44 results on '"Schroeder MD"'
Search Results
2. An evaluation of the outcomes associated with peritoneal catheter use in neonates undergoing cardiac surgery: A multicenter studyCentral MessagePerspective
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David M. Kwiatkowski, MD, MS, Jeffrey A. Alten, MD, Kenneth E. Mah, MD, David T. Selewski, MD, Tia T. Raymond, MD, MBA, Natasha S. Afonso, MD, MPH, Joshua J. Blinder, MD, Matthew T. Coghill, MD, David S. Cooper, MD, MPH, Joshua D. Koch, MD, Catherine D. Krawczeski, MD, David L.S. Morales, MD, Tara M. Neumayr, MD, A.K.M. Fazlur Rahman, PhD, Garrett Reichle, MS, Sarah Tabbutt, MD, PhD, Tennille N. Webb, MD, Santiago Borasino, MD, Huaiyu Zang, David Winlaw, MD, David Bailly, DO, Stuart Goldstein, MD, Katja Gist, DO, Katie L. Brandewie, MD, Priya N. Bhat, MD, John W. Diddle, MD, Muhammad Ghbeis, MD, Parthak Prodhan, MD, Xiomara Garcia, MD, Shannon Ramer, Mindy Albertson, Zahidee Rodriquez, MD, Mary Lukacs, Michael Gaies, MD, Joshua Freytag, Amanda Sammons, Hideat Abraha, John Butcher, Dominic Zanaboni, MD, Joan Sanchez de Toledo, MD, PhD, Yuliya A. Domnina, MD, Lucas Saenz, MD, Tracy Baust, Jane Kluck, RN, Jun Sasaki, MD, Aanish Raees, MD, Erika R. O'Neil, MD, Javier J. Lasa, MD, Patrick A. Phillips, Kristal M. Hock, Kevin Valentine, MD, Sachin Tadphale, MBBS, Jason R. Buckley, MD, Luke Schroeder, MD, Shanelle Clarke, MD, Wenying Zhang, MD, Andrew Smith, MD, Mohammed Absi, MD, David J. Askenazi, MD, David J. Askenazi, Parthak Prodhan, Xiomara Garcia, Shanelle Clarke, Zahidee Rodriquez, Muhammad Ghbeis, Jun Sasaki, Katie L. Brandewie, Katja Gist, Michael Gaies, Aanish Raees, Dominic Zanaboni, Joan Sanchez de Toledo, Yuliya A. Domnina, Lucas Saenz, John W. Diddle, Jane Kluck, Linda Duncan, Rebecca A. Bertrandt, Lisa J. Sosa, Priya N. Bhat, Erika R. O’Neal, Javier J. Lasa, Kevin Valentine, Jason R. Buckley, Luke Schroeder, Tammy Doman, Suzanne Viers, Wenying Zhang, Andrew H. Smith, Sachin Tadphale, Mohammed Absi, and David K. Bailly
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acute kidney injury ,fluid overload ,neonatal cardiac surgery ,peritoneal catheter ,peritoneal dialysis ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 ,Surgery ,RD1-811 - Abstract
Objective: The study objective was to determine if intraoperative peritoneal catheter placement is associated with improved outcomes in neonates undergoing high-risk cardiac surgery with cardiopulmonary bypass. Methods: This propensity score–matched retrospective study used data from 22 academic pediatric cardiac intensive care units. Consecutive neonates undergoing Society of Thoracic Surgeons–European Association for Cardio-Thoracic Surgery category 3 to 5 cardiac surgery with cardiopulmonary bypass at centers participating in the NEonatal and Pediatric Heart Renal Outcomes Network collaborative were studied to determine the association of the use of an intraoperative placed peritoneal catheter for dialysis or passive drainage with clinical outcomes, including the duration of mechanical ventilation. Results: Among 1490 eligible neonates in the NEonatal and Pediatric Heart Renal Outcomes Network dataset, a propensity-matched analysis was used to compare 395 patients with peritoneal catheter placement with 628 patients without peritoneal catheter placement. Time to extubation and most clinical outcomes were similar. Postoperative length of stay was 5 days longer in the peritoneal catheter placement cohort (17 vs 22 days, P = .001). There was a 50% higher incidence of moderate to severe acute kidney injury in the no-peritoneal catheter cohort (12% vs 18%, P = .02). Subgroup analyses between specific treatments and in highest risk patients yielded similar associations. Conclusions: This study does not demonstrate improved outcomes among neonates with placement of a peritoneal catheter during cardiac surgery. Outcomes were similar apart from longer hospital stay in the peritoneal catheter cohort. The no-peritoneal catheter cohort had a 50% higher incidence of moderate to severe acute kidney injury (12% vs 18%). This analysis does not support indiscriminate peritoneal catheter use, although it may support the utility for postoperative fluid removal among neonates at risk for acute kidney injury. A multicenter controlled trial may better elucidate peritoneal catheter effects.
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- 2024
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3. Cerebellar anaplastic ganglioglioma in a septuagenarian
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Andrew Waack, BS, Alexander Luna, BS, Jordan Norris, BS, Noah King, BS, Aastha Bhavsar, BA, Jason Schroeder, MD, and Alastair Hoyt, MD
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Cerebellum ,Ganglioglioma ,Rare ,Advanced age ,Posterior fossa ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Ganglioglioma is a rare neoplasm most common in children and adolescents. It is typically located in the supratentorial compartment, with the temporal lobe being the most common tumor location. Anaplastic ganglioglioma is a WHO grade III ganglioglioma, a rare subtype accounting for a small minority of ganglioglioma cases. Posterior fossa anaplastic ganglioglioma in an adult is incredibly rare; only 3 prior cases have been reported. Only 1 adult anaplastic ganglioglioma in the cerebellum has been reported. We present the second reported adult cerebellar anaplastic ganglioglioma.
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- 2024
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4. Which North American spine society disc herniation morphology descriptors are most associated with improvements in clinical outcomes after microdiscectomy?
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Rajkishen Narayanan, MD, Teeto Ezeonu, BA, Jeremy C. Heard, MD, Yunsoo A. Lee, MD, Caleb M. Yeung, MD, Tyler Henry, MD, Alec Kellish, MD, Meera Kohli, BS, Jose A. Canseco, MD, PhD, Mark F. Kurd, MD, Alan S. Hilibrand, MD, Alexander R. Vaccaro, MD, PhD, MBA, Gregory Schroeder, MD, Christopher Kepler, MD, MBA, and Ian David Kaye, MD
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Disc herniation ,Lumbar spine ,Microdiscectomy ,Patient-reported outcome measure ,Sequestration ,Radiculopathy ,Orthopedic surgery ,RD701-811 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
ABSTRACT: Background: The North American Spine Society (NASS) assembled the first ever comprehensive naming system for describing lumbar disc disease, including lumbar disc herniation. The objectives of this study were (1) to determine which NASS descriptors are most predictive of independent patient-reported outcomes after microdiscectomy and (2) to identify the inter-rater reliability of each NASS descriptor. Methods: Adult patients (≥18 years) who underwent a lumbar microdiscectomy from 2014-2021 were retrospectively identified. Patient-reported outcome measures (PROMs) were collected at preoperative, 3-month, and 1-year postoperative time points. Lumbar disc herniations were evaluated and classified on preoperative MRI using the NASS lumbar disc nomenclature specific to disc herniation. Results: About 213 microdiscectomy patients were included in the final analysis. Herniation descriptors exhibiting the greatest reliability included sequestration status (κ=0.83), axial disc herniation area (κ=0.83), and laterality (κ=0.83). The descriptor with the lowest inter-rater reliability was direction of migration (κ=0.53). At 3 months, a sequestered herniation was associated with lower odds of achieving the minimal clinically important difference (MCID) for ODI (p=.004) and MCS (p=.032). At 12 months, a similar trend was observed for Oswestry Disability Index (ODI) MCID achievement (p=.001). At 3 months, a herniation with larger axial area was a predictor of MCID achievement in ODI (p=.004) and the mental component summary (MCS) (p=.009). Neither association persisted at 12 months; however, larger axial disc herniation area was able to predict MCID achievement in the Visual Analogue Scale (VAS) leg (p=.031) at 12 months. Conclusions: The utility of the NASS nomenclature system in predicting postoperative outcomes after microdiscectomy has yet to be studied. We showed that sequestration status and disc area are both reliable and able to predict the odds of achieving MCID in certain clinical outcomes at 3 months and 12 months after surgery. Hence, preoperative imaging analysis of lumbar disc herniations may be useful in accurately setting patient expectations.
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- 2024
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5. Diagnosis and Treatment of Perioperative Allergic Complications: A Practical Review
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Michael J. Schroeder, MD, Casey T. Kraft, MD, Jeffrey E. Janis, MD, and Monica T. Kraft, MD
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Surgery ,RD1-811 - Abstract
Background:. Reported drug allergies are commonly encountered by surgeons and can lead to uncertainty in selecting an appropriate agent due to concerns of associated risks with related and cross-reactive drugs. This uncertainty can ultimately lead to increased infection rates. Methods:. A literature review was conducted in PubMed using a combination of the terms “allergy,” “allergic reaction,” “anaphylaxis,” and “surgery,” “surgical,” or “operating room” for articles published within the last 10 years. Publications identified with these search terms were then filtered for review articles, sorted by “best match,” and a maximum of 100 articles were manually reviewed for each combination of search terms. Results:. Search results yielded 46,484 articles, 676 of which were ultimately included for manual review, based on selection criteria. Specifically, articles selected for inclusion focused on surgical allergic reactions that were either related to mechanism of action, causative agent for the allergic reaction, timing of allergic reaction, or recommendations for appropriate management. Conclusions:. Allergic reactions can be a common occurrence in the operative room. Knowledge of likely causative agents, timing of a reaction to various agents, and appropriate management in the immediate and delayed setting can improve outcomes and safety for plastic surgery patients.
