[Priapism associated to zuclopentixol and the choice for an alternative]

A 29-year-old man developed priapism following the (re)administration of zuclopentixol. In the previous days, a significant amount of alcohol was consumed, presumably in combination with amphetamine and cannabis. Priapism is a rare but serious side effect of various psychoactive medications and recreational drugs, leading to permanent loss of erectile function if not treated in time. In this case the side effect was discovered in a late stage, at which curative treatment was no longer viable. A clear guideline for choosing an alternative antipsychotic agent is currently lacking, but an antipsychotic with low alfa-adrenergic affinity seems preferable. To prevent erectile disfunction following priapism, awareness of its severity is essential, for both doctor and patient.

Drug rediscovery in gastroenterology: from off-label to on-label use of thioguanine in inflammatory bowel disease

Drug rediscovery refers to the principle of using 'old' drugs outside the indications mentioned in the summary of product characteristics. In the past decades, several drugs were rediscovered in a wide variety of medical fields. One of the most recent examples is the unconditional registration of thioguanine (TG), a thiopurine derivative, in patients with inflammatory bowel disease in the Netherlands. In this paper, we aim to visualise potential hurdles that hamper drug rediscovery in general, emphasise the global need for optimal use and development of potentially useful drugs, and provide an overview of the registration process for TG in the Netherlands. With this summary, we aim to guide drug rediscovery trajectories in the near future.

A three-dimensional analysis of cranial nerve development in human embryos

To increase our understanding of the etiology of specific neurological disorders (e.g., Duane syndrome, glossoptosis in Pierre Robin sequence), proper knowledge of anatomy and embryology of cranial nerves is necessary. We investigated cranial nerve development, studied histological sections of human embryos, and quantitatively analyzed the 3D reconstructions. A total of 28 sectioned and histologically stained human embryos (Carnegie stage [CS] 10 to 23 [21–60 days of development]) were completely digitalized by manual annotation using Amira software. Two specimens per stage were analyzed. Moreover, quantitative volume measurements were performed to assess relative growth of the cranial nerves. A chronologic overview of the morphologic development of each of the 12 cranial nerves, from neural tube to target organ, was provided. Most cranial nerves start developing at CS 12 to 13 (26–32 days of development) and will reach their target organ in stage 17 to 18 (41–46 days). In comparison to the rest of the developing brain, a trend could be identified in which relative growth of the cranial nerves increases at early stages, peaks at CS 17 and slowly decreases afterwards. The development of cranial nerves in human embryos is presented in a comprehensive 3D fashion. An interactive 3D‐PDF is provided to illuminate the development of the cranial nerves in human embryos for educational purposes. This is the first time that volume measurements of cranial nerves in the human embryonic period have been presented.

Systematic review with meta-analysis: SARS-CoV-2 stool testing and the potential for faecal-oral transmission

BACKGROUND

Since the start of the COVID-19 pandemic, there have been many scientific reports regarding gastrointestinal manifestations. Several reports indicate the possibility of viral shedding via faeces and the possibility of faecal-oral transmission.

AIMS

To critically assess the clinical relevance of testing stool samples and anal swabs and provide an overview of the potential faecal-oral transmission of SARS-CoV-2.

METHODS

A systematic literature search with MeSH terms was performed, scrutinising the Embase database, Google scholar, MEDLINE database through PubMed and The Cochrane Library, including articles from December 2019 until July 7 2020. Data were subsequently analysed with descriptive statistics.

RESULTS

Ninety-five studies were included in the qualitative analysis. 934/2149 (43%) patients tested positive for SARS-CoV-2 in stool samples or anal swabs, with positive test results up to 70 days after symptom onset. A meta-analysis executed with studies of at least 10 patients revealed a pooled positive proportion of 51.8% (95% CI 43.8 - 59.7%). Positive faecal samples of 282/443 patients (64%) remained positive for SARS-CoV-2 for a mean of 12.5 days, up to 33 days maximum, after respiratory samples became negative for SARS-CoV-2. Viable SARS-CoV-2 was found in 6/17 (35%) patients in whom this was specifically investigated.

