22 research outputs found

    Insulin-like growth factor 1 supplementation supports motor coordination and affects myelination in preterm pigs

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    IntroductionPreterm infants have increased risk of impaired neurodevelopment to which reduced systemic levels of insulin-like growth factor 1 (IGF-1) in the weeks after birth may play a role. Hence, we hypothesized that postnatal IGF-1 supplementation would improve brain development in preterm pigs, used as a model for preterm infants.MethodsPreterm pigs delivered by cesarean section received recombinant human IGF-1/IGF binding protein-3 complex (rhIGF-1/rhIGFBP-3, 2.25 mg/kg/day) or vehicle from birth to postnatal day 19. Motor function and cognition were assessed by monitoring of in-cage and open field activities, balance beam test, gait parameters, novel object recognition and operant conditioning tests. Collected brains were subject to magnetic resonance imaging (MRI), immunohistochemistry, gene expression analyses and protein synthesis measurements.ResultsThe IGF-1 treatment increased cerebellar protein synthesis rates (both in vivo and ex vivo). Performance in the balance beam test was improved by IGF-1 but not in other neurofunctional tests. The treatment decreased total and relative caudate nucleus weights, without any effects to total brain weight or grey/white matter volumes. Supplementation with IGF-1 reduced myelination in caudate nucleus, cerebellum, and white matter regions and decreased hilar synapse formation, without effects to oligodendrocyte maturation or neuron differentiation. Gene expression analyses indicated enhanced maturation of the GABAergic system in the caudate nucleus (decreased NKCC1:KCC2 ratio) with limited effects in cerebellum or hippocampus.ConclusionSupplemental IGF-1 during the first three weeks after preterm birth may support motor function by enhancing GABAergic maturation in the caudate nucleus, despite reduced myelination. Supplemental IGF-1 may support postnatal brain development in preterm infants, but more studies are required to identify optimal treatment regimens for subgroups of very or extremely preterm infants

    Insulin-Like Growth Factor-1 Supplementation Promotes Brain Maturation in Preterm Pigs

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    Very preterm infants show low levels of insulin-like growth factor-1 (IGF-1), which is associated with postnatal growth restriction and poor neurologic outcomes. It remains unknown whether supplemental IGF-1 may stimulate neurode-velopment in preterm neonates. Using cesarean-delivered preterm pigs as a model of preterm infants, we investi-gated the effects of supplemental IGF-1 on motor function and on regional and cellular brain development. Pigs were treated with 2.25 mg/kg/d recombinant human IGF-1/IGF binding protein-3 complex from birth until day 5 or 9 before the collection of brain samples for quantitative immunohistochemistry (IHC), RNA sequencing, and quantitative PCR analyses. Brain protein synthesis was measured using in vivo labeling with [2H5] phenylalanine. We showed that the IGF-1 receptor was widely distributed in the brain and largely coexisted with immature neurons. Region-spe-cific quantification of IHC labeling showed that IGF-1 treatment promoted neuronal differentiation, increased subcorti-cal myelination, and attenuated synaptogenesis in a region-dependent and time-dependent manner. The expression levels of genes involved in neuronal and oligodendrocyte maturation, and angiogenic and transport functions were al-tered, reflecting enhanced brain maturation in response to IGF-1 treatment. Cerebellar protein synthesis was increased by 19% at day 5 and 14% at day 9 after IGF-1 treatment. Treatment had no effect on Iba1+ microglia or regional brain weights and did not affect motor development or the expression of genes related to IGF-1 signaling. In conclusion, the data show that supplemental IGF-1 promotes brain maturation in newborn preterm pigs. The results provide further support for IGF-1 supplementation therapy in the early postnatal period in preterm infants

    North American Neuromodulation Society Educational Curriculum for Intrathecal Drug Delivery Systems Implantation and Management

