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At least 199 records · Page 11Linked to original sources
PubMed1999

A review of the volatile metabolites of fungi found on wood substrates.

The holdings of eight collections of fungi have been examined for organisms isolated from wood and/or trees. Further selection of these fungi has been made according to their reported ability to produce volatile, biologically active metabolites. It is emphasized that the isolates in the collections do not necessarily produce such metabolites. The list of fungi fulfilling these conditions is slightly augmented by reports we have found in the literature, where the fungi concerned have not yet been deposited. The biochemistry of these compounds is considered with particular emphasis on their biosynthesis including that by Homo sapiens. The physiological and toxicological activity of these metabolites is reviewed especially with reference to their potential role in the complex symbioses existent in, for example, a tree. The review concludes with a discussion of areas of botany deserving increased attention in the hope that this will stimulate further work. The statements in the review are based on 173 references.

Acetylene↗
PubMed1994

Ethnobotany, drug development and biodiversity conservation--exploring the linkages.

Numerous ethnobotanical studies aimed at identifying new pharmaceutical products have been initiated in recent times. Ethnobotany has once again become a recognized tool in the search for new pharmaceuticals. Initiatives by governmental agencies and the private sector have helped spark this renewal. Many of these projects are interdisciplinary efforts involving scientists from the fields of anthropology, botany, medicine, pharmacology and chemistry. The Belize Ethnobotany Project links pharmaceutical prospecting with the conservation of traditional medical systems and biological resources. It illustrates the concept of the 'ethno-biomedical reserve' and provides an opportunity for pharmaceutical and herbal industries to contribute to the conservation effort. Terra Nova Rainforest Reserve is an ethno-biomedical reserve in Belize that was given legal status in June of 1993. Too often the exploitation of wild harvested resources has led to their severe degradation. There is a need for increased efforts to develop technologies to sustain their extraction.

Antineoplastic Agents↗
PubMed1991

Historical study: Johann Gregor Mendel 1822-1884.

The life and personality of Johann Gregor Mendel (1822-1884), the founder of scientific genetics, are reviewed against the contemporary background of his times. At the end are weighed the benefits for Mendel (as charged by Sir Ronald Fisher) to have documented his results on hand of falsified data. Mendel was born into a humble farm family in the "Kuhländchen", then a predominantly German area of Northern Moravia. On the basis of great gifts Mendel was able to begin higher studies; however, he found himself in serious financial difficulties because of his father's accident and incapacitation. His hardships engendered illness which threatened continuation and completion of his studies until he was afforded the chance of absolving successfully theological studies as an Augustinian monk in the famous chapter of St. Thomas in Altbrünn (Staré Brno). Psychosomatic indisposition made Mendel unfit for practical pastoral duties. Thus, he was directed to teach but without appropriate state certification; an attempt to pass such an examination failed. At that point he was sent to the University of Vienna for a 2-year course of studies, with emphasis on physics and botany, to prepare him for the exam. His scientific and methodologic training enabled him to plan studies of the laws of inheritance, which had begun to interest him already during his theology training, and to choose the appropriate experimental plant. In 1865, after 12 years of systematic investigations on peas, he presented his results in the famous paper "Versuche über Pflanzenhybriden." Three years after his return from Vienna he failed to attain his teaching certification a second time. Only by virtue of his exceptional qualifications did he continue to function as a Supplementary Professor of Physics and Natural History in the two lowest classes of a secondary school. In 1868 he was elected Abbot of his chapter, and freed from teaching duties, was able to pursue his many scientific interests with greater efficiency. This included meteorology, the measurement of ground water levels, further hybridization in plants (a.o. involving the hawk week Hieracium up to about 1873), vegetable and fruit tree horticulture, apiculture, and agriculture in general. This involved Mendel's active participation in many organizations interested in advancing these fields at a time when appropriate research institutes did not exist in Brünn. Some of the positions he took in his capacity of Abbot had severe repercussions and further taxed Mendel's already over-stressed system. The worst of these was a 10-year confrontation with the government about the taxation of the monastery.(ABSTRACT TRUNCATED AT 400 WORDS)

Austria↗
PubMed1995

[Not Available].

