Michael K. Obeng

Bio: Michael K. Obeng is an academic researcher from University of Texas Medical Branch. The author has contributed to research in topics: Protein catabolism & Hypermetabolism. The author has an hindex of 6, co-authored 7 publications receiving 1181 citations. Previous affiliations of Michael K. Obeng include Shriners Hospitals for Children.

Determinants of skeletal muscle catabolism after severe burn.

Abstract: Objective To determine which patient factors affect the degree of catabolism after severe burn. Background Data Catabolism is associated with severe burn and leads to erosion of lean mass, impaired wound healing, and delayed rehabilitation. Methods From 1996 to 1999, 151 stable-isotope protein kinetic studies were performed in 102 pediatric and 21 adult subjects burned over 20-99.5% of their total body surface area (TBSA). Patient demographics, burn characteristics, and hospital course variables were correlated with the net balance of skeletal muscle protein synthesis and breakdown across the leg. Data were analyzed sequentially and cumulatively through univariate and cross-sectional multiple regression. Results Increasing age, weight, and delay in definitive surgical treatment predict increased catabolism (P <.05). Body surface area burned increased catabolism until 40% TBSA was reached; catabolism did not consistently increase thereafter. Resting energy expenditure and sepsis were also strong predictors of net protein catabolism. Among factors that did not significantly correlate were burn type, pneumonia, wound contamination, and time after burn. From these results, the authors also infer that gross muscle mass correlates independently with protein wasting after burn. Conclusions Heavier, more muscular subjects, and subjects whose definitive surgical treatment is delayed are at the greatest risk for excess catabolism after burn. Sepsis and excessive hypermetabolism are also associated with protein catabolism.

Energy Expenditure and Caloric Balance After Burn: Increased Feeding Leads to Fat Rather Than Lean Mass Accretion

Abstract: A well-described array of metabolic derangements occurs after severe trauma or burn. This response includes hyperdynamic circulation, fever due to resetting of the hypothalamic temperature set point, immune deficiency, impaired wound healing, peripheral insulin resistance, alteration of hepatic protein synthesis, skeletal muscular protein catabolism, and elevated systemic energy expenditure. 1–9 During the flow phase after injury, survivors manifest a hyperdynamic circulation and begin to overtly display other systemic manifestations of global hypermetabolism. 10 Defects of both cellular and humoral immune function increase the likelihood of infection, hepatic protein synthesis shifts from storage and housekeeping proteins to acute phase response proteins, peripheral tissue insulin resistance with hyperglycemia occurs, and catabolism of proteins stores (predominantly skeletal muscle) leads to erosion of lean body mass. Fluxes of substrate fuels are altered with glucose, fat, and amino acids being supplied to the wound from hepatic gluconeogenesis, lipolysis, and auto-catabolized muscle protein. With the exception of circulatory physiologic parameters, these diverse systemic alterations are difficult to quantify. Associated with the hypermetabolic response is elevation in systemic energy expenditure. 11 This has been shown to correlate with the degree of muscle protein catabolism, impaired wound healing, and immune deficiency. 12-14 Resting energy expenditure as a correlate to total energy expenditure can be measured relatively easily at the bedside utilizing indirect calorimetry. Resting energy expenditure is determined from inspired and expired gases, measuring oxygen consumption and carbon dioxide production. It is noninvasive, reproducible, and immediately quantifiable (results are usually obtained within minutes). The general correlation between elevated energy expenditure and muscle catabolism has led to the notion that energy expenditure determines energy demand, which is required to offset catabolism. These demands, then, are met through the dietary delivery of calories. We hypothesize that muscle catabolism proceeds after severe burn regardless of caloric balance (caloric administration –measured energy expenditure). The goal of this study was twofold. First, we sought to determine the clinical relevance of elevated energy expenditure after burn, specifically whether elevated energy expenditure correlated with increased morbidity or mortality in the setting of severe burn. Second, we sought to determine whether energy expenditure could be used to define caloric demand to optimize attenuation of erosion of lean body mass. Our hypotheses were that 1) systemic energy expenditure is reflective of the degree of illness increasing to a point of exhaustion, after which decreases would correlate with mortality; and that 2) no optimal energy/caloric balance exists that abolishes catabolism of lean mass when at least 1.2 times the measured resting energy expenditure is delivered.

Mentoring in academic medicine: a systematic review.

Abstract: ContextMentoring, as a partnership in personal and professional growth and development, is central to academic medicine, but it is challenged by increased clinical, administrative, research, and other educational demands on medical faculty. Therefore, evidence for the value of mentoring needs to be evaluated.ObjectiveTo systematically review the evidence about the prevalence of mentorship and its relationship to career development.Data SourcesMEDLINE, Current Contents, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane Central Register of Controlled Trials, PsycINFO, and Scopus databases from the earliest available date to May 2006.Study Selection and Data ExtractionWe identified all studies evaluating the effect of mentoring on career choices and academic advancement among medical students and physicians. Minimum inclusion criteria were a description of the study population and availability of extractable data. No restrictions were placed on study methods or language.Data SynthesisThe literature search identified 3640 citations. Review of abstracts led to retrieval of 142 full-text articles for assessment; 42 articles describing 39 studies were selected for review. Of these, 34 (87%) were cross-sectional self-report surveys with small sample size and response rates ranging from 5% to 99%. One case-control study nested in a survey used a comparison group that had not received mentoring, and 1 cohort study had a small sample size and a large loss to follow-up. Less than 50% of medical students and in some fields less than 20% of faculty members had a mentor. Women perceived that they had more difficulty finding mentors than their colleagues who are men. Mentorship was reported to have an important influence on personal development, career guidance, career choice, and research productivity, including publication and grant success.ConclusionsMentoring is perceived as an important part of academic medicine, but the evidence to support this perception is not strong. Practical recommendations on mentoring in medicine that are evidence-based will require studies using more rigorous methods, addressing contextual issues, and using cross-disciplinary approaches.

Transcutaneous analyte sensor

Abstract: The present invention relates generally to systems and methods for measuring an analyte in a host. More particularly, the present invention relates to systems and methods for transcutaneous measurement of glucose in a host.

Systems and methods for processing analyte sensor data

Abstract: Systems and methods for applying time-dependent algorithmic compensation functions to data output from a continuous analyte sensor. Some embodiments determine a time since sensor implantation and/or whether a newly initialized sensor has been used previously.

Integrated delivery device for continuous glucose sensor

Abstract: Systems and methods for integrating a continuous glucose sensor, including a receiver, a medicament delivery device, and optionally a single point glucose monitor are provided. Manual integrations provide for a physical association between the devices wherein a user (for example, patient or doctor) manually selects the amount, type, and/or time of delivery. Semi-automated integration of the devices includes integrations wherein an operable connection between the integrated components aids the user (for example, patient or doctor) in selecting, inputting, calculating, or validating the amount, type, or time of medicament delivery of glucose values, for example, by transmitting data to another component and thereby reducing the amount of user input required. Automated integration between the devices includes integrations wherein an operable connection between the integrated components provides for full control of the system without required user interaction.