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1.
As peripheral blood monocytes (PBM) differentiate into tissue macrophages, they undergo a variety of functional changes. One such difference which has been described is an enhanced metabolism of arachidonic acid (AA) via the 5-lipoxygenase (5-LO) pathway in alveolar macrophages (AM) as compared to PBM. In order to elucidate a possible mechanism for this difference, we compared the metabolism of endogenously released AA mobilized by agonists and of exogenously supplied fatty acid in adherent autologous PBM and AM obtained from six normal subjects. Exogenous AA was metabolized to larger amounts of both cyclooxygenase (CO) and 5-LO products by PBM as compared with AM. Although the two cell types released similar amounts of endogenous AA in response to ionophore A23187, marked differences in the pattern of its metabolism were observed. In PBM, a large proportion of released AA remained unmetabolized, and that which was metabolized was converted predominantly to CO products. In contrast, arachidonate released by AM was efficiently metabolized, predominantly via the 5-LO pathway. Similar results were obtained when cells were stimulated with the particulate zymosan, with PBM synthesizing mainly CO and AM, mainly 5-LO eicosanoids. In addition, culture of PBM for up to 5 days in an aerobic environment did not alter their response to A23187 stimulation. These results suggest that the lesser 5-LO metabolism by PBM than AM is not explained by lesser phospholipase or 5-LO activities, but rather a compartmentalization of the endogenous AA deacylated by phospholipase and the 5-LO enzyme in the PBM. The acquisition of the capacity to metabolize endogenous AA to large quantities of 5-LO products as mononuclear phagocytes differentiate in the lung may equip them with the ability to mount an inflammatory response in the alveolar space.  相似文献   

2.
输血是现代医学中重要的抢救、治疗手段,临床输血是一门极其复杂的学科。血液及其制品的管理是一项科学的系统工程,是保证血液质量、提高医疗用血效率、促进输血事业和科研技术水平不断发展的关键。输血科是医院的重要部门,具体负责临床用血的技术指导和技术实施,确保贮血、配发血和其他科学、合理用血措施的执行,其基本目的是将血液及成分安全、有效、合理而便宜的输注给需要的病人并取得疗效。输血科如何履行好职能,保证临床输血安全、科学、合理、有效,已成为当前基层医院首先需要解决的问题。本文就基层医院输血科的工作状况进行了分析,并提出完善规章制度,严格执行操作,更新输血观念,科学合理用血,开展业务新技术,保证输血有效性等相应整改措施,在实际运行中取得可喜的成绩。  相似文献   

3.
The presence of distinct cytolytic subsets within interleukin-2-expanded peripheral blood leukocytes (IEL) cultures was demonstrated by clonal analysis. Thirty-seven IEL clones were isolated from two healthy blood donors; 21 destroyed both Daudi and K562 cell lines. Of those 21 clones, 1 clone could destroy autologous PBM, 7 clones could destroy fresh allogeneic ovarian carcinoma (OVA-CA) cells, and 6 clones could destroy normal autologous PBM and fresh OVA-CA cells. Twelve of the 37 clones destroyed only one of the four targets tested: 8 clones destroyed K562, 2 clones destroyed Daudi, and 1 clone each was selective for autologous PBM or OVA-CA. Of the remaining 4 clones, 1 destroyed OVA-CA and Daudi cells, 1 destroyed PBM and K562, 1 destroyed PBM and Daudi cells, and 1 destroyed PBM, Daudi, and OVA-CA. These results suggest that these functionally heterogeneous cytolytic clones may use different cell recognition or cytolytic mechanisms to enable these distinct and, at times, reciprocal patterns of target cell selectivity.  相似文献   

