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71.
E Ricciardi M Jakimovska P Maniglio M Schimberni A Frega B Kobal M Moscarini 《World journal of surgical oncology》2012,10(1):177
ABSTRACT: BACKGROUND: Intraoperative injury of the obturator nerve has rarely been reported in patients with gynecological malignancies undergoing extensive radical surgeries. Irreversible damage of this nerve causes thigh paresthesia and claudication. Intraoperative repair may be done by end-to-end anastomosis or grafting when achieving tension-free anastomosis is not possible. CASE PRESENTATION: A 28-year-old woman with stage IB cervical cancer underwent fertility--sparing surgery, including conization and bilateral pelvic lymphadenectomy. The left obturator nerve was damaged intraoperatively during pelvic dissection. CONCLUSION: Immediate laparoscopic repair was successful and there was no functional deficit in the left thigh for six months postoperatively. 相似文献
72.
Plants infected with vertically transmitted fungal endophytes carry their microbial symbionts with them during dispersal into
new areas. Yet, whether seed-borne endophytes enhance the host plant’s ability to overcome colonisation barriers and to regenerate
within invaded sites remains poorly understood. We examined how symbiosis with asexual endophytic fungi (Neotyphodium) affected establishment and seed loss to predators in the invasive annual grass Lolium multiflorum (Italian ryegrass) across contrasting successional plots. Italian ryegrass seeds with high and low endophyte incidence were
sown into three communities: a 1-year-old fallow field, a 15-year-old grassland, and a 24-year-old forest, which conformed
to an old-field chronosequence in the eastern Inland Pampa, Argentina. We found that endophyte infection consistently increased
host population recruitment and reproductive output. Endophyte presence also enhanced aerial biomass production of ryegrass
in a low recruitment year but not in a high recruitment year, suggesting that symbiotic effects on growth performance are
density dependent. Endophyte presence reduced seed removal by rodents, although differential predation may not account for
the increased success of infected grass populations. Overall, there was no statistical evidence for an endophyte-by-site interaction,
indicating that the fungal endosymbiont benefitted host establishment regardless of large differences in biotic and abiotic
environment among communities. Our results imply that hereditary endophytes may increase the chances for host grass species
to pass various ecological filters associated with invasion resistance across a broad range of successional habitats. 相似文献
73.
Milov AD Samoilova MI Tsvetkov YD Jost M Peggion C Formaggio F Crisma M Toniolo C Handgraaf JW Raap J 《化学与生物多样性》2007,4(6):1275-1298
Three analogs of alamethicin F50/5, labelled with the TOAC (='2,2,6,6-tetramethylpiperidin-1-oxyl-4-amino-4-carboxylic acid') spin label at positions 1 (Alm1), 8 (Alm8), and 16 (Alm16), resp., were studied by Electron-Spin-Resonance (ESR) and Pulsed Electron-Electron Double-Resonance (PELDOR) techniques in solvents of different polarity to investigate the self-assembly of amphipathic helical peptides in membrane-mimicking environments. In polar solvents, alamethicin forms homogeneous solutions. In the weakly polar chloroform/toluene 1 : 1 mixture, however, this peptide forms aggregates that are detectable at 293 K by ESR in liquid solution, as well as by PELDOR in frozen, glassy solution at 77 K. In liquid solution, free alamethicin molecules and their aggregates show rotational-mobility correlation times tau(r) of 0.87 and 5.9 ns, resp. Based on these values and analysis of dipole-dipole interactions of the TOAC labels in the aggregates, as determined by PELDOR, the average number N of alamethicin molecules in the aggregates is estimated to be less than nine. A distance-distribution function between spin labels in the supramolecular aggregate was obtained. This function exhibits two maxima: a broad one at a distance of 3.0 nm, and a wide one at a distance of ca. 7 nm. A molecular-dynamics (MD)-based model of the aggregate, consisting of two parallel tetramers, each composed of four molecules arranged in a 'head-to-tail' fashion, is proposed, accounting for the observed distances and their distribution. 相似文献
74.
