SEARCH · PubMed Health

Results for “Unique interface”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,729 records · Page 96Linked to original sources

PubMed2004

Analysis of roasted coffee bean volatiles by using comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry.

The volatile headspace from two coffee bean varieties, namely Arabica (Coffea arabica) and Robusta (Coffea canephora ex Froehner), were sampled by using solid-phase microextraction (SPME), and then analysed with comprehensive two-dimensional gas chromatography interfaced to a time-of-flight mass spectrometer (GC x GC-TOFMS). Two distinct column set combinations were investigated--an apolar-polar and polar-apolar configuration--and the separation achieved from each set was compared. Results were compared with a previous literature report for coffee analysed by GC x GC-FID, using an analogous polar-apolar column set combination, where authentic standards were used to confirm the position of the selected components in the 2D separation space. The present study provides independent mass spectral confirmation of component identity, and demonstrates that the relative, structured position of these components is comparable in the two experiments. Total ion current (TIC) chromatograms were processed using ChromaTOF automated data processing software. It was necessary to restrict the number of processed peaks to 1000 (S/N > 100), which required approximately 8 h for processing. Extracted ion chromatograms were generated using prominent fragment ions, and unique masses, to aid in analyte identification process, and was particularly useful in instances of component peak overlap, and for the identification of pyrazine analytes (e.g. 44, 88, 122 u). Semi-quantitative analysis was restricted to the 44 selcted components; however, the omission of peaks with S/N < 100, limiting the processed peaks to 1000, reduced the semi-quantitative application of the GC x GC-TOFMS method developed. Finally, results gained from GC x GC-TOFMS and GC x GC-qMS analyses were comparable with respect to spectral similarity assignments for the 44 target analytes.

Coffee↗

PubMed2003

Planetarium Inversum -- a space vision for Earth education.

In a planetarium, the visitor is sitting on Earth and looking into an imaginary space. The Planetarium Inversum is the opposite: visitors are sitting in a space station, looking down on Mother Earth. It is a scientifically-based information show with visitors involvement, its elements being partially virtual (Earth in space has to be projected with highest possible resolution) but also containing real structures, such as the visitors' Earth observatory with adjacent biological systems (plant cultures and other ecological life support components). Its main message concerns the limits and the vulnerability of our home planet, its uniqueness, beauty and above all, its irreplaceableness: Earth does not have an emergency exit. The Earth observatory is part of a ring shaped, rotating space station of the type designed by Wernher von Braun decades ago. Visitors are told that gravity is being substituted by centrifugal force. Both types of life support systems are being demonstrated--self regenerative life based ones and technical ones as a backup (solar electric splitting of water and chemical absorption of respiratory CO2).

Astronomy↗

PubMed2005

A structural basis for the role of nucleotide specifying residues in regulating the oligomerization of the Rv1625c adenylyl cyclase from M. tuberculosis.

The Rv1625c Class III adenylyl cyclase from Mycobacterium tuberculosis is a homodimeric enzyme with two catalytic centers at the dimer interface, and shows sequence similarity with the mammalian adenylyl and guanylyl cyclases. Mutation of the substrate-specifying residues in the catalytic domain of Rv1625c, either independently or together, to those present in guanylyl cyclases not only failed to confer guanylyl cyclase activity to the protein, but also severely abrogated the adenylyl cyclase activity of the enzyme. Biochemical analysis revealed alterations in the behavior of the mutants on ion-exchange chromatography, indicating differences in the surface-exposed charge upon mutation of substrate-specifying residues. The mutant proteins showed alterations in oligomeric status as compared to the wild-type enzyme, and differing abilities to heterodimerize with the wild-type protein. The crystal structure of a mutant has been solved to a resolution of 2.7A. On the basis of the structure, and additional biochemical studies, we provide possible reasons for the altered properties of the mutant proteins, as well as highlight unique structural features of the Rv1625c adenylyl cyclase.

Adenylyl Cyclases↗

PubMed2005

Specificity determinants on Cdc42 for binding its effector protein ACK.

