Premise Of The Study: Over-browsing of the understory vegetation by white-tailed deer has been a cause of decline in many plant populations. Liliaceae are particularly sensitive, yet individual species differ in their tolerance to deer herbivory. In this paper, we examine whether differences in clonal habit, carbon allocation patterns, and phenology influence the capacity of a species to tolerate and recover from repeated herbivory.
View Article and Find Full Text PDFChronic pain is associated with reduced brain gray matter and impaired cognitive ability. In this longitudinal study, we assessed whether neuroanatomical and functional abnormalities were reversible and dependent on treatment outcomes. We acquired MRI scans from chronic low back pain (CLBP) patients before (n = 18) and 6 months after (spine surgery or facet joint injections; n = 14) treatment.
View Article and Find Full Text PDFCalcification is a pathological process that may lead to impairment of nutrient supply and disc metabolism in degenerative and scoliotic intervertebral discs (IVDs). The purpose of this study was to assess the calcification potential of IVDs in degenerative disc disease (DDD) and adolescent idiopathic scoliosis (AIS). For this purpose, 34 IVDs from 16 adult patients with DDD and 25 IVDs from 9 adolescent patients with AIS were obtained at surgery.
View Article and Find Full Text PDFIn adolescent idiopathic scoliosis (AIS) there has been a shift towards increasing the number of implants and pedicle screws, which has not been proven to improve cosmetic correction. To evaluate if increasing cost of instrumentation correlates with cosmetic correction using clinical photographs. 58 Lenke 1A and B cases from a multicenter AIS database with at least 3 months follow-up of clinical photographs were used for analysis.
View Article and Find Full Text PDFClin Orthop Relat Res
May 2011
Background: The challenge when managing early-onset scoliosis (EOS) is to prevent curve progression while maintaining spinal growth. Current surgical treatments (growing rods, VEPTR) require repetitive interventions to lengthen the implants.
Questions/purposes: We asked whether a modern Luqué trolley construct could achieve and maintain scoliosis correction in EOS during spinal growth without the need for repetitive surgeries, thus decreasing the morbidity of the surgical treatment.
Study Design: Human intervertebral discs were used to develop an intact whole disc organ culture system with long-term cell viability.
Objective: To develop and validate a long-term organ culture system for intact human intervertebral discs, in which the potential for biologic repair of disc degeneration can be studied.
Summary Of Background Data: Intervertebral disc degeneration is a common cause of back pain, which can be costly to the health care system and have a negative impact on the quality of life of the patient.
Intratumoral biosynthesis of hormone steroids is thought to play a role in the pathogenesis and development of human breast cancer. There is evidence that glucocorticoids may inhibit the development and progression of breast cancer. 11β-hydroxysteroid dehydrogenase (11β-HSD) type 1 is the enzyme which converts inactive cortisone to active cortisol.
View Article and Find Full Text PDFObjective: The "risk compensation" hypothesis suggests that individuals offset perceived gains in safety by increasing their risk-taking behavior to maintain a stable or "homeostatic" level of risk. If this is true for motorcyclists, then helmet use, which reduces the risk of brain injury and death, may lead helmet users to take more risks when they ride. Thus, increased risk-taking by helmet users should show up as overrepresentation in crashes, and accident reconstruction should reveal risky behaviors in the seconds just before the crash.
View Article and Find Full Text PDFBackground: Chemotherapy is increasingly used in colorectal liver metastases (CRLMs) even when they are initially resectable. The aim of our study was to address the still pending question of whether perioperative chemotherapy is really beneficial in patients developing solitary metastases at a distance from surgery of the primary.
Methods: We analyzed a multicentric cohort of 1471 patients resected for solitary, metachronous, primarily resectable CRLMs without extrahepatic disease in the LiverMetSurvey International Registry over a 15-year period.
Although effluent treatment systems within pulp and paper mills remove many toxicants and improve wastewater quality, there is a need to understand and quantify the effectiveness of the treatment process. At a combined news and kraft pulp and paper mill in northwestern Ontario, Canada, fathead minnow (FHM) reproduction and physiology were examined before, during, and after a short-term (6-d) exposure to 10% (v/v) untreated kraft mill effluent (UTK), 25% (v/v) secondary treated kraft mill effluent (TK), and 100% (v/v) combined mill outfall (CMO). Although UTK exposure significantly decreased egg production, neither TK nor CMO caused any reproductive changes.
View Article and Find Full Text PDFEvid Based Spine Care J
August 2010
Study Type: Basic science Objective: Low back pain is one of the most common health problems1 and is strongly associated with intervertebral disc degeneration, (IVD). Current treatments remove the symptoms without reversing or even retarding the underlying problem. Development of new therapy for the regeneration of the degenerative IVD is complicated by the lack of a validated long-term organ culture model in which therapeutic candidates can be studied.
View Article and Find Full Text PDFThe hepatitis C virus internal ribosome entry site (IRES) element contains a three-way junction that is important in the overall RNA conformation, and for its role in the internal initiation of translation. The junction also illustrates some important conformational principles in the folding of three-way helical junctions. It is formally a 3HS(4) junction, with the possibility of two alternative stacking conformers.
