Assessing Neuronal Interactions of Cell Assemblies during General Anesthesia

Understanding the way in which groups of cortical neurons change their individual and mutual firing activity during the induction of general anesthesia may improve the safe usage of many anesthetic agents. Assessing neuronal interactions within cell assemblies during anesthesia may be useful for understanding the neural mechanisms of general anesthesia. Here, a point process generalized linear model (PPGLM) was applied to infer the functional connectivity of neuronal ensembles during both baseline and anesthesia, in which neuronal firing rates and network connectivity might change dramatically. A hierarchical Bayesian modeling approach combined with a variational Bayes (VB) algorithm is used for statistical inference. The effectiveness of our approach is evaluated with synthetic spike train data drawn from small and medium-size networks (consisting of up to 200 neurons), which are simulated using biophysical voltage-gated conductance models. We further apply the analysis to experimental spike train data recorded from rats' barrel cortex during both active behavior and isoflurane anesthesia conditions. Our results suggest that that neuronal interactions of both putative excitatory and inhibitory connections are reduced after the induction of isoflurane anesthesia.National Institutes of Health (U.S.) (NIH Grants DP1-OD003646

Transplant Outcomes for Children with Hypodiploid Acute Lymphoblastic Leukemia: The Cibmtr Experience

Cincinnati Childrens Hosp Med Ctr, Cincinnati, OH 45229 USAMed Coll Wisconsin, CIBMTR, Milwaukee, WI 53226 USAMed Coll Wisconsin, Milwaukee, WI 53226 USAInst Oncol Pediat, Sao Paulo, BrazilUniv Michigan, Ann Arbor, MI 48109 USAUniv S Florida, All Childrens Hosp, St Petersburg, FL 33701 USAWeb of Scienc

Micro-drive Array for Chronic in vivo Recording: Tetrode Assembly

The tetrode, a bundle of four electrodes, has proven to be a valuable tool for the simultaneous recording of multiple neurons in-vivo. The differential amplitude of action potential signatures over the channels of a tetrode allows for the isolation of single-unit activity from multi-unit signals. The ability to precisely control the stereotaxic location and depth of the tetrode is critical for studying coordinated neural activity across brain regions. In combination with a micro-drive array, it is possible to achieve precise placement and stable control of many tetrodes over the course of days to weeks. In this protocol, we demonstrate how to fabricate and condition tetrodes using basic tools and materials, install the tetrodes into a multi-drive tetrode array for chronic in-vivo recording in the rat, make ground wire connections to the micro-drive array, and attach a protective cone onto the micro-drive array in order to protect the tetrodes from physical contact with the environment

Total and Active Rabbit Antithymocyte Globulin (rATG;Thymoglobulin®) Pharmacokinetics in Pediatric Patients Undergoing Unrelated Donor Bone Marrow Transplantation

AbstractRabbit antithymocyte globulin (rATG; Thymoglobulin®) is currently used to prevent or treat graft-versus-host disease (GVHD) during hematopoietic stem cell transplantation (HSCT). The dose and schedule of rATG as part of the preparative regimen for unrelated donor (URD) bone marrow transplantation (BMT) have not been optimized in pediatric patients. We conducted a prospective study of 13 pediatric patients with hematologic malignancies undergoing URD BMT at St. Jude Children's Research Hospital from October 2003 to March 2005, to determine the pharmacokinetics and toxicities of active and total rATG. The conditioning regimen comprised total body irradiation (TBI), thiotepa, and cyclophosphamide (Cy); cyclosporine (CsA) and methotrexate (MTX) were administered as GVHD prophylaxis. Patients received a total dose of 10 mg/kg rATG, and serial blood samples were assayed for total rATG by enzyme linked immunosorbent assay (ELISA) and active rATG by florescein activated cell sorting (FACS). We found that our weight-based dosing regimen for rATG was effective and well tolerated by patients. The half-lives of total and active rATG were comparable to those from previous studies, and despite high doses our patients had low maximum concentrations of active and total rATG. There were no occurrences of grade iii-iv GVHD even in patients having low peak rATG levels, and the overall incidence of grade II GVHD was only 15%. None of the patients had serious infections following transplantation. These data support the use of a 10 mg/kg dose of rATG in children with hematologic malignancies because it can be administered without increasing the risk of graft rejection, or serious infection in pediatric patients with a low rate of GVHD. These conclusions may not apply to patients with nonmalignant disorders

