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1.
综述Hippospongia属海绵的化学成分及生物活性。该属海绵次生代谢产物丰富,富含萜类、长链脂肪族类及甾体类化合物,且具有独特的生物活性,包括抗肿瘤、对DNA聚合酶β和HIV逆转录酶抑制作用及冠状血管舒张等作用,具有广阔的开发应用前景。对该属海绵化合物类型进行分类归纳,并对其药理活性研究进行综述,为该属海绵进一步研究开发提供参考。  相似文献   

2.
目的对掘海绵属(Dysidea spp)海绵的化学成分及生物活性进行综述。方法通过检索国内外相关文献,归纳总结了该属海绵的研究情况。结果从该属海绵中已分离鉴定了300个化合物,主要为倍半萜醌类、萜类、甾醇类、溴代衍生物、二酮哌嗪类、多氯取代化合物等;这些化合物具有抗肿瘤、抗炎、抗真菌和抑制HIV-Ⅰ逆转录酶等多种生物活性。结论对掘海绵的化学成分和生物活性的进一步研究提供参考。  相似文献   

3.
目的对Acanthella属海绵的化学成分及其生物活性进行综述。方法通过综述国内外相关文献,归纳总结了该属海绵的研究概况。结果从该属海绵中已分离鉴定110个化合物,主要为含有异腈基、异硫氰酸酯和甲酰胺等含氮基团的倍半萜、二萜类化合物。这类化合物具有抗疟、抗虫、抗污损、抗肿瘤、抗菌等多样的生物活性。结论为Acanthella属海绵的化学成分及生物活性的进一步研究提供依据。  相似文献   

4.
海绵是目前海洋天然产物研究中最吸引人的海洋生物之一,海绵中含有丰富的、结构新颖的次生代谢产物,大多数具有显著的生理活性。Phakellia属海绵属于寻常海绵纲软海绵目小轴海绵科,种类较多,分布广泛,在国内外得到了广泛的研究。对近几十年来从Phakellia属海绵中分离鉴定的次生代谢产物进行了系统的归纳整理,这些化学成分主要包括环肽、生物碱、聚醚、萜类、甾醇、炔酸等种类,并对其药理活性进行了简单总结,对Phakellia属海绵的进一步研究开发具有一定的借鉴和指导意义。  相似文献   

5.
系统综述了海绵Axinella属的生物碱、三萜、甾体等化学成分,及其抗肿瘤、抗菌、神经保护等生物活性的研究进展,为该属海绵的深入研究提供有用资料。  相似文献   

6.
Phyllospongia属海绵分布较为广泛,其次级代谢产物结构新颖多样,而且活性显著。从该属海绵中发现的次级代谢产物结构类型包括二倍半萜、呋喃萜、溴二苯醚、甾体、磺酸、核苷等类型化合物。其中,二倍半萜类化合物是该属海绵中最为典型的次级代谢产物,而且大多具有较强的生物活性,如细胞毒、抗菌、抗病毒、鱼毒、防附着等,在海绵的化学防御中发挥着重要作用。已有研究对从该属海绵乃至其他海绵中发现活性天然产物及药物先导化合物具有借鉴意义,文中对Phyllospongia属海绵中次级代谢产物的结构及其生物活性进行了简要综述。  相似文献   

7.
Dactylospongia属海绵中已报道的次生代谢产物主要包括倍半萜醌和倍半萜氢醌类、倍半萜衍生物、大环内酯及甾醇等结构类型,大多具有良好的生物活性,包括抗肿瘤、抗炎及抗菌等。本文根据化合物的结构类型综述了1989-2014年之间经文献报道的Dactylospongia属海绵的化学成分和生物活性,为该属海绵的进一步研究开发提供了参考。  相似文献   

8.
目的 对Agelas 属海绵化学成分和生物活性进行研究总结。方法 通过文献调研,对该属海绵代谢产物类型进行分类整理,并对其生物活性进行总结报道。结果 目前报道的Agelas 属海绵主要含有溴吡咯生物碱、萜类生物碱、鞘糖脂、甾醇、类胡萝卜素和脂肪酸等类型的代谢产物,许多具有良好的生物活性,包括抗肿瘤、抗疟、抗微生物、抗组织胺及免疫调节等活性。结论 Agelas属海绵次生代谢产物丰富,类型多样,并具有良好的生物活性,因此有广阔的开发应用前景。本文为该属海绵的进一步化学与生物活性研究开发提供参考。  相似文献   