CONCLUSIONS

Viral shedding of SARS-CoV-2 in stool samples occurs in a substantial proportion of patients, making faecal-oral transmission plausible. Furthermore, detection in stool samples or anal swabs can persist long after negative respiratory testing. Therefore, stool sample or anal swab testing should be (re)considered in relation to decisions for isolating or discharging a patient.

Systematic review with meta-analysis: risk factors for thiopurine-induced leukopenia in IBD

BACKGROUND

Thiopurine-induced leukopenia, a frequently observed and potentially life-threatening adverse event, complicates the clinical management of IBD patients.

AIM

To assess risk factors for thiopurine-induced leukopenia in IBD.

METHODS

MEDLINE, EMBASE, BIOSIS and Cochrane library were searched for studies reporting at least one risk factor for thiopurine-induced leukopenia. Pooled odds ratio (OR) was calculated for each potential risk factor using a random effects model. Studies that were not eligible for meta-analysis were described qualitatively.

RESULTS

Seventy articles were included, 34 (11 229 patients) were included in meta-analyses. A significantly higher thiopurine-induced leukopenia risk was found for TPMT (OR 3.9, 95% [CI] 2.5-6.1) and for NUDT15 R139C (OR 6.9, 95% CI 5.2-9.1), G52A (OR 3.2, 95% CI 1.3-7.9) and 36_37ins/delGGAGTC variant carriers (OR 5.6, 95% CI 2.8-11.4). A potential association between high 6-thioguanine nucleotides (6-TGN) or 6-methylmercaptopurine (6-MMP) levels and leukopenia was observed, since most studies reported higher metabolite levels in leukopenic patients (6-TGN: 204-308 (Lennard method) and 397 (Dervieux method), 6-MMP: 4020-10 450 pmol/8 x 10⁸ RBC) compared to controls (6-TGN: 170-212 (Lennard method) and 269 (Dervieux method), 6-MMP: 1025-4550 pmol/8 x 10⁸ RBC).

CONCLUSIONS

TPMT and NUDT15 variants predict thiopurine-induced leukopenia. High 6-TGN and 6-MMP levels might induce leukopenia, although exact cut-off values remain unclear. Potential preventive measures to reduce the risk of thiopurine-induced leukopenia include pre-treatment TPMT and NUDT15 genotyping. Routine thiopurine metabolite measurement might be efficient, yet cut-off levels must be validated in advance.

Clinical Course of Nodular Regenerative Hyperplasia in Thiopurine Treated Inflammatory Bowel Disease Patients

Nodular regenerative hyperplasia (NRH) is a poorly understood liver condition, which is increasingly recognized in thiopurine-treated patients with inflammatory bowel disease (IBD).¹ It is difficult to establish an optimal approach to NRH patients, because its manifestations are highly variable (from asymptomatic to symptoms of noncirrhotic portal hypertension [NCPH]) and the prognosis is unknown.² The aim of this study was to identify NRH cases in IBD patients treated with azathioprine, mercaptopurine, and/or thioguanine, and to describe its clinical course.

Oral cholera vaccination promotes homing of IgA+ memory B cells to the large intestine and the respiratory tract

Oral cholera vaccination is used to induce immune responses in the intestines to protect against cholera infection. However, oral vaccination may also affect immune responses in other mucosal tissues. To study this, tissue-specific homing potential and kinetics of B-cell responses were characterized after oral cholera vaccination. Healthy adult volunteers received two doses of Dukoral® and blood, saliva, nasal wash, and fecal samples were collected over time to detect vaccine-specific antibodies. Additionally, homing potential of lymphocytes to small intestine, colon, airways, skin, and periphery was measured by expression of Integrin β1 and β7, CCR9, CCR10, CCR7, and CLA. After vaccination, antibody responses to cholera toxin B (CTB) and Dukoral® were detected in serum and nasal wash. CTB-specific memory B cells in peripheral blood and tissue homing profiles of memory B cells peaked at day 18. IgA⁺ memory B cells expressed markers that enable homing to the airways and colon, while IgA^- memory B cells primarily expressed small-intestine-homing markers. These data show that oral cholera vaccination has a differential effect on immune responses in various mucosal sites, including the respiratory tract.

