E2F2 modulates cell adhesion through the transcriptional regulation of PECAM1 in multiple myeloma.

Multiple myeloma (MM) is the second most common haematological malignancy. Despite the development of new drugs and treatments in recent years, the therapeutic outcomes of patients are not satisfactory. It is necessary to further investigate the molecular mechanism underlying MM progression. Herein, we found that high E2F2 expression was correlated with poor overall survival and advanced clinical stages in MM patients. Gain- and loss-of-function studies showed that E2F2 inhibited cell adhesion and consequently activated cell epithelial-to-mesenchymal transition (EMT) and migration. Further experiments revealed that E2F2 interacted with the PECAM1 promoter to suppress its transcriptional activity. The E2F2-knockdown-mediated promotion of cell adhesion was significantly reversed by the repression of PECAM1 expression. Finally, we observed that silencing E2F2 significantly inhibited viability and tumour progression in MM cell models and xenograft mouse models respectively. This study demonstrates that E2F2 plays a vital role as a tumour accelerator by inhibiting PECAM1-dependent cell adhesion and accelerating MM cell proliferation. Therefore, E2F2 may serve as a potential independent prognostic marker and therapeutic target for MM.

The Haoqin-Huaban formula alleviates UVB-induced skin damage through HOXA11-AS-mediated stabilization of EZH2.

Exposure of skin to ultraviolet B (UVB) irradiation induces oxidative damage, immune suppression, inflammation, and skin cancer. Recently, an increase in the use of traditional Chinese medicine decoction with antioxidant properties has emerged as protection for skin tissues against UVB-induced damage. The aim of this study was to investigate mechanisms of the protective effect of the Haoqin-Huaban formula (HQHB) on UVB-induced skin damage. First, cell survival, apoptosis, and oxidative stress were evaluated upon UVB irradiation in the presence of HQHB using HaCaT cells and mice as model systems. Subsequently, bioinformatic analyses, RNA pulldown assays, RNA immunoprecipitation, luciferase reporter assays, and chromatin immunoprecipitation were conducted to verify the regulation among HQHB, hypoxia-inducible factor 1α (HIF-1α), HOXA11-AS and enhancer of zeste homolog 2 (EZH2) in HaCaT cells. In this study, we found that administration of HQHB inhibited, in a dose-dependent manner, UVB-induced skin damage by eliminating oxidative stress. HQHB was found to upregulate HOXA11-AS expression by activating HIF-1α. Furthermore, HOXA11-AS stabilized the EZH2 protein by inhibiting its ubiquitination and proteasomal degradation. Consequently, rescue assays demonstrated that HOXA11-AS promoted proliferation and inhibited apoptosis in HaCaT cells by reducing oxidative stress. Taken together, our results help to elucidate the function and regulatory mechanism of HQHB in reducing UVB-induced skin damage.

Incidence, Outcomes and Risk Factors of Heparin-Induced Thrombocytopenia After Total Joint Arthroplasty: A National Inpatient Sample Database Study.

Backgrounds: Heparin-induced thrombocytopenia (HIT) is a severe immune-mediated complication of heparin exposure, leading to negative consequences after total hip (THA) and knee arthroplasty (TKA). Materials and Methods: A retrospective study was conducted using the National Inpatient Sample (NIS) database from 2005 to 2014. The incidence and outcomes of HIT after THA or TKA were documented. Logistic regression analysis was performed to identify the postoperative HIT risk factors. Results: A total of 59 3045 patients who underwent THA and 1228 707 patients who underwent TKA were identified. The cumulative incidences were 0.02% and 0.01%, respectively. The HIT group presented significantly higher Charlson Comorbidity Index and Elixhauser Comorbidity Index scores, longer hospital stays (LOS), and higher medical costs. HIT led to a significantly higher mortality rate after THA (2.17% vs 0.16%, P = .0091). In THA, the HIT risk factors were racial minority, AIDS, pulmonary circulation disorders (PCD), psychoses, and hypertension. In TKA, the HIT risk factors were racial minority, PCD, and weight loss. Conclusion: The incidence of HIT after THA and TKA is relatively low; however, HIT significantly increases inpatient mortality, LOS, and medical cost.

Sprayable hydrogel dressing accelerates wound healing with combined reactive oxygen species-scavenging and antibacterial abilities.

