Beyond vandalism: Wikipedia trolls

Research on trolls is scarce, but their activities challenge online communities; one of the main challenges of the Wikipedia community is to fight against vandalism and trolls. This study identifies Wikipedia trolls’ behaviours and motivations, and compares and contrasts hackers with trolls; it extends our knowledge about this type of vandalism and concludes that Wikipedia trolls are one type of hacker. This study reports that boredom, attention seeking, and revenge motivate trolls; they regard Wikipedia as an entertainment venue, and find pleasure from causing damage to the community and other people. Findings also suggest that trolls’ behaviours are characterized as repetitive, intentional, and harmful actions that are undertaken in isolation and under hidden virtual identities, involving violations of Wikipedia policies, and consisting of destructive participation in the community.

Psychotic-like experiences are associated with suicidal feelings and deliberate self-harm behaviors in adolescents aged 12-15 years

OBJECTIVE

Psychotic disorders are a significant risk factor for suicide, especially among young people. Psychotic-like experiences (PLEs) in the general population may share an etiological background with psychotic disorders. Therefore, the present study examined the association between PLEs and risk of suicide in a community sample of adolescents.

METHOD

Psychotic-like experiences, suicidal feelings, and self-harm behaviors were studied using a self-report questionnaire administered to 5073 Japanese adolescents. Depression and anxiety were evaluated using the 12-item General Health Questionnaire (GHQ).

RESULTS

The presence of PLEs was significantly associated with suicidal feelings (OR = 3.1, 95% CI = 2.2-4.5) and deliberate self-harm behaviors (OR = 3.1, 95% CI = 2.0-4.8) after controlling for the effects of age, gender, GHQ-12 score, victimization, and substance use. Suicidal feelings and behaviors were more prevalent in subjects with a greater number of PLEs.

CONCLUSION

Psychotic-like experiences may increase the risk of suicidal problems among adolescents.

Patients achieving clearance of HCV with interferon therapy recover from decreased retinol-binding protein 4 levels

Retinol-binding protein 4 (RBP4) is a recently identified adipokine that is elevated in the blood in several insulin-resistant states. We investigated the association between plasma RBP4 and histological and biochemical characteristics of chronic hepatitis C (CHC), as well as changes in RBP4 levels following interferon therapy. Eighty-one patients with CHC infected with genotype 1 received treatment with peginterferon plus ribavirin. Histological data were available for 41 out of 81 patients before treatment, and the degree of fibrosis, inflammation and steatosis was assessed. Plasma levels of RBP4 were determined in serial samples (before, at the end of treatment, and at 6 months post-treatment). RBP4 levels were lower in CHC patients than in control subjects (34.6 +/- 12.3 microg/mL vs 46.2 +/- 10.5 microg/mL; P <or= 0.001). Higher RBP4 levels were linked to lower alanine aminotransferase (ALT) (P < 0.01), higher cholinesterase (P < 0.01), hyperlipidaemia (P < 0.01), hyperglycaemia (P < 0.05), and higher platelet (P < 0.01) count in CHC patients. Plasma RBP4 levels tended to decrease concomitantly with the grade of histological fibrosis, activity, and steatosis. RBP4 levels at baseline were not a predictor of the response to antiviral therapy in CHC patients. After peginterferon plus ribavirin therapy, only patients who had achieved clearance of hepatitis C virus had higher post-treatment RBP4 levels. This study suggests that an association between RBP4 levels and abnormal metabolic features, and that liver function may determine RBP4 levels in CHC patents. This is further supported by the observation that RBP4 levels increased significantly after treatment only in sustained virological response (SVR) patients and reached levels comparable to those of healthy subjects.

Online communities of practice typology revisited

This paper outlines a typology for online communities of practice. The typology is based on findings from observations of three online communities of practice, a content analysis of messages, and a review of the existing literature. The three examples of communities of practice are of electronic discussion lists that cover topics of interest to university webmasters, librarians, and educators. This work expands on a typology that consolidated prior research and focused on online communities of practice within organizational settings by extending it to be inclusive of open online communities of practice that are not constrained by any organizational context. Characterizing communities of practice in this manner enables various aspects of them to be analysed, which can illuminate ways to support the implementation of effective online communities of practice for specific purposes.

