Variant Tyr 394Ser in the GCM2 Gene Is Rare in a Cohort of Ashkenazi Jews With Primary Hyperparathyroidism

Context

Various genes have been associated with familial and sporadic primary hyperparathyroidism (PHPT), including activating mutations of the glial cells missing transcription factor 2 (GCM2) gene.

Objective

The aim of this study was to assess the prevalence of the GCM2 p.Tyr394Ser variant in the Jerusalem Ashkenazi Jewish (AJ) population with PHPT, and to conclude whether routine genetic testing is justified.

Methods

The blood of 40 self-reported AJ patients with PHPT and 200 AJ controls was tested for the GCM2 p.Tyr394Ser variant. Demographic and medical information was extracted from the patients' charts and evaluated accordingly.

Results

Two (5%) PHPT patients and 3 (1.5%) controls were heterozygotes for the tested variant. Our patients were mostly (87.5%) sporadic cases. One of the heterozygote patients had familial PHPT; the other had 2 parathyroid adenomas, and the levels of his blood and urinary calcium were extremely high.

Conclusion

Our results suggest that in AJ patients with sporadic, single-gland PHPT, the likelihood of the tested variant is low and genetic testing should be limited to those with familial PHPT or multiglandular disease.

Induction of periodontitis and oral microbiome dysbiosis in a mouse model with heart failure with preserved ejection fraction results in worsening hypertension and diastolic dysfunction

Introduction

Heart Failure with Preserved Ejection Fraction (HFpEF) is characterized by increased inflammation and disruption of the nitric oxide (NO) pathway. Oral microbiota has an essential role in the generation of a large portion of the NO bioavailability pool in the human body. Periodontitis (PD) is a common inflammatory condition that contributes to the development of chronic low-grade inflammation, oral microbiota dysbiosis, and dysregulation of the NO hemostasis.

Purpose

In this study, we sought to investigate the direct effect of PD induction on HFpEF manifestation in a mouse model.

Methods

HFpEF was induced in 11-week-old C57/black male mice by high-fat diet and inhibition of NO synthase using L-NAME (Nω-nitro-l-arginine-methyl-ester) (a “2-hit-model”) for 10 weeks. PD was induced by oral infection with P. gingivalis. Diastolic function of the left ventricle (LV) was assessed by high-frequency echocardiography. Blood pressure (BP) was measured using CODA non-invasive tail-cuff system.

Results

Induction of PD resulted in a significantly impaired diastolic function demonstrated by more pronounced decrease in e' and increase in E/e' ratio compared to HFpEF without PD or control mice (E/e': 39.7±2.6 vs. 30.1±1.9 vs. 24.3±2.1 for PD-HFpEF [n=15], HFpEF [n=15], and controls [n=10], respectively, p<0.001). While LV ejection fraction (EF) was similar, global longitudinal strain (GLS) was decreased in the HFpEF group and further decreased in the PD-HFpEF group compared to controls (p<0.001). BP was elevated in the HFpEF mice and PD induction resulted in a more remarkable increase in BP (systolic BP: 124.7±3.3 vs. 112.7±3.8 vs. 94.8±2.2 mmHg, respectively, p<0.001).

Conclusions

Induction of PD in a mouse model with HFpEF results in a more pronounced BP elevation and diastolic dysfunction compared to HFpEF without PD. Extensive molecular experiments are ongoing to explore the mechanisms responsible for the increased HFpEF severity in the setting of PD.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Israel Science Foundation

Amyloidosis of the aortic valve in patients with degenerative and bicuspid aortic stenosis

Introduction

Aortic stenosis (AS) is a common valvular disease, resulting in substantial morbidity and mortality. In younger patients, AS may occur as part of the bicuspid aortic valve (BAV) syndrome. Transthyretin cardiac amyloidosis (ATTR-CA) is an infiltrative disorder caused by the extracellular deposition of insoluble amyloid-derived fibrils. Recent studies have shown the presence of ATTR-CA in 4%-29% of degenerative AS patients. We hypothesized that amyloidosis may be involved in valve injury leading to AS.

Material and methods

We studied the aortic valves of 124 patients who underwent surgical aortic valve replacement at our institution over the last decade, included in our cardiosurgical database. Valves from 86 degenerative AS patients were compared to a control group of 38 patients with BAV stenosis. Patients with pure aortic regurgitation, history of rheumatic disease, or severe renal disease were excluded. The slides were stained with Congo red, and Thioflavin S then examined with regular, fluorescence and polarized light microscopy.

Results

In the degenerative AS group, Congo red and Thioflavin S staining was positive in 63% of the valves and 37% negative. The bicuspid AS group showed 68% positive and 32% negative for the Congo Red and Thioflavin S stains.

Discussion and conclusion

Our results indicate the presence of valvular amyloidosis in patients with AS, whether due to degenerative or congenital etiologies. This corroborates several recent studies. Intriguingly, there was an equally positive Congo red and Thioflavin S signal in bicuspid aortic valves. We speculate that the positive staining in the BAV group may indicate an inflammatory process associated with valve pathology inducing the accumulation of amyloid, and thus may not be transthyretin, as we expect in the experimental group. Another explanation may be that amyloidosis may be an epiphenomenon of valve “wear and tear” and not related to the pathogenesis in either etiology. Specific TTR immunofluorescence is underway to elucidate this question.

Funding Acknowledgement

Type of funding sources: None.

Alterations in the gut microbiota composition in the obesity phenotype of heart failure with preserved ejection fraction

Introduction

Obesity is one of the most common phenotypes of heart failure with preserved ejection fraction (HFpEF). A growing body of evidence indicates that obesity is characterized by compositional alterations in the intestinal microbiota and its metabolites, collectively referred as dysbiosis.

Purpose

We sought to investigate whether the obese phenotype of HFpEF is mediated by further alterations in the microbiota and whether gut dysbiosis fuels metabolic inflammation leading to progression of HFpEF.