The activity and localization of fructose-1,6-bisphosphatase (FBPase; EC 3.1.3.11) in blood leukocytes of patients with type 1 diabetes mellitus and healthy adults were investigated immunocytochemically. The amount of polymorphonuclear (PMN) and mononuclear (MN) cells with positive FBPase immunocytochemical reaction was 57% and 68%, respectively, in pathological, and 38% and 42%, respectively, in healthy donors. Results of light microscopic investigations were confirmed by measurements of FBPase activity following lysis of PMN and MN cells. The enzyme activity of PMN and MN leukocytes was higher in diabetes mellitus than in healthy adults, by 30% and 127%, respectively. Using immunocytochemistry together with electron microscopy, FBPase was detected not only in the cytoplasm but also in the nucleus of leukocytes of both patients with insulin-dependent diabetes mellitus and healthy donors. 相似文献
75.
Marina Burgos-Silva Patricia Semedo-Kuriki Cassiano Donizetti-Oliveira Priscilla Barbosa Costa Marco Antonio Cenedeze Meire Ioshie Hiyane Alvaro Pacheco-Silva Niels Olsen Saraiva Camara 《PloS one》2015,10(11)
Acute and chronic kidney injuries (AKI and CKI) constitute syndromes responsible for a large part of renal failures, and are today still associated with high mortality rates. Given the lack of more effective therapies, there has been intense focus on the use stem cells for organ protective and regenerative effects. Mesenchymal stem cells (MSCs) have shown great potential in the treatment of various diseases of immune character, although there is still debate on its mechanism of action. Thus, for a greater understanding of the role of MSCs, we evaluated the effect of adipose tissue-derived stem cells (AdSCs) in an experimental model of nephrotoxicity induced by folic acid (FA) in FVB mice. AdSC-treated animals displayed kidney functional improvement 24h after therapy, represented by reduced serum urea after FA. These data correlated with cell cycle regulation and immune response modulation via reduced chemokine expression and reduced neutrophil infiltrate. Long-term analyses, 4 weeks after FA, indicated that AdSC treatment reduced kidney fibrosis and chronic inflammation. These were demonstrated by reduced interstitial collagen deposition and tissue chemokine and cytokine expression. Thus, we concluded that AdSC treatment played a protective role in the framework of nephrotoxic injury via modulation of inflammation and cell cycle regulation, resulting in reduced kidney damage and functional improvement, inhibiting organ fibrosis and providing long-term immune regulation. 相似文献
76.
A novel family of sequence-specific endoribonucleases associated with the clustered regularly interspaced short palindromic repeats 总被引:3,自引:0,他引:3
Beloglazova N Brown G Zimmerman MD Proudfoot M Makarova KS Kudritska M Kochinyan S Wang S Chruszcz M Minor W Koonin EV Edwards AM Savchenko A Yakunin AF 《The Journal of biological chemistry》2008,283(29):20361-20371
Clustered regularly interspaced short palindromic repeats (CRISPRs) together with the associated CAS proteins protect microbial cells from invasion by foreign genetic elements using presently unknown molecular mechanisms. All CRISPR systems contain proteins of the CAS2 family, suggesting that these uncharacterized proteins play a central role in this process. Here we show that the CAS2 proteins represent a novel family of endoribonucleases. Six purified CAS2 proteins from diverse organisms cleaved single-stranded RNAs preferentially within U-rich regions. A representative CAS2 enzyme, SSO1404 from Sulfolobus solfataricus, cleaved the phosphodiester linkage on the 3'-side and generated 5'-phosphate- and 3'-hydroxyl-terminated oligonucleotides. The crystal structure of SSO1404 was solved at 1.6A resolution revealing the first ribonuclease with a ferredoxin-like fold. Mutagenesis of SSO1404 identified six residues (Tyr-9, Asp-10, Arg-17, Arg-19, Arg-31, and Phe-37) that are important for enzymatic activity and suggested that Asp-10 might be the principal catalytic residue. Thus, CAS2 proteins are sequence-specific endoribonucleases, and we propose that their role in the CRISPR-mediated anti-phage defense might involve degradation of phage or cellular mRNAs. 相似文献
77.
78.
