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51.
Activation of mu opioid receptors (MORs) has a net excitatory effect in the hippocampal formation through inhibition of gamma-amino butyric acid (GABA)-containing interneurons. To determine the precise subcellular targets of MOR agonists, immunoreactivity against MOR1 and GABA was examined in single sections of the hippocampal formation prepared for dual-labeling electron microscopy. In both the CA1 region of hippocampus and the dentate gyrus, MOR-like immunoreactivity (-li) was present in neuronal somata, dendrites, axons, and axon terminals, as well as a very few glial processes. Axon terminals with MOR-li formed symmetric synapses with principal cell dendrites and somata. Many MOR-labeled profiles of all types also contained GABA-li, and the vast majority possessed the ultrastructural characteristics of interneurons. Additionally, in the dentate gyrus a very small proportion of granule cell dendrites contained MOR-li. MOR-li, identified using immunogold-silver particles, was often affiliated with the extrasynaptic regions of neuronal plasma membranes, consistent with responsiveness to diffusing endogenous neuropeptide ligands. Semiquantitative analysis of the distribution of MOR-li revealed significantly more "presynaptic" (axons and terminals) than "postsynaptic" (somata and dendrites) labeled profiles in most laminae. We conclude that in addition to previously described somatodendritic MOR-li, a substantial amount of MOR-li in hippocampal formation is presynaptic. Furthermore, MORs are almost exclusively in GABAergic interneurons. 相似文献
52.
To localize neurotrophin binding sites within the rat dentate gyrus, the distribution of low-affinity p75 neurotrophin receptor (p75NTR) immunoreactivity (IR) was examined by using antiserum raised against the cytoplasmic domain of the receptor. Semiquantitative electron microscopic examination of p75NTR-labeled sections showed that most p75NTR-labeled profiles were axons and axon terminals (72% from a total of 3,975); p75NTR-IR was observed throughout the extent of these structures and was not limited to the plasmalemmal surface. Axons and axon terminals containing p75NTR-IR were distributed in approximately equal proportions across the hilus, infragranular zone, and the inner, middle, and outer molecular layers; significantly fewer p75NTR-labeled profiles were observed in the granule cell layer. Axon terminals containing p75NTR-IR, which made synapses (296 of 552), formed equal proportions of symmetric and asymmetric synapses, primarily with the shafts and spines of dendrites. The remainder of the p75NTR-labeled terminals apposed unlabeled somata and dendrites without forming synapses in the single sections analyzed. In addition, p75NTR-IR was contained within some astrocytes (17.5% of 3,975) and dendritic shafts (3%) and spines (5%). Within dendritic spines, p75NTR-IR was most often associated with the plasmalemmal surface near postsynaptic densities; in dendritic shafts, p75NTR labeling was associated with microfilaments distant from the plasmalemma. Most p75NTR-labeled dendritic profiles were located in the molecular layer, and some originated from granule cells. Moreover, in some granule cell somata (<1% of 3,975), p75NTR-IR was associated with endosomes. The primary localization of p75NTR-IR to presynaptic structures in the dentate gyrus, presumably arising from medial septal/diagonal band neurons, agrees with previous reports. However, p75NTR-IR within some astrocytes, somata, and dendritic structures suggests that this receptor may also be involved in controlling local neurotrophin levels and possibly modulating the viability of local hippocampal cell populations. 相似文献
53.
In the new NHS those who provide services for disabled children need to measure and demonstrate their effectiveness, but there are no easily available outcome measures for use by child development centres and teams. The development of an alternative approach, using a series of statements of good practice, is described. Parents of children with cerebral palsy were asked to participate in semistructured interviews, to ascertain the value and relevance of these quality statements. Parents were most concerned about the standard of news breaking and early follow up, the sharing of information, and the supply and repair of equipment. The findings were used to modify the quality checklist and it is proposed that this should form the basis of a "charter for disabled children and their families''. 相似文献
54.
