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PubMed1978

The concept of a 'case' in psychiatric population surveys.

A series of in-patients, a series of out-patients and a series of women from a general population sample, all aged under 65, and all living in the same area of south-east London, were examined using the ninth edition of the Present State Examination (PSE). An 'index of definition' (ID), based on number, type and severity of PSE symptoms, was constructed in order to define a threshold point above which sufficient information was available to allow classification into one of the functional psychoses or neuroses. The index specified 8 levels of definition of disorder; the threshold point for a 'case' lying between levels 4 and 5. The identification of 'cases' by this means in the general population series was highly concordant with global clinical judgement. When the 3 series were compared, the in-patient series contained the most definite cases, the outpatient series was intermediate, and the general population series was characterized mainly by below-threshold conditions. Disorders above the threshold point were classified using the CATEGO program. The clinical severity of the depressive disorders and anxiety states identified in this way in the 3 series was compared on the basis of symptom and syndrome profiles and PSE scores. As expected, the inpatients had the most severe, and the general population 'cases' the least severe disorders. It is suggested that the PSE-ID-CATEGO techniques can be used to help standardize certain aspects of case-finding and case-description in both referred and non-referred populations and thereby make the results of surveys more comparable.

Adolescent↗
PubMed2001

Emotional reactivity and risk for psychopathology among adolescents.

Various aspects of personality or dispositional style predict risk for psychiatric disorders among adults. In particular, signs of neuroticism, emotional reactivity, or sensitivity to stress are strong predictors of later mood or anxiety disorders. The current report extends this literature to adolescents. An epidemiologic sample of 776 young people living in upstate New York received psychiatric assessments based on the Diagnostic and Statistical Manual of Mental Disorders, Third Edition-Revised, (DSM-III-R) and a self-report assessment of personality style in 1983 and 1985. Psychopathology was again assessed in 1992. The current study first examined demographic correlates of emotional reactivity. The study then considered the predictive relationship between emotionally reactive personality style at one study wave and psychopathology at later waves. In middle but not early adolescence, girls showed higher levels of emotional reactivity than boys. In turn, high levels of emotional reactivity predicted a range of psychiatric disorders at follow-up. The most consistent associations emerged for major depression and fearful spells, a term the authors use to describe a subclinical form of panic attacks. As in adults, midadolescent girls rate themselves as more emotionally reactive than midadolescent boys. Moreover, adolescents who rate themselves as emotionally reactive face a high risk for mood and anxiety disorders. High levels of emotional reactivity may represent a manifestation of underlying neurobiologic risk for mood and anxiety disorders.

Journal Article↗
PubMed1997

Occurrence of plastid RNA editing in all major lineages of land plants.

RNA editing changes posttranscriptionally single nucleotides in chloroplast-encoded transcripts. Although much work has been done on mechanistic and functional aspects of plastid editing, little is known about evolutionary aspects of this RNA processing step. To gain a better understanding of the evolution of RNA editing in plastids, we have investigated the editing patterns in ndhB and rbcL transcripts from various species comprising all major groups of land plants. Our results indicate that RNA editing occurs in plastids of bryophytes, fern allies, true ferns, gymnosperms, and angiosperms. Both editing frequencies and editing patterns show a remarkable degree of interspecies variation. Furthermore, we have found that neither plastid editing frequencies nor the editing pattern of a specific transcript correlate with the phylogenetic tree of the plant kingdom. The poor evolutionary conservation of editing sites among closely related species as well as the occurrence of single species-specific editing sites suggest that the differences in the editing patterns and editing frequencies are probably due both to independent loss and to gain of editing sites. In addition, our results indicate that RNA editing is a relatively ancient process that probably predates the evolution of land plants. This supposition is in good agreement with the phylogenetic data obtained for plant mitochondrial RNA editing, thus providing additional evidence for common evolutionary roots of the two plant organellar editing systems.

Amino Acid Sequence↗
PubMed2000

End processing precedes mitochondrial importation and editing of tRNAs in Leishmania tarentolae.

