Search for supersymmetry with gauge-mediated breaking in diphoton events at D0

We report the results of a search for supersymmetry (SUSY) with gauge-mediated breaking in the missing transverse energy distribution of inclusive diphoton events using 263 pb(-1) of data collected by the D0 experiment at the Fermilab Tevatron Collider in 2002-2004. No excess is observed above the background expected from standard model processes, and lower limits on the masses of the lightest neutralino and chargino of about 108 and 195 GeV, respectively, are set at the 95% confidence level. These are the most stringent limits to date for models with gauge-mediated SUSY breaking with a short-lived neutralino as the next-to-lightest SUSY particle.

Measurement of the B0s lifetime in the exclusive decay channel B0s-->J/psiphi

Using the exclusive decay B0s-->J/psi(mu+mu-)phi(K+K-), we report the most precise single measurement of the B0s lifetime. The data sample corresponds to an integrated luminosity of approximately 220 pb(-1) collected with the D0 detector at the Fermilab Tevatron Collider in 2002-2004. We reconstruct 337 signal candidates, from which we extract the B0s lifetime, tau(B0s)=1.444(+0.098)(-0.090)(stat)+/-0.020(sys) ps. We also report a measurement for the lifetime of the B0 meson using the exclusive decay B0-->J/psi(mu+mu-)K*0(892)(K+pi-). We reconstruct 1370 signal candidates, obtaining tau(B0)=1.473(+0.052)(-0.050)(stat)+/-0.023(sys) ps, and the ratio of lifetimes, tau(B0s)/tau(B0)=0.980(+0.076)(-0.071)(stat)+/-0.003(sys).

LIF receptor signaling modulates neural stem cell renewal

Activation of the leukemia inhibitory factor (LIF) receptor has been reported to promote gliogenesis and also to support neural stem cell (NSC) renewal. To investigate this paradox, we isolated NSCs and generated neurospheres from embryonic mice either wild-type, heterozygous, or homozygous null for LIF receptor (LIFR)-beta. Exogenous LIF abrogated neurosphere formation and promoted expression of GFAP by all cells in wild-type and heterozygous cultures. LIF also stimulated a twofold increase in the number of multipotential clones generated from these cultures in comparison with those pretreated with EGF and FGF-2 (E+F) alone. In contrast, the clonogenicity of low-density cultures of LIFR knockout cells was reduced in comparison with that of wild-type cells grown in E+F and was unaffected by LIF. Thus, although LIFR signaling is not necessary for NSC self-renewal, it enhances both the clonogenicity and the expression of GFAP by these multipotential cells.

Observation and properties of the X(3872) decaying to J/psipi(+)pi(-) in pp collisions at sqrt[s]=1.96 TeV

We report the observation of the X(3872) in the J/psipi(+)pi(-) channel, with J/psi decaying to mu(+)mu(-), in pp collisions at sqrt[s]=1.96 TeV. Using approximately 230 pb(-1) of data collected with the Run II D0 detector, we observe 522+/-100 X(3872) candidates. The mass difference between the X(3872) state and the J/psi is measured to be 774.9+/-3.1(stat)+/-3.0(syst) MeV/c(2). We have investigated the production and decay characteristics of the X(3872) and find them to be similar to those of the psi(2S) state.

Search for doubly charged higgs boson pair production in the decay to mu(+)mu(+)mu(-)mu(-) in pp collisions at sqrt[s]=1.96 TeV

A search for pair production of doubly charged Higgs bosons in the process pp -->H(++)H(--) -->mu(+)mu(+)mu(-)mu(-) is performed with the D0 run II detector at the Fermilab Tevatron. The analysis is based on a sample of inclusive dimuon data collected at an energy of sqrt[s]=1.96 TeV, corresponding to an integrated luminosity of 113 pb(-1). In the absence of a signal, 95% confidence level mass limits of M(H(+/-+/-)(L))>118.4 GeV/c(2) and M(H(+/-+/-)(R))>98.2 GeV/c(2) are set for left-handed and right-handed doubly charged Higgs bosons, respectively, assuming 100% branching into muon pairs.

