A full genome search in multiple sclerosis

The aetiology of multiple sclerosis (MS) is uncertain. There is strong circumstantial evidence to indicate it is an autoimmune complex trait. Risks for first degree relatives are increased some 20 fold over the general population. Twin studies have shown monozygotic concordance rates of 25-30% compared to 4% for dizygotic twins and siblings. Studies of adoptees and half sibs show that familial risk is determined by genes, but environmental factors strongly influence observed geographic differences. Studies of candidate genes have been largely unrewarding. We report a genome search using 257 microsatellite markers with average spacing of 15.2 cM in 100 sibling pairs (Table 1, data set 1 - DS1). A locus of lambda>3 was excluded from 88% of the genome. Five loci with maximum lod scores (MLS) of >1 were identified on chromosomes 2, 3, 5, 11 and X. Two additional data sets containing 44 (Table 1, DS2) and 78 sib pairs (Table 1, DS3) respectively, were used to further evaluate the HLA region on 6p21 and a locus on chromosome 5 with an MLS of 4.24. Markers within 6p21 gave MLS of 0.65 (non-significant, NS). However, D6S461, just outside the HLA region, showed significant evidence for linkage disequilibrium by the transmission disequilibrium test (TDT), in all three data sets (for DS1 chi2 = 10.8, adjusted P < 0.01)(DS2 and DS3 chi2 = 10.9, P < 0.0005), suggesting a modest susceptibility locus in this region. On chromosome 5p results from all three data sets (222 sib pairs) yielded a multipoint MLS of 1.6. The results support genetic epidemiological evidence that several genes interact epistatically to determine heritable susceptibility.

A population-based study of multiple sclerosis in twins

Results from studies of twin concordance in multiple sclerosis have not conclusively differentiated between environmental and genetic factors that determine susceptibility to the disease. Published studies that have been based on case finding by public appeal have been characterized by difficulties in ascertainment. The data reported here are from a large population-based study of multiple sclerosis in twins, in which ascertainment has been relatively unbiased and the cooperation of patients nearly complete. A total of 5463 patients attending 10 multiple sclerosis clinics across Canada were surveyed. Twenty-seven monozygotic and 43 dizygotic twin pairs were identified, and the diagnosis of multiple sclerosis was verified by examination and laboratory investigation. Seven of 27 monozygotic pairs (25.9 percent) and 1 of 43 dizygotic pairs (2.3 percent) were concordant for multiple sclerosis. The concordance rate for 4582 nontwin siblings of patients at two multiple sclerosis clinics was 1.9 percent, closely paralleling the concordance rate in dizygotic twins. To the extent that the difference in concordance rates between monozygotic and dizygotic twins indicates genetic susceptibility, the results of this study show a major genetic component in susceptibility to multiple sclerosis.

A population-based study of multiple sclerosis in twins: update

This study is a 7.5-year follow-up of a population-based series of twins with multiple sclerosis (MS) whose mean age now exceeds 50 years. The twin pairs were identified through the Canadian nationwide system of MS clinics and were drawn from a population of 5,463 patients. After 7.5 years, the monozygotic concordance rate increased from 25.9 to 30.8% and the dizygotic-like sex concordance rate from 2.4 to 4.7%. These results are very similar to those of other population-based studies and to our own modified replication twin data reported here. We interpret the data to mean that MS susceptibility is genetically influenced, and a single dominant or even a single recessive gene is unlikely to account for this effect. The difference in concordance rates suggests that at least two or more genes are operative. These data also have important implications for the nature of the environmental effect(s) in MS susceptibility. Most monozygotic twins are discordant even after a correction for age and magnetic resonance imaging findings. This unambiguously demonstrates the powerful effect of nonheritable factors.

