Activation of natural killer T cells potentiates or prevents experimental autoimmune encephalomyelitis

Natural killer (NK) T cells recognize lipid antigens in the context of the major histocompatibility complex (MHC) class 1-like molecule CD1 and rapidly secrete large amounts of the cytokines interferon (IFN)-gamma and interleukin (IL)-4 upon T cell receptor (TCR) engagement. We have asked whether NK T cell activation influences adaptive T cell responses to myelin antigens and their ability to cause experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis. While simultaneous activation of NK T cells with the glycolipid alpha-galactosylceramide (alpha-GalCer) and myelin-reactive T cells potentiates EAE in B10.PL mice, prior activation of NK T cells protects against disease. Exacerbation of EAE is mediated by an enhanced T helper type 1 (Th1) response to myelin basic protein and is lost in mice deficient in IFN-gamma. Protection is mediated by immune deviation of the anti-myelin basic protein (MBP) response and is dependent upon the secretion of IL-4. The modulatory effect of alpha-GalCer requires the CD1d antigen presentation pathway and is dependent upon the nature of the NK T cell response in B10.PL or C57BL/6 mice. Because CD1 molecules are nonpolymorphic and remarkably conserved among different species, modulation of NK T cell activation represents a target for intervention in T cell-mediated autoimmune diseases.

Positron emission tomography of cortical centers of tinnitus

Tinnitus is associated with a wide variety of disorders in the auditory system. Whether generated peripherally or centrally, tinnitus is believed to be associated with activity in specific cortical regions. The present study tested the hypothesis that these cortical centers subserve the generation, perception and processing of the tinnitus stimulus and that these processes are suppressed by lidocaine and masking. Positron emission tomography was used to map the tinnitus-specific central activity. By subtracting positron emission tomography images of regional cerebral blood flow distribution obtained during suppression of the tinnitus from positron emission tomography images obtained during the habitual tinnitus sensation, we were able to identify brain areas concerned with the cerebral representation of tinnitus. Increased neuronal activity caused by tinnitus occurred predominantly in the right hemisphere with significant foci in the middle frontal and middle temporal gyri, in addition to lateral and mesial posterior sites. The results are consistent with the hypothesis that the sensation of tinnitus is associated with activity in cortical regions functionally linked to subserve attention, emotion and memory. For the first time, the functional anatomy of conditions with and without the habitual tinnitus sensation was obtained and compared in the same subjects.

The effect of iron chelation on haemopoiesis in MDS patients with transfusional iron overload

Long-term follow-up data are presented on changes in peripheral blood counts and Hb requirements of 11 patients with myelodysplastic syndromes (MDS) during iron chelation treatment with desferrioxamine for up to 60 months. The erythroid marrow activity was indirectly evaluated by repeated determinations of the serum transferrin receptor concentration. The efficacy of iron chelation was evaluated by repeated quantitative determination of the liver iron concentration by magnetic resonance imaging. Reduction in the Hb requirement ( > or = 50%) was seen in 7/11 (64%) patients. Five patients (46%) became blood transfusion independent. Platelet counts increased in 7/11 (64%) patients and the neutrophil counts in 7/9 (78%) evaluable patients. All patients in whom iron chelation was highly effective showed improvement of erythropoietic output accompanied by an increase in the serum transferrin receptor concentration. It is concluded that reduction in cytopenia in MDS patients may be accomplished by treatment with desferrioxamine, if the iron chelation is efficient and the patients are treated for a sufficiently long period of time. Exactly how treatment with desferrioxamine works remains a challenge for further investigation.

Complex insomnia: insomnia and sleep-disordered breathing in a consecutive series of crime victims with nightmares and PTSD

BACKGROUND

Sleep disturbance in posttraumatic stress disorder is very common. However, no previous posttraumatic stress disorder studies systematically examined sleep breathing disturbances, which might influence nightmares, insomnia, and posttraumatic stress disorder symptoms.

METHODS

Forty-four consecutive crime victims with nightmares and insomnia underwent standard polysomnography coupled with a nasal pressure transducer to measure airflow limitation diagnostic of obstructive sleep apnea and upper airway resistance syndrome.

RESULTS

Forty of 44 participants tested positive on objective sleep studies based on conservative respiratory disturbance indices of more than 15 events per hour; 22 patients suffered from obstructive sleep apnea and 18 suffered from upper airway resistance syndrome.

