Challenges in mass spectrometry

Report of the round table discussionThe reported MS round table took place within the ProteomeValley Technology Fair during the Swiss Proteomics Society 2001 Congress. It was organised by the Swiss Proteomics Society (SPS) in collaboration with FontisMedia (http://www.fontismedia. com). It was scheduled November 22(nd), 2001 from 16:40 to 18:00 at the Geneva University Hospital. The objective of the MS round table was to bring together two kinds of specialists in mass spectrometry: those who develop and commercialise MS equipment and those who use it as a tool in proteomic sciences. Six expert users and six representatives of leading MS instrument companies were thus invited to actively participate in this round table and share their points of view. The main objectives of this round table were not only to share experiences, but also to share dreams regarding MS technology and discuss the actual limits. It also focused on what MS users presently expect from MS producers and what are the current priorities in terms of development, for the benefit of all parties. Although it was one of the final events of the meeting, this MS round table attracted an audience of some fifty participants of the congress who were actively involved in the debate.     

Mycoses and zoonoses: Cryptococcus spp

The term "zoonosis" is difficult to delimit because different authors have various definitions for this term. Few mycoses are usually considered zoonoses. However, the role that animals play in the epidemiology of the main human mycoses is still not well known. Moreover, the environmental niches for these fungal agents have not yet been completely determined. This special issue of the "Revista Iberoamericana de Micología" deals with the talks and round table presented at the VIII Spanish Mycological Congress held in October 2006 in Barcelona, Spain on "Cryptococcus spp. and zoonoses".     

The mt1 melatonin receptor and RORbeta receptor are co-localized in specific TSH-immunoreactive cells in the pars tuberalis of the rat pituitary.

The pars tuberalis (PT) of the pituitary represents an important target site for the time-pacing pineal hormone melatonin because it expresses a large number of mt1 receptors. Functional studies suggest that the PT mediates the seasonal effects of melatonin on prolactin (PRL) secretion. The aim of this study was the characterization of the phenotype of melatonin-responsive cells. Furthermore, we determined whether RORbeta, a retinoid orphan receptor present in the PT, was co-expressed in the same cells. We combined nonradioactive in situ hybridization (ISH) with hapten-labeled riboprobes for detection of the receptors and immunocytochemistry (ICC) for detection of alphaGSU (alpha-glycoprotein subunit), betaTSH, betaFSH, betaLH, GH, PRL, and ACTH. Expression of mt1 mRNA was found in small round cells, co-localized with alphaGSU and betaTSH. However, not all betaTSH-containing cells expressed mt1 mRNA. The distribution of mt1- and RORbeta-positive cells appeared to overlap, although more cells were labeled for RORbeta than for mt1. Gonadotrophs, as well as other pars distalis cell types, were never labeled for mt1 melatonin receptor. Therefore, this study identifies the "specific" cells of the PT as the mt1 melatonin receptor-expressing cells.     

