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PubMed1986

Evaluation of four modern home blood glucose meters including two memory meters.

Four battery-operated blood glucose reflectance meters have been tested for precision, accuracy, and convenience of use. Parallel assays on 50 venous blood samples comparing a meter and a glucose oxidase reference method gave the following regression line parameters and correlation coefficients: Diatron Easytest (Eastlords Electronics Ltd), y = 0.76x + 1.23, r = 0.93; Glucochek II (Medistron Ltd), y = 0.90x - 0.01, r = 0.98; Hypocount MX (Hypoguard Ltd), y = 0.97x - 0.14, r = 0.98; Reflolux (Boehringer Mannheim GmbH). y = 0.97x + 0.18, r = 0.99. Reflolux has to be recalibrated with a barcoded film strip for each new test strip tin and is the most precise and accurate meter. Glucochek II using both whole and half BM Test Glycemie 20-800R test strips, showed similarly good precision, and was the simplest meter to use containing only one moving operational part. Hypocount MX is the smallest of these meters, is easy to use and has a memory which can store up to 10 blood glucose readings. The memory of the Diatron Easytest is bigger and easier to use since it stores and automatically updates 25 successive glucose values; however, this was the least accurate and least precise of the meters.

Blood Glucose↗

PubMed1988

Assuring quality care: measuring and monitoring the caring process.

Everyone interested in the quality of the human services agrees that it should be largely determined by the interaction between the client and their caregivers. Unfortunately, this exchange has proven to be very difficult to measure in an accurate and timely manner. The resulting uncertainty has prevented smooth adaptation of the caring process to client needs; it has also made it virtually impossible for managers to devise workable quality control systems. This paper describes the use of miniaturized barcode technology for collection of real-time data at the point of care. With the addition of laptop computers, this technology provides for immediate feedback of information to address quality issues in care planning and management. The data bases produced by this system are sources of documentation for quality assurance as well as a dynamic foundation for quality control.

Electronic Data Processing↗

PubMed2001

A DNA microarray-based genetic screen for nonhomologous end-joining mutants in Saccharomyces cerevisiae.

We describe a microarray-based screen performed by imposing different genetic selections on thousands of yeast mutants in parallel, representing most genes in the yeast genome. The presence or absence of mutants was detected by oligonucleotide arrays that hybridize to 20-nucleotide "barcodes." We used this method to screen for components of the nonhomologous end-joining (NHEJ) pathway. Known components of the pathway were identified, as well as a gene not previously known to be involved in NHEJ, NEJ1. Nej1 protein interacts with the amino terminus of LIF1/XRCC4, a recently recognized "guardian of the genome" against cancer.

CCAAT-Binding Factor↗

PubMed2026

A rapid CRISPR-based nanodroplet assay enables direct clinical identification of mycobacteria species.

The global incidence and mortality of nontuberculous mycobacterial infections have risen sharply with population aging. In some regions, they are now surpassing Mycobacterium tuberculosis complex infections, imposing a substantial clinical and economic burden. Because nontuberous mycobacteria exhibit species-level heterogeneity and require prolonged culture for identification, their diagnosis remains slow and is frequently inaccurate. Here, we describe a multiplexed clustered regularly interspaced short palindromic repeats (CRISPR)-assisted nanodroplet differential identification (CANDI) diagnostic platform that integrates species-agnostic target amplification with species-specific CRISPR-associated protein 12a (Cas12a) detection in fluorescence-barcoded nanodroplets. By spatially compartmentalizing CRISPR reactions into color-encoded nanodroplets, CANDI overcomes the multiplexing limitations of conventional CRISPR diagnostics and enables simultaneous interrogation of multiple mycobacterial targets in a single assay. We designed a 16-plex panel that distinguishes 15 clinically relevant Mycobacterium species and subspecies. CANDI achieved high analytical sensitivity and accurate discrimination in samples containing coinfections with multiple species or subspecies. When applied to 230 clinical specimens, including sputum, tracheal aspirates, and other respiratory fluids, CANDI delivered subspecies-level results within 3.5 hours, achieving 97.08% sensitivity and 99.7% specificity relative to culture-based identification. By combining multiplexed, high-specificity CRISPR detection with scalable droplet-based engineering, CANDI has the potential to overcome the culture dependency of current diagnostics and enable species- and subspecies-level identification across the genetically complex Mycobacterium genus, offering a clinically adaptable framework for rapid, precision diagnosis of mycobacterial infections.