CONCLUSIONS

In an uncontrolled study, insomnia and sleep-disordered breathing were extremely prevalent in this small and select sample of crime victims. Research is needed to study 1) prevalence of sleep-disordered breathing in other posttraumatic stress disorder populations using appropriate controls and nasal pressure transducers and 2) effects of sleep treatment on posttraumatic stress symptoms in trauma survivors with comorbid obstructive sleep apnea or upper airway resistance syndrome. In the interim, some posttraumatic stress disorder patients may benefit from sleep medicine evaluations.

Eosinophil and neutrophil activity in asthma in a one-year trial with inhaled budesonide. The impact of smoking

The object of this investigation was to study the long-term effects of antiasthma treatment on blood markers of inflammation and lung function in adult asthmatic subjects. For this purpose 85 allergic and nonallergic asthmatic subjects were randomized into three groups, which were given high-dose (1,600 micrograms/d) inhaled budesonide, low-dose (400 micrograms/d) inhaled budesonide, and oral theophylline (600 mg/d), respectively, and were followed for 11 mo with testing of lung function and blood sampling for the assay in serum of eosinophil cationic protein (ECP), eosinophil protein x/eosinophil derived neurotoxin (EPX/EDN) as eosinophil markers, and myeloperoxidase (MPO) and lactoferrin (LF) as neutrophil markers. Lung functions (FEV1% predicted, and histamine PC20) and the eosinophil markers ECP and EPX/EDN were improved and reduced, respectively, by budesonide in a dose-dependent and temporally parallel fashion. Theophylline did not alter lung functions but reduced ECP and EPX/EDN after prolonged treatment. The treatment efficacy of budesonide was attributed solely to an effect on nonsmoking asthmatic subjects, since neither lung functions nor eosinophil markers changed in smokers even with high-dose budesonide. MPO but not LF was reduced after several months of treatment in all three groups, but only in nonsmokers. We conclude that ECP and EPX/EDN may be used to monitor antiinflammatory treatment in asthmatic patients, and that smoking asthmatic subjects are resistant to inhaled corticosteroids.

Therapeutic experiences with 947 epileptic out-patients in oxcarbazepine treatment

Efficacy and tolerability of the new antiepileptic drug oxcarbazepine, was evaluated in a retrospective multicentre study. The records of all 947 epilepsy patients treated with oxcarbazepine in the eight participating centres from 1981 through 1990 were examined. The median daily dose of oxcarbazepine was 30 mg/kg in children, 18 mg/kg in adults, and 15 mg/kg in elderly patients, given b.i.d. or t.i.d. The mean plasma levels of the main active metabolite of oxcarbazepine was 88, 79, and 68 mumol/l in children, adults, and elderly, respectively. In patients shifted to oxcarbazepine treatment, seizure frequency was unchanged in 51-66%, 32-48% had a decrease, and 1-10% an increase in seizure frequency, considering the individual seizure types separately. Adverse events were reported in one third of patients, most frequently affecting the CNS (dizziness: 6%; sedation: 6%; fatigue: 6%). Rash was reported in 6% of patients, half of these patients had previously had an allergic reaction to carbamazepine. Hyponatremia was found in about a quarter of the patients from whom data were available. No congenital malformations were seen in nine live-born, first trimester oxcarbazepine-exposed children.

Guidelines for the use of EEG methodology in the diagnosis of epilepsy. International League Against Epilepsy: commission report. Commission on European Affairs: Subcommission on European Guidelines

The Commission of European Affairs of the International League Against Epilepsy published 'Appropriate Standards for Epilepsy Care Across Europe' which contained recommendations for the use of electroencephalography (EEG) in the diagnosis of epilepsy (Brodie et al. Epilepsia 1997; 38:1245). The need for a more specific basic document of EEG methodology was recognized and the Subcommission on European Affairs was asked to produce more detailed guidelines to be used across Europe recognizing the range of practices in EEG laboratories. There are many general guidelines published on EEG methodology but this document focuses on the diagnosis of epilepsy. Details from previously published guidelines are included in references and in an appendix. These guidelines are not meant to be used as minimal standards but recommendations that can be applied to all EEG laboratories despite variations in equipment.