Dutch science flourished in the late sixteenth and in the seventeenth century thanks to the immigration of cartographers, botanists, mathematicians, astronomers and the like from the Southern Netherlands after the Spanish army had captured the city of Antwerp in 1585, and thanks to the religious and the socio-economic situation of the country. A strong impulse for practical scientific activities started from the Reformation, mainly thanks to its anti-traditional attitude, which had an anti-rationalistic tendency. Therefore, in the Northern Netherlands there was no 'warfare' between science and religion and the biblical arguments leading to Galileo's condemnation were not used. Although the growth of the exact sciences and of technology in the late sixteenth and the seventeenth centuries in Protestant circles may be partly attributed to the expansion of trade, industry, navigation and so on, this does not explain why there was also at the same time a great interest in subjects as botany and zoology, which had no immediate economic utility. There were discussions about Copernicanism and Cartesianism. So a number of astronomers and theologians rejected the earth's movement on scientific and religious grounds, but there were also those who did not reject the Copernican system on biblical grounds. In the seventeenth century there was much discussion between science and religion in the Northern Netherlands, but that discussion was not followed by censure by the Church of the State. In the Republic there was a large amount of intellectual freedom in the study of the natural sciences, thanks to practical and ideological considerations. In the eighteenth century the seventeenth century tension between science and religion changed into a physicotheological natural science. It was believed that investigations into the workings of nature should lead to a better understanding of its Creator. So Bernard Nieuwentijt in his well-known book: The right use of world views for the conviction of atheists and unbelievers (1715) intended to prove the existence of God on the basis of teleological arguments.

History, 16th Century↗
PubMed2006

Reliable DNA ploidy determination in dehydrated tissues of vascular plants by DAPI flow cytometry--new prospects for plant research.

BACKGROUND: Only fresh plant material is generally used for rapid DNA ploidy estimation by flow cytometry (FCM). This requirement, however, substantially limits convenient FCM application in plant biosystematics, population biology, and ecology. As desiccation is a routine way for sample preservation in field botany, potential utilization of dehydrated tissues of vascular plants in FCM research was examined. METHODS: Standard DAPI protocol was employed to evaluate the performance of 60 air-dried species, spanning more than 100-fold range of nuclear DNA amounts. Multiploid Vaccinium subg. Oxycoccus was selected as model taxon for detailed investigation and cytotype comparison. RESULTS: A majority of analyzed plants yielded distinct peaks with reasonable coefficients of variation after several months of storage at room temperature. Fluorescence intensity of nuclei isolated from desiccated tissues was highly comparable with that for fresh material, allowing reliable DNA ploidy estimation. Deep-freezer preservation substantially extended Vaccinium samples lifetime (at least to 3 years) and maintained high histogram resolution. CONCLUSIONS: The introduced approach eliminates the need for fresh material in many vascular plants and thus opens new prospects for plant FCM. Convenient cytotype investigation in field research and retrospective ploidy determination in already herbarized samples are among the principal advantages.

DNA, Plant↗
PubMedDate not supplied

Phlorizin: a review.

The dihydrochalcone phlorizin is a natural product and dietary constituent found in a number of fruit trees. It has been used as a pharmaceutical and tool for physiology research for over 150 years. Phlorizin's principal pharmacological action is to produce renal glycosuria and block intestinal glucose absorption through inhibition of the sodium-glucose symporters located in the proximal renal tubule and mucosa of the small intestine. This review covers the role phlorizin has played in the history of diabetes mellitus and its use as an agent to understand fundamental concepts in renal physiology as well as summarizes the physiology of cellular glucose transport and the pathophysiology of renal glycosuria. It reviews the biology and pathobiology of glucose transporters and discusses the medical botany of phlorizin and the potential effects of plant flavonoids, such as phlorizin, on human metabolism. Lastly, it describes the clinical pharmacology and toxicology of phlorizin, including investigational uses of phlorizin and phlorizin analogs in the treatment of diabetes, obesity, and stress hyperglycemia.

