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941.
942.
Hadjkacem L Hadj-Kacem H Boulila A Bahloul A Ayadi H Ammar-Keskes L 《Annales de génétique》2004,47(3):217-224
Several reports implicated a relation between the trinucleotide (CAG) repeat length in the androgen receptor (AR) gene and male infertility. But such result was not reproduced in others. To test this hypothesis, we investigated the number of (CAG) repeats in the AR gene among two groups of infertile (n = 129) and fertile Tunisian men (n = 98), using polymerase chain reaction (PCR) targeting the AR CAG repeat tract, followed by electrophoresis on polyacrylamide gel (6%). For statistical analysis we used Student, Kolmogorov-Smirnov (KS) and chi(2)-tests. Significance was reached when P < 0.05. No statistically significant difference in the mean length of the CAG repeat was found between infertile and control groups (P = 0.47). Moreover, using KS test, we have not found a difference in the distribution of allele frequencies between infertile and controls (D(obs) = 0.046 < D(crit) = 0.180). We also did not found a statistically significant relationship between the size of the CAG repeat and impaired sperm production in Tunisian population. Our results may be attributed to the high probability that infertile males may represent a heterogeneous group with respect to the causes of defective spermatogenesis. 相似文献
943.
Using aerated compost tea in comparison with a chemical pesticide for controlling rose powdery mildew 总被引:1,自引:0,他引:1
Samin Seddigh Leila Kiani Bahram Tafaghodinia Bahareh Hashemi 《Archives Of Phytopathology And Plant Protection》2013,46(6):658-664
Rose powdery mildew (Sphaerotheca pannosa var. rosae) is one of the most common foliar diseases of roses worldwide. Application of chemical products on the plant or in the soil kills a range of the beneficial micro-organisms thereby disturbing ecosystem. Compost tea helps to restore and increase the populations of those beneficial micro-organisms. The objective of the present study was to evaluate the comparison of biopesticide (compost tea) and a chemical pesticide. The experiment was performed in three treatments, which were compost tea, fungicide (Topaz) and no treatment in three replications. After foliar applications of biopesticide and fungicide, the control percentage was estimated based on the number of infected flowers with powdery mildew. The results indicated that there was a significant difference between these treatments on rose in controlling powdery mildew (F?=?23.25, p?=?0.0015, df?=?2), at a probability level of 1% (p???0.01). So, that control percentage of compost tea treatment was the most. 相似文献
944.
945.
Blossom-end rot is generally considered a calcium-related physiological disorder. The results of the previous studies show that several factors such as plant conditions can be effective on the blossom-end rot incidence. Therefore, the present study was undertaken to investigate the effect of the sink/source ratio on the incidence of the blossom-end rot of two greenhouse tomato (Solanum lycopersicum L.) cultivars: ‘Grandella’ and ‘Isabella’. To this end, four treatments were applied: saving one fruit per truss (1F), two fruits per truss (2F), three fruits per truss (3F), and no fruit pruning (control). The results showed that the tomato cultivar ‘Isabella’ was more susceptible to the blossom-end rot than ‘Grandella’. Decreasing the sink/source ratio increased the incidence of the blossom-end rot and the relative fruit growth rate. The correlation between the blossom-end rot incidence and the relative fruit growth rate showed that the fruit growth rate could be regarded as an important factor in the incidence of this disorder. Endogenous auxin and cytokinin concentrations acted as the regulators of the fruit growth rate and influenced it. Slowing down the relative growth rate by keeping proper sink/source ratio based on tomato cultivar is, therefore, an effective, cheap and healthy way to control the incidence of the blossom-end rot, especially in organic farming. 相似文献
946.
Paul A. Garber Elizabeth K. Mallott Leila M. Porter Andres Gomez 《American journal of primatology》2019,81(10-11)
Body mass is a strong predictor of diet and nutritional requirements across a wide range of mammalian taxa. In the case of small‐bodied primates, because of their limited gut volume, rapid food passage rate, and high metabolic rate, they are hypothesized to maintain high digestive efficiency by exploiting foods rich in protein, fats, and readily available energy. However, our understanding of the dietary requirements of wild primates is limited because little is known concerning the contributions of their gut microbiome to the breakdown and assimilation of macronutrients and energy. To study how the gut microbiome contributes to the feeding ecology of a small‐bodied primate, we analyzed the fecal microbiome composition and metabolome of 22 wild saddleback tamarins (adult body mass 360–390 g) in Northern Bolivia. Samples were analyzed using high‐throughput Illumina sequencing of the 16 S rRNA gene V3‐V5 regions, coupled with GC‐MS metabolomic profiling. Our analysis revealed that the distal microbiome of Leontocebus weddelli is largely dominated by two main bacterial genera: Xylanibacter and Hallella (34.7 ± 14.7 and 22.6 ± 12.4%, respectively). A predictive analysis of functions likely carried out by bacteria in the tamarin gut demonstrated the dominance of membrane transport systems and carbohydrate metabolism as the predominant metabolic pathways. Moreover, given a fecal metabolome composed mainly of glucose, fructose, and lactic acid (21.7 ± 15.9%, 16.5 ± 10.7%, and 6.8 ± 5.5%, respectively), the processing of highly fermentable carbohydrates appears to play a central role in the nutritional ecology of these small‐bodied primates. Finally, the results also show a potential influence of environmentally‐derived bacteria in colonizing the tamarin gut. These results indicate high energetic turnover in the distal gut of Weddell's saddleback tamarin, likely influenced by dominant bacterial taxa that facilitate dietary dependence on highly digestible carbohydrates present in nectar, plant exudates, and ripe fruits. 相似文献
947.
