole limpet hemocyanin (KLH) (neoantigen) and on delayed-type hypersensitivity (DTH).

METHODS

In a controlled trial, we enrolled 103 patients with active RA receiving a stable dose of methotrexate (MTX). Tetanus toxoid, pneumococcal polysaccharide, and KLH vaccines as well as a Candida albicans skin test were administered to 1 group of patients receiving rituximab plus MTX (called rituximab-treated patients) for 36 weeks and to 1 group of patients receiving MTX alone for 12 weeks. The primary end point was the proportion of patients with a >or=4-fold rise in antitetanus IgG levels. Antitetanus, antipneumococcal, and anti-KLH serum IgG levels were measured prior to and 4 weeks following vaccine administration. The DTH response to C albicans was measured 2-3 days following placement.

RESULTS

Responses to tetanus toxoid vaccine (>or=4-fold rise) were similar in both groups (39.1% of rituximab-treated patients and 42.3% of patients treated with MTX alone). The ability to maintain a positive DTH response to the C albicans skin test was comparable in both groups (77.4% of rituximab-treated patients and 70% of patients treated with MTX alone), showing no effect of rituximab treatment. Rituximab-treated patients had decreased responses to pneumococcal polysaccharide vaccine (57% of patients had a 2-fold rise in titer in response to >or=1 serotype, compared with 82% of patients treated with MTX alone) and to KLH vaccine (47% of patients had detectable anti-KLH IgG, compared with 93% of patients treated with MTX alone).

CONCLUSION

Recall responses to the T cell-dependent protein antigen tetanus toxoid as well as DTH responses were preserved in rituximab-treated RA patients 24 weeks after treatment. Responses to neoantigen (KLH) and T cell-independent responses to pneumococcal vaccine were decreased, but many patients were able to mount responses. These data suggest that polysaccharide and primary immunizations should be administered prior to rituximab infusions to maximize responses.

Germline mutations of the MEN1 gene in familial multiple endocrine neoplasia type 1 and related states

Familial multiple endocrine neoplasia type 1 (FMEN1) is an autosomal dominant trait characterized by tumors of the parathyroids, gastro-intestinal endocrine tissue, anterior pituitary and other tissues. We recently cloned the MEN1 gene and confirmed its identity by finding mutations in FMEN1. We have now extended our mutation analysis to 34 more unrelated FMEN1 probands and to two related states, sporadic MEN1 and familial hyperparathyroidism. There was a high prevalence of heterozygous germline MEN1 mutations in sporadic MEN1 (8/11 cases) and in FMEN1 (47/50 probands). One case of sporadic MEN1 was proven to be a new MEN1 mutation. Eight different mutations were observed more than once in FMEN1. Forty different mutations (32 FMEN1 and eight sporadic MEN1) were distributed across the MEN1 gene. Most predicted loss of function of the encoded menin protein, supporting the prediction that MEN1 is a tumor suppressor gene. No MEN1 germline mutation was found in five probands with familial hyperparathyroidism, suggesting that familial hyperparathyroidism often is caused by mutation in another gene or gene(s).

Tomato lycopene and low density lipoprotein oxidation: a human dietary intervention study

Increase in low density lipoprotein (LDL) oxidation is hypothesized to be causally associated with increasing risk of atherosclerosis and coronary heart disease. In recent epidemiological studies, tissue and serum levels of lycopene, a carotenoid available from tomatoes, have been found to be inversely related to risk of coronary heart disease. A study was undertaken to investigate the effect of dietary supplementation of lycopene on LDL oxidation in 19 healthy human subjects. Dietary lycopene was provided using tomato juice, spaghetti sauce, and tomato oleoresin for a period of 1 wk each. Blood samples were collected at the end of each treatment. Serum lycopene was extracted and measured by high-performance liquid chromatography using an absorbance detector. Serum LDL was isolated by precipitation with buffered heparin, and thiobarbituric acid-reactive substances (TBARS) and conjugated dienes (CD) were measured to estimate LDL oxidation. Both methods, to measure LDL oxidation LDL-TBARS and LDL-CD, were in good agreement with each other. Dietary supplementation of lycopene significantly increased serum lycopene levels by at least twofold. Although there was no change in serum cholesterol levels (total, LDL, or high-density lipoprotein), serum lipid peroxidation and LDL oxidation were significantly decreased. These results may have relevance for decreasing the risk for coronary heart disease.

