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Cutaneous wound pain causes physical and psychological stress for patients with wounds. Previous studies reported that stress induces hyperalgesia and deteriorates wound healing. However, the effect of the stress response such as in hypothalamic‐pituitary‐adrenal (HPA) axis on local wound area is unclear. We aimed to investigate the effects of a stress response on the mechanical withdrawal threshold in the local wound area and describe the identification of a wound pain exacerbation. We topically injected adrenocorticotropic hormone (ACTH) into the granulation tissue of full‐thickness cutaneous wound model rats on the fifth day postwounding and measured the mechanical withdrawal thresholds, cytochrome P450 2Bs levels and concentration of 5,6‐epoxyeicosatrienoic acid in wound exudate. We found that ACTH induced mechanical hypersensitivity at 4 and 6 hours after injection (P = .004 and .021, respectively), and increased gene expression of cytochrome P450 2B12 expression (P = .046). Concentration of 5,6‐EET in the wound exudate was moderately correlated with the mechanical withdrawal threshold (r = ?.630). Finally, the mechanical withdrawal threshold in the 5,6‐EET group was significantly lower than that in the control group at 2 hours after the injection (P = .015). We propose that 5,6‐EET is one of the most promising contributors to the wound pain exacerbation. These findings could guide clinical wound and pain management.  相似文献   
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In Cryptococcus neoformans the DNA content of cells having tiny buds varied rather widely, depending on growth phases and strains used. Typically, buds of C. neoformans emerged soon after initiation of DNA synthesis in the early exponential phase. However, bud emergence was delayed to G2 during transition to the stationary phase, and in the early stationary phase budding scarcely occurred, although roughly half of the cells completed DNA synthesis. The timing of budding in C. neoformans was shifted to later cell cycle points with progression of the growth phase of the culture. Similarly, a deficit in oxygen was demonstrated to delay the timing of budding, prolong the G2 phase and cause accumulation of cells after DNA synthesis, but before commitment to budding. The C. neoformans homologue of the main cell cycle control gene CDC28/Cdc2 was isolated using degenerate RT-PCR. The full-length coding region was then amplified using primers to target the regions around the start and stop codons. The gene was called CnCdk1 and was found to have high homologies to S. cerevisiae CDC28 and S. pombe cdc2. To determine its function, its ability to rescue S. cerevisiae cdc28-temperature sensitive mutants was tested. S. cerevisiae cdc28-4 and cdc28-1N strains transformed with the pYES2-CnCdk1 construct exhibited growth at the restrictive temperature. Results of the sequence analysis and the ability of CnCdk1 to complement the S. cerevisiae cdc28-ts mutations support its assumed role as the CDC28/cdc2 homologue in C. neoformans.  相似文献   
4.
The biochemical activities of 8 lysosomal acid hydrolases in leukemic cells from 48 patients were examined. Characteristic alterations were found in α-mannosidase, β-galactosidase and N-acetyl-β-glucosaminidase activities of leukemic cells. The level of α-mannosidase activity was much higher in myelo(mono)genous leukemias (AML, AMoL, AMMoL, CML and CMMoL) than in lymphogenous ones (ALL, T-cell leukemia, hairy cell leukemia and CLL) without exception. The β-galactosidase activity also differed as a result of α-mannosidase, except in T-cell leukemia. In T-cell leukemia it was within the range of normal lymphocytes, but in the other lymphogenous leukemias it was significantly below normal. N-acetyl-β-glucosaminidase activity in myelo(mono)genous leukemic cells was above the range of normal granulocytes. The changes in these enzyme levels were consistent. The lymphocytic or myelocytic nature of three cases of acute undifferentiated leukemia could be determined by enzyme studies. In two cases it was lymphocytic and in one it was myelocytic. The enzymatic abnormalities were also found in morphologically mature neutrophils from patients with not only chronic types (CML, CMMoL) but also acute types (AMoL, AMMoL) of leukemias, and were similar to those of their respective leukemic cells. Analysis of lysosomal enzymes (at least three of those mentioned above), can elucidate one of the biochemical properties of leukemic cells and may be valuable in the differentiation of leukemias.  相似文献   
5.
