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The sneeze reflex is a valuable tool for exploring the maturation of the respiratory control in the newborn as it alters both inspiratory and expiratory activities. Air puff stimulation of the superior nasal meatus innervated by ethmoidal afferents consistently evokes sneeze in adult cats. Such stimulation evokes only a reinforcement of expiratory activities in newborn kittens. This study demonstrates that the pattern of Fos-like immunoreactivity evoked by nasal stimulation changes during functional maturation of sneeze. Nasal stimulation evoked immunoreactivity (i) in the trigeminal sensory complex, at the levels where nasal afferents project, (ii) in the reticular formation, (iii) in the solitary complex and (iv) in the parabrachial area of mature kittens. The evoked immunoreactivity was the same in newborn kittens as in mature kittens in the projection areas of the nasal primary afferents. Fos response was less than half that in mature kittens in the reticular formation and absent in the solitary complex or the parabrachial area. Sneeze can be elicited from the time when evoked immunoreactivity in the solitary complex and the parabrachial area is above control levels. These data provide evidence that the maturation of sneeze is dependent on the development of central relays allowing peripheral inputs to be integrated by neurons engaged in respiratory control. 相似文献
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136.
Casein kinase II (CK2) enhances death-inducing signaling complex (DISC) activity in TRAIL-induced apoptosis in human colon carcinoma cell lines 总被引:2,自引:0,他引:2
Protein kinase casein kinase II (CK2) is increased in response to diverse growth stimuli, as well as being elevated in many human cancers examined. We have demonstrated that CK2 is a key survival factor that protects human colon carcinoma cells from TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis. We determined that inhibition of CK2 phosphorylation events by DRB (5,6-dichlorobenzimidazole) resulted in dramatic sensitization of tumor cells to TRAIL-induced apoptosis, in the absence of effects in normal cells. Sensitization was caspase dependent, and independent of regulation via NF-kappaB. Further, inhibition of phosphorylation by CK2 did not modify the expression level of antiapoptotic proteins. Analysis of TRAIL-induced death-inducing signaling complex (DISC) formation demonstrated enhanced formation of the DISC, enhanced cleavage of caspase-8 and cleavage of Bid in the presence of DRB, thereby facilitating the release of proapoptotic factors from the mitochondria with subsequent downregulation of the expression of XIAP and c-IAP1. Further, silencing of CK2alpha in HT29 cells following transfection of CK2alpha shRNA abrogated CK2 kinase activity while simultaneously increasing TRAIL sensitivity. These findings demonstrate that CK2 plays a critical antiapoptotic role by conferring resistance to TRAIL at the level of the DISC. 相似文献
137.
Detection of JC virus DNA sequences and expression of viral T antigen and agnoprotein in esophageal carcinoma 总被引:4,自引:0,他引:4
Del Valle L White MK Enam S Piña Oviedo S Bromer MQ Thomas RM Parkman HP Khalili K 《Cancer》2005,103(3):516-527
BACKGROUND: The human polyomavirus JC virus (JCV) causes progressive multifocal leukoencephalopathy. Subclinical infection with JCV occurs in 85-90% of the population worldwide. The virus usually remains latent but can reactivate under immunosuppressive conditions, resulting in progressive multifocal leukoencephalopathy. JCV is oncogenic in experimental animals and is associated with human brain tumors. JCV is found in normal mucosa of the gastrointestinal tract, and some colon carcinomas express the oncogenic JCV T-antigen protein. The objective of this study was to examine the presence of JCV DNA sequences and JCV protein expression in normal and malignant human esophageal tissues. METHODS: The authors examined the presence of JCV DNA sequences and protein expression in normal and malignant human esophageal tissues. Seventy well characterized biopsy specimens from patients with a spectrum of esophageal disorders were studied by immunohistochemistry, and 18 specimens were analyzed further by polymerase chain reaction amplification. RESULTS: JC viral DNA was isolated from 11 of 13 normal esophageal biopsy specimens (85%) and from 5 of 5 esophageal carcinomas (100%). Using immunohistochemistry, JCV T antigen was detected in 10 of 19 carcinomas (53%), agnoprotein was detected in 8 carcinomas (42%), p53 tumor suppressor was detected in 11 carcinomas (58%), and beta-catenin was detected in 4 carcinomas (21%). Zero of 51 normal, benign, and premalignant esophageal samples expressed viral proteins. Laser-capture microdissection verified the presence and specificity of JCV DNA sequences. beta-Catenin and p53 were colocalized with JCV T-antigen in the nuclei of neoplastic cells. CONCLUSIONS: The results provide evidence for infection of gastrointestinal tract cells by JCV and suggest a potential role of JCV in the development of upper digestive tract carcinomas. 相似文献
138.
