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1.
Biol Bull ; 242(3): 222-237, 2022 06.
Article in English | MEDLINE | ID: mdl-35767415

ABSTRACT

AbstractThe calyptraeids Crepidula adunca and Crepidula norrisiarum, both direct developers, are abundant in the shallow waters of the northeastern Pacific. They have long been considered as two allopatric species that live on different hosts and differ in body size. In this study, we rigorously test this historical hypothesis by assessing molecular taxonomy, museum records, new morphological and host observations, and population genetic structure along the northeast Pacific coast. Results show that, contrary to previous understanding, the distributions of the two species largely overlap and that size does not effectively distinguish them, especially in the northern part of the range where the nominal "C. adunca" has been studied. Newly recognized northern occurrences of C. norrisiarum demonstrate that both species have similar, disrupted distributions that range from British Colombia through southern California. Neither species is reported to occur on the outer shores of southern Washington or Oregon, the exception being records of C. adunca at Cape Arago, Oregon. Despite this apparent geographic gap, neither species shows appreciable genetic differentiation between the northern and southern parts of its ranges. Despite body size having been used to distinguish these species, our observations do not support body size as a species-specific trait; rather, they support a new hypothesis that body size variation reflects regional differences in host use and host availability.


Subject(s)
Gastropoda , Animals , Phylogeny , Species Specificity
2.
Surgeon ; 19(6): 321-328, 2021 Dec.
Article in English | MEDLINE | ID: mdl-33439832

ABSTRACT

PURPOSE: Creation of an optimal bowel anastomosis with low postoperative leakage rate is an immanent part of colorectal surgery contributing to recovery, length of hospital stay and overall hospital costs. We aimed to investigate costs of small and large bowel resection, length of hospital stay, anastomotic leakage rate and its risk factors depending on the anastomotic technique. METHODS: Retrospective analysis of 198 patients (67 stapled and 131 hand-sewn anastomoses) undergoing elective bowel resection with a single anastomosis without protective ileostomy either stapled or in double-rowed running suture technique between 1st October 2012 and 30th September 2018 at Charité University Hospital Berlin, Campus Benjamin Franklin. We analyzed costs of treatment, total length of hospital stay, rate of anastomotic leakage and possible risk factors for anastomotic leak. RESULTS: No significant difference between both anastomotic techniques could be detected for hospital stay (p = 0.754), 30-day-readmission rate (p = 0.827), or anastomotic leakage (p = 606). Neither comorbidities (p = 0.449), underlying disease (p = 0.132), experience of the surgical team (p = 0.828) nor scheduling of the operation (p = 0.531) were associated with anastomotic leakage. Stapled anastomoses took 22 min less operation time than sutured anastomoses (130 vs. 152 min. Median) (p = 0.001). Operations with stapled anastomoses saved 183 € in operation costs and 496 € in overall hospital costs. CONCLUSION: Stapled and hand-sewn bowel anastomoses can be performed equally safe without differences in postoperative outcome. No patient, procedure or surgeon related risk factors for anastomotic leakage could be detected. Bowel resections with stapled anastomoses take less time and save operation and overall hospital costs.


Subject(s)
Diagnosis-Related Groups , Surgical Stapling , Anastomosis, Surgical , Cost-Benefit Analysis , Humans , Retrospective Studies
3.
Int J Colorectal Dis ; 32(8): 1125-1135, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28315018

ABSTRACT

BACKGROUND: Low anterior resection (LAR) for rectal cancer is a potentially challenging operation due to limited space in the pelvis. CT pelvimetry allows to quantify pelvic space, so that its relationship with outcome after LAR may be assessed. Studies investigating this, however, yielded conflicting results. We hypothesized that a small pelvis is associated with a higher rate of incomplete mesorectal excision, anastomotic leakages, and increased rate of urinary dysfunction in patients operated for rectal cancer. METHODS: In a single-center retrospective analysis, we studied 74 patients that underwent LAR for rectal cancer with primary anastomosis. Thin-layered multi-slice CT datasets were used for slice by slice depiction of the inner pelvic surface, and the inner pelvic volume was automatically compounded. The primary outcome was quality of total mesorectal excision (TME; Mercury grading); secondary outcomes were anastomotic leakage and urinary dysfunction with regard to pelvic dimensions. Univariate analyses and multiple logistic regression analyses were performed for the primary and the secondary outcomes. RESULTS: Shorter obstetric conjugate diameters were associated with a higher probability of a worse TME quality (110.8 ± 10.2 vs. 105.0 ± 8.6 mm; OR 0.85; 95% CI 0.73-0.99; p = 0.038). Short interspinous distance showed a trend towards an increased risk for deteriorated TME quality (OR 0.88; 95% CI 0.76-1.0; p = 0.06). Anastomotic leakage was associated with anemia (OR 2.77; 95% CI 1.0-7.7; p = 0.047). Association between pelvic diameters or pelvic volume and anastomotic leakage or urinary dysfunction was not observed. Perioperative blood transfusions were administered more often in patients with postoperative urinary dysfunction (OR 17.67; 95% CI 2.44-127.7; p = 0.004). CONCLUSION: Shorter obstetric conjugate diameter might be a risk factor for incompleteness of total mesorectal excision. Anastomotic leakage seems to be influenced more by clinical factors such as anemia rather than pelvic dimensions. Further studies have to prove the influence of pelvic diameter on local recurrence of rectal cancer after LAR.