9.
目的 对广西涠洲岛北部湾海域来源的锉海绵属(Xestospongia)海绵中获得的结构新颖、活性良好的甾体类成分进行研究。方法 根据甾体类化合物的结构特性,利用多种柱色谱和高效液相色谱(HPLC)等方法,通过高分辨质谱(HRMS)、核磁共振(NMR)和旋光(ORD)等方法并结合文献对照对化合物进行结构鉴定。结果 从锉海绵属海绵中分离得到9个甾体化合物,分别为7-ketocholesterol (1)、3β-Hydroxy-24-methylene-5-cholesten-7-one (2)、(22E)-3β-Hydroxychoiesta-5,22-dien-7-one (3)、(22E)-3β-Hydroxychiest-5,22-diene-7,24-dione (4)、Dictyopterisin G (5)、Dictyopterisins D (6)、Dictyopterisins E (7)、antrocarine E (8)和Fucosterol (9)。结论 化合物2-8均为首次从该属海绵中分离得到,6和7母核上C-7位为少见的甲氧基,8是首次从海绵中分离得到5-OH和7羰基的甾体化合物。  相似文献   

10.
海绵是目前海洋天然产物研究中最吸引人的海洋生物之一,海绵中含有丰富的、结构新颖的次生代谢产物,大多数具有显著的生理活性。Phakellia属海绵属于寻常海绵纲软海绵目小轴海绵科,种类较多,分布广泛,在国内外得到了广泛的研究。对近几十年来从Phakellia属海绵中分离鉴定的次生代谢产物进行了系统的归纳整理,这些化学成分主要包括环肽、生物碱、聚醚、萜类、甾醇、炔酸等种类,并对其药理活性进行了简单总结,对Phakellia属海绵的进一步研究开发具有一定的借鉴和指导意义。  相似文献   

11.
目的对中国南海海域细薄星芒海绵的三萜成分进行研究。方法采用硅胶柱色谱、Sephadex LH-20凝胶色谱、ODS C18柱色谱、半制备型HPLC等方法进行分离,根据理化性质和波谱分析鉴定化合物的结构。结果分离并鉴定了5个异玛拉巴烷型三萜化合物,分别为stelletinA(Ⅰ),stelletin B(Ⅱ),22,23-dihydrostelletin D(Ⅲ),jaspolide B(Ⅳ)和jaspolide A(Ⅴ)。结论化合物Ⅲ~Ⅴ首次从该种海绵中获得。  相似文献   

12.
目的研究细薄星芒海绵Stelletta tenuisLindgren的抗肿瘤活性成分。方法利用溶酶萃取和多种层析手段,以体外细胞毒模型跟踪筛选,对南海细薄星芒海绵的抗肿瘤活性成分进行追踪分离,应用波谱技术,并结合文献对照,对所分离得到的化合物进行结构鉴定。结果得到8个异玛拉巴烷(isomalabaricane)型三萜类化合物,其结构分别鉴定为:stellettin B(1),C(2),D(3),E(4),rhabdastrellic acid A(5),stellettin H(6),22,23-dihydrostellettin B(7),geoditin A(8)。结论化合物1-8均系首次从中国南海海绵Stelletta ten-uisLindgren中获得,并归属了它们的1H NMR和13C NMR数据。  相似文献   

13.
Internal and external carotid vascular resistances were measured, in anaesthetized monkeys, to asses the direct cranial vascular effects of i.v. methysergide, pizotifen and ergotamine, and their effects on the cranial vascular responses to the constrictors 5-hydroxytryptamine and noradrenaline and the dilators histamine, prostaglandin E1 and bradykinin. Methysergide reduced responses to 5-HT, and tended to potentiate the external carotid responses to noradrenaline. Pizotifen blocked responses to histamine; it tended to reduce internal carotid responses to 5-HT, but it potentiated external carotid 5-HT responses. Ergotamine reduced responses to 5-HT and noradrenaline, but this was probably related to its cranial vasoconstrictor effects, especially in the external carotid circulation. Methysergide induced weak transient cranial vasoconstriction and pizotifen had no direct effects. These findings may be relevant to the therapeutic actions of these drugs in migraine, since the doses used approximated to those used clinically.  相似文献   

