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Objectives: Curcumin, a natural compound, is a potent anti‐cancer agent, which inhibits cell division and/or induces cell death. It is believed that normal cells are less sensitive to curcumin than malignant cells; however, the mechanism(s) responsible for curcumin’s effect on normal cells are poorly understood. The aim of this study was to verify the hypothesis that curcumin affects normal cell division by influencing microtubule stability, using mouse oocyte and early embryo model systems. Materials and methods: Maturating mouse oocytes and two‐cell embryos were treated with different concentrations of curcumin (10–50 μm), and meiotic resumption and mitotic cleavage were analysed. Spindle and chromatin structure were visualized using confocal microscopy. In addition, acetylation and in vitro polymerization of tubulin, in the presence of curcumin, were investigated and the damage to double‐stranded DNA was studied using γH2A.X. CDK1 activity was measured. Results and conclusions: We have shown for the first time, that curcumin, in a dose‐dependent manner, delays and partially inhibits meiotic resumption of oocytes and inhibits meiotic and mitotic divisions by causing disruption of spindle structure and does not induce DNA damage. Our analysis indicated that curcumin affects CDK1 kinase activity but does not directly affect microtubule polymerization and tubulin acetylation. As our study showed that curcumin impairs generative and somatic cell division, its future clinical use or of its derivatives with improved bioavailability after oral administration, should take into consideration the possibility of extensive side‐effects on normal cells.

Peri-implantation porcine embryos express interleukin-1β (IL-1β), which could affect uterine activity during early pregnancy. In vitro studies were conducted to determine if IL-1β stimulates secretion of PGE₂ and expression of cyclooxygenase-2 (COX-2) mRNA and microsomal PGE synthase-1 (mPGES-1) mRNA in uterine tissues harvested from pigs on days 10 to 11, 12 to 13 and 15 to 16 of pregnancy and the estrous cycle. IL-1β (10 ng/ml) increased PGE₂ secretion and mPGES-1 mRNA expression in uterine tissues isolated from pigs between days 10 to 13 of pregnancy and the estrous cycle. IL-1β stimulated PGE₂ and mPGES-1 mRNA expression only in cyclic uterine tissues on days 15 to 16. Interleukin-1β increased COX-2 mRNA expression in the endometrial tissues of pregnant and cyclic pigs harvested on days 10 to 13. It stimulated COX-2 expression in pregnant pigs' myometrial tissues on days 10 to 11, and on days 15 to 16 in tissues from both pregnant and cyclic pigs. The uterine secretion of PGE₂ in response to IL-1β was determined by local intrauterine concentrations of P₄ and E₂. This study demonstrates that IL-1β activates expression of mPGES-1 mRNA in uterine tissues to stimulate synthesis and secretion of PGE₂ on days 10 to 13 of both pregnancy and the estrous cycle. The profile of COX-2 mRNA expression in the myometrium differs from its profile in the endometrium. This work provides new insight on the role of IL-1β in PGE₂ production to overcome luteolysis in pregnant pigs.

Background The mammalian forkhead box, class O (FoxO) transcription factors function to regulate diverse physiological processes. Emerging evidence that both brain-derived neurotrophic factor (BDNF) and lithium suppress FoxO activity suggests a potential role of FoxOs in regulating mood-relevant behavior. Here, we investigated whether brain FoxO1 and FoxO3a can be regulated by serotonin and antidepressant treatment and whether their genetic deletion affects behaviors. Methods C57BL/6 mice were treated with d-fenfluramine to increase brain serotonergic activity or with the antidepressant imipramine. The functional status of brain FoxO1 and FoxO3a was audited by immunoblot analysis for phosphorylation and subcellular localization. The behavioral manifestations in FoxO1- and FoxO3a-deficient mice were assessed via the Elevated Plus Maze Test, Forced Swim Test, Tail Suspension Test, and Open Field Test. Results Increasing serotonergic activity by d-fenfluramine strongly increased phosphorylation of FoxO1 and FoxO3a in several brain regions and reduced nuclear FoxO1 and FoxO3a. The effect of d-fenfluramine was mediated by the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Chronic, but not acute, treatment with the antidepressant imipramine also increased the phosphorylation of brain FoxO1 and FoxO3a. When FoxO1 was selectively deleted from brain, mice displayed reduced anxiety. In contrast, FoxO3a-deficient mice presented with a significant antidepressant-like behavior. Conclusions FoxOs may be a transcriptional target for anxiety and mood disorder treatment. Despite their physical and functional relatedness, FoxO1 and FoxO3a influence distinct behavioral processes linked to anxiety and depression. Findings in this study reveal important new roles of FoxOs in brain and provide a molecular framework for further investigation of how FoxOs may govern mood and anxiety disorders.

