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PubMed1998

Clinical development of atypical antipsychotics: research design and evaluation. Collaborative Working Group on Clinical Trial Evaluations.

Clinical trials support the efficacy and safety of new drugs on the market. They provide the United States Food and Drug Administration with the information needed to approve an Investigational New Drug application and are the basis for package inserts provided by the manufacturers that guide clinicians in the use of a new drug. Because clinical trials are vital to the effective and safe use of new drugs, it is important to understand who participates in them, what questions are answered by clinical trials, and what questions are raised. The reader who asks the proper questions about issues such as methodology, affiliations of the investigators, statistical analyses performed, location of study centers, and study populations will derive the most information from the report of a clinical trial.

Adult↗
PubMed1994

Genetic mapping of the Batten disease locus (CLN3) to the interval D16S288-D16S383 by analysis of haplotypes and allelic association.

CLN3, the gene for juvenile-onset neuronal ceroid lipofuscinosis (JNCL) or Batten disease, has been localized by genetic linkage analysis to chromosome 16p between loci D16S297 and D16S57. We have now further refined the localization of CLN3 by haplotype analysis using two new microsatellite markers from loci D16S383 and SPN in the D16S297-D16S57 interval on a larger collaborative family resource consisting of 142 JNCL pedigrees. Crossover events in 3 maternal meioses define new flanking markers for CLN3 and localize the gene to the interval at 16p12.1-p11.2 between D16S288 and D16S383, which corresponds to a genetic distance of 2.1 cM. Within this interval 4 microsatellite loci are in strong linkage disequilibrium with CLN3, and extended haplotype analysis of the associated alleles indicates that CLN3 is in closest proximity to loci D16S299 and D16S298.

Alleles↗
PubMed2001

A diffusion of innovations model of physician order entry.

OBJECTIVE: To interpret the results of a cross-site study of physician order entry (POE) in hospitals using a diffusion of innovations theory framework. METHODS: Qualitative study using observation, focus groups, and interviews. Data were analyzed by an interdisciplinary team of researchers using a grounded approach to identify themes. Themes were then interpreted using classical Diffusion of Innovations (DOI) theory as described by Rogers [1]. RESULTS: Four high level themes were identified: organizational issues; clinical and professional issues; technology implementation issues; and issues related to the organization of information and knowledge. Further analysis using the DOI framework indicated that POE is an especially complex information technology innovation when one considers communication, time, and social system issues in addition to attributes of the innovation itself. CONCLUSION: Implementation strategies for POE should be designed to account for its complex nature. The ideal would be a system that is both customizable and integrated with other parts of the information system, is implemented with maximum involvement of users and high levels of support, and is surrounded by an atmosphere of trust and collaboration.

Diffusion of Innovation↗
PubMed1992

Inducible cell contact signals regulate early activation gene expression during B-T lymphocyte collaboration.

B cells get help in the antibody response by presenting processed Ag to Th cells. We asked whether the Ag-presenting B cell must induce Th functions before receiving help, or whether B cell activation is a direct consequence of T cell recognition of Ag on the B cell surface. To obtain a prompt and sensitive indication of the receipt of growth signals, we measured mRNA levels of the immediate early genes, c-myc and egr-1, in T and B cells separated from Ag-specific B-T conjugates of normal, resting murine B cells and a Th line. Although Ag-dependent increases in B cell c-myc expression occur as early as 2 h after conjugation, early c-myc expression in the B cell was also seen when the Th cells were activated with immobilized anti-CD3 in the absence of Ag recognition. Therefore, T cell activation rather than Ag recognition per se appears to be responsible for the early c-myc signal in the B cells. The c-myc response in the B cell depends on induction of a contact-dependent helper function in the T cell, which is inhibitable by cyclosporin A acting on the T cell. Delivery of contact help is not blocked by anti-class II MHC antibody. Contact with activated Th cells induces a different pattern of immediate early gene expression from that induced by cross-linking the B cell Ag receptor.

Animals↗
PubMedDate not supplied

Spouse-pair similarity on the California Psychological Inventory with reference to husband's coronary heart disease.

