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51.
Milena Rychnovská-Soudková 《Biologia Plantarum》1963,5(2):175-180
Jedním z kritérií pro posuzování odolnosti rostiin v??i suchu je jejich schopnost sná?et vodní deficit ani? nastanou irreversibilní změny v jejich pletivech. Tato schopnost byla zkoumána metodikou, popsanou v p?edlo?ené práci. Listy některých xerothermních trav (druhy roduStipa, Melica atd.) vysýchaly za p?esně definovaných pokusných podmínek tak, ?e dosáhly r?zně odstupňovaného vodního deficitu. Potom byly roz?ezány na segmenty a ve speciálním ráme?ku dosycovány vodou. P?vodní deficit i jeho vyronání bylo sledvváno váhově. Výsledné hodnoty byly znázorněny graficky. Zatímco ztráta vody z list? během vysýchání probíhala v některých p?ípadech lineárně, k?ivka dosycování ukazovala charakteristický zlom, který indikoval, jak dalece byla ztráta vody nahraditelná, a kdy do?lo ji? k irreversibilním změnám. Ukázalo se, ?e ze studované série rostlin druhy typicky kontinentální mají schopnost doplňovat svou zásobu vody ad integrum i p?i zna?ném vodním deficitu. Rostliny s areálem spí? oceánického charakteru tuto schopnost nemají. Je pravděpodobné, ?e i tato vlastnost bude směrodatná p?i výkladu kausální fytogeografie. 相似文献
52.
Yahya Sohrabi Helena Havelková Tetyana Kobets Matyá? ?íma Valeriya Volkova Igor Grekov Ta?ána Jaro?íková Iryna Kurey Jarmila Vojtí?ková Milena Svobodová Peter Demant Marie Lipoldová 《PLoS neglected tropical diseases》2013,7(7)
Background
L. tropica can cause both cutaneous and visceral leishmaniasis in humans. Although the L. tropica-induced cutaneous disease has been long known, its potential to visceralize in humans was recognized only recently. As nothing is known about the genetics of host responses to this infection and their clinical impact, we developed an informative animal model. We described previously that the recombinant congenic strain CcS-16 carrying 12.5% genes from the resistant parental strain STS/A and 87.5% genes from the susceptible strain BALB/c is more susceptible to L. tropica than BALB/c. We used these strains to map and functionally characterize the gene-loci regulating the immune responses and pathology.Methods
We analyzed genetics of response to L. tropica in infected F2 hybrids between BALB/c×CcS-16. CcS-16 strain carries STS-derived segments on nine chromosomes. We genotyped these segments in the F2 hybrid mice and tested their linkage with pathological changes and systemic immune responses.Principal Findings
We mapped 8 Ltr (Leishmania tropica response) loci. Four loci (Ltr2, Ltr3, Ltr6 and Ltr8) exhibit independent responses to L. tropica, while Ltr1, Ltr4, Ltr5 and Ltr7 were detected only in gene-gene interactions with other Ltr loci. Ltr3 exhibits the recently discovered phenomenon of transgenerational parental effect on parasite numbers in spleen. The most precise mapping (4.07 Mb) was achieved for Ltr1 (chr.2), which controls parasite numbers in lymph nodes. Five Ltr loci co-localize with loci controlling susceptibility to L. major, three are likely L. tropica specific. Individual Ltr loci affect different subsets of responses, exhibit organ specific effects and a separate control of parasite load and organ pathology.Conclusion
We present the first identification of genetic loci controlling susceptibility to L. tropica. The different combinations of alleles controlling various symptoms of the disease likely co-determine different manifestations of disease induced by the same pathogen in individual mice. 相似文献53.