[Human parvovirus B19 infection in 15 adults--two-year Toho University Hospital study]

Human parvovirus B19 infection in adults features clinical symptoms and laboratory abnormal findings unlike those in children commonly associated with cheek rash. We diagnosed 15 adult cases based on the positive increase in anti-parvovirus B19 IgM antibody (8.89 +/- 7.86 mean +/- SD, enzyme immunoassay (EIA)). Antibody titer was measured in 78 patients clinically showing fever, edema, exanthema, arthralgia, and myalgia among 11,040 outpatients first visiting the hospital from January 2005 to December 2007. Based on clinical and laboratory findings for these 15 cases, we recommended that physicians taking anti-parvovirus B19 antibody blood samples note whether (1) the level of C reactive protein is negative or low and without leucocytosis; (2) a miliary rash is observed in short duration (rarely facial); (3) arthralgia and/or myalgia is present in the extremities (sometimes asymmetrical); (4) edema is present in the extremities, especially finger, ankle, or sole of the foot; (5) contact has been made with ill children; (6) flu-like symptoms occur such as fatigue, headache, or fever;and (7) normo- or hypocomplementemia and/or antinuclear antibody is positive. Patients who fulfill requirement (1) plus at least three of requirements (2) through (7) should have a blood sample taken. We retrospectively studied 78 cases using these requirements, finding their sensitivity to be 100% (15/15), specificity to be 88.9% (56/63), positive predictive value to be 68.1% (15/22) and negative predictive value to be 100% (56/56). These requirements are thus useful in selecting patients for measuring antibody titer and definitively diagnosing severe or persistent parvovirus B19 infection occationally observed in adults.

High prevalence of gastroesophageal reflux symptoms in patients with both acute and nonacute cough

Although there have been many studies that showed a close association between gastroesophageal reflux disease (GERD) symptoms and chronic cough, it has been unknown whether acute cough is also associated with GERD. The aim of this study was to evaluate the relationship between GERD and respiratory symptoms in general practice. 1725 consecutive patients who first attended our hospital were enrolled in the present study. They were asked to respond the F-scale questionnaire regardless of their chief complaints. Over all, 656 (38%) patients were diagnosed as GERD and 226 (13%) had respiratory symptoms. Patients with respiratory symptoms had GERD symptoms more frequently than patients without respiratory symptoms (p < 0.05). Forty-three (37%) of 115 patients with acute cough and 48 (43%) of 111 with nonacute cough had GERD symptoms, suggesting that development of GERD is not associated with the period of respiratory symptoms. Patients with respiratory symptoms are at a significantly increased risk of developing GERD. Whether or not treatment for GERD or respiratory diseases is useful for the prevention of respiratory symptoms and GERD, respectively, should not be driving management decisions in primary care.

An online listserv for nurse practitioners: a viable venue for continuous nursing professional development?

This study reports the results of a qualitative study involving a large and longstanding online nurse listserv in the United States. A sample of 27 critical care and advanced-practice nurse practitioners was interviewed using semi-structured individual interviews. This study found evidence that participation in an online listserv offers a viable avenue for the continuous professional development of nurses by providing nurses the opportunity to make more informed decisions about their professional practice and keeping abreast with up-to-date changes in their specialty areas when they shared knowledge with one another. Follow-up interviews with 10 nurses who frequently shared their knowledge revealed six motivators that helped promote knowledge sharing: (a) reciprocity, (b) collectivism, (c) personal gain, (d) respectful environment, (e) altruism, and (f) technology. Implications for sustaining knowledge sharing in an online listserv are discussed. The finding will inform educators and administrators who support continuing education and professional development of healthcare professionals.

Four new prenylated flavonoids and xanthones from the root bark of Artocarpus nobilis

Chemical investigation of the n-butanol extract from the methanol extract of the root bark of Artocarpus nobilis furnished four new prenylated flavonoids together with artonin E 2'-methylether (4), isoartonin E 2'-methylether (5), dihydroisoartonin E 2'-methylether (6), artonin V 2'-methylether (7), artobiloxanthone (1), artonin E (2) and cycloartobiloxanthone (3). All these compounds showed strong radical scavenging properties towards DPPH radical.

Salivary gland scintigraphy in gastro-esophageal reflux disease

Gastro-esophageal reflux disease (GERD) is associated with a decreased salivary flow as well as gastric acid production. This study therefore aimed to investigate functional disorders of salivary glands in patients with GERD.

METHODS

Thirty-one consecutive patients with GERD underwent salivary gland scintigraphy.

RESULTS

If the results defined the optimal cutoff point for determining the decreased salivary secretion as 51 % in parotid glands and 36 % in submandibular glands, a decreased salivary secretion of right parotid gland, left parotid gland, right submandibular gland, and left submandibular gland was found in 39 %, 32 %, 36 %, and 58 %, respectively. Overall, salivary function disorder of at least one major salivary gland was found in 24 patients (78 %) with GERD. There was no difference in the incidence of impaired salivary function between GERD patients with and without erosive esophagitis. Salivary gland function was more frequently diminished than expected in GERD. We concluded that the presence of impaired salivary gland function was considered to be one of risk factors for developing GERD symptoms.

The quality of evidence in knowledge management research: practitioner versus scholarly literature

The viability of KM partly rests on how researchers garner empirical support for their purported theories. One aspect of this would involve the evaluation of the evidence provided in KM research. This paper presents a comparative study of the evidence that is presented in scholarly and professional literature on KM. For this purpose, the paper introduces a typology of evidence to analyze the data obtained from the survey of the literature. The classification based on this typology reveals quantitative differences between the types of evidence put forth in the scholarly and practitioner literature. More interestingly, however, our analysis reveals differences in terms of the questions they ask, the perspective they adopt, and the methods they follow to convince others of the validity of their claims. We explain these differences in terms of the notions of `blackboxing' and `performance' borrowed from actor-network theory.