14.
Metallothioneins (MTs) mediate resistance to metal and non-metal toxicants. To differentiate the role of MTs from other protective factors, resistance to zinc (Zn), cadmium (Cd), tertbutyl hydroperoxide (tBH), and cisplatin (CDDP) was compared in renal cell lines from wild type (MT-WT) and MT-1/MT-2 knockout (MT-KO) mice. MT-WT cells were more resistant to tBH than MT-KO cells but, unexpectedly, were more sensitive to Zn, Cd, and CDDP. Thus, basal expression of MT conferred resistance to tBH, but not to Cd or CDDP. Pretreatment with Zn increased MT expression and enhanced resistance to Cd and CDDP only in MT-WT cells, indicating a critical role for MT in this form of resistance. By contrast, Zn-pretreatment increased resistance to subsequent Zn exposure, but did not alter resistance to tBH, regardless of MT-status. Therefore, Zn-induced resistance to subsequent exposure to Zn (but not to Cd or CDDP) was mediated by non-MT factors, and neither Zn-induced MT nor other factors affected tBH sensitivity. Furthermore, antisense down-regulation of MT in human HeLa cells reduced basal MT levels and resistance to TBH, but not to Cd or CDDP. Therefore, basal MT alone can mediate resistance to TBH (but not to Cd or CDDP) in mouse and human cells. These data suggest that MT can mediate resistance to toxicants by different mechanisms, some of which correlate with the cellular content of MT protein. Moreover, resistance to some agents (Cd and CDDP) can be enhanced by inducing MT. Resistance to other agents (tBH) requires only basal (non-induced) MT levels.  相似文献   

15.
Objective A lack of skilled health professionals, and net migration from developing to more developed countries, are widely recognised as barriers to the delivery of effective health care. However, few studies have investigated this issue from the perspective of pharmacists, although they are increasingly viewed as a potentially valuable and underexploited health care resource. The objectives of this study were to examine the professional aspirations and perceived opportunities of final year pharmacy students in a developing country; and consider what developments may encourage them to remain in, and contribute to, health care in their home country. Method Final year pharmacy students from the Faculty of Pharmacy, KNUST, Kumasi, Ghana, were randomly selected and invited to participate in in-depth interviews. These were audio-recorded (with permission of respondents) and transcribed verbatim to enable a qualitative analysis. Main outcome measure: professional aspirations, and perceived opportunities and barriers to their achievement in Ghana and abroad. Results Participants viewed themselves, and wished to be viewed by others, as health professionals. They described a commitment to applying their clinical knowledge and to education beyond their first degree. However, they identified significant barriers to the achievement of professional aspirations in Ghana, which would diminish their opportunities to contribute to health care. Whilst most students expressed the expectation or desire to travel at some point, usually early, in their career, they all demonstrated a commitment to their country and stated a wish to return. Conclusion Overall the study highlighted prospective pharmacists in Ghana as ambitious, committed potential health professionals. The study indicates that a lack of attention by policy makers and professional bodies to ways of exploiting the contribution of pharmacists to public health, may represent a lost potential human resource for health in developing countries.  相似文献   