Methods

HFpEF was induced in C57/black mice by high-fat diet and inhibition of NO synthesis (a “2-hit-model”) (Figure 1A). High-frequency echocardiography was performed to assess diastolic function. Blood pressure (BP) was measured using CODA non-invasive tail-cuff system. For human studies, patients with obese HFpEF as well as obese and non-obese healthy individuals were prospectively recruited. Gut microbial DNA was subjected to 16S ribosomal RNA gene sequencing, and the differences in abundance and composition of bacteria were defined both in humans and mice.

Results

In mice, the 2-hit model demonstrated significantly increased BP and impaired diastolic function in the obese HFpEF group (Figure 1B). Microbiome analysis showed significant differences in the gut microbial diversity and composition in the obese HFpEF compared to the non-HFpEF obese and chow-fed mice (Figure 1C). Similarly, human microbiome sequencing showed significant gut bacterial alterations in the diversity and composition of bacteria with more profound dysbiosis observed in the obese HFpEF patients compared to the obese and lean healthy individuals (Figure 1D).

Conclusions

We provide evidence in humans as well as in a murine animal model that the obese HFpEF phenotype is associated with more pronounced gut dysbiosis compared to the non-HFpEF obesity state. Further research will elucidate the causative link between gut dysbiosis and HFpEF manifestation and the mechanistic insights into the implication of gut microbiota in HFpEF progression.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Israel science foundation

Mitral regurgitation severity assessment after percutaneous edge-to-edge mitral valve repair: guidelines-recommended integration versus volumetric assessment

Background

Percutaneous edge-to edge mitral valve repair (PMVr) using the MitraClip device is a common method for treating mitral regurgitation (MR) when mitral valve operation is contra-indicated or deemed too risky. The evaluation of residual MR post PMVr is crucial for understanding the benefit and prognostic effect on patients. The common methods used today, based on color flow Doppler and the appearance of the color Doppler jet, may be misguiding because of the multiple jets created by the PMVr technique. Also, flow acceleration induced by the reduced systolic orifice may exaggerate systolic flow acceleration and thus jet area.

Purpose

We hypothesized that the guidelines-recommended method to assess MR may underestimate the effect of PMVr in reducing MR.

Methods

Patients undergoing PMVr in a large-volume PMVr centre were recruited between 2015–2019. Post procedural MR was evaluated using the integrated qualitative approach as recommended by the guidelines. In addition, MR volume for each patient was calculated by subtracting the forward stroke volume (calculated by multiplying LVOT area with the velocity time integral of LVOT systolic flow) from the total stroke volume (using the biplane method of discs), We compared the two methods for concordance.

Results

Overall, 112 cases were enrolled. In 59% of cases, the calculated volumetric residual MR was lower than the MR assessed by the integrated method. In 25.1% of patients the grade of MR was identical in both methods. In 16.2% the MR was more severe when calculated by the volumetric method (p<0.001, Kappa measure of agreement = 0.053–0.074). The reduction in residual MR degree using the volumetric approach was mostly observed in patients classified as “moderate” by the integrated qualitative approach. When considering basic characteristics and cardiac function of the patients, we did not find any sub-group of patients in whom the tendency for this mistake was higher.

Conclusion

Because of multiple jet origins and clip-induced flow acceleration, the integrated method to assess MR severity, based mainly on color Doppler, is not ideal in patients after PMVr. In most cases, MR severity after MitraClip is over-estimated by the integrated, guideline-recommended integrative method when compared with a volumetric method. This is especially relevant for patients classified with “moderate” MR. This study suggests that quantitative methods, not based on colour Doppler, should be used to assess MR severity after PMVr

Funding Acknowledgement

Type of funding sources: None.

Trusting our trainees: competency-based training of cardiologists using Entrustable Professional Activities (EPA)

 

Assessment of trainees is a core activity of educators, ensuring that trainees can be trusted to provide high quality care with no supervision. Training and the demands on trainees have changed with specialization, need for more technical skills, digitization, needs for teamwork and greater communication skills. Competency-based medical education was introduced to capture these changing needs for trainees.

The 7th ESC Education Conference – “From competence to good clinical care” – brought together national directors of training (39), young cardiology representatives (7), patients (7), ESC partners in education (10), and the ESC Education Committee (22) to discuss contemporary challenges in cardiology training and Entrustable Professional Activities (EPAs)-based solutions.

Methods

Pre- and post-conference surveys were conducted. The different issues were discussed in 4 workshops: core knowledge and evidence, skills and competence, performing into context, and training the trainers.

Results

Pre-conference, 90% of respondents believed that trainees should be certified only when they can be entrusted to perform in an unsupervised fashion, and 84% thought that specific training for educators should be required. From the workshops 4 themes emerged: 1) Core knowledge and evidence: rotations to different centres are needed to enable trainees to meet EPA requirements. 2) Skills and competence: a learning agreement between trainers and trainees should be established with protected time to achieve EPAs, and patient feedback on trainee performance should be obtained. 3) Performing into context (when is a trainee ready to practice): clinicians do informal assessment on a daily basis; EPAs formalize this with regular observation linked with progression in responsibility. 4) Train the trainer: good doctors are not automatically good trainers and should be required to undergo specific training themselves. We reviewed complex training frameworks such as the Canadian Medical Education Directives for Specialists (CanMEDS) that contains too many components to be useful for clinical teachers. EPAs were identified as a practical way to implement competency-based cardiology training across the ESC. The 2020 ESC Core Curriculum contains EPAs that a cardiologist should be able to perform independently by the end of training. Post-conference there was unanimous agreement (100%) that EPAs are a valuable concept in training. A majority of participants (69%) agreed that EPA's are applicable in practice today.

Conclusion

Trainee assessment is a daily challenge for educators. The ESC Education Conference identified distinct goals to be achieved before, during and at the completion of a training programs. The EPA concept was widely accepted as an efficient method to monitor trainees progress, while trusting them to perform activities in which they are proficient. Trusting our trainees should be a major educational goals for cardiologists in Europe.

Funding Acknowledgement

Type of funding source: None

MitraClip therapy in patients with acute severe mitral regurgitation

Background

There is a lack of data to support the optimal management of high-risk patients with acute severe mitral regurgitation (MR). The role of the MitraClip implantation in treatment of acute severe mitral regurgitation (MR) is undetermined.

