Visibilidad de las publicaciones cubanas en el Indice Mexicano de Revistas Biomédicas Latinoamericanas

Popularity and visibility of Serial Cuban publication´s in the Mexican Index of Latin American Biomedical Journals (IMBIOMED) are analyzed take into account some cibermetric indicators selected to fulfill this purpose. The countries with the greater contributions to IMBIOMED, the most discussed subjects and the number of website visits from 1999 to 2004 as well as its distribution, the most productive authors, the most frecuency read and downloaded article among others were determined. Aimed at determining the most popular Cuban journals a general index was develop according to position of each serial publication according to individual indicators. IMBIOMED processes 98 biomedical serial publications from 9 countries among then Cuba and Mexico having 58 and 29 respectively were the best represented. Among the 36 specialties treated in IMBIOMED the most important were General Medicine, Pediatrics, Neurology, odontology and Oncology. The Cuban journal´s of pediatrics, obstetrics and gynecology, General Integral Medicine were the most frecuently downloded in the research period. Acta Medica presented the highest download average according to proccesed article (24.5). The Revista Cubana de Obstetricia y Ginecología and the Revista Cubana de Pediatría reached the highest popularity indexes. IMBIOMED is a valuable tool for professionals of Latin America. The spread of its documental coverage facilitates the use of Latin American medical and scientific production as well as the assessment of visibility and popularity of biomedical journals of this region according to cibermetric indicators

Effects of size on the spectrum and stability of a confined on-center Hydrogen atom

In this work we studied the problem of the stability of confined atoms when they are released from confinement. We analyzed the confined Hydrogen atom inside a cage modelled by a square-well potential, in particular the effects of size on the energy and the electronic structure of the confined atom, by considering different internal radii of the confining cage. Starting from the confined wave function, we clarified the effect on the probability transition between different confined states, and characterized the stability of the atom when released from in term of both, the ionization probability and the transition probability to a bound state of the free atom. The values of the different atomic properties calculated present oscillations when they are studied as a function of the size of the confining cage. This behaviour can be explained in terms of the shell structure of the atom

Ionization probability of the hydrogen atom suddenly released from confinement

The problem of the stability of a confined atom when it is extracted from the confining cavity has been investigated, modeled by a spherical hard wall potential. The ionization probability when the atom is released from confinement has been obtained. The dependence of the ionization probability on the confinement radius and on the quantum numbers of the initial confined state has been studied. The probability density function of the ionization energy of the ejected electron has been obtained for the different cases considered. The oscillatory structure of this distribution function, with a principal maximum located in the neighborhood of the energy of the initial state and minima very close to zero has been elucidated. The sudden approximation has been applied and the analytic continuation method has been used to calculate the different stationary states

Ionization and excitation probabilities of a hydrogen atom suddenly released from penetrable confinement

The problem of the stability of the hydrogen atom when it is released from a confining environment is studied. The stability is analysed in terms of excitation and ionization probabilities of the final state for different initial states. A spherical confining cavity of finite barrier height v0 with inner radius r0 and thickness _ with the nuclear position at its center has been considered. The ionization probability presents different sharply peaked, non-symmetric local maxima as a function of the confinement size. This behaviour is related to the energy of the initial confined state that presents several maxima and minima in a kink-like structure as a function of the confinement size. The physical origin of these effects has been explained in terms of tunnelling and re-tunnelling of the atomic states. The sudden approximation and the analytic continuation method have been employed

Role of endogenous cannabinoids in the control of basal ganglia activity

The cannabinoid system is a novel intercellular signaling system that plays a prominent role, among others, in the control of basal ganglia function. This finding can be concluded from the data obtained in different series of anatomical, biochemical, electrophysiological and pharmacological studies. These data demonstrated: (i) that the basal ganglia contain high levels of endocannabinoids and their receptors, mainly including the cannabinoid CB1 receptor subtype but also a related receptor type, the vanilloid TRPV1 receptor; (ii) that the activation or the blockade of this system produces important changes in motor behavior, changes that are originated as a consequence of interactions of the cannabinoid system with various classic neurotransmitters such as GABA, dopamine or glutamate; and (iii) the occurrence of marked changes in specific elements of the cannabinoid signaling system in various basal ganglia disorders, with emphasis in the induction/upregulation of the cannabinoid CB2 receptor subtype. This large evidence relating endocannabinoids and their receptors to the function of the basal ganglia, both in the healthy and the pathological brain, has provided support for the idea that cannabinoid-based medicines, with selectivity for different targets of the cannabinoid signaling system (synthetic enzymes, receptors, inactivation system), might have therapeutic potential to alleviate symptoms and/or provide neuroprotection in basal ganglia disorders, in particular Parkinson´s disease and Huntington´s chorea. The present chapter will review the knowledge on this issue trying to establish the future lines for the research on the therapeutic potential of the cannabinoid signaling system in basal ganglia disorders.peer-reviewe

