Exploring the needs of certified hand therapists regarding electronic applications.

STUDY DESIGN: Survey. INTRODUCTION: App technology may provide a beneficial clinical resource for CHTs. PURPOSE OF STUDY: This descriptive study examined beneficial components for inclusion in a potential app for certified hand therapists to use as a clinical resource based on a nationwide survey. METHODS: Certified hand therapist members of the American Society of Hand Therapists were surveyed to evaluate preferences of content to be included in a potential clinical app. RESULTS: Most of the 341 respondents were Caucasian, female, 51-60 years old, with 21+ years' experience. Respondents preferred home program illustrations, video demonstrations, evidence-based resources, postoperative protocols, and functional outcome measures. Regarding app usage, 26.7% responded "definitely use the app" and 37.5% reported "highly likely to use the app" within a price range of $1-$20. CONCLUSION: An ideal app should include home program media, evidence-based practice, postoperative protocols, and functional outcome measures related to reported diagnoses encountered in the clinic. LEVEL OF EVIDENCE: N/A.

Pharmacogenomics of adverse drug reactions: implementing personalized medicine.

Pharmacogenomics aims to investigate the genetic basis of inter-individual differences in drug responses, such as efficacy, dose requirements and adverse events. Research in pharmacogenomics has grown over the past decade, evolving from a candidate-gene approach to genome-wide association studies (GWASs). Genetic variants in genes coding for drug metabolism, drug transport and more recently human-leukocyte antigens (HLAs) have been linked to inter-individual differences in the risk of adverse drug reactions (ADRs). The tight association of specific HLA alleles with Stevens-Johnson syndrome, toxic epidermal necrolysis, drug hypersensitivity syndrome and drug-induced liver injury underscore the importance of HLA in the pathogenesis of these idiosyncratic drug hypersensitivity reactions. However, as with the search for the genetic basis for common diseases, pharmacogenomic research, including GWAS, has so far been a disappointment in discovering major gene variants responsible for the efficacy of drugs used to treat common diseases. This review focuses on the pharmacogenomics of ADRs, the underlying mechanisms and the potential use of genomic biomarkers in clinical practice for dose adjustment and the avoidance of drug toxicity. We also discuss obstacles to the implementation of pharmacogenomics and the direction of future translational research.

Direct interaction between HLA-B and carbamazepine activates T cells in patients with Stevens-Johnson syndrome.

BACKGROUND: Increasing studies have revealed that HLA alleles are the major genetic determinants of drug hypersensitivity; however, the underlying molecular mechanism remains unclear. OBJECTIVE: We adopted the HLA-B∗1502 genetic predisposition to carbamazepine (CBZ)-induced Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) as a model to study the pathologic role of HLA in delayed-type drug hypersensitivity. METHODS: We in vitro expanded CBZ-specific cytotoxic T lymphocytes (CTLs) from patients with CBZ-induced SJS/TEN and analyzed the interaction between HLA-B and CBZ analogs based on CTL response, surface plasmon resonance, peptide-binding assay, site-directed mutagenesis, and computer modeling. RESULTS: The endogenous peptide-loaded HLA-B∗1502 molecule presented CBZ to CTLs without the involvement of intracellular drug metabolism or antigen processing. The HLA-B∗1502/peptide/ß(2)-microglobulin protein complex showed binding affinity toward chemicals sharing 5-carboxamide on the tricyclic ring, as with CBZ. However, modifications of the ring structure of CBZ altered HLA-B∗1502 binding and CTL response. In addition to HLA-B∗1502, other HLA-B75 family members could also present CBZ to activate CTLs, whereas members of the HLA-B62 and HLA-B72 families could not. Three residues (Asn63, Ile95, and Leu156) in the peptide-binding groove of HLA-B∗1502 were involved in CBZ presentation and CTL activation. In particular, Asn63 shared by members of the B75 family was the key residue. Computer simulations revealed a preferred molecular conformation of the 5-carboxamide group of CBZ and the side chain of Arg62 on the B pocket of HLA-B∗1502. CONCLUSIONS: This study demonstrates a direct interaction of HLA with drugs, provides a detailed molecular mechanism of HLA-associated drug hypersensitivity, and has clinical correlations for CBZ-related drug-induced SJS/TEN.

Shared and restricted T-cell receptor use is crucial for carbamazepine-induced Stevens-Johnson syndrome.