4.
Neuroinflammation is an important pathogenesis of Parkinson’s disease (PD). The peripheral immune system could produce profound effects on central immunities. The peripheral blood monocyte (PBM) immune tolerance is the refractoriness of immune system to avoid overactive peripheral inflammation. The PBM are also actively involved in central immune activities. There is evidence implying the probable failure of immune tolerance and impairment of CD200/CD200R signaling in PD patients. Here we aimed to explore the effects of PBM tolerance in peripheral LPS-induced neuroinflammation as well as the specific roles of CD200/CD200R pathway in PBM tolerance. We found that repeated intraperitoneal administration of 0.3 mg/kg LPS was able to induce the PBM tolerance. PBM tolerance reduced peripheral LPS-induced elevation of serum TNF-α, IL-1β expression and TLR4 expression in PBM. PBM tolerance and PBM depletion alleviated peripheral LPS-induced neuroinflammation demonstrated by reduced proinflammatory cytokines in brain and blocked microglia activation. The CD200R expression in PBM was upregulated in PBM tolerance group after intraperitoneal administration of high-dose LPS in vivo and the blockade of CD200/CD200R interaction induced the failure of PBM tolerance in vitro. These results suggested the PBM tolerance could attenuate the peripheral LPS-induced neuroinflammation via upregulating the CD200R expression and the CD200/CD200R signaling played a key role in PBM tolerance. Effective regulation of the PBM in periphery may be a potential way to limit neuroinflammation while the CD200R on PBM could be used as a potential therapeutic target to alleviate neuroinflammation.  相似文献   

5.
For several decades, the FDA has undertaken many initiatives to improve the quality and safety of sterile drug products. In recent years, efforts have also been undertaken to accelerate the rate for application approval by adding earlier involvement of microbiology reviewers in drug development. Product and manufacturing process development, as well as safe use and product design, are among the elements of enhanced technical involvement. An overview of the product quality microbiology aspects for sterile drugs is provided.  相似文献   

6.
Foodborne botulism is caused by consumption of preformed botulinum neurotoxin, with as little as 30 ng of neurotoxin being potentially lethal. Consumption of minute quantities of neurotoxin-containing food can result in botulism. In view of the severity of foodborne botulism, it is essential that new foods be developed safely without an increase in incidence of this disease. Minimally heated, chilled foods are a relatively new type of food, sales of which are currently increasing by about 10% per annum. These products meet consumer demand for high-quality foods that require little preparation time. Their safety and quality depends on mild heat treatment, chilled storage, restricted shelf life and sometimes on intrinsic properties of the foods. The principal microbiological hazard is nonproteolytic Clostridium botulinum, and there is a concern that this may become an emerging issue. A considerable amount of research and development over the last 15 years has underpinned the safe production of commercial, minimally heated, chilled foods with respect to foodborne botulism, and it is essential that safe food continues to be developed. In particular, the desire to use lighter heat processes and a longer shelf life presents a challenge that will only be met by significant developments in quantitative microbiological food safety.  相似文献   

7.
Ferric ammonium citrate (FAC) is nonmitogenic for human peripheral blood mononuclear cells (PBM) but has a potent mitogenic activity in the presence of IL-2. FAC in the presence of IL-2 increases the number of human peripheral blood mononuclear cells (PBM) expressing receptors for IL-2 and transferrin. FAC also markedly stimulates human PBM treated with supraoptimal, nonmitogenic concentrations of Con A. FAC, in the presence of IL-2, is a T-cell mitogen with a stringent requirement for macrophages. FAC stimulates the production of TNF-alpha and IFN-gamma in human PBM, and this effect is potentiated by IL-2. Thiourea and 3-amino-1,2,4-triazole selectively inhibit mitogenesis induced by FAC, indicating that oxygen radicals or peroxidase may mediate the triggering signal induced by this mitogen. In addition to hemin, as we have previously reported, and FAC, a variety of iron-containing proteins have lymphocyte stimulatory properties in combination with IL-2. They include horseradish peroxidase, cytochrome c, myoglobin, and transferrin. We have given the name ferro-mitogens to this group of compounds.  相似文献   