Patrícia M. Ferrão Líndice M. Nisimura Otacílio C. Moreira Marcelo G. Land Mirian C. Pereira Leila de Mendonça-Lima Tania C. Araujo-Jorge Mariana C. Waghabi Luciana R. Garzoni 《Experimental cell research》2018,362(2):260-267
Chagasic cardiomyopathy (CC) is the main manifestation of Chagas Disease (CD). CC is a progressive dysfunctional illness, in which transforming growth factor beta (TGF-β) plays a central role in fibrogenesis and hypertrophy. In the present study, we tested in a three-dimensional (3D) model of cardiac cells culture (named cardiac spheroids), capable of mimicking the aspects of fibrosis and hypertrophy observed in CC, the role of TGF-β pathway inhibition in restoring extracellular matrix (ECM) balance disrupted by T. cruzi infection. Treatment of T. cruzi-infected cardiac spheroids with SB 431542, a selective inhibitor of TGF-β type I receptor, resulted in a reduction in the size of spheroids, which was accompanied by a decrease in parasite load and in fibronectin expression. The inhibition of TGF-β pathway also promoted an increase in the activity of matrix metalloproteinase (MMP)-2 and a decrease in tissue inhibitor of matrix metalloproteinase (TIMP)-1 expression, which may be one of the mechanisms regulating extracellular matrix remodeling. Therefore, our study provides new insights into the molecular mechanisms by which inhibition of TGF-β signaling reverts fibrosis and hypertrophy generated by T. cruzi during CC and also highlights the use of cardiac spheroids as a valuable tool for the study of fibrogenesis and anti-fibrotic compounds. 相似文献
948.
Leila Gannoun-Zaki Isabelle Pieri Josette Badet Denis Barritault 《Journal of cellular biochemistry》1996,62(2):240-250
The internalization of basic fibroblast growth factor (FGF-2) was studied in Chinese hamster lung fibroblasts (CCL39). Recombinant FGF-2 was derivatized with a photoactivable agent, N-hydroxysuccinimidyl-4-azido-benzoate (HSAB), iodinated, and used to visualize intracellular FGF-2-affinity-labeled molecules after internalization at 37°C. Iodinated HSAB-FGF-2 maintained the properties of natural FGF-2 such as affinity for heparin, binding to Bek and Flg receptors, interaction with high- and low-affinity binding sites, and reinitiating of DNA synthesis in CCL39 cells. Affinity-labeling experiments at 4°C with 125I-HSAB-FGF-2 led to the detection of several FGF-cell surface complexes with apparent molecular mass of 80, 100, 125, 150, 170–180, 220, 260, and about 320 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), whereas two specific bands at 80 and 130–160 kDa were obtained using the homobifunctional cross-linking reagent, disuccinimidyl suberate. When the cells, preincubated with 125I-HSAB-FGF-2 at 4°C and then washed, were shifted to 37°C, irradiation of the internalized labeled FGF-2 led to detection of a similar but fainted profile with one major specific band at 80 kDa. Heparitinase II treatment of the cells reduced binding of 125I-HSAB-FGF-2 to its cell surface sites by 80% and internalization by 55%, indicating the involvement of heparan sulfate proteoglycans in these processes. Among the heparitinase-sensitive bands was the 80-kDa complex. © 1996 Wiley-Liss, Inc. 相似文献
949.
Sonia Ndeupen Aurlie Bouteau Christopher Herbst Zhen Qin Sonya Jacobsen Nicholas E. Powers Zachary Hutchins Drishya Kurup Leila Zabihi Diba Megan Watson Holly Ramage Botond Z. Igyrt 《PLoS pathogens》2022,18(1)
Nucleoside modified mRNA combined with Acuitas Therapeutics’ lipid nanoparticles (LNPs) has been shown to support robust humoral immune responses in many preclinical animal vaccine studies and later in humans with the SARS-CoV-2 vaccination. We recently showed that this platform is highly inflammatory due to the LNPs’ ionizable lipid component. The inflammatory property is key to support the development of potent humoral immune responses. However, the mechanism by which this platform drives T follicular helper (Tfh) cells and humoral immune responses remains unknown. Here we show that lack of Langerhans cells or cDC1s neither significantly affected the induction of PR8 HA and SARS-CoV-2 RBD-specific Tfh cells and humoral immune responses, nor susceptibility towards the lethal challenge of influenza and SARS-CoV-2. However, the combined deletion of these two DC subsets led to a significant decrease in the induction of PR8 HA and SARS-CoV-2 RBD-specific Tfh cell and humoral immune responses. Despite these observed defects, these mice remained protected from lethal influenza and SARS-CoV-2 challenges. We further found that IL-6, unlike neutrophils, was required to generate normal Tfh cells and antibody responses, but not for protection from influenza challenge.In summary, here we bring evidence that the mRNA-LNP platform can support the induction of protective immune responses in the absence of certain innate immune cells and cytokines. 相似文献
950.
Pancreatic Endoderm‐Derived From Diabetic Patient‐Specific Induced Pluripotent Stem Cell Generates Glucose‐Responsive Insulin‐Secreting Cells 下载免费PDF全文