A transplantable insulinoma in the rat

A transplantable insulinoma was developed in inbred albino rats of the NEDH strain. The original tumor, 1 cm in diameter, was removed from the pancreas of a male parabiont 566 days folowing 1000 rads (10J/kg) of total body x-irradiation. The time required for implanted fragments to grow to 0.5-1.5 cm in diameter decreased from 5-8 months in the first generation to 2-5 months in the seventh generation. Successful transplantation in male animals followed for 4 or more months after transplantation was significantly greater than in female animals followed for a similar period of time (96% versus 69%). Light and electron microscopy revealed that the tumors consisted predominantly of well-granulated beta cells. Ultrastructural studies also showed small numbers of D-cells. Tumor extracts contained an average of 223 units of immunoreactive insulin and 25.9 mug of immunoreactive somato-statin per gram wet weight of tissue. Tumors generally produced increasingly profound hypoglycemia within 2-4 months following transplantation, with plasma glucose levels frequently falling to 40 mg/100 ml or lower prior to death. Removal of tumors from chronically hypoglycemic animals resulted in transient rebound hyperglycemia with plasma glucose levels above 300mg/100 ml within the first 24 hr and a gradual decline to normal levels of 129 mg/100ml in 2-4 days. These observations correlated with findings of marked atropy and degranulation of the beta cells in the pancreata of tumor-bearing animals, and with gradual return of normal light microscopic morphology following tumor removal.

Multiple sclerosis in childhood: clinical profile in 125 patients

Multiple sclerosis (MS) has its usual onset in early adult life (average age of 30 years), but age at clinical onset varies considerably. The implications of the age of onset on the clinical presentation and course of MS are unclear. This population-based retrospective study presents data from a group of 125 patients with onset of MS before age 16 years and can thus be considered as representative of MS occurring in childhood. It demonstrates that childhood MS is more frequent in girls, that it very often has a relapsing-remitting course, that initial bouts usually involve afferent structures of the central nervous system, that recovery from these is often complete, and that the pace of the disease is slow.

Tenascin-C aptamers are generated using tumor cells and purified protein

Tenascin-C (TN-C) is an extracellular matrix protein that is overexpressed during tissue remodeling processes, including tumor growth. To identify an aptamer for testing as a tumor-selective ligand, SELEX (systematic evolution of ligands by exponential enrichment) procedures were performed using both TN-C and TN-C-expressing U251 glioblastoma cells. The different selection techniques yielded TN-C aptamers that are related in sequence. In addition, a crossover procedure that switched from tumor cell to purified protein selections was effective in isolating two high-affinity TN-C aptamers. When targeting tumor cells in vitro, the observed propensity of naive oligonucleotide pools to evolve TN-C aptamers may be due to the abundance of this protein. In vivo, TN-C abundance may also be well suited for aptamer accumulation in the tumor milieu. A size-minimized and nuclease-stabilized aptamer, TTA1, binds to the fibrinogen-like domain of TN-C with an equilibrium dissociation constant (K(d)) of 5 x 10(-9) m. At 13 kDa, this aptamer is intermediate in size between peptides and single chain antibody fragments, both of which are superior to antibodies for tumor targeting because of their smaller size. TTA1 defines a new class of ligands that are intended for targeted delivery of radioisotopes or chemical agents to diseased tissues.

Emergence of vancomycin-resistant enterococci in New York City

Enterococci, a common cause of nosocomial infection, are intrinsically resistant to most antimicrobials and readily acquire additional resistance. Vancomycin-resistant enterococci (VRE) have caused clusters of nosocomial infections since 1988. In April, 1991, the New York City Department of Health asked all city laboratories to submit suspected VRE isolates for confirmation. Clinical and epidemiological characteristics of the first 100 patients with VRE were identified, and antimicrobial susceptibility testing, restriction enzyme analysis, and DNA-DNA hybridisation with the vanA gene probe were done. From September, 1989, to October, 1991, 361 patients with VRE were identified at 38 hospitals. The number of hospitals reporting VRE increased from 1 in 1989 to 38 by October, 1991. 98% of 100 VRE infections were nosocomially acquired and 83% patients had received vancomycin and/or a cephalosporin in the 30 days before isolation of VRE. Of 23 isolates from 21 of the first 100 patients, 19 (83%) were resistant to all available antimicrobials. Four vanA probing patterns were noted, and restriction enzyme analysis of the 23 isolates revealed 14 strains. VRE have emerged rapidly in New York City. Molecular analyses suggest that a highly mobile genetic element--eg, a transposon--is responsible for the rapid spread of vancomycin resistance.