The present article reports on the results of several comparisons between 45 adult males with diagnosed coronary heart disease (cases) and their wives and 50 adult males without coronary heart disease (noncases) and their wives recruited from the Western Collaborative Group Study. The California Psychological Inventory and a life satisfaction inventory were administered to the couples in the two types of families. Results indicate that although both sets of husbands and wives fell within the well-functioning range on the CPI, wives of cases were significantly more dominant and less flexible than wives of noncase husbands. Case husbands were significantly more dominant than noncase husbands. No mean differences existed between case and noncase husbands and wives on a variety of life satisfaction measures. Computation of spouse-pair correlations revealed a pattern of overall dissimilarity across the CPI scales for case couples and overall similarity for the noncase couples. The only scale on which case spouse pairs were significantly similar was one measuring depression. Noncase couples were significantly more similar than case couples on scales measuring sociability, self-acceptance, and socialization. Previous findings from the research literature in the fields of personality, cardiac rehabilitation, and assortative mating are used to generate three competing hypotheses relating the present findings to cross spouse disease associations.

Achievement↗
PubMed2001

Delineating bipolar II mixed states in the Ravenna-San Diego collaborative study: the relative prevalence and diagnostic significance of hypomanic features during major depressive episodes.

BACKGROUND: Depressive mixed state (DMX), defined by hypomanic features during a major depressive episode (MDE) is under-researched. Accordingly, study aims were to find DMX prevalence in unipolar major depressive disorder (MDD) and bipolar II depressive phase, to delineate the most common hypomanic signs and symptoms during DMX, and to assess their sensitivity and specificity for the diagnosis of DMX and bipolar II. METHODS: 161 unipolar and bipolar II MDE psychotropic drug- and substance-free consecutive outpatients were interviewed during an MDE with the Structured Clinical Interview for DSM-IV. DMX was defined at two threshold levels as an MDE with two or more (DMX2), and with three or more (DMX3) simultaneous intra-episode hypomanic signs and symptoms. RESULTS: DMX2 was present in 73.1% of bipolar II, and in 42.1% of unipolar MDD (P<0.000); DMX3 was present in 46.3% of bipolar II, and in 7.8% of unipolar MDD (P<0.000). The most common hypomanic manifestations during MDE were irritability, distractibility, and racing thoughts. Irritability had the best combination of sensitivity and specificity for the diagnosis of DMX2 and DMX3. Various combinations of irritability, distractibility, and racing thoughts correctly classified the highest number of DMX2 and DMX3, and had the strongest predictive power. DMX2 had high sensitivity and low specificity for bipolar II, whereas DMX3 had low sensitivity (46.3%) and high specificity (92.1%). LIMITATIONS: Single interviewer, cross-sectional assessment, and interviewing clinician not blind to patients' unipolar vs. bipolar status. CONCLUSIONS: When conservatively defined (>or = 3 intra-episode hypomanic signs and symptoms during MDE), DMX is prevalent in the natural history of bipolar II but uncommon in unipolar MDD. These findings have treatment implications, because of growing concerns that antidepressants may worsen DMX, which in turn may respond better to mood stabilizers. These data also have methodological implications for diagnostic practice: rather than solely depending on the vagaries of the patient's memory for past hypomanic episodes, the search for hypomanic features--ostensibly elation would not be one of those--during an index depressive episode could enhance the detection of bipolar II in otherwise pseudo-unipolar patients. Strict adherence to current clinical diagnostic interview instruments (e.g. the SCID) would make such detection difficult, if not impossible.

Adult↗
PubMed2006

NK and CD4 cells collaborate to protect against melanoma tumor formation in the brain.

NK cells represent a potent immune effector cell type that have the ability to recognize and lyse tumors. However, the existence and function of NK cells in the traditionally "immune-privileged" CNS is controversial. Furthermore, the cellular interactions involved in NK cell anti-CNS tumor immunity are even less well understood. We administered non-Ag-loaded, immature dendritic cells (DC) to CD8alpha knockout (KO) mice and studied their anti-CNS tumor immune responses. DC administration induced dramatic antitumor immune protection in CD8alpha KO mice that were challenged with B16 melanoma both s.c. and in the brain. The CNS antitumor immunity was dependent on both CD4+ T cells and NK cells. Administration of non-Ag-loaded, immature DC resulted in significant CD4+ T cell and NK cell expansion in the draining lymph nodes at 6 days postvaccination, which persisted for 2 wk. Finally, DC administration in CD8alpha KO mice was associated with robust infiltration of CD4+ T cells and NK cells into the brain tumor parenchyma. These results represent the first demonstration of a potent innate antitumor immune response against CNS tumors in the absence of toxicity. Thus, non-Ag-loaded, immature DC administration, in the setting of CD8 genetically deficient mice, can induce dramatic antitumor immune responses within the CNS that surpass the effects observed in wild-type mice. Our results suggest that a better understanding of the cross-talk between DC and innate immune cells may provide improved methods to vaccinate patients with tumors located both systemically and within the CNS.