BACKGROUND: Stevens-Johnson syndrome (SJS) and its related disease, toxic epidermal necrolysis (TEN), are life-threatening drug hypersensitivities with robust immune responses to drugs. Despite the strong HLA predisposition to drug hypersensitivities, such as HLA-B∗1502 to carbamazepine (CBZ)-induced SJS/TEN, it remains unknown whether particular T-cell receptors (TCRs) participate in recognition of small drug/peptide-HLA complexes. OBJECTIVE: Using the strong HLA predisposition in patients with CBZ-induced SJS/TEN as a model, we aimed to study the use of TCR repertoire in patients with drug hypersensitivity. METHOD: We enrolled patients with CBZ-SJS/TEN, tolerant control subjects, and healthy subjects who had no history of CBZ exposure. We isolated PBMCs from the subjects, cultured CBZ-specific T cells, and globally investigated the expression level and third complementarity-determining region length distribution of the TCR profile. We further assessed the pathogenic role of the disease-specific clonotype using real-time PCR-based tests and functional analysis. RESULTS: On drug stimulation, CBZ-specific CD8(+) T cells were expanded in vitro and activated to release granulysin. Notably, VB-11-ISGSY was identified as the most predominant clonotype and shared among different subjects. This clonotype was present in 16 (84%) of 19 patients with SJS/TEN, absent in all 17 tolerant patients, and present at a low frequency in healthy subjects (4/29 [14%]). CBZ-specific cytotoxicity could be primed in vitro in the PBMCs of healthy subjects who are carriers of HLA-B∗1502 and VB-11-ISGSY; this cytotoxicity could be blocked by an anti-TCR-VB-11 antibody. Furthermore, a single T-cell clone expressing VA-22-FISGTY/VB-11-ISGSY showed significant cytotoxicity against HLA-B∗1502-positive antigen-presenting cells and CBZ. CONCLUSION: This study establishes the key role of the TCR in the pathogenic mechanism of SJS/TEN, explains why some HLA-B∗1502 carriers are tolerant to CBZ, and provides a biomarker profile for drug hypersensitivity.

Genetic profiles of 103,106 individuals in the Taiwan Biobank provide insights into the health and history of Han Chinese.

Personalized medical care focuses on prediction of disease risk and response to medications. To build the risk models, access to both large-scale genomic resources and human genetic studies is required. The Taiwan Biobank (TWB) has generated high-coverage, whole-genome sequencing data from 1492 individuals and genome-wide SNP data from 103,106 individuals of Han Chinese ancestry using custom SNP arrays. Principal components analysis of the genotyping data showed that the full range of Han Chinese genetic variation was found in the cohort. The arrays also include thousands of known functional variants, allowing for simultaneous ascertainment of Mendelian disease-causing mutations and variants that affect drug metabolism. We found that 21.2% of the population are mutation carriers of autosomal recessive diseases, 3.1% have mutations in cancer-predisposing genes, and 87.3% carry variants that affect drug response. We highlight how TWB data provide insight into both population history and disease burden, while showing how widespread genetic testing can be used to improve clinical care.

Towards a reference genome that captures global genetic diversity.

The current human reference genome is predominantly derived from a single individual and it does not adequately reflect human genetic diversity. Here, we analyze 338 high-quality human assemblies of genetically divergent human populations to identify missing sequences in the human reference genome with breakpoint resolution. We identify 127,727 recurrent non-reference unique insertions spanning 18,048,877 bp, some of which disrupt exons and known regulatory elements. To improve genome annotations, we linearly integrate these sequences into the chromosomal assemblies and construct a Human Diversity Reference. Leveraging this reference, an average of 402,573 previously unmapped reads can be recovered for a given genome sequenced to ~40X coverage. Transcriptomic diversity among these non-reference sequences can also be directly assessed. We successfully map tens of thousands of previously discarded RNA-Seq reads to this reference and identify transcription evidence in 4781 gene loci, underlining the importance of these non-reference sequences in functional genomics. Our extensive datasets are important advances toward a comprehensive reference representation of global human genetic diversity.

Long contiguous stretches of homozygosity in the human genome.