Methotrexate and Thioguanine Rescue Therapy for Conventional Thiopurine Failing Ulcerative Colitis Patients: A Multi-center Database Study on Tolerability and Effectiveness

BACKGROUND

Patients with active ulcerative colitis (UC) failing conventional therapies are in need of rescue strategies. Due to the fact that accepted step-up therapy with biologicals is expensive and sometimes unavailable, alternative therapies are warranted. Methotrexate (MTX) and thioguanine (TG) have both been suggested as alternative maintenance strategies in conventional thiopurine failing UC patients. In this multicenter database study, we compared safety and effectiveness (drug-survival) of MTX and TG in UC patients.

METHODS

We collected data from the Parelsnoer database, a prospective Dutch national database consisting of inflammatory bowel disease patients from all university hospitals in The Netherlands. Additional data were collected from detailed chart review.

RESULTS

In total, 99 UC patients were included, of which 48 used TG, 43 used MTX, and 8 patients had a history of both TG and MTX use. In 12% of the patients, biological therapy had failed. Roughly 70% of the patients in both groups were able to continue therapy for over 1 year. Adverse events were noted in 33% of all the patients and were mainly elevated liver enzymes or gastrointestinal complaints. Twenty-eight patients (28%) continued therapy (15 TG, 13 MTX) without the need of escalation therapy (eg, corticosteroids, biologicals, or surgery). Drug survival curves of both drugs were comparable, just as the number of patients with sustained clinical benefit of therapy (P > 0.05).

CONCLUSION

Both MTX and TG may be used and maintained as rescue therapy with sustained clinical benefit in one-third of the UC patients failing conventional therapies.

High inter-individual variability of serum xanthine oxidoreductase activity in IBD patients

OBJECTIVES

Thiopurines play an essential role in the management of inflammatory bowel diseases (IBD, i.e. Crohn's disease and ulcerative colitis). Over the past decade, several strategies to optimize treatment with thiopurines have been evaluated, including co-administration of allopurinol, a xanthine-oxidoreductase (XO) inhibitor, to low-dose thiopurine therapy. We aimed to assess the inter-individual variability of XO-activity between IBD-patients.

METHODS

We assessed XO activity in serum of IBD-patients of two medical centers in The Netherlands using the Amplex® Red Xanthine/Xanthine Oxidase Assay Kit, which measures the superoxide formation in a coupled reaction to the red-fluorescent oxidation product, resofurine.

RESULTS

We observed a high inter-individual variability of XO-activity in 119 patients, with a median activity of 16 µU/ml/hour (range 1-85 µU/ml/hour). The XO-activity was influenced by gender (male 19.5 vs. female 14.0 µU/ml/hour, p < 0.01), patient's age (Pearson's correlation r = 0.21, p = 0.02) and duration of IBD (r = 0.23, p = 0.01). The XO activity was not affected by the type of IBD, smoking status, body mass index or (type of) thiopurine use (p > 0.05).

CONCLUSIONS

There is a high inter-individual variability of XO-activity in IBD-patients; XO-activity is positively associated with male gender and patient's age.

Thiopurines in Inflammatory Bowel Disease: New Findings and Perspectives

Thiopurines, available as azathioprine, mercaptopurine, and thioguanine, are immunomodulating agents primarily used to maintain corticosteroid-free remission in patients with inflammatory bowel disease. To provide a state-of-the-art overview of thiopurine treatment in inflammatory bowel disease, this clinical review critically summarises the available literature, as assessed by several experts in the field of thiopurine treatment and research in inflammatory bowel disease.