Long-wavelength helimagnetic order and skyrmion lattice phase in Cu2OSeO3

We report a long-wavelength helimagnetic superstructure in bulk samples of the ferrimagnetic insulator Cu2OSeO3. The magnetic phase diagram associated with the helimagnetic modulation inferred from small-angle neutron scattering and magnetization measurements includes a skyrmion lattice phase and is strongly reminiscent of MnSi, FeGe, and Fe(1-x)Co(x)Si, i.e., binary isostructural siblings of Cu2OSeO3 that order helimagnetically. The temperature dependence of the specific heat of Cu2OSeO3 is characteristic of nearly critical spin fluctuations at the helimagnetic transition. This provides putative evidence for effective spin currents as the origin of enhancements of the magnetodielectric response instead of atomic displacements considered so far.

Risk factors among young women with endometrial cancer: a Danish case-control study

OBJECTIVE

This study was undertaken to identify and quantify risk factors for endometrial cancer among young women.

STUDY DESIGN

This case-control study included all Danish women <50 years old who had endometrial cancer diagnosed during the period 1987 to 1994. A total of 237 case patients and 538 population control subjects matched with the case patients for age and residence were included in the analysis.

RESULTS

Women with a family history of endometrial cancer had an odds ratio for endometrial cancer of 2.1 (95% confidence interval, 1.1-3.8)). Completion of 1 term pregnancy implied an odds ratio of 0.6 (95% confidence interval, 0.3-1.1). The risk of endometrial cancer decreased significantly with increasing age at first birth and with the number of induced abortions. Use of oral contraceptives for 1 to 5 years decreased the risk of endometrial cancer (odds ratio, 0.2; 95% confidence interval, 0.1-0.3). The odds ratio for endometrial cancer among women who received hormone replacement therapy for 1 to 5 years was 3.1 (95% confidence interval, 1.4-7.0). Body mass index was not demonstrated to be an independent risk factor in this study. The protective impacts of the different exposures (risk factors) can be expressed as etiologic fractions, which indicate how much each exposure reduces the occurrence of endometrial cancer compared with a situation without the existence of that particular exposure. These fractions were as follows: oral contraceptive use for > or =1 year, -45%; 2 term pregnancies, -88%; age > or =30 y when giving birth for the first time, -38%; and a history of incomplete pregnancy, -16%.

CONCLUSION

A number of risk factors for endometrial cancer are common to premenopausal and postmenopausal women: family history, reproductive history, hormone replacement therapy, and the use of oral contraceptives. Among young women reproductive variables imply the greatest prophylactic potential.

Tissue factor deficiency causes cardiac fibrosis and left ventricular dysfunction

Exposure of blood to tissue factor (TF) activates the extrinsic (TF:FVIIa) and intrinsic (FVIIIa:FIXa) pathways of coagulation. In this study, we found that mice expressing low levels of human TF ( approximately 1% of wild-type levels) in an mTF(-/-) background had significantly shorter lifespans than wild-type mice, in part, because of spontaneous fatal hemorrhages. All low-TF mice exhibited a selective heart defect that consisted of hemosiderin deposition and fibrosis. Direct intracardiac measurement demonstrated a 30% reduction (P < 0.001) in left ventricular function in 8-month-old low-TF mice compared with age-matched wild-type mice. Mice expressing low levels of murine FVII ( approximately 1% of wild-type levels) exhibited a similar pattern of hemosiderin deposition and fibrosis in their hearts. In contrast, FIX(-/-) mice, a model of hemophilia B, had normal hearts. Cardiac fibrosis in low-TF and low-FVII mice appears to be caused by hemorrhage from cardiac vessels due to impaired hemostasis. We propose that TF expression by cardiac myocytes provides a secondary hemostatic barrier to protect the heart from hemorrhage.

A comparison of monotherapy with lamotrigine or carbamazepine in patients with newly diagnosed partial epilepsy

