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11.
Israel Liberzon Stephan F Taylor K Luan Phan Jennifer C Britton Lorraine M Fig Joshua A Bueller Robert A Koeppe Jon-Kar Zubieta 《Neuropsychopharmacology》2007,61(9):1030-1038
BACKGROUND: Functional neuroimaging studies have detected abnormal limbic and paralimbic activation to emotional probes in posttraumatic stress disorder (PTSD), but few studies have examined neurochemical mechanisms that underlie functional alterations in regional cerebral blood flow. The mu-opioid neurotransmitter system, implicated in responses to stress and suppression of pain, is distributed in and is thought to regulate the function of brain regions that are implicated in affective processing. METHODS: Here we examined the micro-opioid system with positron emission tomography and the micro-opioid receptor-selective radiotracer [11C] carfentanil in 16 male patients with PTSD and two non-PTSD male control groups, with (n = 14) and without combat exposure (n = 15). Differences in micro-opioid receptor binding potential (BP2) were detected within discrete limbic and paralimbic regions. RESULTS: Relative to healthy controls, both trauma-exposed groups had lower micro-opioid receptor BP2 in extended amygdala, nucleus accumbens, and dorsal frontal and insular cortex but had higher BP2 in the orbitofrontal cortex. PTSD patients exhibited reduced BP2 in anterior cingulate cortex compared with both control groups. Micro-opioid receptor BP2 in combat-exposed subjects without PTSD was lower in the amygdala but higher in the orbitofrontal cortex compared with both PTSD patients and healthy controls. CONCLUSIONS: These findings differentiate the general response of the micro-opioid system to trauma from more specific changes associated with PTSD. 相似文献
12.
Wang C Auerbach JD Witschey WR Balderston RA Reddy R Borthakur A 《Seminars in spine surgery》2007,19(2):65-71
The intervertebral disc is characterized by a tension-resisting annulus fibrosus, and a compression-resisting nucleus pulposus composed largely of proteoglycan. Both the annulus and the nucleus function in concert to provide the disc with mechanical stability. Early disc degeneration begins in the nucleus with proteoglycan depletion. Quantitative MRI techniques have been developed to non-invasively quantify the earliest degenerative changes that occur within the disc. Our ability to identify and quantify these early biochemical changes will provide a better understanding of the pathophysiology of disc degeneration and facilitate the study of interventions that aim to halt or reverse the degenerative process. 相似文献
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Harold T. Kyriazi George E. Carvell Joshua C. Brumberg Daniel J. Simons 《Brain research》1996,712(2):325
Extracellular single-unit recordings were made in somatosensory cortical barrels of fentanyl-sedated rats. Whiskers were deflected singly or in paired combinations. lontophoretically-applied (−)-baclofen disproportionately reduced weak responses, and phaclofen disproportionately increased them, resulting in more tightly focused or more broadly focused receptive fields, respectively. Both drugs had only minor effects on surround inhibition. In light of previous findings, we conclude that GABAA and GABAB mechanisms both act to enhance spatial contrast, but that the former plays a much greater role in enhancing temporal resolution. 相似文献
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Dave F Clarke James W Wheless Monica M Chacon Joshua Breier Mary-Kay Koenig Mark McManis Edward Castillo James E Baumgartner 《Seizure》2007,16(6):545-553
Corpus callosotomy has a long history as a palliative treatment for intractable epilepsy. Identification of a single epileptogenic zone is critical to performing successful resective surgery. We describe three patients in which corpus callosotomy allowed recognition of unapparent seizure foci, leading to subsequent successful resection. We retrospectively reviewed our epilepsy surgery database from 2003 to 2005 for children who had a prior callosotomy and were candidates for focal resection. All underwent magnetic resonance imaging and scalp video electroencephalograph monitoring, and two had magnetoencephalography, electrocorticography and/or intracranial video electroencephalograph monitoring. The children were 8 and 9 years old, and seizure onset varied from early infancy to early childhood. One child had a history of head trauma preceding seizure onset, one had a large intracerebral infarct and dysplastic cortex in the contralateral frontal lobe, and the other