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181.
Marília Lara Peixoto Leda Gonçalves Fernandes Matheus Araújo Cardoso Carvalho Milena Leite de Oliveira André Rodrigues dos Reis 《Biocontrol Science and Technology》2017,27(3):424-432
Agro-ecological diversification may increase natural biodiversity and decrease environmental impacts caused by the intensification of management practices, especially with respect to pest control. This study aimed to evaluate mite populations from surveys in commercial coffee (Coffea arabica) orchards managed in different ways. Four different cropping systems were compared: a conventional system (CS), non-pesticide system (NPS), organic system (OS) and organic agroforestry system (OAS). Mite samples were taken from 24 coffee plantations (n?=?6 for each management strategy). Six leaves per plant were collected from five sampling sites totalling 30 leaves from each plantation. Mites were removed from individual leaves, counted and identified to family level. Amongst the predatory mites, two families were detected; the Phytoseiidae was the most abundant family while the Stigmaeidae, generalist predatory mites, were only found in two management systems (NPS and AOS). Of the two families of phytophagous mites, the family Tenuipalpidae was the most abundant, but rarely found in AOS. The other phytophagous family, Tetranychidae, was less abundant in coffee crops than Tenuipalpidae, but the most abundant phytophagous family in CS. Understanding the relationship between mite populations and management practices can aid in choice of spraying strategies for different coffee management systems. 相似文献
182.
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
183.
Milena Damulewicz Agnieszka Loboda Alicja Jozkowicz Jozef Dulak Elzbieta Pyza 《Molecular neurobiology》2017,54(7):4953-4962
The Drosophila retina has an autonomous peripheral circadian clock in which the expression of the gene encoding heme oxygenase (HO) is under circadian control with the ho mRNA peaking at the beginning of the day and in the middle of the night. The function of HO in the retina is unknown, but we observed that it regulates the circadian clock and protects photoreceptors against DNA damage. The decline in HO level increases and decreases the expression of the canonical clock genes period (per) and Clock (Clk), respectively. The opposite result was observed after increasing HO expression. Among three products of HO activity—carbon monoxide (CO), ferrous ions, and biliverdin—the latter has no effect on per and Clk expressions, but CO exerts the same effect as the increase of ho expression. This suggests that HO action on the clock is mediated by CO, which may affect Clk expression during the day and the level of per expression. While ho expression is not stimulated by nitric oxide (NO), NO has the same effect on the clock as HO, increasing Clk expression and decreasing the expression of per. 相似文献
184.
Increased Chondrogenic Potential of Mesenchymal Cells From Adipose Tissue Versus Bone Marrow‐Derived Cells in Osteoarthritic In Vitro Models
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185.
Traykova-Brauch M Schönig K Greiner O Miloud T Jauch A Bode M Felsher DW Glick AB Kwiatkowski DJ Bujard H Horst J von Knebel Doeberitz M Niggli FK Kriz W Gröne HJ Koesters R 《Nature medicine》2008,14(9):979-984
We describe a transgenic mouse line, Pax8-rtTA, which, under control of the mouse Pax8 promoter, directs high levels of expression of the reverse tetracycline-dependent transactivator (rtTA) to all proximal and distal tubules and the entire collecting duct system of both embryonic and adult kidneys. Using crosses of Pax8-rtTA mice with tetracycline-responsive c-MYC mice, we established a new, inducible model of polycystic kidney disease that can mimic adult onset and that shows progression to renal malignant disease. When targeting the expression of transforming growth factor beta-1 to the kidney, we avoided early lethality by discontinuous treatment and successfully established an inducible model of renal fibrosis. Finally, a conditional knockout of the gene encoding tuberous sclerosis complex-1 was achieved, which resulted in the early outgrowth of giant polycystic kidneys reminiscent of autosomal recessive polycystic kidney disease. These experiments establish Pax8-rtTA mice as a powerful tool for modeling renal diseases in transgenic mice. 相似文献
186.
Recently Bulgarian Bone Marrow Donors Registry (BBMDR) has been established and since August 2005 it has been a member of
Bone Marrow Donors Worldwide. Currently the number of healthy donors included in the BBMDR is relatively low. All donors included
in the BBMDR are typed for HLA-A, -B, -DRB loci. Phylogenetic analysis based on HLA allele frequencies shows that Bulgarians
were characterized with closest genetic similarity to Macedonians, Greeks, Romanians, Cretans and Sardinians in comparison
to the other European and Mediterranean populations. On the contrary the second largest ethnic minority–the Roma were the
closest to the other Roma populations and North Indians. These differences were due to the predominance of alleles and haplotypes
that are specific for the Asian and the other Roma populations. These specific genetic profiles in the Bulgarian ethnic minorities
justify the need of an adequate representation of minorities in BBMDR. Future directions for BBMDR development are discussed,
including an increase of the total number of donors and these for ethnic minorities, as well the enhancement of the level
of resolution of the HLA typing for the donors in the registry. 相似文献
187.