Monotherapy with lamotrigine or carbamazepine was evaluated in a multicentre open trial of patients aged 2 years and above with newly diagnosed partial epilepsy. A total of 417 patients were randomised to treatment with lamotrigine, while 201 patients received carbamazepine. Following a dose escalation period of 6 weeks, maintenance therapy (Weeks 7-24) was adjusted according to response. Efficacy was similar with both treatments (65% with lamotrigine, 73% with carbamazepine, P=0.085). Efficacy was assessed by the proportion of patients seizure free during the last 16 weeks of treatment; all subjects who remained in the study for at least 18 weeks after the week 4 visit were included in the analysis. More patients receiving lamotrigine completed the study (81%), compared with those receiving carbamazepine (77%). This difference was primarily due to discontinuation as a result of adverse events, reported by 34 (8%) of those treated with lamotrigine but 26 (13%) of those treated with carbamazepine. The proportion of patients who experienced adverse events in the lamotrigine group was lower (218 patients, 52%) compared with the carbamazepine group (120 patients, 60%). The proportion of patients with adverse events considered to be drug related was lower in the lamotrigine group (132 patients, 32%) compared with the carbamazepine group (83 patients, 41%). Somnolence was the only adverse event reported at an incidence of greater than 5% and where there was a difference of 5% or more between treatment groups (4% lamotrigine, 11% carbamazepine patients). The small subsets of elderly patients (aged 65 years or over) and paediatric patients (aged 2-12 years) also showed better tolerability to lamotrigine than to carbamazepine. In conclusion, monotherapy with lamotrigine is as effective as carbamazepine in patients with newly diagnosed partial epilepsy. Patients were able to tolerate lamotrigine better than carbamazepine, so more patients receiving lamotrigine were able to remain on therapy.

Isolation and culture of human endometrial cells in a three-dimensional culture system

A cell culture system was established in which endometrial stromal cells were embedded in a collagen matrix and separated from the endometrial epithelium by basement membrane material (Matrigel). The epithelium, seeded on top of the collagen matrix, grew in a monolayer. The cultures were evaluated by light microscopy and transmission and scanning electron microscopy. Light and transmission electron microscopy indicated a polarized columnar epithelium in monolayer with basally positioned nuclei. Scanning electron microscopy revealed a confluent epithelium with an abundance of microvilli and cilia, as well as pinopodes on the apical surface. Immunohistochemical staining for cytokeratin confirmed the epithelial origin of the surface cells, and staining for human collagen IV demonstrated its presence underneath the epithelial cells. This culture system represents a three-dimensional system that imitates the normal endometrium.

Quantification of intracellular metabolic fluxes from fractional enrichment and 13C-13C coupling constraints on the isotopomer distribution in labeled biomass components

A method for the quantification of intracellular metabolic flux distributions from steady-state mass balance constraints and from the constraints posed by the measured 13C labeling state of biomass components is presented. Two-dimensional NMR spectroscopy is used to analyze the labeling state of cell protein hydrolysate and cell wall components. No separation of the biomass hydrolysate is required to measure the degree of 13C-13C coupling and the fractional 13C enrichment in various carbon atom positions. A mixture of [1-13C]glucose and uniformly labeled [13C6]glucose is applied to make fractional 13C enrichment data and measurements of the degree of 13C-13C coupling informative with respect to the intracellular flux distribution. Simulation models that calculate the complete isotopomer distribution in biomass components on the basis of isotopomer mapping matrices are used for the estimation of intracellular fluxes by least-squares minimization. The statistical quality of the estimated intracellular flux distributions is assessed by Monte Carlo methods. Principal component analysis is performed on the outcome of the Monte Carlo procedure to identify groups of fluxes that contribute major parts to the total variance in the multiple flux estimations. The methods described are applied to a steady-state culture of a glucoamylase-producing recombinant Aspergillus niger strain.

The effect of salmeterol on the early- and late-phase reaction to bronchial allergen and postchallenge variation in bronchial reactivity, blood eosinophils, serum eosinophil cationic protein, and serum eosinophil protein X

The late asthmatic response to bronchial allergen challenge and the associated increase in nonspecific bronchial reactivity provides a model for studying the acute inflammatory mechanisms in asthmatic airways. In 12 asthmatic patients (aged 22-37 years) with known dual reaction to allergen challenge, salmeterol 50 micrograms, 100 micrograms, or placebo was administered as a single dose 10 min before allergen challenge in a double-blind, randomized order on three different study days 2 weeks apart. The bronchial reactivity (BH) to histamine was measured the day before and 24 and 48 h after allergen challenge. Salmeterol significantly inhibited the early (P < 0.02) and the late (P < 0.05) asthmatic reactions. After placebo, mean BH was significantly increased above base line at 24 and 48 h (P < 0.02). After 50 and 100 micrograms salmeterol, BH was less than base line at 24 h and returned to prechallenge values at 48 h. Blood eosinophils increased significantly (P < 0.05) 24 and 48 h after allergen challenge, and no difference was found between treatments. After pretreatment with placebo, serum eosinophil cationic protein (s-ECP) and serum eosinophil protein X (s-EPX) increased significantly (P < 0.05) 24 and 48 h after allergen challenge. After treatment with salmeterol 50 micrograms, s-EPX, but not s-ECP, increased significantly 24 h after challenge, but was normal at 48 h. After salmeterol 100 micrograms, no change in s-EPX or s-ECP was found. The results showed that salmeterol eliminated the allergen-induced dual asthmatic reaction and gave protection against increased BH.(ABSTRACT TRUNCATED AT 250 WORDS)