Single nucleotide polymorphisms (SNPs) are the most common sequence variation in the human genome; they have been successfully used in mapping disease genes and more recently in studying population genetics and cancer genetics. In a population-based association study using high-density oligonucleotide arrays for whole-genome SNP genotyping, we discovered that in the genomes of unrelated Han Chinese, 34 out of 515 (6.6%) individuals contained long contiguous stretches of homozygosity (LCSHs), ranging in the size from 2.94 to 26.27 Mbp (10.22+/-5.95 Mbp). Four out of four (100%) Taiwan aborigines also demonstrated this genetic characteristic. The number of LCSH regions increased markedly in the offspring of consanguineous marriages. LCSH was also detected in Caucasian samples (11/42; 26.2%) and African American samples (2/42; 4.76%). A total of 26 LCSH regions were recurrently detected among Han Chinese, Taiwan aborigines, and Caucasians. DNA copy number determination by hybridization intensity analysis and real-time quantitative PCR (qPCR) excluded deletion as the cause of LCSH. Our results suggest that LCSHs are common in the human genome of the outbred population and this genetic characteristic could have a significant impact on population genetics and disease gene studies.

Use of the Biopharmaceutics Drug Disposition Classification System (BDDCS) to Help Predict the Occurrence of Idiosyncratic Cutaneous Adverse Drug Reactions Associated with Antiepileptic Drug Usage.

Cutaneous adverse reactions (CARs) from antiepileptic drugs (AEDs) are common, ranging from mild to life-threatening, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). The identification of subjects carrying the HLA-B*15:02, an inherited allelic variant of the HLA-B gene, and the avoidance of carbamazepine (CBZ) therapy in these subjects are strongly associated with a decrease in the incidence of carbamazepine-induced SJS/TEN. In spite of the strong genetic associations, the initiation of hypersensitivity for AEDs is still not very well characterized. Predicting the potential for other AEDs to cause adverse reactions will be undoubtedly beneficial to avoid CARs, which is the focus of this report. Here, we explore the use of the Biopharmaceutics Drug Disposition Classification System (BDDCS) to distinguish AEDs associated with and without CARs by examining the binding relationship of AEDs to HLA-B*15:02 and data from extensive reviews of medical records. We also evaluate the lack of benefit from a Hong Kong population policy on the effects of screening for HLA-B*15:02 and previous incorrect structure-activity hypotheses. Our analysis concludes that BDDCS class 2 AEDs are more prone to cause adverse cutaneous reactions than certain BDDCS class 1 AEDs and that BDDCS Class 3 drugs have the lowest levels of cutaneous adverse reactions. We propose that BDDCS Class 3 AEDs should be preferentially used for patients with Asian backgrounds (i.e., Han Chinese, Thai, and Malaysian populations) if possible and in patients predisposed to skin rashes.

A recent update of pharmacogenomics in drug-induced severe skin reactions.

In some adverse drug reactions (ADRs), genetic predisposition plays a significant role in pathogenesis, and the skin is the most frequently reported target. These severe cutaneous ADRs include bullous fixed drug eruptions (FDE), acute generalized exanthematous pustulosis (AGEP), drug-induced hypersensitivity syndrome (HSS), Stevens-Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN). The putative contribution of individual effector cells in drug hypersensitivity is briefly mentioned. To trigger these drug hypersensitivities, certain class I HLA alleles (e.g., HLA-A and HLA-B alleles) and certain class II HLA alleles (e.g., HLA-DR alleles) have been recently found to be the genetic determinants. One of the best characterized examples mentioned in this article is HLA-B*1502 to determine the incidence of carbamazepine-induced SJS. How drugs are processed and presented by these HLA alleles to activate immune responses has been explained by several hypotheses. Further implication of pharmagenomic findings to prevent drug-induced severe skin reactions can be achieved by pre-screening putative risk HLA alleles before using drugs.

Pharmacogenetics of toxic epidermal necrolysis.

IMPORTANCE OF THE FIELD: Toxic epidermal necrolysis (TEN) and Stevens-Johnson Syndrome (SJS) are two of the most severe drug-induced cutaneous reactions. Advances in genome technologies have allowed researchers to identify genetic markers associated with this drug-associated event and these have provided a potential tool for prevention. AREAS COVERED IN THIS REVIEW: Current updates of genetic biomarkers that have been identified as being associated with TEN/SJS induced by several drugs, and the associations of these markers in different populations, are discussed. WHAT THE READER WILL GAIN: The strong association of HLA-B*1502 and carbamazepine (CBZ)-induced TEN/SJS have been reported by several independent studies. This association was mostly observed in patients of Southeast Asian ancestry; it was not observed in populations with low HLA-B*1502 allele frequency. Studies also suggest that drugs with a similar chemical structure to CBZ might also induce TEN/SJS in patients with HLA-B*1502. In addition to CBZ, HLA-B*5801 was also found to associate with allopurinol-induced TEN/SJS. This strongly suggests that the associations of these markers with TEN/SJS are drug specific. TAKE HOME MESSAGE: The strong association between CBZ and HLA-B*1502 has prompted the US Food and Drug Administration to update the label for CBZ to include genetic information and to recommend genetic testing before prescribing CBZ. Patients with Asian ancestry or who are from regions prevalent in HLA-B*1502 should be screened before CBZ treatment.

