Miracle-dz/UniFAR-FTUs huggingface dataset:
Changes in Leaf Gas Exchange Properties of Cloned Betula pendula Saplings after Partial Defoliation

The effects of partial defoliation on the gas exchange characteristics of the remaining leaves were studied in cloned Betula pendula L. saplings grown in pots on two different soil types: prefertilized peat and unfertilized and (Experiment 1). The responses of undamaged leaves to different damage modes of leaf laminae were also studied using saplings grown on prefertilized peat only (Experiment 2). In Experiment 1, removal of the upper leaves, which represented about half the total leaf area, approximately doubled the mean net photosynthetic rates of the remaining lower leaves on both soil types and at both measuring dates (12-13 d and 34 d after assigning the treatments)
Degree-Day Models for Emergence and Development of the Rice Water Weevil (Coleoptera: Curculionidae) in Southwestern Louisiana

Abstract The rice water weevil, Lissorhoptrus oryzophilus Kuschel, is the most destructive insect pest of rice in the United States. Degree-day (DD) models were developed to predict the emergence date of adult rice water weevils from overwintering in the spring and to describe larval and pupal development on two varieties of rice under field conditions. The model that best described emergence of weevils from overwintering was derived from 14 yr of light trap captures. The temperature threshold for the best-fit model was 15.6°C, the start date for the model (date at which degree-day accumulation begins) was 33 d after 1 January, and the end point for the model was a cumulative light trap capture of six weevils. By using these parameters, emergence of weevils occurred after accumulation of 139.2 DD (°C × day). The model predicted emergence of weevils in 2001, 2002, 2003, and 2004 with an error of 4, 7, 1, and 2 d, respectively. For the model describing larval development, the number of degree-days required for development from egg to 50% pupation was 359.1 ± 19.4 DD (°C × day) with a low temperature threshold of 10°C. The number of degree-days required for pupal development was 264.3 DD (°C × day), and the total degree-days required for development of one generation was ≈623.4 DD (°C × day). Larval development did not differ on cultivars ‘Jefferson’ and ‘Bengal’.
Aspects cliniques des syndromes coronariens aigus

On distingue maintenant les syndromes coronariens aigus avec ou sans elevation (ou sus-decalage) du segment ST. Les premiers correspondent a une occlusion complete durable d’une artere coronaire et necessitent un traitement de desobstruction en urgence, par thrombolyse intraveineuse ou par angioplastie. Dans les syndromes coronariens aigus sans elevation du segment ST, la stratification du risque est un element fondamental de la prise en charge, permettant de distinguer les formes necessitant une exploration coronarographique precoce et celles dont le diagnostic reposera sur des examens non invasifs. Parmi les facteurs de mauvais pronostic, il faut retenir essentiellement la repetition des douleurs de repos, l’existence de modifications du segment ST sur l’electrocardiogramme et l’augmentation des marqueurs biologiques de necrose myocardique. Dans tous les types de syndromes coronariens aigus, un traitement de prevention secondaire est imperatif pour tenter de freiner l’evolution de la maladie atherosclereuse.
A RISK OF VISCERAL LEISHMANIASIS IN CASE OF HELMINTHS CO-INFECTION IN ENDEMIC REGIONS.

People in the endemic region are more prone to helminth infections due to the poor hygienic conditions and their genetic susceptibility may be a factor for Leishmania infection. The acute worm infections may not cause fatal outcome to host but it may facilitates the infection of other intracellular pathogens which cause higher rate of morbidity. In case of Leishmania donovani infection, helminth infections mainly elicit Th2 type protective host immune response characterized by secretion of IL-4, IL-13, IL-5, IL-9 and IL-10, which may suppress the Th1 protective host immune response. Pre-immune polarized (Th2/Th1) individuals due to the helminth infections and their recovery from infection after treatment may have higher levels of serum IL-4 and IL-13 are highly susceptible for visceral leishmaniasis in endemic regions. These Th2 type cytokines, IL-4, IL-13 and IL-10 have immunosuppressive activity, help in the parasite survival by inhibiting the macrophage induced IFN-γ production and oxidative burst mechanism, thereby enhancing disease progression in chronic visceral leishmaniasis. In addition, IL-5 dependent eosinophilia in helminth infections may cause inflammation in visceral organs leading to tissue damage hence these individuals might be susceptible for parasite attack. Therefore, we hypothesize that the Th2 type cytokine milieu of helminth infection might be increase rate of susceptibility to VL occurrence in endemic regions.
On seasonal fluctuations of available Olsen P in soils

