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81.
The objective of this study was to evaluate the efficacy of three eco-friendly control agents, either singly or in a pairwise combination, for the control of the tomato leafminer, Tuta absoluta (Meyrick) (Lep: Gelechiidae). They include the naturally derived pesticide spinosad, a commercially available formulation of Bacillus thuringiensis var. Kurstaki (Bt), and a native population of Trichogramma brassicae Bezdenko (Hym: Trichogrammatidae). Tomato plants containing the T. absoluta were treated with one of the seven following treatments in a greenhouse: (1) a single release of T. brassicae against the eggs; (2) two applications of Bt (2 kg ha?1); (3) and (4) one application of spinosad at two rates (60 and 120 g a.i. ha?1); (5) T. brassicae release?+?Bt spray; (6) T. brassicae release?+?spinosad spray; and (7) spinosad spray?+?Bt spray. The highest mortality rate was recorded for the spinosad?+?Bt (88.33?±?1.43%) and T. brassicae?+?spinosad (78.33?±?3.74%) combinations, respectively; while the lowest mortality rate was obtained through the single application of T. brassicae (31.67?±?4.84%). Based on our results, the Bt and spinosad seem to be suitable candidates for combination with other biological and cultural techniques towards an integrated management of the tomato leafminer. 相似文献
82.
Ruoqing Shen Ming-Chung Lin Farshid Sadeghi Jacob Rajfer Nstor F. Gonzalez-Cadavid Ronald S. Swerdloff 《The Journal of steroid biochemistry and molecular biology》1996,57(5-6):301-313
This study was undertaken to investigate the prevalent hypothesis that androgens are responsible for the organ-specific down-regulation of penile androgen receptors (ARs) and decline of penile growth in the rat during sexual maturation. Sexually immature male rats (21 days old) were castrated and treated for 3 days (“short-term”), with high doses of: (a) testosterone and the -reductase inhibitor finasteride (T/F); (b) dihydrotestosterone (DHT); or (c) finasteride alone (F). Intact and castrate controls received vehicle only. PolyA + RNA was analysed by Northern blot hybridization and ARs were estimated in the penis and ventral prostates by (3-H)R-1881 binding in the cytosol. Short-term castration, with or without F, increased penile AR mRNA, whereas high doses of T/F and DHT reduced it considerably. Although penile cytosol AR concentration in the control castrates, with or without F, paralleled the AR mRNA rise, treatment with androgens left cytosol AR content per organ and AR concentration above those of the intact rat penis despite the drop in AR mRNA. A “long-term” treatment (10 days) on 19-day-old rats with either medium or high doses of T/F and DHT also failed to down-regulate penile cytosol ARs below the intact controls. Western blot analysis of penile cytosol AR levels confirmed these results. Block of pituitary FSH and LH release by a GnRH antagonist in castrates receiving T/F or DHT at high doses did not modify the response. In the case of intact rats, high doses of T/F or DHT actually increased penile cytosol AR content. No difference was observed between T/F and DHT effects. In contrast to what occurs during sexual maturation, the prostate ARs and growth rate responded to all treatments in a similar way to what was observed in the penis. Our results suggest that increases in serum T or DHT are not major factors in the physiological down-regulation of ARs and androgen-dependent growth in the rat corpora cavernosa. 相似文献
83.
Shahram Ghanaati Adorján Kovács Mike Barbeck Jonas Lorenz Anna Teiler Nader Sadeghi Charles James Kirkpatrick Robert Sader 《Journal of cell communication and signaling》2016,10(1):3-15
Classically skin defects are covered by split thickness skin grafts or by means of local or regional skin flaps. In the presented case series for the first time a bilayered, non-crossed-linked collagen matrix has been used in an off-label fashion in order to reconstruct facial skin defects following different types of skin cancer resection. The material is of porcine origin and consists of a spongy and a compact layer. The ratio of the two layers is 1:3 in favour of the spongy layer. The aim of the study was to investigate the potential of this matrix for skin regeneration as an alternative to the standard techniques of skin grafts or flaps. Six patients between 39 and 83 years old were included in the study based on a therapeutic trial. The collagen matrix was used in seven defects involving the nose, eyelid, forehead- and posterior scalp regions, and ranging from 1,2 to 6 cm in diameter. Two different head and neck surgeons at two different institutions performed the operations. Each used a different technique in covering the wound following surgery, i.e. with and without a latex-based sheet under the pressure dressing. In three cases cylindrical biopsies were taken after 14 days. In all cases the biomaterial application was performed without any complication and no adverse effects were observed. Clinically, the collagen matrix contributed to a tension-free skin regeneration, independent of the wound dressing used. The newly regenerated skin showed strong similarity to the adjacent normal tissue both in quality and colour. Histological analysis indicated that the spongy layer replaced the defective connective tissue, by providing stepwise integration into the surrounding implantation bed, while the compact layer was infiltrated by mononuclear cells and contributed to its epithelialization by means of a ?conductive“process from the surrounding epithelial cells. The clinical and histological data demonstrate that the collagen bilayered matrix used in this series contributes to a ?Guided-Integrative-Regeneration-Process“, which still needs to be further understood. The biomimetic nature of this material seems to contribute to physiological matrix remodelling, which probably involves other matricellular proteins essential for soft tissue regeneration. A deeper understanding of the mechanism, involved in the tissue integration of this material and its contribution to soft tissue regeneration based on the direct and indirect effect of matricellular proteins could open new therapeutic avenues for biomaterial-based soft tissue regeneration as an alternative to traditional flap-based plastic surgery. 相似文献
84.