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- 2024
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6. How Much Subtalar and Ankle Joint Surface are Actually Destroyed when Reaming for Tibiotalocalcaneal (TTC) Nailing? A Cadaveric Study
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James Baker MD, Paul Schroeder MD, Tyra Kimbler BS, and Jeannie Huh MD
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Orthopedic surgery ,RD701-811 - Abstract
Category: Ankle; Trauma Introduction/Purpose: Tibiotalocalcaneal (TTC) nailing in the setting of acute ankle trauma has become increasingly popular over the last decade, with expanding indications. Potential advantages of TTC nailing include: less soft tissue dissection, decreased wound burden, and earlier weightbearing. No consensus exists as to whether formal joint preparation is necessary, and at one or both joints. While some argue that joint preparation is not necessary due to inherent joint destruction from the injury and reaming during TTC nailing, others advocate for preparation to facilitate fusion and ensure no further motion occurs at the joint which could lead to nonunion and/or hardware failure. The purpose of this study was to quantify the proportion of ankle and subtalar joint articular surface destruction associated with reaming for TTC nail fixation. Methods: Twelve cadaver feet from 6 specimens were procured. The specimens were reduced and pinned into neutral ankle dorsiflexion and neutral hindfoot alignment. Prior to reaming, each specimen was secured in a simulated supine position. Per standard TTC nailing technique, a 3.0 millimeter (mm) guide wire was inserted under fluoroscopy, retrograde from the calcaneus, through the talus, and into the tibia, followed by a 12mm opening reamer. The specimens were then dissected, exposing the tibial plafond (TP), talar dome (TD), posterior facet of the talus (PFT), and posterior facet of the calcaneus (PFC). Clinical images of each joint were obtained at an angle of 90 degrees and 12 centimeters (cm) from the joint surface. The images were processed using the ImageJ software platform. The total joint surface area, area of articular destruction, and the remaining joint surface area were calculated. The percentage of joint destruction associated with reaming was then calculated. Results: The mean surface area values and percentages of articular surface destruction are summarized in Table 1. The mean surface area (cm 2 ) after reaming was 11.82, 13.70, 9.23, and 7.79 for the TP, TD, PFT, PFC, respectively. The percentage of articular cartilage destruction was 9.32%, 10.33%, 8.89%, and 10.28% for the TP, TD, PFT, PFC, respectively. No joint destruction was observed in the middle facets of the subtalar joint. Conclusion: This study demonstrates that reaming for TTC nail placement involves only a small portion (roughly 8-10%) of each of the articular surfaces of the ankle and subtalar joints. Violation of the middle facet of the subtalar joint did not occur. These results suggest that a significant portion of hindfoot articular surface remains after reaming for TTC nail. Formal joint preparation may be beneficial to aid with fusion after TTC nail placement, particularly when used in younger, more active individuals who sustain hindfoot and ankle trauma.
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- 2023
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7. Leukoencephalopathy, calcifications, and cysts: Labrune syndrome
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Andrew Waack, BS, Jordan Norris, BS, Kathryn Becker, PhD, Alastair Hoyt, MD, and Jason Schroeder, MD
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Leukoencephalopathy ,Cerebral calcifications ,Cerebral cysts ,Microangiopathy ,Ribosomopathy ,White matter ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Labrune syndrome is an extremely rare disorder characterized by a radiological triad of leukoencephalopathy, cerebral calcifications, and cysts. The condition is the result of an autosomal mutation in the SNORD118 gene, a non-protein encoding gene that mediates rRNA synthesis. The mutation results selectively in cerebral microangiopathy through an unknown mechanism. Radiological imaging is central to diagnosing the condition, but, because the condition is so rare, there is no standard treatment paradigm. We describe the longitudinal progression of a case of Labrune syndrome, including the radiological diagnosis and imaging and surgical management.
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- 2023
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8. Impact of Antibiotic-Impregnated Spacer Design in the Treatment of Periprosthetic Hip Infection
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Eytan M. Debbi, MD, PhD, Zachary A. Rockov, MD, Ian G. Schroeder, MD, Evan D. Nigh, MD, Landon S. Polakof, MD, Sean S. Rajaee, MD, MS, Dheeraj R. Yalamanchili, MD, and Guy D. Paiement, MD
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Antibiotic-impregnated cement spacer ,Articulating spacer ,Hip periprosthetic joint infection ,Revision total hip arthroplasty ,Orthopedic surgery ,RD701-811 - Abstract
Background: Although 2-stage exchange arthroplasty, consisting of temporary insertion of an antibiotic-impregnated cement spacer (AICS), is considered the standard of care for chronic periprosthetic joint infection (PJI) in total hip arthroplasty (THA), a consensus on the AICS design has not yet been established. Ceramic-on-polyethylene AICSs (Poly-AICS) are theorized to cause less pain and better function than cement-on-bone AICS (CemB-AICS) but use non-antibiotic-impregnated components that may harbor bacteria. This study evaluates the impact of spacer design on infection-free survivorship following THA reimplantation as well as pain and function during the interim AICS stage. Methods: A retrospective review was performed of all cases of THA PJI treated with either Poly-AICS or CemB-AICS at a single high-volume academic center. Data were collected until the final follow-up after THA reimplantation with an average follow-up duration of 2.6 years. The primary outcome was infection-free survivorship after the final reimplantation. Secondary outcomes included postoperative pain scores, opioid use, time to ambulation, length of stay, complications, and discharge disposition. Results: A total of 99 cases (67 CemB-AICS; 32 Poly-AICS) were included. There were no baseline differences between the 2 groups. There were no differences in infection-free survivorship after reimplantation in survivorship curve comparisons (P = .122) and no differences in postoperative inpatient pain scores, opioid use, length of stay, time to ambulation, complications, or discharge disposition during the AICS stage. Conclusions: Patients with THA PJI treated with Poly-AICS did not have worse infection-related outcomes despite the use of non-antibiotic-impregnated components but also did not appear to have less pain or improved function during the early AICS stage.
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- 2022
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9. Publication rates of abstracts presented across 6 major spine specialty conferences
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Tariq Z. Issa, BA, Yunsoo Lee, MD, Mark J. Lambrechts, MD, Christopher Reynolds, BS, Ryan Cha, BS, James Kim, BS, Jose A. Canseco, MD, PhD, Alexander R. Vaccaro, MD, MBA, PhD, Christopher K. Kepler, MD, Gregory D. Schroeder, MD, and Alan S. Hilibrand, MD
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Spine ,Conference ,Annual meeting ,Publication rate ,Abstract ,Poster presentation ,Orthopedic surgery ,RD701-811 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Background: Although scientific researchers aim to present their projects at academic conferences as a step toward publication, not all projects mature to become a peer-reviewed manuscript. The publication rate of meetings can be utilized to assess the quality of presented research. Our objective was to evaluate the contemporary publication rate of abstracts presented at spine conferences. Methods: We reviewed annual meeting programs of North American Spine Society (NASS), Scoliosis Research Society (SRS), International Meeting on Advanced Spine Techniques (IMAST), Spine Global Spine Congress (GSC), Lumbar Spine Research Society (LSRS), and Cervical Spine Research Society (CSRS) from 2017 to 2019. Abstracts were identified as published from PubMed and Google search. From published manuscripts, journal name and open access status was collected. Journal impact factors were collected from the 2021 Journal Citation Reports. Results: A total of 3,091/5,722 (54%) abstracts were published, ranging from 44.5% to 66.3%. Publication rate of posters and podiums ranged from 39.8% to 64.8% and 51.6% to 67.2%, respectively. Podium presentations were more likely to be published than posters (59.6% vs. 47.2%, p
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- 2023
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10. Nuclear imaging in the identification of aberrant vascular anatomy prior to hepatic arterial infusion
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Tristan R. Lawson, MD and Jennifer A. Schroeder, MD
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Nuclear medicine ,Colon cancer ,Hepatic arterial infusion ,Vascular ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Hepatic arterial infusion (HAI) pumps are a specialized therapeutic modality designed to deliver high dose local chemotherapy to hepatic metastases in carefully selected patients resulting in improved survival, with patients living an average of 2 years longer than those who did not receive HAI pumps. While beneficial, these chemoinfusion pumps require a multidisciplinary approach to ensure safe and effective treatment for the patient. Here, we present a case where scintigraphic evaluation by the nuclear medicine department directly affected management of a patient with a hepatic arterial infusion pump. Variant vascular anatomy was initially discovered on the postoperative Tc-99m MAA SPECT/CT and was ultimately embolized by interventional radiology prior to initiation of chemoinfusion. This case report demonstrates the utility of obtaining nuclear medicine scintigraphy prior to chemoinfusion in patients with hepatic arterial infusion pumps.