Transient elastography to assess liver stiffness in patients with inflammatory bowel disease

BACKGROUND

Liver injury during inflammatory bowel disease (IBD) is primarily diagnosed by liver biopsy, which has a small but serious risk of severe complications. The aim of this study was to assess liver stiffness, and subsequently the prevalence and associations of liver fibrosis in IBD patients with thiopurine therapy and other clinical factors, by using transient elastography (TE).

METHODS

In this prospective, international two-center study, included IBD-patients underwent TE measurements. Laboratory results and medication reports, radiology results and historical liver biopsy results were extracted from the patient charts.

RESULTS

Transient elastography results of 168 patients were presented. Moderate and severe fibrosis were detected in 4% (7/168) and 1% (1/168) of the cohort, respectively. Factors contributing to lower liver stiffness were female gender and (historical) exposure to azathioprine. Further, there was a statistical trend towards lower liver stiffness in patients using thiopurines overall (4.7 vs. 5.2kPa, p=0.07). Liver stiffness correlated positively with waist circumference, liver enzyme tests, hemoglobin and 6-methylmercaptopurine concentration and negatively with platelet count.

CONCLUSION

Exposure to thiopurine therapy was not associated with higher liver stiffness, although no clinical difference in severity of fibrosis was detected. Further research should robustly determine the accuracy of TE as an evaluation of liver fibrosis in IBD patients.

6-methylmercaptopurine-induced leukocytopenia during thiopurine therapy in inflammatory bowel disease patients

BACKGROUND AND AIM

Thiopurines have a favorable benefit-risk ratio in the treatment of inflammatory bowel disease. A feared adverse event of thiopurine therapy is myelotoxicity, mostly occurring due to toxic concentrations of the pharmacologically active metabolites 6-thioguaninenucleotides. In oncology, myelosuppression has also been associated with elevated 6-methylmercaptopurine (6-MMP). In this case series, we provide a detailed overview of 6-MMP-induced myelotoxicity in inflammatory bowel disease patients.

METHODS

We retrospectively scrutinized pharmacological laboratory databases of five participating centers over a 5-year period. Patients with leukocytopenia at time of elevated 6-MMP levels (>5700 pmol/8 × 10⁸ red blood cells) were included for detailed chart review.

RESULTS

In this case series, we describe demographic, clinical, and pharmacological aspects of 24 cases of 6-MMP-induced myelotoxicity on weight-based thiopurine therapy with a median steady-state 6-MMP level of 14 500 pmol/8 × 10⁸ red blood cells (range 6600-48 000). All patients developed leukocytopenia (white blood cell count 2.7 ± 0.9 × 10⁹ /L) after a median period of 11 weeks after initiation of thiopurine therapy (interquartile range 6-46 weeks). Eighteen patients (75%) developed concurrent anemia (median hemoglobin concentration 6.9 × 10⁹ /L), and four patients developed concurrent thrombocytopenia (median platelet count 104 × 10⁹ /L). Leukocytopenia resolved in 20 patients (83%) within 4 weeks upon altered thiopurine treatment regimen, and white blood cell count was increasing, but not yet normalized, in the remaining four patients.

CONCLUSION

We observed that thiopurine-induced myelotoxicity also occurs because of (extremely) high 6-MMP concentrations in patients with a skewed thiopurine metabolism. Continued treatment with adapted thiopurine therapy was successful in almost all patients.

Nodular regenerative hyperplasia rarely leads to liver transplantation: A 20-year cohort study in all Dutch liver transplant units

BACKGROUND

Nodular regenerative hyperplasia is an uncommon liver condition associated with several autoimmune disorders and drugs. The clinical symptoms of nodular regenerative hyperplasia vary from asymptomatic to severe complications of portal hypertension (nodular regenerative hyperplasia-syndrome).

OBJECTIVE

The purpose of this study was to identify the prognosis and optimal management, as well as the role of liver transplantation, in nodular regenerative hyperplasia.