Neoadjuvant therapy abolishes the functional benefits of a larger rectal remnant, as measured by magnetic resonance imaging after restorative rectal cancer surgery

BACKGROUND

The combination of advances in surgical technique and neoadjuvant therapy for rectal cancer has resulted in more patients undergoing sphincter-preserving surgery. Unfortunately, numerous patients subsequently experience bowel dysfunction, and may suffer from lifelong severe disability with major impact on their quality of life. The aim of the present study was to investigate whether the risk of severe LARS in patients was associated with the length of remnant rectum.

METHODS

A total of 125 patients who underwent sphincter-preserving surgery for rectal cancer were included. Postoperative bowel function was assessed using the low anterior resection syndrome (LARS) score a minimum of one year following surgery. The length of remnant rectum was measured on postoperative MRI of the pelvis and was correlated with the risk of having major LARS.

RESULTS

Overall, major LARS was observed in 38 per cent of patients. In the patients who underwent surgery alone, major LARS was reported by 27 per cent, and a larger remnant rectum was associated with a better functional outcome. In contrast, 80 per cent of patients who underwent combined preoperative chemoradiotherapy and surgery reported having major LARS. No association between the length of remnant rectum and the risk of major LARS was observed in patients treated with combined neoadjuvant therapy and surgery.

CONCLUSION

Both the length of remnant rectum and preoperative chemoradiotherapy had a major impact on the severity of bowel dysfunction after restorative rectal cancer surgery. No functional benefit from an irradiated rectal remnant was observed.

Role of cardiac myocyte tissue factor in heart hemostasis

BACKGROUND

The tissue-specific pattern of tissue factor (TF) expression suggests that it plays a major role in the hemostatic protection of specific organs, such as the heart and lung. In support of this notion, we found that mice expressing very low levels of TF exhibit hemostatic defects in the heart and lung. Hemosiderosis and fibrosis are observed in the hearts of all low TF mice as early as 3 months of age. In contrast, TF(+/-) mice expressing approximately 50% of wild-type levels of TF had no detectable hemostatic defects.

OBJECTIVE AND METHODS

The objective of this study was to determine the threshold of TF that is required to maintain hemostasis under normal and pathologic conditions, and to investigate the specific role of cardiac myocyte TF in heart hemostasis using mice with altered levels of TF expression in cardiac myocytes.

RESULTS

First, we found that mice with 20% of wild-type levels of TF activity in their hearts had hemosiderosis and fibrosis by 6 months of age. Secondly, mice with a selective deletion of the TF gene in cardiac myocytes had a mild hemostatic defect under normal conditions but exhibited a significant increase in hemosiderosis and fibrosis after challenge with isoproterenol. Finally, we showed that cardiac myocyte-specific overexpression of TF abolished hemosiderin deposition and fibrosis in the hearts of low TF mice.

CONCLUSIONS

Taken together, our results indicate that TF expression by cardiac myocytes is important to maintain heart hemostasis under normal and pathologic conditions.

Vasoactive intestinal polypeptide (VIP) provokes vaginal lubrication in normal women

The human vagina is known to be heavily innervated by vasoactive intestinal polypeptide (VIP) immunoreactive nerve fibres. In the present study we have examined the effect of VIP (900 pmol x kg-1 x h-1, IV during 30 min) on vaginal lubrication and blood flow in fourteen normal non-pregnant women. Vaginal blood flow was measured by the heat clearance technique and the vaginal lubrication quantified by the weight gain of preweighed filter papers placed on the surface of the vaginal wall for 30 min. Arterial blood pressure, pulse frequency and the concentration of VIP in peripheral blood were monitored. VIP (median concentrations of 200-300 pmol x l-1) induced a significant increase in vaginal blood flow accompanied by a 100% increase in vaginal lubrication (from 27 mg/cm2 to 53 mg/cm2). The VIP infusion lead to a significant increase in pulse frequency and a significant fall in diastolic arterial blood pressure. The findings suggest that VIP may participate in the control of the local physiological changes observed during sexual arousal: genital vasodilation and increase in vaginal lubrication.

