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1.
肌成纤维细胞兼具成纤维细胞和平滑肌细胞的某些特征,来源于局部细胞的增殖,其他细胞的转化及循环中前体细胞的定植,在疤痕形成、肺纤维化等病理过程中发挥重要作用.研究显示其受支气管哮喘相关炎症因子及介质的调控,通过分泌细胞外基质及迁移功能而参与支气管哮喘气道重塑.深入了解肌成纤维细胞在支气管哮喘气道重塑中的作用有助于建立防治...  相似文献   

2.
肌成纤维细胞兼具成纤维细胞和平滑肌细胞的某些特征,来源于局部细胞的增殖,其他细胞的转化及循环中前体细胞的定植,在疤痕形成、肺纤维化等病理过程中发挥重要作用。研究显示其受支气管哮喘相关炎症因子及介质的调控,通过分泌细胞外基质及迁移功能而参与支气管哮喘气道重塑。深入了解肌成纤维细胞在支气管哮喘气道重塑中的作用有助于建立防治气道重塑的新策略。  相似文献   

3.
蒋光  杨远 《国际呼吸杂志》2008,28(21):1321-1324
支气管哮喘(简称哮喘)是以气道慢性炎症和气道重塑为基本特征的慢性疾病.气道重塑的确切机制尚不清楚,目前认为主要与气道慢性炎症有关,上皮损伤及上皮间充质营养单位再活化在气道重塑发病中也起重要作用.治疗哮喘的传统药物对气道重塑作用有限,近年应用抗肿瘤坏死因子α、CpG-ODN、抗IgE抗体和抗Th2细胞因子等免疫调节剂治疗气道重塑,支气管热整形术是有创性治疗技术.  相似文献   

4.
支气管哮喘(简称哮喘)是一种由多种炎症细胞、炎症因子参与的慢性气道炎症性疾病,Th2分化过度在哮喘气道炎症中起重要作用.YKL-40(BRP-39)是新近发现的壳质酶类似物蛋白,参与多种疾病的炎症反应、组织结构重塑等病理过程.YKL-40可通过促进哮喘患者Th2活化、分化并减少其凋亡,增加Th2数量,在哮喘慢性气道炎症中起着重要作用.  相似文献   

5.
张莉莉  尚莉丽 《临床肺科杂志》2012,17(11):2066-2067
支气管哮喘是一种由多种细胞和细胞组分参与的气道慢性炎症性疾病,临床上以气道高反应性与气道重塑为主要特征,而气道重塑是其慢性病程中重要的病理学改变,主要表现为炎症细胞浸润和腺体增生肥大,细胞外基质沉积、基底膜以及气道平滑肌增厚。近年来,气道重塑在哮喘发病中的作用  相似文献   

6.
气道平滑肌在支气管哮喘气道重塑中发生了重要作用.本文就其生物物理学改变,细胞表面离子通道、细胞内钙信号转导的变化,神经调控的特点,以及增殖分泌效应的研究进展作一综述.  相似文献   

7.
气道平滑肌在支气管哮喘气道重塑中发生了重要作用.本文就其生物物理学改变,细胞表面离子通道、细胞内钙信号转导的变化,神经调控的特点,以及增殖分泌效应的研究进展作一综述.  相似文献   

8.
支气管哮喘(简称哮喘)是一种气道慢性炎症,持续的气道炎症导致气道重塑、不完全可逆的气流受限和进行性的肺功能受损.平滑肌细胞的增殖(包括增生和肥大)是哮喘气道重塑的特征性改变,是哮喘气道反应性和严重程度相关的重要因素之一.转化生长因子β(TGF-β)能够诱导分化、炎症、增生以及凋亡等多种细胞反应,促进平滑肌细胞的增生、肥大和迁移,在气道重塑中发挥重要作用.减少TGF-β的产生以及控制TGF-β的效应有利于对慢性哮喘气道重塑的干预治疗.  相似文献   

