Arrhythmogenic cardiomyopathy: etiology, diagnosis, and treatment

Arrhythmogenic right ventricular cardiomyopathy (ARVC) has a prevalence of at least 1 in 1000, is a leading cause of sudden cardiac death in people aged < or =35 years, and accounts for up to 10% of deaths from undiagnosed cardiac disease in the <65 age group. The classic form of the disease has an early predilection for the right ventricle, but recognition of left-dominant and biventricular subtypes has prompted proposal of the broader term arrhythmogenic cardiomyopathy. The clinical profile of the disease bridges the gap between the cardiomyopathies and inherited arrhythmia syndromes. The early "concealed" phase is characterized by propensity toward ventricular tachyarrhythmia in the setting of well-preserved morphology, histology, and ventricular function. As the disease progresses, however, myocyte loss, inflammation, and fibroadiposis become evident. Up to 40% of cases harbor rare variants in genes encoding components of the desmosome, specialized intercellular junctions that confer mechanical strength to cardiac and epithelial tissue, and may also participate in signaling networks. Phenotypic heterogeneity and the nonspecific nature of associated features complicate clinical diagnosis, which requires multipronged cardiovascular investigation rather than a single test. Development of a prospectively validated risk-stratification algorithm for the full disease spectrum remains the foremost clinical challenge.

Therapeutic angiogenesis for cardiovascular disease: biological context, challenges, prospects

Since the discovery of vascular endothelial growth factor (VEGF), therapeutic angiogenesis has attracted interest as an alternative treatment for ischaemic heart and peripheral disease. In parallel, the view has also gained ground that angiogenesis has an important role in the pathogenesis of atherosclerotic disease and its clinical sequelae. These conflicting perspectives have both been based on a large quantity of preclinical data obtained from mainly small rodent models of disease. However, in recent years further research and the results of clinical trials of pro-angiogenic and anti-angiogenic treatments have provided new insights into the impact of VEGF and other angiogenesis-based approaches on human health and disease. This review discusses therapeutic angiogenesis in the light of recent scientific advances and clinical evidence, and considers the future challenges and prospects for therapeutic angiogenesis.

Systematic review and meta-analysis of hypothermic machine perfusion versus static cold storage of kidney allografts on transplant outcomes

BACKGROUND

Adequate preservation of renal allografts for transplantation is important for maintaining and improving transplant outcomes. There are two prevalent methods: hypothermic machine perfusion and static cold storage. The preferred method of storage, however, remains controversial. The objective was to review systematically the evidence comparing outcomes from these two modalities.

METHODS

A literature search was performed using MEDLINE, Embase, the Cochrane Library, the Transplant Library and the International Clinical Trials Registry Platform. The final date for searches was 30 November 2012. Studies were assessed for methodological quality. Summary effects were calculated as relative risk (RR) with 95 per cent confidence interval (c.i.). Randomized clinical trials (RCTs) and non-RCTs were included, but evaluated separately. Results from RCTs alone were used for meta-analysis.

RESULTS

Eighteen studies met the inclusion criteria, including seven RCTs (1475 kidneys) and 11 non-RCTs (728 kidneys). The overall risk of delayed graft function was lower with hypothermic machine perfusion than static cold storage (RR 0·81, 95 per cent c.i. 0·71 to 0·92; P = 0·002). There was no difference in the rate of primary non-function (RR 1·15, 0·46 to 2·90; P = 0·767). There was a faster initial fall in the level of serum creatinine with hypothermic machine perfusion in two RCTs, but not in another. There was no relationship between rates of acute rejection or patient survival and the method of preservation.

CONCLUSION

Data from the included studies suggest that hypothermic machine perfusion reduces delayed graft function compared with static cold storage. There was no difference in primary non-function, acute rejection, long-term renal function or patient survival. A difference in renal graft survival is uncertain.

DNA Replication Vulnerabilities Render Ovarian Cancer Cells Sensitive to Poly(ADP-Ribose) Glycohydrolase Inhibitors

Inhibitors of poly(ADP-ribose) polymerase (PARP) have demonstrated efficacy in women with BRCA-mutant ovarian cancer. However, only 15%-20% of ovarian cancers harbor BRCA mutations, therefore additional therapies are required. Here, we show that a subset of ovarian cancer cell lines and ex vivo models derived from patient biopsies are sensitive to a poly(ADP-ribose) glycohydrolase (PARG) inhibitor. Sensitivity is due to underlying DNA replication vulnerabilities that cause persistent fork stalling and replication catastrophe. PARG inhibition is synthetic lethal with inhibition of DNA replication factors, allowing additional models to be sensitized by CHK1 inhibitors. Because PARG and PARP inhibitor sensitivity are mutually exclusive, our observations demonstrate that PARG inhibitors have therapeutic potential to complement PARP inhibitor strategies in the treatment of ovarian cancer.

