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Color and motion information are thought to be channeled through separate neural pathways, but it remains unclear whether and how these pathways interact to improve motion perception. In insects, such as Drosophila, it has long been believed that motion information is fed exclusively by one spectral class of photoreceptor, so-called R1 to R6 cells; whereas R7 and R8 photoreceptors, which exist in multiple spectral classes, subserve color vision. Here, we report that R7 and R8 also contribute to the motion pathway. By using electrophysiological, optical, and behavioral assays, we found that R7/R8 information converge with and shape the motion pathway output, explaining flies' broadly tuned optomotor behavior by its composite responses. Our results demonstrate that inputs from photoreceptors of different spectral sensitivities improve motion discrimination, increasing robustness of perception.

Glioblastoma multiforme (GBM) is a highly malignant brain tumor. The blood-brain barrier (BBB) provides a major obstacle to chemotherapy since therapeutic doses cannot be achieved by traditional drug delivery without severe systemic cytotoxic effects. Recently, microbubble (MB)-enhanced focused ultrasound (FUS) was shown to temporally and locally disrupt the BBB thereby enhancing drug delivery into brain tumors. Here we propose the concept of smart, multifunctional MBs capable of facilitating FUS-induced BBB disruption while serving as drug-carrying vehicles and protecting drugs from rapid degradation. The designed MBs had a high loading capacity (efficiency of 68.01 ± 4.35%) for 1,3-bis(2-chloroethyl)-1- nitrosourea (BCNU). When combined with FUS (1-MHz), these BCNU-MBs facilitated local BBB disruption and simultaneously released BCNU at the target site, thus increasing local BCNU deposition. Encapsulation of BCNU in MBs prolonged its circulatory half-life by 5-fold, and accumulation of BCNU in the liver was reduced 5-fold due to the slow reticuloendothelial system uptake of BCNU-MBs. In tumor-bearing animals, BCNU-MBs with FUS controlled tumor progression (915.3%-39.6%) and improved median survival (29 days-32.5 days). This study provides a new approach for designing multifunctional MBs to facilitate FUS-mediated chemotherapy for brain tumor treatment., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Detecting motion is a feature of all advanced visual systems [1], nowhere more so than in flying animals, like insects [2, 3]. In flies, an influential autocorrelation model for motion detection, the elementary motion detector circuit (EMD; [4, 5]), compares visual signals from neighboring photoreceptors to derive information on motion direction and velocity. This information is fed by two types of interneuron, L1 and L2, in the first optic neuropile, or lamina, to downstream local motion detectors in columns of the second neuropile, the medulla. Despite receiving carefully matched photoreceptor inputs, L1 and L2 drive distinct, separable pathways responding preferentially to moving "on" and "off" edges, respectively [6, 7]. Our serial electron microscopy (EM) identifies two types of transmedulla (Tm) target neurons, Tm1 and Tm2, that receive apparently matched synaptic inputs from L2. Tm2 neurons also receive inputs from two retinotopically posterior neighboring columns via L4, a third type of lamina neuron. Light microscopy reveals that the connections in these L2/L4/Tm2 circuits are highly determinate. Single-cell transcript profiling suggests that nicotinic acetylcholine receptors mediate transmission within the L2/L4/Tm2 circuits, whereas L1 is apparently glutamatergic. We propose that Tm2 integrates sign-conserving inputs from neighboring columns to mediate the detection of front-to-back motion generated during forward motion., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Aims: To determine the effect of methadone maintenance therapy (MMT) on mortality among injection drug users., Design: A cohort of prisoners with a history of injecting opiates who were followed after their release from prison in July 2007. Mortality between July 2007 and December 2008 was determined by linking the National Death Registry with the Methadone Maintenance Treatment (MMT) database., Setting: Taiwan., Participants: A total of 4357 amnestied prisoners with a history of opiate injection., Measurements: The total mortality rates (MR) among the cohort were calculated based on their person-time contribution to methadone attendance and re-incarceration during follow-up. We used survival methods with MMT and re-incarceration as time-varying covariates adjusted for length of follow-up in the community., Results: A total of 142 deaths occurred: 13 in the 1st week after release [MR = 13.7/100 person-years (pyrs)], which was greater than that in the next 4 weeks [MR = 3.2/100 pyrs, relative rate (RR) = 4.3, P < 0.001]. Overall, 1982 (46%) subjects enrolled in MMT; however, 1282 of them discontinued MMT after enrolling., Findings: The mortality among those who continued in MMT attendance was lower (MR = 0.24/100 pyrs) than those who never enrolled in MMT (MR = 2.6/100 pyrs) or those who enrolled but dropped out of MMT (MR = 7.0/100 pyrs) after adjusting for age, gender and human immunodeficiency virus status at amnesty (RR = 0.07)., Conclusions: In ex-prisoners in Taiwan with a history of opiate injecting, enrollment and continued participation in methadone maintenance treatment is associated with substantially lower mortality., (© 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.)

Here we report the development of a ternary version of the LexA::VP16/LexAop system in which the DNA-binding and trans-activating moieties are independently targeted using distinct promoters to achieve highly restricted, intersectional expression patterns. This Split LexA system can be concatenated with the Gal4/upstream activating sequence system to refine the expression patterns of existing Gal4 lines with minimal genetic manipulations.