METHODS

The pathology databases of all three Dutch liver transplant units were retrospectively scrutinised for explanted livers diagnosed with nodular regenerative hyperplasia or without clear diagnosis. Pre- and post-transplantation clinical, biochemical, radiological and histological information was obtained from electronic and paper records.

RESULTS

In total, 1886 patients received a liver transplant. In 255 patients, nodular regenerative hyperplasia could not be excluded. After detailed chart review, the native livers of 11 patients (0.6%) (82% male, median age: 44 years) displayed nodular regenerative hyperplasia. Seven patients (64%) had underlying disorders or drug exposure which possibly caused nodular regenerative hyperplasia. Laboratory and imaging abnormalities were present in all patients but did not contribute to the diagnosis of nodular regenerative hyperplasia. Five-year survival was 73% (median follow-up: four years, range: 2-248 months).

CONCLUSION

Nodular regenerative hyperplasia is a rare finding in patients, predominantly young males, transplanted for end-stage liver disease with unknown aetiology. Nonetheless, liver transplantation may have an important role in end-stage nodular regenerative hyperplasia-syndrome.

How I treat my inflammatory bowel disease-patients with thiopurines?

Thiopurines are essential drugs to maintain remission in patients with inflammatory bowel disease (IBD). Thiopurines used in IBD are azathioprine (2.0-2.5 mg/kg), mercaptopurine (1.0-1.5 mg/kg) and thioguanine (0.2-0.3 mg/kg). However, mainly due to numerous adverse events associated with thiopurine use, almost 50% of the patients have to discontinue conventional thiopurine treatment. Extensive monitoring and the application of several treatment strategies, such as split-dose administration, co-administration with allopurinol or dose reduction/increase, may increase the chance of successful therapy. With this review, we provide practical information on how thiopurines are initiated and maintained in two thiopurine research centers in The Netherlands. We provide clinical information concerning safety issues, indications and management of therapy that may serve as a guide for the administration of thiopurines in IBD patients in daily practice.

Efficacy of thioguanine treatment in inflammatory bowel disease: A systematic review

AIM

To critically assess the available literature regarding the efficacy of thioguanine treatment in inflammatory bowel disease (IBD) patients, irrespective of the (hepato-) toxicity profile.

METHODS

A systematic literature search of the MEDLINE database using PubMed was performed using the keywords “thioguanine”, “6-TG”, “thioguanine”, “inflammatory bowel disease”, “IBD”, “Crohn’s disease”, “Ulcerative colitis” and “effectiveness” in order to identify relevant articles published in English starting from 2000. Reference lists of the included articles were cross-checked for missing articles. Reviewed manuscripts concerning the effectiveness of thioguanine treatment in IBD were reviewed by the authors and the data were extracted. Data were subsequently analyzed with descriptive statistics. Due to the lack of standardized outcomes, a formal meta-analysis was not performed.

RESULTS

A total of 11 applicable studies were found that involved the effectiveness of thioguanine therapy in IBD. Eight studies were conducted in a prospective manner, in the remaining three studies, data was collected retrospectively. In total, 353 IBD-patients (225 patients with Crohn’s disease, 119 with ulcerative colitis and nine with unclassified IBD) with prior azathioprine/mercaptopurine resistance and/or intolerance (n = 321) or de novo thioguanine administration (n = 32) were included for analysis, of which 228 (65%) had clinical improvement on thioguanine therapy, based on standard IBD questionnaires, biochemical parameters or global physician assessments. Short-term results were based on 268 treatment years (median follow-up 9 mo, range 3-22 mo) with a median daily dose of 20 mg (range 10-80 mg). Discontinuation, mostly due to adverse events, was reported in 72 patients (20%).

CONCLUSION

The efficacy of thioguanine therapy in IBD patients intolerant to conventional thiopurine therapy is observed in 65%, with short term adverse events in 20% of patients.