Humans↗

PubMed2017

A New Natural Product Analog of Blasticidin S Reveals Cellular Uptake Facilitated by the NorA Multidrug Transporter.

The permeation of antibiotics through bacterial membranes to their target site is a crucial determinant of drug activity but in many cases remains poorly understood. During screening efforts to discover new broad-spectrum antibiotic compounds from marine sponge samples, we identified a new analog of the peptidyl nucleoside antibiotic blasticidin S that exhibited up to 16-fold-improved potency against a range of laboratory and clinical bacterial strains which we named P10. Whole-genome sequencing of laboratory-evolved strains of Staphylococcus aureus resistant to blasticidin S and P10, combined with genome-wide assessment of the fitness of barcoded Escherichia coli knockout strains in the presence of the antibiotics, revealed that restriction of cellular access was a key feature in the development of resistance to this class of drug. In particular, the gene encoding the well-characterized multidrug efflux pump NorA was found to be mutated in 69% of all S. aureus isolates resistant to blasticidin S or P10. Unexpectedly, resistance was associated with inactivation of norA, suggesting that the NorA transporter facilitates cellular entry of peptidyl nucleosides in addition to its known role in the efflux of diverse compounds, including fluoroquinolone antibiotics.

Bacterial Proteins↗

PubMed2006

Identification of Histoplasma capsulatum, Blastomyces dermatitidis, and Coccidioides species by repetitive-sequence-based PCR.

The performance of repetitive-sequence-based PCR (rep-PCR) using the DiversiLab system for identification of Coccidioides species, Blastomyces dermatitidis, and Histoplasma capsulatum was assessed by comparing data obtained to colony morphology and microscopic characteristics and to nucleic acid probe results. DNA from cultures of 23 Coccidioides, 24 B. dermatitidis, 24 H. capsulatum, 3 Arthrographis, and 2 Malbranchea isolates was extracted using a microbial DNA isolation kit as recommended by Bacterial Barcodes, Inc. Rep-PCR and probe results agreed for 97.2% of the dimorphic fungi when > or =85% similarity was used as the criterion for identification. Two H. capsulatum isolates were not identified, but no isolates were misidentified. From 43 of those cultures (15 Coccidioides, 14 B. dermatitidis, 14 H. capsulatum, 3 Arthrographis, and 2 Malbranchea), DNA also was extracted using an IDI lysis kit, a simpler method. Rep-PCR and probe results agreed for 97.7% of the dimorphic fungi when a criterion of > or =90% similarity was used for identification. One H. capsulatum isolate could not be identified; no isolates were misidentified. Using > or =85% similarity for identification resulted in one misidentification. These data suggest that the DiversiLab system can be used to identify Coccidioides and B. dermatitidis and, possibly, H. capsulatum isolates.

Blastomyces↗

PubMed2026

Identification and full genome sequencing of previously unknown sandfly-borne phleboviruses using a newly established capture-based next-generation sequencing approach.