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- 2022
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11. Avelumab in Combination With Cetuximab and Chemotherapy as First-Line Treatment for Patients With Advanced Squamous NSCLC
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Zoran Andric, MD, Gabriella Gálffy, MD, Manuel Cobo Dols, MD, Barna Szima, MD, Goran Stojanovic, MD, Marina Petrovic, MD, Enriqueta Felip, MD, David Vicente Baz, MD, Santiago Ponce Aix, MD, Oscar Juan-Vidal, MD, Zsuzsanna Szalai, MD, Gyorgy Losonczy, MD, Antonio Calles Blanco, MD, Reyes Bernabe, MD, Gema García Ledo, MD, Andrés Aguilar Hernández, MD, Klaus Duecker, PhD, Dongli Zhou, PhD, Andreas Schroeder, MD, Guelseren Guezel, MD, and Fortunato Ciardiello, MD, PhD
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Avelumab ,Cetuximab ,PD-L1 ,EGFR ,Non–small cell lung cancer ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Introduction: We present the results of a phase 2a trial of first-line avelumab (anti–programmed death-ligand 1 antibody) plus cetuximab (anti–EGFR antibody) in patients with advanced squamous NSCLC. Methods: Patients with recurrent or metastatic squamous NSCLC received avelumab 800 mg (d 1 and 8), cetuximab 250 mg/m2 (d 1) and 500 mg/m2 (d 8), cisplatin 75 mg/m2 (d 1), and gemcitabine 1250 mg/m2 (d 1 and 8) for four 3-week cycles, followed by avelumab 800 mg and cetuximab 500 mg/m2 every 2 weeks. The primary end point was the best overall response; the secondary end points were progression-free survival, duration of response, overall survival, and safety. Efficacy analyses were reported from an updated data cutoff. Results: A total of 43 patients were enrolled. The median follow-up was 6.6 months for the primary analyses and 9.2 months for the efficacy analyses. In the efficacy analyses, 15 patients had a confirmed partial response (objective response rate, 34.9% [95% confidence interval: 21.0%–50.9%]), and the median duration of response was 7.1 months (95% confidence interval: 4.2–12.5 mo). The median progression-free survival and overall survival were 6.1 months and 10.0 months, respectively. In the safety analyses (primary analysis), 38 patients (88.4%) had a treatment-related adverse event, of whom 24 (55.8%) had a grade 3 or higher treatment-related adverse event. Conclusions: The combination of avelumab + cetuximab and chemotherapy showed antitumor activity and tolerable safety; however, the ORR was not improved compared with those reported for current standards of care (NCT03717155).
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- 2023
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12. A rare case of cavitary lung lesions in an adolescent: Granulomatosis with polyangiitis
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Sekhar Iyer, MD, Michael A Simon, MD, Donald Schroeder, MD, and Lyle Gesner, MD
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Pediatrics ,Adolescent ,Cavitary lung lesion ,Wegners ,Granulomatosis with Polyangiitis ,ANCA ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Granulomatosis with Polyangiitis (GPA) is a life threatening disease if left untreated which predominantly affects the adult population. As clinical presentation is often non-specific there is a heavy reliance on radiologic, laboratory and biopsy findings in diagnosis. We present a case of a 17-year-old male who presented with a history of tea colored urine and recurrent epistaxis who now complained of cough and congestion. The patient failed multiple courses of outpatient antibiotics and a CT of the chest while in the ED demonstrated multiple cavitary lesions. Subsequent workup and biopsy confirmed the diagnosis of GPA. It is important for the Radiologist and other clinicians to keep GPA in their differential when presented with a cavitary lung lesion as prompt treatment is required for good outcomes.
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- 2021
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13. Availability of essential diagnostics in ten low-income and middle-income countries: results from national health facility surveys
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Harika Yadav, MD, Devanshi Shah, BA, Shahin Sayed, MD, Susan Horton, ProfPhD, and Lee F Schroeder, MD
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Public aspects of medicine ,RA1-1270 - Abstract
Summary: Background: Pathology and laboratory medicine diagnostics and diagnostic imaging are crucial to achieving universal health coverage. We analysed Service Provision Assessments (SPAs) from ten low-income and middle-income countries to benchmark diagnostic availability. Methods: Diagnostic availabilities were determined for Bangladesh, Haiti, Malawi, Namibia, Nepal, Kenya, Rwanda, Senegal, Tanzania, and Uganda, with multiple timepoints for Haiti, Kenya, Senegal, and Tanzania. A smaller set of diagnostics were included in the analysis for primary care facilities compared with those expected at hospitals, with 16 evaluated in total. Surveys spanned 2004–18, including 8512 surveyed facilities. Country-specific facility types were mapped to basic primary care, advanced primary care, or hospital tiers. We calculated percentages of facilities offering each diagnostic, accounting for facility weights, stratifying by tier, and for some analyses, region. The tier-level estimate of diagnostic availability was defined as the median of all diagnostic-specific availabilities at each tier, and country-level estimates were the median of all diagnostic-specific availabilities of each of the tiers. Associations of country-level diagnostic availability with country income as well as (within-country) region-level availability with region-specific population densities were determined by multivariable linear regression, controlling for appropriate covariates including tier. Findings: Median availability of diagnostics was 19·1% in basic primary care facilities, 49·2% in advanced primary care facilities, and 68·4% in hospitals. Availability varied considerably between diagnostics, ranging from 1·2% (ultrasound) to 76·7% (malaria) in primary care (basic and advanced) and from 6·1% (CT scan) to 91·6% (malaria) in hospitals. Availability also varied between countries, from 14·9% (Bangladesh) to 89·6% (Namibia). Availability correlated positively with log(income) at both primary care tiers but not the hospital tier, and positively with region-specific population density at the basic primary care tier only. Interpretation: Major gaps in diagnostic availability exist in many low-income and middle-income countries, particularly in primary care facilities. These results can serve as a benchmark to gauge progress towards implementing guidelines such as the WHO Essential Diagnostics List and Priority Medical Devices initiatives. Funding: Bill & Melinda Gates Foundation.
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- 2021
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14. Open Versus Endoscopic Carpal Tunnel Release: A Comparison of Opioid Prescription Patterns and Occupational Therapy Referrals
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Michael J. Schroeder, MD, Nihaal Reddy, BS, Andrew Rust, BS, Andrew L. O’Brien, MD, MPH, and Sonu A. Jain, MD
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Surgery ,RD1-811 - Published
- 2021
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15. Robotic assisted fixation of sacral fractures
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Yoram A. Weil, MD, Amal Khoury, MD, Rami Mosheiff, MD, Leon Kaplan, MD, Meir Liebergall, MD, and Josh E. Schroeder, MD
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Orthopedic surgery ,RD701-811 - Abstract
Abstract. Objectives:. Sacral fractures that require fixation are a challenge for the orthopaedic surgeon. Due to anatomical consideration, implant insertion is not risk free, and requires a steep learning curve. A robotic system has been successfully used in pedicle screws insertion and can be also used for iliosacral screws. The aim of the study was to demonstrate the use of the robot in the treatment of unstable sacral fractures. Design:. Retrospective case series. Setting:. An academic level I trauma center. Patients:. Fourteen patients with sacral fractures were eligible for robotic assisted treatment. These included 9 high-energy fractures, 4 osteoporotic fractures, and 1 pathological fracture. Intervention:. Fixation constructs included iliosacral screws, transiliac screws, lumbopelvic fixation, sacroplasty, or a combination of the above techniques. A Renaissance robot was mounted on a multidirectional bridge that was attached to the patients spine and implant trajectories were planned either on preoperative or intraoperative 3D scans. Guide wires were inserted percutaneously and screws were placed subsequently. Main outcome measurements:. Accuracy of implant placement, operating room and fluoroscopy time. Results:. Mean patient age was 36 (17–84), and number of screws, including iliosacral and pedicular ranged 1–14 per patient (average 4.25). Mean operative time was 150 minutes (range 90–300). Average fluoroscopic time was 18 seconds (7–42) for 2D and 40 seconds (12–72) for 3D imaging. All fractures healed, no hardware failure was observed. All hardware was always within bony confines, and no procedure-related neurological deficits were observed. Conclusion:. Robotic assisted fixation of sacral fracture is a safe and reproduceable method, allowing precise and accurate implant placement.
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- 2019
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16. Emergency Medicine Resident Rotations Abroad: Current Status and Next Steps
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Stephen C. Morris, MD, MPH and Erika D. Schroeder, MD, MPH
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International rotations ,resident safety ,Medicine ,Medical emergencies. Critical care. Intensive care. First aid ,RC86-88.9 - Abstract
Introduction: International rotations for residents are increasingly popular, but there is a dearth of evidence to demonstrate that these rotations are safe and that residents have appropriate training and support to conduct them. Methods: A survey was sent to all U.S. emergency medicine (EM) residencies with publicly available e-mail addresses. The survey documents and examines the training and support that emergency medicine residents are offered for international rotations and the frequency of adverse safety events. Results: 72.5% of program director responded that their residents are participating in rotations abroad. However, only 15.4% of programs reported offering training specific to working abroad. The results point to an increased need for specific training and insurance coverage. Conclusion: Oversight of international rotations should be improved to guarantee safety and education benefit.