Animals↗
PubMed1995

The social course of epilepsy: chronic illness as social experience in interior China.

Findings are reported from a collaborative research project on the experience of epilepsy and treatment among patients and family members in Shanxi and Ningxia Provinces in China. Family, marriage, financial and moral consequences of the social experience of epilepsy support the conceptualization of chronic illness as possessing a social course. Beyond traditional concern with stigma, application of concepts of delegitimation, sociosomatic processes, coping as resistance, contestation in the evaluation of efficacy and compliance, and the cultural ontology of suffering illustrate other ways that social theory is useful in research on chronic illness and disability.

Adaptation, Psychological↗
PubMed2004

A new set of BXD recombinant inbred lines from advanced intercross populations in mice.

BACKGROUND: Recombinant inbred (RI) strains are an important resource for mapping complex traits in many species. While large RI panels are available for Arabidopsis, maize, C. elegans, and Drosophila, mouse RI panels typically consist of fewer than 30 lines. This is a severe constraint on the power and precision of mapping efforts and greatly hampers analysis of epistatic interactions. RESULTS: In order to address these limitations and to provide the community with a more effective collaborative RI mapping panel we generated new BXD RI strains from two independent advanced intercrosses (AI) between C57BL/6J (B6) and DBA/2J (D2) progenitor strains. Progeny were intercrossed for 9 to 14 generations before initiating inbreeding, which is still ongoing for some strains. Since this AI base population is highly recombinant, the 46 advanced recombinant inbred (ARI) strains incorporate approximately twice as many recombinations as standard RI strains, a fraction of which are inevitably shared by descent. When combined with the existing BXD RI strains, the merged BXD strain set triples the number of previously available unique recombinations and quadruples the total number of recombinations in the BXD background. CONCLUSION: The combined BXD strain set is the largest mouse RI mapping panel. It is a powerful tool for collaborative analysis of quantitative traits and gene function that will be especially useful to study variation in transcriptome and proteome data sets under multiple environments. Additional strains also extend the value of the extensive phenotypic characterization of the previously available strains. A final advantage of expanding the BXD strain set is that both progenitors have been sequenced, and approximately 1.8 million SNPs have been characterized. This provides unprecedented power in screening candidate genes and can reduce the effective length of QTL intervals. It also makes it possible to reverse standard mapping strategies and to explore downstream effects of known sequence variants.

Animals↗
PubMed2006

SARS: how to manage future outbreaks?

Severe acute respiratory syndrome (SARS) was an unknown disease barely 3 years ago. After the World Health Organization declared the world SARS-free on 5 July 2003, there were episodic recurrences of SARS between September 2003 and May 2004, including 4 cases of laboratory-acquired SARS. SARS posed a mammoth challenge because of the impact of nosocomial transmission on healthcare manpower and facilities, and the resources needed for controlling and preventing further spread. Through worldwide scientific collaboration, the medical community has made much progress in unraveling its enigma, though much more needs to be discovered. This paper highlights how we can apply our knowledge of its epidemiology, mode of transmission, clinical course, ICU admission, complications, predictors of poor outcome, treatment and infection control to help us avert a catastrophic outbreak, and to manage our resources and patients. SARS preparedness and response planning must be flexible and dynamic so that appropriate measures can be implemented as an outbreak progresses. Even if SARS does not reemerge, the experience gained from such planning is valuable in preparing for threats of bioterrorism or a global avian influenza A (H5N1) virus pandemic.

Cross Infection↗
PubMed2005

Prospective evaluation of the four DSM-IV criteria for alcohol abuse in a large population.

OBJECTIVE: In 1994 DSM-IV presented new criteria for substance abuse as repetitive problems in any one of four areas reflecting social, interpersonal, and legal difficulties. The authors systematically evaluate the performance of each of the four diagnostic criteria for alcohol abuse (problems in role functioning, alcohol use in hazardous situations, alcohol-related legal problems, and social or interpersonal problems) and determine the prognosis associated with a threshold of one versus two or more criterion endorsements. METHOD: Baseline and 5-year follow-up data were analyzed for 2,596 men and women from the Collaborative Study on the Genetics of Alcoholism, including 1,881 individuals with no alcohol-related diagnosis, and 715 with alcohol abuse, after excluding subjects with alcohol dependence. Performance of each criterion was analyzed for the entire group and for the 565 individuals who endorsed only one criterion at baseline. RESULTS: One alcohol abuse criterion was endorsed by 79% of subjects with alcohol abuse, 18.5% endorsed two, and 2.5% endorsed three. Compared with subjects who endorsed no criteria, individuals who reported any of the four diagnostic criteria at baseline had higher rates of alcohol and drug intake and related problems and higher rates of future difficulties. Diagnostic thresholds of one versus two abuse criteria at baseline performed equally well regarding most outcomes, although endorsement of two criteria predicted a higher risk for progression to dependence. The criterion most frequently endorsed--hazardous use--was associated with baseline substance use characteristics and problematic outcomes similar to those for the other criteria. CONCLUSIONS: The four DSM-IV alcohol abuse criteria performed well regarding both cross-sectional characteristics and the prediction of future problems, but no single diagnostic criterion was superior to any other. The similarity of outcomes for subjects with diagnostic thresholds of one versus two or more criteria may favor the continued use of a threshold of one criterion in the diagnosis of alcohol abuse.

