Contributing factors identified by hospital incident report narratives.

CONTEXT: A major purpose of incident reporting is to understand contributing factors so that causes of errors can be uncovered and systems made safer. For established reporting systems in US hospitals, little is known about how well the reports identify contributing factors. OBJECTIVE: To characterise the information incident report narratives provide about contributing factors using a taxonomy we developed for this purpose. DESIGN: Descriptive study examining 2228 reports for 16 575 randomly selected patients discharged from an academic and a community hospital in the US between 1 January and 31 December 2001. MAIN OUTCOMES MEASURED: Reports in which patient, system and provider (errors, mistakes and violations) factors were identifiable. RESULTS: 80% of reports described at least one contributing factor. Patient factors were identifiable in 32%, most frequently illness (61% of these reports) and behaviour (24%). System factors were identifiable in 32%, most commonly equipment malfunction or difficulty of use (38%), problems coordinating care among providers (31%), provider unavailability (24%) and tasks that were difficult to execute correctly (20%). Provider factors were evident in 46%, but half of these reports contained insufficient detail to determine which specific factor. When detail sufficed, slips (52%), exceptional violations (22%), lapses (15%) and applying incorrect rules (13%) were common. CONCLUSIONS: Contributing factors could be identified in most incident-report narratives from these hospitals. However, each category of factors was present in a minority of reports, and provider factors were often insufficently elucidated. Greater detail about contributing factors would make incident reports more useful for improving patient safety.

A national survey of care for persons with co-occurring mental and substance use disorders.

OBJECTIVE: The delivery of appropriate treatment to persons who have mental and substance use disorders is of increasing concern to clinicians, administrators, and policy makers. This study sought to describe use of appropriate mental health and comprehensive substance abuse care among adults in the United States with probable co-occurring disorders. METHODS: Data from the Healthcare for Communities survey, which is based on a national household sample studied in 1997 and 1998, were used to identify individuals who had probable co-occurring mental and substance use disorders. The sociodemographic and clinical characteristics of these individuals and their use of services were recorded. Logistic regression analysis was used to identify variables associated with receipt of mental health and substance abuse treatment and with receipt of appropriate treatment. RESULTS: Estimates for the U.S. adult population based on the weighted survey data indicated that 3 percent of the population had co-occurring disorders. Seventy-two percent did not receive any specialty mental health or substance abuse treatment in the previous 12 months; only 8 percent received both specialty mental health care and specialty substance abuse treatment. Only 23 percent received appropriate mental health care, and 9 percent received supplemental substance abuse treatment. Perceived need for treatment was strongly associated with receipt of any mental health care and with receipt of appropriate care. CONCLUSIONS: Despite the availability of effective treatments, most individuals who had co-occurring mental health and substance use problems were not receiving effective treatment. Efforts to improve the care provided to persons who have co-occurring disorders should focus on strategies that increase the delivery of effective treatment.

Association of Vpu-binding protein with microtubules and Vpu-dependent redistribution of HIV-1 Gag protein.

The efficient exit of HIV-1 particles from cells requires the action of the viral encoded protein Vpu. Vpu-binding protein (Ubp) is a cellular protein that interacts with both Vpu and the major structural component of the viral capsid (Gag) and appears to affect the efficiency of particle exit. Elucidation of the function of Ubp and characterization of the spatial distribution of Ubp may provide information pertinent to understanding the role of Ubp in virus replication. To investigate the subcellular location of Ubp, and to see whether Vpu affects the intracellular distribution of Gag, we carried out immunofluorescence localization in conjunction with confocal microscopy. Based on this analysis Ubp is present in both the nucleus and the cytoplasm. In the cytoplasm, Ubp appeared to be associated with microtubules as evidenced by cofluorescence with tubulin in the absence and in the presence of colchicine. However, cytoskeletal isolation and detergent extraction of cells resulted in association of Ubp with the soluble fractions, indicating that Ubp is not in tight association with microtubules. Moreover, flotation gradient analysis demonstrated that Ubp is cytoplasmic and not stably associated with the plasma membrane. Interestingly, expression of Vpu in cells resulted in redistribution of both Ubp and Gag to a location near the periphery of the cell. The effect of Vpu on both Ubp and Gag protein has implications for Vpu-mediated particle exit from cells.

Principles and practices of laser scanning confocal microscopy.