Cdc42 and Rac are highly homologous members of the Rho family of small G proteins that interact with several downstream effector proteins thereby causing cytoskeletal rearrangements, cell proliferation, and differentiation. While some effectors, such as the tyrosine kinase, ACK, and the scaffold protein, WASP, are unique to Cdc42, others, such as the serine-threonine kinase, PAK, are shared with Rac. Previous mutagenesis studies identified Val42 and Leu174 as residues that selectively affect binding of Cdc42 to ACK and WASP but not to PAK. However, it is unclear whether these discriminatory residues are sufficient determinants of specificity. In this study we sought to introduce "gain-of function" mutations into Rac to allow it to bind to ACK and WASP, thereby revealing all specificity determinants. Thirteen mutations were made changing Rac residues to those in Cdc42. Equilibrium binding constants of all mutant Rac proteins to ACK, WASP, and PAK were measured. A combination of seven mutations (S41A, A42V, N43T, D47G, N52T, W56F, and R174L) was determined to be necessary to change the binding affinity of Rac for ACK from negligible (K(d) < 1 microM) to a comparable affinity to Cdc42 (K(d) 25 nM). These mutations are not confined to interface residues. We interpret these data to indicate the importance of the structure of regions of the protein distinct from the contact residues. None of these mutant Rac proteins bound WASP with a similar affinity to Cdc42. Hence, residues as yet unidentified, outside the interface, must be necessary for binding WASP.

Amino Acid Sequence↗

PubMed2000

Traumatic spinal cord injury produced by controlled contusion in mouse.

Previous work from this laboratory has described a rat spinal cord injury (SCI) model in which the mid-thoracic spinal cord is subjected to a single rapid and calibrated displacement at the site of a dorsal laminectomy. Injury is initiated at the tip of a vertical shaft driven by an electromagnetic shaker. Transducers arranged in series with the shaft record the patterns of displacement and force during the impact sequence. In the present study, this device and the relevant surgical procedures were adapted to produce a spinal contusion injury model in laboratory mice. The signal generator for the injury device has also been converted to a computer-controlled interface to permit extension of the model to other laboratories. Mice were subjected to SCI across a range of severities by varying the amplitude of displacement and the magnitude of measured preload force on the dural surface. A moderate injury produced by displacement of 0.5 mm over 25 msec resulted in initial paralysis and recovery of locomotion with chronic deficits in hindlimb function. The magnitude of the peak force, impulse, power, and energy generated at impact were correlated with behavioral outcome at 1 day postinjury, while peak displacement and impulse were the best predictors of behavioral outcome at 28 days postinjury. The shape of the force recording proved to be a highly sensitive measure of subtle variations in the spinal compartment that were otherwise difficult to detect in this small species. The results demonstrate that the electromagnetic spinal cord injury device (ESCID) can be used to produce a well-controlled contusion injury in mice. The unique features of controlled displacement and monitoring of the biomechanical parameters at the time of impact provide advantages of this model for reducing outcome variability. Use of this model in mice with naturally occurring and genetically engineered mutations will facilitate understanding of the molecular mechanisms of pathophysiology following traumatic spinal cord injury.

Animals↗

PubMed2003

Tools for the automatic identification and classification of RNA base pairs.

Three programs have been developed to aid in the classification and visualization of RNA structure. BPViewer provides a web interface for displaying three-dimensional (3D) coordinates of individual base pairs or base pair collections. A web server, RNAview, automatically identifies and classifies the types of base pairs that are formed in nucleic acid structures by various combinations of the three edges, Watson-Crick, Hoogsteen and the Sugar edge. RNAView produces two-dimensional (2D) diagrams of secondary and tertiary structure in either Postscript, VRML or RNAML formats. The application RNAMLview can be used to rearrange various parts of the RNAView 2D diagram to generate a standard representation (like the cloverleaf structure of tRNAs) or any layout desired by the user. A 2D diagram can be rapidly reformatted using RNAMLview since all the parts of RNA (like helices and single strands) are dynamically linked while moving the selected parts. With the base pair annotation and the 2D graphic display, RNA motifs are rapidly identified and classified. A survey has been carried out for 41 unique structures selected from the NDB database. The statistics for the occurrence of each edge and of each of the 12 bp families are given for the combinations of the four bases: A, G, U and C. The program also allows for visualization of the base pair interactions by using a symbolic convention previously proposed for base pairs. The web servers for BPViewer and RNAview are available at http://ndbserver.rutgers.edu/services/. The application RNAMLview can also be downloaded from this site. The 2D diagrams produced by RNAview are available for RNA structures in the Nucleic Acid Database (NDB) at http://ndbserver.rutgers.edu/atlas/.