Disruption of the blood-brain barrier (BBB) may be transiently achieved via high-frequency focused spherical ultrasound in the presence of microbubbles. In this experimental animal study, we sought to determine whether focal reversible opening of the BBB may be achieved using low-frequency (i.e., 20-30 kHz) planar ultrasonic waves. In the presence of microbubbles, we were able to obtain BBB opening using non-focused ultrasound irradiation with a frequency as low as 28 kHz. We also achieved a tight regulation of the ultrasound patterns by using a mechanical scanning device equipped with a pinhole. Histologic examination of the brains supported the feasibility of our system. The areas of BBB disruption obtained with this method were large enough to cover a typical circumscribed cerebral tumor mass. The inherent advantages of our BBB opening method include an improved portability, the possibility to obtain fairly wide areas of BBB opening and a low incidence of hemorrhagic complications. In addition, our system has the potential to reduce the need for image guidance for treating superficial brain lesions., (2010 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Background: This study aimed to examine: 1) the relationship between being a runaway and the time since the first absconding event and adolescent substance use; 2) whether different kinds of psychoactive substances have a different temporal relationship to the first absconding event; and 3) whether the various reasons for the first absconding event are associated with different risks of substance use., Methods: Participants were drawn from the 2004-2006 nationwide outreach programs across 26 cities/towns in Taiwan. A total of 17,133 participants, age 12-18 years, who completed an anonymous questionnaire on their experience of running away and substances use and who were now living with their families, were included in the analysis., Results: The lifetime risk of tobacco, alcohol, betel nut, and illegal drug/inhalant use increased steadily from adolescents who had experienced a trial runaway episode (one time lasting or= 2 times or lasting > 1 day), when compared to those who had never ran away. Adolescents who had their first running away experience > 6 months previously had a greater risk of betel nut or illegal drug/inhalant use over the past 6-months than those with a similar experience within the last 6 months. Both alcohol and tobacco use were most frequently initiated before the first running away, whereas both betel nut and illegal drug/inhalant use were most frequently initiated after this event. When adolescents who were fleeing an unsatisfactory home life were compared to those who ran away for excitement, the risk of alcohol use was similar but the former tended to have a higher risk of tobacco, betel nut, and illegal drug/inhalant use., Conclusions: More significant running away and a longer time since the first absconding experience were associated with more advanced substance involvement among adolescents now living in a family setting. Once adolescents had left home, they developed additional psychoactive substance problems, regardless of their reasons for running away. These findings have implications for caregivers, teachers, and healthcare workers when trying to prevent and/or intervening in adolescent substance use.

Metazoan development requires complex mechanisms to generate cells with diverse function. Alternative splicing of pre-mRNA not only expands proteomic diversity but also provides a means to regulate tissue-specific molecular expression. The N-Cadherin gene in Drosophila contains three pairs of mutually-exclusive alternatively-spliced exons (MEs). However, no significant differences among the resulting protein isoforms have been successfully demonstrated in vivo. Furthermore, while the N-Cadherin gene products exhibit a complex spatiotemporal expression pattern within embryos, its underlying mechanisms and significance remain unknown. Here, we present results that suggest a critical role for alternative splicing in producing a crucial and reproducible complexity in the expression pattern of arthropod N-Cadherin. We demonstrate that the arthropod N-Cadherin gene has maintained the three sets of MEs for over 400 million years using in silico and in vivo approaches. Expression of isoforms derived from these MEs receives precise spatiotemporal control critical during development. Both Drosophila and Tribolium use ME-13a and ME-13b in "neural" and "mesodermal" splice variants, respectively. As proteins, either ME-13a- or ME-13b-containing isoform can cell-autonomously rescue the embryonic lethality caused by genetic loss of N-Cadherin. Ectopic muscle expression of either isoform beyond the time it normally ceases leads to paralysis and lethality. Together, our results offer an example of well-conserved alternative splicing increasing cellular diversity in metazoans., Competing Interests: The authors have declared that no competing interests exist.

The shape of a neuron, its morphological signature, dictates the neuron's function by establishing its synaptic partnerships. Here, we review various anatomical methods used to reveal neuron shape and the contributions these have made to our current understanding of neural function in the Drosophila brain, especially the optic lobe. These methods, including Golgi impregnation, genetic reporters, and electron microscopy (EM), necessarily incorporate biases of various sorts that are easy to overlook, but that filter the morphological signatures we see. Nonetheless, the application of these methods to the optic lobe has led to reassuringly congruent findings on the number and shapes of neurons and their connection patterns, indicating that morphological classes are actually genetic classes. Genetic methods using, especially, GAL4 drivers and associated reporters have largely superceded classical Golgi methods for cellular analyses and, moreover, allow the manipulation of neuronal activity, thus enabling us to establish a bridge between morphological studies and functional ones. While serial-EM reconstruction remains the only reliable, albeit labor-intensive, method to determine actual synaptic connections, genetic approaches in combination with EM or high-resolution light microscopic techniques are promising methods for the rapid determination of synaptic circuit function.

Immunity has emerged as a popular health concept across different cultures, in particular concerning persons with human immunodeficiency virus (HIV). Attentiveness to immune status is encouraged and governed by a powerful clinical and public health surveillance system where two surrogate markers, CD4 counts and viral load, are chosen to monitor not only the effects of the biomedical intervention ART (antiretroviral treatment) but also individuals' effort in adherence and improving lifestyle practices. By interviewing 103 HIV participants, we delineate the reality they encountered while living with these two markers. We explore how they, in response to the doctrine surrounding the markers, shaped their peculiar immunological literacy and beliefs, and tactics for enhancing immunity. We found that the assumed validity of CD4 counts in health surveillance was challenged. The participants' conceptualisation of immunity was largely pluralistic, characterised by a blending of biomedical knowledge and Chinese health concepts and worldviews, strongly reflecting idiosyncrasy and eclecticism rather than universalism in reasoning about these markers and their relevance to immune status and overall wellbeing. Living with clinical markers is becoming a common experience in daily life; their meanings, their impacts on laypersons, and the utility claimed for them by the biomedical community, need further scrutiny.