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- 2016
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17. Abstract: Universal Measures of Support Are Needed: A Cross-Sectional Study of Health Literacy in Dupuytren’s Patients
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Melissa Roy, MDCM, Karen Okrainec, MD, MSc, FRCPC, Christine B. Novak, MSc, PhD, Herbert P. von Schroeder, MD, MSc, FRCSC, David R. Urbach, MD, MSc, FRCSC, FACS, and Steven J. McCabe, MD, MSc, FRCSC
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Surgery ,RD1-811 - Published
- 2018
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18. Practically Saline
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Jonathan Schroeder MD, Catherine O’Neal MD, and Tonya Jagneaux MD
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Medicine (General) ,R5-920 ,Pathology ,RB1-214 - Abstract
Introduction . In December 2014, the Food and Drug Administration issued a recall of all Wallcur simulation products due to reports of their use in clinical practice. We present a case of septic shock and multiorgan failure after the accidental intravenous infusion of a nonsterile Wallcur simulation product. Case . The patient presented with symptoms of rigors and dyspnea occurring immediately after infusion of Wallcur Practi-0.9% saline. Initial laboratory evidence was consistent with severe septic shock and multiorgan dysfunction. His initial lactic acid level was 9 mmol/L (reference range = 0.5-2.2), and he had evidence of acute kidney injury and markers of disseminated intravascular coagulation. All 4 blood culture bottles isolated multidrug-resistant Empedobacter brevis . The patient recovered from his illness and was discharged with ciprofloxacin therapy per susceptibilities. Discussion . This patient represents the first described case of severe septic shock associated with the infusion of a Wallcur simulation product. Intravenous inoculation of a nonsterile fluid is rare and exposes the patient to unusual environmental organisms, toxins, or unsafe fluid characteristics such as tonicity. During course of treatment, we identified the possible culprit to be a multidrug-resistant isolate of Empedobacter brevis . We also discuss the systemic failures that led to this outbreak.
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- 2015
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19. Abstract: One Third of Plastic and Surgical Patients Have Limited Health Literacy: A Systematic Review and Meta-Analysis
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Mélissa Roy, MDCM, Joseph P. Corkum, MD, Steven J. McCabe, MD, MSc, FRCSC, Christine B. Novak, BSc(Kin), BSc(PT), MSc, PhD, Herb von Schroeder, MD, MSc, FRCSC, David R. Urbach, MD, MSc, FRCSC, FACS, and Karen Okrainec, MD, MSc, FRCPC
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Surgery ,RD1-811 - Published
- 2017
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20. A new member of the flavodoxin superfamily from Fusobacterium nucleatum that functions in heme trafficking and reduction of anaerobilin.
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McGregor AK, Chan ACK, Schroeder MD, Do LTM, Saini G, Murphy MEP, and Wolthers KR
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- Humans, Flavin Mononucleotide metabolism, Iron metabolism, Oxidation-Reduction, Biological Transport, Genes, Bacterial, Bacterial Proteins chemistry, Bacterial Proteins classification, Bacterial Proteins genetics, Bacterial Proteins metabolism, Protein Domains, Fusobacterium Infections microbiology, Flavodoxin chemistry, Flavodoxin classification, Flavodoxin genetics, Flavodoxin metabolism, Fusobacterium nucleatum chemistry, Fusobacterium nucleatum genetics, Fusobacterium nucleatum metabolism, Heme metabolism, Tetrapyrroles metabolism
- Abstract
Fusobacterium nucleatum is an opportunistic oral pathogen that is associated with various cancers. To fulfill its essential need for iron, this anaerobe will express heme uptake machinery encoded at a single genetic locus. The heme uptake operon includes HmuW, a class C radical SAM-dependent methyltransferase that degrades heme anaerobically to release Fe
2+ and a linear tetrapyrrole called anaerobilin. The last gene in the operon, hmuF encodes a member of the flavodoxin superfamily of proteins. We discovered that HmuF and a paralog, FldH, bind tightly to both FMN and heme. The structure of Fe3+ -heme-bound FldH (1.6 Å resolution) reveals a helical cap domain appended to the ⍺/β core of the flavodoxin fold. The cap creates a hydrophobic binding cleft that positions the heme planar to the si-face of the FMN isoalloxazine ring. The ferric heme iron is hexacoordinated to His134 and a solvent molecule. In contrast to flavodoxins, FldH and HmuF do not stabilize the FMN semiquinone but instead cycle between the FMN oxidized and hydroquinone states. We show that heme-loaded HmuF and heme-loaded FldH traffic heme to HmuW for degradation of the protoporphyrin ring. Both FldH and HmuF then catalyze multiple reductions of anaerobilin through hydride transfer from the FMN hydroquinone. The latter activity eliminates the aromaticity of anaerobilin and the electrophilic methylene group that was installed through HmuW turnover. Hence, HmuF provides a protected path for anaerobic heme catabolism, offering F. nucleatum a competitive advantage in the colonization of anoxic sites of the human body., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)- Published
- 2023
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21. Retrospective Evaluation of the Impact of a Geriatric Trauma Institute on Fragility Hip Fracture Patient Outcomes.
- Author
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Katrancha ED, Zipf J, Abrahams N, and Schroeder R
- Subjects
- Aged, Aged, 80 and over, Female, Geriatrics statistics & numerical data, Hip Fractures etiology, Hip Fractures physiopathology, Hospitalization statistics & numerical data, Humans, Male, Pennsylvania, Retrospective Studies, Geriatrics organization & administration, Hip Fractures complications, Patient Outcome Assessment
- Abstract
Background: Fragility hip fractures occur in the older than 65-year population at an alarming rate. It is estimated that 260,000 hip fractures occur annually. Patient outcomes following hip fractures are devastating. One of every 5 patients dies within 1 year of injury, and 1 of 3 remains in a nursing home for years after the injury. Published literature recommends an interdisciplinary approach to caring for hip-fractured patients and expediting surgery to improve outcomes., Purpose: The purpose of this study was to retrospectively evaluate the impact of the Geriatric Trauma Institute (GTI) on fragility hip fracture patient outcomes. Specific outcomes included length of stay (LOS), length of time from emergency department (ED) arrival to operating room (OR), complication rate, and discharge destination., Methods: This study is a single-center pre- and post-retrospective chart review. Data were collected using database queries within the hospital system. Pre-GTI (n = 326) patients older than 65 years with International Classification of Disease, Ninth Revision (ICD-9) codes 820.0-820.9 (hip fractures) admitted to either a primary care physician or orthopaedic surgeon service between April 1, 2011, and April 1, 2013, were compared with post-GTI (n = 245) patients older than 65 years with ICD-9 codes 820.0-820.9 (hip fractures) admitted to trauma services (GTI) between May 1, 2013, and May 1, 2015. Descriptive statistics including demographic data (age, sex) and comparison of outcomes (LOS, ED to OR time, complications, and disposition) across the groups using standard analysis of variance (ANOVA) and correlation techniques., Results: No statistical difference was found between groups for age, sex, or time from ED to OR pre- versus post-time period using one-way ANOVA, F(1,569) = 1.08, p = .30. The complication rate was calculated pre- and post-GTI and compared using the 2-proportion z-test. The difference between the pre-GTI group (16.6%; 54 of 326 patients) and the post-GTI group (9.4%; 23 of 245 patients) was statistically significant, p = .013. Mean LOS was statistically significantly higher in the pre-GTI group (M = 5) than in the post-GTI group (M = 5.2), U = 33,55, z = -3.32, p = .001. No statistical significance was found between pre- and postdischarge destination, χ(4) = .4.82, p = .307; likelihood ratio test, χ(4) = .5.19, p = .269., Conclusions: This retrospective pre- and post-GTI chart review demonstrates the effectiveness of a multidisciplinary team approach in decreasing complications and LOS for fragility hip-fractured patients. A team approach to the care of these patients improves outcomes and quality of life.
- Published
- 2017
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22. HGFA Is an Injury-Regulated Systemic Factor that Induces the Transition of Stem Cells into G Alert .
- Author
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Rodgers JT, Schroeder MD, Ma C, and Rando TA
- Subjects
- Adipocytes cytology, Adipocytes drug effects, Adipogenesis drug effects, Animals, Fibroblasts cytology, Fibroblasts drug effects, Kinetics, Mice, Inbred C57BL, Mice, Knockout, Muscle, Skeletal cytology, Serine Endopeptidases administration & dosage, Serum metabolism, Stem Cells drug effects, Stem Cells metabolism, Cell Cycle drug effects, Serine Endopeptidases pharmacology, Stem Cells cytology, Wound Healing drug effects
- Abstract
The activation of quiescent stem cells into the cell cycle is a key step in initiating the process of tissue repair. We recently reported that quiescent stem cells can transition into G
Alert , a cellular state in which they have an increased functional ability to activate and participate in tissue repair. However, the precise molecular signals that induce GAlert in stem cells have remained elusive. Here, we show that the injury-induced regulation of hepatocyte growth factor (HGF) proteolytic processing via the systemic protease, hepatocyte growth factor activator (HGFA), stimulates GAlert in skeletal muscle stem cells (MuSCs) and fibro-adipogenic progenitors (FAPs). We demonstrate that administering active HGFA to animals is sufficient to induce GAlert in stem cells throughout the body and to significantly accelerate the processes of stem cell activation and tissue repair. Our data suggest that factors that induce GAlert will have broad therapeutic applications for regenerative medicine and wound healing., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2017
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23. Infliximab in pediatric rheumatology patients: a retrospective analysis of infusion reactions and severe adverse events during 2246 infusions over 12 years.
