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51.
Carolin Stangier Thomas Abel Julia Mierau Wildor Hollmann Heiko K. Strüder 《Journal of Sports Science and Medicine》2016,15(1):41-49
The purpose of this study was to compare the effects of running versus cycling training on sprint and endurance capacity in inline speed skating. Sixteen elite athletes (8 male, 8 female, 24 ± 8 yrs) were randomly assigned into 2 training groups performing either 2 session per week of treadmill running or ergometer cycling in addition to 3 skating specific sessions (technique, plyometrics, parkour) for 8 weeks. Training intensity was determined within non-specific (cycling or running) and effects on specific endurance capacity within a specific incremental exercise test. Before and after the intervention all athletes performed a specific (300m) and one non-specific (30s cycling or 200m running) all-out sprint test according to the group affiliation. To determine the accumulation of blood lactate (BLa) and glucose (BGL) 20 μl arterialized blood was drawn at rest, as well as in 1 min intervals for 10 min after the sprint test. The sport-specific peak oxygen uptake (VO2 peak) was significantly increased (+17%; p = 0.01) in both groups and highly correlated with the sprint performance (r = -0.71). BLa values decreased significantly (-18%, p = 0.02) after the specific sprint test from pre to post-testing without any group effect. However, BGL values only showed a significant decrease (-2%, p = 0.04) in the running group. The close relationship between aerobic capacity and sprint performance in inline speed skating highlights the positive effects of endurance training. Although both training programs were equally effective in improving endurance and sprint capacities, the metabolic results indicate a faster recovery after high intensity efforts for all athletes, as well as a higher reliance on the fat metabolism for athletes who trained in the running group.
Key points
- In addition to a highly developed aerobic performance inline speed skaters also require a highly trained anaerobic capacity to be effective in the sprint sections such as the mass start, tactical attacks and finish line sprint.
- An 8-week low-intensity endurance training program of either cycling or running training combined with additional routine training improves classical aerobic characteristics (17% increase of VO2 peak), as well as values for acceleration and speed.
- Athletes who trained in the running group demonstrated a higher reliance on the fat metabolism in the sport-specific post-testing.
- The significant reduction in anaerobic ATP turnover during repeated sprints appears to be partially compensated by an increase in VO2 in subsequent sprint. The results revealed a close relationship between the aerobic capacity and sprint performance in inline speed skating.
52.
Hao Wang Per Sikora Carolin Rutgersson Magnus Lindh Tomas Brodin Berndt Björlenius D.G. Joakim Larsson Heléne Norder 《International journal of hygiene and environmental health》2018,221(3):479-488
Sewage contains a mixed ecosystem of diverse sets of microorganisms, including human pathogenic viruses. Little is known about how conventional as well as advanced treatments of sewage, such as ozonation, reduce the environmental spread of viruses. Analyses for viruses were therefore conducted for three weeks in influent, after conventional treatment, after additional ozonation, and after passing an open dam system at a full-scale treatment plant in Knivsta, Sweden. Viruses were concentrated by adsorption to a positively charged filter, from which they were eluted and pelleted by ultracentrifugation, with a recovery of about 10%. Ion Torrent sequencing was used to analyze influent, leading to the identification of at least 327 viral species, most of which belonged to 25 families with some having unclear classification. Real-time PCR was used to test for 21 human-related viruses in inlet, conventionally treated, and ozone-treated sewage and outlet waters. The viruses identified in influent and further analyzed were adenovirus, norovirus, sapovirus, parechovirus, hepatitis E virus, astrovirus, pecovirus, picobirnavirus, parvovirus, and gokushovirus. Conventional treatment reduced viral concentrations by one to four log10, with the exception of adenovirus and parvovirus, for which the removal was less efficient. Ozone treatment led to a further reduction by one to two log10, but less for adenovirus. This study showed that the amount of all viruses was reduced by conventional sewage treatment. Further ozonation reduced the amounts of several viruses to undetectable levels, indicating that this is a promising technique for reducing the transmission of many pathogenic human viruses. 相似文献
53.
Carolin Hagelskamp David Schleifer Chloe Rinehart Rebecca Silliman 《Journal of urban health》2018,95(5):766-771
Participatory budgeting (PB)—a democratic process where ordinary residents decide directly how to spend part of a public budget—has gained impressive momentum in US municipalities, spreading from one pilot project in Chicago’s 49th ward in 2009 to 50 active PB processes across 14 cities in 2016–2017. Over 93,600 US residents voted in a PB process in 2015–2016, deciding over a total of about $49.5 million and funding 264 projects intended to improve their communities. The vast majority of US PB processes take place in large urban centers (e.g., New York City, Chicago, Seattle, Boston), but PB has also recently spread to some smaller cities and towns [1]. Figure 1 illustrates the growth of PB processes in the USA, and within New York City and Chicago council districts specifically.
