Neuroreport
November 2001
We examined whether the extent of sympathetic sprouting in the dorsal root ganglion was a function of the number of injured nerve fibers. We compared two groups of rats. One group was subjected to unilateral superior and inferior caudal trunk transections at the level between the S1 and S2 spinal nerves (S-I group) and the other group was subjected to unilateral superior caudal trunk transection at the same level (S group).
View Article and Find Full Text PDFChanges in the linear attenuation coefficient of polymer gel dosimeters post-irradiation enable the imaging of dose distributions by x-ray computed tomography (CT). Various compositions of polymer gel dosimeters manufactured from acrylamide (AA), and N,N'-methylene-bis-acrylamide (BIS) comonomers and gelatin or agarose gelling agents were investigated. This work shows that increasing the comonomer concentration increases the CT-dose sensitivity of the polymer gel dosimeter.
View Article and Find Full Text PDFThe nuclear magnetic resonance (NMR) spin-spin relaxation time (T2) is related to the radiation-dependent concentration of polymer formed in polymer gel dosimeters manufactured from monomers in an aqueous gelatin matrix. Changes in T2 with time post-irradiation have been reported in the literature but their nature is not fully understood. We investigated those changes with time after irradiation using FT-Raman spectroscopy and the precise determination of T2 at high magnetic field in a polymer gel dosimeter.
View Article and Find Full Text PDFPhys Med Biol
October 2001
Polymer gel dosimeters of different formulations were manufactured from different monomers of acrylamide, acrylic acid, methacrylic acid, 1-vinyl-2-pyrrolidinone, 2-hydroxyethyl methacrylate and 2-hydroxyethyl acrylate. Gelatin and agarose were used as the gelling agents and N,N'-methylene-bis-acrylamide was used as a co-monomer in each polymer gel dosimeter. The T2 dependence of each dosimeter was analysed using a model of fast exchange of magnetization.
View Article and Find Full Text PDFObjective: The purpose of this study was to compare both the volumes of the lateral ventricles and the cerebral white matter with gestational age at birth of children with periventricular white matter (PVWM) T2-signal hyperintensities on MR images. The spectrum of neuromotor abnormalities associated with these hyperintensities was also determined.
Materials And Methods: We retrospectively reviewed the MR images of 70 patients who were between the ages of 1 and 5 years and whose images showed PVWM T2-signal hyperintensities.
Individuals (n = 39) participated in an outpatient, 16-session individual, manual-guided psychotherapy designed to treat concurrent PTSD and cocaine dependence. Therapy consisted of a combination of imaginal and in-vivo exposure therapy techniques to treat PTSD symptoms and cognitive-behavioral techniques to treat cocaine dependence. Although the dropout rate was high, treatment completers (i.
View Article and Find Full Text PDFAn estimated 30% to 50% of cocaine-dependent individuals meet criteria for lifetime PTSD. This comorbidity has detrimental effects on clinical presentation, and treatment course and outcome. Cocaine dependence is associated with increased rates of exposure to trauma, more severe symptoms, higher rates of treatment attrition and retraumatization, and greater vulnerability to PTSD when compared to other substance use disorders.
View Article and Find Full Text PDFSoc Work Health Care
October 2001
Objectives: The objectives of this study are to assess (a) the level of depressive symptoms among a cohort of HIV infected women and comparable controls and (b) the relationship with covariates including socioeconomic status, substance use, social relations, disease status.
Methods: Participants were enrolled in the Women's Interagency HIV Study (WIHS). Depressive symptoms were measured using the Center for Epidemiological Studies Depression Scale (CESD).
J Bone Joint Surg Br
April 2001
We reviewed all 717 manuscripts published in the 1997 issues of the British and American volumes of the Journal of Bone and Joint Surgery and in Clinical Orthopaedics and Related Research, from which 33 randomised, controlled trials were identified. The results and sample sizes were used to calculate the statistical power of the study to distinguish small (0.2 of standard deviation), medium (0.
View Article and Find Full Text PDFThe effects of ionizing radiation in different compositions of polymer gel dosimeters are investigated using FT-Raman spectroscopy and NMR T2 relaxation times. The dosimeters are manufactured from different concentrations of comonomers (acrylamide and N,N'-methylene-bis-acrylamide) dispersed in different concentrations of an aqueous gelatin matrix. Results are analysed using a model of fast exchange of magnetization between three proton pools.
View Article and Find Full Text PDFIn polymer gel dosimetry using magnetic resonance imaging, the uncertainty in absorbed dose is dependent on the experimental determination of T2. The concept of dose resolution (Dpdelta) of polymer gel dosimeters is developed and applied to the uncertainty in dose related to the uncertainty in T2 from a range of T4 encountered in polymer gel dosimetry. Dpdelta is defined as the minimal separation between two absorbed doses such that they may be distinguished with a given level of confidence, p.
View Article and Find Full Text PDFWe tested the hypothesis that the decrease in spinal levels of SP and CGRP after peripheral nerve injury is related to neuropathic pain. We compared two groups of rats, both of which were subjected to unilateral transection of the inferior and superior caudal trunks between the S1 and S2 spinal nerves. One group exhibited well-developed neuropathic signs after the nerve injury, whereas the other group showed poorly developed signs despite the same nerve injury.