Wound management poses a considerable economic burden on the global healthcare system, considering the impacts of wound infection, delayed healing and scar formation. To this end, multifunctional dressings based on hydrogels have been developed to stimulate skin healing. Herein, we describe the design, fabrication, and characterization of a sprayable hydrogel-based wound dressing loaded with cerium oxide nanoparticles (CeONs) and an antimicrobial peptide (AMP), for combined reactive oxygen species (ROS)-scavenging and antibacterial properties. We adopted a mussel-inspired strategy to chemically conjugate gelatin with dopamine motifs and prepared a hydrogel dressing with improved binding affinity to wet skin surfaces. Additionally, the release of AMP from the hydrogel demonstrated rapid release ablation and contact ablation against four representative bacterial strains, confirming the desired antimicrobial activities. Moreover, the CeONs-loaded hydrogel dressing exhibited favorable ROS-scavenging abilities. The biocompatibility of the multifunctional hydrogel dressing was further proven in vitro by culturing with HaCaT cells. Overall, the benefits of the developed hydrogel wound dressing, including sprayability, adhesiveness, antimicrobial activity, as well as ROS-scavenging and skin-remodeling ability, highlight its promissing translational potentials in wound management. STATEMENT OF SIGNIFICANCE: Various hydrogel-based wound-dressing materials have been developed to stimulate wound healing. However, from the clinical perspective, few of the current wound dressings meet all the intended multifunctional requirements of preventing infection, promoting rapid wound closure, and minimizing scar formation, while simultaneously offering the convenience of application. In the current study, we adopted a mussel-inspired strategy to functionalize the GelMA hydrogels with DOPA to fabricate GelMA-DOPA hydrogel which exhibited an enhanced binding affinity for wound surfaces, AMP HHC-36 and CeONs are further encapsulated into the GelMA-DOPA hydrogel to confer the hydrogel wound dressing with antimicrobial and ROS-scavenging abilities. The GelMA-DOPA-AMP-CeONs dressing offered the benefits of sprayability, adhesiveness, antimicrobial activity, as well as ROS-scavenging and skin-remodeling ability, which might address the therapeutic and economic burdens associated with chronic wound treatment and management.

Nano-Silicate-Reinforced and SDF-1α-Loaded Gelatin-Methacryloyl Hydrogel for Bone Tissue Engineering.

PURPOSE: Autologous bone grafts are the gold standard for treating bone defects. However, limited bone supply and morbidity at the donor site restrict its extensive use. Therefore, developing bone graft materials as an alternative to autologous grafts has gained considerable attention. Injectable hydrogels endowed with osteogenic potential have the ability to fill irregular bone defects using minimally invasive procedures and have thus been attracting researchers' attention. However, from a clinical perspective, most fabrication methods employed for the current injectable osteogenic hydrogels are difficult and inconvenient. In the current study, we fabricated an injectable osteogenic hydrogel using a simple and convenient strategy. MATERIALS AND METHODS: Gelatin-methacryloyl (GelMA) pre-polymer was synthetized. Nano silicate (SN) and stromal cell-derived factor-1 alpha (SDF-1α) were introduced into the pre-polymer to achieve injectability, controlled release property, excellent osteogenic ability, and efficient stem cell homing. RESULTS: The GelMA-SN-SDF-1α demonstrated excellent injectability via a 17-G needle at room temperature. The loaded SDF-1α exhibited a long-term controlled release pattern and efficiently stimulated MSC migration and homing. The GelMA-SN-SDF-1α hydrogel amplified cell spreading, migration, osteogenic-related biomarker expression, and matrix mineralization. The GelMA-SN-SDF-1α hydrogel filled critical-sized calvaria defects in rats and demonstrated excellent bone regeneration ability, as assessed using micro-CT scanning and histomorphometric staining. CONCLUSION: The GelMA-SN-SDF-1α hydrogel provides a simple and convenient strategy for the fabrication of injectable osteogenic graft materials.

MicroRNAs of bone marrow mesenchymal stem cell-derived exosomes regulate acute myeloid leukemia cell proliferation and apoptosis.