PB constitutes a rare form of public engagement in that it typically comprises several distinct stages that encourage residents to participate from project idea collection to project implementation (see Fig. 2). The decisive public vote in US PB is practically binding as elected officials commit to implementing the public decision at the outset of the process. Moreover, all current PB processes in the USA have expanded voting rights to residents under 18 years old and to non-citizens. Under President Obama, the White House recognized PB as a model for open governance. Participatory Budgeting Project, a nonprofit organization that advocates for PB, won the 2014 Brown Democracy Medal, which recognizes the best work being done to advance democracy in the USA and internationally.
PB has been lauded for its potential to energize local democracy, contribute to more equitable public spending and help reduce inequality [2, 3]. Social justice goals have been explicit in US PB from the start. Grassroots advocates, technical assistance providers, and many elected officials who have adopted it emphasize that PB must focus on engaging underrepresented and marginalized communities [2, 4, 5]. PB steering committees have specified equity and inclusiveness goals in PB rule books [6, 7]. The most conclusive research so far on PB’s potential to reduce social inequalities, however, comes from Brazil, where PB started in 1989. In Brazil, PB has been associated with a reduction in extreme poverty, better access to public services, greater spending on sanitation and health services, and, most notably, a reduction in child and infant mortality [8, 9].In this paper, we outline three mechanisms by which PB could affect health disparities in US municipalities: First, by strengthening residents’ psychological empowerment; second, by strengthening civic sector alliances; and third, by (re)distributing resources to areas of greatest need. We summarize the theoretical argument for these impacts, discuss the existent empirical evidence, and highlight promising avenues for further research. 相似文献
54.
Rossmann H Büchler E Wenzel JJ Neukirch C du Prel JB Lackner KJ 《Clinical chemistry》2007,53(5):980-982
BACKGROUND: Allele frequencies of single-nucleotide polymorphisms (SNPs) can be quantified from DNA pools. The conventional preparation of DNA pools requires DNA isolation and quantification for each blood sample. We hypothesized that pooling of whole blood samples according to their leukocyte count, which determines DNA content, would be as reliable as the conventional pooling method but much less tedious to perform. METHODS: We collected 100 whole blood samples and measured the leukocyte count. Samples were frozen until further use. After thawing, pools were generated by combining aliquots containing an equal number of leukocytes. In parallel, DNA was extracted from another aliquot, DNA concentration was measured, and DNA concentration-based pools were assembled. All original samples were genotyped directly using 4 different SNP assays to obtain the exact allele frequencies in the pool. In addition, samples of known genotypes were mixed according to the DNA concentration or the leukocyte count to generate artificial samples of known allele frequencies. We analyzed pools and mixes in triplicate by pyrosequencing and calculated allelic frequencies. RESULTS: Leukocyte and DNA pooling provided equally accurate and precise SNP frequencies comparable to published data. CONCLUSION: DNA and leukocyte pooling are both suitable strategies to determine allele frequencies in frozen samples. The leukocyte pooling approach is much less tedious, quicker, and less expensive. It should be always considered if leukocyte counts are available. 相似文献
55.
Cathérine Ruther Carolin Gabler Hartmut Ewald Martin Ellenrieder Maximilian Haenle Tobias Lindner Wolfram Mittelmeier Rainer Bader Daniel Kluess 《Journal of orthopaedic research》2014,32(4):606-612
Implant osseointegration can currently only be assessed reliably post mortem. A novel method that relies on the principle of acoustic sound analysis was developed to enable examination of the longitudinal progress of osseointegration. The method is based on a magnetic sphere inside a hollow cylinder of the implant. By excitation using an external magnetic field, collision of the sphere inside the implant produces a sound signal. Custom‐made titanium implants equipped thusly were inserted in each lateral femoral epicondyle of 20 New Zealand White Rabbits. Two groups were investigated: Uncoated, machined surface versus antiadhesive surface; and calcium phosphate‐coated surface versus antiadhesive surface. The sound analysis was performed postoperatively and weekly. After 4 weeks, the animals were euthanized, and the axial pull‐out strengths of the implants were determined. A significant increase in the central frequency was observed for the loose implants (mean pull‐out strength 21.1 ± 16.9 N), up to 6.4 kHz over 4 weeks. In comparison, the central frequency of the osseointegrated implants (105.2 ± 25.3 N) dropped to its initial value. The presented method shows potential for monitoring the osseointegration of different implant surfaces and could considerably reduce the number of animals needed for experiments. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:606–612, 2014. 相似文献
56.