Methods

We screened all patients who underwent MitraClip implantation at the Hadassah Medical Center between October 2015 and December 2019. We evaluated immediate, 30-day and 1-year outcomes after the procedure. We evaluated patients with severe MR due to ruptured cord because of degenerative disease and acute-on-chronic functional MR due to ischemic (after a recent myocardial infarction (MI)) or non-ischemic etiology (secondary to decompensated HF).

Results

From a cohort of 151 patients, who underwent MitraClip implantation in our center, we identified 35 patients (23.2%) with acute severe mitral regurgitation (4+) and decompensated refractory heart failure. Patients' mean age was 74.15 years, 66.9% - were males. One, 2, or 3 clips were implanted. Reduction of MR from 4+ to 1+ was achieved in 34 patients (66.7%). Twenty-eight patients (80%) had acute-on-chronic severe MR and refractory heart failure including 6 cases after recent MI, other 7 patients presented with heart failure and acute severe MR secondary to ruptured cord due to degenerative disease. After MitraClip implantation, reduction of MR severity was achieved in all patients. Seven patients were withdrawn from intravenous therapy and intra-aortic balloon pump 2–3 days after the procedure. Four patients died during hospitalization, three of them due to sepsis. 30-day follow-up showed improvement of NYHA functional class and a tendency toward improvement in left ventricle systolic function with signs of reverse remodeling. Nevertheless, we observed high 30-day and 1-year mortality rate (11.4 and 23.8% respectively).

Conclusions

MitraClip therapy could be an alternative option for treatment of patients with acute and acute-on-chronic severe MR of ischemic and non-ischemic etiology.

Funding Acknowledgement

Type of funding source: None

Echocardiographic and clinical outcomes of MitraClip therapy in patients with severe mitral regurgitation

Background

MitraClip implantation improves mitral regurgitation (MR), however its impact on pulmonary hypertension (PHT) is not fully elucidated. Our hypothesis was that changes in pulmonary pressure after MitraClip implantation might predict outcomes.

Methods

We studied a cohort of 149 consecutive patients who underwent MitraClip implantation between August 2015 and September 2019. We compared echocardiographic and clinical variables between a group with not-severe PHT and a group with severe PHT according to Pulmonary artery systolic pressure (PASP) >55 mmHg.

Results

Mean age of the cohort was 73±10 years, 75% were men, and 80% had functional MR. There are no differences in baseline characteristics between the two groups. There was a significant reduction of 13.6 mmHg in PASP at the severe PHT group from 68.2±10.9 mmHg before the procedure to 54.6±14.9 after (P=0.001) compared to the absence of a significant change in the second group. This reduction was maintained in the 6 months follow-up. Although PHT is considered a poor prognostic measure, and the severe PHT group had a baseline PASP higher than the not-severe group (P<0.001), however the Kaplan Meier curve did not show any significant difference in overall survival (p=0.468), and there is also no difference in one-year survival.

Conclusions

MitraClip therapy improves PASP in patients with severe MR and severe PHT. These patients showed the same survival as patients with not-severe PHT. MitraClip is a safety and effective procedure even for patients with severe PHT, that should not be excluded.

Funding Acknowledgement

Type of funding source: None

Novel WWOX deleterious variants cause early infantile epileptic encephalopathy, severe developmental delay and dysmorphism among Yemenite Jews

The human WW Domain Containing Oxidoreductase (WWOX) gene was originally described as a tumor suppressor gene. However, recent reports have demonstrated its cardinal role in the pathogenesis of central nervous systems disorders such as epileptic encephalopathy, intellectual disability, and spinocerebellar ataxia. We report on six patients from three unrelated families of full or partial Yemenite Jewish ancestry exhibiting early infantile epileptic encephalopathy and profound developmental delay. Importantly, four patients demonstrated facial dysmorphism. Exome sequencing revealed that four of the patients were homozygous for a novel WWOX c.517-2A > G splice-site variant and two were compound heterozygous for this variant and a novel c.689A > C, p.Gln230Pro missense variant. Complementary DNA sequencing demonstrated that the WWOX c.517-2A > G splice-site variant causes skipping of exon six. A carrier rate of 1:177 was found among Yemenite Jews. We provide the first detailed description of patients harboring a splice-site variant in the WWOX gene and propose that the clinical synopsis of WWOX related epileptic encephalopathy should be broadened to include facial dysmorphism. The increased frequency of the c.517-2A > G splice-site variant among Yemenite Jews coupled with the severity of the phenotype makes it a candidate for inclusion in expanded preconception screening programs.

Mitochondrial PITRM1 peptidase loss-of-function in childhood cerebellar atrophy

OBJECTIVE

To identify the genetic basis of a childhood-onset syndrome of variable severity characterised by progressive spinocerebellar ataxia, mental retardation, psychotic episodes and cerebellar atrophy.

METHODS

Identification of the underlying mutations by whole exome and whole genome sequencing. Consequences were examined in patients' cells and in yeast.

RESULTS

Two brothers from a consanguineous Palestinian family presented with progressive spinocerebellar ataxia, mental retardation and psychotic episodes. Serial brain imaging showed severe progressive cerebellar atrophy. Whole exome sequencing revealed a novel mutation: pitrilysin metallopeptidase 1 (PITRM1) c.2795C>T, p.T931M, homozygous in the affected children and resulting in 95% reduction in PITRM1 protein. Whole genome sequencing revealed a chromosome X structural rearrangement that also segregated with the disease. Independently, two siblings from a second Palestinian family presented with similar, somewhat milder symptoms and the same PITRM1 mutation on a shared haplotype. PITRM1T931M carrier frequency was 0.027 (3/110) in the village of the first family evaluated, and 0/300 among Palestinians from other locales. PITRM1 is a mitochondrial matrix enzyme that degrades 10-65 amino acid oligopeptides, including the mitochondrial fraction of amyloid-beta peptide. Analysis of peptide cleavage activity by the PITRM1T931M protein revealed a significant decrease in the degradation capacity specifically of peptides ≥40 amino acids.