Algorithms↗

PubMed2003

An automated noncontact deposition interface for liquid chromatography matrix-assisted laser desorption/ionization mass spectrometry.

A new multichannel deposition system was developed for off-line liquid chromatography/matrix-assisted laser desorption/ionization mass spectrometry (LC/MALDI-MS). This system employs a pulsed electric field to transfer the eluents from multiple parallel columns directly onto MALDI targets without the column outlets touching the target surface. The deposition device performs well with a wide variety of solvents that have different viscosities, vapor pressures, polarities, and ionic strengths. Surface-modified targets were used to facilitate concentration and precise positioning of samples, allowing for efficient automation of high-throughput MALDI analysis. The operational properties of this system allow the user to prepare samples using MALDI matrixes whose properties range from hydrophilic to hydrophobic. The latter, exemplified by alpha-cyano-4-hydroxycinnamic acid, were typically processed with a multistep deposition method consisting of precoating of individual spots on the target plate, sample deposition, and sample recrystallization steps. Using this method, 50 amol of angiotensin II was detected reproducibly with high signal-to-noise ratio after LC separation. Experimental results show that there is no significant decrease in chromatographic resolution using this device. To assess the behavior of the apparatus for complex mixtures, 5 microg of a tryptic digest of the cytosolic proteins of yeast was analyzed by LC/MALDI-MS and more than 13,500 unique analytes were detected in a single LC/MS analysis.

Angiotensin II↗

PubMed2006

Automated cell lineage tracing in Caenorhabditis elegans.

The invariant cell lineage and cell fate of Caenorhabditis elegans provide a unique opportunity to decode the molecular mechanisms of animal development. To exploit this opportunity, we have developed a system for automated cell lineage tracing during C. elegans embryogenesis, based on 3D, time-lapse imaging and automated image analysis. Using ubiquitously expressed histone-GFP fusion protein to label cells/nuclei and a confocal microscope, the imaging protocol captures embryogenesis at high spatial (31 planes at 1 microm apart) and temporal (every minute) resolution without apparent effects on development. A set of image analysis algorithms then automatically recognizes cells at each time point, tracks cell movements, divisions and deaths over time and assigns cell identities based on the canonical naming scheme. Starting from the four-cell stage (or earlier), our software, named starrynite, can trace the lineage up to the 350-cell stage in 25 min on a desktop computer. The few errors of automated lineaging can then be corrected in a few hours with a graphic interface that allows easy navigation of the images and the reported lineage tree. The system can be used to characterize lineage phenotypes of genes and/or extended to determine gene expression patterns in a living embryo at the single-cell level. We envision that this automation will make it practical to systematically decipher the developmental genes and pathways encoded in the genome of C. elegans.

Animals↗

PubMed2002

The crystal structure of metal-free human EF-hand protein S100A3 at 1.7-A resolution.

S100A3 is a unique member of the EF-hand superfamily of Ca(2+)-binding proteins. It binds Ca(2+) with poor affinity (K(d) = 4-35 mm) but Zn(2+) with exceptionally high affinity (K(d) = 4 nm). This high affinity for Zn(2+) is attributed to the unusual high Cys content of S100A3. The protein is highly expressed in fast proliferating hair root cells and astrocytoma pointing toward a function in cell cycle control. We determined the crystal structure of the protein at 1.7 A. The high resolution structure revealed a large distortion of the C-terminal canonical EF-hand, which most likely abolishes Ca(2+) binding. The crystal structure of S100A3 allows the prediction of one putative Zn(2+) binding site in the C terminus of each subunit of S100A3 involving Cys and His residues in the coordination of the metal ion. Zn(2+) binding induces a large conformational change in S100A3 perturbing the hydrophobic interface between two S100A3 subunits, as shown by size exclusion chromatography and CD spectroscopy.

Amino Acid Sequence↗

PubMed2006

Small interfering RNA-mediated knockdown of notch ligands in primary CD4+ T cells and dendritic cells enhances cytokine production.