Guenter Karl Noé Sven Schiermeier Wolfgang Hatzmann Stefan Soltész Carolin Spüntrup Michael Anapolski 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2014,18(3)
Background and Objectives:
Laparoscopic surgery is associated with reduced morbidity, and postoperative pain is reduced. The aim of this study was to assess postoperative pain intensity, analgesic requirements, and the influence of cofactors after laparoscopic sacral colpopexy.Methods:
The study assessed 287 patients treated with laparoscopic sacropexy for genital prolapse with a Pelvic Organ Prolapse Quantification grade >1. Patients were asked to evaluate their pain postoperatively using a 4-point verbal pain rating scale. In addition, medical records were analyzed regarding the requirement for analgesic medication.Results:
Patients distinguished between abdominal pain and shoulder pain after laparoscopy. Abdominal pain reached maximum severity on day 1 and showed a good response to nonsteroidal antiphlogistics, whereas shoulder pain was rarely found (6.27%). Of the patients, 38% required no pain treatment or required 1 dose at most. The need for pain medication reached its climax on day 1 and decreased during the 5 following days. Non-opioid analgesics provided a sufficient therapeutic effect.Conclusion:
Laparoscopic sacropexy is associated with a moderate degree of postoperative pain. Non-opioid analgesics should be preferred as first-line therapy. The typical shoulder-tip pain showed only a low prevalence in our study group. From our point of view, the low rate of shoulder-tip pain corresponded with the low intra-abdominal carbon dioxide pressure. 相似文献57.
Gerald Meilicke MA Carolin von Gottberg Silvia Krumm Reinhold Kilian 《Pr?vention und Gesundheitsf?rderung》2014,9(2):123-129
Introduction
Employees are recommended to stay at home when they show symptoms of an acute respiratory infection. Yet, in case of an influenza pandemic another challenge is to promote the employees’ high willingness to report to work. For pandemic planning this raises the question, whether there is a conflict between these two goals.Method
Employee survey at the urban administration of Dortmund, Germany, about presenteeism with symptoms of an acute respiratory infection and the willingness to report to work during an influenza pandemic.Results
Results of multivariate linear regression indicated: There is only little association between propensity for presenteeism with symptoms of an acute respiratory infection and willingness to report to work during an influenza pandemic (R2?=?0,024).Conclusion
Results did not support the aforementioned conflict of goals between reducing presenteeism with symptoms of an acute respiratory infection and promoting willingness to report to work during an influenza pandemic. Further research should investigate interventions, which will support both goals alike, in order to support pandemic planning. 相似文献58.
Bastian Grewe Carolin Vogt Theresa Horstktter Bettina Tippler Han Xiao Bianca Müller Klaus Überla Ralf Wagner Benedikt Asbach Jens Bohne 《Viruses》2021,13(6)
Alternative splicing and the expression of intron-containing mRNAs is one hallmark of HIV gene expression. To facilitate the otherwise hampered nuclear export of non-fully processed mRNAs, HIV encodes the Rev protein, which recognizes its intronic response element and fuels the HIV RNAs into the CRM-1-dependent nuclear protein export pathway. Both alternative splicing and Rev-dependency are regulated by the primary HIV RNA sequence. Here, we show that these processes are extremely sensitive to sequence alterations in the 5’coding region of the HIV genomic RNA. Increasing the GC content by insertion of either GFP or silent mutations activates a cryptic splice donor site in gag, entirely deregulates the viral splicing pattern, and lowers infectivity. Interestingly, an adaptation of the inserted GFP sequence toward an HIV-like nucleotide bias reversed these phenotypes completely. Of note, the adaptation yielded completely different primary sequences although encoding the same amino acids. Thus, the phenotypes solely depend on the nucleotide composition of the two GFP versions. This is a strong indication of an HIV-specific mRNP code in the 5′ gag region wherein the primary RNA sequence bias creates motifs for RNA-binding proteins and controls the fate of the HIV-RNA in terms of viral gene expression and infectivity. 相似文献
59.