Andrea Gloria‐Soria Diego Ayala Ambicadutt Bheecarry Olger Calderon‐Arguedas Dave D. Chadee Marina Chiappero Maureen Coetzee Khouaildi Bin Elahee Ildefonso Fernandez‐Salas Hany A. Kamal Basile Kamgang Emad I. M. Khater Laura D. Kramer Vicki Kramer Alma Lopez‐Solis Joel Lutomiah Ademir Martins Jr Maria Victoria Micieli Christophe Paupy Alongkot Ponlawat Nil Rahola Syed Basit Rasheed Joshua B. Richardson Amag A. Saleh Rosa Maria Sanchez‐Casas Gonçalo Seixas Carla A. Sousa Walter J. Tabachnick Adriana Troyo Jeffrey R. Powell 《Molecular ecology》2016,25(21):5377-5395
Mosquitoes, especially Aedes aegypti, are becoming important models for studying invasion biology. We characterized genetic variation at 12 microsatellite loci in 79 populations of Ae. aegypti from 30 countries in six continents, and used them to infer historical and modern patterns of invasion. Our results support the two subspecies Ae. aegypti formosus and Ae. aegypti aegypti as genetically distinct units. Ae. aegypti aegypti populations outside Africa are derived from ancestral African populations and are monophyletic. The two subspecies co‐occur in both East Africa (Kenya) and West Africa (Senegal). In rural/forest settings (Rabai District of Kenya), the two subspecies remain genetically distinct, whereas in urban settings, they introgress freely. Populations outside Africa are highly genetically structured likely due to a combination of recent founder effects, discrete discontinuous habitats and low migration rates. Ancestral populations in sub‐Saharan Africa are less genetically structured, as are the populations in Asia. Introduction of Ae. aegypti to the New World coinciding with trans‐Atlantic shipping in the 16th to 18th centuries was followed by its introduction to Asia in the late 19th century from the New World or from now extinct populations in the Mediterranean Basin. Aedes mascarensis is a genetically distinct sister species to Ae. aegypti s.l. This study provides a reference database of genetic diversity that can be used to determine the likely origin of new introductions that occur regularly for this invasive species. The genetic uniqueness of many populations and regions has important implications for attempts to control Ae. aegypti, especially for the methods using genetic modification of populations. 相似文献
79.
Despite their low prevalence, genetic kidney diseases (GKD) still represent a serious health problem. They often lead to kidney failure and to the consequent need of dialysis or kidney transplant. To date, reliable diagnosis requires laborious genetic tests and/or a renal biopsy. Moreover, only scant and non-specific markers exist for prognostic purposes. Biomarkers assayed in an easily available and low-cost sample, such as urine, would be highly valuable. Urinary proteomics can provide clues related to their development through the identification of differentially expressed proteins codified by the affected genes, or other dis-regulated species, in total or fractionated urine, providing novel mechanistic insights. In this review, the authors summarize and discuss the results of the main proteomic investigations on GKD urine samples and in urinary extracellular vesicles. 相似文献
80.
Guizzetti M Moore NH Giordano G Costa LG 《The Journal of biological chemistry》2008,283(46):31884-31897
Astrocytes have been shown to release factors that have promoting or inhibiting effects on neuronal development. However, mechanisms controlling the release of such factors from astrocytes are not well established. Astrocytes express muscarinic receptors whose activation stimulates a robust intracellular signaling, although the role of these receptors in glial cells is not well understood. Acetylcholine and acetylcholine receptors are present in the brain before synaptogenesis occurs and are believed to be involved in neuronal maturation. The present study was undertaken to investigate whether stimulation of muscarinic receptors in astrocytes would modulate neurite outgrowth in hippocampal neurons. Rat hippocampal neurons, co-cultured with rat cortical astrocytes previously exposed to the cholinergic agonist carbachol, displayed longer neurites. The effect of carbachol in astrocytes was due to the activation of M3 muscarinic receptors. Exposure of astrocytes to carbachol increased the expression of the extracellular matrix proteins fibronectin and laminin-1 in these cells. This effect was mediated in part by an increase in laminin-1 and fibronectin mRNA levels and in part by the up-regulation of the production and release of plasminogen activator inhibitor-1, an inhibitor of the proteolytic degradation of the extracellular matrix. The inhibition of fibronectin activity strongly reduced the effect of carbachol on the elongation of all the neurites, whereas inhibition of laminin-1 activity reduced the elongation of minor neurites only. Plasminogen activator inhibitor-1 also induced neurite elongation through a direct effect on neurons. Taken together, these results demonstrate that cholinergic muscarinic stimulation of astrocytes induces the release of permissive factors that accelerate neuronal development. 相似文献