Effect of comprehensive validation of the template isolation procedure on the reliability of bacteraemia detection by a 16S rRNA gene PCR

The influence of the DNA extraction method on the sensitivity and specificity of bacteraemia detection by a 16S rRNA gene PCR assay was investigated. The detection limit of the assay was 5 fg with purified DNA from Escherichia coli or Staphylococcus aureus, corresponding to one bacterial cell. However, with spiked blood samples, the detection limits were 10(4) and 10(6) CFU/mL, respectively. The sensitivity of the S. aureus assay was improved to the level of the E. coli test with the addition of proteinase K to the commercial DNA extraction kit protocol. Ten (16.6%) of 60 amplification reactions were positive with templates isolated from sterile blood, while PCR reagent controls were negative, thereby indicating contamination during the DNA extraction process. Blood samples were spiked with serial dilutions of E. coli and S. aureus cells, and six PCR results were obtained from three extractions for each blood sample. A classification threshold system was devised, based on the number of positive reactions for each sample. Samples were deemed positive if at least four positive reactions were recorded, making it possible to avoid false-positive results caused by contamination. These results indicate that a comprehensive validation procedure covering all aspects of the assay, including DNA extraction, can improve considerably the validity of PCR assays for bacteraemia, and is a prerequisite for the meaningful detection of bacteraemia by PCR in the clinical setting.

[Electronic distribution of patient records and images through PACS: implementation of data protection at the University Hospital in Freiburg]

In large installations of a Picture Archiving and Communication System (PACS), data protection becomes an issue. Above all, not every employee should have access to all data stored in the system. At the Freiburg University Hospital, we developed a concept of dynamic assignment of authorization, assuring that every physician is authorized to the data of all patients under his care. We describe the technical implementation of data protection developed for the integration of PACS and electronic patient records in Freiburg. The system was installed in January 2001 and the experience of its two years in operation is reported.

[Treatment of superficial thrombophlebitis]

Superficial thrombophlebitis is a frequently occurring disease which, because of risk factors, affects women to a greater extent than men. The presence of deep venous thrombosis should be excluded by imaging procedures. Heparin or low-molecular weight heparins are indicated for treatment, if deep venous thrombosis is present or threatening. In the acute stage non-steroidal antiinflammatory drugs can be taken orally in order to alleviate pain and inflammation. In the case of concomitant chronic venous insufficiency, edema protective drugs (e. g. preparations containing horse chestnut extract and flavonoids) can support the therapy. For the treatment of inflammatory conditions in relatively short superficial vein segments without involvement of the deep venous system, a limitation to topical treatment is possible. In addition to compression therapy, the application of creams or gels containing heparin or heparinoids are the usual treatment approach. The use of topical products containing mucopolysaccharide polysulfate (MPS) has been proven to be beneficial. The problem of providing evidence of the efficacy of topical products in the therapy for superficial thrombophlebitis under the current strict demands of our regulatory authorities and of developing new products under these conditions is discussed.

Diagnostic accuracy of dermoscopy

The accuracy of the dinical diagnosis of cutaneous melanoma with the unaided eye is only about 60%. Dermoscopy, a non-invasive, in vivo technique for the microscopic examination of pigmented skin lesions, has the potential to improve the diagnostic accuracy. Our objectives were to review previous publications, to compare the accuracy of melanoma diagnosis with and without dermoscopy, and to assess the influence of study characteristics on the diagnostic accuracy. We searched for publications between 1987 and 2000 and identified 27 studies eligible for meta-analysis. The diagnostic accuracy for melanoma was significantly higher with dermoscopy than without this technique (log odds ratio 4.0 [95% CI 3.0 to 5.1] versus 2.7 [1.9 to 3.4]; an improvement of 49%, p = 0.001). The diagnostic accuracy of dermoscopy significantly depended on the degree of experience of the examiners. Dermoscopy by untrained or less experienced examiners was no better than clinical inspection without dermoscopy. The diagnostic performance of dermoscopy improved when the diagnosis was made by a group of examiners in consensus and diminished as the prevalence of melanoma increased. A comparison of various diagnostic algorithms for dermoscopy showed no significant differences in their diagnostic performance. A thorough appraisal of the study characteristics showed that most of the studies were potentially influenced by verification bias. In conclusion, dermoscopy improves the diagnostic accuracy for melanoma in comparison with inspection by the unaided eye, but only for experienced examiners.

[Distant healing and diabetes mellitus. A pilot study]

BACKGROUND

The Institut für Grenzgebiete der Psychologie und Psychohygiene, Freiburg (IGPP) in cooperation with the Abteilung Naturheilkunde, University Hospital, Zürich investigated whether Distant Healing has a beneficial effect on patients with diabetes mellitus regarding the state of the disease and quality of life.

OBJECTIVE

The goal of the pilot study was to observe the progression of the disease with various medical and psychological measures and to explore which of them might be sensitive for measuring possible treatment effects.