Drosophila vision is mediated by inputs from three types of photoreceptor neurons; R1-R6 mediate achromatic motion detection, while R7 and R8 constitute two chromatic channels. Neural circuits for processing chromatic information are not known. Here, we identified the first-order interneurons downstream of the chromatic channels. Serial EM revealed that small-field projection neurons Tm5 and Tm9 receive direct synaptic input from R7 and R8, respectively, and indirect input from R1-R6, qualifying them to function as color-opponent neurons. Wide-field Dm8 amacrine neurons receive input from 13-16 UV-sensing R7s and provide output to projection neurons. Using a combinatorial expression system to manipulate activity in different neuron subtypes, we determined that Dm8 neurons are necessary and sufficient for flies to exhibit phototaxis toward ultraviolet instead of green light. We propose that Dm8 sacrifices spatial resolution for sensitivity by relaying signals from multiple R7s to projection neurons, which then provide output to higher visual centers.

Complementary and alternative medicine (CAM) has been characterized by prevalence, cost, and patterns of use. Factors determining its utilization have also been analyzed, either generally or for specific diseases, but few studies have considered the determinants of its frequency of use. Taiwan's pluralistic health care system and comprehensive insurance program covering Western medicine and traditional Chinese medicine (TCM) provide an interesting case to explore what forms of CAM people use, why and how often they use them. By using Taiwan's 2001 National Health Interview Survey and linking it with National Health Insurance (NHI) claims data, this study aims to investigate the socio-demographic, economic, behavioral and health determinants of use and frequency of use for both non-covered and covered CAM in Taiwan. The former consists of services practiced by non-regulated or non-NHI contracted practitioners and the latter includes those TCM covered by NHI. Our study showed that the determinants of using non-covered and covered CAM differ with respect to socio-demographic and behavioral factors, and health needs. Our evidence suggests that future CAM research must delineate between use and frequency of use to better understand the underlying factors contributing to initiation and continuity of CAM use.

Objective: This study examined the extent to which youthful alcohol consumption and the initiation of tobacco, betel nut, and other illegal drugs may differ by their first drinking context in Taiwan-a society with social norms that are more tolerant of underage drinking., Method: In 2004, in a nationally representative sample of 11,943 school-attending youth ages 15-18, information pertaining to sociodemographic characteristics, problem behaviors, lifetime experiences of alcohol, tobacco, betel nut, and illegal drugs, as well as psychoactive, drug-specific age of initiation, context at first use, average frequency, and recency of use, was assessed by anonymous questionnaires., Results: Youth who had their first alcoholic beverages in entertainment settings or at friends' houses were more likely to become frequent drinkers. After adjustment for socioeconomic background and problem behaviors, having had the first drink in entertainment settings was associated with a faster progression into the initiation of illegal drugs (hazard ratio [HR]=2.5, 95% confidence interval [CI]: 1.5-4.0) and betel nut (HR=1.5, 95% CI: 1.1-2.1)., Conclusions: Youthful drinking pattern and transition from alcohol to betel nut and illegal drugs may vary modestly by the first drinking context. This context may be recognized as a proxy variable to identify youth at a higher risk for alcohol and other drug problems and to devise context-based educational or prevention programs.

The organization of neuronal wiring into layers and columns is a common feature of both vertebrate and invertebrate brains. In the Drosophila visual system, each R7 photoreceptor axon projects within a single column to a specific layer of the optic lobe. We refer to the restriction of terminals to single columns as tiling. In a genetic screen based on an R7-dependent behavior, we identified the Activin receptor Baboon and the nuclear import adaptor Importin-alpha3 as being required to prevent R7 axon terminals from overlapping with the terminals of R7s in neighboring columns. This tiling function requires the Baboon ligand, dActivin, the transcription factor, dSmad2, and retrograde transport from the growth cone to the R7 nucleus. We propose that dActivin is an autocrine signal that restricts R7 growth cone motility, and we demonstrate that it acts in parallel with a paracrine signal that mediates repulsion between R7 terminals.

In the eye, visual information is segregated into modalities such as color and motion, these being transferred to the central brain through separate channels. Here, we genetically dissect the achromatic motion channel in the fly Drosophila melanogaster at the level of the first relay station in the brain, the lamina, where it is split into four parallel pathways (L1-L3, amc/T1). The functional relevance of this divergence is little understood. We now show that the two most prominent pathways, L1 and L2, together are necessary and largely sufficient for motion-dependent behavior. At high pattern contrast, the two pathways are redundant. At intermediate contrast, they mediate motion stimuli of opposite polarity, L2 front-to-back, L1 back-to-front motion. At low contrast, L1 and L2 depend upon each other for motion processing. Of the two minor pathways, amc/T1 specifically enhances the L1 pathway at intermediate contrast. L3 appears not to contribute to motion but to orientation behavior.

It has been noted that workplace violence most frequently occurs in psychiatric settings. The purpose of this study was to explore the workplace violence, including violence situation, victims' feeling, and the prevention strategies, on workers caring for long-term institutionalized schizophrenic patients in Taiwan. We conducted a face-to-face, in-depth, and semi-structured interview with 13 health care workers suffering from physical violence and/or sexual harassment by patients in 2002. First, the interviews were taped and/or paper-notes recorded, then transcribed, organized, and analyzed. Results found that all of the victims alleged they did not receive enough post-incident support, and more than a half of the victims could not call others for help during the violence. To avoid further attack, most victims offered prevention strategies which were considered valuable for establishing guidelines. However, some victims regarded workplace violence as inevitable and part of the job. The most common situations of workplace violence were during routine ward inspections, especially when the victims were alone. The most serious psychological harm was post-traumatic stress disorder (PTSD). In conclusion, we recommended a re-engineering of the organization to a supportive and safe working environment for prevention of workplace violence in the study hospital.