The key interaction in the adaptive immune system's response to pathogenic challenge occurs at the interface between APCs and T cells. Families of costimulatory and coinhibitory molecules function in association with the cytokine microenvironment to orchestrate appropriate T cell activation programs. Recent data have demonstrated that the Notch receptor and its ligands also function at the APC:T interface. In this study, we describe synthetic small interfering RNA (siRNA) sequences targeting the human Notch ligands Delta1, Jagged1 and Jagged2. Transfection of these siRNAs into human primary CD4(+) T cells and monocyte-derived dendritic cells leads to knockdown of endogenous Notch ligand message. Knockdown of any one of these three Notch ligands in dendritic cells enhanced IFN-gamma production from allogeneic CD4(+) T cells in MLR. In contrast, Delta1 knockdown in CD4(+) T cells selectively enhanced production of IFN-gamma, IL-2, and IL-5 in response to polyclonal stimulation, while Jagged1 or Jagged2 knockdown had no effect. Strikingly, blockade of Notch cleavage with a gamma secretase inhibitor failed to affect cytokine production in this system, implying that Delta1 can influence cytokine production via a Notch cleavage-independent mechanism. These data show for the first time that the Notch pathway can be targeted by siRNA, and that its antagonism may be a unique therapeutic opportunity for immune enhancement.

Animals↗

PubMed1994

Ethnic differences in forefoot shape and the determination of shoe comfort.

The kinanthropometric aspects of comfort of fit of sport shoes has not been subjected to any great scrutiny. It is suggested that comfort of fit is largely determined by the match of foot shape to shoe shape and consequently there is a need for normative data that describe foot shape, dimension and proportion for discrete populations. A study of 708 second generation Caucasian N. American (NA) and 513 Japanese and Korean (JK) male subjects was conducted to determine normative data with respect to forefoot shape and dimension. A series of 2 height, 7 length, 1 breadth and 1 girth measures of the right foot bearing full body weight was recorded using a modified Mitutoyo digital caliper interfaced with a micro-processor. Substantial differences were noted in the incidence of digital patterning. The relative proportion of digital patterns I (1 > 2 > 3 > 4 > 5) and II (2 > 1 > 3 > 4 > 5) were NA 76.09%, 23.91%; JK 50.80% and 49.20% respectively. The distance between the pternion and the distal extremity of the second digit expressed as a percentage of the maximum foot length (MFL) was found to be 98.60% (NA) and 99.60% (JK). In addition, the distance between the pternion and the distal extremity of the fifth digit relative to MFL was 82.60% (NA) and 85.00% (JK). The implication of these data is that the anterior margin of the JK foot makes a less acute angle with the long axis of the foot than the NA population. Additional information with respect to foot breadth leads to the conclusion that the shape of the JK forefoot differs from that of the NA, with the implication that unique shoe lasts for both populations are required for optimal shoe comfort.

Adult↗

PubMed2000

Bacteria in the cold deep-sea benthic boundary layer and sediment-water interface of the NE Atlantic.

This is a short review of the current understanding of the role of microorganisms in the biogeochemistry in the deep-sea benthic boundary layer (BBL) and sediment-water interface (SWI) of the NE Atlantic, the gaps in our knowledge and some suggestions of future directions. The BBL is the layer of water, often tens of meters thick, adjacent to the sea bed and with homogenous properties of temperature and salinity, which sometimes contains resuspended detrital particles. The SWI is the bioreactive interface between the water column and the upper 1 cm of sediment and can include a large layer of detrital material composed of aggregates that have sedimented from the upper mixed layer of the ocean. This material is biologically transformed, over a wide range of time scales, eventually forming the sedimentary record. To understand the microbial ecology of deep-sea bacteria, we need to appreciate the food supply in the upper ocean, its packaging, passage and transformation during the delivery to the sea bed, the seasonality of variability of the supply and the environmental conditions under which the deep-sea bacteria grow. We also need to put into a microbial context recent geochemical findings of vast reservoirs of intrinsically labile organic material sorped onto sediments. These may well become desorped, and once again available to microorganisms, during resuspension events caused by deep ocean currents. As biotechnologists apply their tools in the deep oceans in search of unique bacteria, an increasing knowledge and understanding of the natural processes undertaken and environmental conditions experienced by deep-sea bacteria will facilitate this exploitation.

Journal Article↗

PubMed2004

Optimal search strategies for retrieving systematic reviews from Medline: analytical survey.