- Author
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Aeschlimann FA, Hofer KD, Cannizzaro Schneider E, Schroeder S, Lauener R, and Saurenmann RK
- Subjects
- Adolescent, Antibodies, Monoclonal therapeutic use, Antirheumatic Agents therapeutic use, Child, Child, Preschool, Dyspnea chemically induced, Exanthema chemically induced, Female, Humans, Infliximab, Infusions, Intravenous adverse effects, Nausea chemically induced, Respiratory Sounds, Retrospective Studies, Urticaria chemically induced, Antibodies, Monoclonal adverse effects, Antirheumatic Agents adverse effects, Arthritis drug therapy, Uveitis drug therapy
- Abstract
Objective: To describe infusion reactions (IR) and severe adverse events (SAE) associated with infliximab (IFX) in pediatric patients with rheumatologic and ocular inflammatory diseases in a real-world setting., Methods: This is a retrospective chart review of all patients treated with IFX at the pediatric rheumatology division of a university hospital between October 2000 and December 2012., Results: A total of 2446 IFX infusions were given to 82 patients (72% female). IR occurred in 46 infusions (2%) of 14 patients (17%) after a mean IFX treatment time of 340 days (range 41-780); 9/14 patients (64%) experienced repeated IR. IR were classified as mild (26%), moderate (74%), or severe (0%). Indications for IFX were arthritis (60%), uveitis (20%), arthritis and uveitis (13%), and other inflammatory diseases (5%). The most common clinical symptoms were respiratory signs (72%), cutaneous manifestations (69%), and malaise (61%). In 6/14 patients (43%) with IR, IFX was discontinued: 4 patients because of repeated IR and 2 patients wished to stop treatment immediately following a mild IR. The other 8/14 patients (57%) received premedication with high-dose antihistamine (100%), corticosteroids (75%), and IFX dose increase (75%) and continued IFX treatment for a mean followup period of 146 weeks (range 26-537) after the first IR. We observed severe infections in 5/82 patients (6%); other SAE were rare., Conclusion: Mild and moderate IR occurred in 17% of our patients. Treatment with antihistamines and methylprednisolone, and increasing the IFX dose, allowed continued treatment despite IR in > 50% of patients. Other SAE were infrequent.
- Published
- 2014
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24. Making Drosophila lineage-restricted drivers via patterned recombination in neuroblasts.
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Awasaki T, Kao CF, Lee YJ, Yang CP, Huang Y, Pfeiffer BD, Luan H, Jing X, Huang YF, He Y, Schroeder MD, Kuzin A, Brody T, Zugates CT, Odenwald WF, and Lee T
- Subjects
- Animals, Cerebrum physiology, Drosophila physiology, Neural Stem Cells metabolism, Neural Stem Cells physiology, Receptors, Notch biosynthesis, Receptors, Notch genetics, Recombination, Genetic, Transgenes, Cell Lineage physiology, Cerebrum cytology, Drosophila cytology, Drosophila Proteins biosynthesis, Drosophila Proteins genetics, Genetic Techniques, Neural Stem Cells cytology
- Abstract
The Drosophila cerebrum originates from about 100 neuroblasts per hemisphere, with each neuroblast producing a characteristic set of neurons. Neurons from a neuroblast are often so diverse that many neuron types remain unexplored. We developed new genetic tools that target neuroblasts and their diverse descendants, increasing our ability to study fly brain structure and development. Common enhancer-based drivers label neurons on the basis of terminal identities rather than origins, which provides limited labeling in the heterogeneous neuronal lineages. We successfully converted conventional drivers that are temporarily expressed in neuroblasts, into drivers expressed in all subsequent neuroblast progeny. One technique involves immortalizing GAL4 expression in neuroblasts and their descendants. Another depends on loss of the GAL4 repressor, GAL80, from neuroblasts during early neurogenesis. Furthermore, we expanded the diversity of MARCM-based reagents and established another site-specific mitotic recombination system. Our transgenic tools can be combined to map individual neurons in specific lineages of various genotypes.
- Published
- 2014
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25. Clonal development and organization of the adult Drosophila central brain.
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Yu HH, Awasaki T, Schroeder MD, Long F, Yang JS, He Y, Ding P, Kao JC, Wu GY, Peng H, Myers G, and Lee T
- Subjects
- Animals, Brain cytology, Brain growth & development, Brain metabolism, Cell Lineage, Clone Cells cytology, Clone Cells metabolism, Drosophila melanogaster cytology, Drosophila melanogaster genetics, Female, Larva cytology, Larva genetics, Larva growth & development, Larva metabolism, Male, Microscopy, Confocal, Neural Stem Cells cytology, Neural Stem Cells metabolism, Neuropil cytology, Neuropil metabolism, Drosophila melanogaster growth & development, Drosophila melanogaster metabolism
- Abstract
Background: The insect brain can be divided into neuropils that are formed by neurites of both local and remote origin. The complexity of the interconnections obscures how these neuropils are established and interconnected through development. The Drosophila central brain develops from a fixed number of neuroblasts (NBs) that deposit neurons in regional clusters., Results: By determining individual NB clones and pursuing their projections into specific neuropils, we unravel the regional development of the brain neural network. Exhaustive clonal analysis revealed 95 stereotyped neuronal lineages with characteristic cell-body locations and neurite trajectories. Most clones show complex projection patterns, but despite the complexity, neighboring clones often coinnervate the same local neuropil or neuropils and further target a restricted set of distant neuropils., Conclusions: These observations argue for regional clonal development of both neuropils and neuropil connectivity throughout the Drosophila central brain., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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26. How to make stripes: deciphering the transition from non-periodic to periodic patterns in Drosophila segmentation.
- Author
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Schroeder MD, Greer C, and Gaul U
- Subjects
- Animals, Animals, Genetically Modified, DNA-Binding Proteins metabolism, Drosophila Proteins metabolism, Embryo, Nonmammalian anatomy & histology, Fushi Tarazu Transcription Factors metabolism, Genotype, Homeodomain Proteins metabolism, In Situ Hybridization, Nuclear Proteins metabolism, Periodicity, Transcription Factors metabolism, Body Patterning physiology, Drosophila embryology, Embryo, Nonmammalian embryology, Gene Expression Regulation, Developmental physiology
- Abstract
The generation of metameric body plans is a key process in development. In Drosophila segmentation, periodicity is established rapidly through the complex transcriptional regulation of the pair-rule genes. The 'primary' pair-rule genes generate their 7-stripe expression through stripe-specific cis-regulatory elements controlled by the preceding non-periodic maternal and gap gene patterns, whereas 'secondary' pair-rule genes are thought to rely on 7-stripe elements that read off the already periodic primary pair-rule patterns. Using a combination of computational and experimental approaches, we have conducted a comprehensive systems-level examination of the regulatory architecture underlying pair-rule stripe formation. We find that runt (run), fushi tarazu (ftz) and odd skipped (odd) establish most of their pattern through stripe-specific elements, arguing for a reclassification of ftz and odd as primary pair-rule genes. In the case of run, we observe long-range cis-regulation across multiple intervening genes. The 7-stripe elements of run, ftz and odd are active concurrently with the stripe-specific elements, indicating that maternal/gap-mediated control and pair-rule gene cross-regulation are closely integrated. Stripe-specific elements fall into three distinct classes based on their principal repressive gap factor input; stripe positions along the gap gradients correlate with the strength of predicted input. The prevalence of cis-elements that generate two stripes and their genomic organization suggest that single-stripe elements arose by splitting and subfunctionalization of ancestral dual-stripe elements. Overall, our study provides a greatly improved understanding of how periodic patterns are established in the Drosophila embryo.
- Published
- 2011
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27. Estrogen receptor-positive mammary tumorigenesis in TGFalpha transgenic mice progresses with progesterone receptor loss.
- Author
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Rose-Hellekant TA, Schroeder MD, Brockman JL, Zhdankin O, Bolstad R, Chen KS, Gould MN, Schuler LA, and Sandgren EP
- Subjects
- Animals, Base Sequence, DNA Primers, Female, Mice, Mice, Transgenic, RNA, Messenger genetics, Receptors, Estrogen genetics, Receptors, Progesterone genetics, Transforming Growth Factor alpha metabolism, Transgenes, Receptors, Estrogen metabolism, Receptors, Progesterone metabolism, Transforming Growth Factor alpha physiology
- Abstract
We characterized the novel NRL-transforming growth factor alpha (NRL-TGFalpha) transgenic mouse model in which growth factor - steroid receptor interactions were explored. The NRL promoter directs transgene expression to mammary ductal and alveolar cells and is nonresponsive to estrogen manipulations in vitro and in vivo. NRL-TGFalpha mice acquire proliferative hyperplasias as well as cystic and solid tumors. Quantitative transcript analysis revealed a progressive decrease in estrogen receptor alpha (ER) and progesterone receptor (PR) mRNA levels with tumorigenesis. However, ER protein was evident in all lesion types and in surrounding stromal cells using immunohistochemistry. PR protein was identified in normal epithelial cells and in very few cells of small epithelial hyperplasias, but never in stromal or tumor cells. Prophylactic ovariectomy significantly delayed tumor development and decreased incidence. Finally, while heterozygous (+/-) p53 mice did not acquire mammary lesions, p53+/- mice carrying the NRL-TGFalpha transgene developed ER negative/PR negative undifferentiated carcinomas. These data demonstrate that unregulated TGFalpha expression in the mammary gland leads to oncogenesis that is dependent on ovarian steroids early in tumorigenesis. Resulting tumors resemble a clinical phenotype of ER+/PR-, and when combined with a heterozygous p53 genotype, ER-/PR-.
- Published
- 2007
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28. Multiple kinase cascades mediate prolactin signals to activating protein-1 in breast cancer cells.