Animals↗
PubMedDate not supplied

The evolution of screening.

Botany is usually considered to be the gentlest of sciences with botanists being regarded as people who study relatively safe specimens, compared with, for example, anthropologists or microbiologists. However, botanists have their moments, particularly when collecting new species. The great botanists of the eighteenth and nineteenth centuries risked their lives in collecting and bringing back species, which we now take for granted, and Robert Brown was one of these adventurers, a young Scot who accompanied Sir Joseph Banks to New Holland. It was not, however, for his adventurous lifestyle that Brown is remembered but for his startling observation of the movements of pollen grains on a microscope slide. He noted that the pollen grains were in perpetual agitated motion, without purpose or direction but full of energy. This motion, called Brownian motion, arises from the movement of molecules, and Brownian motion is the term that has been applied to much of healthcare, including many screening programmes, which have in the past been marked more by the amount of energy and activity than by a clear sense of direction or positive achievement.

Breast Neoplasms↗
PubMed2003

Ephedra in perspective--a current review.

Although the traditional use of Ephedra 'ma huang' has been established for thousands of years, its resurgence in the US as a herbal dietary supplement is currently a matter of national controversy. At the heart of the debate are three important questions: (1) the identity and composition of Ephedra products with regard to ephedrine and related alkaloids; (2) the potential therapeutic utility of Ephedra supplements for weight loss or performance enhancement; and (3) potential health risks associated with such uses of Ephedra, particularly in sensitive individuals or in cases of intentional abuse for its stimulant properties. This review surveys the literature on Ephedra with regard to traditional uses, botany, chemistry, analytics, pharmacological effects and health risks. A brief discussion of the central issues in the current debate on the regulation of Ephedra in the United States is included as this is where most of the problems have occurred to date.

Central Nervous System Stimulants↗
PubMed2005

Ritual use of plants with possible action on the central nervous system by the Kraho Indians, Brazil.

The aim of the present study was to document the use of plants, probably acting on the central nervous system (CNS), in rituals carried out by the Kraho Indians, who occupy the cerrado biome in the central region of Brazil. The 2 years of fieldwork were guided by methods of anthropology and botany. The local shamans have indicated 286 formulas, consisting of 138 plant species in 50 uses that could be associated with some type of action on the CNS; of which 98 formulas, 87 plants and 25 uses, appear to involve psychoactive properties, such as: 'to get slow', 'stimulant effect', 'to calm down', 'to enhance memory', 'to reduce anxiety' and 'to induce sleep'. Phytochemical and pharmacological literature data were queried to establish any correlation between indigenous knowledge and scientific indications, for each one of the 138 plant species. Studies were available for 11 of these plants; and for two of them, scientific data coincided with indigenous information.

Brazil↗
PubMed2006

Plants and animals utilized as medicines in the Jaú National Park (JNP), Brazilian Amazon.

This article examines the therapeutic practices of the inhabitants of Jaú National Park (JNP), state of Amazonas, the most important feature of this region being its rich biodiversity associated with isolation in regard to conventional medical services. Seven months of field work were guided by methods of anthropology and botany. A total of 120 plants and 29 animals were utilized in 519 recorded uses comprising 81 therapeutic purposes. These were grouped under 15 categories of use, including: gastrointestinal disturbances, inflammatory processes, genitourinary disturbances, fever, mishaps with animals, dermatological problems, pain, osteomuscular problems and tropical diseases. Those who administer these medicines are local residents specializing in household remedies and other groups of healers such as rezadores - prayer-maker; curadores - healers; parteiras - midwives; desmintidores - masseurs and médiuns - mediums. At least 10 of the 120 plants species cited in this study are also utilized by other inhabitants of the Amazon region and for the same uses; some of these plants had already been studied from a pharmacological point of view. Furthermore, another six plants cited by the JNP caboclos belonging to the categories pain and inflammatory processes, are under investigation by groups of researchers in two Brazilian federal universities.