BACKGROUND: Acute myeloid leukemia (AML) is a malignant hematological disease, originating from hematopoiesis stem cell differentiation obstruction and clonal proliferation. New reagents or biologicals for the treatment of AML are urgently needed, and exosomes have been identified as candidate biomarkers for disease diagnosis and prognosis. This study aimed to investigate the effects of exosomes from bone marrow mesenchymal stem cells (BMSCs) on AML cells as well as the underlying microRNA (miRNA)-mediated mechanisms. METHODS: Exosomes were isolated using a precipitation method, followed by validation using marker protein expression and nanoparticle tracking analysis. Differentially expressed miRNAs were identified by deep RNA sequencing and confirmed by quantitative real-time polymerase chain reaction (qPCR). Cell proliferation was assessed by the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium inner salt method, and cell cycle progression and apoptosis were detected by flow cytometry. Functional gene expression was analyzed by qPCR and Western blotting (WB). Significant differences were determined using Student's t test or analysis of variance. RESULTS: BMSCs-derived exosomes effectively suppressed cell proliferation (both P < 0.0001 at 10 and 20 µg/mL) and cell cycle progression (P < 0.01 at G0-G1 stage), and also significantly enhanced cell apoptosis (P < 0.001) in KG-1a cells. There were 1167 differentially expressed miRNAs obtained from BMSCs-derived exosomes compared with KG-1a cell-derived exosomes (P < 0.05). Knockdown of hsa-miR-124-5p in BMSCs abrogated the effects of BMSCs-derived exosomes in regulating KG-1a such as the change in cell proliferation (both P < 0.0001 vs. normal KG-1a cell [NC] at 48 and 72 h). KG-1a cells treated with BMSCs-derived exosomes suppressed expression of structural maintenance of chromosomes 4 (P < 0.001 vs. NC by qPCR and P < 0.0001 vs. NC by WB), which is associated with the progression of various cancers. This BMSCs-derived exosomes effect was significantly reversed with knockdown of hsa-miR-124-5p (P < 0.0001 vs. NC by WB). CONCLUSIONS: BMSCs-derived exosomes suppress cell proliferation and cycle progression and promote cell apoptosis in KG-1a cells, likely acting through hsa-miR-124-5p. Our study establishes a basis for a BMSCs-derived exosomes-based AML treatment.

RAD52 aptamer regulates DNA damage repair and STAT3 in BRCA1/BRCA2­deficient human acute myeloid leukemia.

RAD52 (Radiation sensitive 52) is a key factor in DNA damage repair (DDR) bypass, which participates in single­strand annealing (SSA) after DNA damage end excision, while breast cancer type 1 susceptibility protein (BRCA1)/breast cancer type 2 susceptibility protein (BRCA2) play critical roles in homologous recombination (HR) repair. The present study aimed to determine whether RAD52­induced regulation of repair bypass occurs in acute myeloid leukemia (AML) cells and to explore the underlying mechanism. Herein, we applied an RAD52 aptamer to AML cells with downregulated BRCA1/2. RAD52 aptamer inhibited AML cell proliferation detected by cell counting, promoted cell apoptosis obtained by flow cytometry, and suppressed DNA damage repair behavior measured by comet assay and flow cytometry, after drug intervention during low expression of BRCA1/2. During this process, DDR­related cell cycle checkpoint proteins were activated, and the cells were continuously arrested in the S/G2 phase, which affected the cell damage repair process. Concurrently, the expression levels of apoptosis­related proteins were also altered. Furthermore, the expression of STAT3 and p­STAT3 was downregulated by the RAD52 aptamer, suggesting that RAD52 affects the STAT3 signaling pathway. In summary, we present a possible role for RAD52 in DDR of BRCA1/2­deficient AML cells that involves the STAT3 signaling pathway.

Incidence and risk factors associated with postoperative delirium following primary elective total hip arthroplasty: a retrospective nationwide inpatient sample database study.

BACKGROUND: Postoperative delirium is a common complication following major surgeries, leading to a variety of adverse effects. However, there is a paucity of literatures studying the incidence and risk factors associated with delirium after primary elective total hip arthroplasty (THA) using a large-scale national database. METHODS: A retrospective database analysis was performed based on Nationwide Inpatient Sample (NIS) from 2009 to 2014. Patients who underwent primary elective THA were included. Patient demographics, preoperative comorbidities, length of hospital stay (LOS), total charges, in-hospital mortality, and major and minor perioperative complications were evaluated. RESULTS: A total of 388,424 primary elective THAs were obtained from the NIS database, and the general incidence of delirium after THA was 0.90%. Patients with delirium after THA presented more preoperative comorbidities, longer LOS, extra hospital charges, and higher in-hospital mortality rate (P < 0.001). Delirium following THA was associated with major complications during hospitalization including acute renal failure and pneumonia. Preoperative risk factors associated with postoperative delirium included advanced age, alcohol or drug abuse, depression, neurological disorders, psychoses, fluid and electrolyte disorders, diabetes, weight loss, deficiency anemia, coagulopathy, hypertension, congestive heart failure, valvular disease, pulmonary circulation disorders, peripheral vascular disorders, and renal failure. Both female and obesity were detected to be protective factors. CONCLUSIONS: The results of our study identified a relatively low incidence of delirium after primary elective THA, which is as reported in the NIS and not necessarily the surgical population as a whole. Postoperative delirium of THA was associated with increased preoperative comorbidities, LOS, total charges, in-hospital mortality, and major perioperative complications including acute renal failure and pneumonia. It is of benefit to study risk factors associated with postoperative delirium to moderate its consequences.