CONCLUSION

PITRM1T931M results in childhood-onset recessive cerebellar pathology. Severity of PITRM1-related disease may be affected by the degree of impairment in cleavage of mitochondrial long peptides. Disruption and deletion of X linked regulatory segments may also contribute to severity.

Features of Patients With Hereditary Mixed Polyposis Syndrome Caused by Duplication of GREM1 and Implications for Screening and Surveillance

Hereditary mixed polyposis syndrome is a rare colon cancer predisposition syndrome caused by a duplication of a noncoding sequence near the gremlin 1, DAN family BMP antagonist gene (GREM1) originally described in Ashkenazi Jews. Few families with GREM1 duplications have been described, so there are many questions about detection and management. We report 4 extended families with the duplication near GREM1 previously found in Ashkenazi Jews; 3 families were identified at cancer genetic clinics in Israel and 1 family was identified in a cohort of patients with familial colorectal cancer. Their clinical features include extracolonic tumors, onset of polyps in adolescence, and rapid progression of some polyps to advanced adenomas. One family met diagnostic criteria for Lynch syndrome. Expansion of the hereditary mixed polyposis syndrome phenotype can inform surveillance strategies for carriers of GREM1 duplications.

A role for TENM1 mutations in congenital general anosmia

Congenital general anosmia (CGA) is a neurological disorder entailing a complete innate inability to sense odors. While the mechanisms underlying vertebrate olfaction have been studied in detail, there are still gaps in our understanding of the molecular genetic basis of innate olfactory disorders. Applying whole-exome sequencing to a family multiply affected with CGA, we identified three members with a rare X-linked missense mutation in the TENM1 (teneurin 1) gene (ENST00000422452:c.C4829T). In Drosophila melanogaster, TENM1 functions in synaptic-partner-matching between axons of olfactory sensory neurons and target projection neurons and is involved in synapse organization in the olfactory system. We used CRISPR-Cas9 system to generate a Tenm1 disrupted mouse model. Tenm1(-/-) and point-mutated Tenm1(A) (/A) adult mice were shown to have an altered ability to locate a buried food pellet. Tenm1(A) (/A) mice also displayed an altered ability to sense aversive odors. Results of our study, that describes a new Tenm1 mouse, agree with the hypothesis that TENM1 has a role in olfaction. However, additional studies should be done in larger CGA cohorts, to provide statistical evidence that loss-of-function mutations in TENM1 can solely cause the disease in our and other CGA cases.

An intronic haplotype in α galactosidase A is associated with reduced mRNA expression in males with cryptogenic stroke

Persons with unexplained early-onset stroke have been targeted for screening surveys for Fabry disease, the most common of the three X-linked lysosomal disorders, because Fabry patients with stroke are more likely to have the life-threatening progressive cardiac and renal manifestations and would therefore most benefit from early diagnosis and intervention with enzyme replacement therapy (ERT). Among 175 Israeli patients with unexplained cryptogenic stroke screened for mutations in the Fabry α galactosidase A (GLA) gene, sequencing identified six with 2-4 GLA intronic variants, one of whose father and three sisters had the same variants. Two variants, c.640-16A>G (g.10115A>G) in intron 4 and c.1000-22C>T (g.10956C>T) in intron 6, were common to all patients. However, three males with a common four variant intronic haplotype had low residual enzyme activity and ~50% reduced mRNA expression. Transcript splice-site defects were not identified in any of the index cases and X-chromosome inactivation was not highly skewed in the six females. These data do not suggest that GLA intronic variants, per se, are pathogenic. Nonetheless, it is clear that a certain intronic haplotype in males with cryptogenic stroke is associated with reduced GLA expression and function.

Thiopurine S-methyltransferase (TPMT) activity is better determined by biochemical assay versus genotyping in the Jewish population

BACKGROUND

Thiopurine S-methyltransferase (TPMT) is a key enzyme that deactivates thiopurines, into their inactive metabolite, 6-methylmercaptopurine. Intermediate and low TPMT activity may lead to leukopenia following thiopurine treatment. The aim of this study was to determine TPMT activity and TPMT alleles (genotype-phenotype correlation) in Jews, aiming to develop an evidence-based pharmacogenetic assay for this population.

METHODS

TPMT activity was determined in 228 Jewish volunteers by high performance liquid chromatography. Common allelic variants in the Caucasian population [TPMT*2 (G238C), TPMT *3A (G460A and A719G), TPMT* 3B (G460A) and TPMT*3C (A719G)] were tested. Phenotype-genotype correlation was examined and discordant cases were fully sequenced to identify novel genetic variants.

RESULTS

Mean TPMT activity was 15.4 ± 4 U/ml red blood cells (range 1-34). Intermediate activity was found in 33/228 (14%) subjects and absent activity was found in one sample (0.4%). Only eight individuals (3.5% of the entire cohort and 24% of those with intermediate/low activity) were identified as carriers of a TPMT genetic variant, all of whom had the TPMT*3A allele. Sequencing the entire TPMT coding region and splice junctions in the remainder of the discordant cases did not reveal any novel variants.

CONCLUSION

Genotyping TPMT in Jews yields a much lower rate of variants than identified in the general Caucasian population. We conclude that a biochemical assay to determine TPMT enzymatic activity should be performed in Jews before starting thiopurine treatment in order to identify low activity subjects.

Female sex bias in human embryonic stem cell lines

The factors limiting the rather inefficient derivation of human embryonic stem cells (HESCs) are not fully understood. The aim of this study was to analyze the sex ratio in our 42 preimplantation genetic diagnosis (PGD)-HESC lines, in an attempt to verify its affect on the establishment of HESC lines. The ratio between male and female PGD-derived cell lines was compared. We found a significant increase in female cell lines (76%). This finding was further confirmed by a meta-analysis for combining the results of all PGD-derived HESC lines published to date (148) and all normal karyotyped HESC lines derived from spare in vitro fertilization embryos worldwide (397). Further, gender determination of embryos demonstrated that this difference originates from the actual derivation process rather than from unequal representation of male and female embryos. It can therefore be concluded that the clear-cut tendency for female preponderance is attributed to suboptimal culture conditions rather than from a true gender imbalance in embryos used for derivation of HESC lines. We propose a mechanism in which aberrant X chromosome inactivation and/or overexpression of critical metabolic X-linked genes might explain this sex dimorphism.