Adult↗
PubMed2004

The development and implementation of the National Comorbidity Survey Replication, the National Survey of American Life, and the National Latino and Asian American Survey.

This paper provides an overview of the development and implementation of the Collaborative Psychiatric Epidemiology Surveys (CPES): the National Comorbidity Survey Replication (NCS-R), the National Survey of American Life (NSAL), and the National Latino and Asian American Study (NLAAS). It describes the instrument development and testing phases, the development of training and other project materials, interviewer recruitment and training activities, and data collection procedures and outcomes. The last section offers recommendations for other researchers who undertake similar studies and who might benefit from the experiences learned in the development and operation of NCS-R, NSAL and NLAAS.

Adult↗
PubMed1996

Site-specific recombination by Tn3 resolvase, photocrosslinked to its supercoiled DNA substrate.

Site-specific recombination, transposition, and retroviral integration reactions involve the collaborative action of multiple identical protein subunits, making it difficult to determine the catalytic functions and fate of a subunit at any particular DNA binding site of the substrate. To investigate the mechanism of catalysis by the site-specific recombinase Tn3 resolvase, we fixed specific subunits to their binding sites by laser photocrosslinking, using a partially synthetic supercoiled DNA substrate containing photoreactive nucleotides. Crosslinked resolvase subunits were able to participate in a complete recombination reaction, demonstrating that the interaction of the subunit with its binding site persists throughout the reaction, and thus placing limitations on acceptable models for the catalytic mechanism.

Base Sequence↗
PubMed1986

Therapeutic embolization angiography for extra-axial lesions in the head.

Percutaneous transcatheter arterial embolization has played an increasingly important role in the management of vascular lesions in the head. Embolization can promote thrombosis within vascular tumors and malformations, reduce bleeding and decrease the need for transfusion intraoperatively, and facilitate surgical approaches to otherwise unresectable lesions. It is important for the clinician to be aware of this interventional technique because many of the patients who are considered for embolization are triaged through several different clinical areas, and much can be gained from the collaboration of the clinician, the surgeon, and the angiographer. We performed 31 therapeutic particulate embolization procedures for extra-axial head lesions in 23 patients by using flow-directed techniques. Of these procedures, 11 resulted in vascular occlusion and 15 resulted in 80 to 95% obstruction, as demonstrated by angiography. In 14 patients, embolization was performed preoperatively both to decrease blood loss and to occlude inaccessible or unresectable portions of a lesion. In nine patients, embolization was the sole means of treatment for occluding an abnormal vascular shunt. Two patients (9%) experienced a minor transient neurologic change after the procedure.

Adolescent↗
PubMed2003

First evidence for different freeze-out conditions for kaons and antikaons observed in heavy-ion collisions.

Differential production cross sections of K- and K+ mesons have been measured in Ni+Ni and Au+Au collisions at a beam energy of 1.5 A GeV. The K(-)/K(+) ratio is found to be nearly constant as a function of the collision centrality and system size. The spectral slopes and the polar emission pattern differ for K- and K+ mesons. These observations indicate that K+ mesons decouple earlier from the fireball than K- mesons.

Journal Article↗
PubMed2006

Signaling interactions between the aerotaxis transducer Aer and heterologous chemoreceptors in Escherichia coli.