PATIENTS AND METHODS

14 diabetic patients were observed for a period of 16 weeks. Within this time they underwent a treatment of 4 consecutive weeks (weeks 9-12) by 5 experienced and trustworthy healers each. Patients were informed about the duration of the treatment but not about the time point of its beginning. Patients and healers never met and there was no contact between researchers and patients during the study period.

RESULTS

With regard to medical parameters, reduction in fructosamine level was observed during the healing period, increasing fructosamine level after the end of the healing period. Sensitivity, measured only at the beginning and at the end of the study period, decreased significantly. The other parameters showed some significant changes but there was no correlation to the Distant Healing intervention. Regarding the psychological data, only improvements were observed.

CONCLUSIONS

The results indicate the possibility that a Distant Healing intervention could have certain effects on patients with diabetes mellitus.

Risks and benefits of sequential imaging of melanocytic skin lesions in patients with multiple atypical nevi

OBJECTIVE

To evaluate the utility of sequential imaging of melanocytic skin lesions.

DESIGN

With the use of a computerized test environment, digital images of 80 melanocytic skin lesions (including 10 early melanomas) were presented to 24 dermatologists with different levels of experience in 3 sessions. The 3 sessions were designed to simulate the decision-making process (1) without the possibility of follow-up, (2) with the possibility of follow-up, and (3) after presentation of follow-up images.

MAIN OUTCOME MEASURES

Diagnostic performance in terms of sensitivity, specificity, accuracy, treatment threshold, and utility.

RESULTS

The possibility of follow-up increased the treatment threshold in all groups of dermatologists compared with decision making without the possibility of follow-up. The increase of the treatment threshold was accompanied by a loss of sensitivity and a gain in specificity. The overall diagnostic accuracy remained unchanged. After presentation of follow-up images, the diagnostic accuracy improved significantly. The sensitivity improved for all readers, but the specificity improved only for the most experienced readers. The utility of sequential imaging depended on the compliance of patients with follow-up. Under the assumption that all patients are compliant with follow-up, the utility of sequential imaging was superior to decision making without follow-up over a broad range of benefit-risk ratios.

CONCLUSIONS

Sequential imaging of melanocytic skin lesions is a useful procedure for patients with multiple atypical nevi. Uncritical use of sequential imaging cannot be recommended, because the utility of this technique depends on the experience in the interpretation of follow-up images and on the patient's compliance with follow-up.

Hymenoptera-venom-induced upregulation of the basophil activation marker ecto-nucleotide pyrophosphatase/phosphodiesterase 3 in sensitized individuals

BACKGROUND

Bee and wasp venoms are potent allergens capable of inducing severe clinical reactions. To detect immediate-type hypersensitivity to these allergens, a rapid in vitro test was developed that relies on the upregulation of ecto-nucleotide pyrophosphatase/phosphodiesterase 3 (E-NPP3) on activated basophils.

METHODS

Blood basophils of 13 healthy donors and 22 patients allergic to bee or wasp venom were analyzed for E-NPP3 (CD203c) expression using monoclonal antibody 97A6. Basophils were analyzed by flow cytometry after activation with anti-IgE antibody or allergen. Venom-induced E-NPP3 upregulation on basophils was compared with diagnostic parameters, including skin tests and assessment of specific IgE. In selected samples, the increase in E-NPP3 expression on activated basophils was compared with histamine release and CD63 upregulation.

RESULTS

In 20/22 patients sensitized to wasp or bee venom, E-NPP3 expression on basophils was upregulated in response to activation by allergen or anti-IgE. The maximum increase in E-NPP3 expression (above ten times of baseline) was achieved after 15 min of stimulation with 1 microg/ml of allergen or anti-IgE antibody. Sensitized individuals who failed to upregulate E-NPP3 in response to IgE receptor cross-linking also failed to induce histamine release and CD63 upregulation.

CONCLUSIONS

Flow cytometric determination of hymenoptera-venom-induced upregulation of E-NPP3 is a novel in vitro test to identify sensitized individuals.

