Introduction: The importance of tropical medicine cannot be overstated, since by the end of the 2030s, most humans will live in the tropics and will need protection from tropical diseases. ...Nevertheless, until now, there are no bibliometric studies about tropical medicine as a whole; all previous studies are limited to diseases, countries or particular journals, and are often limited to brief periods of time. Here we present an analysis of historical trends for the world and for the Revista de Biología Tropical in celebration of the journal’s 70th anniversary.
Objective: To assess geographic and historical trends in the study of tropical medicine included in a general database, the Web of Science and from a detailed analysis of one journal of particular importance for the field in the neotropical region.
Methods: We limited our data to journals covered by the Web of Science category “tropical medicine” in the Science Citation Index Expanded (data updated 19 January 2022) and the Journal Citation Report on 30 June 2021.
Results: We retrieved 69 480 articles, of which 44 % resulted from international collaboration with 194 participating countries; articles may reach 17–21 citations each, and the countries with outstanding results in the database include USA, Brazil, UK, Kenya and Switzerland. Research focus changes as diseases such as HIV, Dengue and tuberculosis become more or less important over time, but overall there was much research on Plasmodium, leishmaniasis and schistosomiasis. The journal Revista de Biología Tropical has significantly increased the number of topics covered, but still publishes studies about tropical biomedical subjects.
Conclusions: While countries with large research budgets have a large presence in this database, lower income tropical countries like Brazil and Kenya have done a remarkable contribution in the field of tropical medicine. The Revista de Biología Tropical has been publishing quality research about tropical medicine for the last seven decades.
ABSTRACT
Background
An adequate response to health needs to include the identification of research patterns about the large number of people living in the tropics and subjected to tropical diseases. ...Studies have shown that research does not always match the real needs of those populations, and that citation reflects mostly the amount of money behind particular publications. Here we test the hypothesis that research from richer institutions is published in better-indexed journals, and thus has greater citation rates.
Methods
The data in this study were extracted from the Science Citation Index Expanded database; the 2020 journal Impact Factor (IF2020) was updated to 30 June 2021. We considered places, subjects, institutions and journals.
Results
We identified 1041 highly cited articles with ≥100 citations in the category of tropical medicine. About a decade is needed for an article to reach peak citation. Only two COVID-19–related articles were highly cited in the last 3 y. The most cited articles were published by the journals Memorias Do Instituto Oswaldo Cruz (Brazil), Acta Tropica (Switzerland) and PLoS Neglected Tropical Diseases (USA). The USA dominated five of the six publication indicators. International collaboration articles had more citations than single-country articles. The UK, South Africa and Switzerland had high citation rates, as did the London School of Hygiene and Tropical Medicine in the UK, the Centers for Disease Control and Prevention in the USA and the WHO in Switzerland.
Conclusions
About 10 y of accumulated citations is needed to achieve ≥100 citations as highly cited articles in the Web of Science category of tropical medicine. Six publication and citation indicators, including authors’ publication potential and characteristics evaluated by Y-index, indicate that the currently available indexing system places tropical researchers at a disadvantage against their colleagues in temperate countries, and suggest that, to progress towards better control of tropical diseases, international collaboration should increase, and other tropical countries should follow the example of Brazil, which provides significant financing to its scientific community.
Atomic force microscopy (AFM) is a popular tool for evaluating the mechanical properties of biological materials (cells and tissues) at high resolution. This technique has become particularly ...attractive to cancer researchers seeking to bridge the gap between mechanobiology and cancer initiation, progression, and treatment resistance. The majority of AFM studies thus far have been extensively focused on the nanomechanical characterization of cells. However, these approaches fail to capture the complex and heterogeneous nature of a tumor and its host organ. Over the past decade, efforts have been made to characterize the mechanical properties of tumors and tumor-bearing tissues using AFM. This has led to novel insights regarding cancer mechanopathology at the tissue scale. In this Review, we first explain the principles of AFM nanoindentation for the general study of tissue mechanics. We next discuss key considerations when using this technique and preparing tissue samples for analysis. We then examine AFM application in characterizing the mechanical properties of cancer tissues. Finally, we provide an outlook on AFM in the field of cancer mechanobiology and its application in the clinic.
Immune evasion-a well-established cancer hallmark-is a major barrier to immunotherapy efficacy. While the molecular mechanisms and biological consequences underpinning immune evasion are largely ...known, the role of tissue mechanical stresses in these processes warrants further investigation. The tumor microenvironment (TME) features physical abnormalities (notably, increased fluid and solid pressures applied both inside and outside the TME) that drive cancer mechanopathologies. Strikingly, in response to these mechanical stresses, cancer cells upregulate canonical immune evasion mechanisms, including epithelial-mesenchymal transition (EMT) and autophagy. Consideration and characterization of the origins and consequences of tumor mechanical stresses in the TME may yield novel strategies to combat immunotherapy resistance. In this Perspective, we posit that tumor mechanical stresses-namely fluid shear and solid stresses-induce immune evasion by upregulating EMT and autophagy. In addition to exploring the basis for our hypothesis, we also identify explicit gaps in the field that need to be addressed in order to directly demonstrate the existence and importance of this biophysical relationship. Finally, we propose that reducing or neutralizing fluid shear stress and solid stress-induced cancer immune escape may improve immunotherapy outcomes.