On the association between valproate and polycystic ovary syndrome

Recent studies by Isojärvi et al. have raised the issue of an increased incidence of polycystic ovary syndrome (PCOS) in women with epilepsy treated with valproate (VPA) and have proposed replacement with lamotrigine (LTG). Polycystic ovaries (PCO) are a common finding, with a prevalence >20% in the general population, and are easily detected by pelvic or vaginal ultrasonography, whereas PCOS is comparatively rare: few women with PCO have fully developed PCOS, which includes hirsutism, acne, obesity, hypofertility. hyperandrogenemia, and menstrual disorders. From an extensive review of the current literature, it appears that there are no reliable data on the actual prevalence of PCOS in normal women and in women with epilepsy. The pathogenesis of PCO is multifactorial, including genetic predisposition and the intervention of environmental factors, among which weight gain and hyperinsulinism with insulin resistance may play a part. The roles of central (hypothalamic/pituitary), peripheral, and local ovarian factors are still debated. PCO and PCOS appear to be more frequent in women with epilepsy, but there are no reliable data showing a greater prevalence after VPA. The recent studies by Isojärvi et al. may have been biased by the retrospective selection of patients. To date, there is no reason to contraindicate the use of VPA in women with epilepsy. However, patients should be informed about the risk of weight gain and its consequences.

No influence of the antidepressant paroxetine on carbamazepine, valproate and phenytoin

A single-blind, placebo-controlled, cross-over trial investigating possible interactions between paroxetine, a serotonin re-uptake inhibitor, and carbamazepine (CBZ), valproate (VPA) and phenytoin (PHT) was carried out in 20 outpatients with epilepsy. Patients on long-term treatment with CBZ, VPA, or PHT were given a 7-day placebo treatment, followed by paroxetine co-treatment for 16 days. Side effects were infrequent and mild. Paroxetine caused no changes in the plasma concentrations and all values were within the recommended ranges. No changes in protein binding were found. Plasma concentrations of paroxetine at steady state (8-147 ng/ml) were in the normal range for a 30-mg daily dosing regimen. None of the patients experienced epileptic seizures during the study.

A genome-wide scan in affected sibling pairs with idiopathic recurrent miscarriage suggests genetic linkage

Previously, siblings of patients with idiopathic recurrent miscarriage (IRM) have been shown to have a higher risk of miscarriage. This study comprises two parts: (i) an epidemiological part, in which we introduce data on the frequency of miscarriage among 268 siblings of 244 patients with IRM and (ii) a genetic part presenting data from a genome-wide linkage study of 38 affected sibling pairs with IRM. All IRM patients (probands) had experienced three or more miscarriages and affected siblings two or more miscarriages. The sibling pairs were genotyped by the Affymetrix GeneChip 50K XbaI platform and non-parametric linkage analysis was performed via the software package Merlin. We find that siblings of IRM patients exhibit a higher frequency of miscarriage than population controls regardless of age at the time of pregnancy. We identify chromosomal regions with LOD scores between 2.5 and 3.0 in subgroups of affected sibling pairs. Maximum LOD scores were identified in four occurrences: for rs10514716 (3p14.2) when analyzing sister-pairs only; for rs10511668 (9p22.1) and rs341048 (11q13.4) when only analyzing families where the probands have had four or more miscarriages; and for rs10485275 (6q16.3) when analyzing one sibling pair from each family only. We identify no founder mutations. Concluding, our results imply that IRM patients and their siblings share factors which increase the risk of miscarriage. In this first genome-wide linkage study of affected sibling pairs with IRM, we identify regions on chromosomes 3, 6, 9 and 11 which warrant further investigation in order to elucidate their putative roles in the genesis of IRM.

Extracolonic findings at computed tomography colonography are a challenge

AIM

Our aim was to perform a prospective evaluation of the frequency and diagnostic consequences of extracolonic findings at multidetector array computed tomography colonography (MDCTC) in asymptomatic patients undergoing surveillance for former colorectal polyps or cancer.

PATIENTS AND METHODS

Seventy five consecutive patients undergoing surveillance for former colorectal cancer (CRC) or large bowel adenoma were examined with MDCTC. Two independent observers evaluated the images with regard to extracolonic findings. Patient records and radiological information systems were reviewed to determine the results and consequences of the workup derived from MDCTC.