Drosophila N-cadherin (CadN) is an evolutionarily conserved, atypical classical cadherin, which has a large complex extracellular domain and a catenin-binding cytoplasmic domain. We have previously shown that CadN regulates target selection of R7 photoreceptor axons. To determine the functional domains of CadN, we conducted a structure-function analysis focusing on its in vitro adhesive activity and in vivo function in R7 growth cones. We found that the cytoplasmic domain of CadN is largely dispensable for the targeting of R7 growth cones, and it is not essential for mediating homophilic interaction in cultured cells. Instead, the cytoplasmic domain of CadN is required for maintaining proper growth cone morphology. Domain swapping with the extracellular domain of CadN2, a related but non-adhesive cadherin, revealed that the CadN extracellular domain is required for both adhesive activity and R7 targeting. Using a target-mosaic system, we generated CadN mutant clones in the optic lobe and examined the target-selection of genetically wild-type R7 growth cones to CadN mutant target neurons. We found that CadN, but neither LAR nor Liprin-alpha, is required in the medulla neurons for R7 growth cones to select the correct medulla layer. Together, these data suggest that CadN mediates homophilic adhesive interactions between R7 growth cones and medulla neurons to regulate layer-specific target selection.

Background: Type 2 diabetes is becoming more prevalent and its successful management relies on patients' self-care behaviours. Measures focusing on patients' perceptions can be effective behavioural interventions., Aim: To gain insight into the perceptions of patients with diabetes, especially ideas of the illness course and perceived severity, and their impacts on self-care behaviour., Design of Study: Qualitative approach with in-depth patient interviews (n = 22) and seven focus groups (n = 53)., Setting: A rural town in Taiwan., Method: The interview protocol was mainly derived from Kleinman's explanatory model. Purposive sampling strategies of maximum variation were used. The transcript of the interviews was analysed with editing and immersion/crystallisation styles., Results: Diabetes is regarded as an incurable, inevitably deteriorating disorder of sugar metabolism with many chronic complications. Patients thought that renal injury, followed by blindness, leg amputation, and poor peripheral circulation, were the most frequent complications. They also assessed their perceived severity of the disease at specific points in time through different indicators in their daily lives, such as sugar level, presence of complications, and medications used. Patients felt that these aspects progressed concurrently and that the illness course followed a unidimensional process. The ever-increasing doses of medication was considered by these patients to be a side-effect of the drugs taken., Conclusion: Physicians should clarify with their patients that the risks of uraemia, blindness, and leg amputation are less prevalent than expected and that patients should pay more attention to cardiovascular complications. Certain oral hypoglycaemic agents may not cause a vicious cycle of ever-increasing doses of medication and the drugs that need to be taken should not be seen as indicators of severity but, rather, measures taken to prevent the diabetes becoming severe in the future.

Fly visual circuits are organized into lattice-like arrays and layers. Recent genetic studies have provided insights into how these reiterated structures are assembled through stepwise processes and how precise connections are established during development. Afferent-derived morphogens, such as Hedgehog, play a key role in organizing the overall structure by inducing and recruiting target neurons and glia. In turn, the target-derived ligand DWnt4 guides Frizzled2-expressing photoreceptor afferents to their proper destination. Photoreceptor afferents select specific synaptic targets by forming adhesive interactions and regulating actin cytoskeleton in growth cones. Target specificity is probably achieved by restricting the expression of adhesive molecules, such as Capricious, to appropriate presynaptic and postsynaptic partners, and by differentially regulating the function of broadly expressed adhesive molecules such as N-cadherin.

The aim of this study is to assess the association linking employment experience with alcohol, tobacco, and betel nut involvement among youth in Taiwan. In 2004, an outreach program was conducted during weekdays to recruit youth sample in seven major geographic regions. A total of 5886 youth aged 12-18 years drawn from 26 cities or towns were assessed by a two-page anonymous self-administered questionnaire, including sociodemographic characteristics, employment-, development-, and drug-related experiences. In Taiwan, youthful experience of alcohol, tobacco, and polydrug use varies by employment status, work intensity, and job type. Holding a full-time job and working in certain settings (e.g., grocery, restaurants) were found associated with an excess of drug-using behaviors. With taking age, male gender, family context, disposable allowance, and school attendance into account, working youths were two to four times as likely to have recent drug involvement than their non-working counterparts, especially for tobacco and polydrug (OR=3.32, 95% CI: 2.58-4.27, p<0.001; OR=3.76, 95% CI: 2.76-5.13, p<0.001). Youths in the labor force emerge as a subgroup experiencing greater use of alcohol, tobacco, betel nut, and polydrug. Future prevention programs may target this high-risk group to reduce possible drug-related negative consequences in developmental and health domains in Taiwan.

Drosophila N-cadherin (CadN) is an evolutionarily conserved classic cadherin which has a large, complex extracellular domain and a catenin-binding cytoplasmic domain. The CadN locus contains three modules of alternative exons (7a/b, 13a/b, and 18a/b) and undergoes alternative splicing to generate multiple isoforms. Using quantitative transcript analyses and green fluorescent protein-based cell sorting, we found that during development CadN alternative splicing is regulated in a temporal but not cell-type-specific fashion. In particular, exon 18b is predominantly expressed during early developmental stages, while exon 18a is prevalent at the late developmental and adult stages. All CadN isoforms share the same molecular architecture but have different sequences in their extracellular and transmembrane domains, suggesting functional diversity. In vitro quantitative cell aggregation assays revealed that all CadN isoforms mediate homophilic interactions, but the isoforms encoded by exon 18b have a higher adhesive activity than those by its alternative, 18a. Domain-swapping experiments further revealed that the different sequences in the transmembrane domains of isoforms are responsible for their differential adhesive activities. CadN alternative splicing might provide a novel mechanism to fine-tune its adhesive activity at different developmental stages or to restrict the use of high-affinity 18b-type isoforms at the adult stage.

