12 research outputs found
The effect of single-stranded DNA binding protein RPA2 on XPD helicase processivity
No full textUnderstanding how proteins work together to perform vital cellular functions, such as replicating and repairing DNA, not only extends our understanding of fundamental biology, but can also lead to important medical interventions. As a necessary first step to understanding larger systems, we focus on a two-protein system involved in DNA repair. Xeroderma pigmentosum group D (XPD) is a helicase protein that plays an important role in nucleotide excision repair (NER). Its function is to unwind double-stranded DNA, allowing access to the bases that connect the strands and code genetic information. Previous work has shown that XPD activity is enhanced by the single-stranded DNA binding protein replication protein A (RPA2). However, the mechanism by which unwinding enhancement occurs is unknown. In single-molecule optical trapping experiments, we monitor – with single base-pair precision – the unwinding of a DNA hairpin by XPD in the presence of RPA. We observe the effect of RPA2 on XPD unwinding in real time and distinguish between proposed models of protein cooperation by analyzing changes in unwinding behavior with added RPA. Our data disfavor mechanisms by which RPA2 melts the duplex ahead of XPD as well as RPA2 sequestering ssDNA behind the helicase. We present our own 2-state kinetic model of XPD unwinding that we believe explains our data best. We propose that XPD has two inherent states of unwinding, high and low processivity, and that RPA2 aids unwinding by increasing the likelihood of XPD being in its more processive state.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2020-05-01The student, Barbara Stekas, accepted the attached license on 2018-04-13 at 11:22.The student, Barbara Stekas, submitted this Dissertation for approval on 2018-04-13 at 14:36.This Dissertation was approved for publication on 2018-04-13 at 17:08.DSpace SAF Submission Ingestion Package generated from Vireo submission #12233 on 2018-08-31 at 17:28:49Made available in DSpace on 2018-09-04T20:47:13Z (GMT). No. of bitstreams: 4
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Previous issue date: 2018-04-13Embargo set by: Seth Robbins for item 107396
Lift date: 2020-09-04T20:47:38Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemEmbargo set by: Seth Robbins for item 107396
Lift date: 2020-09-04T20:50:11Z
Reason: Author requested closed access (OA after 2yrs) in Vireo ETD systemLimited Restriction Lifted for Item 107396 on 2020-09-05T09:15:13Z
FPGA accelerated Facial Recognition
No full textThe ability to recognize faces is highly important in many areas of development. Though the years, the evolving technologies, enabled this process to be adapted in modern computer systems. These systems can be found in a wide variety of areas that yield significant impact. Therefore, there is an increasing demand for fast and accurate systems, able to perform facial recognition. In this thesis, a face recognition implementation on a FPGA-based System on Chip (SoC), is presented. This implementation utilizes Local Binary Patterns Histograms to extract features from test face images and Manhattan Distance to retrieve the correct match from the system’s face database. The SoC utilized is a Zynq-7030. The feature extraction and the distance computations, between the database, are implemented on the FPGA. The ARM processor of the SoC is responsible for receiving the input stream and presenting the output result, using the acquired distances. Real-time, high accuracy face recognition, with an execution time of 2.4 ms and accuracy of 78\%, is achieved through this implementation.Electrical Engineering, Mathematics and Computer ScienceComputer Engineerin
Salvage of a Below Knee Amputation Utilizing Rotationplasty Principles in a Patient with Chronic Tibial Osteomyelitis.
No full textINTRODUCTION: Chronic osteomyelitis is a disease that requires fastidious treatment to eliminate. However, when eradication is unable to be achieved through exhaustive modalities of antibiotic therapy and multiple debridements, significant resection of the infected bone and soft tissue must be considered, including amputation. Here we report of a salvage procedure for chronic osteomyelitis of the left tibia by employing a rotationplasty to avoid an above knee amputation and instead provide the patient with a below knee amputation.
CASE REPORT: A 51-year-old male presented to the emergency department after noticing dehiscence of an operative wound with exposure of an implant in the left lower extremity. Two years prior to presentation, the patient was involved in a motorcycle accident and underwent four surgeries in the Dominican Republic for an open fracture of the left tibia and fibula, including a procedure that involved the placement of an implant in the left proximal tibia. Tissue biopsies from the wound confirmed that the patient had osteomyelitis of the left proximal tibia. After extensive surgical and antibiotic intervention to eradicate the patient\u27s osteomyeltis, it was eventually determined that an amputation would be necessary. In order to avoid an above knee amputation, a salvage procedure was conducted by employing a rotationplasty to provide the patient with a below knee amputation.