Sandfly-borne phleboviruses cause febrile illness and neuroinvasive disease in humans. While infections are reported in the Mediterranean region, the discovery of previously unknown phleboviruses in sandflies from Kenya suggests a wider geographic distribution. Detection and characterization of novel phleboviruses are often hindered by low-quality and low-viral-load samples. We developed a capture-based target enrichment next-generation sequencing approach that showed a 99%-100% fold enrichment of viral genomes from primary material and provides a robust tool for generating complete genomes of both known and previously unknown viruses. From a collection of 15,652 sandflies in Kenya, we recovered seven complete coding sequences of Embossos, Bogoria, and Kiborgoch viruses, and of two previously unknown phleboviruses, which were named Sosoik and Shable viruses. Sosoik virus shared 83% amino acid identity in its RdRp gene with that of Bogoria virus, while Shable virus shared ca. 88% amino acid identity with viruses of the Salehabad serocomplex. Additionally, a reassortant of Shable virus was detected that possessed an M segment from an undescribed Ponticelli-like virus. DNA barcoding of blood-fed sandflies revealed several potentially novel Sergentomyia species and evidence of host-feeding on humans, livestock, and reptiles, suggesting possibilities for zoonotic transmission. Overall, our findings increase the known genetic diversity of Old World sandfly-borne phlebovirus species from 18 to 25 (by 38.9%), including the detection of viruses from all pathogenic sandfly-borne phlebovirus serocomplexes in East Africa, opening new horizons in disease ecology research.IMPORTANCEKnowledge of the genetic diversity of circulating pathogens is crucial for providing appropriate diagnostics and disease management. This study established a novel capture-based target enrichment next-generation sequencing approach that enabled the near-complete viral genome recovery from primary samples, while native NGS yielded negative or poor-quality results. In addition to the five recently discovered sandfly-borne phleboviruses in Kenya, two previously unknown phleboviruses were detected in sandflies from the same region. The viruses were detected in several sandfly species, which showed diverse host-feeding behaviors, including mixed feeding on humans and chickens. The study significantly advances the understanding of sandfly-borne phleboviruses by uncovering their broader geographic distribution and genetic diversity, particularly in East Africa, highlighting the importance of expanding surveillance efforts beyond traditionally studied regions.

Phlebovirus↗

PubMed2006

Genotypic analysis of invasive Streptococcus pneumoniae from Mali, Africa, by semiautomated repetitive-element PCR and pulsed-field gel electrophoresis.

As part of a large, ongoing study of invasive infections in pediatric patients in Bamako, Mali, 106 cases of invasive pneumococcal disease were identified from June 2002 to July 2003 (J. D. Campbell et al., Pediatr. Infect. Dis. J. 23:642-649, 2004). Of the 12 serotypes present, the majority of isolates were not contained in PCV7 (the 7-valent pneumococcal conjugate vaccine), including 1 isolate that was serotype 1, 12 isolates that were serotype 2, 58 isolates that were serotype 5, 7 isolates that were serotype 7F, and 1 isolate that was serotype 12F. To determine whether clonal dissemination of the predominant serotypes had taken place, genotyping was performed on 100 S. pneumoniae isolates by using two methods: pulsed-field gel electrophoresis (PFGE) of SmaI-digested genomic DNA, and the Bacterial Barcodes repetitive-element PCR (rep-PCR) method. Criteria for delineating rep-PCR genotypes were established such that isolates of different serotypes were generally not grouped together. The two methods were equally discriminatory within a given pneumococcal serotype. PFGE separated the isolates into 15 genotypes and 7 subtypes; rep-PCR separated isolates into 15 genotypes and 6 subtypes. Using either method, isolates within serotypes 2, 5, and 7 formed three large, separate clusters containing 1 genotype each. Both methods further distinguished related subtypes within serotypes 2 and 5. Interestingly, one of the PFGE subtypes of serotype 5 is indistinguishable from the Columbia(5)-19 clone circulating in Latin America since 1994. The data support that serotypes 2 and 5 were likely to be the result of dissemination of particular clones, some of which are responsible for invasive disease over a broad population range.

Adolescent↗

PubMed2005

Comparison of an automated repetitive sequence-based PCR microbial typing system to pulsed-field gel electrophoresis for analysis of outbreaks of methicillin-resistant Staphylococcus aureus.