The likelihood of a strong seasonal effect on the analytical results of soil chemical tests has been substantiated by several findings. The occurrence of such a trouble would heavily affect the routine work of chemical laboratories dealing with hundreds or thousands of soil samples every year and would possibly interfere even with current timing of soil sampling and testing in agronomical research. Soils from four different experimental fields were sampled and analyzed for Olsen P test through the growing season of both spring-summer crops (maize) and autumn-spring crops (soft wheat). To avoid the cross effect of recent P applications, samples were collected only from the control plots, with no P applied. In a first long-time experiment the level of Olsen P was followed in three soils during two years, while in a second experiment the study considered two different soils for a couple of years each. The amount of extractable (available) Olsen P showed significant fluctuations-with-time in four years out of six. The observed variations seems entirely due to P absorption by crops, as they appeared in the final samplings during the cropping season. The amount of decrease was nearly always small, less than 1-1.5 mg kg-1 soil, and consistent with the reduction of the available pool which is to be expected as crops gradually take up nutrients. As far as Olsen P is concerned, no evidence was found for the occurrence of erratic seasonal variations such as those previously reported. As soil samples for advisory purposes are usually taken at different times of the year, it seems reassuring that no complications are to be expected about information needed to interpret the results of chemical tests.
Genetic resistance to root-knot nematode (Meloidogyne javanica) in eggplant (Solanum melongena)

A germplasm collection of 39 eggplant Solanum melongena genotypes and one accession of S. torvum was evaluated for resistance to the root-knot nematode (Meloidogyne javanica) by using controlled greenhouse tests. Different degrees of resistance to the disease caused by this nematode species were observed among the genotypes tested. Complete resistance (no nematode egg mass formation up to 7 weeks after inoculation) was detected in one accession belonging to domesticated S. melongena species. Good levels of incomplete resistance were also observed in some commercial eggplant genotypes. This is apparently the first report of a source of complete resistance to M. javanica within the S. melongena gene pool and our finding could greatly facilitate the incorporation of this trait into commercial eggplant cultivars. S. torvum, previously described as resistant to several root-knot nematode species (including M. javanica, M. arenaria, and M. incognita) was also confirmed as a source of resistance to this Brazilian population of M. javanica. Therefore, S. torvum can be considered as one of the most promising sources of broad-spectrum resistance genes against root-knot nematodes. Broad-spectrum resistance is of paramount importance for breeding programmes focused on the development of cultivars for tropical and subtropical areas of the world where multiple infestation of soils with distinct Meloidogyne species is a very common feature.
The effect of polychlorinated biphenyls mixture (Aroclor 1254) on the embryonic development and hatching of Prussian carp, Carassius gibelio, and common carp, Cyprinus carpio (Actinopterygii: Cypriniformes: Cyprinidae)

