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Herbal therapy: an ancient and modern medicine for pain
No full textPain is an important defense reaction. Recurrent
and persistent pain, though, is the most frequent font
of sufference for humans. All civilizations, in the past
and at the present, has looked to find methods of
fighting pain. Many ancient cultures believed pain
and disease were punishment for human folly and
they tried to appease angry gods with rituals. After,
herbal medicine has been one of the more developping
way to try to control pain. The major part of the
remedies that come from the past (even from
millennia) has crossed the centuries and they still are
advantageous, often with their derivatives, for
obtaining analgesia. In this chapter, we discuss
phytotherapeutic agents which are the more used for
pain control, considering the historical aspects as
well as the modern uses. In particular, we take into
consideration the opium agents and the derivaties of
Salix Alba, which both are progenitor of the most
used analgesics (narcotic and non narcotic). Also, we consider the cannabinoids as old remedies which have interesting future perspectives in
pain therapy. Finally, we reports on the ergot derivatives as an example of herbal agents
which are used in particular pain conditions such as the primary headaches.
Over one-third of the world's population suffers from persistent or recurrent pain
(1), often associated with conditions such as back injury, migraine headaches, arthritis,
herpetic and diabetic neuropathy, cancer. Chronic pain results not just from the
physical insult but also from a combination of physical, emotional, psychological, and
social abnormalities. Because many pains persist after an insult is healed, the ongoing
pain rather than the injury underlies the patient's disability. Untreated pain may become
self-perpetuating because pain has immunosuppressive effects that leave patients
susceptible to subsequent diseases.
It is now clear that if we can effectively treat the pain despite the underlying cause, it
will be possible for patients to regain normal functioning. The key to more successful
pain treatment is to understand the mechanisms that generate and perpetuate chronic
pain. Major advances have occurred at levels spanning from molecular studies that have
identified transduction proteins in nociceptors to cortical imaging studies which reveal
how pain is experienced on a cognitive level (2,3). Two key lines of discovery have been
molecular/cellular transduction mechanisms and neuronal plasticity.
Since the beginning of the present century, theories of pain mechanism have evolved
from specificity and summation models to the popular gate control theory. This latter
pain theory, proposed by Melzack/Wall/Casey, has become the most important
development in the field of pain management. Discoveries in recent years show that pain
perception is no longer a straight forward afferent transmission of pain signal. It is a
complex mechanism involving modulation coming from both peripheral and central
nervous system. In the chronic pain state, pain signal generation can actually in the
central nervous system without peripheral noxious stimulation.
Anatomically, there are numerous ascending excitatory and descending inhibitory
pathways in pain signal transmission. Centralization (cephalad relocation in the central
nervous system) of the pain signal generators occur spontaneously or after these neural
pathways are interrupted, leading to totally unexpected pain syndromes. Advanced reflex
sympathetic dystrophy, deafferentation pain and phantom pain phenomenon are just a
few examples.
Traditionally, we suppose that pain is an important biological reaction of defense
and a fortunate warning to put us on our guard against diseases. This may be true in
disease states such as appendicitis, fracture and angina. It does not explain the
unnecessary pain in conditions such as migraine, post-therapeutic neuralgia and pain in
labor and delivery.
Scientific evidence shows that acute persistent pain eventually sensitizes wide
dynamic neurons in the dorsal horn of the spinal cord ("wind-up phenomenon"),
constituting the basis of developing chronic pain syndromes. Persistent and excessive
pain has no biological function. It is actually harmful to our well being. Therefore, pain
needs to be treated as early and as completely as possible.
Pain can be classified into five different types: visceral, somatic, referred,
neuropathic and psychogenic, according to their origins of pain signal generation.
Commonly, we see pain syndromes with different mixtures of these five types. In acute
pain (predominantly nociceptive), visceral, somatic and referred mechanisms play important roles in the pain perception. In chronic pain (frequently non-nociceptive),
neuropathic and psychogenic mechanisms prevail, resulting in protracted suffering and
disability both physically and mentally.
In pain management, modulation of pain signal transmission is a far better choice
than destruction. Despite the dramatic improvement in the knowledge of nociception
pathophysiology the more effective pain medications are still remedy which was used in
the traditional medicine from centuries or derivatives of those
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Pectin and zinc alginate: The right inner/outer polymer combination for core-shell drug delivery systems
No full textCore-shell beads loaded with betamethasone were developed using co-axial prilling as production technique and pectin plus alginate as polymeric carriers. During this study, many operative conditions were intensively investigated to find the best ones necessary to produce uniform core-shell particle systems in a reproducible way. Particularly, feed solutions’ composition, polymers mass ratios and the effect of the main process parameters on particles production, micromeritics, inner structure, drug loading and drug-release/swelling profiles in simulated biological fluids were studied. The optimized core-shell formulation F5 produced with a pectin core concentration of 4.0% w/v and an alginate shell concentration of 2.0% w/v (2:1 core:shell ratio) acted as a sustained drug delivery system. It was able to reduce the early release of the drug in the upper part of the gastro-intestinal tract for the presence of the zinc-alginate gastro-resistant outer layer and to specifically deliver it in the colon, thanks to the selectivity of amidated low methoxy pectin core for this district. Therefore, these particles may be proposed as colon targeted drug delivery systems useful for inflammatory bowel disease (IBD) therapy
Utilizzo delle colture in vitro per la produzione di metaboliti secondari
No full textPlant secondary metabolites are known to
play a major role in the adaptation of plants to their
environment. Production from spontaneous or cultivated
plants is affected by environmental and physiological
factors. Plant cell cultures have been suggested
as a feasible technology for the production of plant
derivedm etabolites. Few industrial lines having high
production, have been obtained on the base of experimental
studies
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