Importance of the intracrine metabolism of adrenal androgens in androgen-dependent prostate cancer

The metabolic pathways of androgens and processes by which androgens induce re-growth after androgen deprivation therapy in prostate cancer have not been fully elucidated. In this study, finasteride decreased PSA secretion in medium containing testosterone, androstenedione, androstenediol and dehydroepiandrosterone, whereas dihydrotestosterone (DHT)- and hydroxy-flutamide-induced PSA production was not inhibited by finasteride in LNCaP-FGC cells. The present data show that adrenal androgen precursors do not directly interact with androgen receptors (ARs) but are converted to DHT via the intraprostatic metabolic pathways, resulting in the induction of LNCaP activity. This is the first report confirming this mechanism experimentally and also suggest the use of combined therapies that target ARs and prevent the formation of DHT within prostate cancer cells to achieve optimal therapeutic efficacy.

(2-Nitro ethyl)phenyl and cyanophenyl glycosides from the fruits ofDiploclisia glaucescens

Chemical investigation of polar fractions of the methanol extract of the fruits of Diploclisia glaucescens of the family Menispermaceae furnished two new phenyl glycosides, 4-(2-nitroethyl)phenyl-beta-D-xylopyranosyl-(l approximately 6)-beta-D-glucopyranoside, and 4-cyanophenyl-beta-D-xylopyranosyl-(l approximately 6)-beta-D-glucopyranoside.

Absence of Bcl-2 and Fas/CD95/APO-1 predicts the response to immunotherapy in metastatic renal cell carcinoma

Immunotherapy is the only available treatment for metastatic renal cell cancer (RCC), but the response rate is only about 20% and the treatment is occasionally associated with severe adverse effects. Thus, the selection of patients with a high susceptibility to immunotherapy is needed; however, there is no promising molecular marker that can predict the response to immunotherapy for RCC. This study was carried out to elucidate the potential role of apoptosis-related molecules Bcl-2 and Fas, as well as apoptotic and proliferating indexes (AI, PI) as predictors of the susceptibility of metastatic RCC to immunotherapy. Immunohistochemical examination of tumour tissues from 40 patients with metastatic RCC undergoing postoperative immunotherapy after radical nephrectomy was performed. Patients with progressive disease (PD) after immunotherapy presented with decreased survival (P=0.006). Progressive disease correlated with higher PI in the primary lesion (P=0.0087). All primary tumours of CR or PR patients were negative for Bcl-2, whereas among NC+PD patients, 40.6% were positive for Bcl-2 (P=0.0373). Patients in whom the primary tumours were both Bcl-2- and Fas-negative showed significantly better responses to immunotherapy in comparison with the remaining group (P=0.0022). The Bcl-2 and Fas status of the primary lesion may become useful criteria for the selection of patients with metastatic RCC for immunotherapy.

Steroidal and Triterpenoidal saponins from the fruits of Diploclisia glaucescens

Chemical investigation of methanol extract of the fruits of Diploclisia glaucescens furnished 3-O-beta-D-glucopyranosyl-20-hydroxyecdysone, 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl]serjanic acid 28-O-beta-D-glucopyranosyl ester and 3-O-[beta-xylopyranosyl(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl]serjanic acid 28-O-beta-D-glucopyranosyl ester. The latter saponin was found to be a new natural product while the other two are reported for the first time from the family Menispermaceae.

Hydrogen and methane gases are frequently detected in the stomach

AIM: To investigate the incidence of bacterial overgrowth in the stomach by using a new endoscopic method in which intragastric hydrogen and methane gases are collected and analyzed.

METHODS: Studies were performed in 490 consecutive patients undergoing esophagogastroscopy. At endoscopy, we intubated the stomach without inflation by air, and 20 mL of intragastric gas was collected through the biopsy channel using a 30 mL syringe. Intragastric hydrogen and methane concentrations were immediately measured by gaschromatography. H pylori infection was also determined by serology.

RESULTS: Most of intragastric hydrogen and methane levels were less than 15 ppm (parts per million). The median hydrogen and methane values (interquartile range) were 3 (1-8) ppm and 2 (1-5) ppm, respectively. The high hydrogen and methane levels for indication of fermentation were decided if the patient had the values more than 90 percentile range in each sample. When a patient had a high level of hydrogen or methane in one or more samples, the patient was considered to have fermentation. The overall incidence of intragastric fermentation was 15.4% (73/473). Intragastric methane levels were higher in the postoperative group than in other groups. None of the mean hydrogen or methane values was related to H pylori infection.

CONCLUSION: Hydrogen and methane gases are more frequently detected in the stomach than expected, regardless of the presence of abdominal symptoms. Previous gastric surgery influences on the growth of methane-producing bacteria in the fasting stomach.