The mobile payment services markets are currently under transition with a history of numerous tried and failed solutions, and a future of promising but yet uncertain possibilities with potential new technology innovations. At this point of the development, we take a look at the current state of the mobile payment services market from a literature review perspective. We review prior literature on mobile payments, analyze the various factors that impact mobile payment services markets, and suggest directions for future research in this still emerging field. To facilitate the analysis of literature, we propose a framework of four contingency and five competitive force factors, and organize the mobile payment research under the proposed framework. Consumer perspective of mobile payments as well as technical security and trust are best covered by contemporary research. The impacts of social and cultural factors on mobile payments, as well as comparisons between mobile and traditional payment services are entirely uninvestigated issues. Most of the factors outlined by the framework have been addressed by exploratory and early phase studies. © 2007 Elsevier B.V. All rights reserved.

Fieldwork has long been identified as providing students undertaking professional studies with a means of implementing theory into a real world context. In recent years some educators, particularly in the health sciences, have introduced mobile devices to support students' fieldwork learning. In many ways there is a natural link between fieldwork and mobile technology. In this paper we report on a trial to introduce mobile support into the study of information systems in the field. The experience showed that mobile devices can assist students collect data in richer, multimedia formats and make subsequent classroom presentations of their field study much more interesting. However, it also revealed certain usage and deployment issues with the mobile devices themselves which have implications for device selection and educational design. © 2008 Crown Copyright.

This paper aims to inform readers of suggested directions for researching how mobile technology can enhance active student learning. These directions are informed by an online survey of our students in early 2007 and a contemporary literature search. We present the findings of our search of global best-practice in m-learning, gaps in the current literature are identified and five directions are suggested for 2007 m-learning research and development. We start discussing how to investigate these suggested directions. Our five suggested action research directions are all significant issues in m-learning and all need to be better investigated. If we are interested in enhancing student learning, a priority is to design mlearning and teaching strategies that involve active experiential learning. These strategies need to effectively support our learners' development of attitudes, understandings and skills in identified graduate attributes, curriculum objectives and stated learning outcomes. The development of wide support for an online body of knowledge of m-learning and teaching principles, strategies and effective, practical case-studies across all disciplines - an m-portal - is needed and can support and inform emerging national and international approaches to using mobile technologies to enhance learning. Guided by our findings and suggested research suggestions the authors hope to discuss, extend and develop collaborative partnerships for future action research, development and sponsorship at our ascilite 2007 conference workshop. © 2007 Andrew Litchfield, Laurel Evelyn Dyson, Elaine Lawrence and Agnieszka Zmijewska.

Akt is a serine/threonine protein kinase that plays a vital role in promoting cellular survival. Predominantly cytosolic, upon stimulation with growth-factors or stress, active Akt translocates into mitochondria, but the functions of Akt in mitochondria are not yet fully understood. Mitochondria play a central role in apoptotic pathways and given Akt's functions in the cytoplasm, Akt in mitochondria may help preserve mitochondrial integrity during cellular stress. To test if the translocation of Akt into mitochondria is neuroprotective, adenoviral vectors expressing a constitutively active Akt, Ad-HA-Akt (DD), and a constitutively active Akt with a mitochondrial targeting signal, Ad-Mito-HA-Akt (DD), were generated. Human SH-SY5Y neuroblastoma cells expressing the adenoviral constructs were treated with staurosporine to initiate intrinsic apoptotic cell death and several aspects of the mitochondrial apoptotic pathway were evaluated. Expression of active Akt targeted to mitochondria was found to be sufficient to significantly reduce staurosporine-induced activation of caspase-3 and caspase-9, the release of cytochrome c from mitochondria, and Bax oligomerization at mitochondria. These findings demonstrate that intramitochondrial active Akt results in efficient protection against apoptotic signaling.

