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101.
Susan F Willis Desmond Barton Thomas EJ Ind 《International Seminars in Surgical Oncology : ISSO》2006,3(1):28
Background
The purpose of the study was to determine the outcome of all patients with endometrial adenocarcinoma cancer treated by laparoscopic hysterectomy at our institution, many of whom were high-risk for surgery.Methods
Data was collected by a retrospective search of the case notes and Electronic Patient Records of the thirty eight patients who underwent laparoscopic hysterectomy for endometrial cancer at our institutions.Results
The median body mass index was 30 (range 19–67). Comorbidities were present in 76% (29 patients); 40% (15 patients) had a single comorbid condition, whilst 18% (7 patients) had two, and a further 18% (7 patients) had more than two. Lymphadenectomy was performed in 45% (17 patients), and lymph node sampling in 21% (8 patients). Median operating time was 210 minutes (range 70–360 minutes). Median estimated blood loss was 200 ml (range 50–1000 ml). There were no intraoperative complications. Post-operative complications were seen in 21% (2 major, 6 minor). Blood transfusion was required in 5% (2 patients). The median stay was 4 post-operative nights (range 1–25 nights). In those patients undergoing lymphadenectomy, the mean number of nodes taken was fifteen (range 8–26 nodes). The pathological staging was FIGO stage I 76% (29 patients), stage II 8% (3 patients), stage III 16% (6 patients). The pathological grade was G1 31% (16 patients), G2 45% (17 patients), G3 24% (8 patients).Conclusion
Laparoscopic hysterectomy can be safely carried out in patients at high risk for surgery, with no compromise in terms of outcomes, whilst providing all the benefits inherent in minimal access surgery.102.
A sample of fixed bacterial cells was examined by immunofluorescence microscopy using an Alexa 488 conjugated secondary antibody for visualization. Excitation using visible light confirmed the expected photostability of this fluorophore; however, when using 2-photon excitation, Alexa 488 was rapidly and substantially photobleached. The unexpected instability of Alexa 488 under certain conditions may have deleterious consequences if not anticipated and accommodated in experimental protocols. 相似文献
103.
ABSTRACT. Millions of birds migrate across the Gulf of Mexico each year. However, most studies of migration in this region involve sampling onshore locations during the day, potentially underrepresenting the diversity and abundance of migrants passing the region. We evaluated a potential solution to this problem by recording the flight calls of passing migrants from an oil platform located southeast of the Alabama coast in the Gulf of Mexico. We detected 2762 calls during 30 nights from 9 September to 2 November 1999, and were able to identify 2329 calls to species. Flight calls by nine species of birds represented 23% of all identified calls. The greatest number of calls during one night (1017 calls) and during a 1-h period (257 calls) were recorded on 10 September. The greatest number of calls was recorded 8 h after sunset, with a secondary peak 2 h after sunset. The peak prior to sunrise may indicate the formation of flocks at dawn, and the peak after sunset may have been caused by the first wave of migrants reaching the platform. However, call counts varied extensively, with 98% of all calls recorded during 13 nights and 40% on a single night, possibly resulting from hourly and nightly differences in bird numbers aloft, atmospheric conditions, and artificial lighting conditions. Although recording on oil platforms can be difficult because of mechanical, wind, and wave noise, our results suggest great potential for describing the species composition of passing vocal migrants and the temporal patterns of flight-calling behavior if quiet recording locations can be found. Moreover, flight call monitoring could be a critically important tool for bird conservation in this region, given recent proposals to develop wind power and the potential bird mortality associated with such developments. 相似文献
104.
Yi‐Min She Keding Cheng Aaron Farnsworth Xuguang Li Terry D. Cyr 《Proteomics》2013,13(23-24):3537-3547
Inactivation of intact influenza viruses using formaldehyde or β‐propiolactone (BPL) is essential for vaccine production and safety. The extent of chemical modifications of such reagents on viral proteins needs to be extensively investigated to better control the reactions and quality of vaccines. We have evaluated the effect of BPL inactivation on two candidate re‐assortant vaccines (NIBRG‐121xp and NYMC‐X181A) derived from A/California/07/2009 pandemic influenza viruses using high‐resolution FT‐ICR MS‐based proteomic approaches. We report here an ultra performance LC MS/MS method for determining full‐length protein sequences of hemagglutinin and neuraminidase through protein delipidation, various enzymatic digestions, and subsequent mass spectrometric analyses of the proteolytic peptides. We also demonstrate the ability to reliably identify hundreds of unique sites modified by propiolactone on the surface of glycoprotein antigens. The location of these modifications correlated with changes to protein folding, conformation, and stability, but demonstrated no effect on protein disulfide linkages. In some cases, these modifications resulted in suppression of protein function, an effect that correlated with the degree of change of the modified amino acids’ side chain length and polarity. 相似文献
105.