NUDT15: a novel player in thiopurine metabolism

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The diagnostic accuracy of serological tests for Lyme borreliosis in Europe: a systematic review and meta-analysis

Background

Interpretation of serological assays in Lyme borreliosis requires an understanding of the clinical indications and the limitations of the currently available tests. We therefore systematically reviewed the accuracy of serological tests for the diagnosis of Lyme borreliosis in Europe.

Methods

We searched EMBASE en MEDLINE and contacted experts. Studies evaluating the diagnostic accuracy of serological assays for Lyme borreliosis in Europe were eligible. Study selection and data-extraction were done by two authors independently. We assessed study quality using the QUADAS-2 checklist. We used a hierarchical summary ROC meta-regression method for the meta-analyses. Potential sources of heterogeneity were test-type, commercial or in-house, Ig-type, antigen type and study quality. These were added as covariates to the model, to assess their effect on test accuracy.

Results

Seventy-eight studies evaluating an Enzyme-Linked ImmunoSorbent assay (ELISA) or an immunoblot assay against a reference standard of clinical criteria were included. None of the studies had low risk of bias for all QUADAS-2 domains. Sensitivity was highly heterogeneous, with summary estimates: erythema migrans 50 % (95 % CI 40 % to 61 %); neuroborreliosis 77 % (95 % CI 67 % to 85 %); acrodermatitis chronica atrophicans 97 % (95 % CI 94 % to 99 %); unspecified Lyme borreliosis 73 % (95 % CI 53 % to 87 %). Specificity was around 95 % in studies with healthy controls, but around 80 % in cross-sectional studies. Two-tiered algorithms or antibody indices did not outperform single test approaches.

Conclusions

The observed heterogeneity and risk of bias complicate the extrapolation of our results to clinical practice. The usefulness of the serological tests for Lyme disease depends on the pre-test probability and subsequent predictive values in the setting where the tests are being used. Future diagnostic accuracy studies should be prospectively planned cross-sectional studies, done in settings where the test will be used in practice.

Disease activity assessment in IBD: clinical indices and biomarkers fail to predict endoscopic remission

BACKGROUND

In the current management paradigm, mucosal healing is preferred over clinical remission as a therapeutic end point in inflammatory bowel disease (IBD) because of the benefits engendered with respect to durability of remission. Colonoscopy, however, is not suitable for regular disease monitoring, and routine clinical assessment is often inaccurate with respect to endoscopic disease activity. The current investigation set out to characterize the relationship that exists between endoscopically determined IBD activity and clinical and biochemical measures of disease severity and to determine clinically useful thresholds for use in clinical practice.

METHODS

Patients attending for colonoscopy with known or suspected IBD were recruited. Clinical disease activity was recorded as per the Harvey-Bradshaw Index for Crohn's disease or the simple clinical colitis activity index for ulcerative colitis. Endoscopic activity was recorded using the simple endoscopic score for Crohn's disease or the modified Baron score for ulcerative colitis. Receiver operating characteristic analysis determined the predictive value and optimal predictive thresholds for clinical and biomarker data.

RESULTS

The Harvey-Bradshaw Index was not able to distinguish active from inactive Crohn's disease. The sensitivity, specificity, and positive and negative predictive values of simple clinical colitis activity index to detect endoscopic active disease were 43%, 96%, 94%, and 51%, respectively. Any elevation of C-reactive protein or fecal calprotectin was predictive of active mucosal disease, however, no lower threshold could be identified that predicted disease in remission.

CONCLUSIONS

C-reactive protein and fecal calprotectin are useful for the identification of endoscopically active IBD, but normal results do not confirm endoscopic remission.

Total soluble and endogenous secretory receptor for advanced glycation endproducts (RAGE) in IBD

BACKGROUND AND AIMS

Recruitment and activation of neutrophils, with release of specific proteins such as S100 proteins, is a feature of inflammatory bowel disease (IBD). Soluble forms of the receptor for advanced glycation endproducts (sRAGE), and variants such as endogenous secretory (esRAGE), can act as decoy receptors by binding ligands, including S100A12. The aims of this study were to determine total sRAGE and esRAGE concentrations in patients with IBD and correlate these with C-reactive protein (CRP), endoscopic scores and clinical disease activity scores.