Identification of type II restriction and modification systems in Helicobacter pylori reveals their substantial diversity among strains

A total of 22 type II restriction endonucleases with 18 distinct specificities have been identified in six Helicobacter pylori strains. Among these 18 specificities are three completely new endonucleases, Hpy178III, Hpy99I, and Hpy188I, that specifically cleave DNA at TCNNGA, CGWCG, and TCNGA sites, respectively. The set of endonucleases identified in each strain varies, but all have four- or five-base recognition sequences. Among 16 H. pylori strains, examination of the DNA modification status at the recognition sites of 15 restriction endonucleases reveals that each strain has a substantially different complement of type II modification systems. We conclude that the type II restriction-modification systems in H. pylori are highly diverse between strains, a unique characteristic of H. pylori. The diverse methylation status of H. pylori chromosomal DNA may serve as a new typing system to discriminate H. pylori isolates for epidemiological and clinical purposes. This study also demonstrates that H. pylori is a rich source of type II restriction endonucleases.

Preservation solutions for static cold storage of kidney allografts: a systematic review and meta-analysis

Static cold storage is the most prevalent method for renal allograft preservation. Several solutions have been designed to counteract the detrimental effects of cold ischemia and reperfusion. The aim of this study was to appraise the evidence for the currently available preservation solutions. We performed a systematic literature search using MEDLINE, EMBASE, the Cochrane Library, the Transplant Library and trial registries. Inclusion criteria specified any comparative, prospective study for deceased donor renal allografts. Studies were assessed for methodological quality. The primary outcome was delayed graft function (DGF). Fifteen trials with a total of 3584 kidneys were included. Eurocollins was associated with a higher risk of DGF than University of Wisconsin solution (UW) in two randomized controlled trials (RCTs) and histidine-tryptophan-ketoglutarate (HTK) in two RCTs. UW was associated with an equal risk of DGF compared with Celsior in three RCTs and HTK in two RCTs. There was limited data regarding other comparisons and outcomes. The choice of preservation solution has an effect on the incidence of DGF, which might, in turn, affect long-term outcomes. Both UW and HTK have lower rates of DGF than Eurocollins. There is no difference in the incidence of DGF with the use of Celsior, HTK and UW. These findings are supported by registry data.

Discovery and distribution of super-integrons among pseudomonads

Until recently, integrons (systems for acquisition and expression of new genetic materials) have been associated generally with antibiotic resistance gene cassettes. The discovery of 'super-integrons' in Vibrionaceae suggests a greater impact of this gene acquisition mechanism on bacterial genome evolution than initially believed. Super-integrons may contain more than 100 gene cassettes and may encode other determinants, including biochemical functions or virulence factors. Here, we report the genetic organization of a super-integron from Pseudomonas alcaligenes ATCC 55044. This is the first evidence of a super-integron in a non-pathogenic bacterium, one which is widely distributed in a great number of ecological niches such as soil and aquatic habitats. Here, the sequence composition, open reading frame (ORF) content and organization of In55044 are described and found to have features intermediate between the multidrug-resistant integrons and the Vibrio cholerae super-integron. Similar structures are inferred to be present in several Pseudomonas species, based on polymerase chain reaction (PCR) experiments.

Distinct transcriptional programs stratify ovarian cancer cell lines into the five major histological subtypes

BACKGROUND

Epithelial ovarian cancer (OC) is a heterogenous disease consisting of five major histologically distinct subtypes: high-grade serous (HGSOC), low-grade serous (LGSOC), endometrioid (ENOC), clear cell (CCOC) and mucinous (MOC). Although HGSOC is the most prevalent subtype, representing 70-80% of cases, a 2013 landmark study by Domcke et al. found that the most frequently used OC cell lines are not molecularly representative of this subtype. This raises the question, if not HGSOC, from which subtype do these cell lines derive? Indeed, non-HGSOC subtypes often respond poorly to chemotherapy; therefore, representative models are imperative for developing new targeted therapeutics.