Background. Polychlorinated biphenyls (PCBs) are persistent and bioacumulative chemical pollutants which exert negative physiological effects o n the reproductive system of mature male and female fish. PCBs present in the aquatic environment may also have an influence on developing embryos. The aim of this study was to inves- tigate the effect of Aroclor 1254, a polychlorinated biphenyls mixture, on the embryonic development of Prussian carp, Carassius gibelio (Bloch, 1782), and common carp, Cyprinus carpio L. Materials and methods. The samples of eggs obtained from 4 females of each species were divided into t wo dishes and incubated separately after fertilization (common carp) or activation (Prussian carp) with common carp sperm. The incubation, with Aroclor 1254 (1 or 10 ng · mL -1 ) or in water with no PCB added, lasted for 4 days. The mortality, hatching rate, number of hatched larvae, and number of deformed larvae were observed. Results. After 24 h of incubation of Prussian carp and common carp eggs there were no significant differences in the percentage of living eggs between t he Aroclor 1254 treated groups and the control one. The lowest tested concentration of PCB (1 ng · mL -1 ) accelerated the hatching of Prussian carp larvae at 75 h of incubation. The significant increase in the percentage of deformed larvae was observed only in the experiment with common carp eggs incubated with Aroclor 1254 at the concentration of 10 ng · mL -1 . Conclusion. Results of the presented data showed that Aroclor 1254 (at tested concentrations) is not harmful for the development of activated Prussian carp eggs but teratogenic effect was observed in the case of common carp embryos. K eywords: PCBs mixture, common carp, Prussian carp, embryonic development, reproduction
The use of Lawsonia inermis linn. (henna) in the management of burn wound infections

The effects of water and chloroform extracts of the leaves of Lawsonia inermis (henna plant) against the primary invaders of burnt wounds was investigated. Clinical isolates of Staphylococcus aureus, Streptococcus sp, Pseudemonas aeruginosa, Candida albicans, Fusarium oxysporum, and Aspergillus niger were treated with extracts of the leaves of L. inermis for antimicrobial activity using in vitro agar incorporation method and well diffusion methods respectively. The henna leaves extracts were able to inhibit the growth pattern of A. niger and F. oxysporum. Streptococcus sp. and S. aureus were also inhibited by the extracts. Inhibition of the microorganisms’ growth suggests that henna may be valuable in the management of burnt wound infections.
The kinetics and thermodynamics of polyglutamine aggregation

Protein misfolding as a result of polyglutamine (polyQ) repeat expansion plays a crucial role in the development a class of neurodegenerative disorders. These disorders are characterized by expansions in unique proteins, but share one common factor: polyQ repeat expansions beyond a pathological threshold, usually near 35 Glns. PolyQ containing peptides and proteins aggregate into amyloid-like fibrils, in both disease states and in vitro. While recent studies of simple polyQ aggregation have led to the development of a mechanism describing the fibril formation pathway, the kinetic and thermodynamic roles of even small modifications to the amino acid sequence are unclear. The goal of this work was to gain more specific information regarding the biophysical roles of terminal charge and Gln repeat length in the aggregation mechanism of simple polyQ peptides. We found that increases in both repeat length and attraction between terminal flanking sequences led to enhancements in fibril stability and spontaneous aggregation ability. In general, mutations in polyQ sequences that enhance their ability to assume a β-hairpin structure (the proposed building block of polyQ fibrils), and to associate with each other facilitate fibrillization through a nucleated polymerization pathway with a monomeric nucleus. The data discussed here have made significant contributions to our understanding of the basic aggregation properties of polyQ peptides, and have implications that can be directly translated to polyQ disease pathogenesis.
Cooperative Effects of STAT5 (Signal Transducer and Activator of Transcription 5) and C/EBP β (CCAAT/Enhancer-Binding Protein-β) onβ -Casein Gene Transcription Are Mediated by the Glucocorticoid Receptor

β-Casein gene transcription is controlled primarily by a composite response element (CoRE) that integrates signaling from the lactogenic hormones, PRL, insulin, and hydrocortisone, in mammary epithelial cells. This CoRE contains binding sites for STAT5 (signal transducer and activator of transcription 5) and C/EBPβ (CCAAT/enhancer-binding protein-β) and several half-sites for glucocorticoid receptor (GR). To examine how interactions among these three transcription factors might regulateβ -casein gene transcription, a COS cell reconstitution system was employed. Cooperative transactivation was observed when all three factors were expressed, but unexpectedly was not seen between STAT5 and C/EBPβ in the absence of full-length, transcriptionally active GR. Cooperativity required the amino-terminal transactivation domain of C/EBPβ, and neither C/EBPα nor C/EBPδ was able to substitute for C/EBPβ when cotransfected with STAT5 and GR. Different GR determinants were needed for transcriptional cooperation between S.
Is sperm really so cheap? Costs of reproduction in male adders, Vipera berus