Rapid and sensitive methods for accurate strain delineation are essential for monitoring and preventing transmission of methicillin-resistant Staphylococcus aureus (MRSA). Pulsed-field gel electrophoresis (PFGE) has been the standard technique for strain typing most bacterial species including MRSA. The goal of this study was to compare the performance of the DiversiLab microbial typing system (Bacterial BarCodes, Inc., Houston, TX) (rep-PCR) to that of PFGE for typing MRSA isolates from five well-defined outbreaks. The DiversiLab rep-PCR assay is a rapid, semiautomated method based on PCR amplification of specific regions between noncoding repetitive sequences in the bacterial genome. rep-PCR was performed according to the manufacturer's recommendations, and the results were analyzed and dendrograms were generated using the DiversiLab analysis software (version 2.1.66 a). PFGE was performed and interpreted according to published procedures. rep-PCR results using similarity indices (SI) of 80%, 85%, and 90% were compared to PFGE analysis. In addition, intra- and interrun reproducibility was determined for rep-PCR. Overall, correct assignment to outbreak versus nonoutbreak clusters occurred for 91 of 109 isolates (85% agreement) when using a SI of 85%. For each specific outbreak, concordance between rep-PCR and PFGE ranged from 73% to 100%. There were 18 discrepant results (17%). Fourteen isolates were unique by PFGE, but they were placed in clusters by rep-PCR; the other 4 were placed in clusters different from those assigned by PFGE. Intra- and interrun reproducibility was excellent. Times to results were 12 to 24 h for rep-PCR compared to 2 to 4 days for PFGE. Rapid, standardized results and excellent reproducibility make rep-PCR a valuable tool for use in MRSA investigations. However, since rep-PCR was less discriminatory than PFGE, we recommend that it be used to screen isolates, followed by testing isolates which share the same rep-PCR pattern with a more sensitive method, such as PFGE or multilocus sequence typing.

Anti-Bacterial Agents↗

PubMed2026

Evaluation of amplicon-based nanopore sequencing for foot-and-mouth disease viruses in clinical and environmental samples.

Foot-and-mouth disease (FMD) causes severe global economic loss, necessitating rapid viral characterization. Nanopore sequencing provides a simple, real-time workflow suitable for on-site outbreak response, addressing the limitations of conventional methods. In this study, we optimized a previously published amplicon-based protocol and used this method to characterize a diverse range of samples (vesicular fluid, epithelium, serum, nasal/oral swabs, and environmental samples) collected during FMD outbreaks in 2025 in the Republic of Korea. Of the 129 samples collected, we successfully recovered complete genomes from 37 samples and VP1 sequences from 85 samples. Amplifying the S-fragment in isolation and separately barcoding each pool of PCR amplicons markedly improved sequence recovery. Furthermore, sequencing success depended on viral load and sample type. Based on comparisons with real-time RT-PCR results, whole-genome sequence (WGS) recovery exceeded 77.3% at cycle threshold (Ct) values ≤25 across all clinical samples. In the Ct > 30 category, serum samples yielded the highest WGS recovery rates (44.4%). This rate was markedly higher than the success rates observed for epithelium (20.0%) and nasal swabs (9.1%), whereas oral swabs and environmental samples failed to yield any sequences (0%). However, VP1 recovery from environmental samples reached 80% at Ct ≤ 30 (8/10), providing an approach to enable non-invasive monitoring. These findings demonstrate that amplicon-based nanopore sequencing is a practical method for the rapid generation of genomic data during FMD outbreaks.IMPORTANCEAlthough rapid detection and genomic data analysis are crucial for effective foot-and-mouth disease (FMD) control, the collection of these data can be challenging for certain sample types and impacted by reduced viral loads that result from nationwide FMD vaccination. This study provides a practical solution through large-scale evaluation of an optimized amplicon-based nanopore sequencing protocol to enhance the sequencing success rates for both clinical and environmental samples. Using a modified protocol to enhance genome recovery, we demonstrated that sequence data could be retrieved from diverse sample types (even with high real-time RT-PCR cycle threshold values). We identified serum as the most suitable sample, with environmental sample sequencing allowing for non-invasive monitoring during outbreaks. These results support the use of nanopore sequencing for rapid genomic analysis, particularly in outbreak responses, such as rapid surveillance, emergency vaccine selection, and epidemiological monitoring.

