Protective effects of oral creatine supplementation on spinal cord injury in rats

STUDY DESIGN: To evaluate a potential protective effect of increased creatine levels in spinal cord injury (SCI) in an animal model. OBJECTIVES: Acute SCI initiates a series of cellular and molecular events in the injured tissue leading to further damage in the surrounding area. This secondary damage is partly due to ischemia and a fatal intracellular loss of energy. Phospho-creatine in conjunction with the creatine kinase isoenzyme system acts as a potent intracellular energy buffer. Oral creatine supplementation has been shown to elevate the phospho-creatine content in brain and muscle tissue, leading to neuroprotective effects and increased muscle performance. SETTING: Zurich, Switzerland. METHODS: Twenty adult rats were fed for 4 weeks with or without creatine supplemented nutrition before undergoing a moderate spinal cord contusion. RESULTS: Following an initial complete hindlimb paralysis, rats of both groups substantially recovered within 1 week. However, creatine fed animals scored 2.8 points better than the controls in the BBB open field locomotor score (11.9 and 9.1 points respectively after 1 week; P=0.035, and 13 points compared to 11.4 after 2 weeks). The histological examination 2 weeks after SCI revealed that in all rats a cavity had developed which was comparable in size between the groups. In creatine fed rats, however, a significantly smaller amount of scar tissue surrounding the cavity was found. CONCLUSIONS: Thus creatine treatment seems to reduce the spread of secondary injury. Our results favour a pretreatment of patients with creatine for neuroprotection in cases of elective intramedullary spinal surgery. Further studies are needed to evaluate the benefit of immediate creatine administration in case of acute spinal cord or brain injury.     

Neurokinin A level in hypoxic–ischemic encephalopathy

Background: The present study was performed to investigate the effect of neonatal hypoxic–ischemic encephalopathy (HIE) on the neurotransmitter neurokinin A (NKA) and determine its relation to the severity of neonatal hypoxia. Methods: Eighteen neonates suffering from HIE were compared to 10 clinically healthy full‐term neonates acting as the control group. Maternal history of each neonate was collected, then deliveries were attended, resuscitation details including the Apgar score and thorough clinical examination of the neonates were performed. Routine laboratory work‐up was done for the enrolled neonates, including complete blood count and C‐reactive protein as well as estimation of NKA by enzyme‐linked immunosorbent assay in the cord blood and after clinical stabilization. Results: NKA was significantly lower in HIE patients compared to the controls at delivery with improvement in the follow‐up sample. Additionally, the maximum decrease was detected in the neonates who suffered severe hypoxia compared to those who suffered mild hypoxia. Significant positive correlations were demonstrated between NKA at birth and Apgar scores at the 10th and 15th min. Regression showed that stage of HIE was the strongest determinant factor for the level of NKA at birth. Conclusion: NKA levels are decreased in HIE and this is more profound in the severe degrees of hypoxia compared to the mild ones. This emphasizes its role in pathogenesis of HIE and further proves that an imbalance in the central neuropeptide system results from HIE in the neonatal period.     

Model of the viscoelastic behaviour of skin in vivo and study of anisotropy

BACKGROUND: The single-axis extension test is relatively little used to study the mechanical properties of human skin in vivo. A campaign of tests was carried out with an original, modern machine developed in our laboratory. It can perform extension or compression tests using servo-controlled position or force in different directions. The load can either be of the extension or monotonous compression type, creep or relaxation. The results obtained were used to develop a viscoelastic model. The elastic modulus calculated helps us to determine the main directions of anisotropy on the forearm. METHODS: We use a new in vivo single-axis extension machine (patent no. FR03/09220 application in progress). With it, we can carry out monotonous, creep and relaxation tests on the forearm. An associated finite elements model enables conversion to the intrinsic parameters of the skin under stress and strain from external stress applied in force and displacement. From the tests, we can propose a viscoelastic model and the identification of his parameters. We carried out tests in four directions with respect to the axis of the forearm of 63 people of different ages. The present report is limited to a brief presentation of the experimental set-up used, and a more complete presentation of the viscoelastic model and how it is defined and also the work on the anisotropy in the elastic domain. RESULTS: The viscoelastic model proposed has only four intrinsic parameters: elasticity parameters E(e) and E(ve) and viscosity parameters epsilon(ve) and A. Skin being considered as orthotropic, we were able to determine the average main direction of 63 people, which is of 5.33+/-5.78 around the longitudinal axis of the arm. An average modulus E(1) (ave)=6.57E(5) (Pa) can be found in the direction close to the axis of the arm and E(2) (ave)=1.30E(5) (Pa) in the perpendicular direction and a G(12)=1.32E(5) (Pa) shear modulus. CONCLUSIONS: The parameters obtained with the viscoelastic model are independent of the type of load, the same coefficients enable a correct representation in creep and relaxation tests. The main directions vary from one person to another, Young's modulus in these directions could be an indicator for dermatologists and cosmeticians.     

The deep South network for cancer control: eliminating cancer disparities through community-academic collaboration

African Americans have a substantially increased mortality rate compared to Whites in many cancers, including breast and cervix. The Deep South Network for Cancer Control (the Network) was established to develop sustainable community infrastructure to promote cancer awareness, enhance participation of African Americans and other special populations in clinical trials, recruit and train minority investigators, and develop and test innovative community-based cancer control measures to eliminate cancer mortality disparities in special populations. This article describes the steps necessary to form the network and the process and activities required to establish it as an effective infrastructure for eliminating disparities between Whites and African Americans in the United States.     

Generation of islet-like hormone-producing cells in vitro from adult human pancreas

Transplantation of pancreatic islets can provide long-lasting insulin independence for diabetic patients, but the current islet supply is limited. Here we describe a new in vitro system that utilizes adult human pancreatic islet-enriched fractions to generate hormone-producing cells over 3-4 weeks of culture. By labeling proliferating cells with a retrovirus-expressing green fluorescent protein, we show that in this system hormone-producing cells are generated de novo. These hormone-producing cells aggregate to form islet-like cell clusters. The cell clusters, when tested in vitro, release insulin in response to glucose and other secretagogues. After transplantation into immunodeficient, nondiabetic mice, the islet-like cell clusters survive and release human insulin. We propose that this system will be useful as an experimental tool for investigating mechanisms for generating new islet cells from the postnatal pancreas, and for designing strategies to generate physiologically competent pancreatic islet cells ex vivo.