9.
钙/钙调神经磷酸酶-活化T细胞核因子信号通路作为T细胞内重要的生物信号转导通路,在T细胞活化中起到调节枢纽的作用,与Th细胞的分化及多种细胞因子的产生有密切关系;而T细胞的浸润和活化在支气管哮喘(简称哮喘)气道慢性炎症及气道重塑的发生、发展过程中具有重要的意义,因此,钙/钙调神经磷酸酶-活化T细胞核因子信号通路可能与哮喘的发生有密切关系,其在哮喘T细胞活化机制中的研究对于揭示哮喘的发病机制和治疗有重要的意义.  相似文献   

10.
骨桥蛋白(osteopontin,OPN)是一种多功能的细胞外基质蛋白和免疫调节因子,在多种免疫疾病中表达异常.近期研究发现,OPN作为一种关键的细胞因子在支气管哮喘的发病机制中具有重要的作用,包括调节气道免疫炎症反应、参与气道组织重塑等.研究OPN的作用机制将有利于支气管哮喘发病机制的探索,并为临床治疗提供新的理论依据.  相似文献   

11.
Relying on a certain degree of abstraction, we can propose that no particular distinction exists between animate or living matter and inanimate matter. While focusing attention on some specifics, the dividing line between the two can be drawn. The most apparent distinction is in the level of structural and functional organization with the dissimilar streams of ‘energy flow’ between the observed entity and the surrounding environment. In essence, living matter is created from inanimate matter which is organized to contain internal intense energy processes and maintain lower intensity energy exchange processes with the environment. Taking internal and external energy processes into account, we contend in this paper that living matter can be referred to as matter of dissipative structure, with this structure assumed to be a common quality of all living creatures and living matter in general. Interruption of internal energy conversion processes and terminating the controlled energy exchange with the environment leads to degeneration of dissipative structure and reduction of the same to inanimate matter, (gas, liquid and/or solid inanimate substances), and ultimately what can be called ‘death.’ This concept of what we call dissipative nature can be extended from living organisms to social groups of animals, to mankind. An analogy based on the organization of matter provides a basis for a functional model of living entities. The models relies on the parallels among the three central structures of any cell (nucleus, cytoplasm and outer membrane) and the human body (central organs, body fluids along with the connective tissues, and external skin integument). This three-part structural organization may be observed almost universally in nature. It can be observed from the atomic structure to the planetary and intergalactic organizations. This similarity is corroborated by the membrane theory applied to living organisms. According to the energy nature of living matter and the proposed functional model, the decreased integrity of a human body's external envelope membrane is a first cause of the structural degradation and aging of the entire organism. The aging process than progresses externally to internally, as in single cell organisms, suggesting that much of the efforts towards the restoration and maintenance of the mechanisms responsible for structural development should be focused accordingly, on the membrane, i.e., the skin. Numerous reports indicate that all parts of the human body, like: bones, blood with blood vessels, muscles, skin, and so on, have some ability for restoration. Therefore, actual revival of not only aging tissue of the human body's membrane, but the entire human body enclosed within, with all internal organs, might be expected. We assess several aging theories within the context of our model and provide suggestions on how to activate the body's own anti-aging mechanisms and increase longevity. This paper presents some analogies and some distinctions that exist between the living dissipative structure matter and inanimate matter, discusses the aging process and proposes certain aging reversal solutions.  相似文献   

12.
Abstract: The effect of swimming at night on rat pineal melatonin synthesis was compared with that of light exposure at night. Rats were forced to swim at 0030 hr (lights out at 2000 hr) and sacrificed by decapitation 15 and 30 min later, immediately after swimming. Other groups of animals were exposed to white light (650μW/cm2) for 15 and 30 min at same time. Swimming caused a rapid and highly significant drop in the melatonin content in the pineal gland; however, the activity of N-acetyltransferase (NAT), the supposed rate limiting enzyme in the melatonin production, was not changed. Despite the drop in pineal melatonin levels, serum concentrations of the indole remained elevated in the rats that swam. In contrast, melatonin levels in the pineal and serum of light exposed rats fell precipitously, accompanied by a significant suppression of NAT activity. Since we anticipated that the strenuous exercise associated with swimming may induce release of artrial natriuretic peptide (ANP) from the heart, which in turn could cause the release of pineal melatonin, in a second study we injected physiological saline intravenously to stretch the cardiac muscle and release ANP. Three milliliters of normal saline was injected during the day into the jugular vein of anesthetized rats that were pretreated with isoproterenol to stimulate pineal melatonin production. Animals were killed 15 min after the saline injection, and pineal NAT activity and pineal melatonin levels were measured. The saline injections caused no alteration in the elevated levels of either NAT or melatonin. These data suggest that the disparity in pineal NAT activity (which was high) and pineal melatonin (which was low), in animals swum at night, may not be caused by ANP which is released during strenuous exercise such as swimming.  相似文献   