- Author
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Gutzman JH, Rugowski DE, Schroeder MD, Watters JJ, and Schuler LA
- Subjects
- Breast Neoplasms genetics, Cell Differentiation genetics, Cell Differentiation physiology, Cell Line, Tumor, Cell Proliferation, DNA-Binding Proteins metabolism, Dimerization, Female, Humans, MAP Kinase Signaling System genetics, Phosphorylation drug effects, Prolactin genetics, Prolactin pharmacology, Transcription Factor AP-1 genetics, Breast Neoplasms metabolism, Gene Expression Regulation, Neoplastic, MAP Kinase Signaling System physiology, Mitogen-Activated Protein Kinases metabolism, Prolactin physiology, Transcription Factor AP-1 metabolism
- Abstract
The importance of prolactin (PRL) in physiological proliferation and differentiation of the mammary gland, together with high levels of PRL receptors in breast tumors, the association of circulating PRL with incidence of breast cancer, and the recognition of locally produced PRL, point to the need for greater understanding of PRL actions in mammary disease. Although PRL has been shown to activate multiple kinase cascades in various target cells, relatively little is known of its signaling pathways in the mammary gland apart from the Janus kinase 2/ signal transducer and activator of transcription 5 pathway, particularly in tumor cells. Another potential effector is activating protein-1 (AP-1), a transcription complex that regulates processes essential for neoplastic progression, including proliferation, survival and invasion. We demonstrate that PRL activates AP-1 in MCF-7 cells, detectable at 4 h and sustained for at least 24 h. Although Janus kinase 2 and ERK1/2 are the primary mediators of PRL-induced signals, c-Src, phosphatidylinositol 3'-kinase, protein kinase C, and other MAPKs contribute to maximal activity. PRL activation of these pathways leads to increased c-Jun protein and phosphorylation, JunB protein, and phosphorylation of c-Fos, elevating the levels of AP-1 complexes able to bind DNA. These active AP-1 dimers may direct expression of multiple target genes, mediating some of PRL's actions in mammary disease.
- Published
- 2004
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29. Cross-species comparison significantly improves genome-wide prediction of cis-regulatory modules in Drosophila.
- Author
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Sinha S, Schroeder MD, Unnerstall U, Gaul U, and Siggia ED
- Subjects
- Algorithms, Animals, Conserved Sequence genetics, Drosophila melanogaster genetics, Evolution, Molecular, Gene Expression Regulation genetics, Genes, Insect genetics, Predictive Value of Tests, Species Specificity, Drosophila genetics, Genome, Transcription, Genetic genetics
- Abstract
Background: The discovery of cis-regulatory modules in metazoan genomes is crucial for understanding the connection between genes and organism diversity. It is important to quantify how comparative genomics can improve computational detection of such modules., Results: We run the Stubb software on the entire D. melanogaster genome, to obtain predictions of modules involved in segmentation of the embryo. Stubb uses a probabilistic model to score sequences for clustering of transcription factor binding sites, and can exploit multiple species data within the same probabilistic framework. The predictions are evaluated using publicly available gene expression data for thousands of genes, after careful manual annotation. We demonstrate that the use of a second genome (D. pseudoobscura) for cross-species comparison significantly improves the prediction accuracy of Stubb, and is a more sensitive approach than intersecting the results of separate runs over the two genomes. The entire list of predictions is made available online., Conclusion: Evolutionary conservation of modules serves as a filter to improve their detection in silico. The future availability of additional fruitfly genomes therefore carries the prospect of highly specific genome-wide predictions using Stubb.
- Published
- 2004
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30. Transcriptional control in the segmentation gene network of Drosophila.
- Author
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Schroeder MD, Pearce M, Fak J, Fan H, Unnerstall U, Emberly E, Rajewsky N, Siggia ED, and Gaul U
- Subjects
- Algorithms, Animals, Binding Sites, Body Patterning, Chromosome Mapping, Developmental Biology methods, Drosophila genetics, Evolution, Molecular, Genome, In Situ Hybridization, Models, Genetic, Multigene Family, Promoter Regions, Genetic, RNA, Messenger metabolism, Software, Species Specificity, Transcription Factors, Computational Biology methods, Drosophila melanogaster embryology, Drosophila melanogaster genetics, Gene Expression Regulation, Developmental, Transcription, Genetic
- Abstract
The segmentation gene network of Drosophila consists of maternal and zygotic factors that generate, by transcriptional (cross-) regulation, expression patterns of increasing complexity along the anterior-posterior axis of the embryo. Using known binding site information for maternal and zygotic gap transcription factors, the computer algorithm Ahab recovers known segmentation control elements (modules) with excellent success and predicts many novel modules within the network and genome-wide. We show that novel module predictions are highly enriched in the network and typically clustered proximal to the promoter, not only upstream, but also in intronic space and downstream. When placed upstream of a reporter gene, they consistently drive patterned blastoderm expression, in most cases faithfully producing one or more pattern elements of the endogenous gene. Moreover, we demonstrate for the entire set of known and newly validated modules that Ahab's prediction of binding sites correlates well with the expression patterns produced by the modules, revealing basic rules governing their composition. Specifically, we show that maternal factors consistently act as activators and that gap factors act as repressors, except for the bimodal factor Hunchback. Our data suggest a simple context-dependent rule for its switch from repressive to activating function. Overall, the composition of modules appears well fitted to the spatiotemporal distribution of their positive and negative input factors. Finally, by comparing Ahab predictions with different categories of transcription factor input, we confirm the global regulatory structure of the segmentation gene network, but find odd skipped behaving like a primary pair-rule gene. The study expands our knowledge of the segmentation gene network by increasing the number of experimentally tested modules by 50%. For the first time, the entire set of validated modules is analyzed for binding site composition under a uniform set of criteria, permitting the definition of basic composition rules. The study demonstrates that computational methods are a powerful complement to experimental approaches in the analysis of transcription networks.
- Published
- 2004
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31. Inhibition of prolactin (PRL)-induced proliferative signals in breast cancer cells by a molecular mimic of phosphorylated PRL, S179D-PRL.
- Author
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Schroeder MD, Brockman JL, Walker AM, and Schuler LA
- Subjects
- Animals, CHO Cells, Cell Count, Cell Division drug effects, Cell Division physiology, Cell Line, Tumor, Cricetinae, Cyclin D1 metabolism, DNA-Binding Proteins metabolism, Humans, Mitogen-Activated Protein Kinases metabolism, Molecular Mimicry, Phosphorylation, Prolactin metabolism, Receptors, Prolactin metabolism, STAT5 Transcription Factor, Signal Transduction physiology, Trans-Activators metabolism, Breast Neoplasms, Milk Proteins, Prolactin pharmacology, Signal Transduction drug effects
- Abstract
Posttranslational modifications of prolactin (PRL), including phosphorylation, vary with physiologic state and alter biologic activity. In light of the growing evidence for a role for PRL in proliferation in mammary cancer, we examined the ability of a mimic of phosphorylated human PRL, S179D-PRL, to initiate signals to several pathways in mammary tumor cells alone and in combination with unmodified PRL. Unmodified PRL employed multiple pathways to increase cellular proliferation and cyclin D1 levels in PRL-deficient MCF-7 cells. S179D-PRL was a weak agonist compared with unmodified PRL with regard to cellular proliferation, cyclin D1 levels, and phosphorylation of signal transducer and activator of transcription 5 and ERKs. However, S179D-PRL was a potent antagonist of unmodified PRL to these endpoints. In contrast to the reduced levels of the long isoform of the PRL receptor observed in response to a 3-d incubation with unmodified PRL, S179D-PRL up-regulated expression of this isoform, 4-fold. These studies support the utility of this mutant as a PRL antagonist to proliferative signals in mammary epithelial cells, including a potential role in breast cancer therapeutics.
- Published
- 2003
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32. Prolactin induces ERalpha-positive and ERalpha-negative mammary cancer in transgenic mice.
- Author
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Rose-Hellekant TA, Arendt LM, Schroeder MD, Gilchrist K, Sandgren EP, and Schuler LA
- Subjects
- Animals, Apoptosis, Bromodeoxyuridine pharmacology, Carrier Proteins genetics, Cell Division, Cell Lineage, Estrogen Receptor alpha, Female, Lipocalin-2, Lipocalins, Mammary Neoplasms, Animal etiology, Mice, Mice, Transgenic, Mitosis, Phenotype, Promoter Regions, Genetic, Rats, Reverse Transcriptase Polymerase Chain Reaction, Time Factors, Transgenes, Mammary Neoplasms, Animal metabolism, Prolactin physiology, Receptors, Estrogen metabolism
- Abstract
The role of prolactin in human breast cancer has been controversial. However, it is now apparent that human mammary epithelial cells can synthesize prolactin endogenously, permitting autocrine/paracrine actions within the mammary gland that are independent of pituitary prolactin. To model this local mammary production of prolactin (PRL), we have generated mice that overexpress prolactin within mammary epithelial cells under the control of a hormonally nonresponsive promoter, neu-related lipocalin (NRL). In each of the two examined NRL-PRL transgenic mouse lineages, female virgin mice display mammary developmental abnormalities, mammary intraepithelial neoplasias, and invasive neoplasms. Prolactin increases proliferation in morphologically normal alveoli and ducts, as well as in lesions. The tumors are of varied histotype, but papillary adenocarcinomas and adenosquamous neoplasms predominate. Neoplasms can be separated into two populations: one is estrogen receptor alpha (ERalpha) positive (greater than 15% of the cells stain for ERalpha), and the other is ERalpha- (<3%). ERalpha expression does not correlate with tumor histotype, or proliferative or apoptotic indices. These studies provide a mouse model of hormonally dependent breast cancer, and, perhaps most strikingly, a model in which some neoplasms retain ERalpha, as occurs in the human disease.