Comparison of micronuclei frequency in bone marrow cells of three rat lines

The aim of this paper is to compare the spontaneous and induced with cyclophosphamide micronucleus indexes in bone marrow cells of the Sprague Dawley, Lewis and Wistar rat lines. Five experimental groups were formed (10 animals of each sex and of each line, in every group). The first group was used as the negative control (intact animals), the second one was exposed to oral administration of drugs; other conditions were the same as for the other groups. The third group was treated with 2 % Tween 65 and the fourth group was treated with 0.9 % NaCl. Both substances were administered by oral way to 2 ml/kg during 14 days. The fifth group was treated intraperitoneally with strong mutagen cyclophosphamide in the dose of 50 mg/kg (10 ml/kg in solution), on 48th and 24th hours before euthanasia. The Sprague Dawley line (both sexes) was significantly different from the other lines. Rats of this line had lower index of spontaneous formation of micronuclei, higher index of cyclophosphamide­induced micronucle formation, percent of micronucleated erythrocytes in bone marrow and the index of cytotoxicity. The results obtained make it possible to identify the most appropriate line of rats as model animals for studies of genotoxicity. It will allow also to obtain more accurate estimates of genotoxicity of various substances.Сравнивали спонтанные и индуцированные циклофосфамидом микроядерные индексы в клетках костного мозга трех линий крыс – Sprague Dawley, Льюис и Вистар. Сформировали пять экспериментальных групп (по 10 животных каждого пола и линии в каждой группе). Первую группу использовали в качестве негативного контроля (интактные животные), вторая служила контролем влияния перорального приема препаратов. Все условия содержания были одинаковыми для всех групп животных. Крыс третьей группы обрабатывали 2 % Tween 65, а четвертой группы – 0,9 % NaCl. Оба вещества вводили перорально в дозе 2 мл/кг в течение 14 дней. Животных пятой группы обрабатывали внутрибрюшинно циклофосфамидом в дозе 50 мг/кг (10 мл/кг раствора), за 48 и 24 ч до эвтаназии. Линия Sprague Dawley (оба пола) существенно отличается от других. Крысы этой линии имели низкие показатели спонтанного образования микроядер и высокий индекс при индукции циклофосфамидом, а также процент эритроцитов с микроядрами в костном мозге и индекс цитотоксичности. Полученные результаты позволяют определить наиболее подходящие линии крыс в качестве модельных животных для изучения генотоксичности. Это также позволит получать более точные оценки генотоксичности различных веществ. Порівнювали спонтанні та індуковані циклофосфамідом мікроядерні індекси в клітинах кісткового мозку трьох ліній щурів – Sprague Dawley, Люіс і Вистар.Сформували п’ять експериментальних груп (по 10 тварин кожної статі і лінії в кожній групі). Першу групу використали як негативний контроль (інтактні тварини), друга слугувала контролем впливу перорального прийому препаратів. Всі умови утримання були однаковими для всіх груп тварин. Щурів третьої групи обробляли 2 % Тween 65, а четвертої групи – 0,9 % NaCl. Обидві речовини вводили перорально в дозі 2 мл/кг впродовж 14 днів. Тварин п’ятої групи обробляли внутрішньочеревно циклофосфамідом в дозі 50 мг/кг (10 мл/кг розчину), за 48 і 24 год до евтаназії. Лінія Sprague Dawley (обидві статі) істотно відрізнялась від інших. Щури цієї лінії мали низькі показники спонтанного утворення мікроядер і високий індекс при індукції циклофосфамідом, а також відсоток еритроцитів з мікроядрами в кістковому мозку та індекс цитотоксичності. Отримані результати дозволяють визначити найбільш відповідні лінії щурів як модельних тварин для вивчення генотоксичності. Це також дозволить отримувати точніші оцінки генотоксичності різних речовин

On- and off-center helium atom in a spherical multilayer quantum dot with parabolic confinement

The ground state energy of a helium atom inside a spherical multilayer quantum dot as a function of the atomic impurity location inside the quantum dot has been calculated. The multilayer quantum dot is modeled by a core/shell/well/shell structure using a parabolic confinement. The Configuration Interaction method and the Diffusion Monte Carlo have been used to solve the Schrödinger equation. Results obtained showed that the lowest energy configuration depends on the size of the different layers of the quantum dot and agreement between Configuration Interaction and Diffusion Monte Carlo results indicates that the Configuration Interaction approach used here would be suitable to compute excited states of this system

Pesticide evaluation in water, sediment and in oyster shells (Crassostrea rhizophorae) in the Manzanillo- Niquero coastal area, Cuba

Occasionally pesticides have been used excessively for the pest control in agriculture, and many of these compounds become toxic for living organisms, including man. Adjacent lands to Guacanayabo gulf, Cuba, show an important use in agriculture, mainly in rice due to the contribution of fluvial waters from several hydrographical basins. The coastal area from Manzanillo to Niquero, Granma province, is the habitat of commercial shrimps, oysters and fish. The objective of the study was to determine in that region the presence of chemical residues from pesticides in the waters, sediments and shells of the mangrove oyster Crassostrea rhizophorae, Guilding (1828), as indicators of contamination. Samplings were carried out in maximum rainfall months. Besides samples for pesticide determination by gas chromatography, hydrology was studied, and there were carried out surveys (85 farmers) to know about pesticide types, dose and application frequency per crop, for conceptual analysis of the study objective. Results indicate a non-affectation by chemical residues of pesticides in any of the evaluated matrixes; and satisfactory quality of the waters for fishing use according to the used hydrological indicators. Ignorance exists on the farmer part on the application and dose of these chemical products, and recommendations are offered on pesticide use to prevent future impacts on the ecosystems