Structure of RNA and RNA binding site in tobacco mosaic virus from 4-A map calculated from X-ray fibre diagrams

The structure of tobacco mosaic virus has been solved to a resolution of 4 A using fibre diffraction methods. The general fold of the protein is clear, the conformation may be deduced in many places, and the conformation of the RNA and its interaction with the protein can be seen.

In vivo diagnosis of cervical intraepithelial neoplasia using 337-nm-excited laser-induced fluorescence

Laser-induced fluorescence at 337-nm excitation was used in vivo to differentiate neoplastic [cervical intraepithelial neoplasia (CIN)], nonneoplastic abnormal (inflammation and human papilloma viral infection), and normal cervical tissues. A colposcope (low-magnification microscope used to view the cervix with reflected light) was used to identify 66 normal and 49 abnormal (5 inflammation, 21 human papilloma virus infection, and 23 CIN) sites on the cervix in 28 patients. These sites were then interrogated spectroscopically. A two-stage algorithm was developed to diagnose CIN. The first stage differentiated histologically abnormal tissues from colposcopically normal tissues with a sensitivity, specificity, and positive predictive value of 92%, 90%, and 88%, respectively. The second stage differentiated preneoplastic and neoplastic tissues from nonneoplastic abnormal tissues with a sensitivity, specificity, and positive predictive value of 87%, 73%, and 74%, respectively. Spectroscopic differences were consistent with a decrease in the absolute contribution of collagen fluorescence, an increase in the absolute contribution of oxyhemoglobin attenuation, and an increase in the relative contribution of reduced nicotinamide dinucleotide phosphate [NAD(P)H] fluorescence as tissue progresses from normal to abnormal in the same patient. These results suggest that in vivo fluorescence spectroscopy of the cervix can be used to diagnose CIN at colposcopy.

Quality of life of stroke survivors

Adaptation to stroke requires complex, long-term change in stroke survivors' lives. This study aimed at identifying those factors that influence quality of life (QOL) of geriatric stroke survivors 1-3 years post-discharge. The objectives were: to describe the overall quality of life of stroke survivors; to examine the relationships between sociodemographic variables, neurological variables, functional status, social support, perceived health status, depression, and overall QOL; and to determine the best predictors of QOL. Data were collected on 50 stroke survivors using a cross-sectional design and standardized questionnaires, including the Quality of Life Index, the Functional Independence Measure, the Social Support Inventory for Stroke Survivors and the Centre for Epidemiologic Studies Depression Scale. The overall quality of life of the study participants was low. The most important predictors of QOL were depression, marital status, quality of social support, and functional status. Depression was the strongest predictor of QOL. By employing a multi-dimensional perspective, this study confirmed that adaptation to stroke involves much more than physical function. Thus, rehabilitation programs for this group would be more effective if they are based upon a holistic approach.

ICORG 10-14: NEOadjuvant trial in Adenocarcinoma of the oEsophagus and oesophagoGastric junction International Study (Neo-AEGIS)

BACKGROUND

Neoadjuvant therapy is increasingly the standard of care in the management of locally advanced adenocarcinoma of the oesophagus and junction (AEG). In randomised controlled trials (RCTs), the MAGIC regimen of pre- and postoperative chemotherapy, and the CROSS regimen of preoperative chemotherapy combined with radiation, were superior to surgery only in RCTs that included AEG but were not powered on this cohort. No completed RCT has directly compared neoadjuvant or perioperative chemotherapy and neoadjuvant chemoradiation. The Neo-AEGIS trial, uniquely powered on AEG, and including comprehensive modern staging, compares both these regimens.

METHODS

This open label, multicentre, phase III RCT randomises patients (cT2-3, N0-3, M0) in a 1:1 fashion to receive CROSS protocol (Carboplatin and Paclitaxel with concurrent radiotherapy, 41.4Gy/23Fr, over 5 weeks). The power calculation is a 10% difference in favour of CROSS, powered at 80%, two-sided alpha level of 0.05, requiring 540 patients to be evaluable, 594 to be recruited if a 10% dropout is included (297 in each group). The primary endpoint is overall survival, with a minimum 3-year follow up. Secondary endpoints include: disease free survival, recurrence rates, clinical and pathological response rates, toxicities of induction regimens, post-operative pathology and tumour regression grade, operative in-hospital complications, and health-related quality of life. The trial also affords opportunities for establishing a bio-resource of pre-treatment and resected tumour, and translational research.