OBJECTIVE: To develop optimal search strategies in Medline for retrieving systematic reviews. DESIGN: Analytical survey. DATA SOURCES: 161 journals published in 2000 indexed in Medline. MAIN OUTCOME MEASURES: The sensitivity, specificity, and precision of retrieval of systematic reviews of 4862 unique terms in 782,485 combinations of one to five terms were determined by comparison with a hand search of all articles (the criterion standard) in 161 journals published during 2000 (49,028 articles). RESULTS: Only 753 (1.5%) of the 49,028 articles were systematic reviews. The most sensitive strategy included five terms and had a sensitivity of 99.9% (95% confidence interval 99.6% to 100%) and a specificity of 52% (51.6% to 52.5%). The strategy that best minimised the difference between sensitivity and specificity had a sensitivity of 98% (97% to 99%) and specificity of 90.8% (90.5% to 91.1%). Highest precision for multiterm strategies, 57% (54% to 60%), was achieved at a sensitivity of 71% (68% to 74%). The term "cochrane database of systematic reviews.jn." was the most precise single term search strategy (sensitivity of 56% (52% to 60%) and precision of 96% (94% to 98%)). These strategies are available through the "limit" screen of Ovid's search interface for Medline. CONCLUSIONS: Systematic reviews can be retrieved from Medline with close to perfect sensitivity or specificity, or with high precision, by using empirical search strategies.

Information Storage and Retrieval↗

PubMed1989

Responses of B cells from autoimmune mice to IL-5.

Three strains of mice (NZB/W F1 X NZW (NZB/W), BXSB, and MRL/Mp-lpr/lpr (MRL/lpr] develop an autoimmune disease that is clinically and immunologically similar to human SLE. A characteristic of these mice is polyclonal B cell hyperactivity. To explore whether this may be related to hyper-responsiveness to B cell stimulatory factors, we investigated the proliferative and secretory responses of B cells from these mice to semi-purified natural and rIL-5, a major regulator of B cell development in the mouse. As this lymphokine stimulates growth and differentiation of activated B cells, attention was focused on in vivo-activated B cell populations, obtained from the interface of 50/65% Percoll density gradients, from normal or autoimmune mice. This cell population from NZB/W mice secreted IgM and incorporated [3H]TdR at significantly higher levels in response to IL-5, and was more sensitive to IL-5, than a comparable population from several normal murine strains. NZB/W female and male mice displayed heightened responses to IL-5, indicating that this is characteristic of the strain in general and is not associated with the accelerated severe disease of the females. Small resting B cells from NZB/W and normal mice were insensitive to IL-5 stimulation. In contrast to NZB/W mice, no difference was observed in the magnitude of either proliferative or Ig secretory responses between in vivo-activated B cell populations from autoimmune BXSB and MRL/lpr or normal mice. Thus, B cell hyper-responsiveness to IL-5 is a characteristic of NZB/W mice but not of two other lupus-prone murine strains. As one unique feature of NZB/W mouse B cells compared to normal and other autoimmune B cells is an elevated proportion of Ly-1+ B cells, the possibility of IL-5 hyper-responsiveness being associated with this B cell subpopulation was investigated. Fluorescence-activated cell sorter sorted Ly-1+ and Ly-1- B cells both responded to IL-5, however Ly-1+ B cells consistently showed a higher stimulation index in both proliferative and Ig secretory responses to this lymphokine.

Animals↗

PubMed1998

Solution structure of a syndecan-4 cytoplasmic domain and its interaction with phosphatidylinositol 4,5-bisphosphate.

Syndecan-4, a transmembrane heparan sulfate proteoglycan, is a coreceptor with integrins in cell adhesion. It has been suggested to form a ternary signaling complex with protein kinase Calpha and phosphatidylinositol 4,5-bisphosphate (PIP2). Syndecans each have a unique, central, and variable (V) region in their cytoplasmic domains, and that of syndecan-4 is critical to its interaction with protein kinase C and PIP2. Two oligopeptides corresponding to the variable region (4V) and whole domain (4L) of syndecan-4 cytoplasmic domain were synthesized for nuclear magnetic resonance (NMR) studies. Data from NMR and circular dichroism indicate that the cytoplasmic domain undergoes a conformational transition and forms a symmetric dimer in the presence of phospholipid activator PIP2. The solution conformations of both free and PIP2-complexed 4V have been determined by two-dimensional NMR spectroscopy and dynamical simulated annealing calculations. The 4V peptide in the presence of PIP2 formed a compact dimer with two twisted strands packed parallel to each other and the exposed surface of the dimer consisted of highly charged and polar residues. The overall three-dimensional structure in solution exhibits a twisted clamp shape having a cavity in the center of dimeric interface. In addition, it has been observed that the syndecan-4V strongly interacts not only with fatty acyl groups but also the anionic head group of PIP2. These findings reveal that PIP2 promotes oligomerization of syndecan-4 cytoplasmic domain for transmembrane signaling and cell-matrix adhesion.