CONCLUSION: When amputation is deemed necessary, sparing the knee joint is associated with decreased energy expenditures, increased patient satisfaction and overall better postoperative outcomes. As part of a multi-disciplinary team, orthopaedics, plastic surgery, infectious disease, and medical services successfully treated this case of chronic osteomyelitis of the left proximal tibia by employing a rotationplasty to avoid an above knee amputation and achieve a below knee amputation
The Correlation Between the OTA/AO Classification System and Compartment Syndrome in Both Bone Forearm Fractures
No full textOBJECTIVE: To evaluate the efficacy of using the Orthopaedic Trauma Association (OTA/AO) classification for both bone forearm fractures in predicting compartment syndrome.
DESIGN: Retrospective cohort.
SETTING: Level 1 Academic Trauma Center.
PATIENTS/PARTICIPANTS: One hundred fifty-one patients 18 years of age and older, with both bone forearm fractures diagnosed from 2001 to 2016 were categorized based on the OTA/AO classification. Patients with both bone fractures caused by gunshot wounds were excluded.
MAIN OUTCOME MEASUREMENTS: The endpoint for our study was whether forearm fasciotomies were performed based on the presence of compartment syndrome.
RESULTS: Of a total of 151 both bone forearm fractures, 15% underwent fasciotomy. Six of 80 (7.5%) grouped 22-A3, 8 of 44 (18%) grouped 22-B3, and 9 of 27 (33%) grouped 22-C underwent fasciotomies for compartment syndrome (P = 0.004). The relative risks of developing compartment syndrome for group 22-B3 versus 22-A3 was 2.42 (P = 0.08), 22-C versus 22-B3 was 1.83 (P = 0.15), and 22-C versus 22-A3 was 4.44 (P = 0.002).
CONCLUSIONS: There is a significant correlation between the OTA/AO classification and the need for fasciotomies, with group C fractures representing the highest risk. Clinicians can use this information to have a higher index of suspicion for compartment syndrome based on OTA/AO classification to help minimize the risk of a missed diagnosis.
LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence
The role of computed tomography scans in diaphyseal femur fractures following gunshot injuries: A survey of orthopaedic traumatologists.
No full textUNLABELLED: The objective of this study was to analyze if the addition of CT changed the management of femoral shaft fractures caused by gunshot wounds when compared to those managed with plain radiography alone.
METHODS: A multiple-choice, single-answer electronic survey was created to compare utility of advanced imaging when treating femur fractures resulting from gunshot injury. A total of ten femoral shaft fracture cause by gunshot injuries were selected for an online survey to be administered to orthopeaedic traumatologists. The survey compared the use the of fixation device and surgical planning before and after the CT scan.
RESULTS: A total of 99 surveys were initiated, of which 82 were completed. For proximal shaft fractures, 37% of experts reported that a CT scan should be ordered based on the radiograph alone, prior to reviewing the CT. After reviewing the CT, 5% of experts reported that they would have performed a major change, and 10% reported that they would have performed a minor change. 4% of surveyors would have changed their decision regarding ordering a CT. For distal femoral shaft fractures, 42% of experts selected that a CT scan would have been ordered prior to reviewing the CT. After reviewing the CT, 2% would have performed a major change, and 8% would have performed a minor change in management. 5% of surveyors would have changed their decision regarding ordering a CT.
CONCLUSION: Our study demonstrated that CT scans are relatively unlikely to cause major changes in fracture management of gunshot-induced fractures of femoral shaft
The role of computed tomography scans in diaphyseal femur fractures following gunshot injuries: A survey of orthopaedic traumatologists
No full textClinical photographs in the assessment of adult spinal deformity: a comparison to radiographic parameters
No full textSurgical outcomes in rigid versus flexible cervical deformities
No full textOBJECTIVE: Cervical deformity (CD) patients have severe disability and poor health status. However, little is known about how patients with rigid CD compare with those with flexible CD. The main objectives of this study were to 1) assess whether patients with rigid CD have worse baseline alignment and therefore require more aggressive surgical corrections and 2) determine whether patients with rigid CD have similar postoperative outcomes as those with flexible CD.