DISCUSSION

This RCT directly compares two established treatment regimens, and addresses whether radiation therapy positively impacts on overall survival compared with a standard perioperative chemotherapy regimen Sponsor: Irish Clinical Research Group (ICORG).

TRIAL REGISTRATION

NCT01726452 . Protocol 10-14. Date of registration 06/11/2012.

Increasing incidence of adenocarcinoma of the lung

Review of the histology of 219 lung cancers initially diagnosed at Lutheran General Hospital, Park Ridge, Illinois, in 1963-1967 and 1974-1976, confirms the increasing incidence of adenocarcinoma. This is due to an increase of adenocarcinoma in men. In women, the incidence of adenocarcinoma was higher than squamous carcinoma in the earliest period (44% adeno, 18% squamous). The percentage of women with lung cancer has also significantly increased from 19% to 31%, which increases the overall incidence of adenocarcinoma of the lung. As the number of women with lung carcinoma has increased, there has been no change in the percentage of adenocarcinoma in women.

Emotional stress and the development of multiple sclerosis: case-control evidence of a relationship

One hundred multiple sclerosis (MS) patients were compared to hospital controls, for life stress prior to onset age in the MS patients and controls did not differ on: the happiness of their childhood environment; their pre-onset age reaction to life's problems (relaxed and taking things in stride/tense or easily upset); or on their tendency to seek professional help with an emotional problem. However significantly more MS patients than controls reported that they were under unusual stress in the 2 yr period prior to onset age; and the MS patients described a greater number of stressful life situations, or single events, than the controls.

Emotion regulation in mother-child narrative co-construction: associations with children's narratives and adaptation

The associations were studied between early mother-child co-construction of a separation-reunion narrative and children's concurrent and later (a) emotion narratives and (b) behavior problems. Fifty-one children and their mothers were observed during a co-construction task when the children were age 4 1/2. At ages 4 1/2 and 5 1/2, children's narratives were elicited using the MacArthur Story-Stem Battery (MSSB), and mothers completed the Child Behavior Checklist. Results showed that children who were more emotionally coherent during the co-constructions had MSSB narratives that were more coherent, had more prosocial themes, and had fewer aggressive themes at ages 4 1/2 and 5 1/2. Moreover, such children had fewer behavior problems at both ages. The relations between narrative processes and emotion regulation are discussed.

Self-reported depressive symptomatology, mood ratings, and treatment outcome in sleep disorders patients

Based on self-rating questionnaire evaluation of symptoms of major affective disorder, 67% of patients who presented to a major sleep disorders center reported an episode of depression within the previous 5 years, and 26% described themselves as depressed at presentation. Furthermore, patients with sleep apnea, narcolepsy, or sleep-related periodic leg movements all averaged high rates of self-reported depressive symptomatology, which suggests that sleep disorders should be considered in the differential diagnosis of affective disorders, and vice versa. Change scores on the Profile of Mood States were obtained for four subgroups of patients who were undergoing conventional treatment. Significant improvement in scores was observed in obstructive sleep apneics treated surgically and in patients with sleep-related periodic leg movements placed on clonazepam, but not in narcoleptics placed on a stimulant or in insomniacs with chronic use of sedative-hypnotic drugs who were withdrawn from sleep medications. Differential improvement in POMS scores after treatment for different sleep disorders could mean that the relationship to mood disturbance differs for different sleep disorders.

