Changes in blood parameters of hybrid tambacu fish parasitized by Dolops carvalhoi (Crustacea, Branchiura), a fish louse

Measurement of blood parameters has been used for many years as a tool for monitoring the health offish. The present study investigated the effects of a natural infestation of Dolops carvalhoi Lemos de Castro, 1949, on red blood cells, thrombocytes and white blood cell counts, as well as plasma glucose and serum electrolyte levels in hybrid tambacu (Piaractus mesopotamicus × Colossoma macropomum). Parasitized fish showed low haematocrit and magnesium levels and increases in MCHC, plasma glucose levels, serum protein, sodium and chloride levels, number of monocytes and PAS-positive granular leukocytes (PAS-GL), when compared with values in control fish. This study is the first to report changes in fish physiology caused by D. carvalhoi infestation, and the results obtained indicate that a mild infection can lead to important osmoregulatory disturbances in hosts.

Morphologic changes and the expression of alpha-melanocyte stimulating hormone and melanocortin-1 receptor in melasma lesions: A comparative study

Melasma is a common acquired symmetrical hypermelanosis characterized by irregular light- to dark-brown macules on sun-exposed skin areas. The literature shows few studies on its physiopathogeny. However, changes in α-melanocyte stimulating hormone (α-MSH) secretion and melanocortin-1 receptor (MC1-R) expression may play a role to trigger this condition. Biopsies were taken from both melasma skin and adjacent perilesional normal skin of 44 patients. The biopsies were submitted for hematoxylin and eosin and Fontana-Masson staining and immunohistochemistry with Melan-A, α-MSH, and MC1-R, and processed for transmission electron microscopy. In some cases, they were submitted to MC1-R gene expression analysis by real-time polymerase chain reaction. Increased lymphohistiocytic infiltrate and solar elastosis, higher epidermal melanin were observed in melasma skin. Electron microscopy revealed a greater number of mature melanosomes in keratinocytes and melanocytes, and more prominent cytoplasmic organelles in melasma skin. There was no difference in melanocyte number between areas. However, melanocytes were larger and more dendritic in melasma skin. Immunohistochemistry with α-MSH and MC1-R showed significant labeling in melasmic epidermis but MC1-R messenger ribonucleic acid (RNAm) did not show significant quantitative difference between melasma and normal skin. © 2010 by Lippincott Williams & Wilkins.

Food selection by a mangrove crab: Temporal changes in fasted animals

The feeding choices of the mangrove crab Ucides cordatus for various mangrove plant leaves (Avicennia schaueriana, Laguncularia racemosa, and Rhizophora mangle) at different ages (mature, senescent pre-abscission, and decomposing leaves) were examined. In a controlled experiment set in a mangrove area, we evaluated crab selection for different plant leaves by analyzing foraging rate (number of leaves with predation marks) and leaf consumption. Crabs were housed individually in plastic containers and after a 3-day fast supplied with leaf fragments every 24 h for 72 h. Uneaten leaves were removed before each new food offering. No food selection was observed in the first day, but after this period, senescent leaves, which have a high polyphenol content, were rejected. On the third day, an interactive effect between plant species and leaf age was shown to affect leaf selection, with mature leaves of A. schaueriana and L. racemosa being more selected than the other treatments. This observation was consistent across crab sexes and ages. Our results show that food selection by this mangrove crab changes through time in fasted animals, suggesting that this variable must be controlled in food preference studies. © 2012 Springer Science+Business Media B.V.

