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101.
Fluorescent silica nanoparticles (NPs–(SiO2–Fluo)) were synthesized based on the classical Störber method for cyanobacteria labelling. Modified mono-coloured SiO2 NPs with fluorescein (Fl) and rhodamine B (RhB) were obtained (NPs–(SiO2–Fl) and NPs–(SiO2–RhB)). Moreover, multi-coloured SiO2 NPs, via the incorporation of both emitters (NPs–(SiO2–RhB–Fl)), were tuned for optimal emissions and the biodetection of cyanobacteria. NPs–(SiO2–Fl) and NPs–(SiO2–RhB–Fl) were optimized for detection via laser fluorescence microscopy and in-flow cytometry with laser excitation and fluorescence detection. By TEM, homogeneous SiO2 NPs of 180.0 nm in diameter were recorded. These sizes were slightly increased due to the covalent linking incorporation of fluorescent dye emitters to 210.0 nm with mono-coloured fluorescent modified amine-organosilanes, and to 340.0 nm in diameter with multi-coloured dye incorporation. NPs–(SiO2–Fluo) showed variable emission depending on the dye emitter concentration, quantum yield and applied luminescent pathway. Thus, mono-coloured NPs–(SiO2–Fl) and NPs–(SiO2–RhB) showed diminished emissions in comparison to multi-coloured NPs–(SiO2–RhB–Fl). This enhancement was explained by fluorescence resonance energy transfer (FRET) between Fl as a fluorescent energy donor and RhB as an energy acceptor produced within the nanoarchitecture, produced only in the presence of both fluorophores with the appropriate laser excitation of the energy donor. The depositions of the nano-emitters on cyanobacteria by non-covalent interactions were observed by TEM and laser fluorescence microscopy. For multi-coloured NPs–(SiO2–RhB–Fl) labelling, bio-FRET was observed between the emission of the nano-labellers and the natural fluorophores from the cyanobacteria that quenched the emission of the whole nano-biostructure in comparison to mono-coloured NPs–(SiO2–Fl) labelling. This fact was explained and discussed in terms of different fluorescence energy transfer from the nanolabellers towards different natural chromophore coupling. In the presence of NPs–(SiO2–RhB–Fl) and NPs–(SiO2–RhB), the emission was coupled with lower quantum yield chromophores; while upon the application of NPs–(SiO2–Fl), it was coupled with higher quantum yield chromophores. In this manner, for enhanced luminescent nanoplatform tracking, the multi-coloured NPs–(SiO2–RhB–Fl) showed improved properties; but more highly luminescent bio-surfaces were generated with mono-coloured NPs–(SiO2–Fl) that permitted faster cyanobacteria detection and counting by laser fluorescence microscopy, and by in-flow cytometry with laser excitation and fluorescence detection.Fluorescent silica nanophotonics for cyanobacteria labelling. 相似文献
102.
Milos Kesek Abolghasem Saraj Carina Blomström-Lundqvist 《Scandinavian cardiovascular journal : SCJ》2013,47(2):130-133
An internal cardioverter defibrillator (ICD) is normally extensively tested during implantation. The necessity of retesting prior to discharge of the patient is a matter of debate. In our material of 30 patients undergoing first-time implantation of a transvenous internal defibrillator system, we retrospectively compare the predischarge defibrillation test with the peroperative test. A successful peroperative defibrillation test with no failed shocks at 10 J below maximal energy level was followed by a successful predischarge test with the same safety margin in 18/19 patients, while one patient required a maximal energy ICD shock for conversion at the predischarge test. We conclude that the predischarge defibrillation test can be omitted if the peroperative test was successful, with no failed shocks at 10 J below maximal energy level and if the shock therapy is set to maximal energy level. 相似文献
103.
Börje Svensson Ragnar Adell Carina Johansson Tomas Albrektsson Sten Holm 《Journal of plastic surgery and hand surgery》2013,47(3):247-259
Mandibular condyles are reconstructed immediately with costochondral grafts (CCGs) in children for several temporomandibular conditions, including ankylosis, benign neoplasia, and chronic arthritis. A prerequisite for growth of CCGs is that they are properly revascularised, but the revascularisation process has not to our knowledge so far been examined. The aim of the present study was therefore to investigate the revascularisation of CCGs when they were used for immediate reconstruction of the mandibular condyle in juvenile domestic pigs. Eleven mandibular condyles were experimentally resected and immediately reconstructed with CCGs. Microangiograms with an Indian ink solution were done 2, 4, 8, and 12 weeks after the reconstructions. The density of vessels was higher in measurement zones facing soft tissues than in those facing mandibular bone at all time points. Revascularisation of the growth plate originated from the surrounding recipient soft tissues and not from an endosteal blood supply from the host mandible ramus. 相似文献
104.