Animals↗
PubMed2002

History as a tool in identifying "new" old drugs.

To trace the history of a natural product and its use, it is necessary to identify to correct plant among around a half-million species. One must also know how and when harvest the plant and the morphology of location and extraction. Within the same species plant chemistry varies, depending upon climatic and soil conditions, stage of maturity and even diurnal factors. To all of these variations must be added the diagnostic ability of physicians and native healers (to distinguish between Hippocratically-trained Western physicians and whose knowledge is less formally taught). Seldom was a disease identified as we Know it today, but the constellations of symptoms described, when studied carefully within the framework historical setting of the culture, can be related to modern medicine. It is essential to study the historical contemporary usage data in the language in which those accounts were writTen. Translators are often philologists who are not sensitive to medical nuances. Modern readers of translated historical documents often are unaware of the precision the authors delivered in describing medical afflictions and their treatments. Natural product drugs are truly products of human knowledge. Because so many modern pharmaceuticals are manufactured synthetically we forget that once either the compound or its affinity had a home in a natural product. Over 2,500 years ago man first used a drug obtained from white willow bark, which was aspirin or acetylsalicylic acid. Today's scientists continue to be bewildered by just what aspirin's mechanisms of action are, discovering new modes of action, and how they relate to medical diagnostics. Whatever the science of aspirin, an intelligent person today takes it just as our ancestors did fo millennia. Throughout time, explanations continue to vary just as purpose of administration do as well. Nevertheless, aspirin is perceived as being beneficial. Historical in-use data can also be a factor in judging a drug's safety, since the records of its use provide observations made by intelligent persons over generations of employment Many historical "drugs" have crossed the line from drug to food. A number of them are now common items on our tables: coffee, tea, sugar, lemon, chocolate, pepper, to name a few The example of coffee affords useful insight. It was first employed as a drug (like tobacco), its botany and chemistry are well known, it has been in widespread use for centuries with diverse ethnic populations in a variety of preparations and amounts consumed. Still we are unsure about coffee's effect on health, the latest assertion being that the caffeine it contains may delay the onset of Alzheimer's. In contrast, the mercury drugs were in widespread use for a long period of time by many populations and that fact indicates that the toxic tolerance in humans is probably higher than as currently proscribed. The past contains important data for the scientific investigator. Like any field of research, historical investigation requires specialized knowledge, but much of that knowledge is readily accessible and employable. Rediscovery through examination of historical contemporaneous use data can be efficient and relatively easy compared to the travails of original research in pursuit of a discovery only to learn later that our ancestors had already made that discovery through trial and error in human usage. If we had started a search from the clues provided by history, presumably our discoveries would have been earlier, and we would have benefitted. As it is. we learn history but not science or else we learn science, not history. Both taken together the learning can be enhanced.

Drug Therapy↗
PubMedDate not supplied

The excitability of plant cells: with a special emphasis on characean internodal cells.

This review describes the basic principles of electrophysiology using the generation of an action potential in characean internodal cells as a pedagogical tool. Electrophysiology has proven to be a powerful tool in understanding animal physiology and development, yet it has been virtually neglected in the study of plant physiology and development. This review is, in essence, a written account of my personal journey over the past five years to understand the basic principles of electrophysiology so that I can apply them to the study of plant physiology and development. My formal background is in classical botany and cell biology. I have learned electrophysiology by reading many books on physics written for the lay person and by talking informally with many patient biophysicists. I have written this review for the botanist who is unfamiliar with the basics of membrane biology but would like to know that she or he can become familiar with the latest information without much effort. I also wrote it for the neurophysiologist who is proficient in membrane biology but knows little about plant biology (but may want to teach one lecture on "plant action potentials"). And lastly, I wrote this for people interested in the history of science and how the studies of electrical and chemical communication in physiology and development progressed in the botanical and zoological disciplines.