Foot-and-Mouth Disease↗

PubMed2025

Novel antibodies for identification, selection, and manipulation of T cells expressing Whitlow linker-containing CARs.

BACKGROUND: The translational study of chimeric antigen receptor (CAR) T-cell function, persistence, immunophenotype, and spatial localization after infusion is crucial for understanding factors that influence clinical outcomes. However, research has been limited by a lack of optimized tools to reliably detect CAR-engineered cells. To address this, we developed a novel platform to generate monoclonal antibodies (mAbs) targeting a linker peptide incorporated in single-chain variable fragments (scFvs) of most CAR constructs. METHODS: Using recombinant proteins and scFv linker peptides as immunogens, we generated murine mAbs against the Whitlow linker peptide, capable of binding cells expressing Whitlow linker-containing CARs in both fresh and formalin-fixed paraffin-embedded (FFPE) tissues. We evaluated these antibodies in multiple in vitro translational applications relevant to CAR T-cell research and manufacturing. RESULTS: We identified five unique mAbs reactive against the Whitlow linker and characterized their binding properties and three-dimensional structural conformation. One clone was evaluated in depth, demonstrating comparable capacity to identify CAR T cells in peripheral blood relative to other methods using anti-idiotype antibodies or recombinant CAR-target proteins. In contrast to these reagents, the anti-Whitlow mAb detects cells expressing Whitlow linker-containing CARs with different antigen specificities, including those harboring the widely employed anti-CD19 FMC63-derived scFv as well as other scFvs, such as those targeting B-cell maturation antigen (BCMA) or CD33. Importantly, the anti-Whitlow mAb identified CAR T cells in situ in archival FFPE tissues, and a DNA-barcoded format enabled their spatial characterization and immunophenotyping in highly multiplexed immunohistochemistry. We also assessed the functional consequences of antibody binding on CAR T cells in vitro and demonstrated the feasibility of anti-Whitlow mAb-mediated selective enrichment of CAR-expressing T cells for potential utility in manufacturing workflows. CONCLUSIONS: Anti-Whitlow mAb clones exhibited distinct structural and functional properties that can be leveraged for multiple applications, providing versatile tools for detection, selection and manipulation of a broad range of clinical and preclinical CAR T-cell products.

Humans↗

PubMed1993

Advanced applications of personal computers in the radiologist's office.

The author's department has found various advanced applications for the computer to be useful in daily practice. They use a data-base program to track interesting cases for later retrieval. The program automatically generates an American College of Radiology code based on the body part and diagnosis. The program is also used to track radiographic film quality. A barcode scanner attached to a computer at the film alternator is used to enter the accession number generated by the radiology information system. If any deficiencies are present, they are entered from a preprinted bar-code sheet. The bar-code scanner allows rapid entry of all examinations during the read-out session. Reports generated from the data base have been helpful in identifying and quantifying radiographic examination deficiencies. Department computers are also connected to the campus Ethernet network. This network allows radiologists to electronically verify radiology reports and to conduct electronic literature searches on the computers in their offices.

Database Management Systems↗

PubMed2025

Timing Genomic Antigen Loss in Multiple Myeloma Treated with T Cell-Redirecting Immunotherapies.