Molecular and immunological characterization of arginine kinase from the Indianmeal moth, Plodia interpunctella, a novel cross-reactive invertebrate pan-allergen

IgE recognition of indoor allergens represents a major cause of allergic asthma in atopic individuals. We found that 52 of 102 patients suffering from allergic symptoms indoors contained IgE Abs against allergens from the Indianmeal moth (Plodia interpunctella), a ubiquitous food pest. Using serum IgE from a moth-sensitized patient we screened an expression cDNA library constructed from P. interpunctella larvae. cDNAs coding for arginine kinase (EC 2.7.3.3), a 40-kDa enzyme commonly occurring in invertebrates that is involved in the storage of such high-energy phosphate bonds as phosphoarginine, were isolated. Recombinant moth arginine kinase, designated Plo i 1, was expressed in Escherichia coli as a histidine-tagged protein with enzymatic activity, and purified to homogeneity by nickel chelate affinity chromatography. Purified recombinant arginine kinase induced specific basophil histamine release and immediate as well as late-phase skin reactions. It reacted with serum IgE from 13 of the 52 (25%) moth-allergic patients and inhibited the binding of allergic patients' IgE to an immunologically related 40-kDa allergen present in house dust mite, cockroach, king prawn, lobster, and mussel. Our results indicate that arginine kinases represent a new class of cross-reactive invertebrate pan-allergens. Recombinant arginine kinase may be used to identify a group of polysensitized indoor allergic patients and for immunotherapy of these individuals.

[Distant healing and clinical research]

Distant healing is one of the most controversially discussed methods of complementary medicine. In the first section this paper outlines the history of spiritual healing and describes some possible definitions and different methods of spiritual healing. Based on a literature search in Medline, EMBASE, Current Contents, Allied and Complementary Medicine Database (AMED) as well as a manual tracking, current distant healing studies (excluding therapeutic touch studies) (n = 16) and some review articles (n = 6) are outlined in the second section. In addition, the randomized clinical double-blind studies (n = 12) are judged as to their formal quality by means of the Jadad Scale and the Internal Validity Scale (IV). Based on the controversially discussed study by Harris et al., some discussion points in the research field of spiritual healing are presented in the third section of this paper. From the evidence contained in the studies of this review article, no firm conclusions about the efficacy or inefficacy of healing can yet be made.

Treatment of focal hyperhidrosis with botulinum toxin type A: long-term follow-up in 61 patients

BACKGROUND

The blocking action of botulinum toxin type A (BTX-A) on cholinergically innervated sweat glands has been used successfully to treat patients with focal hyperhidrosis.

OBJECTIVES

To investigate the long-term efficacy and safety of intradermal injections of BTX-A.

METHODS

We performed an open-label study in 61 patients treated over a period of 3 years for axillary or palmar hyperhidrosis. A total dose of 400 mU BTX-A (Dysport) was injected into both axillae or 460 mU BTX-A (Dysport) into both palms. The injections were repeated after relapse. Objective quantification of sweat production was performed using digitized ninhydrin-stained sheets.

RESULTS

Four weeks after BTX-A treatment the median reduction in sweat production was 71% compared with baseline (P < 0.001) in the axillary group and 42% (P = 0.005) in the palmar group. Subjective assessment of sweat production by the patients using a visual analogue scale (0, no sweating; 100, the most severe sweating) showed a significant reduction in both the axillary (P < 0.001) and palmar groups (P < 0.001). Secondary disturbances due to focal hyperhidrosis interfering with daily activities were markedly improved in both groups. The median time interval between the sets of injections was 34 weeks for axillary hyperhidrosis and 25 weeks for palmar hyperhidrosis. The treatment of palmar hyperhidrosis was complicated by transient but not disabling weakness of the small hand muscles in nine of 21 patients.

CONCLUSIONS

Repeated intradermal injections of BTX-A in patients with axillary and palmar hyperhidrosis are as effective as first treatments.

Compliance with follow-up and prognosis among patients with thin melanomas

The aim of this study was to report on the compliance with follow-up among patients with thin melanomas. We also examined the prognosis of patients with recurrent disease and whether there were any differences in prognosis associated with the time between the last follow-up examination and the onset of recurrence. A retrospective analysis of the records of 513 consecutive patients (50.3% males, mean age: 52.8+/-16.9 years) with thin melanomas (<1.5 mm Breslow thickness) was carried out. The estimated cumulative proportion of patients who still continued their follow-up examinations 5 years after diagnosis of the primary tumour was 55.3% (95% Confidence Interval (CI): 50.4--60.2%). The mean annual drop-out rate was 11.2%. The drop-out rate was similar for males and females and was not influenced by the patients' age or the tumour thickness. Among 263 patients who continued follow-up, 50.2% (n=132) were not compliant with the time schedule. 20 patients presented with recurrent disease after a median of 35.9 months (25--75% percentiles: 16.7--46.5 months). Six patients who did not have a follow-up examination within 1 year before the onset of recurrence presented with more advanced disease and had a worse prognosis (median survival: 12.5 months, hazard ratio: 3.5, 95% CI: 1.1--17.1, P=0.04), than those patients, who had a recent follow-up examination before the onset of recurrence (n=14, median survival: 22.3+ months). In the majority of recurrent cases with good prognosis, metastatic disease was confined to the regional lymph nodes and the presumptive diagnosis of metastatic disease was either made by palpation or by sonography of the regional lymph nodes. The observed drop-out rate of patients during the first 5 years of follow-up is substantial and does not depend on the patients' age, sex or on the tumour thickness. Although the frequency of recurrences among patients with thin melanomas is low, regular follow-up examinations including physical examination, as well as palpation and sonography of the regional lymph nodes, are essential.