All mitochondrial tRNAs in Leishmania tarentolae are encoded in the nuclear genome and imported into the mitochondrion from the cytosol. One imported tRNA (tRNA(Trp)) is edited by a C to U modification at the first position of the anticodon. To determine the in vivo substrates for mitochondrial tRNA importation as well as tRNA editing, we examined the subcellular localization and extent of 5'- and 3'-end maturation of tRNA(Trp)(CCA), tRNA(Ile)(UAU), tRNA(Gln)(CUG), tRNA(Lys)(UUU), and tRNA(Val)(CAC). Nuclear, cytosolic, and mitochondrial fractions were obtained with little cross-contamination, as determined by Northern analysis of specific marker RNAs. tRNA(Gln) was mainly cytosolic in localization; tRNA(Ile) and tRNA(Lys) were mainly mitochondrial; and tRNA(Trp) and tRNA(Val) were shared between the two compartments. 5'- and 3'-extended precursors of all five tRNAs were present only in the nuclear fraction, suggesting that the mature tRNAs represent the in vivo substrates for importation into the mitochondrion. Consistent with this model, T7-transcribed mature tRNA(Ile) underwent importation in vitro into isolated mitochondria more efficiently than 5'-extended precursor tRNA(Ile). 5'-Extended precursor tRNA(Trp) was found to be unedited, which is consistent with a mitochondrial localization of this editing reaction. T7-transcribed unedited tRNA(Trp) was imported in vitro more efficiently than edited tRNA(Trp), suggesting the presence of importation determinants in the anticodon.

Animals↗
PubMedDate not supplied

Assessing the direct costs of treating nonvalvular atrial fibrillation in the United States.

OBJECTIVE: To determine the health-care resource use and costs attributable to treating atrial fibrillation (AF) in the United States. METHODS: Retrospective analyses of three federally funded US databases (2001 data): 1) hospital inpatient stays (the Healthcare Cost and Utilization Project [HCUP]); 2) physician office visits (the National Ambulatory Medical Care Survey [NAMCS]); and 3) emergency department (ED) and hospital outpatient department visits (OPD) (the National Hospital Ambulatory Medical Care Survey [NHAMCS]). Identification of AF medical encounters was based on occurrence of AF-specific International Classification of Diseases (9th Edition)--Clinical Modification (ICD-9-CM) diagnosis code 427.31 (principal discharge diagnosis for inpatient setting; any diagnosis field for other settings). For the 10 most common principal discharge diagnoses in the inpatient setting, case-control comparison analyses were performed to estimate annual incremental costs of AF as a comorbid discharge diagnosis for hospital stays. Regression models were used to assess the impact of AF on hospitalization costs. Costs were estimated in year 2005 US dollars. RESULTS: Approximately 350,000 hospitalizations, 5.0 million office visits, 276,000 ED visits, and 234,000 OPD were attributable to AF annually within the United States. Total annual costs for treatment of AF were estimated at $6.65 billion, including $2.93 billion (44%) for hospitalizations with a principal discharge diagnosis of AF, $1.95 billion (29%) for the incremental inpatient cost of AF as a comorbid diagnosis, $1.53 billion (23%) for outpatient treatment of AF, and $235 million (4%) for prescription drugs. In all regressions, AF was a significant contributor to hospital cost. CONCLUSIONS: Treatment of AF represents a significant health-care burden with the costs of treating AF in the inpatient setting outweighing the costs of treating AF in the office, emergency room or hospital outpatient settings. Further research is needed to fully capture the costs of treating AF.

Aged↗
PubMed2004

An investigative laboratory course in human physiology using computer technology and collaborative writing.

Active investigative student-directed experiences in laboratory science are being encouraged by national science organizations. A growing body of evidence from classroom assessment supports their effectiveness. This study describes four years of implementation and assessment of an investigative laboratory course in human physiology for 65 second-year students in sports medicine and biology at a small private comprehensive college. The course builds on skills and abilities first introduced in an introductory investigations course and introduces additional higher-level skills and more complex human experimental models. In four multiweek experimental modules, involving neuromuscular, reflex, and cardiovascular physiology, by use of computerized hardware/software with a variety of transducers, students carry out self-designed experiments with human subjects and perform data collection and analysis, collaborative writing, and peer editing. In assessments, including standard course evaluations and the Salgains Web-based evaluation, student responses to this approach are enthusiastic, and gains in their skills and abilities are evident in their comments and in improved performance.

Computer-Assisted Instruction↗
PubMed2004

Extracellular and circulating redox- and metalloregulated eRNA and eRNP: copper ion-structured RNA cytokines (angiotropin ribokines) and bioaptamer targets imparting RNA chaperone and novel biofunctions to S100-EF-hand and disease-associated proteins.

