Adeno-associated viral vector 9 (AAV9) has recently been shown to penetrate the blood-brain barrier via intravascular administration, making it a good candidate for diffuse gene delivery. However, ...the potential side effects of systemic delivery are unknown. Intrathecal viral vector administration may be more invasive than intravenous injections, but it requires far less vector and it can be performed on an outpatient basis, making it an ideal route of delivery for clinical translation. A total of 12 domestic farm pigs (<20 kg) underwent a single-level lumbar laminectomy with intrathecal catheter placement for AAV9 delivery. Animals were perfused and the tissue was harvested 30 days after treatment. Gene expression was assessed by anti-green fluorescent protein immunohistochemistry. Although a single lumbar injection resulted in gene expression limited to the lumbar segment of the spinal cord, three consecutive boluses via a temporary catheter resulted in diffuse transduction of motor neurons (MNs) throughout the cervical, thoracic and lumbar spinal cords. We now present the first successful robust transduction of MNs in the spinal cord of a large animal via intrathecal gene delivery using a self-complementary AAV9. These promising results can be translated to many MN diseases requiring diffuse gene delivery.
In response to the plastic waste crisis, teabag producers have substituted the petrochemical-plastic content of their products with bio-based, biodegradable polymers such as polylactic acid (PLA). ...Despite widespread use, the degradation rate of PLA/PLA-blended materials in natural soil and their effects on soil biota are poorly understood. This study examined the percentage mass deterioration of teabags with differing cellulose:PLA compositions following burial (−10 cm depth) in an arable field margin for 7-months, using a suite of analytical techniques, such as size exclusion chromatography, 1H nuclear magnetic resonance, dynamic scanning calorimetry, and scanning electron microscopy. The effect of 28-d exposure to teabag discs at environmentally relevant concentrations (0.02 %, 0.04 % and 0.07 % w/w) on the survival, growth and reproduction (OECD TG 222 protocol) of the key soil detritivore Eisenia fetida was assessed in laboratory trials. After 7-month burial, Tbag-A (2.4:1 blend) and Tbag-B (3.5:1 cellulose:PLA blend) lost 66 ± 5 % and 78 ± 4 % of their total mass, primarily attributed to degradation of cellulose as identified by FTIR spectroscopy and a reduction in the cellulose:PLA mass ratio, while Tbag-C (PLA) remained unchanged. There were clear treatment and dose-specific effects on the growth and reproductive output of E. fetida. At 0.07 % w/w of Tbag-A adult mortality marginally increased (15 %) and both the quantity of egg cocoons and the average mass of juveniles also increased, while at concentrations ≥0.04 % w/w of Tbag-C, the quantity of cocoons was suppressed. Adverse effects are comparable to those reported for non-biodegradable petrochemical-based plastic, demonstrating that bio-based PLA does not offer a more ‘environmentally friendly’ alternative. Our study emphasises the necessity to better understand the environmental fate and ecotoxicity of PLA/PLA-blends to ensure interventions developed through the UN Plastic Pollution Treaty to use alternatives and substitutes to conventional plastics do not result in unintended negative consequences.
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•Soil deterioration and ecotoxicity of cellulose:PLA teabags were studied.•The mass ratio of teabag cellulose:PLA decreased following 7-months field degradation.•Mass loss was attributed to degradation of cellulose (rather than PLA) fibres.•Treatment and dose-specific effects of teabags on E. fetida reproductive output•Bio-based ‘plastic substitutes’ require evaluation to avoid negative consequences.