105.
Stroke induces extensive tissue remodeling, resulting in the activation of several cell types in the brain as well as recruitment of blood‐borne leucocytes. Radixin is part of a cytoskeleton linker protein family with the ability to connect transmembrane proteins to the actin cytoskeleton, promoting cell functions involving a dynamic cytoskeleton such as morphological changes, cell division and migration which are common events of different cell types after stroke. In the healthy adult brain radixin is expressed in Olig2+ cells throughout the brain and in neural progenitor cells in the subventricular zone. In the current study, we detected a 2.5 fold increase in the number of radixin positive cells in the peri‐infarct cortex two weeks after the induction of cortical stroke by photothrombosis. Similarly, the number of Olig2+ cells increased in the peri‐infarct area after stroke; however, the number of radixin+/Olig2+ cells was unchanged. Neural progenitor cells maintained radixin expression on their route to the infarct. More surprising however, was the expression of radixin in activated microglia in the peri‐infarct cortex. Seventy percent of Iba1+ cells expressed radixin after stroke, a population which was not present in the control brain. Furthermore, activation of radixin was predominantly detected in the peri‐infarct region of oligodendrocyte progenitors and microglia. The specific location of radixin+ cells in the peri‐infarct region and in microglia suggests a role for radixin in microglial activation after stroke. 相似文献
106.
Haas AN Silva-Boghossian CM Colombo AP Susin C Albandar JM Oppermann RV Rösing CK 《Journal of dentistry》2012,40(7):556-563
Objectives
To compare the subgingival microbiological outcomes of azithromycin or placebo as adjuncts to scaling and root planing (SRP) in the treatment of aggressive periodontitis (AgP), and to secondarily evaluate the microbiological effect of supragingival scaling in AgP patients.Methods
Twenty-four AgP subjects 13–26 years of age received a 15-day programme of supragingival scaling (SC) and were then randomly assigned to SRP with systemic azithromycin or placebo. Subgingival samples were taken with sterile paper points at baseline, 15 days after SC, and at 3, 6 and 12 months following SRP. Microbiological analysis was performed by the checkerboard DNA–DNA hybridization.Results
Changes in bacterial levels from baseline to 15 days after SC were similar in the 2 groups. When subjects were analysed as a single group, significant reductions after SC were observed for Actinomyces gerencseriae, Capnocytophaga ochracea, and Treponema denticola. During the 12-month follow-up, levels of most of the bacteria decreased in both groups in a similar pattern. For instance, Actinomyces israelli, Veillonella parvula, Streptococcus gordonii, C. ochracea, Eikenella corrodens, Eubacterium nodatum, Fusobacterium periodonticum and Fusobacterium nucleatum ssp. polymorphum decreased significantly within the groups.Conclusions
Azithromycin was ineffective in lowering the subgingival levels of important putative periodontal pathogens in young AgP subjects compared to placebo.Clinical significance
Scaling and root planing with adjunctive systemic azithromycin provides little additional benefit compared to placebo in reductions of major subgingival periodontal pathogens. 相似文献107.
Expression analysis of genes involved in collagen cross‐linking and its regulation in traumatic anterior shoulder instability
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Paulo Santoro Belangero Mariana Ferreira Leal Carina Cohen Eduardo Antônio Figueiredo Marília Cardoso Smith Carlos Vicente Andreoli Alberto de Castro Pochini Benno Ejnisman Moises Cohen 《Journal of orthopaedic research》2016,34(3):510-517
The molecular alterations involved in the capsule deformation presented in shoulder instability patients are poorly understood. Increased TGFβ1 acts as a signal for production of matrix macromolecules by fibrogenic cells at joint injury sites. TGFβ1, through its receptor TGFβR1, regulates genes involved in collagen cross‐linking, such as LOX, PLOD1, and PLOD2. We evaluated TGFβ1, TGFβR1, LOX, PLOD1, and PLOD2 gene expression in the antero‐inferior (macroscopically injured region), antero‐superior and posterior regions of the glenohumeral capsule of 29 shoulder instability patients and eight controls. We observed that PLOD2 expression was increased in the anterior‐inferior capsule region of the patients compared to controls. LOX expression tended to be increased in the posterior portion of patients. Patients with recurrent shoulder dislocation presented upregulation of TGFβR1 in the antero‐inferior capsule portion and of PLOD2 in the posterior region. Conversely, LOX was increased in the posterior portion of the capsule of patients with a single shoulder dislocation episode. In the antero‐inferior, LOX expression was inversely correlated and TGFβR1 was directly correlated with the duration of symptoms. In the posterior region, PLOD2, TGFβ1, and TGFβR1 were directly correlated with the duration of symptoms. In conclusion, PLOD2 expression was increased in the macroscopically injured region of the capsule of patients. Upregulation of TGFβ1, TGFβR1, and PLOD2 seems to be related with the maintenance of disease symptoms, especially in the posterior region. LOX upregulation seems to occur only in the initial phase of the affection. Therefore, TGFβ1, TGFβR1, LOX, and PLOD2 may play a role in shoulder instability. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:510–517, 2016. 相似文献
108.