METHODS

EDTA-plasma was collected from patients undergoing colonoscopy including those with Crohn's disease (CD: n=125), ulcerative colitis (UC: n=79) and control patients without endoscopic signs of inflammation (non-IBD: n=156). Concentrations of sRAGE and esRAGE were determined by enzyme-linked immunosorbent assay and plasma CRP concentrations measured. Standard clinical disease activity and endoscopic severity scores were defined for all subjects.

RESULTS

Plasma sRAGE concentrations were lower in UC (but not CD) than non-IBD subjects (p<0.01). Whilst sRAGE concentrations correlated negatively with endoscopic activity in UC (p<0.05), this was not seen in CD. In contrast, esRAGE correlated negatively with disease activity in both UC (p=0.002) and CD (p=0.0001). Furthermore, sRAGE and esRAGE concentrations correlated inversely with CRP values (p<0.0001).

CONCLUSIONS

Although total sRAGE varied with activity in UC, esRAGE concentrations correlated inversely with endoscopic disease activity and CRP levels in both UC and CD. Additional studies are required to further define the significance of sRAGE and esRAGE in IBD.

Granulocyte transfusions for pediatric patients and the establishment of national treatment guidelines and donor registry

G-CSF/dexamethasone stimulated donor derived granulocyte transfusion (GTX) has been shown in non-randomized studies to be a useful co-therapy in immune-compromised patients unresponsive to conventional antimicrobial treatments. Reports of GTX are however usually single institution adult experiences. Substantiated pediatric data, other than in neonates, is less common.

Ethnic differences in cigarette smoking among adolescents: a comparison of Jews and Arabs in Jerusalem

BACKGROUND

Prevention of cigarette smoking is an important issue in public health policy. Since most adult smokers began smoking in childhood, understanding behavorial factors associated with smoking initiation would contribute to smoking initiation programs. Health-related behavior may vary between different ethnic groups.

OBJECTIVES

To determine the prevalence of smoking among Jewish and Arab adolescents in Jerusalem, and whether there are differences in smoking initiation between the two ethnic groups.

METHODS

We carried out a cross-sectional survey of all students in the 6th to 11th grades (age range 11-17 years) of a Jewish school and an Arab school in the Jerusalem area, using an anonymous self-completion questionnaire. A total of 791 questionnaires was analyzed, 479 from the Jewish students and 312 from the Arab students.

RESULTS

The lowest prevalence of smoking was found among Arab female students and the highest among Jewish female students (9% vs. 41%, P < 0.001). The prevalence of smoking among Jewish and Arab males was similar. More Arab female students smoked than their mothers. Peer pressure seemed to be a more important factor among Jewish students.

CONCLUSIONS

This study demonstrated the presence of ethnic differences in smoking prevalence and the reasons for smoking among adolescents in Israel. These results suggest the need for specific smoking prevention policies for different ethnic groups.

[Circumcision from a historical perspective]

Male circumcision has been practiced by many tribes in different continents. The oldest image of a circumcision dates from 2300 BC and was found in Egypt. In the Jewish religion circumcision symbolizes the covenant between God and Abraham. Despite the fact that Jesus of Nazareth was circumcised, circumcision has never been part of Christianity. Circumcision is not mentioned in the Koran; the practice of circumcision in Islam is attributed to Abraham, who is considered by muslims to be one of the prophets. From the middle of the nineteenth century circumcision was performed for medical reasons. Throughout the centuries, from the time of the Bible, many methods for performing circumcision have been described, and a few to undo it by restoring the prepuce.