The Number of Bleaching Sessions Influences Pulp Tissue Damage in Rat Teeth

Introduction: Hydrogen peroxide tooth bleaching is claimed to cause alterations in dental tissue structures. This study investigated the influence of the number of bleaching sessions on pulp tissue in rats. Methods: Male Wistar rats were studied in 5 groups (groups 1S-5S) of 10 each, which differed by the number (1-5) of bleaching sessions. In each session, the animals were anesthetized, and 35% hydrogen peroxide gel was applied to 3 upper right molars. Two days after the experimental period, the animals were killed, and their jaws were processed for light microscope evaluation. Pulp tissue reactions were scored as follows: 1, no or few inflammatory cells and no reaction; 2, <25 cells and a mild reaction; 3, between 25 and 125 cells and a moderate reaction; and 4, 125 or more cells and a severe reaction. Results from each experimental group were compared between groups and within groups to the corresponding unbleached upper left molars and analyzed for significant differences using the Kruskal-Wallis test (P < .05). Results: All tissue sections showed significant bleaching-induced changes in the dental pulp. After 1 bleaching session, necrotic tissue in the pulp horns and underlying inflammatory changes were observed. The extent and intensity of these changes increased with the number of bleaching sessions. After 5 sessions, the changes included necrotic areas in the pulp tissue involving the second third of the radicular pulp and intense inflammation in the apical third. Conclusions: The number of bleaching sessions directly influenced the extent of pulp damage. © 2013 American Association of Endodontists.

Modular Hyperthermostable Bacterial Endo-beta-1, 4-Mannanase: Molecular Shape, Flexibility and Temperature-Dependent Conformational Changes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Positioning and number of nutritional levels in dose-response trials to estimate the optimal-level and the adjustment of the models

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Hematological and biochemical changes in a Phrynops geoffroanus (Schweigger, 1812) population in response to environmental stressors

Turtles are among the most endangered vertebrate groups, and the main threats to populations are environmental pollution and habitat degradation. The species Phrynops geoffroanus, popularly known as “Geoffroy’s side-necked turtle”, has proliferated in polluted environments, where adverse conditions could influence their living habits and physiological condition. Studies that monitor the effects of environmental pollution are key to understanding the species’ biology and designing effective conservation strategies. Thus, the analysis of hematological and biochemical parameters has been shown to be important in assessing the health of wild animals and risks for the animal and ecosystem. This study aimed to assess the environmental influence on the physiology of a P. geoffroanus population through the evaluation of antioxidant status and responses to environmental stressors, compared to specimens from a place under controlled conditions. Blood samples of 60 specimens were collected, 30 from the Felicidade Stream, polluted environment, within the city of São José do Rio Preto, and 30 from the “Reginaldo Uvo Leone” breeding farm, Tabapuã, SP, a place under controlled conditions, whose samples constituted the control group. They were evaluated by hemogram and by determining thiobarbituric acid reactive species (TBARS), Trolox-equivalent antioxidant capacity (TEAC) and the activities of the antioxidant enzymes catalase and glucose-6-phosphate dehydrogenase (G6PDH). There was a wide variation in hematological parameters of P. geoffroanus from the urban environment. The red blood cell count and hemoglobin values were significantly less than those observed in animals from the breeding farm (P = 0.0004; P = 0.0371, respectively). There was a significant increase in the number of thrombocytes (P < 0.0001) and leukocytes (P < 0.0001) in the animals from Felicidade Stream. The stress indices were similar between the two groups (P = 0.4077). TBARS levels showed the cytotoxic potential of compounds in the urban environment, whose animals had elevated levels of lipid peroxidation (P < 0.0001), despite showing a response to environmental damages with increase in antioxidant capacity, as demonstrated by the TEAC assay (P = 0.0207). The lower catalase enzyme activity noted in individuals from the urban environment (P = 0.000184) could be due to the presence of inhibitory compounds. On the other hand, G6PDH activity was higher (P = 0.002962), where this enzyme acts in the generation of NADPH, which is used in several detoxification pathways. We conclude that environmental contamination can increase oxidative damages and generate physiological changes in this species. These data are very useful for the conservation of P. geoffroanus and turtles in general, and confirm that these techniques are effective in monitoring natural regions and that P. geoffroanus can serve as an environmental contamination bioindicator.