Survival following emergency surgery for ruptured abdominal aortic aneurysm remains poor and is in stark contrast to that for elective repair. We have carried out a 5-year retrospective observational study to determine the long-term (5-year) survival of patients following emergency surgery for ruptured abdominal aortic aneurysm at a district general hospital in East Anglia. A total of 99 patients presented to the operating theatre for emergency repair of ruptured abdominal aortic aneurysm in this 5-year study period. In-hospital mortality was 70% and was unchanged over the 5 years. Overall long-term survival in those patients discharged from hospital was good. The ICU cost per long-term survivor was calculated to be pound sterling 36750. 相似文献
55.
June Corry Lester J Peters Ieta D' Costa Alvin D Milner Helen Fawns Danny Rischin Sandro Porceddu 《Radiotherapy and oncology》2005,77(2):137-142
BACKGROUND AND PURPOSE: The primary objective of this study was to estimate the rate of tumour response to a cyclical hypofractionated palliative radiotherapy regimen (QUAD SHOT) in previously untreated patients with incurable squamous cell carcinoma of the head and neck. Secondary objectives were to prospectively evaluate toxicity, quality of life (QoL) and survival in these patients. PATIENTS AND METHODS: The QUAD SHOT consisted of 14 Gy in four fractions, given twice a day and at least 6h apart, for 2 consecutive days. This regimen was repeated at 4 weekly intervals for a further two courses if there was no tumour progression. The QoL tool used was an abbreviation of the EORTC QLQ-C30. RESULTS: Thirty eligible patients (29 Stage IV, 20 performance status 2-3) had at least one treatment and 16 patients completed all three cycles. Sixteen patients (53%) had an objective response (2CR, 14PR) and a further seven had stable disease. Median overall survival was 5.7 months, median progression free survival was 3.1 months. The treatment was very well tolerated, with improved QoL in 11 of 25 evaluable patients (44%). CONCLUSION: The QUAD SHOT regimen is an effective palliative treatment with minimal toxicity and a good response rate, which impacts positively on patients' QoL. 相似文献
56.
Chick eyes compensate for defocus imposed by spectacle lenses by making compensatory changes in eye length and choroidal thickness, a laboratory model of emmetropization. To investigate the roles of longitudinal chromatic aberration and of chromatic mechanisms in emmetropization, we examined the participation of different cone classes, and we compared the efficacy of lens compensation under monochromatic illumination with that under white light of the same illuminance to the chick eye.Chicks wore positive or negative 6 D or 8 D lenses on one eye for 3 days, under either blue (460 nm) or red (620 nm) light at 0.67 lux or under white light at 0.67 or 0.2 lux (all measures are corrected for chick photopic sensitivity). The illumination conditions were chosen to differentially stimulate either the short-wavelength and ultraviolet cones or the long-wavelength and double cones. Measurements are expressed as the relative change: the inter-ocular difference in the amount of change over the 3 days of lens wear.We find that under this low illumination the two components of lens compensation were differentially affected by the monochromatic illumination: in blue light lens compensation was mainly due to changes in eye length, whereas in red light lens compensation was mainly due to changes in choroidal thickness. In general, white light produced better lens compensation than monochromatic illumination.
Negative lenses
Under white light negative lenses caused an increase in eye length (60 μm) together with a decrease in choroidal thickness (−51 μm) relative to the fellow eye. Under blue light, although there was an increase in eye length (32 μm), there was no change in choroidal thickness (5 μm). In contrast, under red light there was a decrease in choroidal thickness (−62 μm) but no increase in eye length (8 μm). Relative ocular elongation was the same in white and monochromatic light.Positive lenses
Under white light positive lenses caused a decrease in eye length (−142 μm) together with an increase in choroidal thickness (68 μm) relative to the fellow eye. Under blue light, there was a decrease in eye length (−64 μm), but no change in choroidal thickness (2 μm). In contrast, under red light there was an increase (90 μm) in choroidal thickness but less of a decrease (−36 μm) in eye length. Lens compensation by inhibition of ocular elongation was less effective under monochromatic illumination than under white light (white v red: p = 0.003; white v blue p = .014).The differential effects of red and blue light on the choroidal and ocular length compensatory responses suggest that they are driven by different proportions of the cone-types, implying that, although chromatic contrast is not essential for lens compensation and presumably for emmetropization as well, the retinal substrates exist for utilizing chromatic contrast in these compensatory responses. The generally better lens compensation in white than monochromatic illumination suggests that longitudinal chromatic aberration may be used in lens compensation. 相似文献57.