Explorations, Vol. 6, No. 1

Cover: Panthera pardus, Chui in Kiswatuli, was photographed by Dr. Linda Karbonit ar Dr. James A. Sherburne in Serengeti National Park, Tanzania. Karbonit was accompanying Sherburne who was working on the design and development of the University of Maine, U.S. Fish and Wildlife Service, assistance program in wildlife training and conservation education to Tanzania’s National Parks. Sherburne, who has worked in Tanzania for several years, was there most recently in 1988 and 1989 working on the parks project. He serves as the Director of International Natural Resources and Agricultural Programs at the University of Maine. Articles include: Research and Economic Development: from the U.S. Senate Statement, December 22, 1989, by Sen. George J. Mitchell Politics and Research: Providing a Key for Economic Development, by Sen. William S. Cohen. Publisher’s Perspective, by Gregory N. Brown, Vice President, Research and Public Service What’s EPSCoR? Editorial Reflections, by Carole J. Bombard Past and Present: Marine Geologists Explore the Old and Teach the Young, by Daniel Belknap and Joseph Kelley High Biological Productivity: Salt Marshes, by Mark E. Wood Barrier Beaches, by William Duffy Sediment Budgets & Bluff Slump, by Rebecca Smith Coastal Environments and Change, by Andrew Walsh Mapping What You Can\u27t See, by Donald Robbins Casco Bay: Sea Level and the Shoreline, by Bradley W.B. Hay Christmas at Sea, by Molly Horvath A Short Course and the Local Economy, by Richard Hale and James Philp Dr. Bernard Lown: Alumnus Receives Golden Door Award The Sky is Falling . . . well, maybe, by Carole J. Bombard A Growing Interest in Timberland, by Robert A. Strong and Bret P. Vicar

One-Antigen Mismatched Related versus HLA-Matched Unrelated Donor Hematopoietic Stem Cell Transplantation in Adults with Acute Leukemia: Center for International Blood and Marrow Transplant Research Results in the Era of Molecular HLA Typing

Approximately 13% of patients lacking an HLA-identical sibling have a one-antigen–mismatched related donor (MMRD). Historically, outcomes from the use of a one-antigen MMRD were considered equivalent to those from the use of a matched unrelated donor (UD). Recent improvements in UD stem cell transplantation (SCT) resulting from better molecular HLA matching justifies investigating whether UD should be preferred over MMRD in adult patients with acute leukemia. Here, we compared the outcomes of MMRD (n = 89) and HLA-A, -B, -C, and -DRB1 allele–matched UD (n = 700) SCT reported to the Center for International Blood and Marrow Transplant Research between 1995 and 2005. The patients underwent transplantation for acute myelogenous leukemia or acute lymphoblastic leukemia in first or second complete remission. Donor type was not associated with hematologic recovery. Univariate and multivariate comparisons of MMRD versus HLA-matched UD transplants showed no statistically significant differences in overall survival, disease-free survival, treatment-related mortality, relapse, or 100-day grade III-IV acute graft-versus-host disease (GVHD). MMRD SCT was associated with a lower rate of chronic GVHD at 1 year (35% vs 47%; P = .03), which was confirmed by multivariate analysis (relative risk, 0.58; 95% confidence interval, 0.39-0.85; P < .01). According to our data, HLA-matched UD and MMRD SCT are associated with comparable survival. Given that less chronic GVHD was observed in the MMRD transplantations, this option, when available, remains the first choice in patients with acute leukemia without an HLA-identical sibling in need of allogeneic SCT

Diversity of Pol IV Function Is Defined by Mutations at the Maize rmr7 Locus

Mutations affecting the heritable maintenance of epigenetic states in maize identify multiple small RNA biogenesis factors including NRPD1, the largest subunit of the presumed maize Pol IV holoenzyme. Here we show that mutations defining the required to maintain repression7 locus identify a second RNA polymerase subunit related to Arabidopsis NRPD2a, the sole second largest subunit shared between Arabidopsis Pol IV and Pol V. A phylogenetic analysis shows that, in contrast to representative eudicots, grasses have retained duplicate loci capable of producing functional NRPD2-like proteins, which is indicative of increased RNA polymerase diversity in grasses relative to eudicots. Together with comparisons of rmr7 mutant plant phenotypes and their effects on the maintenance of epigenetic states with parallel analyses of NRPD1 defects, our results imply that maize utilizes multiple functional NRPD2-like proteins. Despite the observation that RMR7/NRPD2, like NRPD1, is required for the accumulation of most siRNAs, our data indicate that different Pol IV isoforms play distinct roles in the maintenance of meiotically-heritable epigenetic information in the grasses

Late Effects in Hematopoietic Cell Transplant Recipients with Acquired Severe Aplastic Anemia: A Report from the Late Effects Working Committee of the Center for International Blood and Marrow Transplant Research