METHODS

Non-negative matrix factorisation (NMF) was applied to transcriptomic data from 44 OC cell lines in the Cancer Cell Line Encyclopedia, assessing the quality of clustering into 2-10 groups. Epithelial OC subtypes were assigned to cell lines optimally clustered into five transcriptionally distinct classes, confirmed by integration with subtype-specific mutations. A transcriptional subtype classifier was then developed by trialling three machine learning algorithms using subtype-specific metagenes defined by NMF. The ability of classifiers to predict subtype was tested using RNA sequencing of a living biobank of patient-derived OC models.

RESULTS

Application of NMF optimally clustered the 44 cell lines into five transcriptionally distinct groups. Close inspection of orthogonal datasets revealed this five-cluster delineation corresponds to the five major OC subtypes. This NMF-based classification validates the Domcke et al. analysis, in identifying lines most representative of HGSOC, and additionally identifies models representing the four other subtypes. However, NMF of the cell lines into two clusters did not align with the dualistic model of OC and suggests this classification is an oversimplification. Subtype designation of patient-derived models by a random forest transcriptional classifier aligned with prior diagnosis in 76% of unambiguous cases. In cases where there was disagreement, this often indicated potential alternative diagnosis, supported by a review of histological, molecular and clinical features.

CONCLUSIONS

This robust classification informs the selection of the most appropriate models for all five histotypes. Following further refinement on larger training cohorts, the transcriptional classification may represent a useful tool to support the classification of new model systems of OC subtypes.

Characterization of the specific DNA nicking activity of restriction endonuclease N.BstNBI

N.BstNBI is a unique restriction endonuclease isolated from Bacillus stearothermophilus. We have characterized the recognition sequence and the cleavage site of N.BstNBI. Mapping of cleavage sites of N.BstNBI showed that it recognizes an asymmetric sequence, 5' GAGTC 3', and cleaves only on the top strand 4 base pairs away from its recognition sequence. To verify the nicking activity of N. BstNBI, we have constructed two plasmids containing a single recognition sequence (pNB1) or no recognition site (pNB0). When pNB1 and pNB0 were incubated with the enzyme, N.BstNBI nicked only the plasmid pNB1, suggesting that N.BstNBI is a specific nicking endonuclease.

A living biobank of ovarian cancer ex vivo models reveals profound mitotic heterogeneity

High-grade serous ovarian carcinoma is characterised by TP53 mutation and extensive chromosome instability (CIN). Because our understanding of CIN mechanisms is based largely on analysing established cell lines, we developed a workflow for generating ex vivo cultures from patient biopsies to provide models that support interrogation of CIN mechanisms in cells not extensively cultured in vitro. Here, we describe a "living biobank" of ovarian cancer models with extensive replicative capacity, derived from both ascites and solid biopsies. Fifteen models are characterised by p53 profiling, exome sequencing and transcriptomics, and karyotyped using single-cell whole-genome sequencing. Time-lapse microscopy reveals catastrophic and highly heterogeneous mitoses, suggesting that analysis of established cell lines probably underestimates mitotic dysfunction in advanced human cancers. Drug profiling reveals cisplatin sensitivities consistent with patient responses, demonstrating that this workflow has potential to generate personalized avatars with advantages over current pre-clinical models and the potential to guide clinical decision making.

Thinking styles and emotional states of male and female prison inmates by mental disorder status

OBJECTIVES

This study explored criminal thinking styles and feelings of aggression and hopelessness among male and female inmates who reported mental disorders and those who did not.

METHODS

A total of 4,204 respondents (3,986 males and 218 females) who were expected to be released from prison within 24 months completed an hour-long audio computer-assisted self-interview survey that included the Beck Hopelessness Scale, Buss-Perry Aggression Questionnaire Short-Form, and Criminal Sentiments Scale-Modified. Weights were constructed to adjust the sampled population to the full population of the prison.

RESULTS

A mental disorder was reported by 19.8% of male and 46.1% of female participants, with 6.6% of males and 19.4% of females reporting a serious mental disorder. The criminal thinking patterns of male and female inmates who reported mental disorders were consistent with those of inmates who reported no mental disorders; however, levels of criminal attitudes were significantly higher among males reporting serious mental disorders than males reporting other mental disorders or no disorders. Inmates reporting mental disorders scored significantly higher on measures of aggression and hopelessness.