Judy Wang Patricia Martin-Romano Philippe Cassier Melissa Johnson Eric Haura Laurie Lenox Yue Guo Nibedita Bandyopadhyay Michael Russell Elizabeth Shearin Josh Lauring Laetitia Dahan 《The oncologist》2022,27(7):536
BackgroundPatients with KRAS-mutant cancers have limited treatment options. Here we present a phase I study of JNJ-74699157, an oral, selective, covalent inhibitor of the KRAS G12C isoform, in patients with advanced cancer harboring the KRAS G12C mutation.MethodsEligible patients (aged ≥18 years) who had previously received or were ineligible for standard treatment received JNJ-74699157 once daily on a 21-day cycle. Dose escalation was guided by a modified continual reassessment method.ResultsTen patients (100 mg: 9 and 200 mg: 1) were enrolled. Tumor types included non–small cell lung cancer (n = 5), colorectal cancer (n = 4), and carcinoma of unknown primary site (n = 1). The median age was 65 (range: 36-74) years and median treatment duration was 2.91 (range: 0.5-7.5) months. Dose-limiting toxicities of grades 3–4 increased blood creatinine phosphokinase (CPK) were observed in 100 mg and 200 mg dose levels. The most common adverse event was increased blood CPK (6 patients). No significant clinical benefit was observed; the best response was stable disease in 4 patients (40%).ConclusionBased on dose-limiting skeletal muscle toxicities and the lack of efficacy at the 100 mg dose, further enrollment was stopped. The safety profile of JNJ-74699157 was not considered favorable for further clinical development.ClinicalTrials.gov Identifier NCT04006301相似文献
58.
Gena Schubert Josh Haverland Craig Vander Wyst Jon McGreevy 《Clinical Pediatric Emergency Medicine》2019,20(4):100742
A 3-year-old boy presented to the emergency department with a chief complaint of “lethargy” and was found to have ptosis with eventual respiratory failure and need for emergent intubation. There is a broad differential for a patient with respiratory failure, and careful physical examination and history are imperative to reduce morbidity and prevent mortality. After further evaluation and workup, the diagnosis is ultimately revealed. 相似文献
59.
Michael N. Alonso Josh G. Gregorio Matthew G. Davidson Joseph C. Gonzalez Edgar G. Engleman 《Immunologic research》2014,58(2-3):374-377
Monocytes rapidly infiltrate inflamed tissues and differentiate into CD209+ inflammatory dendritic cells (DCs) that promote robust immunity or, if unregulated, inflammatory disease. Previous studies in experimental animal models indicate that inflammatory DC depletion through systemic elimination of their monocyte precursors with clodronate-loaded liposomes ameliorates the development of psoriasis and other diseases. However, translation of systemic monocyte depletion strategies is difficult due to the importance of monocytes during homeostasis and infection clearance. Here, we describe a strategy that avoids the monocyte intermediates to deplete inflammatory DCs through antibody-loaded toxin. Mice with an abundance of inflammatory DCs as a consequence of lipopolysaccharide exposure were treated with anti-CD209 antibody conjugated to saporin, a potent ribosome inactivator. The results demonstrate depletion of CD209+ DCs. This strategy could prove useful for the targeted reduction of inflammatory DCs in disease. 相似文献
60.