Anders West Poul Jennum Sofie Amalie Simonsen Birgit Sander Milena Pavlova Helle K. Iversen 《Chronobiology international》2017,34(6):687-697
Introduction and rationale: Stroke is a major cause of acquired cerebral disability among adults, frequently accompanied by depression, anxiety, cognitive impairment, disrupted sleep and fatigue. New ways of intervention to prevent these complications are therefore needed. The major circadian regulator, the suprachiasmatic nucleus, is mainly controlled by natural daylight, and the blue spectrum is considered the most powerful. During stroke rehabilitation, patients typically are mostly indoors and therefore not exposed to the natural daytime variation in light intensity. Furthermore, several rehabilitation hospitals may be exposed to powerful light in the blue spectrum, but at a time that is adversely related to their endogenous circadian phase, for example in the late evening instead of the daytime. Hypothesis: Naturalistic light that mimics the natural daytime spectrum variation will have a positive impact on the health of poststroke patients admitted to rehabilitation. We test specifically for improved sleep and less fatigue (questionnaires, polysomnography, Actiwatch), improved well-being (questionnaires), lessen anxiety and depression (questionnaires), improved cognition (tests), stabilizing of the autonomous nervous system (ECG/HR, blood pressure, temperature) and stabilizing of the diurnal biochemistry (blood markers). Study design: The study is a prospective parallel longitudinal randomized controlled study (quasi randomization). Stroke patients in need of rehabilitation will be included at the acute stroke unit and randomized to either the intervention unit (naturalistic lighting) or the control unit (CU) (standard lighting). The naturalistic light is installed in the entire IU (Cromaviso, Denmark). Conclusion: This study aims to elucidate the influence of naturalistic light on patients during long-term hospitalization in a real hospital setting. The hypotheses are based on preclinical research, as studies using naturalistic light have never been performed before. Investigating the effects of naturalistic light in a clinical setting is therefore much needed. 相似文献
54.
55.
Depaquit J Ferté H Léger N Lefranc F Alves-Pires C Hanafi H Maroli M Morillas-Marquez F Rioux JA Svobodova M Volf P 《International journal for parasitology》2002,32(9):1123-1131
An intraspecific study on Phlebotomus sergenti, the main and only proven vector of Leishmania tropica among the members of the subgenus Paraphlebotomus was performed. The internal transcribed spacer 2 (ITS2) sequences of 12 populations from 10 countries (Cyprus, Egypt, Italy, Lebanon, Morocco, Pakistan, Portugal, Spain, Syria, and Turkey) were compared. Samples also included three species closely related to P. sergenti: Phlebotomus similis (three populations from Greece and Malta), Phlebotomus jacusieli and Phlebotomus kazeruni. Our results confirm the validity of the taxa morphologically characterised, and imply the revision of their distribution areas, which are explained through biogeographical events. At the Miocene time, a migration route, north of the Paratethys sea would have been followed by P. similis to colonise the north of the Caucasus, Crimea, Balkans including Greece and its islands, and western Turkey. Phlebotomus sergenti would have followed an Asiatic dispersion as well as a western migration route south of the Tethys sea to colonise North Africa and western Europe. This hypothesis seems to be well supported by high degree of variation observed in the present study, which is not related to colonisation or to intra-populational variation. Two groups can be individualised, one oriental and one western in connection with ecology, host preferences and distribution of L. tropica. We hypothesise that they could be correlated with differences in vectorial capacities. 相似文献
56.
Jimmy?Cabra-GarcíaEmail author Christian?Bermúdez-Rivas Ana?Milena?Osorio Patricia?Chacón 《Biodiversity and Conservation》2012,21(6):1493-1508
In this study α and β diversity patterns of five leaf litter arthropod groups (ants, predatory ants, oribatid mites, spiders
and other arachnids) were described and compared in 39 sampling patches of a transformed landscape in southwestern Colombia,
that represented five vegetation types: secondary forest, riparian forest, giant bamboo forest, pasture and sugarcane crop.
It was also assessed whether some taxa could be used as diversity surrogates. A total of 6,765 individuals grouped in 290
morphospecies were collected. Species richness in all groups was lower in highly transformed vegetation types (pasture, sugarcane
crop) than in native ones (forests). In contrast, there were no clear tendencies of β diversity among vegetation types. Considering
sampling patches, 0.1–42% of the variation in α diversity of one taxonomic group could be explained from the α diversity of
another, and 0.2–33% of the variation of β diversity of a given taxon was explained by that in other groups. Contrary to recent
findings, we concluded that patterns of α diversity are more congruent than patterns of β diversity. This fact could be attributed
to a sampling effect that promotes congruence in α diversity and to a lack of a clear regional ecological gradient that could
promote congruent patterns of β diversity. We did not find evidence for an ideal diversity surrogate although diversity patterns
of predatory ants had the greatest congruencies. These results support earlier multi-taxon evaluations in that conservation
planning should not be based on only one leaf litter arthropod group. 相似文献
57.