RESULTS

Sixty five per cent (95% confidence interval (CI) 55-73%) of patients had extracolonic abnormalities and in 12% (CI 7-18%) of patients additional workup was indicated. Two patients (3% (CI 1-6%)) underwent surgery because of the findings (one) or because of complications of the workup (one).

CONCLUSION

MDCTC identifies a large number of extracolonic findings. Approximately 12% of asymptomatic patients undergo additional workup, of benefit to only a few. The high prevalence of extracolonic findings may make MDCTC a problematic colorectal screening tool for both ethical and economic reasons.

Vigabatrin: no microvacuoles in a human brain

Vigabatrin (gamma-vinyl-GABA) has been shown to be an effective antiepileptic drug. However, clinical investigations have been hampered by the finding of intramyelin edema (microvacuoles) in rats and dogs. In an autopsy study of a 38-year-old woman with astrocytoma, treated with vigabatrin 80 mg/kg body weight per day for over 6 months and 125 mg/kg body weight per day for the last 2 months as add-on therapy because of drug-resistant epilepsy, we did not find any microvacuoles in the brain. So far microvacuoles have never been observed in primates, warranting continued investigations of this promising antiepileptic drug.

Prospective study on the effect of smoking and nicotine substitution on leucocyte blood counts and relation between blood leucocytes and lung function

BACKGROUND

The influence of smoking and of nicotine substitution on the counts of total blood leucocytes and leucocyte subsets and the relations between the counts and lung function was investigated.

METHODS

The study was a combined cross sectional and prospective study of 298 smokers and 136 non-smokers. Forced expiratory volume in one second (FEV1) was measured in all participants at baseline and six months after quitting smoking in 160 ex-smokers (quitters) and 138 persons with smoking relapse. Blood samples were obtained from all participants at baseline and from 160 quitters and 30 continuing smokers two, six, 12, and 26 weeks after smoking cessation and from 92 quitters one year after the cessation of smoking.

RESULTS

Blood leucocyte counts and leucocyte subsets were all higher in smokers than in non-smokers. In cigarette smokers total leucocyte, neutrophil, and lymphocyte blood counts showed a dose dependent relationship with the daily cigarette consumption and pack years consumption. In smokers the neutrophil blood count was independently associated negatively with FEV1 residuals. After quitting smoking total leucocyte, neutrophil, and lymphocyte blood counts decreased during the first 26 weeks and after one year lymphocyte blood counts were higher than in non-smokers. In quitters substituted with nicotine chewing gum (2 mg) the accumulated number of pieces of chewing gum used in the 12 weeks had an inverse relationship with the decrease in the total lymphocyte blood count at 12 weeks after smoking cessation.

CONCLUSIONS

Leucocyte blood counts are raised in smokers and decrease after smoking cessation. Neutrophil blood counts had an inverse relationship with lung function and nicotine may increase lymphocyte blood counts in smokers.

Extent and completeness of mesorectal excision evaluated by postoperative magnetic resonance imaging

BACKGROUND

The major advance in rectal cancer management over the past 20 years has been the standardization of mesorectal excision. The aim of this study was to determine the prevalence and localization of inadvertent residual mesorectum detected on magnetic resonance imaging (MRI) after rectal cancer surgery.

METHODS

Postoperative T2-weighted MRI of the pelvis was performed on patients following mesorectal excision. A multidisciplinary team radiologist evaluated the images with regard to residual mesorectum and distal margin. Only mesorectum above the level of the anastomosis perpendicular to the bowel was regarded as inadvertent residual mesorectum after partial mesorectal excision. Histopathological records, standardized photographs and clinical records were assessed. The pathology and MRI findings were evaluated independently in a blinded fashion.

RESULTS

MRI-detected residual mesorectum was identified in 54 (39·7 per cent) of 136 patients. There was agreement with the pathology findings in 88 patients (64·7 per cent). Residual mesorectum was more frequent in patients treated with partial mesorectal excision (63 per cent) than those who had total mesorectal excision (36 per cent) or abdominoperineal resection (13 per cent) (P < 0·001). Pathology and MRI findings both showed that the distal resection margin after partial mesorectal excision was less than 5 cm in more than three-quarters of patients, and less than 3 cm in more than one-third.

CONCLUSION

Inadvertent residual mesorectum was commonly found on postoperative MRI, especially after partial mesorectal excision.