CONCLUSIONS

Results of this study suggest that inmates who report mental disorders have antisocial attitudes consistent with inmates who do not report mental disorders but have levels of aggression and hopelessness that are higher than their counterparts who do not report mental disorders. These findings are vital to the development of evidence-based interventions that respond accurately and holistically to the complex constellation of needs among persons with mental disorders who are involved in the justice system.

Does the use of telemental health alter the treatment experience? Inmates' perceptions of telemental health versus face-to-face treatment modalities

In corrections, where staffing limitations tax an overburdened mental health system, telemental health is an increasingly common mode of mental health service delivery. Although telemental health presents an efficient treatment modality for a spectrum of mental health services, it is imperative to study how this modality influences key elements of the treatment experience. In this study, the authors compared inmates' perceptions of the working alliance, postsession mood, and satisfaction with psychiatric and psychological mental health services delivered through 2 different modalities: telemental health and face-to-face. Participants consisted of 186 inmates who received mental health services (36 via telepsychology, 50 via face-to-face psychology, 50 via telepsychiatry, and 50 via face-to-face psychiatry). Results indicate no significant differences in inmates' perceptions of the work alliance with the mental health professional, postsession mood, or overall satisfaction with services when telemental health and face-to-face modalities were compared within each type of mental health service. Implications of these findings are presented.

Envisioning the next generation of behavioral health and criminal justice interventions

The purpose of this paper is to cast a vision for the next generation of behavioral health and criminal justice interventions for persons with serious mental illnesses in the criminal justice system. The limitations of first generation interventions, including their primary focus on mental health treatment connection, are discussed. A person-place framework for understanding the complex factors that contribute to criminal justice involvement for this population is presented. We discuss practice and research recommendations for building more effective interventions to address both criminal justice and mental health outcomes.

PARP inhibitors in platinum-sensitive high-grade serous ovarian cancer

Purpose

Poly(ADP-ribose) polymerase inhibitors (PARPi) have changed the management of high-grade serous ovarian cancer (HGSOC). The rationale for the development of PARPi was based on the concept of synthetic lethality, in which a cell can survive a deficiency of one gene/gene product, but may die if there is a deficiency in a combination of genes/gene products. In women with BRCA1/2 deficiency within their ovarian cancer tissue, inhibition of PARP imposes an intolerable burden of DNA damage repair deficiency and may induce cell death.

Methods

Clinical trials have evaluated PARPi as single-agent therapeutics and as maintenance treatment following platinum-based chemotherapy for HGSOC. Clinical data suggest the most impressive anti-tumour activity occurs in women with platinum-sensitive ovarian cancer and germline or somatic BRCA1/2 mutations (g/sBRCAmt).

Results

In the maintenance setting, randomised trials have shown that PARPi compared to placebo reduce the hazard ratio for the development of progressive disease to 0.2–0.27 for patients with a g/sBRCAmt; to 0.34–0.38 for patients with putative evidence of DNA damage repair deficiency; and to 0.35–0.45 in an unselected population with HGSOC. Furthermore, phase 1/2 trials have reported single-agent anti-tumour response rates in gBRCAmt of approximately 50% in platinum-sensitive and 25% in platinum-resistant disease.

Conclusion

Here, we discuss the evidence for the use of PARPi as single-agent therapeutics and maintenance treatment in HGSOC and evaluate the genetic assays used in clinical trials so far. We discuss the emerging role of platinum sensitivity as a broad eligibility criteria for the use of PARPi.

Treating offenders with mental illness: a research synthesis

The purpose of this research synthesis was to examine treatment effects across studies of the service providers to offenders with mental illness. Meta-analytic techniques were applied to 26 empirical studies obtained from a review of 12,154 research documents. Outcomes of interest in this review included measures of both psychiatric and criminal functioning. Although meta-analytic results are based on a small sample of available studies, results suggest interventions with offenders with mental illness effectively reduced symptoms of distress, improving offender's ability to cope with their problems, and resulted in improved behavioral markers including institutional adjustment and behavioral functioning. Furthermore, interventions specifically designed to meet the psychiatric and criminal justice needs of offenders with mental illness have shown to produce significant reductions in psychiatric and criminal recidivism. Finally, this review highlighted admission policies and treatment strategies (e.g., use of homework), which produced the most positive benefits. Results of this research synthesis are directly relevant for service providers in both criminal justice and mental health systems (e.g., psychiatric hospitals) as well as community settings by informing treatment strategies for the first time, which are based on empirical evidence. In addition, the implications of these results to policy makers tasked with the responsibility of designating services for this special needs population are highlighted.