Preimplantation genetic diagnosis (PGD)--prevention of the birth of children affected with endocrine diseases

OBJECTIVE

To develop a reliable and accurate preimplantation genetic diagnosis (PGD) method in six families with endocrine diseases: persistent hyperinsulinemic hypoglycemia of infancy (PHHI), congenital adrenal hyperplasia (CAH) salt-wasting form, Sanjat-Sakati syndrome and multiple endocrine neoplasia 2A (MEN 2A).

METHODS

For each disease a battery of at least four informative markers surrounding the tested gene were identified and for each family a protocol of multiplex fluorescent markers was developed and performed on single cells.

RESULTS

PGD for PHHI was performed in three families. In family 1 two healthy children were born from different cycles, in family 2 three healthy children were born from two cycles, and in family 3 a healthy boy was born. For CAH in one family a healthy girl was born. One PGD cycle for Sanjat-Sakati resulted in a clinical pregnancy that was terminated due to high nuccal translucency (46X0). For one family with MEN 2A disease, the eighth PGD cycle resulted in birth of healthy twins. In all children genetic confirmation of the healthy status was performed.

CONCLUSIONS

PGD is an effective method for preventing birth of affected children with endocrine disorders. Increasing the awareness of clinicians to the availability of these methods is most important.

The CYP17A1 -34T > C polymorphism and breast cancer risk in BRCA1 and BRCA2 mutation carriers

Exposure to estrogen has a major effect on breast cancer risk. A polymorphism (-34 T > C; rs743572) in the cytochrome P450c17alpha gene (CYP17A1) encoding an enzyme which controls estrogen levels was reportedly associated with breast cancer risk in average risk populations. The effect of this polymorphism on breast or ovarian cancer risk for BRCA1 and BRCA2 mutation carriers has not been thoroughly investigated. With this aim, 2,221 BRCA1 and BRCA2 mutation carriers (1,313 with breast cancer, 279 with ovarian cancer, and 695 asymptomatic carriers), with either BRCA1 (n = 1693) or BRCA2 (n = 528) germline mutations from seven centers were genotyped for the -34 T > C CYP17 polymorphism. Genotyping was accomplished using Taqman allelic discrimination, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) or PCR-based restriction-fragment length polymorphism analysis, and limited sequencing. Data were analyzed using Cox proportional hazards models. The hazard ratios (HRs) for breast cancer was 1.02 (95% CI 0.89-1.17, p = 0.74) and 1.10 (95% CI 0.72-1.67, p = 0.66) for BRCA1 and BRCA2 mutation carriers, respectively. The HRs for ovarian cancer were 1.17 (0.94-1.46, p = 0.17) and 0.91 (0.31-2.67, p = 0.86) for BRCA1 and BRCA2 mutation carriers, respectively. Results remained unaltered when the Israeli cohort (primarily Ashkenazim) was evaluated separately. In conclusion, there was no overall evidence for an association of the -34 T > C CYP17 polymorphism with either breast or ovarian cancer risk in BRCA1 or BRCA2 mutation carriers.

Preimplantation genetic diagnosis (PGD) for a treatable disorder: Gaucher disease type 1 as a model

BACKGROUND

Preimplantation genetic diagnosis (PGD) is a technique that enables identification of unaffected embryos prior to in vitro fertilization (IVF) transfer in couples at risk for a Mendelian disorder. Most cases involve severe genetic diseases with neurological features and/or major malformations. We present two couples in which PGD was performed for prevention of type 1 Gaucher disease, a non-neuronopathic, non-lethal disorder.

MATERIALS AND METHODS

We developed a multiplex fluorescent PCR protocol, simultaneously amplifying the familial mutations and eight closely spaced, highly polymorphic informative microsatellite markers surrounding the gene, to be used for PGD analysis.

RESULTS

Couple #1 mother was homozygous for the N370S mutation and the father carried the 84GG mutation; their first daughter receives specific Gaucher therapy. One PGD cycle resulted in seven embryos of which four had the paternal wild type allele; two were transferred resulting in a healthy baby boy born at term. Couple #2, each a carrier (N370S and R359Q), whose first-born child had died (age 5years) of Gaucher disease, underwent 7 PGD cycles. Only one cycle resulted in a clinical pregnancy but a miscarriage was followed at 10weeks.

CONCLUSIONS

PGD is an effective and accurate method for preventing Gaucher disease type I in carrier couples. Since this disease is treatable, special ethical considerations and careful selection of couples should be performed.

Functional variant of KLOTHO: a breast cancer risk modifier among BRCA1 mutation carriers of Ashkenazi origin

Klotho is a transmembrane protein that can be shed and act as a circulating hormone and is a putative tumor suppressor in breast cancer. A functional variant of KLOTHO (KL-VS) contains two amino acid substitutions F352V and C370S and shows reduced activity. Germ-line mutations in BRCA1 and BRCA2 substantially increase lifetime risk of breast and ovarian cancers. Yet, penetrance of deleterious BRCA1 and BRCA2 mutations is incomplete even among carriers of identical mutations. We examined the association between KL-VS and cancer risk among 1115 Ashkenazi Jewish women: 236 non-carriers, 631 BRCA1 (185delAG, 5382insC) carriers and 248 BRCA2 (6174delT) carriers. Among BRCA1 carriers, heterozygosity for the KL-VS allele was associated with increased breast and ovarian cancer risk (hazard ratio 1.40, 95% confidence intervals 1.08-1.83, P=0.01) and younger age at breast cancer diagnosis (median age 48 vs 43 P=0.04). KLOTHO and BRCA2 are located on 13q12, and we identified linkage disequilibrium between KL-VS and BRCA2 6174delT mutation. Studies in breast cancer cells showed reduced growth inhibitory activity and reduced secretion of klotho F352V compared with wild-type klotho. These data suggest KL-VS as a breast and ovarian cancer risk modifier among BRCA1 mutation carriers. If validated in additional cohorts, the presence of KL-VS may serve as a predictor of cancer risk among BRCA1 mutation carriers.