13.
Abstract: Well-established circadian physiology supports the view that photoperiodic time measurement utilizes the coincidence between the presence of light and a photosensitive phase of a 'biological clock' to alter reproductive status—the so-called external coincidence model of seasonal breeding. In this review, we examine the mechanism whereby photoperiod interacts with presumed suprachiasmatic nuclei activity to allow endogenous melatonin to normally synchronize reproductive activity to the optimal time of year. The Romney Marsh sheep is particularly explored as an experimental model. It is suggested that the on/off activity of seasonal reproduction may be a robust mechanism able to be predictably manipulated by the judicious use of the light/dark cycle and exogenous melatonin, but firmly based on circadian principles.  相似文献   

14.
MUTATION FREQUENCY IN NURSES AND PHARMACISTS WORKING WITH CYTOTOXIC DRUGS   总被引:1,自引:0,他引:1  
Individuals occupationally exposed to cytotoxic drugs may be at risk owing to the effects of these agents on DNA. As an index of DNA damage, in vivo mutations were measured in lymphocytes from 24 oncology nurses or pharmacists and 24 matched controls. Mutation frequency was significantly increased in exposed individuals and appeared to be related to duration of exposure. However, the overall magnitude of the increase was small and its biological significance remains to be determined.  相似文献   

15.
Abstract: The purpose of this study was to determine whether the pineal gland of Turkish hamsters (Mesocricetus brandti) responds to adrenergic agonists with an increase in melatonin production, and, if it does, whether the sensitivity of the pineal gland to agonists would differ throughout the dark phase. Adult Turkish hamsters weighing 110–210 g received a subcutaneous injection of isoproterenol (ISO, 1 mg/kg B.W.) or norepinephrine (NE, 1 mg/kg B.W.) at different times of night. Animals exposed to LD 16:8 responded to ISO or NE with increased pineal melatonin content only when injected at dawn, when endogenous melatonin is at basal or near-basal levels. When the 8 hr scotophase was entirely replaced with light, the responsiveness to ISO injections at dawn disappeared. In animals exposed to light from 30 min prior to injection to the time of sacrifice, ISO injections increased pineal melatonin content (P < 0.005, three-way ANOVA), which varied, depending on the specific time of injection (effect of time of night, P < 0.05, three-way ANOVA). These results demonstrate that (1) adrenergic agonists enhance the production of pineal melatonin in Turkish hamsters, (2) this stimulatory effect takes place late, but not early in the 8 hr scotophase, and (3) the adrenergic induction of pineal melatonin production in Turkish hamsters requires priming by darkness during the appropriate circadian phase.  相似文献   

16.
The past decade has witnessed dramatic decreases in malaria‐associated mortality and morbidity around the world. This progress has largely been due to intensified malaria control measures, implementation of rapid diagnostics and establishing a network to anticipate and mitigate antimalarial drug resistance. However, the ultimate tool for malaria prevention is the development and implementation of an effective vaccine. To date, malaria vaccine efforts have focused on determining which of the thousands of antigens expressed by Plasmodium falciparum are instrumental targets of protective immunity. The antigenic variation and antigenic polymorphisms arising in parasite genes under immune selection present a daunting challenge for target antigen selection and prioritization, and is a given caveat when interpreting immune recall responses or results from monovalent vaccine trials. Other immune evasion strategies executed by the parasite highlight the myriad of ways in which it can become a recurrent infection. This review provides an update on immune effector mechanisms in malaria and focuses on our improved ability to interrogate the complexity of human immune system, accelerated by recent methodological advances. Appreciating how the human immune landscape influences the effectiveness and longevity of antimalarial immunity will help explain which conditions are necessary for immune effector mechanisms to prevail.  相似文献   