Incidence and risk factors of in-hospital prosthesis-related complications following total hip arthroplasty: a retrospective Nationwide Inpatient Sample database study.

PURPOSE: The occurrence of prosthesis-related complications (PRCs) after total hip arthroplasty (THA) is devastating, commonly meaning implant failure and revision surgery. The purpose was to examine the incidence and risk factors of in-hospital PRCs following THA using a large-scale national database. METHODS: A retrospective database analysis was performed based on Nationwide Inpatient Sample (NIS) from 2005 to 2014. Patients who underwent THA were included. Patient demographics, hospital characteristics, length of stay (LOS), economic indicators, in-hospital mortality, comorbidities, and peri-operative complications were evaluated. RESULTS: A total of 590,122 THAs were obtained from the NIS database. The general incidence of in-hospital PRCs after THA was 1.96%, with a slight downward trend annually. Dislocation was the most common PRCs (0.23%). Patients with PRCs after THA demonstrated increased LOS, total charges, usage of Medicare, and in-hospital mortality. Risk factors of PRCs included advanced age, female, the Hispanic, the Native American, large hospital, teaching hospital, hospital in the South, Medicaid, Self-pay, alcohol abuse, anemia, coagulopathy, rheumatoid diseases, neurological disorders, depression, paralysis, psychosis, diabetes, fluid and electrolyte disorders, congestive heart failure, chronic pulmonary disease, liver disease, metastatic cancer, and weight loss. Additionally, PRCs were associated with avascular necrosis, ankylosing spondylitis, rheumatoid arthritis, femoral neck fracture, dementia, osteoporosis, acute renal failure, acute myocardial infarction, pneumonia, post-operative delirium, urinary tract infection, deep vein thrombosis, transfusion, sepsis, post-operative shock, wound dehiscence, haemorrhage/seroma/haematoma, and nerve injury. CONCLUSION: A relatively low incidence of in-hospital PRCs after THA was identified. It is of benefit to study risk factors of PRCs to ensure the appropriate management and moderate consequences.

PIM-1 kinase inhibitor SMI-4a exerts antitumor effects in chronic myeloid leukemia cells by enhancing the activity of glycogen synthase kinase 3ß.

The development of targeted tyrosine kinase inhibitors (TKIs) has succeeded in altering the course of chronic myeloid leukemia (CML). However, a number of patients have failed to respond or experienced disease relapse following TKI treatment. Proviral integration site for moloney murine leukemia virus­1 (PIM­1) is a serine/threonine kinase that participates in regulating apoptosis, cell cycle, signal transduction and transcriptional pathways, which are associated with tumor progression, and poor prognosis. SMI­4a is a selective PIM­1 kinase inhibitor that inhibits PIM­1 kinase activity in vivo and in vitro. The present study aimed to explore the mechanism underlying the antitumor effect of SMI­4a in K562 and imatinib­resistant K562 (K562/G) cell lines. It was demonstrated that SMI­4a inhibited the proliferation of K562 and K562/G cells using a WST­8 assay. The Annexin V­propidium iodide assay demonstrated that SMI­4a induced apoptosis of K562 and K562/G cells in a dose­, and time­dependent manner. Furthermore, Hoechst 33342 staining was used to verify the apoptosis rate. The clone formation assay revealed that SMI­4a significantly inhibited the colony formation capacity of K562 and K562/G cells. Western blot analysis demonstrated that SMI­4a decreased phosphorylated (p)­Ser9­glycogen synthase kinase (GSK) 3ß/pGSK3ß and inhibited the translocation of ß­catenin. In addition, the downstream gene expression of apoptosis regulator Bax and poly(ADP­ribose) polymerase­1 was upregulated, and apoptosis regulator Bcl­2 and Myc proto­oncogene protein expression levels were downregulated. Immunofluorescence results demonstrated changes in the expression level of ß­catenin in the plasma and nucleus. The results of the present study suggest that SMI­4a is an effective drug to use in combination with current chemotherapeutics for the treatment of imatinib-resistant CML.