View Article and Find Full Text PDFA major drawback of current cartilage and intervertebral disc tissue engineering is that human mesenchymal stem cells (MSCs) from osteoarthritic (OA) patients express type X collagen (COL10), a marker of late-stage chondrocyte hypertrophy (associated with endochondral ossification). Parathyroid hormone (PTH) regulates endochondral ossification by inhibiting chondrocyte differentiation toward hypertrophy. In this study, we investigated the effect of PTH on expression of COL10 in MSCs from OA patients and analyzed the potential mechanisms related to its effect.
View Article and Find Full Text PDFWell-differentiated neuroendocrine tumours (nets-previously called "carcinoid tumours") are relatively rare tumours originating from the diffuse neuroendocrine system; they are found most often in the bronchial or gastrointestinal systems. In Canada, gastroenterohepatic NETS represent less than 0.25% of oncology cases.
View Article and Find Full Text PDFThe kink-turn (k-turn) is a common structural motif in RNA that introduces a tight kink into the helical axis. k-turns play an important architectural role in RNA structures and serve as binding sites for a number of proteins. We have created a database of known and postulated k-turn sequences and three-dimensional (3D) structures, available via the internet.
View Article and Find Full Text PDFObjective: Our objective was to compare the use of misoprostol to that of laminaria tents for dilatation of the cervix before a surgical elective abortion (EAB) during the first trimester, with regard to the pain caused (1) during insertion, for both methods, (2) immediately before the EAB, and (3) one hour after the procedure.
Methods: One hundred two women were recruited at Clinique de planification des naissances du Centre hospitalier universitaire de Québec, CHUL pavilion, between March 1, 2006 and March 1, 2007, for a tracking study. Fifty-three women were given 400 microg of misoprostol intravaginally, three to four hours before the EAB, and a laminaria tent was inserted in 49 women, 16 to 24 hours before the EAB.
Study Design: A cell-based assay was developed to identify asymptomatic children at risk of developing idiopathic scoliosis (IS) and to stratify IS patients at an earlier stage in order to better predict their clinical outcome. Clinical validation of this assay was performed by testing IS patients at different stages, healthy control subjects, and asymptomatic offspring, born from at least one scoliotic parent, who are considered at risk of developing this disorder.
Objective: Our goal was to develop and validate a clinical test for IS using cellular dielectric spectroscopy (CDS) and peripheral blood mononuclear cells (PBMCs).
Stable isotope composition (delta(13)C and delta(15)N) of moose (Alces alces) and caribou (Rangifer tarandus) hair from the boreal forest of Jacques-Cartier Park and Cote-Nord (Quebec) and arctic tundra of Queen Maud Gulf and Southampton Island (Nunavut) was investigated as an indicator of dietary preferences and habitat use. Values of delta(13)C(hair) and delta(15)N(hair) in moose were consistently lower compared to those of caribou. This is consistent with the depletion in (13)C and (15)N in the plants preferred by moose, essentially browse (shrub and tree leaves), compared to caribou forage, which included significant amounts of graminoids, lichen and fungi.
View Article and Find Full Text PDFJ Int Neuropsychol Soc
March 2010
We examined the capacity of patients with multiple sclerosis (MS) to attribute mental states to others and to identify cognitive abilities that subserve theory of mind (ToM). In this article, we report findings on 41 out-patients with diagnosed MS who underwent detailed neuropsychological and social-cognitive assessment. They were subdivided into a cognitively intact (n=15) and cognitively impaired (n=26) group according to their neuropsychological test results.
View Article and Find Full Text PDFThe sex steroids, estrogens, progesterone, and androgens, all play a role in mammary development and function. To precisely identify the sites of action of these steroids, we studied the localization of the estrogen receptor alpha (ERalpha) and ERbeta, the progesterone receptor A (PRA) and PRB, and androgen receptors (AR) in the normal human mammary gland. Immunocytochemical localization of ERalpha, ERbeta, PRA, PRB, and AR was performed with reduction mammoplasty specimens from premenopausal women.
View Article and Find Full Text PDFSpine (Phila Pa 1976)
November 2009
Study Design: A retrospective analysis of prospectively collected data on a cohort of 19 myelomeningocele patients undergoing spino-pelvic deformity surgery.
Objective: To examine if greater curve correction with third generation spinal implants correlate with improved pressure distribution and resolution, or prevention of skin ulcerations in myelomeningocele patients.
Summary Of Background Data: Children born with myelomeningocele have often complex spino-pelvic deformities leading to skin ulcerations.
The complete VS ribozyme comprises seven helical segments, connected by three three-way RNA junctions. In the presence of Mg(2+) ions, cleavage occurs within the internal loop of helix I. This requires the participation of a guanine (G638) within the helix I loop, and a remote adenine (A756) within an internal loop of helix VI.
View Article and Find Full Text PDFSuperiority of pedicle screws over hybrid/hook instrumentation or vice versa in the treatment of Lenke Type 1 and 2 adolescent idiopathic scoliosis (AIS) remains unresolved for moderate curves. Our objective was therefore to compare the assessment of pedicle screw and hybrid/hooks instrumentation with special attention to cosmesis and uninstrumented spine using novel assessment methods. We carried out a retrospective study of radiographs and clinical photos of 40 cases of thoracic AIS between 40 degrees and 70 degrees of Cobb angle Lenke Type 1 and 2, treated with either pedicle screws or hybrid/hooks.
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