Mobile payment hype posits that Mobile Commerce will deliver e-commerce services directly into the consumers' hands - anytime, anywhere - using wireless technologies. However our research has indicated that in the short term at least these services will likely be low value and various mobile payment initiatives have failed or will fail. Applying mobile access to computing creates both tremendous commercial opportunities and complexity, yet will make computing globally pervasive and ubiquitous. Providing such services is fraught with problems such as legal and security issues as well as the need to track payments whilst the consumer is on the move and the mobile device may drop out. Customers prefer a choice in the channels through which they do business and the same applies to mobile payments as well. The research questions are: Is it necessary to partner to achieve success in the mobile payment area? Is it a case of partner or perish? This paper reports on three Australian Case studies to explore the current state of mobile financial transactions and illustrates the difficulties faced by both mobile payment enablers and 10090 consumers.

University of Technology, Sydney. Faculty of Information Technology. Mobile devices have a potential to become ideal payment devices because they are small, light, personal, convenient, and many people carry them anytime, anywhere. Mobile devices have a number of connectivity options, and their own display and input capabilities. They are already widely used around the world. Mobile payments, despite their potential, have not reached the expected adoption levels. While there may be many reasons for this, previous research focused on few topics only, mainly technology and consumers. The main aim of this study was to find out what is necessary to improve adoption and diffusion of mobile payments. Specific objectives that were proposed to help achieve this aim included: a) identifying all the factors that may influence adoption and diffusion of mobile payments, b) integrating such factors and relations between them in a holistic framework, and c) providing specific recommendations and guidelines in all the various perspectives. Grounded theory was the methodology employed to fulfil these objectives. Qualitative approach was found to be most suitable to this study, and open- ended Web surveys, as well as various kinds of interviews, including email, face-to-face, phone, and focus groups managed to obtain detailed, in-depth information from industry and user participants. The main contribution of this study is the holistic theoretical framework that explains the specific factors that influence adoption and diffusion of mobile payments, provides interesting findings on each of the identified factors, and at the same time integrates such investigations together as one coherent whole that forms a roadmap of success factors for mobile payments. Some of the discovered factors have not been proposed before at all. Some others have been proposed in fragmented explanations that focused on several influences only. Other factors have been proposed before but this study offered more accurate or understandable interpretations or names for them. In addition, this project integrated all the factors together in a holistic framework, pointing out all the important contexts and conditions that providers need to understand and fulfil. Another contribution is a multitude of specific guidelines and recommendations that have been discovered in the participants' data. This study, unlike some other mobile payment projects, additionally devoted much attention to studying mobile payments in relation to other payment methods. The proposed theory with its well explained success factors can be used by providers to improve their current systems or better design new mobile payment initiatives.

This study concentrates on investigating the degree of awareness, future adoption and uptake of wireless sensor networks (WSNs) (in particular Motes) in the Health Monitoring arena via the use of our second Web-based survey. The Unified Theory of Acceptance and Use of Technology (UTAUT) has been applied to determine how viable this technology will be for health monitoring in healthcare institutions and patients' homes. Results from our study show positive support for the acceptance of the technology yet reveal some real concerns about the issues of security, privacy, ethics and safety.

Deficient signaling by insulin, as occurs in diabetes, is associated with impaired brain function, and diabetes is associated with an increased prevalence of Alzheimer’s disease. One of the hallmark pathological characteristics of Alzheimer’s disease is the presence of neurofibrillary tangles containing hyperphosphorylated tau, a microtubule-associated protein. Therefore, we tested the hypothesis that insulin depletion caused by administration of streptozotocin may cause tau hyperphosphorylation in mouse brain by using site-specific phosphorylation-dependent tau antibodies to obtain precise identification of the phosphorylation of tau on individual residues. A massive (fivefold average increase) and widespread at multiple residues (detected with eight different phosphorylation-dependent tau antibodies) increase in the phosphorylation of tau was found in mouse cerebral cortex and hippocampus within 3 days of insulin depletion by streptozotocin treatment. This hyperphosphorylation of tau at some sites was rapidly reversible by peripheral insulin administration. Examination of several kinases that phosphorylate tau indicated that they were unlikely to account for the widespread hyperphosphorylation of tau caused by streptozotocin treatment, but there was a large decrease in mouse brain protein phosphatase 2A activity, which is known to mediate tau phosphorylation. These results show that insulin deficiency causes rapid and large increases in tau phosphorylation, a condition that could prime tau for the neuropathology of Alzheimer’s disease, thereby contributing to the increased susceptibility to Alzheimer’s disease caused by diabetes.