Human (h) DNA topoisomerase I has been identified as a major SUMO1 target in camptothecin-treated cells. In response to TOP1-mediated DNA damage induced by camptothecin, multiple SUMO1 molecules are conjugated to the N-terminal domain of a single TOP1 molecule. To investigate the molecular mechanism of SUMO1 conjugation to TOP1, an in vitro system using purified SAE1/2, Ubc9, SUMO1, and TOP1 peptides was developed. Consistent with results from in vivo studies, multiple SUMO1 molecules were found to be conjugated to the N-terminal domain of a single TOP1 molecule. Systematic analysis has identified a single major SUMO1 conjugation site located between amino acid residues 110 and 125 that contains a single lysine residue at 117 (Lys-117). Using a short peptide spanning this region, we showed that a poly-SUMO1 chain was assembled in this peptide at Lys-117. Interestingly, a Ubc9-poly-SUMO1 intermediate had accumulated to a high level when the sumoylation assay was performed in the absence of hTOP1 substrate, suggesting a possibility that the poly-SUMO1 chain is formed on Ubc9 first and then transferred en bloc onto hTOP1. This is the first definitive demonstration of the assembly of a poly-SUMO1 chain on protein substrate. These results offer new insight into hTOP1 polysumoylation in response to TOP1-mediated DNA damage and may have general implications in protein polysumoylation.

NF-E2 is a transcription activator for the regulation of a number of erythroid- and megakaryocytic lineage-specific genes. Here we present evidence that the large subunit of mammalian NF-E2, p45, is sumoylated in vivo in human erythroid K562 cells and in mouse fetal liver. By in vitro sumoylation reaction and DNA transfection experiments, we show that the sumoylation occurs at lysine 368 (K368) of human p45/NF-E2. Furthermore, p45 sumoylation enhances the transactivation capability of NF-E2, and this is accompanied by an increase of the NF-E2 DNA binding affinity. More interestingly, we have found that in K562 cells, the beta-globin gene loci in the euchromatin regions are predominantly colocalized with the nuclear bodies promyelocytic leukemia protein (PML) oncogenic domains that are enriched with the PML, SUMO-1, RNA polymerase II, and sumoylatable p45/NF-E2. Chromatin immunoprecipitation assays further showed that the intact sumoylation site of p45/NF-E2 is required for its binding to the DNase I-hypersensitive sites of the beta-globin locus control region. Finally, we demonstrated by stable transfection assay that only the wild-type p45, but not its mutant form p45 (K368R), could efficiently rescue beta-globin gene expression in the p45-null, erythroid cell line CB3. These data together point to a model of mammalian beta-like globin gene activation by sumoylated p45/NF-E2 in erythroid cells.

Purpose: To evaluate, using a randomized trial, whether a web-based self-administered questionnaire (web SAQ) can improve the reporting rate of substance use in adolescents compared with a paper-and-pencil self-administered questionnaire (paper SAQ)., Methods: Students of junior high, senior high, and vocational high schools in Taipei City and County were selected by a stratified, two-stage, probability proportional to size, random sampling. For each class selected, half of the students were randomly assigned to paper SAQ (n = 990) and the other half to web SAQ (n = 928). The inverse of the sampling probability for each individual was then used as sampling weight in the estimation of prevalence and logistic regression analysis., Results: For readily available substances, the lifetime prevalence in the web SAQ group was significantly higher for alcohol use and borderline higher for tobacco and betel nut use compared to those of the paper SAQ group. For illicit drug use, the lifetime prevalence for the web SAQ group was significantly higher for the use of amphetamines, and borderline higher for ketamine. In multiple logistic regression analysis, the differences between the two groups in the use of alcohol, tobacco, and amphetamines remained significant. Boys, as well as both junior-high and vocational high school students who responded using the web SAQ, were more likely to report alcohol or tobacco use than those using the paper SAQ., Conclusions: Web SAQ leads to higher reporting rates of commonly used substances in adolescents compared with those of paper SAQ.

The newly emerged concept of integrative medicine may provoke a closer investigation into the pattern of biomedicine use in the context of medical pluralism. In this study, I propose two concepts to examine the complicated cognitive and behavioural responses to biomedicine (Western medicine, xi-yi) in relation to the use of non-biomedical therapies in Taiwan, a society with renowned medical pluralism. Data came from a nation-wide telephone survey conducted during September 2002 among community-resident population aged 20 and older. The sample includes 1517 respondents. The first concept--antibiomedicine--includes three indicators to measure an individual's negative stance on xi-yi: overall competence, capability to cure from within, and side effects. Combined, these three indicators were further constructed into a single composite index: antibiomedicine beliefs. Integrative health seeking tackled two aspects of health seeking: selective use and adaptive use. The former concerns particularly the use of specific ingredients of biomedicine. In this study, emphasis was placed on the diagnosis versus treatment of xi-yi. The latter was focussed on the strategic uses of xi-yi in the face of its limitation and incompetence. Three types of adaptive health use were identified: alternative type, complementary type, and exclusive type. Results of the analyses indicate that antibiomedicine belief held explanatory potential to selective use and adaptive use of xi-yi. The study sheds light on further exploring the blending of health-seeking practices and "hybrid" medicine. It is suggested that novel explanatory constructs and more sophisticated study designs should be developed to articulate the sequential of pluralistic health-seeking process.