Reproduction is energetically expensive for males as well as for females, but evolutionary biologists have typically regarded the energy costs of sperm production as trivial compared to the energy costs of overt reproductive behaviours, such as mate-searching, courtship, copulation and male–male combat. Adders (Vipera berus) offer an ideal model system in which to quantify the relative costs of spermatogenesis (and associated physiological preparations for reproductive activity) versus the costs of overt reproductive behaviours, because (i) these two activities occur sequentially rather than simultaneously, and are separated by a clear indicator (sloughing of the skin); and (ii) males do not feed during either of these phases. Hence, the rate of mass loss by males can be used as an index of energy costs. Surprisingly, the rate of mass loss is at least as high during the phase when males are immobile, building up sperm supplies, as when they move about and engage in reproductive behaviour. Rates of mass loss are not significantly correlated with male size or measures of the male's participation in reproductive activities. Our data suggest that sperm production may be a major energy cost to reproducing male adders, and that this species offers a useful system in which to further investigate this possibility.
CD3ε-mediated signals rescue the development of CD4+CD8+ thymocytes in RAG-2−/− mice in the absence of TCR β chain expression

Recent studies have shown that TCR beta chain expression can effect the differentiation of CD4-CD8- double-negative (DN) thymocytes to CD4+CD8+ double-positive (DP) thymocytes. The TCR beta chain is expressed on the surface of DP thymocytes in association with CD3 gamma, delta and epsilon chains, suggesting a potential role for CD3 components in this signaling process. We now report detection of a very low level of surface expression of CD3 epsilon on adult DN RAG-2-/- thymocytes. This surface CD3 epsilon was associated with CD3 gamma and delta chains, as detected by anti-CD3 epsilon immunoprecipitation analyses. Significantly, injection of anti-CD3 epsilon mAb into RAG-2-/- mice led to the accumulation of an IL-2R alpha- CD2+ DP cell population and a nearly 100-fold increase in thymic cellularity to essentially normal levels. Together, these data strongly indicate that TCR beta chain-mediated developmental signals are transduced by CD3 components and provide potential insights into mechanisms by which TCR beta chain expression may effect this process.
Regulatory T Cells and Cardiovascular Diseases

Recent researches have substantiated the active participation of chronic low-grade inflammation in cardiovascular disease where immune responses contribute to disease initiation and progression. Regulatory T cells (Tregs) are a unique lineage of T cells and have been proved to play a key role in controlling both the innate and adaptive immune responses under physiological and pathological conditions. Through suppression of immune system activation, Tregs are involved in tolerance to self antigens, thus maintaining immune homeostasis. Existence and function of Tregs were a matter of considerable debate over the last few decades, but owing to innovative molecular categorization of this specialized subpopulation of T cells, they have now been established as fundamental elements in the vertebrate immune system. In view of the prospective therapeutic avenues that Tregs may offer, we hereby review the current knowledge on the role of Tregs immunity in cardiovascular disease. [N A J Med Sci. 2011;4(4): 178-182 . ]
« Les lymphocytes : comment ça "Vav"? »

Les facteurs d’echange nucleotidique (GEF) de la famille Vav sont des activateurs essentiels des GTPases Rho qui controlent l’organisation du cytosquelette d’actine et la transcription de genes. Parmi les nombreux GEF identifies a ce jour, les proteines Vav sont les seules dont l’activite catalytique est reglee par phosphorylation sur tyrosine. En outre, leur structure faite de nombreux domaines d’interaction proteine-proteine et proteine-lipide leur permet de jouer un role adaptateur dans l’assemblage de complexes moleculaires. La combinaison unique de ces proprietes fait des proteines Vav un carrefour privilegie de multiples voies de signalisation dans de nombreux types cellulaires. La fonction des lymphocytes au cours des reponses immunitaire et inflammatoire met en jeu des remodelages extremement dynamiques de leur architecture cellulaire. Il n’est donc pas surprenant que les proteines Vav jouent un role central dans la regulation des reponses lymphocytaires physiologiques et pathologiques.
Darwin's Finches as Seed Predators and Dispersers