An emerging theme in the study of the pathophysiology of chronic and persistent pain is the role of pro-oxidant substances. Reactive oxygen species (ROS) have been implicated in contributing to ...and/or maintaining conditions of chronic pain. Recent pre-clinical reports suggest that antioxidants are effective analgesics in neuropathic and inflammatory pain models. The present study extends this work by examining the effect of three antioxidants on tissue injury-induced nociception. C57BL6 mice (20–25
g) were pretreated with either phenyl-
N-
tert-butylnitrone (PBN; 50
mg/kg, i.p.), 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxy (TEMPOL; 200 or 50
mg/kg, i.p.),
N-acetyl-
l-cysteine (NAC; 200 or 100
mg/kg, i.p.), or vehicle (0.5
ml/100
g), 5
min before intraplantar formalin (10%, 20
μl) injection. Nociceptive responding, indicated by licking or biting the affected hindlimb, was quantified for 30
min after formalin injection. Each drug was effective in attenuating two or more phases (acute, quiescent, and tonic) of the formalin response. To assess putative site of action, intrathecal TEMPOL (380
nmol/5
μl, i.t.) was given 5
min before intraplantar formalin. Intrathecal TEMPOL produced a 83% reduction in nociceptive responding in the tonic phase, but no significant attenuation of the acute phase response. To confirm that the antioxidant property of intrathecal TEMPOL was responsible for its analgesic effect on the formalin-induced pain response, intrathecal TEMPOL was coadministered with the free radical donor
tert-butylhydroperoxide (
tert-BuOOH).
Tert-BuOOH coadminstration reversed the TEMPOL-induced analgesia in the tonic intraplantar formalin response reduction. The data suggest that pro-oxidant species may be important mediators of tissue injury-induced algesia in rodents, and that a spinal site of action is implicated in the tonic response.
Plasma glutathione peroxidase (GPx-3) is a selenocysteine-containing protein with antioxidant properties. GPx-3 deficiency has been associated with cardiovascular disease and stroke. The regulation ...of GPx-3 expression remains largely uncharacterized, however, and we studied its transcriptional and translational determinants in a cultured cell system. In transient transfections of a renal cell line (Caki-2), the published sequence cloned upstream of a luciferase reporter gene produced minimal activity (relative luminescence (RL) = 0.6 ± 0.4). Rapid amplification of cDNA ends was used to identify a novel transcription start site that is located 233 bp downstream (3′) of the published site and that produced a >25-fold increase in transcriptional activity (RL = 16.8 ± 1.9; p < 0.0001). Analysis of the novel GPx-3 promoter identified Sp-1- and hypoxia-inducible factor-1-binding sites, as well as the redox-sensitive metal response element and antioxidant response element. Hypoxia was identified as a strong transcriptional regulator of GPx-3 expression, in part through the presence of the hypoxia-inducible factor-1-binding site, leading to an almost 3-fold increase in expression levels after 24 h compared with normoxic conditions (normalized RL = 3.5 ± 0.3 versus 1.2 ± 0.1; p < 0.001). We also investigated the role of the translational cofactors tRNASec, SECIS-binding protein-2, and SelD (selenophosphate synthetase D) in GPx-3 protein expression. tRNASec and SelD significantly enhanced GPx-3 expression, whereas SECIS-binding protein-2 showed a trend toward increased expression. These results demonstrate the presence of a novel functional transcription start site for the human GPx-3 gene with a promoter regulated by hypoxia, and identify unique translational determinants of GPx-3 expression.
The interferon (IFN)-induced, double-stranded (ds)RNA-activated serine-threonine protein kinase, PKR, is a key mediator of the antiviral activities of IFNs. In addition, PKR activity is also involved ...in regulation of cell proliferation, apoptosis, and signal transduction. In virally infected cells, dsRNA has been shown to bind and activate PKR kinase function. Implication of PKR activity in normal cellular processes has invoked activators other than dsRNA because RNAs with perfectly duplexed regions of sufficient length that are able to activate PKR are absent in cellular RNAs. We have recently reported cloning of PACT, a novel protein activator of PKR. PACT heterodimerizes with PKR and activates it by direct protein-protein interaction. Overexpression of PACT in mammalian cells leads to phosphorylation of the α subunit of the eukaryotic initiation factor 2 (eIF2α), the cellular substrate for PKR, and leads to inhibition of protein synthesis. Here, we present evidence that endogenous PACT acts as a protein activator of PKR in response to diverse stress signals such as serum starvation, and peroxide or arsenite treatment. Following exposure of cells to these stress agents, PACT is phosphorylated and associates with PKR with increased affinity. PACT-mediated activation of PKR leads to enhanced eIF2α phosphorylation followed by apoptosis. Based on the results presented here, we propose that PACT is a novel stress-modulated physiological activator of PKR.