Subject(s)
Digestive System Surgical Procedures/methods , Pelvis/pathology , Pelvis/surgery , Rectal Neoplasms/surgery , Aged , Anastomotic Leak/etiology , Digestive System Surgical Procedures/adverse effects , Female , Humans , Imaging, Three-Dimensional , Male , Multivariate Analysis , Organ Size , Pelvis/diagnostic imaging , Rectal Neoplasms/diagnostic imaging , Regression Analysis , Risk Factors , Tomography, X-Ray Computed , Treatment Outcome
4.
Phys Med Biol ; 61(16): 5956-72, 2016 08 21.
Article in English | MEDLINE | ID: mdl-27435044

ABSTRACT

This paper demonstrates that optimization strategies derived from the field of compressed sensing (CS) improve computational performance in inverse treatment planning (ITP) for high-dose-rate (HDR) brachytherapy. Following an approach applied to low-dose-rate brachytherapy, we developed a reformulation of the ITP problem with the same mathematical structure as standard CS problems. Two greedy methods, derived from hard thresholding and subspace pursuit are presented and their performance is compared to state-of-the-art ITP solvers. Applied to clinical prostate brachytherapy plans speed-up by a factor of 56-350 compared to state-of-the-art methods. Based on a Wilcoxon signed rank-test the novel method statistically significantly decreases the final objective function value (p < 0.01). The optimization times were below one second and thus planing can be considered as real-time capable. The novel CS inspired strategy enables real-time ITP for HDR brachytherapy including catheter optimization. The generated plans are either clinically equivalent or show a better performance with respect to dosimetric measures.


Subject(s)
Brachytherapy/methods , Catheters/standards , Prostatic Neoplasms/radiotherapy , Radiometry/methods , Radiotherapy Planning, Computer-Assisted/methods , Humans , Male , Radiotherapy Dosage
5.
Chirurg ; 87(1): 47-55, 2016 Jan.
Article in German | MEDLINE | ID: mdl-25971607

ABSTRACT

INTRODUCTION: Incisional hernias are one of the the most frequent complications in visceral surgery and incisional hernia repair has a relevant complication rate. Therefore, there have to be solid indications before carrying out incisional hernia repair. To date, there is a lack of evidence concerning the correct indications for surgical repair of incisional hernias. The AWARE trial compares watchful waiting to surgical repair of incisional hernias. MATERIAL AND METHODS: The AWARE trial is a prospective randomized multicenter trial. Patients with asymptomatic or oligosymptomatic incisional hernia are randomized into the watchful waiting or the surgical repair group with a follow-up of 2 years. The primary endpoint is pain during normal activities due to the hernia or the hernia repair after 2 years measured on the hernia-specific surgical pain scale (SPS). RESULTS: In this study 36 centers are participating throughout Germany, more than 1600 patients had been screened up to 31 December 2014 and 234 (14.6%) of the screened patients could be recruited. CONCLUSION: The AWARE study will provide evidence concerning the two therapeutic options of watchful waiting and surgical repair of incisional hernia.


Subject(s)
Incisional Hernia/surgery , Watchful Waiting , Evidence-Based Medicine , Follow-Up Studies , Germany , Humans , Incisional Hernia/diagnosis , Incisional Hernia/etiology , Pain Measurement , Postoperative Complications/diagnosis , Postoperative Complications/etiology , Postoperative Complications/surgery , Prospective Studies , Quality of Life
6.
Phys Med Biol ; 60(6): 2179-94, 2015 Mar 21.
Article in English | MEDLINE | ID: mdl-25683684

ABSTRACT

This work discusses a novel strategy for inverse planning in low dose rate brachytherapy. It applies the idea of compressed sensing to the problem of inverse treatment planning and a new solver for this formulation is developed. An inverse planning algorithm was developed incorporating brachytherapy dose calculation methods as recommended by AAPM TG-43. For optimization of the functional a new variant of a matching pursuit type solver is presented. The results are compared with current state-of-the-art inverse treatment planning algorithms by means of real prostate cancer patient data. The novel strategy outperforms the best state-of-the-art methods in speed, while achieving comparable quality. It is able to find solutions with comparable values for the objective function and it achieves these results within a few microseconds, being up to 542 times faster than competing state-of-the-art strategies, allowing real-time treatment planning. The sparse solution of inverse brachytherapy planning achieved with methods from compressed sensing is a new paradigm for optimization in medical physics. Through the sparsity of required needles and seeds identified by this method, the cost of intervention may be reduced.