8.
Blood Transfusion Safety is dependent on effectively organised and managed blood services, which have adequate financial resources, skilled manpower, appropriate infrastructure and quality management systems in place.80% of the world's population has access to 20% of the supply blood products, of which little is consistently safe.HIV highlighted the importance of blood safety. The lack of effective blood services in low human development index (LHDI), developing countries, has lead to international funding and capacity building for more than three decades. The initial strategies focused on providing HIV testing reagents to prevention transmission, however this only addresses one part of blood safety.Blood safety is not only dependent on preventing HIV transmission. In many populations there are other infectious agents, which have a higher prevalence. Ensuring the correct blood is provided to the patient depends on: well managed services with effective leadership and adequate budgets; capacity building and retention of skilled experienced staff; availability of laboratory equipment, correctly maintained; blood cold chain systems; procedures for tendering, purchasing and ensuring an unbroken supply of reagents and consumables; and quality management systems.Barriers for simplified effective tendering, procurement and contracting require urgent attention and coordination of all funding organisations to ensure an unbroken supply of reagents.  相似文献   

9.
The use of dermal substitutes to treat skin defects such as ulcers has shown promising results, suggesting a potential role for skin substitutes for treating acute and chronic wounds. One of the main drawbacks with the use of dermal substitutes is the length of time from engraftment to graft take, plus the risk of contamination and failure due to this prolonged integration. Therefore, the use of adjuvant energy‐based therapeutic modalities to augment and accelerate the rate of biointegration by dermal substitute engraftments is a desirable outcome. The photobiomodulation (PBM) therapy modulates the repair process, by stimulating cellular proliferation and angiogenesis. Here, we evaluated the effect of PBM on a collagen‐glycosaminoglycan flowable wound matrix (FWM) in an ex vivo human skin wound model. PBM resulted in accelerated rate of re‐epithelialization and organization of matrix as seen by structural arrangement of collagen fibers, and a subsequent increased expression of alpha‐smooth muscle actin (α‐SMA) and vascular endothelial growth factor A (VEGF‐A) leading to an overall improved healing process. The use of PBM promoted a beneficial effect on the rate of integration and healing of FWM. We therefore propose that the adjuvant use of PBM may have utility in enhancing engraftment and tissue repair and be of value in clinical practice.   相似文献   

10.
两株菌对氯氰菊酯及其降解产物3-PBA的协同代谢研究   总被引:10,自引:1,他引:9  
以两株降解菌为材料,研究了它们对氯氰菊酯及其代谢中间产物3-苯氧基苯甲酸(3-PBA)的协同降解过程。在有3-PBA存在时,氯氰菊酯降解菌CDT3(Rhodococcus sp.)的生长会受到明显的抑制;低于200mg/L的氯氰菊酯对3-PBA降解菌PBM11(Pesudomonas sp.)的生长无显著影响。同时加入菌株CDT3和PBM11时,氯氰菊酯的降解速率较单独加入菌株CDT3时有所提高。菌株PBM11的菌数随氯氰菊酯和3-PBA的降解而增加,但CDT3的数量没有明显的增加。同时加入菌株CDT3和PBM11的处理中观察不到3-PBA的积累,在后加入PBM11的处理中可观察到24h内明显有3-PBA的积累,加入菌株PBM11后,3-PBA可被迅速降解。  相似文献   

11.
The production of biopharmaceuticals requires highly sophisticated, complex cell based processes. Once a process has been developed, acceptable ranges for various control parameters are typically defined based on process characterization studies often comprising several dozens of small scale bioreactor cultivations. A lot of data is generated during these studies and usually only the information needed to define acceptable ranges is processed in more detail. Making use of the wealth of information contained in such data sets, we present here a methodology that uses performance data (such as metabolite profiles) to forecast the product quality and quantity of mammalian cell culture processes based on a toolbox of advanced statistical methods. With this performance based modeling (PBM) the final product concentration and 12 quality attributes (QAs) for two different biopharmaceutical products were predicted in daily intervals throughout the main stage process. The best forecast was achieved for product concentration in a very early phase of the process. Furthermore, some glycan isoforms were predicted with good accuracy several days before the bioreactor was harvested. Overall, PBM clearly demonstrated its capability of early process endpoint prediction by only using commonly available data, even though it was not possible to predict all QAs with the desired accuracy. Knowing the product quality prior to the harvest allows the manufacturer to take counter measures in case the forecasted quality or quantity deviates from what is expected. This would be a big step towards real‐time release, an important element of the FDA's PAT initiative. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1119–1127, 2015  相似文献   