Typography is increasingly undertaken with and mediated through Information Technologies. One of the most visible manifestations of this change is the expansion from the printed page to screen environments and device displays. Moving type is an example of a new quality of text made possible by the use of new technologies. In this study we propose a framework that can help answer questions such as why type should move at all, what benefits moving type can offer, and how it can be best used to enhance the visual display of text. The framework categorises the uses of moving type, based on whether the movement of text enhances reading, viewing or using of a text, or a combination of the above. The categories are illustrated with examples of existing moving type works, which provided a basis for discussion of various challenges and issues specific to each category.

IL-6 is a biologically active substance and is thought to contribute to the development of obesity. Recent findings suggest that susceptibility to intracellular lipid accumulation is to a large extent determined by changes in the expression of fatty acid transporters such as FAT/CD36, FABPpm and FATP-1. The aim of the present study was to determine the effect of IL-6 deficiency on the expression of fatty acid transporters, as well as, assess the concomitant changes in intracellular lipids. We found that Il-6 deficiency upregulated the myocardial expression of FAT/CD36 (+40%) and did not significantly affect the content of FABPpm and FATP-1 (+15% and +5% respectively). Although no change in the intramyocardial total lipid content was noted, there was a significant increase in the intracellular content of both free fatty acid (FFA), diacylglicerol (DG) and ceramide fractions (+45%, +37% and +48%, respectively) in hearts from IL-6 -/- mice. A trend for IL-6 deficiency to increase in saturated FA species in these fractions was also observed (+8%, +12% and +10%, respectively). In contrast, IL-6 deficiency has no effect on the content of monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) species in each intramyocardial lipid fractions examined. These findings suggest that IL-6 deficiency results in 1) upregulation of myocardial content of FAT/CD36, 2) the increase in the content of biologically active lipid pools (FFA, DG and ceramide). This lipid accumulation with concomitant trend for increase in the saturation status of these lipid fractions may, at least in part, provide a factor related to the development of intramyocardial lipotoxicity, observed in obese individuals.

Motes which are tiny, wireless sensor devices (Smart Dust) have the potential for transforming the biomedical and healthcare industry sector. Researchers consider motes as prototypes for nano-devices (built from off-the-shelf technology also known as commodity based hardware), which will become a reality in 10 years time. The bio-medical and healthcare market is among the fastest growing markets for WiFi and other Wireless LAN Technologies. Motes are being trialed for emergency triaging, patient profiling and monitoring and education. This paper reports on the findings of a second anonymous web survey of over 100 participants from Australia, Europe and North America, aimed at investigating the possible acceptance of Motes as a reliable and efficient health monitoring tool. An acceptance model, Unified Theory of Acceptance and Use of Technology (UTAUT) has been applied to determine how viable this technology will be in medical institutions and patients’ homes. This paper reports specifically on the subjective comments made by the survey participants in an effort to measure the acceptance or non-acceptance of motes for monitoring health.

Mobile Commerce promises to deliver e-commerce services directly into the consumers' hands - anytime, anywhere - using wireless technologies. Applying mobile access to computing creates both tremendous commercial opportunities and complexity, which will make computing globally pervasive and ubiquitous. Customers prefer a choice in the channels through which they do business and the same applies to transactions as well. This paper reports on a project which explored the current state of mobile financial transactions globally using Bluetooth as an enabling technology. © 2005 IEEE.

The aim of this paper is presentation of new methods of laser and surgery treatment for glaucomatous patients, mainly no perforating operations: deep sclerectomy and viscocanalostomy and new modifications of known very well trabeculectomy.

Mobile payments involve the use of a mobile device and one or more wireless technologies. As the field is at an early stage of development, there is still a lot of uncertainty about which of available wireless technologies will lead to the most successful solutions. Cellular networks, near field communication, infrared and Bluetooth are analysed in terms of their suitability for mobile payments. This paper tries to find out which of these technologies can lead to systems that the user will be most likely to accept. Acceptance factors discovered in the author's previous research are used in this analysis: perceived ease of use, usefulness, mobility, trust and cost. The study reveals which of the technologies are likely to best fulfil each of the acceptance criteria.