Granulysin is a key mediator for disseminated keratinocyte death in Stevens-Johnson syndrome and toxic epidermal necrolysis.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are life-threatening adverse drug reactions characterized by massive epidermal necrosis, in which the specific danger signals involved remain unclear. Here we show that blister cells from skin lesions of SJS-TEN primarily consist of cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells, and both blister fluids and cells were cytotoxic. Gene expression profiling identified granulysin as the most highly expressed cytotoxic molecule, confirmed by quantitative PCR and immunohistochemistry. Granulysin concentrations in the blister fluids were two to four orders of magnitude higher than perforin, granzyme B or soluble Fas ligand concentrations, and depleting granulysin reduced the cytotoxicity. Granulysin in the blister fluids was a 15-kDa secretory form, and injection of it into mouse skin resulted in features mimicking SJS-TEN. Our findings demonstrate that secretory granulysin is a key molecule responsible for the disseminated keratinocyte death in SJS-TEN and highlight a mechanism for CTL- or NK cell--mediated cytotoxicity that does not require direct cellular contact.

Signaling pathways of LIGHT induced macrophage migration and vascular smooth muscle cell proliferation.

The biological actions of LIGHT, a member of the tumor necrosis factor superfamily, are mediated by the interaction with lymphotoxin-beta receptor (LTbetaR) and/or herpes virus entry mediator (HVEM). Previous study demonstrated high-level expressions of LIGHT and HVEM receptors in atherosclerotic plaques. To investigate the role of LIGHT in the functioning of macrophages and vascular smooth muscle cells (VSMC) in relation to atherogenesis, we determined the effects of LIGHT on macrophage migration and VSMC proliferation. We found LIGHT through HVEM activation can induce both events. LIGHT-induced macrophage migration was associated with activation of signaling kinases, including MAPKs, PI3K/Akt, NF-kappaB, Src members, and FAK. Proliferation of VSMC was also shown relating to the activation of MAPKs, PI3K/Akt, and NF-kappaB, which consequently led to alter the expression of cell cycle regulatory molecules. Down-regulation of p21, p27, and p53, and inversely up-regulation of cyclin D and RB hyper-phosphorylation were demonstrated. In conclusion, LIGHT acts as a novel mediator for macrophage migration and VSMC proliferation, suggesting its involvement in the atherogenesis.

The role of Rho-associated kinase in differential regulation by statins of interleukin-1beta- and lipopolysaccharide-mediated nuclear factor kappaB activation and inducible nitric-oxide synthase gene expression in vascular smooth muscle cells.

An optimal level of NO has protective effects in atherosclerosis, whereas large amounts contribute to septic shock. To study how statins, the potent inhibitors of cholesterol synthesis, regulate NO in the vascular wall, we determined their effects on interleukin-1beta (IL-1beta)- and lipopolysaccharide (LPS)-induced NO production in aortic vascular smooth muscle cells (VSMCs). Compared with the large amounts of NO and inducible NO synthase (iNOS) protein expression induced by LPS, the responses of IL-1beta were modest. Various statins were found to inhibit LPS-induced iNOS expression and NO production, although they potentiated IL-1beta responses. In addition, fluvastatin increased IL-1beta-induced p65 nuclear translocation and nuclear factor kappaB (NF-kappaB) activity, although it inhibited those induced by LPS. To address the role of small G proteins in statin's actions, farnesyl transferase inhibitors [alpha-hydroxyfarne-sylphosphonic acid and (2S)-2-[[(2S)-2-[(2S,3S)-2-[(2R)-2-amino-3-mercaptopropyl]amino]-3-methylpentyl]oxy]-1-oxo-3-phenylpropyl]amino]-4-(methylsulfonyl)-butanoic acid 1-methylethyl ester (L-744382)], Rac inhibitor (NSC23766), and Rho-associated kinase (ROCK) inhibitor [N-(4-pyridyl)-4-(1-aminoethyl)cyclohexanecarboxamide dihydrochloride (Y-27632)] were used. We found that Y-27632 potentiated IL-1beta-induced iNOS expression, p65 nuclear translocation, IkappaB kinase (IKK), and NF-kappaB activation, whereas it had minimal effects on LPS-induced responses. In contrast, farnesyl transferase inhibitors blocked iNOS protein expression induced by LPS and IL-1beta, whereas NSC23766 had no effect. Further studies showed that LPS down-regulated Rho and ROCK activity, whereas IL-1beta increased them, suggesting a negative role of Rho and ROCK signaling, which is regulated in contrary manners by IL-1beta and LPS, in IKK/NF-kappaB activation. Through abrogating this negative signaling, statins differentially regulate iNOS expression induced by LPS and IL-1beta in VSMCs. These differential actions of statins on iNOS gene regulation might provide an additional explanation for the pleiotropic beneficial effects of statins.