had an anterior temporal lobe resection without improvement in seizure frequency. After medical management failed, callosotomy was performed with the expectation of decreasing the seizure types affecting both hemispheres. Following transection of the callosal fibers, a single focus was recognized and resected, with resultant dramatic improvement in seizure control. In medically refractory epilepsy, where rapid secondary bisynchrony is suspected but the electroencephalograph is non-localizing, callosotomy should be considered as a means of treating generalized seizure types, but may also assist in identifying potentially operable seizure foci. Study limitations include its retrospective nature and cohort size. The findings, however, suggest the need for prospective, systematic, well-controlled studies of the use of corpus callostomy in this intractable patient population. 相似文献
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Doug Joshua Max Wolf Jane Matthews Lee Tan William Sheridan Glenn Pilkingtonh Fiona Page 《Leukemia & lymphoma》1994,14(3):303-309
The Australian Leukaemia Study Group myeloma study (MM1) aimed to determine the prognostic significance of clinical and immunophenotypic markers in patients with multiple myeloma. All patients were treated with standard dose melphalan and prednisone. Seventy-four patients were entered and the median survival was 27 months. Serum beta 2-microglobulin (βM) and albumin levels were the only significant clinical factors influencing survival (p = 0.007 and p = 0.008, respectively). Patients with raised levels of CD38+ lymphocytes at presentation had a significantly shorter survival than patients with normal levels (p = 0.01, logrank test, median 19 months vs 33 months). CD38 antigen expression was independent of β2M but patients with raised levels of CD38 had significantly lower levels of albumin than patients with normal levels (p = 0.001) which may explain their poorer survival. Salmon and Durie stage was not associated with antigen expression. No other B-cell antigens (CD10, CD19, CD20, CD21, CD22, CD23, FMC1 or FMC7) or plasma cell antigens tested (PCA-1) were found to be associated with prognosis. Patients who achieved plateau phase had a better prognosis than those who did not (p = 0.04 in a landmark analysis). Patients who achieved plateau phase following an objective response appeared to have a better prognosis than those who were in plateau phase at presentation (p = 0.09 in a landmark analysis). Light chain isotype suppression (LCIS) was not associated with a significant survival advantage and did not correlate with any known prognostic indicator. We conclude that phenotypic analysis of peripheral blood lymphocytes for CD38 antigen at diagnosis may be useful as a prognostic indicator in patients with myeloma. 相似文献
19.
Neonatal septicaemia (NNS) is a major cause of neonatal morbidity and mortality. Neonatal septicaemia was studied to determine the incidence, common bacterial aetiology and antibiotic susceptibility in Qatif Central Hospital, Saudi Arabia. Of 1,797 babies admitted into the unit over a 3 year period, 144 (8.0%) had documented neonatal septicaemia consisting of 94 (65%) late onset and 50 (35%) early onset septicaemia. The incidence was 8.2/1000 of the total live births in the hospital.
Gram negative bacteria were encountered in 66.2%, gram positive bacteria in 29.2% and Candida albicans in 4.4% of the case. Klebsiella spp., E. coli, and Pseudomonas accounted for 81.8 % of the gram negative while Staphylococcus epidermidis, Staphylococcus aureus and group B Beta haemolytic Streptococcus accounted for 73.9% of the gram positive bacteria.
Most of Gram negative bacteria had a high sensitivity to Aminoglycosides and third generation Cephalosporins. Coagulase negative staphylococci were frequently resistant to most antibiotics but always sensitive to Vancomycin. The overall mortality rate was 18.7%. 相似文献
Gram negative bacteria were encountered in 66.2%, gram positive bacteria in 29.2% and Candida albicans in 4.4% of the case. Klebsiella spp., E. coli, and Pseudomonas accounted for 81.8 % of the gram negative while Staphylococcus epidermidis, Staphylococcus aureus and group B Beta haemolytic Streptococcus accounted for 73.9% of the gram positive bacteria.
Most of Gram negative bacteria had a high sensitivity to Aminoglycosides and third generation Cephalosporins. Coagulase negative staphylococci were frequently resistant to most antibiotics but always sensitive to Vancomycin. The overall mortality rate was 18.7%. 相似文献
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