- Published
- 2003
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33. PRL activates the cyclin D1 promoter via the Jak2/Stat pathway.
- Author
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Brockman JL, Schroeder MD, and Schuler LA
- Subjects
- Amino Acid Sequence, Animals, CHO Cells, Cell Division drug effects, Consensus Sequence, Cricetinae, DNA Mutational Analysis, Epithelial Cells cytology, Epithelial Cells drug effects, Female, Humans, Janus Kinase 2, Molecular Sequence Data, STAT5 Transcription Factor, Signal Transduction, Tumor Cells, Cultured, Tumor Suppressor Proteins, Breast Neoplasms pathology, Cyclin D1 genetics, DNA-Binding Proteins physiology, Milk Proteins, Prolactin physiology, Promoter Regions, Genetic, Protein-Tyrosine Kinases physiology, Proto-Oncogene Proteins, Trans-Activators physiology
- Abstract
PRL promotes cell growth and differentiation in the mammary gland, which has implications for breast cancer as well as normal development. Our data demonstrate that PRL significantly increases proliferation of mammary carcinoma cells. PRL also increases cyclin D1 levels 2-fold, which can be inhibited by actinomycin D, suggesting that transcriptional increases in cyclin D1 are important. Using a defined Chinese hamster ovary cell model system, we demonstrate that the activity of a cyclin D1 promoter-luciferase construct increases after PRL treatment. Furthermore, this increase in promoter activity is predominantly mediated by the Jak2/Stat5 signaling pathway. The cyclin D1 promoter contains two consensus sequences for PRL-induced Stat binding (GAS sites). Disruption of Stat binding to the distal GAS site destroys PRL-induced promoter activity, whereas disruption of the proximal site has no effect. We have shown by EMSA that PRL induces Stat5a and 5b to bind to the distal GAS site, and immunoprecipitation and subsequent Western analysis of nuclear extracts from PRL-treated cells indicate that Stat5a and 5b can interact as a heterodimer in this system. These data suggest that cyclin D1 may be a target gene for PRL in normal lobuloalveolar development, as well as in the development and/or progression of mammary cancer.
- Published
- 2002
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34. PRL modulates cell cycle regulators in mammary tumor epithelial cells.
- Author
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Schroeder MD, Symowicz J, and Schuler LA
- Subjects
- Base Sequence, Cell Cycle Proteins genetics, Cyclin B drug effects, Cyclin B metabolism, Cyclin B1, Cyclin D1 drug effects, Cyclin D1 genetics, Cyclin D1 metabolism, Cyclin-Dependent Kinase Inhibitor p21, Cyclins drug effects, Cyclins metabolism, Enzyme Inhibitors pharmacology, Epidermal Growth Factor pharmacology, Epithelial Cells drug effects, Epithelial Cells metabolism, Epithelial Cells pathology, Female, Humans, Interferon-gamma genetics, Interferon-gamma metabolism, MAP Kinase Signaling System, Molecular Sequence Data, Oligonucleotides, Antisense pharmacology, Phosphorylation, Prolactin metabolism, Retinoblastoma Protein drug effects, Retinoblastoma Protein metabolism, Signal Transduction, Adenocarcinoma metabolism, Adenocarcinoma pathology, Breast Neoplasms metabolism, Breast Neoplasms pathology, Cell Cycle Proteins metabolism, Prolactin pharmacology
- Abstract
PRL is essential for normal lobulo-alveolar growth of the mammary gland and may contribute to mammary cancer development or progression. However, analysis of the mechanism of action of PRL in these processes is complicated by the production of PRL within mammary epithelia. To examine PRL actions in a mammary cell-specific context, we selected MCF-7 cells that lacked endogenous PRL synthesis, using PRL stimulation of interferon-gamma-activated sequence-related PRL response elements. Derived clones exhibited a greater proliferative response to PRL than control cells. To understand the mechanism, we examined, by Western analysis, levels of proteins essential for cell cycle progression as well as phosphorylation of retinoblastoma protein. The expression of cyclin D1, a critical regulator of the G1/S transition, was significantly increased by PRL and was associated with hyperphosphorylation of retinoblastoma protein at Ser(780). Cyclin B1 was also increased by PRL. In contrast, PRL decreased the Cip/Kip family inhibitor, p21, but not p16 or p27. These studies demonstrate that PRL can stimulate the cell cycle in mammary epithelia and identify specific targets in this process. This model system will enable further molecular dissection of the pathways involved in PRL-induced proliferation, increasing our understanding of this hormone and its interactions with other factors in normal and pathogenic processes.
- Published
- 2002
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- View/download PDF
35. Dysregulation of mammary Stats 1,3 and 5 and PRL receptors by overexpression of TGFalpha.
- Author
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Schroeder MD, Rose-Hellekant TA, Sandgren EP, and Schuler LA
- Subjects
- Animals, Breast chemistry, Breast growth & development, Cell Transformation, Neoplastic, DNA-Binding Proteins genetics, DNA-Binding Proteins metabolism, Female, Gene Expression Regulation, Mice, Mice, Transgenic, Phosphorylation, Pregnancy, Prolactin genetics, Protein Isoforms drug effects, Protein Isoforms genetics, RNA, Messenger metabolism, Receptors, Prolactin genetics, STAT1 Transcription Factor, STAT3 Transcription Factor, STAT5 Transcription Factor, Trans-Activators genetics, Trans-Activators metabolism, Transforming Growth Factor alpha metabolism, Breast metabolism, DNA-Binding Proteins drug effects, Milk Proteins, Receptors, Prolactin drug effects, Trans-Activators drug effects, Transforming Growth Factor alpha pharmacology
- Abstract
Mammary TGFalpha overexpression results in delayed involution and eventually mammary cancer in transgenic mice. We hypothesized that STATs and PRL receptors (PRLR), critical regulators of mammary function, are altered in these animals and may contribute to this phenotype. We examined these factors late in the first pregnancy (d.18) and during normal involution (d.4 post-lactation) in WAP-TGFalpha transgenic mice and non-transgenic controls. Long form PRLR mRNA in WAP-TGFalpha glands at both pregnant d.18 and d.4 post-lactation was significantly reduced compared to controls, and PRLR-S3 failed to rise during involution. Total and pTyr STAT 1,3,5a and 5b also were altered. STAT 3 was higher at both times in WAP-TGFalpha glands. STAT 5a and 5b were lower at late pregnancy, but higher post-lactation; however, pTyr(694) STAT 5 was abnormally low at both times. Thus overexpression of TGFalpha has direct or indirect effects on both STATs and PRL responsiveness in vivo, which may reflect mechanisms of TGFalpha-induced mammary epithelial abnormalities.
- Published
- 2001
- Full Text
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36. Casein kinase I alpha and alpha L: alternative splicing-generated kinases exhibit different catalytic properties.
- Author
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Zhang J, Gross SD, Schroeder MD, and Anderson RA
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Binding Sites, Casein Kinases, Catalysis, Cattle, DNA Primers, Exons, Glutathione Transferase biosynthesis, Introns, Isoenzymes biosynthesis, Isoenzymes chemistry, Kinetics, Molecular Sequence Data, Polymerase Chain Reaction, Protein Kinases biosynthesis, Protein Kinases chemistry, RNA Precursors metabolism, Rats, Recombinant Fusion Proteins biosynthesis, Recombinant Fusion Proteins chemistry, Recombinant Fusion Proteins metabolism, Sequence Homology, Amino Acid, Substrate Specificity, Alternative Splicing, Brain enzymology, Isoenzymes metabolism, Protein Kinases metabolism, Transcription, Genetic
- Abstract
Casein kinase I (CKI) is a family of serine/threonine protein kinases found in all eukaryotes examined to date. Here, the rat CKI isoforms alpha and alpha L were cloned and expressed in both eukaryotic and prokaryotic systems. Characterization of the genomic DNA flanking the exon unique to CKI alpha L demonstrated that CKI alpha and CKI alpha L arise by the alternative splicing of a common pre-mRNA molecule. To the best of our knowledge, the alpha L isoform is the only known active serine/threonine kinase to contain an insert within its catalytic domain. Tissue distribution of each splicing isoform was examined by RT-PCR, immunoprecipitation, and Western blotting. Both isoforms were expressed in all tissues tested but at different levels. Bacterially expressed CKI alpha isoforms were active and therefore biochemically characterized. CKI alpha and CKI alpha L proteins were demonstrated to have casein kinase I catalytic properties. More importantly, the recombinant isoform proteins exhibited differences in binding and activity toward common CKI substrates. These observations demonstrate that the alpha L insert within the kinase domain modulates substrate kinetics. These kinetic differences suggest that CKI alpha and CKI alpha L may perform different biological roles.