Bioassays for cellular differentiation and tissue morphogenesis were used to design methods for isolation of bioactive redox- and metalloregulated nucleic acids and copper ion complexes with proteins from extracellular, circulating, wound, and supernatant fluids of cultured cells. In extracellular biospheres, diversities of nucleic acids were found to be secreted by cells upon activation. They may reflect nucleic acid biolibraries with molecular imprints of cellular history. After removal of protein components, eRNA prototypes exuded by activated cells were sequenced. They are small, endogenous, highly modified and edited, redox- and metalloregulated 5'-end phosphorylated extracellular eRNA (approximately 2-200 bases) with cellular, enzymic, and bioaptamer functions. Fenton-type OH* radical redox reactions may form modified nucleotides in RNA as wobbles eRNA per se, or as copper ion-complex with protein (e.g., S100A12-EF-hand protein, angiotropin-related protein, calgranulin-C, hippocampal neurite differentiation factor) are shown to be bioactive in vivo and in vitro as cytokines (ribokines) and as nonmitogenic angiomorphogens for endothelial cell differentiation in the formation of organoid supracellular capillary structures. As bioaptamers, copper ion-structured eRNA imparts novel biofunctions to proteins that they do not have on their own. The origin of extracellular RNA and intermediate precursors (up to 500 bases) was traced to intracellular parent nucleic acids. Intermediate precursors with and without partial homology were found. This suggests that bioaptamers are not directly retranslatable gene products. Metalloregulated eRNA bioaptamer function was investigated by domains (e.g. 5'...CUG...3' hairpin loop) for folding, bioactivity, and binding of protein with copper, calcium, and alkali metal ion affinity. Vice versa, metalloregulated nucleic acid-binding domains (K3H, R3H) in proteins were identified. Interaction of protein and eRNA docking potentials were visualized by 3D-rapid prototyping of accurate molecular image models based on crystallographic or NMR data. For S100A12-homologous proteins, receptor- and metalloregulated RNA chaperone-shaped protein assemblies were investigated. They suggest insight into signaling cascades as to how eRNA transmits its cytokine (ribokine) bioinformation from the extracellular RNA biosphere into cells. Proteomics of the extracellular RNA biosphere demonstrate the presence of nucleic acid-binding domain homologies in defense-, aging-, and disease-associated neuronal and other proteins as targets for RNA orphans. By structural relationships found to transmissible processes, proteinaceous transfer ("infectivity") and feedback of bioinformation beyond the central dogma of molecular biology are considered in terms of metalloregulated RNA bioaptamer function, nucleic acid-binding domains, and protein conformation.

Amino Acid Sequence↗
PubMed2004

DairyBeef: maximizing quality and profits--a consistent food safety message.

To respond to meat safety and quality issues in dairy market cattle, a collaborative project team for 7 western states was established to develop educational resources providing a consistent meat safety and quality message to dairy producers, farm advisors, and veterinarians. The team produced an educational website and CD-ROM course that included videos, narrated slide sets, and on-farm tools. The objectives of this course were: 1) to help producers and their advisors understand market cattle food safety and quality issues, 2) help maintain markets for these cows, and 3) help producers identify ways to improve the quality of dairy cattle going to slaughter. DairyBeef. Maximizing Quality & Profits consists of 6 sections, including 4 core segments. Successful completion of quizzes following each core segment is required for participants to receive a certificate of completion. A formative evaluation of the program revealed the necessity for minor content and technological changes with the web-based course. All evaluators considered the materials relevant to dairy producers. After editing, course availability was enabled in February, 2003. Between February and May, 2003, 21 individuals received certificates of completion.

Animals↗
PubMed2026

Herbicide Resistance Genes in Crops: Mechanisms, Progress, and Future Perspectives.

While previous reviews have largely focused on individual crops or single target-site mechanisms, the full-chain comparative landscape across major cereal crops remains unexplored. Here, we fill this critical gap by providing the first systematic, cross-crop comparative review that spans herbicide targets, resistance mechanisms, and breeding applications across four major cereals-rice, maize, wheat, and sorghum. Weed infestation is a serious constraint on crop production. Chemical weed control faces challenges such as herbicide resistance evolution and ecological risks. Developing herbicide-resistant varieties is a fundamental approach to achieve green and sustainable weed management. This review systematically summarizes research progress on herbicide resistance genes from three aspects: herbicide classification, resistance mechanisms, and crop breeding applications. It highlights key differences among four major cereal crops (rice, maize, wheat, and sorghum) in resistance-gene discovery and translational progress. Rice has the richest target-site resistance-gene resources. Maize leads in commercialization of transgenic herbicide resistance. Wheat focuses on endogenous precise editing due to genome complexity and regulatory constraints. Sorghum relies on specific mutations to serve cereal-legume intercropping systems. Based on this comparison, this review identifies the core trends in resistance breeding: from single-gene to multi-gene stacking, and from exogenous gene introduction to endogenous gene editing. It also points out common bottlenecks, including insufficient systematic mining of resistance-gene resources, lagging elucidation of non-target-site resistance regulatory networks, and strong genotype dependence in genetic transformation. Future efforts should focus on exploring broad-spectrum resistance genes, optimizing precise editing technologies, and developing sustainable resistance management strategies. This review provides a theoretical framework and practical references for molecular breeding of herbicide-resistant crops.