Gabriela C. C. C. Maioral Carina Verna Manuel de J. Simões Helena B. Nader Ricardo S. Simões 《Gynecological endocrinology》2016,32(8):617-621
The aim of this study was to evaluate the amount of non- and sulfated glycosaminoglycans in the ovariectomized mice uterus, after treatment with ovarian steroids. For this purpose, 50 adult female mice were divided into five groups with 10 animals/each: control group: CG (ovary intact), and ovariectomized groups: OG (vehicle), EG (estradiol), PG (progesterone) and EPG (estradiol combined to progesterone). The treatments started 30 days after ovariectomy. All the animals were treated for 50 consecutive days. These hormones were administered in a sterile oily solution via gavage. Twenty-four hours after the last treatment, all animals were euthanized, removing the uterine horn for biochemical analyses. To quantify, the hyaluronic acid (HA) used ELISA-like fluorometric assay, and the sulfated glycosaminoglycans (GAGs) used agarose gel electrophoresis. The amount of HA was significantly higher in the group treated with progesterone (PG) compared to the others groups (p?0.05), and in the group treated with estradiol (EG), the amount of chondroitin/dermatan sulfate was significantly higher compared to the others groups (p?0.05), and in the group treated with progesterone (PG), the amount of heparan sulfate was significantly lower compared to the others groups, except to control group (p?0.05). Our results showed that the estroprogestative therapy after long time (50 days) profoundly affected the amount of glycosaminoglycans in uterine. These changes may be indicative of uterine pathology such as the development of tumor. 相似文献
109.
Anália S. Barhouch Alexandre V. Padoin Daniela S. Casagrande Raquel Chatkin Samanta P. Süssenbach Milene A. Pufal Carina Rossoni Cláudio C. Mottin 《Obesity surgery》2016,26(6):1178-1185
Background
The objective of this study was to analyze the factors associated with change in body mass index (BMI) and with percentage of excess weight loss (%EWL) in patients undergoing Roux-en-Y gastric bypass (RYGB). The following factors were analyzed: sex, age, surgical access (laparotomy vs. laparoscopy), preoperative BMI, waist circumference (WC), type 2 diabetes mellitus (T2DM), high blood pressure, and dyslipidemia.Methods
Retrospective cohort study using a convenience sample of 2070 patients of both sexes, aged 18 to 65 years, undergoing RYGB between 2000 and 2013. The outcomes of interest were BMI and %EWL at 0, 6, 12, 18, 24, 30, 36, 42, 48, 54, and 60 months after RYGB.Results
After 36, 48, and 60 months, approximately 50 % of patients had BMI >30 kg/m2. As for %EWL, 60-month results were poor for 17 % of patients (%EWL <50 %), good for 40 % of patients (%EWL 50–75 %), very good for 24 % of patients (%EWL from >75–90 %), and excellent for 19 % of patients (%EWL >90 %). The four most significant predictors of BMI change 60 months after RYGB (in descending order of magnitude) were preoperative BMI, preoperative WC, surgical access, and age; and of %EWL, surgical access, preoperative BMI, preoperative WC, and age.Conclusions
After 60 months of follow-up, the most relevant predictors of weight loss after RYGB were lower preoperative BMI and WC, videolaparoscopy as surgical access, and younger age. Further studies must be carried out to elucidate the impact of these factors on RYGB outcomes.110.
Prevalence and duration of breast milk feeding in very preterm infants: A 3‐year follow‐up study and a systematic literature review
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