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71.
Bovine paratuberculosis is a highly prevalent chronic infection of the small intestine in cattle, caused by Mycobacterium avium subspecies paratuberculosis (MAP). In earlier studies we showed the protective effect of Hsp70/DDA subunit vaccination against paratuberculosis. In the current study we set out to measure primary immune responses generated at the site of Hsp70 vaccination. Lymph vessel cannulation was performed to obtain efferent lymph from the prescapular lymph node draining the neck area where the vaccine was applied. Hsp70 vaccination induced a significant increase of CD21+ B cells in efferent lymph, accounting for up to 40% of efferent cells post-vaccination. Proliferation (Ki67+) within the CD21+ B cell and CD4+ T cell populations peaked between day 3 and day 5 post-vaccination. From day 7, Hsp70-specific antibody secreting cells (ASCs) could be detected in efferent lymph. Hsp70-specific antibodies, mainly of the IgG1 isotype, were also detected from this time point onwards. However, post-vaccination IFN-γ production in efferent lymph was non-sustained. In conclusion, Hsp70-vaccination induces only limited Th1 type immune responsiveness as reflected in efferent lymph draining the vaccination site. This is in line with our previous observations in peripheral blood. The main primary immunological outcome of the Hsp70/DDA subunit vaccination is B cell activation and abundant Hsp70-specific IgG1 production. This warrants the question whether Hsp70-specific antibodies contribute to the observed protective effect of Hsp70 vaccination in calves. 相似文献
72.
73.
Lifespan extension of Drosophila melanogaster through hormesis by repeated mild heat stress 总被引:3,自引:0,他引:3
We assessed the impact of repeated episodes of a mild heat stress on lifespan, fecundity, heat stress resistance and Hsp70
expression in Drosophila melanogaster. There was a significant increase in lifespan of females repeatedly exposed to a mild heat stress when measured in both a
pair and a group situation. There was no effect on fecundity when the flies were first exposed to the mild heat stress at
an age later than 3 days old, but when it did occur on day 3, there was a significant effect on cumulative fecundity levels
over 18 days. The negative fitness effect appears to be the result of a direct cessation or reduction of oviposition during
the first bout of stress exposure, and is influenced by the age at which this first exposure occurs. The mild heat stress
had no impacton egg viability. The mild heat stress exposures increased resistance to potentially lethal heat stress and levels
of Hsp70 expression in heat-exposed flies were higher than those in controls.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
74.
BACKGROUND: A pleural drainage system must be capable of efficiently evacuating the air or fluids from the pleural cavity so that adequate lung reexpansion can take place. The air flow and negative pressure of the system will depend on the particular design of each model. This experimental study analyzes the specifications and performance of the pleural drainage systems currently on the market. METHODS: Thirteen models of pleural drainage systems connected to wall suction were examined. The models were classified into the following three groups: dry systems; wet systems; and single-chamber systems. We determined the ambient air flow and the negative pressure generated according to the suction level. The components of each model are also described. RESULTS: Under normal conditions, dry (except for the Sentinel Seal; Sherwood Medical; Tullamore, Ireland), wet, and single-chamber systems reach similar air flow rates (17 to 30, 24 to 27, and 22 to 28 L/min, respectively). With higher wall suction levels, wet systems increase the air flow (26 to 49 L/min) but the negative pressure becomes unstable because of the water loss phenomenon, dry systems increase the air flow (29 to 50 L/min) without modifying the regulator pressure, and single-chamber systems also raise the air flow (45 to 51 L/min) but increase the negative pressure. When there is an air leak, dry systems (except for the Sentinel Seal) lose less negative pressure than the other systems. CONCLUSIONS: The functioning of these systems can be optimized only by applying a suitable wall suction level adjusted to each case. Although the three types of systems are capable of evacuating adequate air flow rates, the negative pressure and the capacity to maintain it in the presence of an air leak are different in each system. Being fitted with valves and not water compartments makes the dry systems the safest and the ideal for use when the patient has to be moved. 相似文献
75.
76.