crop breeding↗
PubMed2026

Genetic Deletion of Cis-Regulatory Elements to Dissect the Function of the Non-coding Genome in human Preimplantation Models.

Cis-regulatory elements coordinate gene expression in a spatially and temporally controlled manner and contribute to the establishment of distinct cellular states during development. A substantial proportion of transcriptionally active cis-regulatory elements in primate embryos originated from ancient retroviral integrations into the germline. These endogenous retroviruses, also known as long terminal repeat retrotransposons, retain intrinsic regulatory activity and are often species-specific, making them strong candidates for regulating species-divergent aspects of embryonic development. Ethical and legal restrictions on human embryo research have historically limited direct investigation of gene regulation during human embryogenesis. Human naive pluripotent stem cells and three-dimensional stem cell-based blastocyst models provide alternative systems for studying early developmental processes. This protocol describes the CRISPR-Cas9-mediated deletion of endogenous retrovirus-derived cis-regulatory elements in human naive pluripotent stem cells. Preassembled Cas9 and single-guide RNA ribonucleoprotein complexes are delivered by nucleofection, followed by single-cell cloning, PCR-based genotyping, Sanger sequencing, expansion, cryopreservation, and genomic stability assessment of the edited lines. The resulting wild-type, heterozygous, and homozygous or hemizygous deletion clones provide a platform for investigating the contribution of individual endogenous retrovirus-derived elements to gene regulation in human preimplantation models. This method enables direct functional interrogation of species-specific non-coding regulatory sequences and supports the study of transcriptional mechanisms involved in early human development.

Humans↗
PubMed1985

Domain specifications of the construct tactile defensiveness.

A comprehensive list of descriptors of behaviors associated with tactile defensiveness in elementary schoolchildren was compiled as a preliminary to subsequent psychometric measurement of tactile defensiveness. This, the first phase of scale development, was accomplished in the following manner. The construct tactile defensiveness was defined, and a variety of behaviors related to the domain of the construct were collected. The list of behaviors was submitted to an expert for review. Descriptors of statements a child might make based on the behaviors were generated. Then, the list of descriptors was edited, and the remaining descriptors were rated by a panel of experts according to the degree to which the descriptor was associated with tactile defensiveness. Logical and computer analyses of the descriptors' ratings were performed. Of the 73 descriptors specified, two were dropped because of cultural bias and 24 were dropped because they were not rated by the experts as being associated with tactile defensiveness. This paper discusses the importance of the remaining list of 47 descriptors for subsequent research and delineates appropriate clinical use of those descriptors.

Child↗
PubMed2005

Attention deficit and hyperactivity disorder among school children in Kinshasa, Democratic Republic of Congo.

OBJECTIVES: To estimate the prevalence and determinants of attention deficit and hyperactivity disorder (ADHD) symptoms among school children in Kinshasa, an African urban setting. METHODS: The 18-items of the Disruptive Behaviour Disorder rating scale (DBD), which is based on the Diagnostic and Statistical Manual for mental disorders 4(th) edition (DSM-IV), were used to investigate the presence of ADHD symptoms. Parents interviews, using a questionnaire specially designed for the study, were performed to identify socio-demographic characteristics. All children were subject to a clinical examination. RESULTS: The estimated prevalence of DSM-IV ADHD symptoms was 6%. Those with family health problems, younger age at start of primary school, good nutritional status and poor school performance more often had DSM-IV ADHD symptoms. CONCLUSION: ADHD symptoms are as common among school children in Kinshasa as elsewhere. The socio-demographic factors described as risk factors for ADHD in high-income countries were not identified in this study.

Attention Deficit Disorder with Hyperactivity↗
PubMed2004

A collaborative clinical trial protocol writing system.