Melatonin in Plants: More Studies are Necessary

Melatonin (N-acetyl-5-methoxytryptamine) is a biogenic indoleamine structurally related with other important substances such as tryptophan, serotonin, indole-3-acetic acid (IAA). In mammals, birds, reptiles and fish melatonin is a biological modulator of several timing (circadian) processes such as mood, sleep, sexual behavior, immunological status, etc. Since its discovery in plants in 1995 several physiological roles, including a possible role in flowering, circadian rhythms and photoperiodicity and as growth-regulator have been postulated. Recently, a possible role in rhizogenesis in lupin has also been proposed. Here, these actions of melatonin in plant development are commented on and some other interesting recent data concerning melatonin in plants are also discussed. The need for more investigation into melatonin and plants is presented as an obvious conclusion.Key Words: antioxidant, auxin, ethylene, flowering, growth, IAA, melatonin, rhizogenesisMelatonin (N-acetyl-5-methoxytryptamine) is well known in human and animal physiology, but is an unknown player in the physiology of plants. Many studies have clearly demonstrated its presence in different parts of plants such as the root, stem, leaf, flower, fruit and seed.^1–3 In addition to its phytochemical interest (natural melatonin is absorbed by the human digestive tract), this compound has aroused attention as a possible signal molecule in plant physiology.^4,5 From it discovery in plants in 1995, some authors have postulated many physiological roles for melatonin, although, in general, research into melatonin in plants is clearly insufficient. Only the possible role of melatonin in flowering and as growth promotor have been studied with some detail. As regards the former, the studies of Kolar''s group on the role of melatonin as plant rhythm regulator provided interesting data, pointing to melatonin''s action in the later stages of the flowering process.^6,7 Melatonin seems to have a more obvious effect in the growth process of some species, as has been demonstrated by our group. Our data showed that melatonin has a growth-promoting effect on aerial organs (epi- and hypocotyls, coleoptiles) and a growth-inhibitory effect on roots, in a similar way to auxins.^8,9 Other authors, too, have provided evidence on the possible growth-promoting activity of melatonin in Glycyrrhiza uralensis, which doubled its melatonin content in roots in the 3–6 month development period.¹⁰ A more recent paper, presented data concerning the effect that melatonin has on the rhizogenesis process. Melatonin produces and/or activates the generation of root primordia and their subsequent growth into lateral roots and adventitious roots in Lupinus albus.¹¹ Studies on melatonin in vegetative plant development pointed to a relationship between IAA and melatonin but more data are necessary to identify the particular interconnection. The most recent data in this respect, established the effect of melatonin on the enzymatic activity of ACC oxidase in hypocotyls and roots of Lupinus albus, pointing to the possible regulation of ethylene production in these vegetative organs.¹²One aspect that has slowed down research into melatonin in plants is the difficulty involves in its detection, identification and measurement of melatonin in plants. Because the high degree of interference caused by melatonin-immunodetection kits using plant samples, the habitual use of the liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been crucial.¹³ The use of this sophisticated technique for melatonin identification combined with measuring levels by means of liquid chromatography with electrochemical or fluorescence detection seem to be an efficient methodological option. In this respect, studies such as that recently published by Cao et al. (2006),¹⁴ where a robust method for determining melatonin, serotonin and auxin in plant samples using LC-MS/MS was presented, clearly contribute to improving accurate research into melatonin in plants.Future studies on melatonin in plant physiology should take metabolic and molecular aspects into consideration. Thus, the participation of different enzymatic activities in melatonin biosynthesis and catabolism in plants appears to be an interesting challenge.⁵ Also, the presence of melatonin receptor(s) in plant samples would strongly suggest a role for melatonin. Other interesting aspects to be investigated are: the possible tissular transport of melatonin, its action as plant cell protector due to its excellent antioxidative properties, and its involvement in particular physiological processes such as germination, cell growth, senescence, flowering, etc. Lastly, we must not forget the involvement of melatonin in stress processes in animal cells, which may be mirrored to some extent in plant cells. As can be seen, much remains to be done.     

The melatonin message: duration versus coincidence hypotheses

Whereas there is little doubt that melatonin is an important hormone which mediates the effects of the pineal gland, there is debate concerning the nature of the melatonin message which the animal interprets. This brief resume considers the two main features of the melatonin rhythm which the organism could "read" to determine whether it is in a long or a short day. The first scheme is what is referred to as the duration hypothesis. This hypothesis depends on the fact that the changing photoperiod likewise alters the duration of the daily melatonin peak and this signals the organism as to daylength and the appropriate endocrine adjustments are made. The second possibility depends on the synchronization of elevated melatonin levels with the sensitivity of a particular organ system to the melatonin peak; when this occurs the organ responds accordingly. Both the external and internal coincidence models are considered. The duration and coincidence models are fundamentally quite different. In the case of the former, the altered duration of the melatonin peak per se determines the response that will occur. In the case of the coincidence models, the elevated melatonin has a more passive role with the "decision" to respond being a function of end organ sensitivity. In the final analysis, it may be that organisms use a combination of absolute duration of the melatonin pulse, direction of change of the melatonin rhythm, and synchrony of peak melatonin with the increased sensitivity of the end organ before a response is forthcoming.     