METHODS: This is a retrospective review of a prospective, multicenter CD database. Rigid CD was defined as cervical lordosis (CL) change \u3c 10° between flexion and extension radiographs, and flexible CD was defined as a CL change ≥ 10°. Patients with rigid CD were compared with those with flexible CD in terms of cervical alignment and health-related quality of life (HRQOL) at baseline and at multiple postoperative time points. The patients were also compared in terms of surgical and intraoperative factors such as operative time, blood loss, and number of levels fused.
RESULTS: A total of 127 patients met inclusion criteria (32 with rigid and 95 with flexible CD, 63.4% of whom were females; mean age 60.8 years; mean BMI 27.4); 47.2% of cases were revisions. Rigid CD was associated with worse preoperative alignment in terms of T1 slope minus CL, T1 slope, C2-7 sagittal vertical axis (cSVA), and C2 slope (C2S; all p \u3c 0.05). Postoperatively, patients with rigid CD had an increased mean C2S (29.1° vs 22.2°) at 3 months and increased cSVA (47.1 mm vs 37.5 mm) at 1 year (p \u3c 0.05) compared with those with flexible CD. Patients with rigid CD had more posterior levels fused (9.5 vs 6.3), fewer anterior levels fused (1 vs 2.0), greater blood loss (1036.7 mL vs 698.5 mL), more 3-column osteotomies (40.6% vs 12.6%), greater total osteotomy grade (6.5 vs 4.5), and mean osteotomy grade per level (3.3 vs 2.1) (p \u3c 0.05 for all). There were no significant differences in baseline HRQOL scores, the rate of distal junctional kyphosis, or major/minor complications between patients with rigid and flexible CD. Both rigid and flexible CD patients reported significant improvements from baseline to 1 year according to the numeric rating scale for the neck (-2.4 and -2.7, respectively), Neck Disability Index (-8.4 and -13.3, respectively), modified Japanese Orthopaedic Association score (0.1 and 0.6), and EQ-5D (0.01 and 0.05) (p \u3c 0.05). However, HRQOL changes from baseline to 1 year did not differ between rigid and flexible CD patients.
CONCLUSIONS: Patients with rigid CD have worse baseline cervical malalignment compared with those with flexible CD but do not significantly differ in terms of baseline disability. Rigid CD was associated with more invasive surgery and more aggressive corrections, resulting in increased operative time and blood loss. Despite more extensive surgeries, rigid CD patients had equivalent improvements in HRQOL compared with flexible CD patients. This study quantifies the importance of analyzing flexion-extension images, creating a prognostic tool for surgeons planning CD correction, and counseling patients who are considering CD surgery
Surgical outcomes in rigid versus flexible cervical deformities.
No full textObjectiveCervical deformity (CD) patients have severe disability and poor health status. However, little is known about how patients with rigid CD compare with those with flexible CD. The main objectives of this study were to 1) assess whether patients with rigid CD have worse baseline alignment and therefore require more aggressive surgical corrections and 2) determine whether patients with rigid CD have similar postoperative outcomes as those with flexible CD.MethodsThis is a retrospective review of a prospective, multicenter CD database. Rigid CD was defined as cervical lordosis (CL) change ResultsA total of 127 patients met inclusion criteria (32 with rigid and 95 with flexible CD, 63.4% of whom were females; mean age 60.8 years; mean BMI 27.4); 47.2% of cases were revisions. Rigid CD was associated with worse preoperative alignment in terms of T1 slope minus CL, T1 slope, C2-7 sagittal vertical axis (cSVA), and C2 slope (C2S; all p ConclusionsPatients with rigid CD have worse baseline cervical malalignment compared with those with flexible CD but do not significantly differ in terms of baseline disability. Rigid CD was associated with more invasive surgery and more aggressive corrections, resulting in increased operative time and blood loss. Despite more extensive surgeries, rigid CD patients had equivalent improvements in HRQOL compared with flexible CD patients. This study quantifies the importance of analyzing flexion-extension images, creating a prognostic tool for surgeons planning CD correction, and counseling patients who are considering CD surgery