Aer, a low-abundance signal transducer in Escherichia coli, mediates robust aerotactic behavior, possibly through interactions with methyl-accepting chemotaxis proteins (MCP). We obtained evidence for interactions between Aer and the high-abundance aspartate (Tar) and serine (Tsr) receptors. Aer molecules bearing a cysteine reporter diagnostic for trimer-of-dimer formation yielded cross-linking products upon treatment with a trifunctional maleimide reagent. Aer also formed mixed cross-linking products with a similarly marked Tar reporter. An Aer trimer contact mutation known to abolish trimer formation by MCPs eliminated Aer trimer and mixed trimer formation. Trimer contact alterations known to cause epistatic behavior in MCPs also produced epistatic properties in Aer. Amino acid replacements in the Tar trimer contact region suppressed an epistatic Aer signaling defect, consistent with compensatory conformational changes between directly interacting proteins. In cells lacking MCPs, Aer function required high-level expression, comparable to the aggregate number of receptors in a wild-type cell. Aer proteins with clockwise (CW)-biased signal output cannot function under these conditions but do so in the presence of MCPs, presumably through formation of mixed signaling teams. The Tar signaling domain was sufficient for functional rescue. Moreover, CW-biased lesions did not impair aerotactic signaling in a hybrid Aer-Tar transducer capable of adjusting its steady-state signal output via methylation-dependent sensory adaptation. Thus, MCPs most likely assist mutant Aer proteins to signal productively by forming collaborative signaling teams. Aer evidently evolved to operate collaboratively with high-abundance receptors but can also function without MCP assistance, provided that it can establish a suitable prestimulus swimming pattern.

Amino Acid Substitution↗
PubMedDate not supplied

Digital mammography: quality and dose control.

PURPOSE: For almost 3 years, Radiologists and Physicists from Padova and Ferrara Universities have collaborated together, with the aim of collecting and comparing experimental data useful to define the most significant parameters for quality controls in digital mammography. Successively, radiologists and physicists working in other sites where a digital mammography unit was installed joined the work-group. MATERIALS AND METHODS: In this study we report the results obtained from measurements of linearity, uniformity, short- and long-term reproducibility, AEC stability performed on 5 digital equipment by using a simple test object. X-ray beam quality and tube yield were preliminarily checked in such a way that possible uncertainties of digital system responses could be separated from those due to differences among X-ray tubes. RESULTS: Results showed that the equipment considered, comparable in terms of both beam quality (HVL) and tube yield, always displayed linear response and reproducibility errors lower than 5%. Uniformity was very good and the grey level compensation as a function of exposure parameters remained within 5%. Differences in choice of parameters by exposure control system (AOP) were emphasised, especially for crossing between track/filter combinations (from Mo/Mo to Mo/Rh and from Mo/Rh to Rh/Rh); those differences were attributed to the +/-2 mm tolerance of breast thickness measurement (mechanically obtained) greater than the AOP tolerance (+/-1 mm). DISCUSSION AND CONCLUSIONS: Obtained results can be useful, as comparison and reference values, for users employing a digital mammography unit of the same kind reported in this paper. Moreover, the same results could be used as "orientation" also by other users having different digital mammography technologies, whose operation should be nevertheless specifically studied and understood in order to find the most useful parameters for quality controls. The acquired experience clearly showed us that years of investigations will be necessary in order to be able to write reliable protocols. This should induce people to contemplate the necessity of not improvising "theoretical" protocols, that are unreliable and dangerous for their negative clinical implications.

Humans↗
PubMed2002

Thyroid diseases in pregnancy.

INTRODUCTION: Changes in thyroid function in pregnancy encompass both hyper- and hypothyroidism. Failure to maintain euthyroidism may place both mother and foetus at higher risk of adverse obstetrical outcomes. This review examines the differences between physiological and pathological thyroid dysfunction during pregnancy and their management. METHODS: Data were obtained from relevant clinical studies and review articles listed in MEDLINE. Additional cross-references from selected articles were identified. RESULTS: In hyperthyroidism, the challenge lies in differentiating gestational transient thyrotoxicosis (GTT) from actual pathological states during the first trimester. GTT is thought to be due to elevation of isoforms of human chorionic gonadotropin (hCG) which may exert potent thyrotrophic effects. While thionamides are safe, the lowest possible dose should be used together with close monitoring of maternal thyroid function in order to avoid over-treatment. Surgery for thyroid nodules may be safely performed during the second trimester. Conversely, diagnosing hypothyroid states, particularly subclinical hypothyroidism and postpartum thyroiditis (PPT), require a high index of suspicion. High levels of thyroid peroxidase antibodies (TPOAb) and thyroid stimulating hormone (TSH) in early pregnancy may be predictive of PPT and subsequent permanent hypothyroidism. Clinicians must recognise the need to increase thyroxine replacement as maternal hypothyroidism may adversely affect the IQ scores of children. The association between thyroid autoimmunity and recurrent abortions remain unclear. CONCLUSION: Regardless of the aetiology of thyroid dysfunction, the key to management lies in individualized therapy in close collaboration with the obstetrician.

Antibodies↗