Action Potentials↗
PubMed2006

Photosynthesis research in Canada from 1945 to the early 1970s.

This history traces the development of photosynthesis research in Canada from 1945 to 1975, starting with the work of Gleb(1) Krotkov and his students, Paul Vittorio, Tony(1) Bidwell, Don(1) Nelson, Jim(1) Craigie, Bruce Tregunna, Andreas Hauschild, Geoff Lister and others in the Department of Biology at Queen's University, Kingston, Ontario. They focused on the influence of taxonomy and light quality on the path of carbon into early products, photorespiration and photosynthesis in young trees. During the same period, Ken(1) Clendenning and one of the authors (PRG) at the National Research Council of Canada (NRCC) laboratory in Ottawa began studies of chloroplast photoreduction and leaf carboxylases. They were joined by Don(1) Mortimer, who showed that the path of carbon varies with species of plant and by Morris Kates, who studied phospholipid enzymology in chloroplasts and leaves. Stan(1) Holt researched the chemistry and distribution of chlorophylls in different taxa. In 1952, Ralph Lewin joined NRCC's new Atlantic Regional Laboratory in Halifax, Nova Scotia, followed by Jim Craigie, Jack McLachlan and Tony Bidwell who mainly investigated the products of photosynthesis in marine algae. Tony Bidwell continued these studies in 1959 at the Department of Botany, University of Toronto. Dave(1) Canvin joined the staff at Queen's in 1965 and became involved in solving the mystery of photorespiration. Tony Bidwell returned to Queen's in 1969 and studied photosynthesis of algal chloroplasts using an 'artificial leaf.' In 1965, Don Nelson established a group at Simon Fraser University in Burnaby, British Columbia that included his former student, Geoff Lister who produced the first photosynthetic action spectra for trees, and Bill(1) Vidaver, who showed the useful relation between chlorophyll fluorescence and photosynthetic activity. In 1970, Mário Fragata headed a group at the Université du Québec à Trois Rivières, Québec, that began with studies of Photosystem II in chloroplasts and particles.

Canada↗
PubMed1995

Phyllotaxis: the status of the field.

In the last decade important progress has been made regarding pattern recognition and generation of the phenomenon of phyllotaxis. Phyllotaxis, a central area in plant morphogenesis, proposes a challenge that reaches beyond the field of botany and whose resolution must be sought through evolutionary biology and general comparative morphology. This review summarizes the contributions in the area, redefines the challenge, and proposes an adequate framework for the study of the phenomenon.

Mathematics↗
PubMed1985

Order amidst animalcules: the Protoctista kingdom and its undulipodiated cells.

The eukaryotic microorganisms have always been studied and described in the context of Zoology (as tiny animals), Botany (as tiny plants), Mycology (as water molds) or Microbiology (as disease agents). Because their extent (as a group of about 200,000 species) and differences from the rest of life (worthy of Protoctista kingdom status) only recently has been recognized, their classification within the Plant and Animal kingdoms remains in scandalous disarray. Admitting this problem, this paper represents a step toward achieving nomenclatural order based on ultrastructural, biochemical and evolutionary considerations.

Animals↗
PubMedDate not supplied

Amazonian coca.

A general overview of various aspects of Amazonian coca (Erythroxylum coca var. ipadu) is presented. This plant is considered a distinct variety of coca which has been developed as a cultivated plant in the upper Amazon basin. It differs from typical Andean coca in morphological, physiological and chemical features as well as in the method of preparation and use by Amazonian tribes. The main topics here discussed are the history, distribution, botany, chemistry, origin, methods of preparation and use, and the effects of Amazonian coca.

Chemistry↗