In systems ranging from lakes and woodlands to coral reefs, the long-term ecosystem state may often be determined largely
by rare extreme events such as wet ENSO years, droughts, or disease outbreaks. Such events can flip these systems into a contrasting
state that represents either an alternative attractor or a transient that is slow enough to persist even if the frequency
of events that push the system to this state is low. Here we show that escape from herbivores is a mechanism that can play
a role in several state shifts of this kind. This can happen if plants become less susceptible to herbivory as they grow.
Using a model we show that, surprisingly, this mechanism can lead to a situation where a brief resource pulse for plants may
invoke a persistent shift to a high biomass state whereas gradual enrichment to the same resource level is insufficient to
allow such a change. This counterintuitive phenomenon occurs if the numerical response of herbivores is sufficiently slow
to allow the plants to use the resource pulse to escape to a safe biomass at which herbivory is reduced. Our results imply
that rates of environmental change can sometimes be more important than their magnitude. This has many ramifications. On the
conceptual side, our findings suggest that key mechanisms that regulate long-term ecosystem dynamics are easily missed by
the traditional focus of modelers on equilibria. A more practical corollary is that increased climatic variability may have
more profound effects in some ecosystems than gradual change in conditions. 相似文献
188.
Jeppe Reitan Andersen Imad Zein Gerhard Wenzel Birte Darnhofer Joachim Eder Milena Ouzunova Thomas Lübberstedt 《BMC plant biology》2008,8(1):2
Background
Forage quality of maize is influenced by both the content and structure of lignins in the cell wall. Biosynthesis of monolignols, constituting the complex structure of lignins, is catalyzed by enzymes in the phenylpropanoid pathway. 相似文献189.
Proteomic analysis of somatic embryogenesis in <Emphasis Type="Italic">Vitis vinifera</Emphasis> 总被引:1,自引:0,他引:1
Two dimensional gel electrophoresis coupled to mass spectrometry has been used to study the somatic embryogenesis in Vitis vinifera, by comparing embryogenic and non embryogenic calluses of the Thompson seedless cv. More than 1,000 spots were reproducibly resolved in colloidal Coomassie brilliant blue stained gels over a pI nonlinear range of 3–10 in the first dimension and using homogeneous 12.5% polyacrylamide gels in the second dimension. The
expression pattern of 35 spots differed significantly between the two samples. These spots were processed by mass spectrometry
analysis and the protein identity was assigned by using both the non-redundant protein and EST databases. Several responsive
proteins, some already known to be involved in the somatic embryogenesis process while others, for the first time put into
relation with this process, have been described. Moreover, they have been subdivided in functional categories, and their putative
role is discussed in terms of their relevance in the somatic embryogenesis process. 相似文献
190.
Autogenic succession, land-use change, and climatic influences on the Holocene development of a kettle-hole mire in Northern Poland 总被引:5,自引:0,他引:5
Mariusz Lamentowicz Milena Obremska Edward A.D. Mitchell 《Review of Palaeobotany and Palynology》2008,151(1-2):21-40
We reconstructed the Holocene developmental history of a kettle-hole peatland in the Tuchola Forest of Northern Poland, using pollen, testat amoebae and plant macrofossil indicators. Our aims were to determine the timing and pattern of autogenic succession and natural and anthropogenic influences on the peatland. Northern Poland is under mixed oceanic and continental climatic influences but has so far been less studied in a palaeoecological context than more oceanic regions of Europe. In the first terrestrial developmental phase of the mire, the testate amoebae-inferred depth to water table revealed two major dry shifts at ca. 9400 (end of lake phase) and ca. 7100 cal BP (a period of global cooling and dry shift in Western Europe). Conditions became wetter again in two steps at ca. 6700 and ca. 5800 BP after a dry event at ca. 6100 BP. The timing of the wet shift at 5800 BP corresponds to wet periods in Western Europe. Peat accumulation rates were low (0.1 mm yr− 1) between ca. 5600 and ca. 3000 BP when sedges dominated the peatland. In the last 2500 yrs surface moisture fluctuated with wet events at ca. 2750–2400, and 2000 BP, and dry events at ca. 2250–2100 and 1450 BP. After 1450 BP a trend towards wetter conditions culminated at ca. 500 cal BP, possibly caused by local deforestation. Over the mire history, pH (inferred from testate amoebae) was mostly low (around 5) with two short-lived shifts to alkaline conditions (7.5) at ca. 6100 and 1450 BP indicating a minerotrophic influence from surface run-off into the mire. Up to about 1000 BP the ecological shifts inferred from the three proxies agree with palaeoclimatic records from Poland and Western Europe. After this date, however correlation is less clear suggesting an increasing local anthropogenic impact on the mire. This study confirms that kettle-hole peatlands can yield useful palaeoenvironmental data as well as recording land-use change and calls for more comparable studies in regions are the interface between major climate influences. 相似文献