Extensive neuronal cell death following intracranial transection of the facial nerve in the adult rat

The aim of the present study is to examine the neuronal degeneration and the glial response following intracranial transection of the facial nerve close to the brainstem and furthermore to compare the results with a distal nerve injury. The facial nerve was cut either intracranially in the posterior cranial fossa or further distally, where it passes the parotid gland, in adult rats. Intracranial axotomy caused a massive loss of neuronal profiles. Only 26.8+/-11.3% of facial motor neuronal profiles were found ipsilateral to the nerve injury when compared to the contralateral side, following intracranial axotomy. This was statistically significant in comparison to the distal injury (72.4+/-9.5%), 4 weeks post-lesion. Reactive microglial cells expressed ED1 immunoreactivity following the intracranial axotomy but not following the distal nerve injury. In conclusion, there was a large discrepancy in neuronal degeneration as well as presence of phagocytic (ED1 positive) microglia between the two lesions. The intracranial lesion model used in the present study generates a massive neuronal cell death and should therefore be a useful tool for studies on proximal cranial nerve injuries and in particular mechanisms causing cell death, which may occur following, for example, head trauma.

Adhesion properties, intermediate filaments and malignant behaviour of head and neck squamous cell carcinoma cells in vitro

This study compared phenotype and behaviour of seven head and neck squamous cell carcinoma (HNSCC) cell lines and normal epithelial cells. Indications were found that in HNSCC cells: 1) loss of the cell-cell adhesion molecule E-cadherin was correlated with loss of epithelioid cell morphology but not with loss of cell-cell cohesion; 2) reduced expression of the cell-cell adhesion molecule desmoglein was unrelated to cell shape or motility; 3) high expression of the cell-substrate adhesion molecule alpha 6 beta 4, a receptor for laminin, corresponded with epithelioid colony formation while, in our adhesion assay, low expression of alpha 6 beta 4 paradoxically coincided with an increased adhesion to laminin; 4) presence of vimentin intermediate filaments coincided with loss of anchorage dependency. We propose that by simultaneous downregulation of E-cadherin, replacement of alpha 6 beta 4 by an aberrant laminin receptor and co-expression of vimentin a malignant phenotype arises of spindle-shaped, motile, anchorage-independent HNSCC cells with enhanced laminin-binding capacity.

Cigarette smoking habits among schoolchildren

STUDY OBJECTIVE

Cigarette smoking is a major preventable cause of morbidity and mortality worldwide. Most adult smokers start smoking regularly some time before 18 years of age. The aim of this study was to determine the age at which children begin cigarette smoking, to study the environmental factors that influence children to smoke, and to understand the reasons why children smoke. The results of this study may help lead to the development of more effective smoking prevention programs.

METHODS

We carried out a cross-sectional survey of all students in grades 6 to 11 (ages: 11 to 17 years) in two high schools in the Jerusalem area, using an anonymous self-completion questionnaire. The students were asked questions regarding the age at which they began smoking, initiation, their smoking habits, their reasons for smoking, and their views on children who smoke. In addition, they were asked about the smoking status of their parents, siblings, and friends. Finally they were asked about the health hazards of smoking.

RESULTS

Of the 847 students who answered the questionnaire, 35% stated that they had smoked at least once and 14% stated that they were currently smoking. The percentage of students who were currently smoking increased gradually with age to 36%. There was a sharp increase in experimental smoking after seventh grade (ages 12 to 13 years). Having a friend who smoked substantially increased the likelihood of smoking, whereas parental smoking or having a sibling who smoked did not increase the likelihood of smoking. The most common reason for starting to smoke was "to try something new" (55%). There was a significant difference between the views of students with different smoking statuses regarding children who smoke: nonsmoking children associated more negative characteristics to smoking. All of the children studied were well aware of the health hazards of cigarette smoking.

CONCLUSIONS

Smoking is highly prevalent among schoolchildren in Jerusalem. The increase in the rate of smoking at the age of 12 years indicates that smoking prevention programs need to be started at an earlier age. Peer pressure is a very strong stimulus for smoking in children. Since children are aware of the health hazards of smoking, prevention policy should be aimed more at associating smoking with negative images and addressing peer pressure.