Subject(s)
Algorithms , Brachytherapy/methods , Radiotherapy Planning, Computer-Assisted/methods , Humans , Male , Prostatic Neoplasms/radiotherapy , Radiotherapy Dosage
7.
Scand J Med Sci Sports ; 19(5): 731-9, 2009 Oct.
Article in English | MEDLINE | ID: mdl-18627556

ABSTRACT

The purpose of this study was to examine weight concerns, dieting, body dissatisfaction as well as eating behavior of German high school athletes and to compare disordered eating behavior of these athletes with regular high school students. Five hundred and seventy-six young athletes of Elite Sports Schools in the German state of Thuringia and a reference group consisting of 291 non-athletes from regular high schools completed a questionnaire regarding eating behavior and attitudes, dietary history, body image and demographics. The Eating Attitude Test was used to measure disordered eating. Athletes did not show a higher frequency of disordered eating than non-athletes. A binary logistic regression analysis revealed that gender and dietary experience, but not group (athletes vs non-athletes), were significant predictors of disordered eating. It can be concluded that dietary experience and female gender proved to be important risk factors of disordered eating. Participation in sports seems to be protective for developing serious eating problems, especially in girls. Potentially, regular monitoring of athletic performance by coaches might be a reason for this finding.


Subject(s)
Athletes , Body Image , Diet Fads , Feeding and Eating Disorders/epidemiology , Adolescent , Attitude to Health , Female , Germany/epidemiology , Humans , Logistic Models , Male , Risk Factors , Surveys and Questionnaires
8.
Curr Top Microbiol Immunol ; 293: 73-87, 2005.
Article in English | MEDLINE | ID: mdl-15981476

ABSTRACT

Despite great interest in CD4+ CD25+ suppressor T cells, many of the fundamental properties of these cells remain enigmatic. This is in part due to experimental limitations inherent to the study of polyclonal suppressor T cells, and the extensive use of in vitro assays. This review article intends to outline recent advances in our understanding of the biology of suppressor T cells that have emerged from the analysis of T cell receptor (TCR) transgenic models. Several laboratories have taken advantage of model systems in which suppressor T cells of defined antigen-specificity are naturally selected in order to characterize the selection and behavior of these cells in vivo. In addition to providing valuable insights into the mechanism of differentiation of suppressor T cells, these systems now offer new possibilities for understanding the mode of action of suppressor T cells. For example, adoptive transfer of small numbers of ex vivo isolated TCR transgenic suppressor T cells allows for the visualization of the fate of such cells when confronted with cognate antigen in a quasi-normal, nonlymphopenic environment. Characteristic features of the currently available TCR transgenic models of suppressor T cells will be highlighted, and particular issues pertaining to the differentiation, function, and homeostasis of this T cell subset that have emerged from these models will be discussed.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , Receptors, Interleukin-2/immunology , T-Cell Antigen Receptor Specificity , Animals , Animals, Genetically Modified , Clonal Anergy , Humans , Lymphopoiesis , Receptors, Antigen, T-Cell/genetics , T-Cell Antigen Receptor Specificity/genetics , T-Lymphocyte Subsets/immunology , T-Lymphocytes, Regulatory/immunology , Thymus Gland/cytology , Thymus Gland/immunology
9.
Article in German | MEDLINE | ID: mdl-10803231

ABSTRACT

Two exemplary investigations with different questions were carried out in Munich and Stuttgart by sampling bio-aerosols due to and during the collection and emptying of different types of waste bins. The emissions were regarded qualitatively and quantitatively, in order to answer the question, whether and to which amount differences of bio-aerosol emissions occurred due to the kind of wastes collected. The lowest emissions of airborne microorganisms were found during the collection of the paper waste fraction. In comparison, the amounts of them during the collection of unseparated household wastes as well as source separated bio-wastes and the remaining residual waste fraction were higher. Between the three latter, no significant differences could be found, only a tendency of higher values for the thermotolerant mould A. fumigatus during the collection of bio- and residual wastes was observed. Maybe this was caused by special features of the different sampling locations, but it could also be due to the longer collection intervals (bio- and residual wastes were partially collected every two weeks, unseparated wastes every week).


Subject(s)
Air Microbiology , Garbage , Air Pollutants, Occupational/analysis , Colony Count, Microbial , Environmental Monitoring , Germany , Humans , Refuse Disposal
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