Suda  J; Eguchi  M; Akiyama  Y; Iwama  Y; Furukawa  T; Sato  Y; Miura  Y; Suda  T; Saito  M 《Blood》1987,69(2):508-512
A male neonate with Down's syndrome and congenital myeloproliferative disorder was studied. His blood picture showed the unique coexistence of leukocytosis with matured cells and a large number of blast cells. The in vitro proliferation and differentiation of blast cells into various lineages in the presence of phytohemagglutinin-stimulated leukocyte conditioned medium (PHA-LCM) was examined by using a liquid culture and a methylcellulose culture system. The differentiation of blast cells into myeloid cells was confirmed by specific cytochemical stainings, electron microscopy, and an immunologic study. No specific factors in the plasma of the patient promoted the proliferation or differentiation of blast cells. The cellular composition of colonies grown in methylcellulose culture from single blast cells was studied by a micromanipulation technique. High plating efficiency was observed. Of 136 cultures, 78 showed colony growth. Half of the blast cells were colony-forming cells that could proliferate and differentiate into basophils, neutrophils, eosinophils, macrophages, and erythrocytes in the presence of PHA-LCM. Using the blast cells with a high differentiation capacity to the basophil pathway, we studied the effect of recombinant granulocyte-macrophage colony-stimulating factor (GM- CSF). Recombinant GM-CSF support neutrophils, eosinophils, and macrophages but not typical basophils. These findings of the cell differentiation of blast cells into various kinds of cells in vitro were in agreement with the finding of neutrophilia, eosinophilia, basophilia, and thrombocythemia in this patient.  相似文献   
6.
Since 1903, Marchiafava‐Bignami disease has been recognized as a rare syndrome with focal demyelination and necrosis in the corpus callosum, which is usually found in chronic alcoholics. It extends into the neighboring white matter and occasionally as far as the subcortical regions. We report a Japanese patient with Marchiafava‐Bignami disease associated with alcohol abuse, who had traveled around Western Europe, North America and China for more than 30 years. As he suffered extreme delirium in the early stages we administered a low dose (10 mg) of mianserin hydrochloride. He was very irritable and uncooperative on admission, after 20 days his delirium had disappeared and his temper had become very calm and mild. After 40 days, his intelligence level increased substantially as measured by various neuropsychological tests.  相似文献   
7.
Ultrasound registration of the bone surface for surgical navigation.   总被引:4,自引:0,他引:4  
OBJECTIVE: To allow non-invasive registration of the bone surface for computer-assisted surgery (CAS), this investigation reports the development and evaluation of intraoperative registration using 2D ultrasound (US) images. This approach employs automatic segmentation of the bone surface reflection from US images tagged with the 3D position to enable the application of CAS to minimally invasive procedures. METHODS: The US-based registration method was evaluated in comparison to point-based registration, which is the predominant method in current clinical use. The absolute accuracy of the US-based registration was determined using a phantom pelvis, with fiducial registration providing the ground truth. The relative accuracy was determined by an intraoperative study comparing the US registration to the point-based registration obtained as part of the HipNav experimental protocol. RESULTS: The phantom pelvis study demonstrated equivalent accuracy between point- and US-based registration under in vitro conditions. In the intraoperative study, the US-based registration was sufficiently consistent with the point-based registration to warrant larger-scale clinical trials of this non-invasive registration method. CONCLUSION: Ultrasound-based registration eliminates the need for physical contact with the bone surface as in point-based registration. As a result, non-invasive registration could fully unlock the potential of computer-assisted surgery, enabling development of the next generation of minimally invasive surgical procedures.  相似文献   
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Summary The effectiveness of extracranial-intracranial arterial bypass (EC-IC bypass) surgery on impaired haemodynamic status was studied in 12 patients with reduced regional cerebral perfusion pressure (rCPP) and elevated regional oxygen extraction fraction (rOEF) in the area distal to the symptomatic arterial lesion. Postoperative positron emission tomography (PET) study demonstrated a statistically significant decrease of rOEF in the operated hemispheres with disappearance of the pre-operative interhemispheric rOEF difference. Regional cerebral blood flow (rCBF) and regional cerebral oxygen metabolism (rCMRO2) were also increased in the operated hemispheres with disappearance of the pre-operative interhemispheric differences. Regional CBF/regional cerebral blood volume (rCBV) ratios of the symptomatic hemispheres were increased after surgery, but were still lower than in the contralateral hemispheres. We conclude that EC-IC bypass surgery improves impaired cerebral oxygen metabolic reserve.  相似文献   
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