While roads are indispensable for modern civilization and beneficial for many wildlife species, they have been causing mortality from collisions since high speed chariots were invented 4 000 years ...ago. Most scientific work about road kill has been done in temperate ecosystems, but some authors have suspected that they have different characteristics in tropical ecosystems. In this review, I summarize publications that focus on road kills in tropical countries from Africa, America, Asia and Oceania. I found 73 studies that focus on tropical road kills. Output increased after 2011 and the most productive countries, in articles per capita, are Costa Rica, Colombia and Brazil. Most studies report that mammals are the main victims, but bird deaths are severely underestimated and amphibians suffer mass mortality in reproductive concentrations. Every road victim is itself a small ecosystem that contains thousands of microscopic species, but “Road Kill Microbiology” is yet to be developed as a new branch of research. No generalization can be made about the role of season or habitat in road kills because pooled data hide individual trends: researchers should keep separate records by age, sex, species, time of day, season and place; otherwise important patterns will be missed. There is not a single study, tropical or temperate, that can completely answer how many animals are killed, where, or when, because many victims are removed by scavengers, end outside the road or are too small to be noticed. Significant contributions from the tropics include emphasis on the ethical use of road kill for research, inclusion of species other than wild vertebrates, study of often overlooked phenomena like hour of day and failed versus successful crossing attempts, and the value of speed control in mitigation. The so-called “citizen science” can identify the most affected species but produces data that are very different from those generated by professional scientists in terms of the proportion of affected groups. Real speed limitation is the simplest effective mitigation measure. Tropical scientists should concentrate on monitoring and experimental studies to fully understand the ecology of road kills and to make a contribution that matches what rich countries do. Rev. Biol. Trop. 66(2): 722-738. Epub 2018 June 01.
Lichens are traditionally divided into types such as "crustose", "foliose" and "fruticose", with different shapes and heights. Substrate, temperature and water are thought to affect lichen height, ...but there are few studies regarding tropical paramo lichens. Along 2015 I measured those variables in the terricolous lichens of the Cerro Buena Vista, paramo (Costa Rica, 9°33' N & 83°45' W). The measurements were taken inside the lichens and in the substrate under them, in 61 randomly located quadrats (50 x 50 cm). Lichens grew taller on (1) warmer ground, (2) wetter ground, (3) the moister Caribbean slope, and (4) the season with heavier rainfall, as expected. Apparently, atmospheric factors are more important than substrate in the determination of temperature, relative humidity and growth of lichens. Physiologically available water seems to be the main determinant of lichen vertical growth in the Buena Vista paramo.
Velvet worms, also known as peripatus or onychophorans, are a phylum of evolutionary importance that has survived all mass extinctions since the Cambrian period. They capture prey with an adhesive ...net that is formed in a fraction of a second. The first naturalist to formally describe them was Lansdown Guilding (1797-1831), a British priest from the Caribbean island of Saint Vincent. His life is as little known as the history of the field he initiated, Onychophorology. This is the first general history of Onychophorology, which has been divided into half-century periods. The beginning, 1826-1879, was characterized by studies from former students of famous naturalists like Cuvier and von Baer. This generation included Milne-Edwards and Blanchard, and studies were done mostly in France, Britain, and Germany. In the 1880-1929 period, research was concentrated on anatomy, behavior, biogeography, and ecology; and it is in this period when Bouvier published his mammoth monograph. The next half-century, 1930-1979, was important for the discovery of Cambrian species; Vachon’s explanation of how ancient distribution defined the existence of two families; DNA and electron microscopy from Brazil; and primitive attempts at systematics using embryology or isolated anatomical characteristics. Finally, the 1980-2020 period, with research centered in Australia, Brazil, Costa Rica, and Germany, is marked by an evolutionary approach: from body and behavior to geographic distribution; the discovery of how they form their adhesive net; the reconstruction of Cambrian onychophoran communities, the first experimental taphonomy; the first country-wide map of conservation status (in Costa Rica); the first model of why they survive in cities; the discovery of new phenomena like food hiding, parental feeding investment, and ontogenetic diet shift; and the birth of a new research branch, onychophoran ethnobiology. While a few names often appear in the literature, most knowledge was produced by a mass of researchers who entered the field only briefly.
Abstract Sometimes, the editors of the large journals published in rich countries discriminate against the authors of tropical countries because of prejudice and not because of manuscript quality. ...Tropical researchers have two options: insist on publishing in these journals of the so called “Millionaire’s Club”, where there is often a natural disinterest in tropical issues; or to support the development of good tropical quality journals. The second option has ethical and practical advantages for everyone.
Polylactic acid (PLA) is widely used in tissue engineering and other biomedical applications. PLA can be modified with appropriate biocompatible ceramic materials since this would allow tailoring the ...mechanical properties of the tissues to be engineered. In this study, PLA-based non-woven fibrillar nanocomposites containing nanoparticles of hydroxyapatite (HA), a bioceramic commonly used in bone tissue engineering, were prepared via solution blow spinning (SBS). The compositions of the final materials were selected to study the influence of HA concentration on the structure, morphology, and thermal and mechanical properties. The resulting materials were highly porous and mainly constituted fibers. FTIR analysis did not reveal any specific interactions. The diameters of the fibers varied very little with the composition. For example, slightly thinner fibers were obtained for pure PLA and PLA + 10% HA, with fiber diameters of less than 400 nm, while the thicker fibers were found for PLA + 1% HA, with average diameters of 427 ± 170 nm. The crystallinity and stiffness of the PLA/HA composite increased with the HA content. Further, composites containing PLA fibers with slightly larger diameters were more ductile. Thus, with an appropriate balance between factors, such as the diameter of the solution-blow-spun PLA fibers, HA particle content, and degree of crystallinity, PLA/HA composites may be effectively used in tissue engineering applications.
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