Egr-1 upregulates the Alzheimer's disease presenilin-2 gene in neuronal cells

Regulation of the Alzheimer's disease (AD)-related gene, presenilin-2 (PSEN2), was analyzed in neuronal (SK-N-SH) and non-neuronal (human embryonic kidney 293, HEK293) cells. We show that the PSEN2 regulatory region includes two separate promoter elements, each located upstream of multiple transcription start sites in the first and second exons. The stronger upstream promoter, P1, has housekeeping characteristics: it resides in a CpG island, is TATA-less, and up to 83% of PSEN2-P1 activity depends on a stimulating protein 1 (Sp1) site at the most 5' initiation site. However, the downstream promoter P2 includes neuronal-specific elements and two sites for early growth response gene-1 (Egr-1), a transcription factor upregulated in learning paradigms and implicated in neuronal plasticity, in response to injury. We show that Egr-1 binds to PSEN-P2, and that PSEN-P2 activity is increased threefold by overexpression of Egr-1, and by 12-O-tetradecanoylphorbol-13-acetate (TPA), which induces physiological Egr-1 levels. Egr-1 represses PSEN2-P1 activity by 50% in neuronal cells, suggesting it partially shifts promoter usage from PSEN2-P1 to PSEN2-P2. This could lead to a relative increase in shorter exon 2 transcripts, which may be more efficiently translated than exon 1 transcripts. Identification of PSEN2 as an Egr-1 target suggests a link between PSEN2 expression and Egr-1-related processes, which may impact on understanding PSEN-2's physiological function and its role in Alzheimer's disease.

Transgenic acetylcholinesterase induces enlargement of murine neuromuscular junctions but leaves spinal cord synapses intact

Acetylcholinesterase (AChE) produced by spinal cord motoneurons accumulates within axo-dendritic spinal cord synapses. It is also secreted from motoneuron cell bodies, through their axons, into the region of neuromuscular junctions, where it terminates cholinergic neurotransmission. Here we show that transgenic mice expressing human AChE in their spinal cord motoneurons display primarily normal axo-dendritic spinal cord cholinergic synapses in spite of the clear excess of transgenic over host AChE within these synapses. This is in contrast to our recent observation that a modest excess of AChE drastically affects the structure and long-term functioning of neuromuscular junctions in these mice although they express human AChE in their spinal cord, but not muscle. Enlarged muscle endplates with either exaggerated or drastically shortened post-synaptic folds then lead to a progressive neuromotor decline and massive amyotrophy (Andres et al., 1997). These findings demonstrate that excess neuronal AChE may cause distinct effects on spinal cord and neuromuscular synapses and attribute the late-onset neuromotor deterioration observed in AChE transgenic mice to neuromuscular junction abnormalities.

Pituitary apoplexy as a first manifestation of pituitary adenomas following intensive thrombolytic and antithrombotic therapy

Apoplexy of a previously asymptomatic pituitary macroadenoma may occur in the setting of intensive thrombolytic, antithrombotic, or anticoagulant therapy for acute myocardial infarction. Classic clinical findings may initially be nonspecific and a high index of suspicion is therefore required for early diagnosis.

Enhanced hemicholinium binding and attenuated dendrite branching in cognitively impaired acetylcholinesterase-transgenic mice

In a search for behavioral, neuroanatomical, and metabolic characteristics of Alzheimer's disease that may result from cholinergic malfunction, we used transgenic mice overexpressing acetylcholinesterase (AChE) mRNA and active enzyme in brain neurons. Mapping by in situ hybridization revealed that transgenic and host AChE mRNAs were distributed similarly. In a Morris water maze working memory paradigm, adult transgenic mice did not display the characteristic improvement found in control mice either between or within test days and spent less time than control mice in the platform zone. In 5-week-old transgenic mice, the basilar dendritic trees of layer 5 pyramidal neurons from the frontoparietal cortex were essentially as developed as in age-matched controls. However, branching totally ceased after this age, whereas in control adults it continued up to at least 7 months. Therefore, dendritic arbors became smaller in adult transgenic mice than those of controls. Furthermore, the average number of spines was significantly lower on dendritic branches of 7-month-old but not 5-week-old transgenics as compared with controls. Binding of tritiated hemicholinium-3, a blocker of the high-affinity choline uptake characteristic of active cholinergic terminals, was over twofold enhanced in the brain of transgenic mice. In contrast, no differences were observed in the mRNA and ligand binding levels of several different subtypes of nicotinic and muscarinic acetylcholine receptors. These findings suggest that three different hallmarks associated with Alzheimer's disease--namely, progressive cognitive failure, cessation of dendrite branching and spine formation, and enhanced high-affinity choline uptake--are outcomes of cholinergic malfunction.

Frequent apoptosis in human kidneys after acute renal hypoperfusion

BACKGROUND/AIMS

Apoptosis, a form of cell death characterized by DNA fragmentation and minimal inflammation, is induced by intrarenal hypoxia in rats. The objective of this study was to test whether apoptosis participates in human acute renal injury.

METHODS

We examined kidneys obtained from autopsies of 40 patients following hemodynamic compromise and from 9 controls following sudden death. Nuclear DNA fragmentation was assayed by in situ 3' end labeling (TUNEL stain) and compared to histological findings.

RESULTS

DNA fragmentation along renal tubular cells was observed in 23 (57%) of the study patients but in none of the controls (p < 0.005). Acute tubular necrosis was seen by formal histology in 27% of the patients and correlated with clinical acute renal dysfunction, while DNA fragmentation did not.

CONCLUSION

DNA fragmentation often occurs after renal hypoperfusion and does not imply renal failure. Apoptosis may participate in the adaptive response of the kidney to hypoxia.