Mammalian photoperiodic system: formal properties and neuroendocrine mechanisms of photoperiodic time measurement

Photoperiodism is a process whereby organisms are able to use both absolute measures of day length and the direction of day length change as a basis for regulating seasonal changes in physiology and behavior. The use of day length cues allows organisms to essentially track time-of-year and to "anticipate" relatively predictable annual variations in important environmental parameters. Thus, adaptive types of seasonal biological changes can be molded through evolution to fit annual environmental cycles. Studies of the formal properties of photoperiodic mechanisms have revealed that most organisms use circadian oscillators to measure day length. Two types of paradigms, designated as the external and internal coincidence models, have been proposed to account for photoperiodic time measurement by a circadian mechanism. Both models postulate that the timing of light exposure, rather than the total amount of light, is critical to the organism's perception of day length. In mammals, a circadian oscillator(s) in the suprachiasmatic nucleus of the hypothalamus receives photic stimuli via the retinohypothalamic tract. The circadian system regulates the rhythmic secretion of the pineal hormone, melatonin. Melatonin is secreted at night, and the duration of secretion varies in inverse relation to day length; thus, photoperiod information is "encoded" in the melatonin signal. The melatonin signal is presumably "decoded" in melatonin target tissues that are involved in the regulation of a variety of seasonal responses. Variations in photoperiodic response are seen not only between species but also between breeding populations within a species and between individuals within single breeding populations. Sometimes these variations appear to be the result of differences in responsiveness to melatonin; in other cases, variations in photoperiod responsiveness may depend on differences in patterns of melatonin secretion related to circadian variation. Sites of action for melatonin in mammals are not yet well characterized, but potential targets of particular interest include the pars tuberalis of the pituitary gland and the suprachiasmatic nuclei. Both these sites exhibit uptake of radiolabeled melatonin in various species, and there is some evidence for direct action of melatonin at these sites. However, it appears that there are species differences with respect to the importance and specific functions of various melatonin target sites.     

Bioinformatics: perspectives for the future

I give here a very personal perspective of Bioinformatics and its future, starting by discussing the origin of the term (and area) of bioinformatics and proceeding by trying to foresee the development of related issues, including pattern recognition/data mining, the need to reintegrate biology, the potential of complex networks as a powerful and flexible framework for bioinformatics and the interplay between bio- and neuroinformatics. Human resource formation and market perspective are also addressed. Given the complexity and vastness of these issues and concepts, as well as the limited size of a scientific article and finite patience of the reader, these perspectives are surely incomplete and biased. However, it is expected that some of the questions and trends that are identified will motivate discussions during the IcoBiCoBi round table (with the same name as this article) and perhaps provide a more ample perspective among the participants of that conference and the readers of this text.     

First International Conference on “Biotechnology in Agriculture”

The 1st International Conference on “Biotechnology in Agriculture” was held at the Agricultural University of Tirana, Albania, from the 22nd to the 23rd of April 2014. The conference was organized as collaboration between the Agricultural University of Tirana (AUT) and the Friedrich Schiller University in Jena, Germany. About 200 scientists from different countries presented their work orally or as posters covering the three main topics of the conference: plant, animal and food biotechnology. The conference included a field trip as well to the Experimental Didactic Economy Station and a Fish Farm, both belonging to the Agricultural University of Tirana. In this report, we describe the main topics of the Conference and a summary of talks and posters presented in different sessions. The main conclusions provided at the end of the activity, the objectives for the future and a brief overview of the field trips and pre- and post-conference tours are displayed in this current report. Since the conference on “Biotechnology in Agriculture” was the first one organized in Albania and also an international one, it was of a great interest for the participants and also for the scientific community working in the biotechnology area. Therefore, one of the decisions made at the end of the conference was to hold similar conferences periodically, every two years, at AUT.     

Supporting Partners of the IAPB 14th Quadrennial Congress Dublin as of July 12th 2018

Melatonin is a ubiquitously present indoleamine with a vast capacity for modulating the growth and behavior of plants, animals, and microbes. Though melatonin was discovered in plants decades after its discovery in mammals, its presence has now been confirmed in almost all plant families. Despite this, the in vitro and in vivo mechanisms of action of melatonin are still poorly defined. Although there are an increasingly large number of investigations into the roles of melatonin in plants, few take advantage of in vitro culture systems. Melatonin has been found to possess several important roles in plant growth and development, including functions in rhythmic and cyclic processes, such as chronoregulation, seasonal and senescence processes, as well as modulation of reproductive development, control of root and shoot organogenesis, maintenance of plant tissues, and responses to biotic and abiotic stresses. This review highlights the potential for use of melatonin in several in vitro systems, the roles it plays in plant morphogenesis, and the importance of melatonin in communication within and between plants, and how in vitro systems can be exploited to better understand these understudied functions of melatonin.     