12.
Due to a USAID-funded study on blood banks, a national policy was instituted in 1994 that set standards for Philippine blood services, promoted voluntary donation, and led to a ban on commercial blood banks. In this follow-up study, we assess the safety of the supply by determining the residual risk for transfusion-transmitted infections (syphilis, hepatitis B and C, HIV). We also identified unsafe facility practices and generated policy recommendations. A 1992 study found that transfusion-ready blood was not safe using the LQAS method (P > 0.05). We found that the 2012 residual risk became 0 to 0.9 percent attributable to the national policy. We noted poor to fair adherence to this policy. We identified unsafe practices such as use of rapid tests and lack of random blood retesting. Training and use of regional networks may improve safety. Despite improvement in safety, facilities complain of funding and logistical issues regarding compliance with the policy.  相似文献   

13.
Vinnikov V  Lloyd D  Finnon P 《Mutation research》2012,731(1-2):107-116
Following exposure to high doses of ionizing radiation, due to an accident or during radiotherapy, bystander signalling poses a potential hazard to unirradiated cells and tissues. This process can be mediated by factors circulating in blood plasma. Thus, we assessed the ability of plasma taken from in vitro irradiated human blood to produce a direct cytotoxic effect, by inducing apoptosis in primary human peripheral blood mononuclear cells (PBM), which mainly comprised G(0)-stage lymphocytes. Plasma was collected from healthy donors' blood irradiated in vitro to 0-40Gy acute γ-rays. Reporter PBM were separated from unirradiated blood with Histopaque and held in medium with the test plasma for 24h at 37°C. Additionally, plasma from in vitro irradiated and unirradiated blood was tested against PBM collected from blood given 4Gy. Apoptosis in reporter PBM was measured by the Annexin V test using flow cytometry. Plasma collected from unirradiated and irradiated blood did not produce any apoptotic response above the control level in unirradiated reporter PBM. Surprisingly, plasma from irradiated blood caused a dose-dependent reduction of apoptosis in irradiated reporter PBM. The yields of radiation-induced cell death in irradiated reporter PBM (after subtracting the respective values in unirradiated reporter PBM) were 22.2±1.8% in plasma-free cultures, 21.6±1.1% in cultures treated with plasma from unirradiated blood, 20.2±1.4% in cultures with plasma from blood given 2-4Gy and 16.7±3.2% in cultures with plasma from blood given 6-10Gy. These results suggested that irradiated blood plasma did not cause a radiation-induced bystander cell-killing effect. Instead, a reduction of apoptosis in irradiated reporter cells cultured with irradiated blood plasma has implications concerning oncogenic risk from mutated cells surviving after high dose in vivo irradiation (e.g. radiotherapy) and requires further study.  相似文献   

14.
Platelet-activating factor (PAF) is a potent phospholipid mediator that may participate in inflammatory responses by virtue of its ability to activate platelets, leukocytes, and vascular cells. We examined the synthesis and release of PAF by human peripheral blood monocytes (PBM) isolated by countercurrent elutriation. PAF was produced after stimulation by calcium ionophore A23187 (IoA), opsonized zymosan (OpsZ), and PMA with a relative order of potency IoA much greater than OpsZ greater than PMA. The portion of PAF subsequently released from the cell was dependent on the specific agonist, the time of incubation, and the presence of albumin. Under optimal conditions, PBM released 67, 49 and 32% of the total PAF produced in response to IoA, OpsZ, and PMA, respectively. Changes in PAF metabolism were observed in PBM that were examined after short term adherence or differentiation into macrophages. Adherent PBM accumulated and released less PAF than suspended monocytes, and monocyte-derived macrophages produced less PAF than the parent PBM. The ability of monocytes to release significant amounts of newly synthesized PAF from the cell is unusual among human cell types, which in general retain the vast majority of the lipid, and may be of particular pathophysiologic importance.  相似文献   