A unique restriction endonuclease, BcgI, from Bacillus coagulans

We have purified and characterized a new restriction endonuclease, BcgI, which has properties unlike those of the three recognized classes of restriction enzymes. BcgI was isolated from Bacillus coagulans, and it recognizes the sequence CGAN6TGC. BcgI cleaves double stranded DNA on both strands upstream and downstream of the recognition sequence, so that the recognition sequence is released as a 34-base pair fragment with 2-base 3'-extensions. Mg++ and S-adenosylmethionine are required for cleavage. Sinefungin, a structural analogue of AdoMet which generally inhibits methylase activity, can replace AdoMet in the cleavage reaction. The apparent binding constant (Kappd) for AdoMet is about 100 nM, while the KappD for sinefungin is about 500 nM.

Prevalence of criminal thinking among state prison inmates with serious mental illness

To examine the prevalence of criminal thinking in mentally disordered offenders, incarcerated male (n = 265) and female (n = 149) offenders completed measures of psychiatric functioning and criminal thinking. Results indicated 92% of the participants were diagnosed with a serious mental illness, and mentally disordered offenders produced criminal thinking scores on the Psychological Inventory of Criminal Thinking Styles (PICTS) and Criminal Sentiments Scale-Modified (CSS-M) similar to that of non-mentally ill offenders. Collectively, results indicated the clinical presentation of mentally disordered offenders is similar to that of psychiatric patients and criminals. Implications are discussed with specific focus on the need for mental health professionals to treat co-occurring issues of mental illness and criminality in correctional mental health treatment programs.

Impact of intensified chemotherapy in metastatic pancreatic ductal adenocarcinoma (PDAC) in clinical routine in Europe

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is associated with poor prognosis. Gemcitabine is the standard chemotherapy for patients with metastatic pancreatic adenocarcinoma (MPA). Randomized clinical trials evaluating intensified chemotherapies including FOLFIRINOX and nab-paclitaxel plus gemcitabine (NAB+GEM) have shown improvement in survival. Here, we have evaluated the efficacy of intensified chemotherapy versus gemcitabine monotherapy in real-life settings across Europe.

METHODS

A retrospective multi-center study including 1056 MPA patients, between 2012 and 2015, from nine centers in UK, Germany, Italy, Hungary and the Swedish registry was performed. Follow-up was at least 12 months. Cox proportional Harzards regression was used for uni- and multivariable evaluation of prognostic factors.

RESULTS

Of 1056 MPA patients, 1030 (98.7%) were assessable for survival analysis. Gemcitabine monotherapy was the most commonly used regimen (41.3%), compared to FOLFIRINOX (n = 204, 19.3%), NAB+GEM (n = 81, 7.7%) and other gemcitabine- or 5-FU-based regimens (n = 335, 31.7%). The median overall survival (OS) was: FOLFIRINOX 9.9 months (95%CI 8.4-12.6), NAB+GEM 7.9 months (95%CI 6.2-10.0), other combinations 8.5 months (95%CI 7.7-9.3) and gemcitabine monotherapy 4.9 months (95%CI 4.4-5.6). Compared to gemcitabine monotherapy, any combination of chemotherapeutics improved the survival with no significant difference between the intensified regimens. Multivariable analysis showed an association between treatment center, male gender, inoperability at diagnosis and performance status (ECOG 1-3) with poor prognosis.

CONCLUSION

Gemcitabine monotherapy was predominantly used in 2012-2015. Intensified chemotherapy improved OS in comparison to gemcitabine monotherapy. In real-life settings, the OS rates of different treatment approaches are lower than shown in randomized phase III trials.