Abstract We investigated seed predation and dispersal by nine Darwin's finch (Geospizinae) species, including species previously regarded as seed predators or insectivores. All nine ate fruit. Eight commonly discarded seeds, acting as short-distance dispersers. Seven defecated viable seeds, being therefore potential longer-distance dispersers. Fruit comprised the majority of dietary items in all four Geospiza species and Small Tree Finch (Camarhynchus parvulus). All except Common Cactus Finch (G. scandens) defecated intact seeds. The highest proportions of feces containing viable seeds were of Small Ground Finch (G. fuliginosa) and the “insectivorous” species Woodpecker Finch (Camarhynchus pallidus) and Warbler Finch (Certhidea olivacea). These two may be more important endochorous dispersers than other species that eat more fruit but are better seed predators. Intact seeds were found in 23% of fecal samples; 50% of the samples with intact seeds had viable seeds. The most frequently encountered intact seeds were of the tiny-seeded, fleshy-fruited Miconia robinsoniana and a sedge, Kyllinga brevifolia. Dry fruit, such as sedges and grasses, were usually crushed but occasionally found intact in feces, and might frequently be dispersed long distances. Seeds of larger-seeded, fleshy-fruited species were often discarded, but may be commonly dispersed short distances. Dispersal of plants by finches is probably more common than suggested by their predominant feeding patterns of seed predation and insectivory, and rare long-distance dispersal could be important for plant evolution and spread of introduced plants in the Galapagos Islands.
Extended-spectrum plasmid-mediated β-lactamases

: Extended-spectrum beta-lactamases (ESBLs) are mutant enzymes which derive from TEM or SHV (class A) enzymes. They confer variable levels of resistance to cefotaxime, ceftazidime and other broad-spectrum cephalosporins and to monobactams such as aztreonam but have no detectable activity against cephamycins and carbapenems. Recently, new plasmid-mediated ESBLs, not derived from TEM or SHV enzymes but related to cephalosporinases of Enterobacteriaceae (class C enzymes), that confer resistance to all cephalosporins including cephamycins, have been reported. However, to date there have been no reported outbreaks due to strains producing transferable cephalosporinases. Klebsiella pneumoniae is the species in which the ESBL enzymes have been most commonly reported around the world. Most of the clinical isolates that produce TEM- or SHV-derived ESBL, come from hospitalised patients and have frequently caused nosocomial outbreaks. Care should be taken in the selection of a beta-lactam for the treatment of infections because the presence of an ESBL does not prevent other mechanisms of resistance, such as decreased permeability, from emerging. Broad-spectrum cephalosporins including cefepime and cefpirome are hydrolysed by ESBL. However, low level resistance to cefotaxime, ceftriaxone, cefepime and aztreonam does occur in some strains producing certain TEM-derived ESBL. It remains to be seen, therefore, whether such isolates are clinically susceptible to these drugs. The combination of a third-generation cephalosporin and a beta-lactamase inhibitor such as sulbactam could be of interest against some strains producing certain ESBLs. Among the 7-alpha-methoxy cephalosporins, cefotetan and latamoxef are the most active. However, cephamycins should be used with caution to treat infections caused by ESBL-producing K. pneumoniae because of the relative ease with which clinical strains decrease the expression of outer membrane proteins. The most active beta-lactams are the carbapenems, imipenem and meropenem, which are highly resistant to hydrolysis by TEM and SHV related beta-lactamases. Meropenem is intrinsically the more active agent, with MICs (0.03-0.12 mg/L) generally lower than those of imipenem (0.06-0.5 mg/L) and appears stable to all the beta-lactamases belonging to class A or C, including those with an extended-spectrum against third-generation cephalosporins.