With improvements in hematopoietic cell transplant (HCT) outcomes for severe aplastic anemia (SAA), there is a growing population of SAA survivors after HCT. However, there is a paucity of information regarding late effects that occur after HCT in SAA survivors. This study describes the malignant and nonmalignant late effects in survivors with SAA after HCT. A descriptive analysis was conducted of 1718 patients post-HCT for acquired SAA between 1995 and 2006 reported to the Center for International Blood and Marrow Transplant Research (CIBMTR). the prevalence and cumulative incidence estimates of late effects are reported for 1-year HCT survivors with SAA. of the HCT recipients, 1176 (68.5%) and 542 (31.5%) patients underwent a matched sibling donor (MSD) or unrelated donor (URD) HCT, respectively. the median age at the time of HCT was 20 years. the median interval from diagnosis to transplantation was 3 months for MSD HCT and 14 months for URD HCT. the median follow-up was 70 months and 67 months for MSD and URD HCT survivors, respectively. Overall survival at I year, 2 years, and 5 years for the entire cohort was 76% (95% confidence interval [CI]: 74-78), 73% (95% CI: 71-75), and 70% (95% CI: 68-72). Among 1-year survivors of MSD HCT, 6% had 1 late effect and 1% had multiple late effects. for 1-year survivors of URD HCT, 13% had 1 late effect and 2% had multiple late effects. Among survivors of MSD HCT, the cumulative incidence estimates of developing late effects were all <3% and did not increase over time. in contrast, for recipients of URD HCT, the cumulative incidence of developing several late effects exceeded 3% by 5 years: gonadal dysfunction 10.5% (95% CI: 7.3-14.3), growth disturbance 7.2% (95% CI: 4.4-10.7), avascular necrosis 6.3% (95% CI: 3.6-9.7), hypothyroidism 5.5% (95% CI: 2.8-9.0), and cataracts 5.1% (95% CI: 2.9-8.0). Our results indicated that all patients undergoing HCT for SAA remain at risk for late effects, must be counseled about, and should be monitored for late effects for the remainder of their lives.Public Health Service Grant from the National Cancer InstituteNational Heart, Lung, and Blood InstituteNational Institute of Allergy and Infectious DiseasesNational Cancer InstituteHealth Resources and Services Administration/Department of Health and Human ServicesOffice of Naval ResearchAllosAmgenAngioblastChildrens Hosp Orange Cty, Dept Hematol, Orange, CA 92668 USACIBMTR Med Coll Wisconsin, Dept Biostat, Milwaukee, WI USAMed Coll Wisconsin, CIBMTR Stat Ctr, Milwaukee, WI 53226 USAKing Faisal Specialist Hosp & Res Ctr, Dept Oncol, Riyadh 11211, Saudi ArabiaNew York Med Coll, Dept Pediat Hematol Oncol & Stem Cell Transplanta, Valhalla, NY 10595 USAStemcyte, Covina, CA USADana Farber Canc Inst, Dept Pediat Oncol, Boston, MA 02115 USAUniv Florida, Dept Hematol Oncol, Gainesville, FL USAPrincess Margaret Hosp, Dept Med, Toronto, ON M4X 1K9, CanadaUniv S Florida, All Childrens Hosp, Dept Pediat Hematol & Oncol, St Petersburg, FL 33701 USAUniv Basel Hosp, Dept Hematol, CH-4031 Basel, SwitzerlandOregon Hlth & Sci Univ, Dept Hematol & Oncol, Portland, OR 97201 USAChildrens Natl Med Ctr, Dept Blood & Marrow Transplantat, Washington, DC 20010 USABaylor Coll Med, Ctr Cell Therapy, Dept Hematol & Oncol, Houston, TX 77030 USAUniv N Carolina Hosp, Dept Pediat, Chapel Hill, NC USAUniv Hosp Case, Med Ctr, Dept Med, Cleveland, OH USAUniv Arkansas Med Sci, Dept Hematol & Oncol, Little Rock, AR 72205 USACincinnati Childrens Hosp Med Ctr, Dept Bone Marrow Transplantat & Immune Deficiency, Cincinnati, OH USATufts Med Ctr, Dept Med & Pediat, Boston, MA USAUniv S Florida, Coll Med, H Lee Moffitt Canc Ctr & Res Inst, Dept Hematol & Oncol, Tampa, FL 33612 USAFlorida Ctr Cellular Therapy, Dept Med, Orlando, FL USAUniv Fed Parana, Dept Bone Marrow Transplantat, BR-80060000 Curitiba, Parana, BrazilVanderbilt Univ, Med Ctr, Dept Med, Nashville, TN USAInst Oncol Pediat, Dept Pediat, São Paulo, BrazilFred Hutchinson Canc Res Ctr, Dept Clin Res & Transplantat, Seattle, WA 98104 USAMt Sinai Med Ctr, Dept Bone Marrow & Stem Cell Transplantat, New York, NY 10029 USAUniv N Carolina Hosp, Dept Hematol & Oncol, Chapel Hill, NC USAUniv Manitoba, CancerCare Manitoba, Dept Manitoba Blood & Marrow Transplant Program, Winnipeg, MB, CanadaKarolinska Univ Hosp, Ctr Allogene Stem Cell Transplantat, Dept Pediat, Stockholm, SwedenLouisiana State Univ, Hlth Sci Ctr, Childrens Hosp, Dept Pediat, New Orleans, LA USADept Natl Marrow Donor Program, Minneapolis, MN USAPublic Health Service Grant from the National Cancer Institute: U24-CA76518National Heart, Lung, and Blood Institute: 5U01HL069294Office of Naval Research: N00014-06-1-0704Office of Naval Research: N00014-08-1-0058HHSH234200637015CWeb of Scienc