Beate Rieblinger Hicham Sid Denise Duda Tarik Bozoglu Romina Klinger Antonina Schlickenrieder Kamila Lengyel Krzysztof Flisikowski Tatiana Flisikowska Nina Simm Alessandro Grodziecki Carolin Perleberg Andrea Bhr Lucie Carrier Mayuko Kurome Valeri Zakhartchenko Barbara Kessler Eckhard Wolf Lutz Kettler Harald Luksch Ibrahim T. Hagag Daniel Wise Jim Kaufman Benedikt B. Kaufer Christian Kupatt Angelika Schnieke Benjamin Schusser 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(10)
Genetically modified animals continue to provide important insights into the molecular basis of health and disease. Research has focused mostly on genetically modified mice, although other species like pigs resemble the human physiology more closely. In addition, cross-species comparisons with phylogenetically distant species such as chickens provide powerful insights into fundamental biological and biomedical processes. One of the most versatile genetic methods applicable across species is CRISPR-Cas9. Here, we report the generation of transgenic chickens and pigs that constitutively express Cas9 in all organs. These animals are healthy and fertile. Functionality of Cas9 was confirmed in both species for a number of different target genes, for a variety of cell types and in vivo by targeted gene disruption in lymphocytes and the developing brain, and by precise excision of a 12.7-kb DNA fragment in the heart. The Cas9 transgenic animals will provide a powerful resource for in vivo genome editing for both agricultural and translational biomedical research, and will facilitate reverse genetics as well as cross-species comparisons.Chickens and pigs are the most important livestock species worldwide. They are not only important sources of food, but also valuable models for evolutionary biology and biomedical science. Pigs share a high anatomical and physiological similarity with humans and are an important species for translational biomedical research, for example, in the areas of cancer, diabetes, neurodegenerative, and cardiovascular diseases (1–3). They also resemble the human pathophenotype more closely than rodents. For example, pig models for familial adenomatous polyposis (FAP) develop polyps in the large intestine as observed in human patients (4), whereas mouse FAP models develop them in the small intestine (5). In contrast to mammals, chickens are phylogenetically distant vertebrates from humans, but they were instrumental in the field of developmental biology due to the easy access to the embryonated egg. They are used for studying neurological and cardiovascular functions (6–8) and provided key findings in B cell development and graft versus host responses (9–11). Genetically modified livestock species also hold great promise for agriculture by offering new approaches for disease control, such as genome-edited pigs resistant to Porcine Reproductive and Respiratory Syndrome or Avian Leucosis Virus (ALV)-resistant chickens (12–15).Due to the lack of fully functional embryonic stem cells, genetic engineering in pigs and chickens has been a laborious, inefficient, and time-consuming procedure (16). The generation of pigs with precise germline modifications required gene targeting in somatic cells followed by somatic cell nuclear transfer. This also is not practical in chickens, where precise alteration of the genome only became possible with recent improvements in the cultivation and manipulation of germline-competent primordial germ cells (PGCs) (17–19). These modified PGCs can be injected into the blood vessel system of stage 13 to 15 (Hamburger−Hamilton [HH]) embryos to produce germline chimeras and, by further breeding, genetically modified chickens.With the advent of synthetic endonucleases such as CRISPR-Cas9 efficiency of targeted germline modification has improved in both species (20–23). It still requires the generation and breeding of new founder lines, which is time consuming in large animals. To circumvent the need for generating germline-modified animals, attempts have been made to carry out genome editing directly in specific organs or tissues (24–27). But this has been hampered by the need to deliver both Cas9 and the required guide RNA (gRNA) and by the limited cargo capacity of viral vectors. To bypass this drawback, Cas9 transgenic mice have been generated, requiring delivery of only the respective gRNAs (28).Here, we describe the generation of both Cas9 transgenic pigs and chickens that ubiquitously express Cas9 endonuclease and provide proof of its function in vitro and in vivo. These animals provide an innovative and efficient model for in vivo genome editing to assess gene function in health and disease. 相似文献
60.
Marion J. Pollheimer Silvia Racedo Amanda Mikels-Vigdal Derek Marshall Christopher Bowlus Carolin Lackner Tobias Madl Tom H. Karlsen Johannes R. Hov Susan K. Lyman Joanne Adamkewicz Victoria Smith Emmanuel Moreau Gernot Zollner Tor Jacob Eide Tatjana Stojakovic Hubert Scharnagl Hans-Jürgen Gruber Peter Fickert 《Journal of hepatology》2018,68(2):368-377