16.
17.
A multicompartment biologically based dynamic model was developed to describe the time evolution of methanol and its metabolites in the whole body and in accessible biological matrices of rats, monkeys, and humans following different exposure scenarios. The dynamic of intercompartment exchanges was described mathematically by a mass balance differential equation system. The model's conceptual and functional representation was the same for rats, monkeys, and humans, but relevant published data specific to the species of interest served to determine the critical parameters of the kinetics. Simulations provided a close approximation to kinetic data available in the published literature. The average pulmonary absorption fraction of methanol was estimated to be 0.60 in rats, 0.69 in monkeys, and 0.58-0.82 in human volunteers. The corresponding average elimination half-life of absorbed methanol through metabolism to formaldehyde was estimated to be 1.3, 0.7-3.2, and 1.7 h. Saturation of methanol metabolism appeared to occur at a lower exposure in rats than in monkeys and humans. Also, the main species difference in the kinetics was attributed to a metabolism rate constant of whole body formaldehyde to formate estimated to be twice as high in rats as in monkeys. Inversely, in monkeys and in humans, a larger fraction of body burden of formaldehyde is rapidly transferred to a long-term component. The latter represents the formaldehyde that (directly or after oxidation to formate) binds to various endogenous molecules or is taken up by the tetrahydrofolic-acid-dependent one-carbon pathway to become the building block of synthetic pathways. This model can be used to quantitatively relate methanol or its metabolites in biological matrices to the absorbed dose and tissue burden at any point in time in rats, monkeys, and humans for different exposures, thus reducing uncertainties in the dose-response relationship, and animal-to-human and exposure scenario comparisons. The model, adapted to kinetic data in human volunteers exposed acutely to methanol vapors, predicts that 8-h inhalation exposures ranging from 500 to 2000 ppm, without physical activities, are needed to increase concentrations of blood formate and urinary formic acid above mean background values reported by various authors (4.9-10.3 and 6.3-13 mg/liter, respectively). This leaves blood and urinary methanol concentrations as the most sensitive biomarkers of absorbed methanol.  相似文献   

18.
Disseminating research findings from global health collaborations is essential to advancing science. However, there are a number of ethical considerations and potential challenges to address to ensure thoughtful and non-exploitative reporting. The factors include the benefits and risks to publication, authorship criteria or values, and the accessibility of forums or journals in which to pursue publication. This paper provides commentary related to planning for writing, communicating intentions to publish, obtaining permissions to publish, risks in internationally collaborative work, authorship principles, and journal selection. Authors' and editors’ knowledge of experienced individuals from both pharmacy literature, medical fields, and general publications is incorporated to provide an assessment of risks and benefits of publication of international global health research.  相似文献   

19.
Medical and medication errors remain definite threats to patients in US health care. Medical toxicologists frequently encounter patients either harmed by or at risk for harm from adverse drug events, including medication errors and inadvertent exposures. An historical perspective, as viewed through the lens of specific disciplines, can be useful to trace systemic responses to safety threats. Early efforts to address anesthesia perioperative risks and recent actions in medicine, surgery, and obstetrics to introduce checklists, communication tools, and systems approaches are reviewed. Patient safety concepts can be utilized and disseminated by toxicologists to improve medication safety and drive innovative approaches to confront patient harm. Various approaches include simulation of high-risk scenarios which might predispose to medication error, assembling multidisciplinary groups of health care providers to review events and implement mitigation strategies, and proactive patient safety rounds in clinical areas to allow frontline staff to voice concerns and introduce solutions for administration, evaluation, and implementation. We review selected lessons from the past and current innovations to achieve safe medication practice.  相似文献   

20.
ABSTRACT

The contamination legacy of industrialization, militarization, and nuclear arms race poses current or future risks to populations and the environment. Responsible parties and regulators make decisions regarding which sites to clean up, how, how much, and when. This study aimed to provide an information needs template to evaluate and reduce risks to human health when considering whether to initiate or delay remediation. This investigation focused on four aspects of timing and prioritization: 1) management, planning and implementation, 2) source terms, pathways, and exposures, 3) risks and receptors, and 4) external drivers. Within each type, issues were identified and described. Management class included personnel, health and safety data, funding, equipment, and structural integrity. Source term included contaminant sources, pathways, initiating events, and barriers to exposure. Risk included types and exposures to workers and general public. External drivers included regulatory framework, stakeholders, Congressional mandates, and economic and social contexts. Risk may increase over time as contamination spreads, enters aquifers, and reaches receptors, and may decline as radionuclides decay, and plumes dissipate. The overall objective was to provide a template of information that is useful to managers and regulators, and might be used by the public to understand the risks and benefits of re-prioritization cleanup.  相似文献   

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