Purification of Pararosaniline and Atebrine by chromatography on lipophilic Sephadex LH-20

Synopsis Column chromatography on lipophilic Sephadex LH-20 of dyes labelled as Pararosaniline was carried out in a 3:I mixture of dimethyl sulphoxide and an aqueous ammonia-ammonium chloride buffer mixture. In such a mixture the dye, mainly in its leuco-form, is highly soluble. On elution with this mixture, a red-coloured band separated from fluorescent- and non-fluorescent-contaminating substances. This band contained the main component which could be precipated from the appropriate eluant fractions as a colourless base by adding excess dilute ammonia.The purified dye showed a slightly higher molar extinction coefficient at 54I nm than the original product. By fluorescence spectrophotometry, contrary to what was found for the original product, no fluorescent components could be detected. A similar method was found to be suitable for purifying Atebrine, an acridine-type dye.The method appears to be of general applicability for preparing purified dye fractions in quantities sufficient for histochemical and histological use.The basic principle of the method described in this paper was presented at a round table discussion at a meeting Über Farbstoffe und Farbstoffprobleme der Histologen und Histochemiker of the Gesellschaft für Histochemic on II September 1971 at Düsseldorf. The proceedings will be published inActa Histochemica.     

The Physiological Function of Melatonin in Plants

Melatonin (N-acetyl-5-methoxytryptamine), a well-known animal hormone, was discovered in plants in 1995 but very little research into it has been carried out since. It is present in different parts of all the plant species studied, including leaves, stems, roots, fruits and seeds. This brief review will attempt to provide an overview of melatonin (its discovery, presence and functions in different organisms, biosynthetic route, etc.) and to compile a practically complete bibliography on this compound in plants. The common biosynthetic pathways shared by the auxin, indole-3-acetic, and melatonin suggest a possible coordinated regulation in plants. More specifically, our knowledge to date of the role of melatonin in the vegetative and reproductive physiology of plants is presented in detail. The most interesting aspects for future physiological studies are presented.Key Words: antioxidant, auxin, flowering, growth, IAA, melatonin, plant hormone, reproductive development, rooting, vegetative developmentMelatonin (N-acetyl-5-methoxytryptamine), an “old friend” and well known as an animal hormone but “new” to plant biology is arousing great interest due to its broad distribution in the biological kingdom and the recent data on its possible physiological role in plants. Many studies on melatonin, as a phytochemical compound with potentially interesting health-related properties, have recently appeared, but no more than 15–20 papers with a plant physiological focus have been published since 1995. Besides mentioning the most interesting data on melatonin related with plants, this review will hopefully trigger more studies into this molecule to deepen our understanding of the different physiological roles that it might play in plants. We shall briefly look at the well-known function of melatonin in vertebrates, its discovery in plants and other organisms, and its presence in plants as a possible medicinal phytochemical. The joint biosynthetic pathways of melatonin and the auxin indole-3-acetic acid (IAA) will be described. Thus, we reveal the new and emerging field of melatonin studies in plants, the limited physiological data available and its possible role in plants.     

Quantify this! Report on a round table discussion on quantitative mass spectrometry in proteomics