17.
Aorto-duodenal fistulae (ADF) are the most frequent aorto-enteric fistulae (80%), presenting with upper gastrointestinal bleeding. We report the first case of a man with a secondary aorto-duodenal fistula presenting with a history of persistent occlusive syndrome. A 59-year old man who underwent an aortic-bi-femoral bypass 5 years ago, presented with dyspepsia and biliary vomiting. Computed tomography scan showed in the third duodenal segment the presence of inflammatory tissue with air bubbles between the duodenum and prosthesis, adherent to the duodenum. The patient was submitted to surgery, during which the prosthesis was detached from the duodenum, the intestine failed to close and a gastro-jejunal anastomosis was performed. The post-operative course was simple, secondary ADF was a complication (0.3%-2%) of aortic surgery. Mechanical erosion of the prosthetic material into the bowel was due to the lack of interposed retroperitoneal tissue or the excessive pulsation of redundantly placed grafts or septic procedures. The third or fourth duodenal segment was most frequently involved. Diagnosis of ADF was difficult. Surgical treatment is always recommended by explorative laparotomy. ADF must be suspected whenever a patient with aortic prosthesis has digestive bleeding or unexplained obstructive syndrome. Rarely the clinical picture of ADF is subtle presenting as an obstructive syndrome and in these cases the principal goal is to effectively relieve the mechanical bowel obstruction.  相似文献   

18.
Objectives Peripartal transmission of human immunodeficiency virus (HIV) and Treponema pallidum, the causative agent of syphilis, leads to severe consequences for newborns. Preventive measures require awareness of the maternal infection. Although HIV and syphilis testing in Madagascar could be theoretically carried out within the framework of the national pregnancy follow‐up scheme, the required test kits are rarely available at peripheral health centres. In this study, we screened blood samples of pregnant Madagascan women for HIV and syphilis seroprevalence to estimate the demand for systemic screening in pregnancy. Methods Retrospective anonymous serological analysis for HIV and syphilis was performed in plasma samples from 1232 pregnant women that were taken between May and July 2010 in Ambositra, Ifanadiana, Manakara, Mananjary, Moramanga and Tsiroanomandidy (Madagascar) during pregnancy follow‐up. Screening was based on Treponema pallidum haemagglutination tests for syphilis and rapid tests for HIV, with confirmation of positive screening results on line assays. Results Out of 1232 pregnant women, none were seropositive for HIV and 37 (3%) were seropositive for Treponema pallidum. Conclusions Our findings are in line with previous studies that describe considerable syphilis prevalence in the rural Madagascan population. The results suggest a need for screening to prevent peripartal Treponema pallidum transmission, while HIV is still rare. If they are known, Treponema pallidum infections can be easily, safely and inexpensively treated even in pregnancy to reduce the risk of transmission.  相似文献   

19.
20.
Objectives To quantify the risk of infection and disease in spouses of tuberculosis patients and the extent to which intervention could reduce the risk in this highly exposed group. Methods We compared HIV prevalence, TB prevalence and incidence and tuberculin skin test (TST) results in spouses of TB patients and community controls. HIV‐positive spouses were offered isoniazid preventive therapy (IPT), and TST was repeated at 6, 12 and 24 months. Results We recruited 148 spouses of smear‐positive patients ascertained prospectively and 3% had active TB. We identified 203 spouses of previously diagnosed smear‐positive patients, 11 had already had TB, and the rate of TB was 2.4 per 100 person years(py) over 2 years (95% CI 1.15–5.09). 116 were found alive and recruited. HIV prevalence was 37% and 39% in the prospective and retrospective spouse groups and 17% in controls. TST was ≥10 mm in 80% of HIV negative and in 57% of HIV‐positive spouses ascertained retrospectively; 74% HIV negative and 62% HIV‐positive spouses ascertained prospectively, and 48% HIV negative and 26% HIV‐positive community controls. Of 54 HIV‐positive spouses, 18 completed 6‐month IPT. At 2 year follow‐up, 87% of surviving spouses had TST ≥10 mm and the rate of TB was 1.1 per 100 py (95% CI 0.34–3.29). Conclusions Spouses are a high‐risk group who should be screened for HIV and active TB. TST prevalence was already high by the time the spouses were approached but further infections were seen to occur. Uptake and adherence to IPT was disappointing, lessening the impact of short‐duration therapy.  相似文献   

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