View Article and Find Full Text PDFHypoxic-ischemic injury to the periventricular cerebral white matter [periventricular leukomalacia (PVL)] results in cerebral palsy and is the leading cause of brain injury in premature infants. The principal feature of PVL is a chronic disturbance of myelination and suggests that oligodendrocyte (OL) lineage progression is disrupted by ischemic injury. We determined the OL lineage stages at risk for injury during the developmental window of vulnerability for PVL (23-32 weeks, postconceptional age).
View Article and Find Full Text PDFThe nonstructural protein 3 (NS3) of the hepatitis C virus (HCV) is a bifunctional protein with protease and helicase activities. Nonstructural protein 4A (NS4A) is preceded by NS3 and augments the proteolytic activity of NS3 through protein-protein interaction. The central domain of NS4A has been shown to be sufficient for the enhancement of the NS3 protease activity.
View Article and Find Full Text PDFThe ability of 20 compounds, all but one tobacco constituents, to inhibit the formation of tobacco-specific N-nitrosamines (TSNA) was investigated in buffer and detergent solution and in tobacco midrib and lamina systems. In solution at pH 5.5, ascorbic acid and the phenolic acids caffeic and ferulic acid were the most potent inhibitors of the reaction between nornicotine and nitrite, with nearly complete inhibition at molar ratios test compound/nitrite > 1:1.
View Article and Find Full Text PDFHepatitis C virus (HCV) NS3 protease is responsible for the processing of the viral polyprotein and is considered as a primary target for the development of anti-HCV therapy. We have developed a genetic method in yeast to screen for good substrate sequences of the NS3 protease. A library of fusion proteins was constructed with a transcription factor, GAL4, linked to the intracellular domain of an integral membrane protein, STE2, by a randomized protease substrate sequence.
View Article and Find Full Text PDFThis study examined the relationship between substance use, trauma history, post-traumatic stress disorder (PTSD), and psychiatric comorbidity in a treatment seeking sample of cocaine dependent individuals (N = 91). Structured clinical interviews revealed that 42.9% of the sample met DSM-III-R criteria for lifetime PTSD.
View Article and Find Full Text PDFWe examined whether signals from the neuroma or the dorsal root ganglion of the injured segment are critical for the generation of neuropathic pain. To this aim, we used a rat model of peripheral neuropathy made by transecting the inferior and superior caudal trunks at the level between the S1 and S2 spinal nerves under enflurane anesthesia. These animals displayed tail-withdrawal responses to normally innocuous mechanical stimulation applied to the tail with a von Frey hair (2 g).
View Article and Find Full Text PDFAcetyl-coenzyme A (acetyl-CoA) formed within the plastid is the precursor for the biosynthesis of fatty acids and, through them, a range of important biomolecules. The source of acetyl-CoA in the plastid is not known, but two enzymes are thought to be involved: acetyl-CoA synthetase and plastidic pyruvate dehydrogenase. To determine the importance of these two enzymes in synthesizing acetyl-CoA during lipid accumulation in developing Arabidopsis seeds, we isolated cDNA clones for acetyl-CoA synthetase and for the ptE1alpha- and ptE1beta-subunits of plastidic pyruvate dehydrogenase.
View Article and Find Full Text PDFThis study's purpose was to compare the treatment efficacy and the effects on the patients' quality of life of the pelvic floor muscle (PFM) exercise and the functional electrical stimulation (FES)-biofeedback method. Ninety female incontinence patients were randomly selected and evenly divided into three groups: control, intensive PFM exercise, and FES-biofeedback groups. They were treated for 6 weeks.
View Article and Find Full Text PDFA safe and reproducible mixing procedure for the manufacture of a polymerization-based dosemeter gel evaluated using MRI (PoMRI) is presented. The dose response, obtained by irradiating gel-filled vials with absorbed doses in the interval 0-20 Gy and evaluated with respect to 1/T2, was found to be linear in the interval 0-8 Gy, with a sensitivity of 0.211 s-1Gy-1 (r2 = 0.
View Article and Find Full Text PDFIL-3 deprivation has been reported to induce apoptosis of bone marrow-derived mast cells. In order to evaluate this type of cell death further, we employed trypan blue and propidium iodide stainings, photometric enzyme immunoassay, fluorescence measurement of caspase-3, DNA electrophoresis, flow cytometry and transmission electron microscopy. In this experiment, although several evidences supporting apoptosis were demonstrated some findings were not consistent with typical apoptosis.
View Article and Find Full Text PDFHypoxic-ischemic (H-I) injury to the brain in the perinatal period often leads to significant long-term neurological deficits. In a model of neonatal H-I injury in postnatal day 7 rats, our previous data have shown that cell death with features of apoptosis is prominent between 6 and 24 h after H-I and that neurotrophins, particularly BDNF, can markedly protect against tissue loss. During brain development, caspase-3 is required for normal levels of programmed cell death.
View Article and Find Full Text PDFMR image nonuniformity can vary significantly with the spin-echo pulse sequence repetition time. When MR images with different nonuniformity shapes are used in a T1-calculation the resulting T1-image becomes nonuniform. As shown in this work the uniformity TR-dependence of the spin-echo pulse sequence is a critical property for T1 measurements in general and for ferrous sulfate dosimeter gel (FeGel) applications in particular.
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