Genetic susceptibility to carbamazepine-induced cutaneous adverse drug reactions.

The anticonvulsant carbamazepine (CBZ) frequently causes cutaneous adverse drug reactions (cADRs), including maculopapular eruption (MPE), hypersensitivity syndrome (HSS), Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). We reported that SJS/TEN caused by CBZ is strongly associated with the HLA-B*1502 gene in Han Chinese. Here, we extended our genetic study to different types of CBZ-cADRs (91 patients, including 60 patients with SJS/TEN, 13 patients with hypersensitivity syndrome and 18 with maculopapular exanthema versus 144 tolerant controls). We used MALDI-TOF mass spectrometry to screen the genetic association of 278 single nucleotide polymorphisms (SNPs), which cover the major histocompatibility complex (MHC) region, tumor necrosis factor-alpha, heat shock protein and CBZ-metabolic enzymes, including CYP3A4, 2B6, 2C8, 2C9, 1A2 and epoxide hydrolase 1. In addition, we genotyped 20 microsatellites in the MHC region and performed HLA-typing to construct the recombinant map. We narrowed the susceptibility locus for CBZ-SJS/TEN to within 86 kb flanking the HLA-B gene on the extended B*1502 haplotype, and confirmed the association of B*1502 with SJS/TEN [Pc=1.6x10, odds ratio (OR)=1357; 95% confidence interval (CI)=193.4-8838.3]. By contrast to CBZ-SJS/TEN, HLA-B*1502 association was not observed in the MPE or HSS groups: MPE was associated with SNPs in the HLA-E region and a nearby allele, HLA-A*3101 (Pc=2.2x10, OR=17.5; 95% CI=4.6-66.5), and HSS with SNPs in the motilin gene (Pc=0.0064, OR=7.11; 95% CI=3.1-16.5) located terminal to the MHC class II genes. No SNPs in genes involved in CBZ metabolism were associated with CBZ-induced cADRs. Our data suggest that HLA-B*1502 could contribute to the pathogenesis of CBZ-SJS/TEN, and that genetic susceptibility to CBZ-induced cADRs is phenotype-specific.

A novel functional VKORC1 promoter polymorphism is associated with inter-individual and inter-ethnic differences in warfarin sensitivity.

Warfarin, a commonly prescribed anticoagulant, exhibited large inter-individual and inter-ethnic differences in the dose required for its anticoagulation effect. Asian populations, including Chinese, require a much lower maintenance dose than Caucasians, for which the mechanisms still remain unknown. We determined DNA sequence variants in CYP2C9 and VKORC1 in 16 Chinese patients having warfarin sensitivity (< or = 1.5 mg/day, n = 11) or resistance (> or = 6.0 mg/day, n = 5), 104 randomly selected Chinese patients receiving warfarin, 95 normal Chinese controls and 92 normal Caucasians. We identified three CYP2C9 variants, CYP2C9*3, T299A and P382L, in four warfarin-sensitive patients. A novel VKORC1 promoter polymorphism (-1639 G > A) presented in the homozygous form (genotype AA) was found in all warfarin-sensitive patients. The resistant patients were either AG or GG. Among the 104 randomly selected Chinese patients receiving warfarin, AA genotype also had lower dose than the AG/GG genotype (P < 0.0001). Frequencies of AA, AG and GG genotypes were comparable in Chinese patients receiving warfarin (79.7, 17.6 and 2.7%) and normal Chinese controls (82, 18 and 0%), but differed significantly from Caucasians (14, 47 and 39%) (P < 0.0001). The promoter polymorphism abolished the E-box consensus sequences and dual luciferase assay revealed that VOKRC1 promoter with the G allele had a 44% increase of activity when compared with the A allele. The differences in allele frequencies of A/G allele and its levels of VKORC1 promoter activity may underscore the inter-individual differences in warfarin dosage as well as inter-ethnic differences between Chinese and Caucasians.