- Published
- 1996
- Full Text
- View/download PDF
37. Differential expression of DNA polymerase alpha in normal and transformed human fibroblasts.
- Author
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Srivastava VK, Schroeder MD, Miller SD, and Busbee DL
- Subjects
- Aged, Cell Division, Cell Line, Cell Line, Transformed, Fibroblasts enzymology, Humans, RNA, Messenger genetics, RNA, Messenger metabolism, DNA Polymerase II genetics
- Abstract
The expression of DNA polymerase alpha (pol alpha) was studied in human fibroblast lines W138 (fetal lung) and GM3529 (skin, established from a 66 yr old donor), and their Simian virus 40 (SV40) large tumor antigen (TAg)-transformed corollaries, 2RA and 2-1 respectively. Both SV40-transformed and pSV3.neo (SV40-derived plasmid)-transformed cells express TAg, a virally encoded protein not expressed by the normal parent cell lines. Northern blot hybridization studies showed increased recovery of pol alpha mRNA from transformed cells compared with normal cells. This increase was correlated with increased pol alpha mRNA transcription as determined by nuclear run-on assays. Northern blot analyses also showed an increase in the instability of translationally active pol alpha mRNA in transformed cells. The results suggest that TAg, in addition to its dsDNA binding, pol alpha binding, retinoblastoma protein binding and helicase activities, may be involved either directly or indirectly in regulation of the steady state mRNA levels of pol alpha at the transcriptional level in both fetal and aged donor-derived transformed fibroblasts.
- Published
- 1996
- Full Text
- View/download PDF
38. Parallel computation of genetic likelihoods using CRI-MAP, PVM, and a network of distributed workstations.
- Author
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Matise TC, Schroeder MD, Chiarulli DM, and Weeks DE
- Subjects
- Algorithms, Computer Communication Networks, Genetic Linkage, Software
- Abstract
We have developed a version of the CRI-MAP computer program for genetic likelihood computations that runs the FLIPS and ALL functions of CRI-MAP in parallel on a distributed network of workstations. The performance of CRI-MAP-PVM was assessed in several linkage analyses using the FLIPS option of CRI-MAP on a map of 85 microsatellite markers for human chromosome 1. These analyses showed excellent speedup and efficiency and low distribution overhead. In addition, we have adapted the MultiMap program for automated construction of linkage maps to use CRI-MAP-PVM. These improvements significantly reduce the time required to compare likelihoods of different marker orders. Thus, the construction of linkage maps can proceed in a more timely fashion, in keeping with recent advances in genotyping technology.
- Published
- 1995
- Full Text
- View/download PDF
39. Age-related changes in expression and activity of DNA polymerase alpha: some effects of dietary restriction.
- Author
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Srivastava VK, Miller S, Schroeder MD, Hart RW, and Busbee D
- Subjects
- Animals, Chromatography, DEAE-Cellulose, DNA Polymerase II biosynthesis, DNA Polymerase II genetics, Female, Liver enzymology, Mice, Mice, Inbred C57BL, Plasmids, RNA, Messenger metabolism, Aging metabolism, DNA Polymerase II metabolism, Energy Intake
- Abstract
DNA polymerase alpha (pol alpha) purified from human diploid fibroblasts (HDF) and from livers of C57BL/6N mice showed age-related decreases in: (1) mRNA levels; (2) the amount of enzyme isolated per cell; and (3) enzyme activity (HDF); as well as: a) the amount of enzyme isolated; b) the specific activity; and c) the enzyme fidelity (liver). Hepatic pol alpha from dietary restricted (DR) mice exhibited less of a decline in specific activity and copied synthetic DNA templates with relatively higher fidelity than did enzymes from animals fed ad libitum (AL). Pol alpha from fetal-derived HDF exhibited increased expression compared with aged donor-derived HDF, with both fetal and old cell pol alpha in normal cells being expressed at lower levels than in their transformed cell corollaries. Treatment of human pol alpha from aged donor-derived HDF with a pol alpha accessory protein isolated from log phase murine cells resulted in increased pol alpha binding of DNA and increased pol alpha activity. However, highly active pol alpha isolated from fetal-derived or transformed HDF, or from transformed murine cells, showed little or no activity enhancement in the presence of accessory protein. These data indicate that, as a function of increased age, there is a decrease in pol alpha expression and specific activity in HDF, as well as decreases in specific activity and fidelity of pol alpha in essentially amitotic murine hepatic tissues. Dietary restriction impedes the age-related declines in both activity and fidelity of hepatic pol alpha in mice. The data further indicate that transformation of slowly dividing HDF is associated with increased expression of pol alpha, but suggest that increased expression alone is not sufficient to explain the difference in polymerase activity levels between parental and transformed HDF. Lastly, the data suggest that interaction of pol alpha with an essential accessory protein may be altered as a function of age, an alteration that appears to be correlated with the decline in pol alpha DNA binding and specific activity.
- Published
- 1993
- Full Text
- View/download PDF
40. A comparison of DNA polymerase alpha from untransformed and SV40-transformed human fibroblasts.
- Author
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Srivastava VK, Schroeder MD, Miller SM, and Busbee DL
- Subjects
- Antigens, Polyomavirus Transforming metabolism, Blotting, Western, Cell Line, Cell Line, Transformed, Chromatography, DEAE-Cellulose, DNA metabolism, DNA Polymerase II antagonists & inhibitors, Fibroblasts microbiology, Hot Temperature, Humans, Substrate Specificity, Templates, Genetic, Cell Transformation, Viral, DNA Polymerase II metabolism, Fibroblasts enzymology, Simian virus 40 physiology
- Abstract
1. DNA polymerase alpha (pol alpha) isolated from Simian virus 40 (SV40)-transformed cells showed more than 3-fold higher specific activity than pol alpha from normal cells. The enzymes from untransformed and transformed cells also differed in molecular size, thermolability, sensitivity to inhibitors and specificity of template-primer utilization. 2. Western analysis using anti-Tag to probe both a crude cell homogenate and partially purified pol alpha from SV40 transformed cells showed multiple immunoreactive bands with different molecular sizes. 3. While alpha polymerases from both normal and transformed cells exhibited tightly associated primase activity, they showed different DNA binding affinities. 4. These data suggest that T antigen binding to pol alpha alters the initiation of DNA replication and/or the function of pol alpha in SV40-transformed cells, and that pol alpha from SV40-transformed human fibroblasts have different catalytic subunit characteristics than pol alpha from untransformed cells.
- Published
- 1993
- Full Text
- View/download PDF
41. Characterization of DNA polymerase alpha from untransformed and pSV3.neo-transformed human fibroblasts.
- Author
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Srivastava VK, Schroeder MD, and Busbee DL
- Subjects
- Aged, Antigens, Polyomavirus Transforming analysis, Antigens, Polyomavirus Transforming metabolism, Blotting, Western, Catalysis, Cell Division, Cell Line, Transformed, Cellulose analogs & derivatives, Cellulose metabolism, DNA metabolism, DNA Polymerase II antagonists & inhibitors, DNA Polymerase II chemistry, Humans, Molecular Weight, Templates, Genetic, Cell Transformation, Viral, DNA Polymerase II metabolism, Fibroblasts enzymology, Simian virus 40 immunology
- Abstract
1. The specific activity of DNA-polymerase alpha isolated from pSV3.neo-transformed cells was more than 9-fold higher than that of polymerase alpha from untransformed cells. 2. Western blot analysis, using anti-SV40 large T antigen, of both a crude cellular extract and of partially purified polymerase alpha from pSV3.neo-transformed cells revealed a single 76 kDa immunoreactive band not found in either crude extracts or partially purified enzyme from untransformed cells. 3. The alpha polymerases from untransformed and transformed cells differed in molecular size, sensitivity to various inhibitors, specificity of template-primer utilization, and binding affinity for DNA cellulose, but showed essentially no differences in Km or Vmax. 4. These data suggest that polymerase alpha isolated from pSV3.neo-transformed cells exhibits altered physical and catalytic characteristics compared with its untransformed cell counterpart, and that those alterations may be associated with increased replication of the genome in plasmid-transformed cells.
- Published
- 1993
- Full Text
- View/download PDF
42. A specific and sensitive bioassay for arginine-vasotocin: description, validation, and some applications in lower and higher vertebrates.
- Author
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Holder FC, Schroeder MD, Pollatz M, Guerné JM, Vivien-Roels B, Pévet P, Buijs RM, Dogterom J, and Meiniel A
- Subjects
- Amphibians, Animals, Aorta drug effects, Birds, Cricetinae, Fishes, Lampreys, Muscle Contraction drug effects, Pineal Gland analysis, Pituitary Gland, Posterior analysis, Rabbits, Radioimmunoassay, Rats, Reptiles, Species Specificity, Biological Assay methods, Vasotocin analysis
- Published
- 1982
- Full Text
- View/download PDF
43. Comparative immunohistochemical, radioimmunological and biological attempt to identify arginine-vasotocin (AVT) in the pineal gland of reptiles and fishes.
- Author
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Vivien-Roels B, Guerne JM, Holder FC, and Schroeder MD
- Subjects
- Animals, Biological Assay methods, Fluorescent Antibody Technique, Fresh Water, Radioimmunoassay methods, Fishes metabolism, Pineal Gland analysis, Reptiles metabolism, Vasotocin analysis
- Published
- 1979
- Full Text
- View/download PDF
44. A preliminary comparative immunohistochemical, radioimmunological, and biological study of arginine vasotocin (AVT) in the pineal gland and urophysis of some teleostei.
- Author
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Holder FC, Schroeder MD, Guerne JM, and Vivien-Roels B
- Subjects
- Animals, Biological Assay, Eels, Fishes, Fluorescent Antibody Technique, Histocytochemistry, Radioimmunoassay, Salmon, Species Specificity, Neurosecretory Systems analysis, Pineal Gland analysis, Vasotocin analysis
- Published
- 1979
- Full Text
- View/download PDF
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