Increasing complexity in medicine has caused clinical trial experts with disparate backgrounds from multiple organizations to collaborate when developing clinical trial protocols. Although many protocol-authoring tools provide computerbased decision support to assist in protocol writing, few of them provide sufficient collaboration support for a group of protocol writers. The iterative group writing activities among interdisciplinary clinical trial experts call for advanced tool support. Here we present a web-based protocol writing system with integrated support for collaborative reviewing and collaborative editing. The system uses a shared database to store threaded review comments and version information for electronic protocols. It also captures rich group event information to provide cross-activity awareness and to facilitate self-coordination within the collaborative writing team. We believe that our system can help streamline collaborative clinical trial protocol writing processes.

Clinical Protocols↗
PubMed1995

Detecting delirium among hospitalized older patients.

BACKGROUND: Delirium occurs commonly among older hospitalized patients and is frequently not recognized. In an effort to identify tools useful to clinicians in the diagnosis of delirium, test characteristics of four screening instruments were compared. METHODS: Patients 65 years of age or older who were admitted to one of four medical and surgical wards of a university teaching hospital were followed up prospectively. Potential subjects were excluded if unavailable for interviews or discharged within 48 hours of admission, or if judged too impaired to participate in the daily interviews. Research assistants administered four instruments used to detect delirium: Digit Span Test, Vigilance 'A' Test, Clinical Assessment of Confusion, and Confusion Assessment Method. Abnormal scores on these tests or suspicion of acute confusion prompted a referral to the clinician-investigators who then assessed the patient daily for delirium based on the Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition criteria. RESULTS: Delirium occurred in 64 (14.8%) of 432 subjects. The positive likelihood ratios for all of the instruments were significantly more than 1. The instruments remained useful when applied to selected subgroups: subjects in whom acute mental status changes were documented, subjects on surgical services, and subjects with impaired cognitive status on admission. Combinations of any two instruments did not perform substantially better than the instrument with the best test characteristics: the Clinical Assessment of Confusion. All instruments were more useful at confirming delirium than in excluding it. CONCLUSION: The four instruments studied, which are suitable for use at the bedside, can aid the clinician in identifying patients likely to be suffering from delirium.

Aged↗
PubMed1996

The present status of hyperthermia in Japan.

The research on hyperthermia in Japan was started by the Hyperthermia Study Group in 1978. Six years later, in 1984, the Japanese Society of Hyperthermic Oncology (JSHO) was established. More and more research has been conducted since then. At present, 215 units of heating equipment are installed for use. Among these, 24% are microwave heating equipment, and 66% are radiofrequency (RF) capacitive heating equipment. A nation-wide survey has revealed that about 60% of hyperthermia therapy involves the treatment of deep-seated tumours by RF capacitive heating and RF intracavitary heating. The treatment of superficial tumours by microwave heating represents another 12.5%. Most of the clinical application in the United States and in Europe is microwave heating of superficial tumours. The different modalities of treatment were thermoradiotherapy in 57.5%, thermochemotherapy in 22.6% and thermochemoradiotherapy in 14.5% of the cases surveyed. Compared to other countries, Japan has the highest number of hyperthermia equipment installed, and the most doctors involved in hyperthermia therapy. The main reasons for the advanced state of hyperthermia research in Japan include the development of excellent heating equipment, high membership in JSHO, grant-in-aid by the Japanese government, and coverage by insurance for this form of therapy. Based on 33 papers selected from two books which the author had edited, the optimal protocol, effectiveness and indication for the use of hyperthermia has been established.

Combined Modality Therapy↗
PubMed1996

[How to assess the value of scientific publications?].

The Institute of Scientific Information has edited an index to evaluate the diffusion of scientific articles. It is based on the fact that the more an article is cited as a reference in other articles, the more it is considered to be important, and the higher the coefficient attributed to the journal in which it was originally published. Several methods of evaluation have been proposed, the two main ones being the impact and citation half-life. The impact factor takes into account the average number of times which a journal is mentioned for recent articles published in a given year. The citation half-life gives an insight into the longeivity of the articles of a journal by the number of citations received. This index is an attempt to quantify the notoriety of scientific journals for all scientific medical specialties. Each year, the institute for Scientific Information publishes a classification of the journals of each medical specialty.

Bibliometrics↗
PubMed1998

[Bibliometric index].

The Institute of Scientific information has edited an index to evaluate the diffusion of scientific articles. It is based on the fact that the more an article is cited as a reference in other articles, the more it is considered to be important, and the higher the coefficient attributed to the journal in which it was originally published. The impact factor takes into account the average number of times which a journal is mentioned for recent articles published in a given year. This index is an attempt to quantify the notoriety of scientific journal for all scientific medical specialties.

Bibliometrics↗