Following the success of the first round table in 2001, the Swiss Proteomic Society has organized two additional specific events during its last two meetings: a proteomic application exercise in 2002 and a round table in 2003. Such events have as their main objective to bring together, around a challenging topic in mass spectrometry, two groups of specialists, those who develop and commercialize mass spectrometry equipment and software, and expert MS users for peptidomics and proteomics studies. The first round table (Geneva, 2001) entitled "Challenges in Mass Spectrometry" was supported by brief oral presentations that stressed critical questions in the field of MS development or applications (St?cklin and Binz, Proteomics 2002, 2, 825-827). Topics such as (i) direct analysis of complex biological samples, (ii) status and perspectives for MS investigations of noncovalent peptide-ligant interactions; (iii) is it more appropriate to have complementary instruments rather than a universal equipment, (iv) standardization and improvement of the MS signals for protein identification, (v) what would be the new generation of equipment and finally (vi) how to keep hardware and software adapted to MS up-to-date and accessible to all. For the SPS'02 meeting (Lausanne, 2002), a full session alternative event "Proteomic Application Exercise" was proposed. Two different samples were prepared and sent to the different participants: 100 micro g of snake venom (a complex mixture of peptides and proteins) and 10-20 micro g of almost pure recombinant polypeptide derived from the shrimp Penaeus vannamei carrying an heterogeneous post-translational modification (PTM). Among the 15 participants that received the samples blind, eight returned results and most of them were asked to present their results emphasizing the strategy, the manpower and the instrumentation used during the congress (Binz et. al., Proteomics 2003, 3, 1562-1566). It appeared that for the snake venom extract, the quality of the results was not particularly dependant on the strategy used, as all approaches allowed Lication of identification of a certain number of protein families. The genus of the snake was identified in most cases, but the species was ambiguous. Surprisingly, the precise identification of the recombinant almost pure polypeptides appeared to be much more complicated than expected as only one group reported the full sequence. Finally the SPS'03 meeting reported here included a round table on the difficult and challenging task of "Quantification by Mass Spectrometry", a discussion sustained by four selected oral presentations on the use of stable isotopes, electrospray ionization versus matrix-assisted laser desorption/ionization approaches to quantify peptides and proteins in biological fluids, the handling of differential two-dimensional liquid chromatography tandem mass spectrometry data resulting from high throughput experiments, and the quantitative analysis of PTMs. During these three events at the SPS meetings, the impressive quality and quantity of exchanges between the developers and providers of mass spectrometry equipment and software, expert users and the audience, were a key element for the success of these fruitful events and will have definitively paved the way for future round tables and challenging exercises at SPS meetings.     

The harvesting of cranial bone grafts: a guided osteotome

A technique for in situ harvesting of the outer table of the skull using a "guided" osteotome is presented. While guards have been placed to control the depth of the blade, additional steps are advised to ensure the highest level of safety in clinical use: Before harvesting the graft, a full set of anteroposterior and lateral x-rays should be examined to determine which areas of the skull are thin and should be avoided. All areas with cranial sutures should be avoided because here the dura is more firmly attached to the inner table making perforation more dangerous. Bone should not be harvested under the hairless forehead region because this results in a visible depression. The surgeon should use the guards as guides to visually monitor the depth of the blade. The surgeon should not attempt the procedure without having a set of three different depths (1 mm, 2 mm, and 3 mm) available. Different skulls have different thicknesses of the outer table, and the technique loses the advantage of safety if an inappropriate depth is used.     

Melatonin and clinical application.

A review of the different publications dealing with melatonin in humans shows that this field has been very active in the last few years. Normative melatonin values have been defined. Various relationships between melatonin and other traits have been studied, such as sleep, circadian rhythm, surgical stress and anaesthesia. Age-related melatonin studies and melatonin during depression and other psychiatric disorders have been reviewed. Finally, some studies have been performed to use melatonin as a medication for sleep disturbance in depression, for jet-lag and as a skin protector for ultraviolet light.     

The science behind pre-Columbian evidence of syphilis in Europe: research by documentary

This article discusses the presentation of scientific findings by documentary, without the process of peer review. We use, as an example, PBS's "The Syphilis Enigma," in which researchers presented novel evidence concerning the origin of syphilis that had never been reviewed by other scientists. These "findings" then entered the world of peer-reviewed literature through citations of the documentary itself or material associated with it. Here, we demonstrate that the case for pre-Columbian syphilis in Europe that was made in the documentary does not withstand scientific scrutiny. We also situate this example from paleopathology within a larger trend of "science by documentary" or "science by press conference," in which researchers seek to bypass the peer review process by presenting unvetted findings directly to the public.     