Zoledronic acid overcomes adriamycin resistance in acute myeloid leukemia cells by promoting apoptosis.

Zoledronic acid (ZOL), a nitrogen­containing bisphosphonate, is widely used in metastatic bone disease. Previous studies indicate that ZOL has marked anti­leukemia activity, however, the underlying mechanism of action remains to be elucidated. The present study aimed to explore the mechanism of the anti­leukemia effect of ZOL in leukemia cells. It was observed that ZOL inhibited the proliferation of HL­60 and adriamycin­resistant HL­60 (HL­60/A) cells using a WST­8 assay. An Annexin V­propidium iodide indicated that ZOL induced apoptosis of the two cell types in a dose­ and time­dependent manner. Hoechst 33342 staining was also used to verify the levels of apoptosis. The colony formation assay demonstrated that ZOL significantly inhibited colony formation capacity in acute myeloid leukemia (AML) cells. This was achieved by the induction of S­phase cell cycle arrest, downregulation of B­cell lymphoma 2 (Bcl­2) and upregulation of Bcl­2 associated X protein and cleaved poly (ADP­ribose) polymerase. The results indicate that ZOL inhibited cell proliferation by inducing apoptosis via the mitochondrial apoptotic pathway and this anti­leukemic activity appeared notably enhanced in HL­60/A cells. As ZOL is already available for clinical use, these results indicate that it may be an effective addition to the chemotherapeutic strategies for AML.

Celecoxib exerts antitumor effects in HL-60 acute leukemia cells and inhibits autophagy by affecting lysosome function.

Celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, has been demonstrated to exert antitumor activity in a variety of cancer cells. The underlying mechanism involves inhibition of cell cycle progression and induction of apoptosis. Besides, celecoxib has also been found to induce autophagy in some solid tumor cells. The aim of this study was to investigate the effect of celecoxib on cell proliferation in HL-60 human acute leukemia cells and to explore the potential mechanism. HL-60 cells were exposed to various concentrations of celecoxib and cell viability was evaluated by the MTT assay. Apoptosis was analyzed with flow cytometry and the amount of autophagosome was evaluated by LysoTracker probe labelling. The expression of apoptosis- and autophagy-related proteins was assayed by Western blot and LysoSensor probe labelling was used to detect the effect of celecoxib on the lysosomal functions. The results of this study indicated that celecoxib inhibited cell proliferation in a time- and dose-dependent fashion. The flow cytometry analysis showed that celecoxib induced apoptosis at low concentrations and mainly cell necrosis at high concentrations. The Western blot test confirmed the induction of apoptosis by the upregulation of apoptosis-related proteins cleaved caspase-3 and cleaved PARP. Furthermore, this study demonstrated that celecoxib prevented the autophagic flux by inhibiting lysosome function; the fluorescence intensity of the LysoTracker probe and the level of autophagy-related proteins LC3-II and p62 were increased, but the fluorescence intensity of the LysoSensor probe was weakened. These findings show that celecoxib is an autophagy suppresser and has antitumor effects in HL-60 cells by inducing cell apoptosis and necrosis.

Atmospheric pressure covalent adduct chemical ionization tandem mass spectrometry for double bond localization in monoene- and diene-containing triacylglycerols.