UNLABELLED: Genomic antigen loss is a recurring mechanism of resistance to chimeric antigen receptor T-cell (CAR-T) and T-cell engagers (TCE) in relapsed/refractory multiple myeloma (RRMM). Yet, it remains unclear whether these events are acquired under treatment or merely selected from preexisting, undetectable clones. By leveraging chemotherapy mutational signatures as temporal barcodes within whole-genome sequencing data, we could time genomic antigen escape in 4 of 11 patients with RRMM. In all cases, the biallelic loss was driven by genomic events acquired after exposure to BCMA- and GPCR5D-targeted CAR-T/TCE and not present at baseline. Longitudinal digital PCR analysis corroborated that resistance mutations were undetectable at therapy initiation but emerged preceding relapse. Among 752 newly diagnosed patients, only 2.7% and 9% had monoallelic inactivation of TNFRSF17 and GPCR5D, respectively, with no biallelic loss. Our findings suggest limited utility of mutational screening prior to CAR-T/TCE while underscoring the importance of dynamic surveillance during therapy. SIGNIFICANCE: Multiple myeloma has been demonstrated to recurrently develop resistance to T-cell redirection via genomic antigen escape. By leveraging chemotherapy mutational signatures, we demonstrate that somatic antigen-escape mechanisms are uniformly acquired following treatment initiation and not selected from among preexisting clones, emphasizing the importance of dynamic longitudinal surveillance for their emergence. See related commentary by Kauer et al., p. 532.

Humans↗

PubMed2005

'PACLIMS': a component LIM system for high-throughput functional genomic analysis.

BACKGROUND: Recent advances in sequencing techniques leading to cost reduction have resulted in the generation of a growing number of sequenced eukaryotic genomes. Computational tools greatly assist in defining open reading frames and assigning tentative annotations. However, gene functions cannot be asserted without biological support through, among other things, mutational analysis. In taking a genome-wide approach to functionally annotate an entire organism, in this application the approximately 11,000 predicted genes in the rice blast fungus (Magnaporthe grisea), an effective platform for tracking and storing both the biological materials created and the data produced across several participating institutions was required. RESULTS: The platform designed, named PACLIMS, was built to support our high throughput pipeline for generating 50,000 random insertion mutants of Magnaporthe grisea. To be a useful tool for materials and data tracking and storage, PACLIMS was designed to be simple to use, modifiable to accommodate refinement of research protocols, and cost-efficient. Data entry into PACLIMS was simplified through the use of barcodes and scanners, thus reducing the potential human error, time constraints, and labor. This platform was designed in concert with our experimental protocol so that it leads the researchers through each step of the process from mutant generation through phenotypic assays, thus ensuring that every mutant produced is handled in an identical manner and all necessary data is captured. CONCLUSION: Many sequenced eukaryotes have reached the point where computational analyses are no longer sufficient and require biological support for their predicted genes. Consequently, there is an increasing need for platforms that support high throughput genome-wide mutational analyses. While PACLIMS was designed specifically for this project, the source and ideas present in its implementation can be used as a model for other high throughput mutational endeavors.

Algorithms↗

PubMed2006

PathogenMIPer: a tool for the design of molecular inversion probes to detect multiple pathogens.

BACKGROUND: Here we describe PathogenMIPer, a software program for designing molecular inversion probe (MIP) oligonucleotides for use in pathogen identification and detection. The software designs unique and specific oligonucleotide probes targeting microbial or other genomes. The tool tailors all probe sequence components (including target-specific sequences, barcode sequences, universal primers and restriction sites) and combines these components into ready-to-order probes for use in a MIP assay. The system can harness the genetic variability available in an entire genome in designing specific probes for the detection of multiple co-infections in a single tube using a MIP assay. RESULTS: PathogenMIPer can accept sequence data in FASTA file format, and other parameter inputs from the user through a graphical user interface. It can design MIPs not only for pathogens, but for any genome for use in parallel genomic analyses. The software was validated experimentally by applying it to the detection of human papilloma virus (HPV) as a model system, which is associated with various human malignancies including cervical and skin cancers. Initial tests of laboratory samples using the MIPs developed by the PathogenMIPer to recognize 24 different types of HPVs gave very promising results, detecting even a small viral load of single as well as multiple infections (Akhras et al, personal communication). CONCLUSION: PathogenMIPer is a software for designing molecular inversion probes for detection of multiple target DNAs in a sample using MIP assays. It enables broader use of MIP technology in the detection through genotyping of pathogens that are complex, difficult-to-amplify, or present in multiple subtypes in a sample.