Melatonin circadian-stage-dependently delays breast tumor development in mice injected daily for several months

Breast tumor incidence is compared in C3CF1 mice, receiving at one of 6 different circadian stages, daily injections of melatonin or of a vehicle or no treatment, the latter in a slightly cooler environment. Results are summarized when approximately 33% of all animals have a breast tumor. Vehicle treatment increases tumor incidence. This environment-handling-vehicle effect is reduced by injecting melatonin, as indicated by life table analysis. A circadian-stage-dependence of the melatonin effect is suggested by the statistical significance of a 12-h component fitted to the tumor incidence data. The administration time of melatonin is an indispensable complement to dosing, notably when effects upon tumorigenesis are involved.     

Growth activity,rooting capacity,and tropism: three auxinic precepts fulfilled by melatonin

Plant melatonin appears to be a multiregulatory molecule with multiple functions similar to those observed in animals. It induces growth in stems and stimulates root generation. It is also able to delay senescence by protecting photosynthetic systems and related processes. One of the most studied actions of melatonin is its effect on biotic and abiotic stresses in the plant, such as that produced by drought, extreme temperatures, chemical pollution, UV radiation, etc. Recent data have demonstrated its role as a modulator of gene expression in plants. In this review, we compare studies which show that melatonin behaves in a similar way to auxin, and present data that relate the physiological responses produced by melatonin with the action of auxin, such as promoting/inhibiting growth activity and rooting capacity. In addition, for the first time, the data presented demonstrate the possible involvement of melatonin in the tropic response of roots. The possible role of melatonin as a plant regulator and its relationship with auxin action and the signaling molecule nitric oxide is presented and discussed in a hypothetical model.     

A review on melatonin action as therapeutic agent in cancer

Background

Melatonin is a hormone which is produced from pineal gland in human and is said to have various impacts in human body like controlling sleep wake cycle, regulating the immune and cardiovascular system and regulating the peripheral organ functioning to name a few. Researchers have reported that the melatonin levels correlates with cancer risks.

Objective

In this review article, focus has been given to the therapeutic applications and impact of melatonin hormone in human behavior and physiologic activities. Through this article we aim in compiling the scattered information regarding melatonin and its various aspects of importance in human system.

Methods

We made an analysis of existing hypothesis and studies published on melatonin and circadian rhythm, factors effecting Melatonin secretions in body, sleep disturbances and cancer risks and melatonin therapy in cancer patients.

Results

Melatonin’s role as an endogenous synchronizer, growing evidence suggests its anti-oxidative activity as well as its having a role in modulating immune responses. Fluctuating melatonin levels can be boosted by ingesting products containing melatonin. A large portion of the examinations detailed by the researchers clearly conclude that keeping up an impeccable sleep-wake cycle and having a healthy diet is extremely important to keep up the regular melatonin levels and in order to stay fit.

Conclusions

Melatonin is considered as a critical hormone that controls and regulates many functions in our body. Melatonin production is emphatically related to the night time duration. Its most absolute biological role is to convey information to the body about day length for a variety of physiologic functions. In addition to melatonin’s role as an endogenous synchronizer, growing evidence suggests its anti-oxidative activity as well as its having a role in modulating immune responses. At present, a growing interest is focused on the validity of the anti-tumor mechanisms of melatonin.

     

Melatonin and the circadian rhythms of feeding and perch-hopping in the European starling,Sturnus vulgaris

Summary The role of melatonin plasma titers in the control of free-running circadian rhythms was investigated in European starlings,Sturnus vulgaris, held in continuous dim light. Simultaneous recordings of plasma melatonin, perch-hopping and feeding activity revealed synchronous circadian variations in all three functions with high melatonin titers during resting and low titers during activity periods. Implanting birds with melatonin silastic capsules resulted in a 100-fold increase in plasma concentrations and an abolition of the endogenous melatonin rhythm. Feeding rhythms persisted during this treatment, although the activity time () was lengthened and the circadian period () shortened. Similar changes were found in perchhopping activity, but in some birds, this activity was more or less suppressed. These data demonstrate that although melatonin plasma titers freerun synchronously with other circadian parameters, fluctuations in peripheral melatonin are not essential for the expression of circadian activity.