Milena S. Espíndola Leonardo J. G. Lima Luana S. Soares Maira C. Cacemiro Fabiana A. Zambuzi Matheus de Souza Gomes Laurence R. Amaral Valdes R. Bollela Olindo A. Martins-Filho Fabiani G. Frantz 《PloS one》2015,10(12)
Background
Successful highly active antiretroviral therapy (HAART) has changed the outcome of AIDS patients worldwide because the complete suppression of viremia improves health and prolongs life expectancy of HIV-1+ patients. However, little attention has been given to the immunological profile of patients under distinct HAART regimens. This work aimed to investigate the differences in the immunological pattern of HIV-1+ patients under the first- or second-line HAART in Brazil.Methods
CD4+ T cell counts, Viral load, and plasma concentration of sCD14, sCD163, MCP-1, RANTES, IP-10, IL-1β, IL-6, TNF-α, IL-12, IFN-α, IFN-γ, IL-4, IL-5, and IL-10 were assessed for immunological characterization of the following clinical groups: Non-infected individuals (NI; n = 66), HIV-1+ untreated (HIV; n = 46), HIV-1+ treated with first-line HAART (HAART 1; n = 15); and HIV-1+ treated with second-line HAART (HAART 2; n = 15).Results
We found that the immunological biosignature pattern of HAART 1 is similar to that of NI individuals, especially in patients presenting slow progression of the disease, while patients under HAART 2 remain in a moderate inflammatory state, which is similar to that of untreated HIV patients pattern. Network correlations revealed that differences in IP-10, TNF-α, IL-6, IFN-α, and IL-10 interactions were primordial in HIV disease and treatment. Heat map and decision tree analysis identified that IP-10>TNF-α>IFN-α were the best respective HAART segregation biomarkers.Conclusion
HIV patients in different HAART regimens develop distinct immunological biosignature, introducing a novel perspective into disease outcome and potential new therapies that consider HAART patients as a heterogeneous group. 相似文献58.
59.
Phenolic acids were separated into three fractions and determined by HPLC inMedicago sativa callus culture at the age of two, three and four weeks. The contents of free and especially of predominating ester-bound
phenolic acids decreased with callus age to approx. 80 % while the content of phenolic acids nonextractable by methanol increased
byca. 90 %. The proportion of benzoic acid derivatives rose from 15 to 21 % within four weeks. The determined difference in the
contents of phenolic acids in the upper and lower parts of callus diminished with age. The content of bound forms was higher
in the lower part regardless of the callus age. The content of free acids in two weeks old callus was half as high as in the
upper part. 相似文献
60.
Anna Corsini Milena Colombo Claudio Gardana Sarah Zecchin Paolo Simonetti Lucia Cavalca 《Annals of microbiology》2018,68(5):295-304
Achromobacter sp. strain N2 was isolated from a pyrite-cinder-contaminated soil and presented plant growth promoting traits (ACC deaminase activity, production of indole-3-acetic and jasmonic acids, siderophores secretion, and phosphate solubilization) and arsenic transformation abilities. Achromobacter sp. strain N2 was resistant to different metals and metalloids, including arsenate (100 mM) and arsenite (5 mM). The strain was resistant to ionic stressors (i.e., arsenate and NaCl), whereas bacterial growth was impaired by osmotic stress. Strain N2 was able to oxidize 1.0 mmol L?1 of arsenite to arsenate in 72 h. This evidence was supported by the retrieval of an arsenite oxidase AioA gene highly homologous to arsenite oxidases of Achromobacter and Alcaligenes species. Rice seeds of Oryza sativa (var. Loto) were bio-primed with ACCD-induced and non-induced cells in order to evaluate the effect of inoculation on rice seedlings growth and arsenic uptake. The bacterization with ACCD-induced cells significantly improved seed germination and seedling heights if compared with the seeds inoculated with non-induced cells and non-primed seeds. Enhanced arsenic uptake was evidenced in the presence of ACCD-induced cells, suggesting a role of ACCD activity on the mitigation of the toxicity of arsenic accumulated by the plant. This kind of responses should be taken into account when proposing PGP strains for improving plant growth in arsenic-rich soils. 相似文献