Glycogen synthase kinase-3 (GSK3), which is inhibited by serine-phosphorylation, is involved in the neuropathology of Alzheimer's disease (AD). We tested if the two therapeutic strategies used for AD, inhibition of acetylcholinesterase and of N-methyl-D-aspartate (NMDA) receptors, modulate the phosphorylation state of the two isoforms of GSK3 in mouse brain. Large, rapid increases in the levels of phospho-Ser21-GSK3alpha and phospho-Ser9-GSK3beta occurred in mouse hippocampus, cerebral cortex, and striatum after treatment of mice with the muscarinic agonist pilocarpine or the acetylcholinesterase inhibitor physostigmine. Treatment with memantine, an NMDA receptor antagonist, also increased the serine-phosphorylation of both GSK3 isoforms in mouse brain. Co-administration of physostigmine and memantine increased serine-phosphorylated GSK3 levels equally to that achieved by either agent alone, indicating that the actions of these two drugs converge on overlapping pools of GSK3. Thus, drugs in each class of therapeutic agents used for AD have the common property of increasing the regulatory serine-phosphorylation of GSK3 within common pools of the enzyme.

The aim of this study is to present the results of screening examinations of refractive errors, taken on 1002 of school children ranging from 6 to 15 years of age.As the result of Internet screening visual acuity and color perception tests named "I can see..." in 10,021 children from randomly chosen schools in Poland in the year 2002, the group of 1002 children was chosen. In this group, the subjective and objective refractive error examination was taken as well as the visual acuity test, color perception with the use of Ishihara tables and full ophthalmologic examination.Average visual acuity was RE: 0.72 (SD +/- 0.31) and LE: 0.72 (SD +/- 0.31). The prevalence of emmetropia was 34%. In the examined group myopia in 17%, hyperopia in 20%, astigmatism in 5.5% of children was found, and in 24.5% of patients complex errors occur such as myopic and hyperopic astigmatism.

Activation of muscarinic receptors has been shown to be neuroprotective in several different models of apoptosis, but the mechanism of this action is unknown. Therefore, we investigated the intermediate signals mediating the anti-apoptotic action of muscarinic receptor activation in SH-SY5Y cells. Inhibition of most muscarinic receptor-coupled actions had no effect on protection, but inhibition of Rho kinase with HA-1077 concentration-dependently was able to completely block the protection against H(2)O(2)- and camptothecin-induced apoptosis produced by stimulation of muscarinic receptors. These results demonstrate that the anti-apoptotic effect provided by muscarinic receptor stimulation is dependent on the activity of Rho kinase.

The influence of MMC on the cornea, especially on the corneal endothelium and thickness, were checked.In one-year-follow up patients after trabeculectomies with or without topical use of mitomycin C were controlled for early and late complications, and levels of intraocular pressure. The progression of glaucomatous neuropathy was obtained by comparing the cup to disc ratio and some parameters of static visual field testing (MD, PSD) progressions, after one year observations.Intraocular pressures were stable and at lower levels in the group of patients after primary trabeculectomies (group C) than in the control group (group A). We obtained good, statistically significant decrease in IOP in all groups during one year follow-up.We didn't find any toxic effects of MMC, given on a sponge during trabeculectomy, on the morphology and physiology of the corneal endothelium and the central corneal thickness. We also didn't note any differences between groups in the progression of glaucomatous optic nerve damaged and cataract after 1 year follow up.

The aim of this study was to retrospectively analyze intraocular pressure and state of the eyeball in patients treated with diode laser, and to compare the outcomes with a group of patients after cyclodiahtermy under the scleral flap. We analyzed: visual acuity, IOP, percentage of lowering the IOP from the beginning, subjective patients' feelings of pain and complications.TSCPC is safe for patients and may be repeated, if needed. Laser cyclodestruction gives new possibilities in noninvasive IOP lowering with less complications than cyclodiahtermy, without changes in patient's visual functions.

Different antiproliferative agents: 5-fluorouracil, mitomycin C, growth factors antibodies, cyclosporine A, used as an adjunct to improve the success rate in filtering surgery and most common complications associated with them, are described.

Glaucoma, if left untreated, leads to blindness, but if detected early, disease progression can be stopped or slowed with drugs or surgical treatment. The development of existing and new diagnostic methods has allowed substantial improvement in the clinical detection of possible glaucoma. But in some cases false positive diagnoses can be undertaken. In this paper we discussed reasons for the wrong evaluation of factors suggesting the diagnosis of glaucoma, with special interest for mistakes in applanation tonometry results caused by thick cornea.