The laser scanning confocal microscope (LSCM) is an essential tool for many biomedical imaging applications at the level of the light microscope. The basic principles of confocal microscopy and the evolution of the LSCM into today's sophisticated instruments are outlined. The major imaging modes of the LSCM are introduced including single optical sections, multiple wavelength images, three-dimensional reconstructions, and living cell and tissue sequences. Practical aspects of specimen preparation, image collection, and image presentation are included along with a primer on troubleshooting the LSCM for the novice.

Confocal laser scanning microscopy.

Many technological advancements of the past decade have contributed to improvements in the photon efficiency of the confocal laser scanning microscope (CLSM). The resolution of images from the new generation of CLSMs is approaching that achieved by the microscope itself because of continued development in digital imaging methods, laser technology and the availability of brighter and more photostable fluorescent probes. Such advances have made possible novel experimental approaches for multiple label fluorescence, live cell imaging and multidimensional microscopy.

Expression pattern of a butterfly achaete-scute homolog reveals the homology of butterfly wing scales and insect sensory bristles.

BACKGROUND: Lepidopteran wing scales are the individual units of wing color patterns and were a key innovation during Lepidopteran evolution. On the basis of developmental and morphological evidence, it has been proposed that the sensory bristles of the insect peripheral nervous system and the wing scales of Lepidoptera are homologous structures. In order to determine if the developmental pathways leading to Drosophila sensory bristle and butterfly scale formation use similar genetic circuitry, we cloned, from the butterfly Precis coenia, a homolog of the Drosophila achaete-scute (AS-C) genes--which encode transcription factors that promote neural precursor formation--and examined its expression pattern during development. RESULTS: During embryonic and larval development, the expression pattern of the AS-C homolog, ASH1, forecasted neural precursor formation. ASH1 was expressed both in embryonic proneural clusters--within which an individual cell retained ASH1 expression, enlarged, segregated, and became a neural precursor--and in larval wing discs in putative sensory mother cells. ASH1 was also expressed in pupal wings, however, in evenly spaced rows of enlarged cells that had segregated from the underlying epidermis but, rather than give rise to neural structures, each cell contributed to an individual scale. CONCLUSIONS: ASH1 appears to perform multiple functions throughout butterfly development, apparently promoting the initial events of selection and formation of both neural and scale precursor cells. The similarity in the cellular and molecular processes of scale and neural precursor formation suggests that the spatial regulation of an AS-C gene was modified during Lepidopteran evolution to promote scale cell formation.

Membrane potential mediates H(+)-ATPase dependence of "degradative pathway" endosomal fusion.

In some epithelial cell lines, the uptake and degradation of proteins is so pronounced as to be regarded as a specialized function known as "degradative endocytosis." The endosomal pathways of the renal proximal tubule and the visceral yolk sac share highly specialized structures for "degradative endocytosis." These endosomal pathways also have a unique distribution of their H(+)-ATPase, predominantly in the subapical endosomal pathway. Previous studies provide only indirect evidence that H(+)-ATPases participate in endosomal fusion events: formation of vesicular intermediates between early and late endosomes is H(+)-ATPase dependent in baby hamster kidney cells, and H(+)-ATPase subunits bind fusion complex proteins in detergent extracts of fresh rat brain. To determine directly whether homotypic endosomal fusion is H(+)-ATPase dependent, we inhibited v-type H(+)-ATPase during flow cytometry and cuvette-based fusion assays reconstituting endosomal fusion in vitro. We report that homotypic fusion in subapical endosomes derived from rat renal cortex, and immortalized visceral yolk sac cells in culture, is inhibited by the v-type H(+)-ATPase specific inhibitor bafilomycin A1. Inhibition of fusion by H(+)-ATPase is mediated by the membrane potential as collapsing the pH gradient with nigericin had no effect on homotypic endosomal fusion, while collapsing the membrane potential with valinomycin inhibited endosomal fusion. Utilizing an in vitro reconstitution assay this data provides the first direct evidence for a role of v-type H(+)-ATPase in mammalian homotypic endosomal fusion.

Testing for the BRCA1 and BRCA2 breast-ovarian cancer susceptibility genes: a decision analysis.

OBJECTIVE: The authors developed a Markov decision model to evaluate the health implications of testing for mutations in the BRCA1 and BRCA2 breast-ovarian cancer susceptibility genes. Prophylactic measures considered included various combinations of immediate and delayed bilateral mastectomy and oophorectomy or taking no action. METHODS: The model incorporated the likelihood of developing breast and/or ovarian cancer, survival, and quality of life. Parameter values were taken from public databases, the published literature, and a survey of cancer experts. Outcomes considered were additional life expectancy and quality-adjusted life years (QALYs). Results are reported for 30-year-old cancer-free women at various levels of hereditary risk. RESULTS AND CONCLUSIONS: The vast majority of women will not benefit from testing because their pre-test risks are low and surgical prophylaxis is undesirable. However, women who have family histories of early breast and/or ovarian cancer may gain up to 2 QALYs by allowing genetic testing to inform their decisions.