OBJECTIVES: sedation is central to the management of intensive care patients. The aim of this study was to establish the current sedation practice in Maghrebian intensive care units (ICUs). The use of sedation policies with or without a written protocol, the use of scoring systems, the influence of costs on drug choice, the most common drugs for sedation and the use of neuromuscular blocking agents. METHODS: a self-administered questionnaire composed of 20 items was sent to 138 intensivists in the Maghreb working in 25 teaching hospitals and 16 private clinics. RESULTS: 50 of 138 questionnaires were returned (response rate = 36.2%). Midazolam and Fentanyl were the main sedative agents used (respectively 98% and 87%) less than 14% of the ICUs used the Propofol mainly in the first 48 hours. A sedation policy was adopted in 63.6% with a written protocol in 20% of cases. Sedation scoring systems were noted in 14.3% of cases (RAMSAY scale in 100%). Economic aspect was important for 64.6% of ICUs. DISCUSSION: sedation may seem secondary in the initial management of intensive care patients, only 63% of our respondents had a sedation policy and 20% a written protocol though its use is thought to improve outcome and reduce costs. Economic aspect was important for the choice of the drug to use (64%), this may explain the preferential use of Midazolam 98% in association with an analgesic (Fentanyl: 85%) while Propofol is used only in 14% though pharmacoeconomic studies may be in fact in favor of the latter. Neuromuscular blocking agents are less frequently used (16%) mainly because of the risk of complications. 相似文献
139.
Chordoma is a locally invasive tumor of low metastatic potential. Only six cases of chordoma that metastasized to the brain are found in the English literature. Most of these lesions were clinically silent and all were associated with extraneural metastases. The authors report a case of symptomatic brain metastasis from a sacrococcygeal chordoma in the absence of other metastases. The incidence, sites, and factors predictive of chordoma metastasis are discussed. 相似文献
140.
Transcatheter arterial chemoembolization in unresectable cholangiocarcinoma: initial experience in a single institution 总被引:6,自引:0,他引:6
Burger I Hong K Schulick R Georgiades C Thuluvath P Choti M Kamel I Geschwind JF 《Journal of vascular and interventional radiology : JVIR》2005,16(3):353-361
PURPOSE: Unresectable cholangiocarcinoma carries a dismal prognosis, with median survival times ranging from 6 to 12 months from the time of diagnosis. Palliative therapies have been disappointing and have not been shown to significantly prolong survival. Conversely, transcatheter arterial chemoembolization (TACE) has been effective in prolonging the lives of patients with hepatocellular carcinoma but has not been used against cholangiocarcinoma. Therefore, the purpose of the present study was to assess the safety and efficacy (ie, survival) of TACE in patients with unresectable intrahepatic cholangiocarcinoma. MATERIALS AND METHODS: Seventeen patients with unresectable cholangiocarcinoma were treated with one or more cycles of TACE between 1995 and 2004 at our institution. Follow-up imaging was performed on all patients 4-6 weeks after each TACE procedure to determine tumor response and need for further treatment. Survival was calculated with use of the Kaplan-Meier survival curve. RESULTS: The median survival for 17 patients treated with TACE was 23 months. Two patients with previously unresectable disease underwent successful resection after TACE. The procedure was well tolerated by 82% of the patients, who experienced no side effects or mild side effects that quickly resolved with conservative therapy alone. Two patients had minor complications (12%), which were managed successfully, and one had a major complication that resulted in a fatal outcome. This patient had a rapidly declining course from the time of diagnosis and died shortly after TACE. CONCLUSIONS: The results suggest that TACE was effective at prolonging survival of patients with unresectable cholangiocarcinoma. Therefore, for these patients, TACE may be an appropriate palliative therapy. 相似文献