Acetylcholinesterase-transgenic mice display embryonic modulations in spinal cord choline acetyltransferase and neurexin Ibeta gene expression followed by late-onset neuromotor deterioration

To explore the possibility that overproduction of neuronal acetylcholinesterase (AChE) confers changes in both cholinergic and morphogenic intercellular interactions, we studied developmental responses to neuronal AChE overexpression in motoneurons and neuromuscular junctions of AChE-transgenic mice. Perikarya of spinal cord motoneurons were consistently enlarged from embryonic through adult stages in AChE-transgenic mice. Atypical motoneuron development was accompanied by premature enhancement in the embryonic spinal cord expression of choline acetyltransferase mRNA, encoding the acetylcholine-synthesizing enzyme choline acetyltransferase. In contrast, the mRNA encoding for neurexin-Ibeta, the heterophilic ligand of the AChE-homologous neuronal cell surface protein neuroligin, was drastically lower in embryonic transgenic spinal cord than in controls. Postnatal cessation of these dual transcriptional responses was followed by late-onset deterioration in neuromotor performance that was associated with gross aberrations in neuromuscular ultrastructure and with pronounced amyotrophy. These findings demonstrate embryonic feedback mechanisms to neuronal AChE overexpression that are attributable to both cholinergic and cell-cell interaction pathways, suggesting that embryonic neurexin Ibeta expression is concerted in vivo with AChE levels and indicating that postnatal changes in neuronal AChE-associated proteins may be involved in late-onset neuromotor pathologies.

Failure of insulin-like growth factor 1 to improve radiocontrast nephropathy

Exogenous insulin-like growth factor 1 (IGF-1) has been reported to improve experimental ischemic acute renal failure. We investigated a possible beneficial role of IGF-1 in a model of radiocontrast nephropathy induced by indomethacin, nitro-L-arginine ester and iothalamate. Multiple injections of recombinant human IGF-1 (or its vehicle) at 150 microg/100 g body weight/day were given for 24 h starting 1 h after radiocontrast, or initiated 1 day after the insults and continued for 48 h. IGF-1 prevented neither the fall in creatinine clearance nor medullary thick ascending limb necrosis observed at 24 h. Similarly IGF-1, given for 2 days after renal failure had been established, did not accelerate functional recovery at 72 h, did not ameliorate catabolism and did not alter the morphological evolution of intrarenal damage. In conclusion, IGF-1 had no beneficial effects in this model of radiocontrast nephropathy.

Left ventricular free wall rupture as the presenting manifestation of acute myocardial infarction in diabetic patients

We present 5 diabetic patients with acute myocardial infarction in whom left ventricular free wall rupture was the presenting manifestation. Echocardiography may be indicated in diabetic patients with acute myocardial infarction and in shock, prior to thrombolysis.

Transgenic expression of human acetylcholinesterase induces progressive cognitive deterioration in mice

BACKGROUND

Cognitive deterioration is a characteristic symptom of Alzheimer's disease. This deterioration is notably associated with structural changes and subsequent cell death which occur, primarily, in acetylcholine-producing neurons, progressively damaging cholinergic neurotransmission. We have reported previously that excess acetylcholinesterase (AChE) alters structural features of neuromuscular junctions in transgenic Xenopus tadpoles. However, the potential of cholinergic imbalance to induce progressive decline of memory and learning in mammals has not been explored.

RESULTS

To approach the molecular mechanisms underlying the progressive memory deficiencies associated with impaired cholinergic neurotransmission, we created transgenic mice that express human AChE in brain neurons. With enzyme levels up to two-fold higher than in control mice, transgenic mice displayed an age-independent resistance to the hypothermic effects of the AChE inhibitor, paraoxon. In addition to this improved scavenging capacity for anti-AChEs, however, these transgenic mice also resisted muscarinic, nicotinic and serotonergic agonists, indicating that secondary pharmacological changes had occurred. The transgenic mice also developed progressive learning and memory impairments, although their locomotor activities and open-field behaviour remained similar to those of matched control mice. By six months of age, transgenic mice lost their ability to respond to training in a spatial learning water maze test, whereas they performed normally in this test at the age of four weeks. This animal model is therefore suitable for investigating the transcriptional changes associated with cognitive deterioration and for testing drugs that may attenuate progressive damage.

CONCLUSION

We conclude that upsetting cholinergic balance may by itself cause progressive memory decline in mammals, suggesting that congenital and/or acquired changes in this vulnerable balance may contribute to the physiopathology of Alzheimer's disease.

Rapid DNA fragmentation from hypoxia along the thick ascending limb of rat kidneys

Extensive DNA fragmentation, a marker for programmed cell death, was selectively and rapidly induced by hypoxia in the thick ascending limbs of rat kidneys. In isolated perfused kidneys, DNA breaks were present in medullary tubules as early as after 10 minutes of local hypoxia and were prevented by reduction of metabolic work. In a model of radiocontrast-induced acute renal failure, DNA breaks were detected selectively along thick ascending limbs as early as 15 minutes following insult, preceding overt morphological damage. Hypoxia induces rapid DNA fragmentation along thick ascending limbs, where programmed cell death could play an important role in nephron injury and kidney failure.

Predictors of mortality in patients admitted to hospital for acute upper gastrointestinal hemorrhage

BACKGROUND

We wanted to identify features of prognostic significance in patients admitted to hospital because of acute upper gastrointestinal (UGI) hemorrhage.

METHODS

A prospective, longitudinal study of 321 consecutive cases admitted during 1988-91 was carried out. The relative risk of mortality associated with each of the background, laboratory, and endoscopic features and the hospital course was calculated. Multiple stepwise logistic regression was used to define factors independently associated with mortality. Two models were evaluated, the first based on the data at presentation (history, physical findings, initial laboratory data) and the second based on the first, plus the endoscopic and follow-up data.