Anwar M. Hashem Caroline Gravel Aaron Farnsworth Wei Zou Michelle Lemieux Kangwei Xu Changgui Li Junzhi Wang Marie-France Goneau Maria Merziotis Runtao He Michel Gilbert Xuguang Li 《PloS one》2013,8(2)
Vaccination is the most effective prophylactic method for preventing influenza. Quantification of influenza vaccine antigens is critically important before the vaccine is used for human immunization. Currently the vaccine antigen quantification relies on hemagglutinin content quantification, the key antigenic component, by single radial immunodiffusion (SRID) assay. Due to the inherent disadvantages associated with the traditional SRID; i.e. low sensitivity, low throughput and need for annual reagents, several approaches have been proposed and investigated as alternatives. Yet, most alternative methods cannot distinguish native hemagglutinin from denatured form, making them less relevant to antigenic analyses. Here, we developed a quantitative immunoassay based on the sialic acid binding property of influenza vaccine antigens. Specifically, we chemically synthesized human and avian influenza virus receptors analogues, N-acetylneuraminic acid-2,6-lactose and N-acetylneuraminic acid-2,3-lactose derivatives with an azidopropyl aglycon, using α-2,6- and α-2,3-sialyltransferases, respectively. The azido group of the two sialyllactose-derivatives was reduced and conjugated to mouse serum albumin through a squarate linkage. We showed that the synthetic α-2,6- and α-2,3-receptors selectively bound to human and avian-derived hemagglutinins, respectively, forming the basis of a new, and robust assay for hemagglutinin quantification. Hemagglutinin treated at high temperature or low pH was measured differentially to untreated samples suggesting native conformation is dependent for optimal binding. Importantly, this receptor-based immunoassay showed excellent specificity and reproducibility, high precision, less turnaround time and significantly higher sensitivity and throughput compared with SRID in analyzing multiple influenza vaccines. 相似文献
106.
We extend the concept that life is an informational phenomenon, at every level of organisation, from molecules to the global ecological system. According to this thesis: (a) living is information processing, in which memory is maintained by both molecular states and ecological states as well as the more obvious nucleic acid coding; (b) this information processing has one overall function—to perpetuate itself; and (c) the processing method is filtration (cognition) of, and synthesis of, information at lower levels to appear at higher levels in complex systems (emergence). We show how information patterns, are united by the creation of mutual context, generating persistent consequences, to result in ‘functional information’. This constructive process forms arbitrarily large complexes of information, the combined effects of which include the functions of life. Molecules and simple organisms have already been measured in terms of functional information content; we show how quantification may be extended to each level of organisation up to the ecological. In terms of a computer analogy, life is both the data and the program and its biochemical structure is the way the information is embodied. This idea supports the seamless integration of life at all scales with the physical universe. The innovation reported here is essentially to integrate these ideas, basing information on the ‘general definition’ of information, rather than simply the statistics of information, thereby explaining how functional information operates throughout life. 相似文献
107.
Habitat change in Rhodnius spp may represent an environmental challenge for the development of the species, particularly when feeding frequency and population density vary in nature. To estimate the effect of these variables in stability on development, the degree of directional asymmetry (DA) and fluctuating asymmetry (FA) in the wing size and shape of R. prolixus and R. robustus–like were measured under laboratory controlled conditions. DA and FA in wing size and shape were significant in both species, but their variation patterns showed both inter-specific and sexual dimorphic differences in FA of wing size and shape induced by nutrition stress. These results suggest different abilities of the genotypes and sexes of two sylvatic and domestic genotypes of Rhodnius to buffer these stress conditions. However, both species showed non-significant differences in the levels of FA between treatments that simulated sylvan vs domestic conditions, indicating that the developmental noise did not explain the variation in wing size and shape found in previous studies. Thus, this result confirm that the variation in wing size and shape in response to treatments constitute a plastic response of these genotypes to population density and feeding frequency. 相似文献
108.