15.
A new European legislation on herbal medicinal products (HMPs) was developed, in order to harmonise the use of HMPs in the 28 member states of the European Union, according to Directive 2004/24/EC which amended the basic legislation laid down in Directive 2001/83/EC. The objective of this legislation was to ensure the future existence of such products and to consider particular characteristics during the assessment of their quality, efficacy and safety, having defined two categories for herbal medicines: (a) well-established use HMPs, which can be granted a marketing authorisation; and (b) traditional herbal medicinal products which can be granted a registration based on their long-standing safe and efficient use. The Committee on Herbal Medicinal Products was established at the European Medicines Agency in 2004, in order mainly to provide community monographs and list entries on herbal substances and preparations. 120 monographs have been published since then, which offer a scientific and regulatory standard for their safety and efficacy, during their use as medicinal products. The HMPs can be placed in the market after quality, efficacy, and safety have been assessed according to the provisions of the legislation (Directive 2004/24/EC and Directive 2001/83/EC), with adequate labeling information to patients and health care professionals, distinguishing them from other product categories containing herbs like: foods, food supplements, medical devices and cosmetics.  相似文献   

16.
Peripheral blood monocytes (PBM) from AIDS patients have exhibited defects in some but not all of the immune functions yet tested. This study has examined the capacity of AIDS PBM to lyse tumor target cells as well as their ability to secrete TNF. Untreated PBM from AIDS patients were significantly cytotoxic to U937 target cells and responded to IFN-gamma pretreatment with augmented cytotoxicity. Both the spontaneous and IFN-gamma-stimulated cytotoxic activity was significantly (p less than 0.01) higher than that observed with normal PBM. The cytotoxic activity depended on the E:T ratio used and was higher in AIDS PBM at all ratios tested (10:1 to 40:1). Because TNF has been implicated in macrophage cell-mediated cytotoxicity, we examined whether the elevated cytotoxic activity of AIDS PBM was associated with an increase in TNF production. Supernatants from PBM cultured overnight with or without IFN-gamma were tested in a bioassay measuring cytotoxicity against U937 target cells as well as in an RIA specific for TNF. Supernatants derived from either unstimulated or IFN-gamma-treated AIDS PBM exhibited significantly higher levels of cytotoxicity than supernatants from normal macrophages. Both normal and AIDS PBM produced higher levels of cytotoxic factors in response to IFN-gamma. As determined by the RIA, AIDS PBM spontaneously released high levels of TNF whereas little TNF was produced by normal PBM. Treatment with IFN-gamma augmented the level of TNF production in both AIDS and normal PBM. These results demonstrate that PBM from AIDS patients have undergone in vivo activation as manifested by both cytotoxicity against tumor target cells and production of TNF. Target cell lysis by both AIDS PBM and their supernatants was inhibited by monoclonal anti-rTNF, suggesting that the increase in PBM cell-mediated cytotoxicity was caused by an increase in TNF production. The significance of these findings in the pathogenesis of the disease is discussed.  相似文献   

17.
Higher temperatures resulting from climate change have led to predictions that the duration of the breeding season of many temperate bird species may be changing. However, the extent to which breeding seasons can be altered will also depend on the degree of flexibility in processes occurring at other points in the annual cycle. In particular, plasticity in the timing of post‐breeding moult (PBM) could facilitate changes in the timing of key events throughout the annual cycle, but little is known about the level of within‐ and between‐species plasticity in PBM. As part of the British Trust for Ornithology (BTO) Ringing Scheme, many ringers routinely record moult scores of flight feathers, and these can be used to provide information on the annual progression of PBM for a range of species. Here we use ringing data to investigate patterns of PBM in 15 passerines, as well as data from the BTO Nest Record Scheme to relate these differences to the timing of breeding of these species across the UK. We find considerable variation in both the mean start (19 May–29 July) and duration (66–111 days) of PBM between species, but find no evidence that species starting PBM later in the season complete it any faster. However, there is considerable within‐species variation in PBM, particularly for multi‐brooded species; PBM starts later and is completed in less time when the duration of the breeding season (difference between first and last nests) is longer. This implies that a later end to breeding can be compensated for by faster PBM, and that advances in breeding could lead to earlier and slower PBM. Our findings suggest that adaptation of PBM in response to climate‐mediated changes in the timing and duration of the breeding season is possible. However, the requirement to complete PBM prior to migration or the onset of winter might constrain the extent to which breeding seasons can lengthen, especially for later nesting species.  相似文献   