To compare the clinical efficacy of sodium hyaluronate eye drops, polyethylene glycol eye drops, and compound dextran eye drops in the treatment of dry eye after phacoemulsification of cataract.A total of 99 patients with dry eye after cataract phacoemulsification combined with intraocular lens implantation were treated in our hospital. Patients were divided into group A (sodium hyaluronate eye drops), group B (polyethylene glycol eye drops), and group C (dextran-70 eye drops). The clinical effect, tear film breakup time, basic tear secretion, corneal staining score, dry eye symptom score, and the incidence of ocular irritation were assessed.On the 3rd, 15th, 30th, and 60th day after operation, the tear film breakup time, corneal staining score, Schirmer I test, and dry eye symptom score in group A and group B were better than those in group C (P < .05). In addition, there were no significant differences in tear breakdown time, corneal staining score, Schirmer I test, and dry eye symptom score between group A and group B (P > .05). At 3 days to 60 days after operation, the incidence of dry eye in group A (12.12%) and group B (18.18%) was lower than that in group C (39.39%), and the incidence of dry eye in group A was significantly lower than that in group B (P < .05).The effect of sodium hyaluronate eye drops elicited a greater beneficial impact as compared to polyethylene glycol eye drops and dextran-70 eye drops. 相似文献
77.
Yan Gao Shi-feng Chu Jian-ping Li Zhao Zhang Jia-qing Yan Zhi-lin Wen Cong-yuan Xia Zheng Mou Zhen-zhen Wang Wen-bin He Xiao-feng Guo Gui-ning Wei Nai-hong Chen 《Acta pharmacologica Sinica》2015,36(3):311-322
Aim:
Protopanaxtriol (Ppt) is extracted from Panax ginseng Mayer. In the present study, we investigated whether Ppt could protect against 3-nitropropionic acid (3-NP)-induced oxidative stress in a rat model of Huntington''s disease (HD) and explored the mechanisms of action.Methods:
Male SD rats were treated with 3-NP (20 mg/kg on d 1, and 15 mg/kg on d 2–5, ip). The rats received Ppt (5, 10, and 20 mg/kg, po) daily prior to 3-NP administration. Nimodipine (12 mg/kg, po) or N-acetyl cysteine (NAC, 100 mg/kg, po) was used as positive control drugs. The body weight and behavior were monitored within 5 d. Then the animals were sacrificed, neuronal damage in striatum was estimated using Nissl staining. Hsp70 expression was detected with immunohistochemistry. Reactive oxygen species (ROS) generation was measured using dihydroethidium (DHE) staining. The levels of components in the Nrf2 pathway were measured with immunohistochemistry and Western blotting.Results:
3-NP resulted in a marked reduction in the body weight and locomotion activity accompanied by progressive striatal dysfunction. In striatum, 3-NP caused ROS generation mainly in neurons rather than in astrocytes and induced Hsp70 expression. Administration of Ppt significantly alleviated 3-NP-induced changes of body weight and behavior, decreased ROS production and restored antioxidant enzymes activities in striatum. Moreover, Ppt directly scavenged free radicals, increased Nrf2 entering nucleus, and the expression of its downstream products heme oxygenase-1 (HO-1) and NAD(P)H quinone oxidase 1 (NQO1) in striatum. Similar effects were obtained with the positive control drugs nimodipine or NAC.Conclusion:
Ppt exerts a protective action against 3-NP-induced oxidative stress in the rat model of HD, which is associated with its anti-oxidant activity. 相似文献78.