We report a method to elucidate the structure of triacyl-glycerols (TAGs) containing monoene or diene fatty acyl groups by atmospheric pressure covalent adduct chemical ionization (APCACI) tandem mass spectrometry using acetonitrile as an adduct formation reagent. TAGs were synthesized with the structures ABB and BAB, where A is palmitate (C16:0) and B is an isomeric C18 monoene unsaturated at position 9, 11, or 13 or an isomeric diene unsaturated at positions 9 and 11, 10 and 12, or 9 and 12. In addition to the species at m/z 54 observed in previous CI studies of fatty acid methyl esters, we also found that ions at m/z 42, 81, and 95 undergo covalent reaction with TAGs containing double bonds to yield ions at m/z 40, 54, 81, and 95 units greater than that of the parent TAG: [M + 40]+, [M + 54]+, [M + 81]+, and [M + 95]+ ions. When collisionally dissociated, these ions fragment to produce two or three diagnostic ions that locate the double bonds in the TAG. In addition, ions [RCH=C=O + 40]+ and [RCH=C=O + 54]+ formed from collisional dissociation are of strong abundance in MS/MS spectra, and collisional activation of these ions produces two intense confirmatory diagnostic ions in the MS3 spectra. Fragment ions reflecting neutral loss of an sn-1-acyl group from [M + 40]+ and [M + 54]+ are more abundant than those reflecting neutral loss of an sn-2-acyl group, analogous to previous reports for protonated TAGs. The position of each acyl group on the glycerol backbone is thus determined by the relative abundances of these ions. Under the conditions in our instrument, the [M + 40]+ adduct is at the highest signal and also yields all information about the double bond position and TAG stereochemistry. With the exception of geometries about the double bonds, racemic TAG isomers containing two monoenes or dienes and a saturate can be fully characterized by APCACI-MS/MS/MS.

Interfacing capillary gel microfluidic chips with infrared laser desorption mass spectrometry.

We report on the fabrication and performance of a gel microfluidic chip interfaced to laser desorption/ionization (LDI) mass spectrometry with a time-of-flight mass analyzer. The chip was fabricated from poly(methylmethacrylate) with a poly(dimethyl siloxane) cover. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was performed in the channel of the microfluidic chip. After electrophoresis, the cover was removed and either the PDMS chip or the PMMA cover was mounted in a modified MALDI ion source for analysis. Ions were formed by irradiating the channel with 2.95 microm radiation from a pulsed optical parametric oscillator (OPO), which is coincident with IR absorption by N-H and O-H stretch of the gel components. No matrix was added. The microfluidic chip design allowed a decrease in the volume of material required for analysis over conventional gel slabs, thus enabling improvement in the detection limit to a pmol level, a three orders of magnitude improvement over previous studies in which desorption was achieved from an excised section of a conventional gel.

Direct from polyacrylamide gel infrared laser desorption/ionization.

The direct combination of gel electrophoresis and infrared laser desorption/ionization time-of-flight mass spectrometry has been demonstrated. We present results for infrared laser desorption and ionization mass spectrometry of peptides and proteins directly from a polyacrylamide gel without the addition of a matrix. Analyte molecules up to 6 kDa were ionized directly from a vacuum-dried sodium dodecyl sulfate-polyacrylamide gel after electrophoretic separation. Mass spectra were obtained at the wavelength of 2.94 microm, which is consistent with IR absorption by N-H and O-H stretch vibrations of water and other constituents of the gel. A 5-nmol quantity of peptide or protein was loaded per gel slot, although it was possible to obtain mass spectra from a small fraction of the gel spot. This technique shows promise for the direct identification of both parent and fragment masses of proteins contained in polyacrylamide gels.

Solid-phase reversible immobilization in microfluidic chips for the purification of dye-labeled DNA sequencing fragments.

In this manuscript, we discuss the use of photoactivated polycarbonate (PC) for purification of dye-labeled terminator sequencing fragments using solid-phase reversible immobilization (SPRI) prior to gel electrophoretic sorting of these DNAs. An immobilization bed for the DNA purification was produced by exposing a posted microchannel to UV radiation, which induced a surface photooxidation reaction, resulting in the production of carboxylate groups. The immobilization microchannel contained microposts to increase the loading level of DNAs to improve signal intensity without the need for preconcentration. By suspending the sequencing cocktail in an immobilization buffer (TEG/ethanol), the DNA fragments demonstrated a high affinity for this carboxylated surface. The loading density of DNAs to this activated surface was found to be 3.9 pmol cm(-2). The captured DNA could be subsequently released from the surface by incubation with ddH2O. SPRI cleanup of dye-terminator sequencing fragments using the photoactivated PC chip and slab gel electrophoresis produced a read length comparable to the conventional SPRI format, which utilized carboxylated magnetic beads and a magnetic field. The read length for the PC-SPRI format was found to be 620 bases with a calling accuracy of 98.9%. The PC-SPRI cleanup format was also integrated to a capillary gel electrophoresis (CGE) system. The PC-SPRI method was shown to effectively remove excess dye terminator from the CGE tract, but yielded lower plate numbers, as compared to a direct injection method with purification accomplished off-chip. The loss in efficiency was found to result primarily from the extended injection time associated with the microchip purification method.