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991.
Staging of brain pathology related to sporadic Parkinson's disease 总被引:45,自引:0,他引:45
Braak H Del Tredici K Rüb U de Vos RA Jansen Steur EN Braak E 《Neurobiology of aging》2003,24(2):197-211
Sporadic Parkinson's disease involves multiple neuronal systems and results from changes developing in a few susceptible types of nerve cells. Essential for neuropathological diagnosis are alpha-synuclein-immunopositive Lewy neurites and Lewy bodies. The pathological process targets specific induction sites: lesions initially occur in the dorsal motor nucleus of the glossopharyngeal and vagal nerves and anterior olfactory nucleus. Thereafter, less vulnerable nuclear grays and cortical areas gradually become affected. The disease process in the brain stem pursues an ascending course with little interindividual variation. The pathology in the anterior olfactory nucleus makes fewer incursions into related areas than that developing in the brain stem. Cortical involvement ensues, beginning with the anteromedial temporal mesocortex. From there, the neocortex succumbs, commencing with high order sensory association and prefrontal areas. First order sensory association/premotor areas and primary sensory/motor fields then follow suit. This study traces the course of the pathology in incidental and symptomatic Parkinson cases proposing a staging procedure based upon the readily recognizable topographical extent of the lesions. 相似文献
992.
Petr Ráb Marie Rábová Carla Sofia Pereira Maria João Collares-Pereira Šárka Pelikánová 《Chromosome research》2008,16(6):863-873
Leuciscine cyprinids possess a nearly invariant diploid number (2n = 50) with an extremely uniform karyotype comprising of 8 pairs of metacentric, 13-15 pairs of submetacentric and 2-4 pairs of subtelocentric (st) to acrocentric (a) chromosomes. The largest pair is characteristically an st/a element-the 'leuciscine' cytotaxonomic marker. Previously, the interspecific homology of this chromosome pair could not be assessed owing to the inability to produce euchromatic or serial banding patterns. In the present study, we used laser-microdissection (15-20 copies of the marker chromosome) to construct a whole chromosome probe (WCP) from the marker chromosome of the roach Rutilus rutilus to ascertain the interspecific homology of marker chromosomes by cross-species in-situ hybridization. WCP was hybridized to chromosomes of widely distributed (Abramis brama, Alburnoides bipunctatus, Alburnus alburnus, Aspius aspius, Ballerus ballerus, B. sapa, Blicca bjoerkna, Chondrostoma nasus, Leucaspius delineatus, Leuciscus leuciscus, L. idus, R. rutilus, Scardinius erythrophthalmus, Squalius cephalus, and Vimba vimba) and Iberian endemic species (Achondrostoma oligolepis, Iberochondrostoma almacai, I. lusitanicum, Pseudochondrostoma duriense, S. alburnoides and S. pyrenaicus). Cross-species in-situ hybridization to chromosomes of Phoxinus phoxinus, a representative of leuciscine sister lineage, showed the same pattern as in all of the leuciscins. The probe consistently hybridized to the distal part of the short arm of the marker chromosome, indicating sequence homology. 相似文献
993.
J. Solomina J. Gołębiewska M.R. Kijek A. Kotukhov P.J. Bachul L. Basto K. Gołąb E. Konsur K. Cieply N. Fillman L.-j. Wang C.C. Thomas L.H. Philipson M. Tibudan A. Dębska-Ślizień J. Fung A. Gelrud J.B. Matthews P. Witkowski 《Transplantation proceedings》2017,49(10):2333-2339
Background
Total pancreatectomy (TP) is offered as a last treatment option for pain relief in patients with chronic pancreatitis. Concurrent islets autotransplantation (TP-IAT) may improve glucose control.Methods
We analyzed results in 20 recent patients who underwent TP-IAT at The University of Chicago. The median observation period was 28 months (2–38). Data were collected prospectively then analyzed retrospectively.Results
The number of patients requiring opioids daily for pain control decreased from 16 (80%) prior to surgery to 2 (13%) 1 year after, with only 1 (6.5%) patient experiencing persistent phantom pancreatic pain. Opioid requirements decreased from a median 56.3 (0–240) morphine equivalent dose to 5 (0–130) on day 75 and to 0 (0–30) at 1-year follow up. Five patients (25%) completely stopped insulin support prior to day 75 while maintaining hemoglobin A1c of 5.9% (5–6.3). Eight (53%) patients were insulin free at 1 year with A1c of 6% (5.5–6.8) and a similar rate persisted in next 2 years. For the remaining patients, the more islet function that was preserved, the less insulin they required and A1c was closer to optimal. Quality of Life (QoL) measured by SF36 Physical (PCS) and Mental (MCS) Component Score improved on day 75 (P < .001) and maintained improvement later on. Both PCS and MCS improved regardless of whether patient requires insulin support or not.Conclusions
Improvements of QoL with pain resolution and good glucose control can be achieved after TP-IAT in properly selected patients with CP and intractable pain, regardless of patient insulin support status. 相似文献994.