18.
Activation of sodium/proton (Na+/H+) antiport activity has been shown to occur as an early event in mitogenesis. Because amiloride inhibits Na+/H+ antiport activity, it is hypothesized that mitogenesis may be inhibited by amiloride. In this work, we examined the effect of amiloride on DNA synthesis as measured by [3H]thymidine uptake and immunoglobulin (Ig) production as measured by an ELISA system in human peripheral blood mononuclear cells (PBM). Amiloride at 100 microM concentration inhibited irradiated Raji cell (*R)-activated and phytohemagglutinin-P (PHA-P)-stimulated DNA synthesis by 50 +/- 11% and 72 +/- 12%, respectively. IgG production was inhibited by 71% at 100 microM amiloride concentration in *R-activated PBM. This concentration of amiloride inhibited Na+/H+ antiport activity by 92%. Because amiloride is known to inhibit other pre-replicative cellular functions such as protein synthesis, we used an amiloride analogue, dimethylamiloride, which inhibited Na+/H+ antiport activity by 90% at a concentration of 1 microM without inhibition of PBM Ig or DNA synthesis. Furthermore, neither PHA-P nor *R-stimulated PBM demonstrated an intracellular alkalinization even after 6 hr of stimulation. Similarly, T cell-enriched or B cell-enriched populations did not show intracellular alkalinization after PHA-P or *R activation. Thus, it appears that Na+/H+ antiport activation is not an early event in PBM mitogenesis. The inhibition of mitogenesis by amiloride may be due to abrogation of premitotic events such as protein synthesis.  相似文献   

19.
Interleukin 2(IL-2) is known to stimulate the progression of activated T cells from G1 through the rest of the cell cycle. We have demonstrated that addition of purified recombinant human IL-2 (rIL-2) to fresh normal human peripheral blood mononuclear cells (PBM), which were IL-2 receptor (Tac) negative by FACS analysis, stimulated marked proliferation of the PBM. IL-2-induced proliferation was also observed with umbilical cord blood mononuclear cells. Monocyte depletion of PBM resulted in a marked reduction of rIL-2-induced proliferative response which could be restored by adding back autologous irradiated monocytes but not by interleukin 1. The T cells preincubated with rIL-2 showed a five to six times enhanced autologous mixed-lymphocyte reaction (AMLR) compared to controls. The rIL-2-induced proliferative response of PBM was inhibited in a concentration-dependent fashion by preincubation of PBM with an anti-HLA-DR framework monoclonal antibody. The proliferating cells were shown by two-color flow cytometric analysis to be primarily Leu-1+ and Leu-4+ T cells (both leu-3+ and Leu-2+ subsets); however, 6 to 19% of responding cells had surface markers for B cells or NK cells. The data demonstrate that rIL-2 can induce proliferation of "resting" human T cells. The phenomenon may be related to a monocyte-dependent AMLR which induces IL-2 receptors and IL-2 responsiveness in a subset of T cells.  相似文献   

20.
亚甲基蓝(methyleneblue,MB)与可见光结合最近在临床上被尝试用来灭活单袋血浆中的病毒,它具有高效,安全,简便,毒性很低等特点。可大大降低因输血造成的病毒病传播的可能性。亚甲基蓝作为光敏染料不可逆的插入病毒核酸,诱导断裂缺口产生,导致病毒功能和遗传结构基础破坏,作者同时观察了血浆中丙种免疫球蛋白在光化学处理前后的二级结构改变。通过傅立叶转换红外光谱分析结果显示,MB/光处理后的丙种免疫球蛋白在处理前后没有明显的结构改变,二级结构基本保持完整。  相似文献   

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