A WBAN System for Ambulatory Monitoring of Physical Activity and Health Status: Applications and Challenges

Recent technological advances in sensors, low-power integrated circuits, and wireless communications have enabled the design of low-cost, miniature, lightweight, intelligent physiological sensor platforms that can be seamlessly integrated into a body area network for health monitoring. Wireless body area networks (WBANs) promise unobtrusive ambulatory health monitoring for extended periods of time and near real-time updates of patients' medical records through the Internet. A number of innovative systems for health monitoring have recently been proposed. However, they typically rely on custom communication protocols and hardware designs, lacking generality and flexibility. The lack of standard platforms, system software support, and standards makes these systems expensive. Bulky sensors, high price, and frequent battery changes are all likely to limit user compliance. To address some of these challenges, we prototyped a WBAN utilizing a common off-the-shelf wireless sensor platform with a ZigBee-compliant radio interface and an ultra low-power microcontroller. The standard platform interfaces to custom sensor boards that are equipped with accelerometers for motion monitoring and a bioamplifier for electrocardiogram or electromyogram monitoring. Software modules for on-board processing, communication, and network synchronization have been developed using the TinyOS operating system. Although the initial WBAN prototype targets ambulatory monitoring of user activity, the developed sensors can easily be adapted to monitor other physiological parameters. In this paper, we discuss initial results, implementation challenges, and the need for standardization in this dynamic and promising research field.

Antiviral efficacy in vivo of the anti-human immunodeficiency virus bicyclam SDZ SID 791 (JM 3100), an inhibitor of infectious cell entry

SID 791, a bicyclam inhibiting human immunodeficiency virus (HIV) replication in vitro by blocking virus entry into cells, is an effective inhibitor of virus production and of depletion of human CD4+ T cells in HIV type 1-infected SCID-hu Thy/Liv mice. Steady levels of 100 ng of SID 791 or higher per ml in plasma resulted in statistically significant inhibition of p24 antigen formation. Daily injections of SID 791 caused a dose-dependent decrease in viremia, and this inhibition could be potentiated by coadministration of zidovudine or didanose. The present study suggests that SID 791 alone or in combination with licensed antiviral agents may decrease the virus load in HIV-infected patients and, by extension, that the infectious cell entry step is a valid target for antiviral chemotherapy of HIV disease. The SCID-hu Thy/Liv model in effect provides a rapid means of assessing the potential of compounds with novel modes of antiviral action, as well as the potential of antiviral drug combinations.

Extra intestinal influences on exhaled breath hydrogen measurements during the investigation of gastrointestinal disease

During the clinical investigation of patients with gastrointestinal disease by exhaled breath hydrogen measurement, the occurrence of inexplicable variations in recorded hydrogen values led to a search for extra intestinal factors which were capable of adversely influencing breath hydrogen concentration and impairing the diagnostic accuracy of the test. Serial breath samples were collected from normal subjects under a variety of conditions which might occur during routine clinical study, including, hyperventilation, exercise, cigarette smoking, and carbohydrate ingestion. Breath hydrogen concentrations were consistently reduced by hyperventilation (p less than 0.01) and exercise (p less than 0.05). Cigarette smoking, in contrast, caused a marked rise in measured breath hydrogen (p less than 0.01), as did oral carbohydrate (p less than 0.05). Prior bactericidal mouthwash abolished this carbohydrate associated rise, suggesting that the hydrogen was the result of fermentation by oropharyngeal bacteria. Because, in all instances, the changes in breath hydrogen were of sufficient magnitude to interfere with data interpretation, it is recommended that these factors are eliminated, whenever possible, from conditions of study.

Objective classification of motion- and direction-sensitive neurons in primary somatosensory cortex of awake monkeys

In order to classify movement-sensitive neurons in SI cortex, and to estimate their relative distribution, we have developed a new simple method for controlled motion of textured surfaces across the skin, as well as a set of objective criteria for determining direction selectivity. Moving stimuli were generated using 5 mm thick precision gear wheels, whose teeth formed a grafting. They were mounted on the shafts of low-torque potentiometers (to measure the speed and direction of movement) and rolled manually across the skin using the potentiometer shaft as an axle. As the grafting wheel was advanced, its ridges sequentially contacted a specific set of points on the skin, leaving gaps of defined spacing that were unstimulated. This stimulus was reproducible from trial to trial and produced little distention of the skin. Three objective criteria were used to categorize responses: the ratio of responses to motion in the most and least preferred directions [direction index (DI)], the difference between mean firing rates in the two directions divided by the average standard deviation [index of discriminability (delta'e)], and statistical tests. Neurons were classified as direction sensitive if DI greater than 35, delta's greater than or equal to 1.35 (equivalent to 75% correct discrimination by an unbiased observer), and firing rates in most- and least-preferred directions were significantly different (P less than 0.05). Good agreement was found between the three classification schemes. Recordings were made from 1,020 cortical neurons in the hand and forearm regions of primary somatosensory cortex (areas 3b, 1 and 2) of five macaque monkeys. Tangential motion across the skin was found to be an extremely effective stimulus for SI cortical neurons. Two hundred eighty six of 757 tactile neurons (38%) responded more vigorously to moving stimuli than to pressure or tapping the skin. One hundred twenty-one cells were tested with moving gratings and were classified according to their ability to differentiate movement in longitudinal and transverse directions. Responses to the moving gratings resembled those observed when stroking the skin with brushed, edges, or blunt probes. Three major types of firing patterns were found: motion sensitive, direction sensitive, and orientation sensitive. Motion-sensitive neurons (37%) responded to movement in both longitudinal and transverse directions with only slight difference in firing rates and interval distributions. Responses throughout the field were fairly uniform, and no clear point of maximum sensitivity was apparent. Direction-sensitive neurons (60%) displayed clear preferences for movement in one or more directions.4