Variants in ZFHX3 are associated with atrial fibrillation in individuals of European ancestry

We conducted meta-analyses of genome-wide association studies (GWAS) for atrial fibrillation (AF) in participants from five community-based cohorts. Meta-analyses of 896 prevalent (15,768 referents) and 2,517 incident (21,337 referents) AF cases identified a novel locus for AF (ZFHX3, rs2106261, risk ratio [RR]=1.19; P=2.3×10⁻⁷), an association that was replicated in the German AF Network (odds ratio=1.44; P=1.6×10⁻¹¹). Combining the discovery and replication results, rs2106261 was significantly associated with AF (RR=1.25; P=1.8×10⁻¹⁵).

The problem of appraising qualitative research

Qualitative research can make a valuable contribution to the study of quality and safety in health care. Sound ways of appraising qualitative research are needed, but currently there are many different proposals with few signs of an emerging consensus. One problem has been the tendency to treat qualitative research as a unified field. We distinguish universal features of quality from those specific to methodology and offer a set of minimally prescriptive prompts to assist with the assessment of generic features of qualitative research. In using these, account will need to be taken of the particular method of data collection and methodological approach being used. There may be a need for appraisal criteria suited to the different methods of qualitative data collection and to different methodological approaches. These more specific criteria would help to distinguish fatal flaws from more minor errors in the design, conduct, and reporting of qualitative research. There will be difficulties in doing this because some aspects of qualitative research, particularly those relating to quality of insight and interpretation, will remain difficult to appraise and will rely largely on subjective judgement.

Somatic mutation of the MEN1 gene in parathyroid tumours

Primary hyperparathyroidism is a common disorder with an annual incidence of approximately 0.5 in 1,000 (ref. 1). In more than 95% of cases, the disease is caused by sporadic parathyroid adenoma or sporadic hyperplasia. Some cases are caused by inherited syndromes, such as multiple endocrine neoplasia type 1 (MEN1; ref. 2). In most cases, the molecular basis of parathyroid neoplasia is unknown. Parathyroid adenomas are usually monoclonal, suggesting that one important step in tumour development is a mutation in a progenitor cell. Approximately 30% of sporadic parathyroid tumours show loss of heterozygosity (LOH) for polymorphic markers on 11q13, the site of the MEN1 tumour suppressor gene. This raises the question of whether such sporadic parathyroid tumours are caused by sequential inactivation of both alleles of the MEN1 gene. We recently cloned the MEN1 gene and identified MEN1 germline mutations in fourteen of fifteen kindreds with familial MEN1 (ref. 10). We have studied parathyroid tumours not associated with MEN1 to determine whether somatic mutations in the MEN1 gene are present. Among 33 tumours we found somatic MEN1 gene mutation in 7, while the corresponding MEN1 germline sequence was normal in each patient. All tumours with MEN1 gene mutation showed LOH on 11q13, making the tumour cells hemi- or homozygous for the mutant allele. Thus, somatic MEN1 gene mutation for the mutant allele. Thus, somatic MEN1 gene mutation contributes to tumorigenesis in a substantial number of parathyroid tumours not associated with the MEN1 syndrome.

Role of antioxidant lycopene in cancer and heart disease

Lycopene, a carotenoid without provitamin-A activity, is present in many fruits and vegetables; however, tomatoes and processed tomato products constitute the major source of lycopene in North American diet. Among the carotenoids, lycopene is a major component found in the serum and other tissues. Dietary intakes of tomatoes and tomato products containing lycopene have been shown to be associated with decreased risk of chronic diseases such as cancer and cardiovascular diseases in several recent studies. Serum and tissue lycopene levels have also been inversely related with the chronic disease risk. Although the antioxidant properties of lycopene are thought to be primarily responsible for its beneficial properties, evidence is accumulating to suggest other mechanisms such as modulation of intercellular gap junction communication, hormonal and immune system and metabolic pathways may also be involved. This review summarizes the background information about lycopene and presents the most current knowledge with respect to its role in human health and disease.

Effect of age and caloric restriction on DNA oxidative damage in different tissues of C57BL/6 mice

The objective of this study was to explore the role of molecular oxidative damage and caloric intake in the aging process. The concentration of 8-hydroxydeoxyguanosine (8-OHdG), a product of DNA oxidation, was compared in five different tissues of mice (skeletal muscle, brain, heart, liver and kidney) as a function of age and in response to dietary restriction. A comparison of 8- and 27-month-old mice indicated that the age-related increase in 8-OHdG concentration was greater in skeletal muscle, brain and heart, which are primarily composed of long-lived, post-mitotic cells, than in liver and kidney, which consist of slow-dividing cells. Dietary restricted (DR) mice kept on 60% caloric intake as compared to the ad libitum-fed (AL) mice showed a lower concentration in 8-OHdG content in all the tissues compared to AL mice. The DR-related amelioration of DNA oxidative damage was greater in the post-mitotic tissues compared to those undergoing slow mitoses. Results support the hypothesis that oxidative damage to long-lived post-mitotic cells may be a key factor in the aging process.