RESULTS

The overall mortality was 7.8%. At presentation the features associated with a significantly (p < 0.05) increased risk of mortality were (adjusted odds ratios in parentheses) age > or = 75 years (11.2), a history of cancer (12.1), blood in the gastric aspirate (9.6), and a systolic blood pressure < or = 90 mm Hg (6.4). The overall predictors of mortality were age > or = 75 years (12.7), blood in the gastric aspirate (18.9), serum creatinine level > or = 150 mumol/l (14.8), increased serum aminotransferase level (20.2), and persistent or recurrent bleeding (57.3).

CONCLUSIONS

In patients admitted to hospital because of UGI hemorrhage the prognosis depends on age, underlying diseases, hemodynamic status, and the persistence or recurrence of bleeding. The causes of bleeding were not relevant to the prognosis.

Testicular amplification and impaired transmission of human butyrylcholinesterase cDNA in transgenic mice

Gene amplification occurs frequently in tumour tissues yet is, in general, non-inheritable. To study the molecular mechanisms conferring this restraint, we created transgenic mice carrying a human butyrylcholinesterase (BCHE) coding sequence, previously found to be amplified in a father and son. Blot hybridization of tail DNA samples revealed somatic transgene amplifications with variable restriction patterns and intensities, suggesting the occurrence of independent amplification events, in 31% (11/35) of mice from the FII generation but in only 3.5% (2/58) of the FIII and FIV generations. In contrast, > 10-fold amplifications of the BCHE transgene and the endogenous acetylcholinesterase and c-raf genes appeared in both testis and epididymis DNA from > 80% of FIII mice. Drastic, selective reductions in testis BCHEmRNA but not in actin mRNA were detected by the PCR amplification of testis cDNA from the transgenic mice, and apparently resulted in the limited transmission of amplified genes. The testicular amplification of the BCHE transgene may potentially represent a general phenomenon with clinical implications in human infertility.

Acute upper gastrointestinal bleeding in Jerusalem 1988-91: causes, characteristics and relation to nonsteroidal anti-inflammatory drugs

We analyzed 321 consecutive episodes of community-based acute upper gastrointestinal bleeding admitted to the Hadassah University Hospital in Jerusalem during 1988-91. Of these 71% were in males aged 56.2 +/- 1.2 years (mean +/- SE) and 29% were in females (67.9 +/- 1.7 years, P < 0.001). The main diagnoses were duodenal ulcer (39.5%), gastric ulcer (16.9%), esophageal varices (10.0%), erosive gastritis (8.2%) and esophagitis (7.5%). The distribution of these diagnoses differed significantly between the genders (P = 0.0003). In males the prevalence of duodenal ulcer and of esophageal varices was higher, and that of gastric ulcer and esophagitis lower, than in females. Gastric ulcer patients were oldest, were the least likely to have received anti-ulcer medications prior to admission, and had the highest levels of urea and the lowest levels of hemoglobin on admission. Use of nonsteroidal anti-inflammatory drugs increased significantly with age and was reported in 35% of the cases (aspirin in doses < 1.0 g/day in 21%, nonsalicylate anti-inflammatory agents in 11%, aspirin plus other anti-inflammatory drugs in 3%). Use of systemic corticosteroids was reported in 4%. The most distinctive features of the population with acute upper gastrointestinal bleeding in the present study compared to other series were the significantly higher proportion of duodenal ulcers and the lower proportion of Mallory-Weiss tears.

Seasonal fluctuations in acute upper gastrointestinal bleeding: lack of effect of nonsteroidal anti-inflammatory drugs

The seasonal pattern of community-based acute bleeding from the upper gastrointestinal (UGI) tract was studied prospectively in 1988-1991. Out of 3343 emergency admissions to the Departments of General Surgery, 321 (9.6%) were due to acute UGI bleeding. There was a significant monthly variation in the total number of admissions, as well as in the number of admissions due to acute UGI bleeding (p < 0.0001). However, there was no correlation between the two. Significant seasonal fluctuations were noted both in the absolute number of admissions due to acute UGI bleeding and in the percentage of UGI bleeding admissions of the total number of admissions to the Departments of General Surgery (p = 0.0002). During summer (July through September), the incidence declined significantly to a nadir of 5.5% of total number of admissions in July. The seasonal fluctuation correlated closely with the incidence of duodenal ulcer, but not with that of gastric ulcer. The seasonal pattern was consistent both in patients who had used aspirin or other nonsteroidal anti-inflammatory drugs as well as in those who had not.

In vivo gene amplification in non-cancerous cells: cholinesterase genes and oncogenes amplify in thrombocytopenia associated with lupus erythematosus

The ACHE and BCHE genes, encoding the acetylcholine hydrolysing enzymes acetylcholinesterase (ACHE) and butyrylcholinesterase (BCHE), co-amplify with several oncogenes in leukemic patients with platelet deficiency (thrombocytopenia). This and other experiments implicated ACHE and BCHE in the development of bone marrow megakaryocytes, the progenitors of platelets. Therefore, we wished to find out whether cholinesterase gene amplification would also occur in non-cancerous platelet disorders and, if so, whether oncogenes would amplify in such cases as well. The autoimmune disease systemic lupus erythematosus (SLE) presents an appropriate model system for this issue, since patients with SLE may suffer from thrombocytopenia resistant to most treatment modalities. Here, we report a 40-80-fold amplification of genomic sequences from the ACHE and BCHE genes as well as the C-raf, V-sis and C-fes/fps oncogenes in peripheral blood cells from an SLE patient with severe thrombocytopenia. PvuII restriction analysis and DNA blot hybridization of the amplified ACHE and BCHE sequences demonstrated apparent aberrations in both genes, suggesting that malfunctioning of modified, partially amplified cholinesterase genes may be involved in the etiology of thrombocytopenia associated with SLE. These observations imply that cholinergic mechanisms regulate megakaryocytopoiesis, shed new light on the diverse hematologic findings characteristic of SLE, and may become valuable as diagnostic, treatment and prognostic tools in the follow-up of patients suffering from thrombocytopenia associated with SLE. Furthermore, these findings reinforce the notion that cholinesterase gene amplifications are causally related with platelet abnormalities in multiple hemopoietic disorders.