The clinical application of suicide risk assessment: A theory-driven approach

The interpersonal theory of suicide posits that thwarted belongingness (TB) and perceived burdensomeness (PB) increase suicide ideation; however, studies have found mixed results regarding this hypothesis among psychiatric inpatients. This study aimed to (a) demonstrate how assessing TB and PB using the Interpersonal Needs Questionnaire (INQ) can provide clinically useful information and (b) investigate how statistical methodology may impact the clinical application of the INQ. Participants were 139 (Sample 1) and 104 (Sample 2) psychiatric inpatients. In both samples, ordinal logistic regression results indicated TB and PB, separately, were significant predictors of suicide ideation-related outcomes; however, when examined as simultaneous predictors, TB was no longer a significant predictor. The interaction between TB and PB was not significant for either sample. Despite this, TB and PB scores provided clinically relevant information about suicide ideation-related outcomes. For example, the highest scores on TB and PB indicated a 93% and 95% chance of having some level of distress due to suicide ideation (Sample 1), a 91% and 92% chance of having some level of desire for death, and a 79% and 84% chance of having some level of desire for suicide, respectively (Sample 2). This study also proposes clinical cutoff scores for the INQ (for TB and PB, respectively, cutoff scores were 22 and 17 for distress due to suicide ideation, 33 and 17 for desire for death, and 31 and 22 for desire for suicide). Although these results indicate that multicollinearity between TB and PB may create interpretational ambiguity for clinicians, TB and PB may each be useful separate predictors of suicide ideation-related outcomes in psychiatric inpatient settings and should be incorporated into suicide risk assessment.

KEY PRACTITIONER MESSAGE

The 15-item Interpersonal Needs Questionnaire (an assessment of thwarted belongingness and perceived burdensomeness) should be incorporated into suicide risk assessment. Among psychiatric inpatients, greater thwarted belongingness and perceived burdensomeness, as separate predictors, were associated with increased levels of distress due to suicide ideation, desire for death, and desire for suicide. The highest scores on thwarted belongingness and perceived burdensomeness indicated a 79% to 95% chance of experiencing an elevated level of distress due to suicide ideation, desire for death, or desire for suicide. Recommended clinical cutoff scores were provided. For example, thwarted belongingness cutoff score of 31 and perceived burdensomeness cutoff score of 22 maximized the sensitivity and specificity of the INQ to detect some level of desire for suicide.

Palliative home parenteral nutrition in patients with ovarian cancer and malignant bowel obstruction: experiences of women and family caregivers

Background

Malnutrition is a problem in advanced cancer, particularly ovarian cancer where malignant bowel obstruction (MBO) is a frequent complication. Parenteral nutrition is the only way these patients can received adequate nutrition and is a principal indication for palliative home parenteral nutrition (HPN). Giving HPN is contentious as it may increase the burden on patients. This study investigates patients’ and family caregivers’ experiences of HPN, alongside nutritional status and survival in patients with ovarian cancer and MBO.

Methods

This mixed methods study collected data on participant characteristics, clinical details and body composition using computed tomography (CT) combined with longitudinal in-depth interviews underpinned by phenomenological principles. The cohort comprised 38 women with ovarian cancer and inoperable MBO admitted (10/2016 to 12/ 2017) to a tertiary referral hospital. Longitudinal interviews (n = 57) were carried out with 20 women considered for HPN and 13 of their family caregivers.

Results

Of the 38 women, 32 received parenteral nutrition (PN) in hospital and 17 were discharged on HPN. Nutritional status was poor with 31 of 33 women who had a CT scan having low muscle mass, although 10 were obese. Median overall survival from admission with MBO for all 38 women was 70 days (range 8–506) and for those 17 on HPN was 156 days (range 46–506).

Women experienced HPN as one facet of their illness, but viewed it as a “lifeline” that allowed them to live outside hospital. Nevertheless, HPN treatment came with losses including erosion of normality through an impact on activities of daily living and dealing with the bureaucracy surrounding the process. Family caregivers coped but were often left in an emotionally vulnerable state.

Conclusions

Women and family caregivers reported that the inconvenience and disruption caused by HPN was worth the extended time they had at home.

Functional analysis of iceA1, a CATG-recognizing restriction endonuclease gene in Helicobacter pylori

iceA1 in Helicobacter pylori is a homolog of nlaIIIR, which encodes the CATG-specific restriction endonuclease NlaIII in Neisseria lactamica. Analysis of iceA1 sequences from 49 H.pylori strains shows that a full-length NlaIII-like ORF is present in 10 strains, including CH4, but in other strains, including strain 60190, the ORFs are truncated due to a variety of mutations. Our goal was to determine whether iceA1 can encode a NlaIII-like endonuclease. Overexpression in Escherichia coli of iceA1 from CH4, but not from 60190, yielded NlaIII-like activity, indicating that the full-length iceA1 is a functional endonuclease gene. Repair of the iceA1 frameshift mutation in strain 60190 and its expression in E.coli yielded functional NlaIII-like activity. We conclude that iceA1 in CH4 is a functional restriction endonuclease gene, while iceA1 in 60190 is not, due to a frameshift mutation, but that its repair restores its restriction endonuclease activity.