Aims: Type 2 diabetes is becoming more prevalent in Taiwan. Growing evidence suggests a patient-centred approach is more effective in facilitating self-management than a professional-centred one. The aim of this qualitative study was to investigate Chinese diabetic patients' perceptions about their illness and treatment strategies to facilitate patient-centred, culture-sensitive clinical skills., Methods: We used in-depth interviews to collect perspectives from 22 participants recruited from a rural Taiwan community. All interviews were audio-taped and the transcripts were analysed by editing and immersion/crystallization. Emerging themes were compared with current medical knowledge to determine their clinical significance., Results: Generally, Chinese diabetic patients had variable perceptions about different treatment strategies. All agreed that dietary restriction and exercise were beneficial. The former, mainly understood as reducing carbohydrate intake, was thought to be most important; exercise, to the point of sweating, was seen as a way to eliminate pharmaceutical toxins. Taking medicine was regarded with ambivalent attitudes due to concerns about adverse effects (especially renal injury)., Conclusions: Patients regarded all treatment strategies as integrative and intertwined in daily life. There are three misconceptions which we found should be clarified during medical consultations: (i) focusing on sugar-control only; (ii) benefit of sweating to eliminate toxins; (iii) fear of renal toxicity of hypoglycaemic agents. The renaming of diabetes, to such as 'metabolic syndrome', may bring new, acceptable insight to Chinese diabetic patients.

Visual information received from the three types of photoreceptor neurons (R1-R6, R7 and R8) in the fly compound eyes converges to the external part of the medulla neuropil (M1-M6 layers) in a layer-specific fashion: R7 and R8 axons terminate at the M6 and M3 layers, respectively, whereas lamina neurons (L1-L5) relay R1-R6 to multiple medulla layers (M1-M5). Here, we show that during development, R7 and R8 neurons establish layer-specific projections in two separate stages: during the first stage, R7 and R8 axons sequentially target to the R7- and R8-temporary layers, respectively; and at the second stage, R7 and R8 growth cones progress synchronously to their destined layers. Using a set of mutations that delete different afferent subsets or alter R7 connectivity, we defined the mechanism of layer selection. We observed that R8, R7 and L1-L5 afferents target to their temporary layers independently, suggesting that afferent-target, but not afferent-afferent, interactions dictate the targeting specificity. N-cadherin is required in the first stage for R7 growth cones to reach and remain in the R7-temporary layer. The Ncad gene contains three pairs of alternatively spliced exons and encodes 12 isoforms. However, expressing a single Ncad isoform in Ncad mutant R7s is sufficient to rescue mistargeting phenotypes. Furthermore, Ncad isoforms mediate promiscuous heterophilic interactions in an in vitro cell-aggregation assay. We propose that Ncad isoforms do not form an adhesion code; rather, they provide permissive adhesion between R7 growth cones and their temporary targets.

Our structural comparison of the TIM barrel metal-dependent hydrolase(-like) superfamily suggests a classification of their divergent active sites into four types: alphabeta-binuclear, alpha-mononuclear, beta-mononuclear, and metal-independent subsets. The d-aminoacylase from Alcaligenes faecalis DA1 belongs to the beta-mononuclear subset due to the fact that the catalytically essential Zn(2+) is tightly bound at the beta site with coordination by Cys(96), His(220), and His(250), even though it possesses a binuclear active site with a weak alpha binding site. Additional Zn(2+), Cd(2+), and Cu(2+), but not Ni(2+), Co(2+), Mg(2+), Mn(2+), and Ca(2+), can inhibit enzyme activity. Crystal structures of these metal derivatives show that Zn(2+) and Cd(2+) bind at the alpha(1) subsite ligated by His(67), His(69), and Asp(366), while Cu(2+) at the alpha(2) subsite is chelated by His(67), His(69) and Cys(96). Unexpectedly, the crystal structure of the inactive H220A mutant displays that the endogenous Zn(2+) shifts to the alpha(3) subsite coordinated by His(67), His(69), Cys(96), and Asp(366), revealing that elimination of the beta site changes the coordination geometry of the alpha ion with an enhanced affinity. Kinetic studies of the metal ligand mutants such as C96D indicate the uniqueness of the unusual bridging cysteine and its involvement in catalysis. Therefore, the two metal-binding sites in the d-aminoacylase are interactive with partially mutual exclusion, thus resulting in widely different affinities for the activation/attenuation mechanism, in which the enzyme is activated by the metal ion at the beta site, but inhibited by the subsequent binding of the second ion at the alpha site.

Isodiospyrin is a natural product from the plant Diospyros morrisiana, which consists of an asymmetrical 1,2-binaphthoquinone chromophore. Isodiospyrin exhibits cytotoxic activity to tumor cell lines but very little is known about its cellular target and mechanism of action. Unlike the prototypic human topoisomerase I (htopo I) poison camptothecin, isodiospyrin does not induce htopo I-DNA covalent complexes. However, isodiospyrin antagonizes camptothecin-induced, htopo I-mediated DNA cleavage. Binding analysis indicated that isodiospyrin binds htopo I but not DNA. These results suggest that isodiospyrin inhibits htopo I by direct binding to htopo I, which limits htopo I access to the DNA substrate. Furthermore, isodiospyrin exhibits strong inhibitory effect on the kinase activity of htopo I toward splicing factor 2/alternate splicing factor in the absence of DNA. Thus, these findings have important implications on naphthoquinone and its derivatives' cellular mode of actions, i.e. these novel DNA topoisomerase I inhibitors can prevent both DNA relaxation and kinase activities of htopo I.