Jaimie T. A. Dick Kevin Gallagher Suncica Avlijas Hazel C. Clarke Susan E. Lewis Sally Leung Dan Minchin Joe Caffrey Mhairi E. Alexander Cathy Maguire Chris Harrod Neil Reid Neal R. Haddaway Keith D. Farnsworth Marcin Penk Anthony Ricciardi 《Biological invasions》2013,15(4):837-846
Forecasting the ecological impacts of invasive species is a major challenge that has seen little progress, yet the development of robust predictive approaches is essential as new invasion threats continue to emerge. A common feature of ecologically damaging invaders is their ability to rapidly exploit and deplete resources. We thus hypothesized that the ‘functional response’ (the relationship between resource density and consumption rate) of such invasive species might be of consistently greater magnitude than those of taxonomically and/or trophically similar native species. Here, we derived functional responses of the predatory Ponto-Caspian freshwater ‘bloody red’ shrimp, Hemimysis anomala, a recent and ecologically damaging invader in Europe and N. America, in comparison to the local native analogues Mysis salemaai and Mysis diluviana in Ireland and Canada, respectively. This was conducted in a novel set of experiments involving multiple prey species in each geographic location and a prey species that occurs in both regions. The predatory functional responses of the invader were generally higher than those of the comparator native species and this difference was consistent across invaded regions. Moreover, those prey species characterized by the strongest and potentially de-stabilizing Type II functional responses in our laboratory experiments were the same prey species found to be most impacted by H. anomala in the field. The impact potential of H. anomala was further indicated when it exhibited similar or higher attack rates, consistently lower prey handling times and higher maximum feeding rates compared to those of the two Mysis species, formerly known as ‘Mysis relicta’, which itself has an extensive history of foodweb disruption in lakes to which it has been introduced. Comparative functional responses thus merit further exploration as a methodology for predicting severe community-level impacts of current and future invasive species and could be entered into risk assessment protocols. 相似文献
109.
Nicotinamide adenine dinucleotide (NAD+) is an essential electron transporter in mitochondrial respiration and oxidative phosphorylation. In genomic DNA, NAD+ also represents the sole substrate for the nuclear repair enzyme, poly(ADP-ribose) polymerase (PARP) and the sirtuin family of NAD-dependent histone deacetylases. Age associated increases in oxidative nuclear damage have been associated with PARP-mediated NAD+ depletion and loss of SIRT1 activity in rodents. In this study, we further investigated whether these same associations were present in aging human tissue. Human pelvic skin samples were obtained from consenting patients aged between 15–77 and newborn babies (0–1 year old) (n = 49) previously scheduled for an unrelated surgical procedure. DNA damage correlated strongly with age in both males (p = 0.029; r = 0.490) and females (p = 0.003; r = 0.600) whereas lipid oxidation (MDA) levels increased with age in males (p = 0.004; r = 0.623) but not females (p = 0.3734; r = 0.200). PARP activity significantly increased with age in males (p<0.0001; r = 0.768) and inversely correlated with tissue NAD+ levels (p = 0.0003; r = −0.639). These associations were less evident in females. A strong negative correlation was observed between NAD+ levels and age in both males (p = 0.001; r = −0.706) and females (p = 0.01; r = −0.537). SIRT1 activity also negatively correlated with age in males (p = 0.007; r = −0.612) but not in females. Strong positive correlations were also observed between lipid peroxidation and DNA damage (p<0.0001; r = 0.4962), and PARP activity and NAD+ levels (p = 0.0213; r = 0.5241) in post pubescent males. This study provides quantitative evidence in support of the hypothesis that hyperactivation of PARP due to an accumulation of oxidative damage to DNA during aging may be responsible for increased NAD+ catabolism in human tissue. The resulting NAD+ depletion may play a major role in the aging process, by limiting energy production, DNA repair and genomic signalling. 相似文献
110.
W E Farnsworth 《Membrane biochemistry》1990,9(2):141-162
The pivotal role of the cell nucleus in androgenic control of target organs, such as the prostate, has become increasingly suspect. Equally qualified receptor activities have been found in the cytosol, endoplasmic reticulum, and plasma membrane. It is presently difficult to explain how a sex steroid can manage proliferation, metabolism, biosynthesis and secretion, all through chromatin-directed signals. In my search for a more satisfactory mediator of androgen action, I discovered that the sodium-potassium-dependent ATPase of the prostate plasma membrane binds androgen, and is activated by the hormone's presence to serve as a metabolic pacemaker. This paper is my terminal status report on one aspect of this hypothesis; namely, the nature and site of androgen binding, with clues as to the mode of action. SDS-PAGE indicates that androgen can be bound to the beta-subunit of prostatic Na,K-ATPase. Selective enrichment of the enzyme by reversible coupling to either concanavalin A or a DHT-affinity column support this conclusion. Several studies show the dynamic effect of androgen binding: increased ouabain binding; enhancement of this binding by facilitated phosphorylation; spectroscopic evidence of conformational shifts, possibly consequences of these suggested activities for regulation, especially of metabolism, are examined. 相似文献