Imaging techniques: picture the world with kaleidoscope dyes.

Advances in fluorescence light microscopy have facilitated the production of images from multiply labeled specimens.

Methods and applications of three-color confocal imaging.

A simple method for constructing two- and three-color merged images from grayscale confocal fluorescence images using Adobe Photoshop is outlined. Various computer methods for manipulating and displaying the images are discussed in light of several recent biomedical applications of multi-label confocal microscopy.

Further developments of the laser scanning confocal microscope in biomedical research.

The laser scanning confocal microscope (LSCM) is a valuable research tool for imaging fluorescently labeled biological specimens. Rather than cutting sections of the tissue with a knife, it is now possible to produce relatively noninvasive "optical sections" using the LSCM as an imaging tool. This has made the imaging of living cells in situ more of a practical option. This minireview briefly describes some of the improvements made to the LSCM over the past 5 years and, in more detail, outlines many of the current biomedical applications of the LSCM, including single and multiple labeling of fixed and living specimens, physiological imaging, 3-dimensional imaging, and the use of the LSCM for lineage tracing and in correlative microscopy.

daughterless is required for Drosophila photoreceptor cell determination, eye morphogenesis, and cell cycle progression.

Initiation of Drosophila peripheral nervous system (PNS) development requires the achaete-scute complex (AS-C) and the atonal (ato) genes. The AS-C and ato encode basic helix-loop-helix (bHLH) transcription factors that dimerize in vitro with another bHLH protein, daughterless (da). da has many functions during Drosophila embryonic development, as it is required for proper sex determination, oogenesis, and neurogenesis. Here, we examine the expression and function of da within the developing Drosophila eye. The use of a monoclonal antibody to the Da protein revealed that Da levels are modulated across the developing eye disc. Within the morphogenetic furrow (MF) and photoreceptor cell R8, there is a cell-by-cell correspondence between high levels of Da protein expression and Ato protein expression. Mosaic analysis of adult tissue demonstrates that da function is cell autonomous and required within R2, R3, R4, R5, and R8. Examination of gene expression in da- imaginal disc clones reveals that da regulates Ato expression in the MF, affects the progression of the MF, and is necessary for the reestablishment of the G2 and M phases of the synchronized cell cycle posterior to the MF.

Hairy and emc negatively regulate morphogenetic furrow progression in the Drosophila eye.

The initial steps of pattern formation in the developing Drosophila eye involve the coordination of cell cycles, changes in cell shape, and the specification of the R8 photoreceptor cell. These events begin several cell rows ahead of the morphogenetic furrow and are positively regulated by secreted signaling proteins and the proneural HLH transcription factor atonal (ato). Two HLH regulatory proteins that function to suppress neuronal development in other tissues, extra macrochaetae (emc) and hairy (h), are expressed ahead of the morphogenetic furrow. While neither h nor emc is required for photoreceptor cell determination, in emc-h-clones the morphogenetic furrow and differentiated eye field advance up to eight ommatidial rows ahead of adjacent wild-type tissue. This indicates that morphogenetic furrow progression and neuronal differentiation are negatively regulated by a combination of anteriorly expressed HLH regulatory proteins.

Image manipulation. Confocal images to go?

Biologists are no longer restricted to using a single algorithm in their manipulation and display of data acquired using confocal microscopy.

Pattern formation and eyespot determination in butterfly wings.

Butterfly wings display pattern elements of many types and colors. To identify the molecular processes underlying the generation of these patterns, several butterfly cognates of Drosophila appendage patterning genes have been cloned and their expression patterns have been analyzed. Butterfly wing patterns are organized by two spatial coordinate systems. One system specifies positional information with respect to the entire wing field and is conserved between fruit flies and butterflies. A second system, superimposed on the general system and involving several of the same genes, operates within each wing subdivision to elaborate discrete pattern elements. Eyespots, which form from discrete developmental organizers, are marked by Distal-less gene expression. These circular pattern elements appear to be generated by a process similar to, and perhaps evolved from, proximodistal pattern formation in insect appendages.