Amino Acid Sequence↗

PubMed1997

Multiaccommodative stimuli in VR systems: problems & solutions.

Virtual reality environments can introduce multiple and sometimes conflicting accommodative stimuli. For instance, with the high-powered lenses commonly used in head-mounted displays, small discrepancies in screen lens placement, caused by manufacturer error or user adjustment focus error, can change the focal depths of the image by a couple of diopters. This can introduce a binocular accommodative stimulus or, if the displacement between the two screens is unequal, an unequal (anisometropic) accommodative stimulus for the two eyes. Systems that allow simultaneous viewing of virtual and real images can also introduce a conflict in accommodative stimuli: When real and virtual images are at different focal planes, both cannot be in focus at the same time, though they may appear to be in similar locations in space. In this paper four unique designs are described that minimize the range of accommodative stimuli and maximize the visual system's ability to cope efficiently with the focus conflicts that remain: pinhole optics, monocular lens addition combined with aniso-accommodation, chromatic bifocal, and bifocal lens system. The advantages and disadvantages of each design are described and recommendation for design choice is given after consideration of the end use of the virtual reality system (e.g., low or high end, entertainment, technical, or medical use). The appropriate design modifications should allow greater user comfort and better performance.

Accommodation, Ocular↗

PubMed2000

Apoptosis at the interface of immunosuppressive and anticancer activities: the examples of two classes of chemical inducers, oxysterols and alkylating agents.

Recent progresses in the understanding of molecular and biochemical pathways involved in apoptotic cell death offer novel perspectives for therapeutic interventions, in particular in immunosuppressive and anti-cancer therapies. In this review, we examine some chemical, biological, and mechanistic aspects of two classes of apoptosis chemical inducers: oxysterols and alkylating agents. Oxysterols represent a vast family of oxygenated derivatives of sterols. Found in both animal and vegetal kingdoms, they can be considered as ultimate products of an oxidative stress, and are chemically inert. Some of them (7beta-hydroxycholesterol, 25-hydroxycholesterol and 7, 25-dihydroxycholesterol) are cytotoxic at micromolar concentrations towards normal and tumor cells in culture, particularly lymphocytes, and reduce the growth of murine transplanted tumors. Thus, possible applications of oxysterols in medicine as immunosuppressants or as anticancer agents may be considered. Alkylating agents, on the other hand, have been widely used in cancer chemotherapy for decades. There toxicity results from their high chemical reactivity, causing lesions to macromolecules through covalent linkage. Some representative members of this class, mainly bifunctional derivatives which possess dichloroethyl groups, such as Chlormethine, Cyclophosphamide and Chlorabucil, express a pronounced cytotoxicity against lymphoid cells, and have therefore potent immunosuppressive properties. Because they triggers apoptosis via both common and distinct mechanisms, oxysterols and alkylating agents provide unique tools for exploring the initiation of this phenomenon in lymphoid cells, and may help design novel pharmacological approaches based on apoptotic modulation of these cells.

Animals↗

PubMed1996

Privacy and security issues in a wide area health communications network.

In 1993 the first national health information service went live in New Zealand, using commercial network services for all communications. This system provides a point of connection for all health personnel, and for those with a legitimate interest in health care information (e.g. insurers): it also provides access to a number of information resources managed on behalf of the government of New Zealand (e.g. index of health care users), as well as to those developed by individual network service providers. Much of the data exchanged across this network is personalised. Since the recipient may not be known personally to the sender, it is vital that the sender has confidence that the recipient will treat personal information according to agreed criteria for privacy. A Code of Practice covering health information was developed under the New Zealand Privacy Act to ensure that the confidence to share confidential data was supported. For large organisations such as hospitals to function efficiently, they need the flexibility to be able quickly to assign user privileges to selected staff without the need for extra paperwork seeking approval from the centre. But the audit trail requires unique identification of the individual undertaking each transaction. This requirement has been addressed. Some of the data moved across the network relates to life-critical issues, e.g. clinical warnings about allergies or serious medical conditions. A failure of communications causing this vital information to be improperly represented in some way on the receivers system could have disastrous consequences. To ensure the integrity of data transfers, user installations have to be certified compliant with standard test scripts before they are authorized for access to these resources.

Accreditation↗