995.
m. l. lucas n. w. duncan n. f. o'reilly t. j. mcilvenny & y. b. nelson 《Neurogastroenterology and motility》2008,20(5):532-538
Abstract On contact with the mucosa, heat stable (STa) enterotoxin from Escherichia coli reduces fluid absorption in vivo in the perfused jejunum of the anaesthetized rat. The question of whether it also has a vagally mediated remote action on jejunal absorption, when instilled into the ileum, was re-examined, given contradictory findings in the literature. A standard perfused loop preparation was used to measure luminal uptake of fluid in vivo by means of volume recovery. STa in the ileum was found to have no effect on jejunal absorption, regardless of cervical or sub-diaphragmatic vagotomy and also regardless of the nature of the perfusate anion. The batches of toxin were shown in parallel experiments to reduce fluid absorption directly in the jejunum and also in the ileum. Similarly, vagal nerves prior to section had demonstrable in vivo physiological function. There was therefore no evidence for an indirect, vagally mediated ileal effect of STa on proximal fluid absorption. 相似文献
996.
m. a. storr b. yüce † c. n. andrews & k. a. sharkey ‡ 《Neurogastroenterology and motility》2008,20(8):857-868
Abstract Irritable bowel syndrome (IBS) is a spectrum of disorders characterized by abdominal discomfort and pain, associated with altered bowel habits. Though gut motility, secretion and sensation may be altered in patients with IBS, the pathophysiology of this condition remains to be fully understood. The endocannabinoid system is involved in the regulation of numerous gastrointestinal functions including motility, sensation and secretion under both physiological and pathophysiological conditions. Activation of cannabinoid (CB)b>br>1 br> b> and CBb>br>2 br> b> receptors under various circumstances reduces motility, limits secretion and decreases hypersensitivity in the gut. Drugs that alter the levels of endocannabinoids in the gut also reduce motility and attenuate inflammation. In this review, we discuss the role of the endocannabinoid system in gastrointestinal physiology. We go on to consider the involvement of the endocannabinoid system in the context of symptoms associated with IBS and a possible role of this system in the pathophysiology and treatment of IBS. 相似文献
997.
Immunohistochemical localization of substance P NK1 receptor in guinea pig distal colon 总被引:4,自引:0,他引:4
a. m. harrington † j. m. hutson †‡ & b. r. southwell 《Neurogastroenterology and motility》2005,17(5):727-737
BACKGROUND: Neurokinin receptors facilitate tachykinin mediated intestinal motility and secretion. Distribution of Substance P (SP) neurokinin 1 receptor (NK1r) immunoreactivity (IR) has been previously characterized in guinea pig ileum, but not colon. This study localizes NK1rs in guinea pig distal colon. METHODS: Neurons were double labelled for NK1r and either acetylcholine transferase (ChAT), calbindin (calb), neuropeptide Y (NPY), nitric oxide synthase (NOS) or SP. The NK1r endocytosis was induced by 10(-5) mol L(-1) SP, septide, [SarMet] SP or neurokinin A. RESULTS: In guinea pig distal colon, NK1r-IR was present on 70% of submucosal neurons. Sixty-threepercent of the NK1r-IR submucosal neurons were ChAT-IR, 16% calb/SP-IR, 19% NPY-IR and 14% NOS-IR neurons. The NK1r-IR was present on 5% of myenteric neurons. Of these 63% were ChAT-IR, 16% calb-IR neurons and 25% NOS-IR. The NK1rs were also on myenteric plexus interstitial cells of Cajal and on circular muscle. CONCLUSION: In guinea pig distal colon, NK1rs were on 70% of submucosal neurons including all three secretomotor neuron subtypes and sensory neurons, suggesting NK1rs have a major role in neuronal control of mucosal reflexes. The NK1rs were on few myenteric neurons but were dense on muscle cells, suggesting NK1rs affect motility through neuro-muscular rather than neuro-neuronal transmission. 相似文献
998.
Prof. Dr. M. Beer D. Stäb M. Oechsner D. Hahn H. Köstler H. Hebestreit P. Jakob 《Der Radiologe》2009,49(8):732-738
Current diagnostic tools for the assessment of lung function are limited by global measurements or the need for radioactive tracers. Ideally, these tools should allow quantitative, regional distinct analyses without exposure to radiation. The current paper presents oxygen-enhanced functional MRI for assessment of lung ventilation. First applied in humans in 1996, a considerable amount of experience is now available on 1.5T scanners. The generation of quantitative T1-maps shows a high clinical potential. Low-field MR scanners, which are mostly open-designed, are especially interesting for functional lung imaging. The open design has advantages in respect to patient comfort by lower noise production and easy access to the patients and the costs are lower (no need for helium cooling). Lower signal-to-noise ratios can be overcome by changing the relaxation times. New navigator techniques allow further compensations. This article focuses on the presentation of low-field scanners and the application of T1 and T2* maps is described for healthy volunteers and first patients. 相似文献
999.