It has been proposed that the topoisomerase II (TOP2)beta-DNA covalent complex arrests transcription and triggers 26S proteasome-mediated degradation of TOP2beta. It is unclear whether the initial trigger for proteasomal degradation is due to DNA damage or transcriptional arrest. In the current study we show that the TOP2 catalytic inhibitor 4,4-(2,3-butanediyl)-bis(2,6-piperazinedione) (ICRF-193), which traps TOP2 into a circular clamp rather than the TOP2-DNA covalent complex, can also arrest transcription. Arrest of transcription, which is TOP2beta-dependent, is accompanied by proteasomal degradation of TOP2beta. Different from TOP2 poisons and other DNA-damaging agents, ICRF-193 did not induce proteasomal degradation of the large subunit of RNA polymerase II. These results suggest that proteasomal degradation of TOP2beta induced by the TOP2-DNA covalent complex or the TOP2 circular clamp is due to transcriptional arrest but not DNA damage. By contrast, degradation of the large subunit of RNA polymerase II is due to a DNA-damage signal.

This paper intends to investigate the connection between HIV transmission knowledge and prejudicial attitudes towards people with HIV/AIDS (PWAs), with an emphasis on exploring the pattern of cognitive profile in response to knowledge questions. Data for the present study were derived from the 'Health Attitudes and Health Seeking Behavior Study', a telephone survey of a nationally representative sample, aged 20 to 70, from April to May 1997 in Taiwan. A total of 2,471 respondents who had heard of AIDS and knew that it was infectious were included in the analysis. Based on answers to four transmission-route items (blood transfusion, mother-foetus, sexual contacts, needle sharing) and two casual-contact items (shaking hands and sharing utensil), a variable 'pattern of knowledge performance' was constructed, by which the respondents were clustered into five knowledge groups. Bivariate and multivariate analyses illustrated the greater explanatory power of pattern of knowledge performance rather than additive scoring of knowledge items to PWAs' prejudice. Moreover, it was the responses to casual-contact rather than transmission-route questions that made a greater contribution to PWAs' prejudice. Special attention is given to the possible perceptual undertaking inherent in the five types of knowledge group. To implement effective AIDS prevention campaigns and interventions, the design for increasing the risk perception of the correct HIV transmission routes should differ from that of reducing the risk perception of the casually transmitted routes.

Purpose: Using the perspectives of age, period, and cohort (APC) effects, this study explored the changes in attitudes toward supporting parents in Taiwan., Design and Methods: Population-representative cross-sectional data taken at 1984, 1990, and 1995 from the Social Change Survey in Taiwan were synthesized. Cohort tables and multi-nominal logistic regression were used to analyze the APC effects., Results: Period and age effects were found in the change in attitudes toward supporting parents. Agreement on living with sons or children has slowly decreased. Younger persons agree more than older ones in attitudes toward parents living with their married son or children. There was a reduction in the differences among cohorts across periods. There was no demonstration of cohort effect in this study., Implications: The results indicate that for married children, living with parents is no longer popular in Taiwan society. Social policy should address the unmet needs of elderly people in assistance with daily living.

DNA topoisomerase II (TOP2) cleavable complexes represent an unusual type of DNA damage characterized by reversible TOP2-DNA cross-links and DNA double strand breaks. Many antitumor drugs and physiological stresses are known to induce TOP2 cleavable complexes leading to apoptotic cell death and genomic instability. However, the molecular mechanism(s) for repair of TOP2 cleavable complexes remains unclear. In the current studies, we show that TOP2 cleavable complexes induced by the prototypic TOP2 poison VM-26 are proteolytically degraded by the ubiquitin/26 S proteasome pathway. Surprisingly the TOP2beta isozyme is preferentially degraded over TOP2alpha isozyme. In addition, transcription inhibitors such as 5,6-dichlorobenzimidazole riboside and camptothecin can substantially block VM-26-induced TOP2beta degradation. These results are consistent with a model in which the repair of TOP2beta cleavable complexes may involve transcription-dependent proteolysis of TOP2beta to reveal the protein-concealed double strand breaks.

A method for the preparation of an immunogen containing multiple copies of a self-peptide in linear alignment was designed in order to overcome the difficulty of inducing an immune response to poorly immunogenic peptide antigens. DNA fragments encoding multiple repeats of the self-peptide were generated by a new technique, termed template-repeated polymerase chain reaction (TR-PCR), which could be subcloned into an expression vector for production of peptide repeats as an immunogen. This approach was tested by constructing fusion proteins containing the receptor-binding domain of Pseudomonas exotoxin A and multiple copies of the 10-residue sequence of the peptide hormone gonadotropin-releasing hormone (GnRH). Immunization of female rabbits with the immunogen that contained the exotoxin receptor-binding domain and 12 copies of GnRH (PEIa-GnRH12) resulted in the generation of high-titer antibodies specific for GnRH. Although at equal molar basis of the GnRH moiety, the immunogen that contained single copy of GnRH (PEIa-GnRH1) induced low-titer anti-GnRH antibodies. These observations suggest that the presence of multiple peptide repeats is a key factor in eliciting an immune response. In addition, anti-GnRH antibodies effectively neutralized GnRH activity in vivo, as demonstrated by the degeneration of the ovaries in the injected rabbits. Because anti-GnRH antibody could be functionally analogous to GnRH antagonist, which has been used to treat patients with ovarian cancer, vaccination of PEIa-GnRH12 presents a potential therapeutic application for the treatment of GnRH-sensitive ovarian cancer.