Immunological analyses of the chemotactic receptor of Dictyosteleum discoideum. Identification of cDNA clones 总被引:2,自引:0,他引:2
The cell surface cAMP receptor was excised from preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis and used to generate a polyclonal antiserum. The antiserum immunoprecipitates the two molecular weight forms of the cAMP receptor. Both forms are phosphorylated. Western blot analyses show that the antiserum is highly specific and recognizes only the two molecular weight forms of the cAMP receptor. Immunological studies indicate that both forms of the receptor are phosphorylated. Vegetative amoebae possess low levels of the cAMP receptor. Levels of the antigen increase in differentiated cells which express high cell surface cAMP binding activity. The antiserum was also used to isolate 6 lambda gt11 cDNA clones. One of those clones contains a 1.1-kilobase pair cDNA fragment which encodes for a protein of approximately 30,000-35,000 daltons. The antibody which binds to the fusion protein also recognizes the two molecular weight forms of the receptor. 相似文献
85.
Isolated cerebral capillaries from developing rats utilize glucose as well as ketone bodies essentially for oxidative metabolism. However, CO2 production from [U-14C]glucose was significantly greater than from ketone bodies (except at 5 mM). Ketone body utilization (in the presence of 5 mM glucose in the incubation medium) was concentration-dependent (up to 5 mM). Lipid synthesis from ketone bodies was comparable to that from glucose up to 1 mM. At concentrations 1 mM, acetoacetate incorporation into total lipids and fatty acids was higher than other substrates, however, this difference was statistically significant only at 5 mM. Incorporation of substrates into sterols was very low (> 1 pmol/h/mg protein). 相似文献
86.
H Sadeghi B S Wang A L Lumanglas J S Logan W R Baumbach 《Molecular endocrinology (Baltimore, Md.)》1990,4(12):1799-1805
GH specifically interacts with a soluble binding protein in serum. The GH-binding protein (GHBP) has been shown to contain the extracellular portion of the cell surface GH receptor (GHR). In rats and mice there is a unique mRNA that encodes the GHBP. This mRNA contains an alternatively spliced exon that replaces the transmembrane and intracellular domains of the receptor with a short hydrophilic carboxy-terminus of 17 and 25 amino acids, respectively, in rats and mice. In humans and other species no mRNAs encoding the GHBP have been identified, suggesting that the GHBP is in these cases a proteolytically processed GHR. In this study a monoclonal antibody (GHBP 4.3) was raised to the rat GHBP using as immunogen a synthetic peptide containing the unique C-terminal 17 amino acids that are not found in the rat GHR. As predicted, this antibody is specific to rat GHBP and does not cross-react with rat GHR. In combination with polyclonal and monoclonal antibodies that recognize both GHBP and GHR, this antibody was used to show that all, or most, of the GHBP in rat serum is indeed derived from the alternatively spliced GHBP mRNA and not from proteolytic processing of the GHR. In addition, endogenous rat serum GHBP was found to exist in two forms, with apparent mol wt of 52 and 44 kDa, arising from a single protein core of 32 kDa by extensive glycosylation. The concentrations of GHBP in male and female rat plasma were also estimated to be 300 and 575 ng/ml, respectively (measured in nonglycosylated GHBP equivalents). 相似文献
87.