Heat shock protein-90 (Hsp90) buffers cells from genetic mutations and environmental stresses. To test if this capability reflects a normal physiological function of Hsp90 to buffer cellular signals, the effects of Hsp90 inhibition were measured on activation of Akt. Inhibition of Hsp90 with geldanamycin amplified Akt phosphorylation induced by insulin-like growth factor-1 (IGF-1) or insulin, indicating that Hsp90 normally buffers these signals. Furthermore, with IGF-1 stimulation Hsp90 inhibition increased p38 activation, produced additive activation of p90RSK, and slightly increased the duration of ERK1/2 activation. Hsp90 dampened Akt signaling by facilitating phosphatase-mediated dephosphorylation of Akt. Thus, Hsp90 not only buffers the cellular effects of mutations and stresses, but also buffers the magnitude and duration of activation of proliferative and survival-promoting signaling responses.

Sections from the frontal part of the mandible of 43 human foetuses from 9 to 39 weeks of prenatal age, which contained two, three and sometimes four lower incisors were immunohistochemically examined using protein gene product and neuron specific enolase (NSE) antibodies in order to establish the time of appearance of nerve fibres in the developing tooth germ and to define their topography. Nerve fibres were first detected in the dental follicle in the 11th week of intrauterine life. Their presence in the dental papilla was confirmed in the 18th week when the first layers of dentine and enamel were deposited. In the 24th week of intrauterine life, the nerve fibres first reached the subodontoblastic region. In the subsequent weeks, an increase in the number of nerve fibres accompanying blood vessels in the central portion of the dental papilla resulted in the formation of neuro-vascular bundles. Moreover, the progressive deposition of enamel and dentine was accompanied by branching of papillary nerves, which thereby formed a fan-pattern. In the foetal period, no evidence was found for the formation of a subodontoblastic plexus. However, we did observe single nerve fibres in close proximity to the odontoblast layer at the end of intrauterine life. Nerve fibres were not detected in either predentine or dentine throughout foetal life.

To establish the efficacy and safety of timolol maleate/dorzolamide fixed combination (TDFC) versus timolol maleate/pilocarpine fixed combination (TPFC), each given twice daily, in primary open-angle glaucoma or ocular hypertensive patients.In this prospective, multicentred, double-masked trial, 37 patients were treated twice daily with timolol for 4 weeks. They were then randomized to one of the treatment medications for 6 weeks, after which they were treated with timolol again for 2 weeks before being placed on the opposite treatment medication for 6 weeks.A total of 36 patients completed the trial. Their mean baseline intraocular pressure (IOP) was 22.3 +/- 3.7 mmHg. Following 6 weeks of treatment, the mean trough (08.00 hours) IOP was 18.0 +/- 2.2 mmHg for TDFC and 17.4 +/- 2.0 mmHg for TPFC (p = 0.22). The mean diurnal curve IOP was 18.1 +/- 2.2 mmHg for TDFC and 16.7 +/- 1.9 mmHg for TPFC (p = 0.0007). At the remaining time-points (10.00, 18.00 and 20.00 hours), TPFC IOPs were statistically lower than TDFC IOPs (p0.03). There were statistically more unsolicited reports of vision change and ocular pain associated with TPFC (p = 0.04). Six patients were discontinued early from TPFC therapy (17%) versus two from TDFC (6%) (p = 0.13).This study suggests that TPFC can provide at least a similar efficacious reduction in IOP as TDFC in patients with primary open-angle glaucoma or ocular hypertension.

The impact of muscarinic receptor stimulation was examined on apoptotic signaling induced by DNA damage, oxidative stress, and mitochondrial impairment. Exposure of human neuroblastoma SH-SY5Y cells to the DNA-damaging agent camptothecin increased p53 levels, activated caspase-3, and caused cell death. Pretreatment with oxotremorine-M, a selective agonist of muscarinic receptors that are expressed endogenously in these cells, did not affect the accumulation of p53 but greatly attenuated caspase-3 activation and protected from cell death to nearly the same extent as treatment with a general caspase inhibitor. Treatment with 50-200 microm H(2)O(2) caused the activation of caspase-3 beginning after 2-3 h, followed by eventual cell death. Oxotremorine-M pretreatment protected cells from H(2)O(2)-induced caspase-3 activation and death, and this was equivalent to protection afforded by a caspase inhibitor. Muscarinic receptor stimulation also protected cells from caspase-3 activation induced by exposure to rotenone, a mitochondrial complex 1 inhibitor, but no protection was evident from staurosporine-induced caspase-3 activation. The mechanism of protection afforded by muscarinic receptor activation from camptothecin-induced apoptotic signaling involved blockade of mitochondrial cytochrome c release associated with a bolstering of mitochondrial bcl-2 levels and blockade of the translocation of Bax to mitochondria. Likely the most proximal of these events to muscarinic receptor activation, mitochondrial Bax accumulation, also was attenuated by oxotremorine-M treatment after treatment with H(2)O(2) or rotenone. These results demonstrate that stimulation of muscarinic receptors provides substantial protection from DNA damage, oxidative stress, and mitochondrial impairment, insults that may be encountered by neurons in development, aging, or neurodegenerative diseases. These findings suggest that neurotransmitter-induced signaling bolsters survival mechanisms, and inadequate neurotransmission may exacerbate neuronal loss.