A comparison of machine learning methods for the diagnosis of pigmented skin lesions

We analyze the discriminatory power of k-nearest neighbors, logistic regression, artificial neural networks (ANNs), decision tress, and support vector machines (SVMs) on the task of classifying pigmented skin lesions as common nevi, dysplastic nevi, or melanoma. Three different classification tasks were used as benchmarks: the dichotomous problem of distinguishing common nevi from dysplastic nevi and melanoma, the dichotomous problem of distinguishing melanoma from common and dysplastic nevi, and the trichotomous problem of correctly distinguishing all three classes. Using ROC analysis to measure the discriminatory power of the methods shows that excellent results for specific classification problems in the domain of pigmented skin lesions can be achieved with machine-learning methods. On both dichotomous and trichotomous tasks, logistic regression, ANNs, and SVMs performed on about the same level, with k-nearest neighbors and decision trees performing worse.

A ten-year analysis of demographic trends for cutaneous melanoma: analysis of 2501 cases treated at the University Department of Dermatology in Vienna (1990-1999)

BACKGROUND

The aim of the study is to provide recent demographic data on cutaneous melanoma in Austria.

PATIENTS AND METHODS

Patients with primary cutaneous melanoma diagnosed between January 1, 1990 and December 31, 1999 were included in the analysis. Data were retrieved from the melanoma registry of the University Department of Dermatology in Vienna.

RESULTS

In the observation period, 2501 cutaneous melanomas were diagnosed in 2427 patients (mean age: 55.4 yrs; 51.2% females). A total of 267 (10.7%) cutaneous melanomas were in situ, and 2234 (89.3%) were invasive. The median invasion thickness according to Breslow for invasive melanomas was 0.98 mm (25%-75% percentiles: 0.55-2.00 mm). We observed a significant trend towards thicker tumors with increasing age (p < 0.001). In patients less than fifty years of age, a significantly higher Breslow thickness was observed in men than in women (0.90 mm versus 0.80 mm, p = 0.03). The median Breslow thickness of invasive melanoma decreased from 1.20 mm in 1990 to 0.92 mm in 1999 (p for trend, < 0.001). Compared to women, men had melanomas more frequently on the back (43.8% versus 24.4%, p < 0.001). In women, melanomas were more frequently found on the lower legs than in males (21.5% versus 6.7%, p < 0.001). In a multivariate model, invasion thickness according to Breslow was the single most important predictor of survival.

CONCLUSION

Our data confirm recent reports from other European countries with regard to the decline in tumor thickness of cutaneous melanoma. Our data also demonstrate a need for improving early diagnosis, particularly in certain subgroups of patients.

The dermatoscope: a potential source of nosocomial infection?

Dermatoscopes are directly placed on the skin of patients and therefore may harbour potentially pathogenic bacteria. In this study we assessed bacterial contamination of dermatoscopes during routine use and examined the effectiveness of isopropyl alcohol and disposable lens covers. Aerobic bacterial cultures were performed on randomly selected dermatoscopes after examination of 39 patients. In addition, bacterial contamination of dermatoscopes after cleaning with 70% isopropyl alcohol and after using a disposable transparent lens cover was tested. Bacteria such as Staphylococcus epidermidis, Micrococcus species and Corynebacterium species, which are usually present on the skin, were repeatedly identified. In addition, rare bacteria such as Moraxella species were found. Known nosocomial micro-organisms such as Staphylococcus aureus were recovered from hospitalized patients. Disinfection with 70% isopropyl alcohol and the use of a disposable lens cover significantly reduced the number of bacteria. Image quality was identical with and without the use of a transparent lens cover. Dermatoscopes harbour potential pathogens and may be a source of bacterial transmission. Isopropyl alcohol is an effective cleaning agent for dermatoscopes. Disposable lens covers completely prevented bacterial transmission and are therefore recommended for routine dermatoscopy, especially in hospitalized patients.