We present a serious postoperative complication related to the use of femoral nerve block in 4 patients, each of whom fell and sustained further injury. Preoperatively, all patients underwent a ...3-in-1 femoral nerve block with 30 to 35 ml of 0.25% levobupivacaine with 1:200 000 epinephrine, with guidance by a nerve stimulator. After the falls, neurological examination of the operated legs revealed reduced 2-point discrimination, pain, and/or light touch sensation. All patients underwent further operation for the fall injury and had delayed full weight bearing. We recommend that, after having a femoral nerve block, patients should undergo enhanced postoperative evaluation of blockade and proprioceptive function to ensure safe neurological function before mobilisation.
Although men and women bicycle at relatively equal rates in industrialized countries such as the Netherlands, Germany, and Denmark, research has consistently found that in the United States men's ...total bicycle trips surpass women's by a ratio of at least 2 to 1. Current evidence, though limited, suggests that women are affected to greater or lesser degrees than men by certain factors. The purpose of this study is to provide insight on gender differences with the factors that influence the decision to use a bicycle, with the intent of supporting policy development aimed at increasing bicycle ridership, particularly among women. Bicycle use in six small cities in the western United States is examined to determine how gender interacts with individual factors and social and physical environments to influence bicycle behavior. Analysis of data from an online survey using a binary logistic regression approach shows strong interaction of gender with individual factors such as safety perception and household responsibilities and, to a lesser degree, with social and environmental factors to influence bicycle behavior.
The relationship between travel behavior and the local built environment remains far from entirely resolved, despite several research efforts in the area. The significance and explanatory power of a ...variety of urban form measures on nonwork activity travel mode choice have been investigated. The travel data used for analysis are from the 1995 Portland Metropolitan Activity Survey conducted by Portland Metro. The database on the local built environment was developed by Song in 2002 and includes a more extensive set of variables than previous studies that have examined the relationship between travel behavior and the local built environment by using the Portland data. The results of the multinomial logit mode choice model indicate that mixed uses promote walking behavior for nonwork activities.
Enhancing community environments to support walking and bicycling serves as a promising approach to increase population levels of physical activity. However, few studies have simultaneously assessed ...perceptions and objectively measured environmental factors and their relative association with transportation or recreational physical activity.
For this cross-sectional study, high- and low-income study areas were selected among census tracts in St. Louis MO (“low-walkable” city) and Savannah GA (“high-walkable” city). Between February and June 2002, a telephone survey of 1068 adults provided measures of the perceived environment and physical activity behavior. In this timeframe, objective measures were collected through environmental audits of all street segments (
n =1158). These measures were summarized using 400-m buffers surrounding each respondent. Neighborhood characteristics included the land use environment, transportation environment, recreational facilities, aesthetics, and social environment. Associations were examined between neighborhood features and transportation- and recreation-based activity.
After adjusting for age, gender, and education, transportation activity was negatively associated with objective measures of sidewalk levelness and perceived and objective neighborhood aesthetics. It was positively associated with perceived and objectively measured number of destinations and public transit, perceived access to bike lanes, and objective counts of active people in the neighborhood. Recreational activity was positively associated with perceived access to recreational facilities and objective measures of attractive features.
These findings indicate that physical activities for transportation or recreational are associated with different perceived and objective environmental characteristics. Modifications to these features may change the physical activity behavior of residents exposed to them.
The Transition Region and Coronal Explorer (TRACE) satellite, launched 2 April 1998, is a NASA Small Explorer (SMEX) that images the solar photosphere, transition region and corona with unprecedented ...spatial resolution and temporal continuity. To provide continuous coverage of solar phenomena, TRACE is located in a sun-synchronous polar orbit. The 6700 Mbytes of data which are collected daily are made available for unrestricted use within a few days of observation. The instrument features a 30-cm Cassegrain telescope with a field of view of 8.5 x .5 arc min and a spatial resolution of 1 arc sec (0.5 arc sec pixels). TRACE contains multilayer optics and a lumogen-coated CCD detector to record three EUV wavelengths and several UV wavelengths. It observes plasmas at selected temperatures from 6000 K to 10 MK with a typical temporal resolution of less than 1 min.
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