Morphological changes of mammalian nucleoli during spermatogenesis and their possible role in the chromatoid body assembling

Chromatoid body (CB) is a typical cytoplasmic organelle of germ cells, and it seems to be involved in RNA/protein accumulation for later germ-cell differentiation. Despite most of the events in mammals spermatogenesis had been widely described in the past decades and the increase in the studies related to the CB molecular composition and physiology, the origins and functions of this important structure of male germ cells are still unclear. The aims of this study were to describe the nucleolar cycle and also to find some relationship between the nucleolar organization and the CB assembling during the spermatogenesis in mammals. Cytochemical and cytogenetics analysis showed nucleolar fragmentation in post-pachytene spermatocytes and nucleolar reorganization in post-meiotic spermatids. Significant difference in the number and in the size of nucleoli between spermatogonia and round spermatids, as well as differences in the nucleolar position within the nucleus were also observed. Ultrastructural analysis showed the CB assembling in the cytoplasm of primary spermatocytes and the nucleolar fragmentation occurring at the same time. In conclusion our results suggest that the CB may play important roles during the spermatogenesis process in mammals and that its origin may be related to the nucleolar cycle during the meiotic cell cycle.

Alloxan-Induced Diabetes Causes Morphological and Ultrastructural Changes in Rat Liver that Resemble the Natural History of Chronic Fatty Liver Disease in Humans

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

FIPRONIL promotes motor and behavioral changes in honey bees (APIS Mellifera) and affects the development of colonies exposed to sublethal doses

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Changes in the phytoplankton structure downstream a large reservoir: effects of tributaries on the assemblages attributes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Changes in maternal body composition and metabolism of dairy goats during pregnancy

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Temporal changes in calcium-binding proteins in the medial geniculate nucleus of the monkey Sapajus apella

The subdivisions of the medial geniculate complex can be distinguished based on the immunostaining of calcium-binding proteins and by the properties of the neurons within each subdivision. The possibility of changes in neurochemistry in this and other central auditory areas are important aspects to understand the basis that contributing to functional variations determined by environmental cycles or the animal's cycles of activity and rest. This study investigated, for the first time, day/night differences in the amounts of parvalbumin-, calretinin- and calbindin-containing neurons in the thalamic auditory center of a non-human primate, Sapajus apella. The immunoreactivity of the PV-IR, CB-IR and CR-IR neurons demonstrated different distribution patterns among the subdivisions of the medial geniculate. Moreover, a high number of CB- and CR-IR neurons were found during day, whereas PV-IR was predominant at night. We conclude that in addition to the chemical heterogeneity of the medial geniculate nucleus with respect to the expression of calcium-binding proteins, expression also varied relative to periods of light and darkness, which may be important for a possible functional adaptation of central auditory areas to environmental changes and thus ensure the survival and development of several related functions.

Statistical detection of spurious variations in daily raingauge data caused by changes in observation practices, as applied to records from various parts of the world

In the instrumental records of daily precipitation, we often encounter one or more periods in which values below some threshold were not registered. Such periods, besides lacking small values, also have a large number of dry days. Their cumulative distribution function is shifted to the right in relation to that for other portions of the record having more reliable observations. Such problems are examined in this work, based mostly on the two-sample Kolmogorov–Smirnov (KS) test, where the portion of the series with more number of dry days is compared with the portion with less number of dry days. Another relatively common problem in daily rainfall data is the prevalence of integers either throughout the period of record or in some part of it, likely resulting from truncation during data compilation prior to archiving or by coarse rounding of daily readings by observers. This problem is identified by simple calculation of the proportion of integers in the series, taking the expected proportion as 10%. The above two procedures were applied to the daily rainfall data sets from the European Climate Assessment (ECA), Southeast Asian Climate Assessment (SACA), and Brazilian Water Resources Agency (BRA). Taking the statistic D of the KS test >0.15 and the corresponding p-value <0.001 as the condition to classify a given series as suspicious, the proportions of the ECA, SACA, and BRA series falling into this category are, respectively, 34.5%, 54.3%, and 62.5%. With relation to coarse rounding problem, the proportions of series exceeding twice the 10% reference level are 3%, 60%, and 43% for the ECA, SACA, and BRA data sets, respectively. A simple way to visualize the two problems addressed here is by plotting the time series of daily rainfall for a limited range, for instance, 0–10 mm day−1.