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    OBJECTIVES: Intrathecal drug delivery systems (IDDSs) are used for the treatment of pain and spasticity. A wide range of educational criteria exist for these devices. The North American Neuromodulation Society (NANS) Education Committee developed a comprehensive IDDS curriculum to function as a standard for physician graduate education and assessment through training and into practice. MATERIAL AND METHODS: A multidisciplinary and diverse task force gathered by the NANS Education Committee met in person and virtually over several sessions and developed an IDDS curriculum modeling their previous work on spinal cord stimulation and following the Accreditation Council for Graduate Medical Education (ACGME) Milestones. There were iterative revisions and adaptations to the curriculum, and the final version was approved by the NANS Board of Directors. RESULTS: The curriculum was developed with distinction between implanting physicians and managing physician and physicians who perform both tasks. There is a lateral temporal progression from early learner to practitioner, with advanced learner in the middle. In addition, there is a modular vertical organization that divides the curriculum into the six educational competencies outlined by the ACGME. CONCLUSION: A comprehensive, modular, graduated, and segmented educational curriculum for IDDSs was developed by NANS. We propose the curriculum to be the standard for guidance and assessment of trainees and physicians pursuing training in implanting or managing IDDSs

    North American Neuromodulation Society Educational Curriculum for Intrathecal Drug Delivery Systems Implantation and Management.

    No full text
    OBJECTIVES: Intrathecal drug delivery systems (IDDSs) are used for the treatment of pain and spasticity. A wide range of educational criteria exist for these devices. The North American Neuromodulation Society (NANS) Education Committee developed a comprehensive IDDS curriculum to function as a standard for physician graduate education and assessment through training and into practice. MATERIAL AND METHODS: A multidisciplinary and diverse task force gathered by the NANS Education Committee met in person and virtually over several sessions and developed an IDDS curriculum modeling their previous work on spinal cord stimulation and following the Accreditation Council for Graduate Medical Education (ACGME) Milestones. There were iterative revisions and adaptations to the curriculum, and the final version was approved by the NANS Board of Directors. RESULTS: The curriculum was developed with distinction between implanting physicians and managing physician and physicians who perform both tasks. There is a lateral temporal progression from early learner to practitioner, with advanced learner in the middle. In addition, there is a modular vertical organization that divides the curriculum into the six educational competencies outlined by the ACGME. CONCLUSION: A comprehensive, modular, graduated, and segmented educational curriculum for IDDSs was developed by NANS. We propose the curriculum to be the standard for guidance and assessment of trainees and physicians pursuing training in implanting or managing IDDSs

    Whom Should We Profile? Examining Diabetes Care Practice Variation among Primary Care Providers, Provider Groups, and Health Care Facilities

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    OBJECTIVE: To evaluate the amount of variation in diabetes practice patterns at the primary care provider (PCP), provider group, and facility level, and to examine the reliability of diabetes care profiles constructed using electronic databases. DATA SOURCES/STUDY SETTING: Clinical and administrative data obtained from the electronic information systems at all facilities in a Department of Veterans Affairs' (VA) integrated service network for a study period of October 1997 through September 1998. STUDY DESIGN: This is a cohort study. The key variables of interest are different types of diabetes quality indicators, including measures of technical process, intermediate outcomes, and resource use. DATA COLLECTION/EXTRACTION METHODS: A coordinated registry of patients with diabetes was constructed by integrating laboratory, pharmacy, utilization, and primary care provider data extracted from the local clinical information system used at all VA medical centers. The study sample consisted of 12,110 patients with diabetes, 258 PCPs, 42 provider groups, and 13 facilities. PRINCIPAL FINDINGS: There were large differences in the amount of practice variation across levels of care and for different types of diabetes care indicators. The greatest amount of variance tended to be attributable to the facility level. For process measures, such as whether a hemoglobin A1c was measured, the facility and PCP effects were generally comparable. However, for three resource use measures the facility effect was at least six times the size of the PCP effect, and for intermediate outcome indicators, such as hyperlipidemia, facility effects ranged from two to sixty times the size of the PCP level effect. A somewhat larger PCP effect was found (5 percent of the variation) when we examined a “linked” process–outcome measure (linking hyperlipidemia and treatment with statins). When the PCP effect is small (i.e., 2 percent), a panel of two hundred diabetes patients is needed to construct profiles with 80 percent reliability. CONCLUSIONS: Little of the variation in many currently measured diabetes care practices is attributable to PCPs and, unless panel sizes are large, PCP profiling will be inaccurate. If profiling is to improve quality, it may be best to focus on examining facility-level performance variations and on developing indicators that promote specific, high-priority clinical actions
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