Roman Pfeifer Philipp Lichte Helen Schreiber Richard M. Sellei Thomas Dienstknecht Cameron Sadeghi Hans-Christoph Pape Philipp Kobbe 《Cytokine》2013,61(2):585-590
IntroductionThe hemorrhagic shock (HS) model is commonly used to initiate a systemic post-traumatic inflammatory response. Numerous experimental protocols exist and it is unclear how differences in these models affect the immune response making it difficult to compare results between studies. The aim of this study was to compare the inflammatory response of different established protocols for volume-controlled shock in a murine model.MethodsMale C57/BL6 mice 6–10 weeks and weighing 20–25 g were subjected to volume-controlled or pressure-controlled hemorrhagic shock. In the volume-controlled group 300 μl, 500 μl, or 700 μl blood was collected over 15 min and mean arterial pressure was continuously monitored during the period of shock. In the pressure-controlled hemorrhagic shock group, blood volume was depleted with a goal mean arterial pressure of 35 mmHg for 90 min. Following hemorrhage, mice from all groups were resuscitated with the extracted blood and an equal volume of lactated ringer solution. Six hours from the initiation of hemorrhagic shock, serum IL-6, KC, MCP-1 and MPO activity within the lung and liver tissue were assessed.ResultsIn the volume-controlled group, the mice were able to compensate the initial blood loss within 30 min. Approximately 800 μl of blood volume was removed to achieve a MAP of 35 mmHg (p < 0.001). No difference in the pro-inflammatory cytokine (IL-6 and KC) profile was measured between the volume-controlled groups (300 μl, 500 μl, or 700 μl). The pressure-controlled group demonstrated significantly higher cytokine levels (IL-6 and KC) than all volume-controlled groups. Pulmonary MPO activity increased with the severity of the HS (p < 0.05). This relationship could not be observed in the liver.ConclusionVolume-controlled hemorrhagic shock performed following current literature recommendations may be insufficient to produce a profound post-traumatic inflammatory response. A decrease in the MAP following blood withdrawal (300 μl, 500 μl or 700 μl) was usually compensated within 30 min. Pressure-controlled hemorrhagic shock is a more reliable for induction of a systemic inflammatory response. 相似文献
88.
89.
Perspective: Evolution and detection of genetic robustness 总被引:23,自引:0,他引:23
de Visser JA Hermisson J Wagner GP Ancel Meyers L Bagheri-Chaichian H Blanchard JL Chao L Cheverud JM Elena SF Fontana W Gibson G Hansen TF Krakauer D Lewontin RC Ofria C Rice SH von Dassow G Wagner A Whitlock MC 《Evolution; international journal of organic evolution》2003,57(9):1959-1972
Abstract Robustness is the invariance of phenotypes in the face of perturbation. The robustness of phenotypes appears at various levels of biological organization, including gene expression, protein folding, metabolic flux, physiological homeostasis, development, and even organismal fitness. The mechanisms underlying robustness are diverse, ranging from thermodynamic stability at the RNA and protein level to behavior at the organismal level. Phenotypes can be robust either against heritable perturbations (e.g., mutations) or nonheritable perturbations (e.g., the weather). Here we primarily focus on the first kind of robustness–genetic robustness–and survey three growing avenues of research: (1) measuring genetic robustness in nature and in the laboratory; (2) understanding the evolution of genetic robustness; and (3) exploring the implications of genetic robustness for future evolution. 相似文献
90.
Omid Baziar Hamid Gholamhosseinian Seyed Amir Aledavood Mahboubeh Sadeghi 《Reports of Practical Oncology and Radiotherapy》2022,27(3):571
BackgroundTo investigate dose distribution of the 5cm spherical applicator of the INTRABEAM™ intraoperative radiation therapy (IORT) device via thermoluminescence dosimeters (TLDs) and Radiographic films. Independent dose distribution assessment of IORT devices is considered important. Several methods are described for this purpose, including TLDs and films. However, Radiographic films are not routinely used.Materials and methodsTwenty TLDs were used for depth dose measuring and evaluating the isotropy in water. Additionally, the isotropy was assessed separately via Radiographic films in air by drawing isodose curves.ResultsTLD measurements showed a steep dose decline which the relative average dose of 0.94 at the applicator surface reduced to 0.32, 0.13, and 0.07 at 1, 2, and 3 cm depths in water, respectively. Some remarkable isodose curves prepared using Radiographic films showed forward anisotropy of the 5 cm applicator.ConclusionA very steep dose decline and approximately isotropic dose distribution of the 5 cm applicator were observed via TLD measurements. Radiographic films showed acceptable potential for drawing dose distribution maps. However, they should be applied in more various radiation setups to be implemented more confidently. 相似文献