Curcumin, a major active component of turmeric, has been recognized as an anticarcinogenic agent because of its propensity to induce apoptosis in vivo and in vitro. Previously, we showed that curcumin protects cells against oligonucleosomal DNA fragmentation and induces a novel apoptosis-like pathway in Jurkat cells (Piwocka et al. Exp Cell Res 249, 299-307, 1999). Here, we have studied the ability of curcumin to induce cell death in other human and rodent transformed as well as normal cells. Normal cells were quiescent or stimulated to proliferate. We showed that 50 microM pigment is able to induce cell death in all studied cells, but cell death symptoms varied for different cells. All the cells died as assessed by the TdT-mediated UTP nick end labeling method or trypan blue exclusion test. No one type of cells showed oligonucleosomal DNA fragmentation (DNA "ladder") due to curcumin action, although in HL-60 cells, we were able to observe sub-G1 formation and caspase-3 activation. Together, these data showed that curcumin induces cell death in all tested cells that can be classified as apoptosis-like, and only in HL-60 cells can it be recognized as classical apoptosis.

UVC-induced apoptotic symptoms such as morphological changes, DNA fragmentation, Bcl-2 and Bax protein expression were examined in primary splenocyte cultures from young (3 months) and old (24 months) rats. The activities of AP-1 and CRE transcription factors in UVC-irradiated splenocytes were also assessed. At 24 h after UVC irradiation 40% of cells derived from young rats were found to be apoptotic, which was twice as much as in splenocytes from old rats. Apoptosis in cells from old rats did not give typical symptoms like a "DNA ladder" and Bcl-2 protein downregulation, in contrast to splenocytes from young rats. No AP-1 transcription factor activity was found in UVC-irradiated splenocytes from old animals and only a trace activity in splenocytes from young animals. This indicates that, UVC-induced apoptosis in rat splenocytes is practically AP-1 independent and that cells from old rats are less sensitive to UVC irradiation than splenocytes from young rats.

Curcumin (CUR) is a natural yellow dye with antioxidant and scavenging properties present in Curcuma species. It is widely used as an anti-inflammatory, anti-mutagenic and chemopreventive agent. In addition to its inhibitory effect on proliferation, CUR has recently been shown to block dexamethasone-induced programmed cell death (apoptosis) of rat thymocytes. Because cellular thiols seem to play a role in redox regulation of apoptosis, the mechanism of the anti-apoptotic effect of CUR was studied by examining the levels of glutathione and acid-soluble sulfhydryl groups. CUR was shown to prevent the glutathione loss occurring in dexamethasone-treated thymocytes, enhancing intracellular glutathione content at 8 hr to 192% of that of nontreated cells. A 60% increase in acid-soluble sulfhydryl groups was also observed. In the presence of L-buthionine S,R-sulfoximine (BSO, an inhibitor of glutathione synthesis), intracellular glutathione content of thymocytes treated with dexamethasone and CUR fell to 31% and that of the acid-soluble sulfhydryl groups to 23% of control after 8 hr. Unexpectedly, the electrophoretic and flow cytometric studies of DNA fragmentation demonstrated that apoptosis did not occur even after 20 hr of incubation with buthionine S,R-sulfoximine and dexamethasone, while control thymocytes and the cells treated only with buthionine S,R-sulfoximine showed DNA fragmentation at a level corresponding to spontaneous apoptosis. These results show that CUR treatment elevated the concentrations of glutathione and nonprotein sulfhydryl groups, thus preventing their decrease in apoptotic thymocytes. Coadministration of L-buthionine S,R-sulfoximine and CUR did not affect the anti-apoptotic effect of CUR suggesting a glutathione-independent mechanism of cell protection.