本文构建并表达了旋毛虫热休克蛋白70(Ts-Hsp70)与排泄分泌抗原Ts87的融合蛋白,并对融合蛋白进行纯化和免疫学鉴定。本研究采用限制性内切酶EcoRⅠ酶切位点将目的基因Ts-Hsp70与Ts87相连接,插入pET28-a (+)质粒,转入大肠埃希菌BL21(DE3)中诱导表达、纯化,获得的融合蛋白rTs-Hsp70-Ts87用Western blot的方法鉴定。经PCR、酶切鉴定、测序分析,结果显示,目的基因片段大小为2721 bp,构建的重组质粒与预期相符。经IPTG诱导表达,通过镍离子柱层析纯化复性后得到可溶的融合蛋白rTs-Hsp70-Ts87,其相对分子质量约为100 kDa; Western blot结果显示,该蛋白可被抗His标签单抗、 rTs-Hsp70免疫血清、 rTs87免疫血清识别。以上结果表明,本研究成功构建并表达了融合蛋白rTs-Hsp70-Ts87,为进一步研究rTs-Hsp70-Ts87的免疫保护性,开发新的有效抗旋毛虫病的疫苗奠定基础。 相似文献
79.
STUDY OBJECTIVES: Despite the success of specialist cough clinics, there is increasing recognition of a subgroup of chronic coughers in whom a diagnosis cannot be made even after thorough, systematic investigation. We call this condition chronic idiopathic cough (CIC). The aim of this study is to compare the clinical characteristics of CIC patients with those of coughers in whom a diagnosis has been established (non-CIC) to see if there is a recognizable clinical pattern that distinguishes CIC from non-CIC. DESIGN: Retrospective analysis of the medical records of chronic cough patients. SETTING: The Royal Brompton Hospital Chronic Cough Clinic, London. PATIENTS: One hundred patients with chronic cough referred to the Royal Brompton Hospital Cough Clinic between October 2000 and February 2004. RESULTS: Seventy-one percent of all patients were female. Median age was 57 years (range, 19 to 81 years), with a median duration of symptoms of 48 months (range, 2 to 384 months). The primary diagnoses were CIC (42%), postnasal drip syndromes (22%), gastroesophageal reflux disease (16%), asthma (7%), and others (13%). In CIC patients, the median age at referral, age at onset of cough, and proportion of females did not differ significantly from non-CIC patients. CIC patients had a longer median duration of cough (72 months vs 24 months, p = 0.002), were more likely to report an upper respiratory tract infection (URTI) as the initial trigger of their cough (48% vs 24%, p = 0.0014), and had a significantly lower cough threshold in response to capsaicin (log concentration of capsaicin required to induce five or more coughs, - 0.009 vs 0.592, p = 0.032) than non-CIC patients. CONCLUSIONS: Patients with CIC commonly describe a URTI that initiates their cough, which then lasts for many years, and they demonstrate an exquisitely sensitive cough reflex. We believe that CIC may be a distinct clinical entity with an as-yet unidentified underlying pathology. 相似文献
80.
Feller-Kopman D Lukanich JM Shapira G Kolodny U Schori B Edenfield H Temelkuran B Ernst A Schindel Y Fink Y Fox J Bueno R 《Chest》2008,133(4):892-896
BACKGROUND: Thermal ablation is one of the most commonly used modalities to treat central airway obstruction. Both laser and argon plasma coagulation (APC) have been reported to cause gas emboli and cardiac arrest. We sought to determine whether bronchoscopic ablation therapy can result in systemic gas emboli, correlate their presence with the rate of gas flow, and establish whether a zero-flow (ZF) modality would result in the significant reduction or elimination of emboli. METHODS: CO(2) laser delivered through a photonic bandgap fiber (PBF) and APC were applied in the trachea and mainstem bronchi of six anesthetized sheep at varying dosages and gas flow rates. Direct epicardial echocardiography was used to obtain a four-chamber view and detect gas emboli. RESULTS: The presence of gas flow accompanying APC and the CO(2) laser with forward flow correlated significantly with the appearance of gas bubbles in the atria. A definite dose response was observed between the gas flow rate and the number of bubbles seen. When the CO(2) laser was delivered through a PBF with ZF to the trachea or bronchi, no bubbles were observed. CONCLUSION: Bronchoscopic thermal ablation therapy using gas flow is associated with gas emboli in a dose-dependent fashion. The use of the flexible PBF with ZF is not associated with the development of gas emboli. Further study is required to determine whether a clinically safe threshold of gas emboli exists, and the relationships among the pathologic depth of tissue destruction, gas flow, pulse duration, and the development of gas emboli. 相似文献