Qualitative analysis of mental health service users' reported experiences of discrimination

OBJECTIVE

To better understand mental health service users' experiences of stigma and discrimination in different settings.

METHOD

An annual telephone survey of people with a mental health diagnosis conducted to evaluate the Time to Change antistigma campaign in England. Of 985 people who participated in 2013, 84 took part in a qualitative interview which was audio recorded. Of these, 50 interviews were transcribed and thematically analysed to explore accounts of discrimination. We analysed common types of behaviour; motivations ascribed to the discriminators; expectations of what fair treatment would have been; and the impact of discrimination on participants.

RESULTS

Discrimination was most common in five contexts: welfare benefits, mental health care, physical health care, family and friends. Participants often found it hard to assess whether a behaviour was discriminatory or not. Lack of support, whether by public services or by friends and family, was often experienced as discrimination, reflecting an expectation that positive behaviours and reasonable adjustments should be offered in response to mental health needs.

CONCLUSION

The impact of discrimination across different settings was often perceived by participants as aggravating their mental health, and there is thus a need to treat discrimination as a health issue, not just a social justice issue.

Emotional stress and coping in multiple sclerosis (MS) exacerbations

Ninety-five pairs of MS patients in exacerbation and remission were compared on emotional stress in the previous three months. Patients in exacerbation scored higher on emotional disturbance and intensity of stressful events than patients in remission, but lower on frequency of compensating uplifts. There was also a tendency for more patients in exacerbation than remission to favour emotion-focused coping techniques over problem-solving or social support. Whether patients building to an exacerbation over-react to various events or unresolved emotional stress precipitates exacerbations, MS patients might benefit from counselling in stress reduction techniques.

Propagation of fluorescent light

BACKGROUND AND OBJECTIVE

In general, the remitted fluorescence spectrum is affected by the scattering and absorption properties of tissue. Other important factors are boundary conditions, geometry of the tissue sample, and the quantum yield of tissue fluorophores. Each of these factors is examined through a series of Monte Carlo simulations.

STUDY DESIGN/MATERIALS AND METHODS

Monte Carlo modeling is used to simulate the propagation of excitation light and the resulting fluorescence. Remitted fluorescence is determined for semi-infinite single and multiple layer geometries and for cubic geometries representing small tissue samples. Monte Carlo results are compared to approximations obtained with a heuristic model.

RESULTS

Remitted fluorescence as a function of (1) the depth of fluorescence generation and (2) radial escape position is presented for semi-infinite single and multiple layer geometries. Fluorescence from a small tissue sample is simulated in terms of a cubic geometry, and losses from the sides and bottom are presented as a function of cube dimensions in terms of optical depth of the excitation wavelength. Monte Carlo results for a homogeneous semi-infinite layer are compared to a simple, fast heuristic model.

CONCLUSION

Both Monte Carlo simulations and the heuristic model clearly detail the volume of tissue interrogated by fluorescence. Since approximately 35-40% of the remitted fluorescence is due to photons originally directed away from the surface, distal layers affect the remitted fluorescence. Fluorescence spectra from small biopsy samples may not produce the correct line shape owing to wavelength dependent losses.