Computational Biology↗

PubMed2006

Structure of the yeast histone H3-ASF1 interaction: implications for chaperone mechanism, species-specific interactions, and epigenetics.

BACKGROUND: The histone H3/H4 chaperone Asf1 (anti-silencing function 1) is required for the establishment and maintenance of proper chromatin structure, as well as for genome stability in eukaryotes. Asf1 participates in both DNA replication-coupled (RC) and replication-independent (RI) histone deposition reactions in vitro and interacts with complexes responsible for both pathways in vivo. Asf1 is known to directly bind histone H3, however, high-resolution structural information about the geometry of this interaction was previously unknown. RESULTS: Here we report the structure of a histone/histone chaperone interaction. We have solved the 2.2 A crystal structure of the conserved N-terminal immunoglobulin fold domain of yeast Asf1 (residues 2-155) bound to the C-terminal helix of yeast histone H3 (residues 121-134). The structure defines a histone-binding patch on Asf1 consisting of both conserved and yeast-specific residues; mutation of these residues abrogates H3/H4 binding affinity. The geometry of the interaction indicates that Asf1 binds to histones H3/H4 in a manner that likely blocks sterically the H3/H3 interface of the nucleosomal four-helix bundle. CONCLUSION: These data clarify how Asf1 regulates histone stoichiometry to modulate epigenetic inheritance. The structure further suggests a physical model in which Asf1 contributes to interpretation of a "histone H3 barcode" for sorting H3 isoforms into different deposition pathways.

Animals↗

PubMed2001

Types and frequency of preanalytical mistakes in the first Thai ISO 9002:1994 certified clinical laboratory, a 6 - month monitoring.

BACKGROUND: Reliability cannot be achieved in a clinical laboratory through the control of accuracy in the analytical phase of the testing process alone. Indeed a "mistake" can be defined as any defect occuring during the testing process. In the analysis of clinical specimens, there are many possible preanalytical sources of error. Therefore, the application of quality system to laboratory testing requires total quality management throughout the laboratory process, including the preanalytical and postanalytical phases. ISO 9002:1994 is a model for quality assurance in production, installation, and servicing, which includes a number of clauses providing guidance for implementation in clinical laboratories. Our laboratory at King Chulalongkorn Memorial Hospital, the largest Thai Red Cross Society hospital, is the first clinical laboratory in Thailand with ISO 9002:1994 certified for the whole unit. METHOD: In this study, we evaluated the frequency and types of preanalytical mistakes found in our laboratory, by monitoring specimens requested for laboratory analyses from both in-patient and out-patient divisions for 6 months. RESULT: Among a total of 935,896 specimens for 941,902 analyses, 1,048 findings were confirmed as preanalytical mistakes; this was a relative frequency of 0.11 % (1,048/935,896). A total of 1,240 mistakes were identified during the study period. Comparing the preanalytical mistakes to other mistakes in the laboratory process monitored in the same setting and period, the distribution of mistakes was: preanalytical 84.52 % (1,048 mistakes), analytical 4.35 % (54 mistakes), and postanalytical 11.13 % (138 mistakes). Of 1,048 preanalytical mistakes, 998 (95.2%) originated in the care units. All preanalytical mistakes, except for 12 (1.15 %) relating to the laboratory barcode reading machine, were due to human error. CONCLUSION: Most mistakes occurred before samples were analysed, either during sampling or preparation for analysis. This suggests that co-operation with clinicians and personnel outside the laboratory is still the key to improvement of laboratory quality.

Journal Article↗

PubMed2004

Chemical genomics in yeast.

Many drugs have unknown, controversial or multiple mechanisms of action. Four recent 'chemical genomic' studies, using genome-scale collections of yeast gene deletions that were either arrayed or barcoded, have presented complementary approaches to identifying gene-drug and pathway-drug interactions.

Genomics↗