Gene therapy is defined as the delivery of a functional gene for expression in somatic tissues with the intent to cure a disease. Thus, highly efficient gene transfer is essential for gene therapy. Receptor-mediated gene delivery can offer high efficiency in gene transfer, but several technical difficulties need to be solved. In this study, we first examined the DNA binding regions of the human DNA topoisomerase I (Topo I), using agarose gel mobility shift assay, in order to identify sites of noncovalent binding of human DNA Topo I to plasmid DNA. We identified four DNA binding regions in human DNA Topo I. They resided in aa 51-200, 271-375, 422-596, and 651-696 of the human DNA Topo I. We then used one of the four regions as a DNA binding protein fragment in the construction of a DNA delivery vehicle. Based on the known functional property of each Pseudomonas exotoxin A (PE) domain and human DNA Topo I, we fused the receptor binding and membrane translocation domains of PE with a highly positively charged DNA binding region of the N-terminal 198 amino acid residues of human DNA Topo I. The resulting recombinant protein was examined for DNA binding in vitro and transfer efficiency in cultured cells. The results show that this DNA delivery protein is a general DNA delivery vehicle without DNA sequence, topology, and cell-type specificity. The DNA delivery protein could be used to target genes of interest into cells for genetic and biochemical studies. Therefore, this technique can potentially be applied to cancer gene therapy.

This paper reports ethnographic and statistical data on the indigenous Chinese concept of constitution (ti-zhi) and its association with health status. The data were obtained through in-depth interviews with 203 Chinese elderly residing in Taipei and Los Angeles. The informants used several dimensions to characterize their constitutions. They also described how their constitutions originated and were expressed over the lifecourse. The association between these characterizations of constitution and reported number of symptoms/diseases, self-rated health status and satisfaction with health were examined statistically. These analyses indicate that characterizations of constitution as strong/weak or as hot/cold, have significant but moderate associations with the indicators of health status.

A camptothecin-resistant cell line that exhibits more than 600-fold resistance to camptothecin, designated CPT(R)-2000, was established from mutagen-treated A2780 ovarian cancer cells. CPT(R)-2000 cells also exhibit 3-fold resistance to a DNA minor groove-binding ligand Ho33342, a different class of mammalian DNA topoisomerase I inhibitors. However, CPT(R)-2000 cells exhibit no cross-resistance toward drugs such as Adriamycin, amsacrine, vinblastine, and 4'-dimethyl-epipodophyllotoxin. The mRNA, protein levels, and enzyme-specific activity of DNA topoisomerase I are relatively the same in parental and CPT(R)-2000 cells. However, unlike the DNA topoisomerase I activity of parental cells, which can be inhibited by camptothecin, that of CPT(R)-2000 cells cannot. In addition, parental cells after camptothecin treatment results in a decrease in the level of DNA topoisomerase I, whereas CPT(R)-2000 cells are insensitive to camptothecin treatment. These results suggested that the mechanism of camptothecin resistance is most likely due to a DNA topoisomerase I structural mutation. This notion is supported by DNA sequencing results confirming that DNA topoisomerase I of CPT(R)-2000 is mutated at amino acid residues Gly717 to Val and Thr729 to Ile. We also used the yeast system to examine the mutation(s) responsible for camptothecin resistance. Our results show that each single amino acid change results in partial resistance, and the double mutation gives a synergetic effect on camptothecin resistance. Because both mutation sites are near the catalytic active center, this observation raises the possibility that camptothecin may act at the vicinity of the catalytic active site of the enzyme-camptothecin-DNA complex.

Studies pertaining to health promoting behavior in daily life have received scant attention among medical anthropologists. The present study addresses this issue by means of an empirical analysis of perceptions and behaviors concerning a daily food item -eggs. Data were collected via in-depth interviews as well as participant observation in four retirement homes-two in Los Angeles and two in Taipei, Taiwan. The results reveal that practices of egg-restriction are pervasive throughout the four homes. Cholesterol has become a commonly-discussed issue in the daily lives of the 203 residents interviewed, and many of them were found to be preoccupied with the risk involved in excess consumption (especially of egg yolks) and increased serum cholesterol levels. Four forces: health professionals, family members, peer groups and mass media play important roles in constructing egg-consumption behaviors among the elderly subjects. The cognitive, psychological and behavioral impact of health information on elderly subjects has been discussed herein. It may be argued that the 'egg issue' reflects a shift in previous health paradigm thinking due to the biomedicalization of health promotion among Chinese elderly.

We examined data on elderly Latinos to identify structural barriers that influence the use of a visiting nurse, home health aide, and/or homemaker, and to investigate possible cultural influence on use. Data are from the 1988 Commonwealth Fund Commission's national survey of 2,299 Latinos age 65 and over. Logistic equations are estimated for all elderly Latinos, those with a hospitalization in the past year, and those without a hospitalization. Need factors consistently increase the odds of using services. The significance of Medicaid and poverty income demonstrates income barriers to community-based care. Living arrangements improve our models only for those with a hospitalization in the past year. Acculturation has no independent effect, although some other findings can be interpreted as cultural preferences. We conclude that a universal, public long-term care program would substantially reduce barriers faced by elderly Latinos, but that nonfinancial barriers are likely to continue.

Although evidence suggests that the morbidity and mortality of Latino elders (of any Hispanic ancestry) are similar to those of non-Latino whites, Latinos have higher rates of disability. Little is known about influences on the use of in-home health services designed to assist disabled Latino elders. We examine the effects of various cultural and structural factors on the use of visiting nurse, home health aide, and homemaker services. Data are from the Commonwealth Fund Commission's 1988 national survey of 2,299 Latinos aged 65 and older. Mexican-American elders are less likely than the average Latino to use in-home health services despite similar levels of need. Structural factors including insurance status are important reasons, but acculturation is not pertinent. Physicians should not assume that Latino families are taking care of their disabled elders simply because of a cultural preference. They should provide information and advice on the use of in-home health services when an older Latino patient is physically disabled.