792 research outputs found
Topological insight into the non-Arrhenius mode hopping of semiconductor ring lasers
We investigate both theoretically and experimentally the stochastic switching
between two counter-propagating lasing modes of a semiconductor ring laser.
Experimentally, the residence time distribution cannot be described by a simple
one parameter Arrhenius exponential law and reveals the presence of two
different mode-hop scenarios with distinct time scales. In order to elucidate
the origin of these two time scales, we propose a topological approach based on
a two-dimensional dynamical system.Comment: 4 pages, 3 figure
Malignant Transformation of Giant Cell Tumor of Bone and the Association with Denosumab Treatment:A Radiology and Pathology Perspective
Objective. Malignancy in giant cell tumor of bone (mGCTB) is categorized as primary (concomitantly with conventional GCTB) or secondary (after radiotherapy or other treatment). Denosumab therapy has been suggested to play a role in the etiology of secondary mGCTB. In this case series from a tertiary referral sarcoma center, we aimed to find distinctive features for malignant transformation in GCTB on different imaging modalities. Furthermore, we assessed the duration of denosumab treatment and lag time to the development of malignancy. Methods. From a histopathology database search, 6 patients were pathologically confirmed as having initial conventional GCTB and subsequently with secondary mGCTB. Results. At the time of mGCTB diagnosis, 2 cases were treated with denosumab only, 2 with denosumab and surgery, 1 with multiple curettages and radiotherapy, and 1 with surgery only. In the 4 denosumab treated patients, the mean lag time to malignant transformation was 7 months (range 2-11 months). Imaging findings suspicious of malignant transformation related to denosumab therapy are the absence of fibro-osseous matrix formation and absent neocortex formation on CT, and stable or even increased size of the soft tissue component. Conclusion. In 4 patients treated with denosumab, secondary mGCTB occurred within the first year after initiation of treatment. Radiotherapy-associated mGCTB has a longer lag time than denosumab-associated mGCTB. Close clinical and imaging follow-up during the first months of denosumab therapy is key, as mGCTB tends to have rapid aggressive behavior, similar to other high-grade sarcomas. Nonresponders should be (re) evaluated for their primary diagnosis of conventional GCTB
Estimation of Muscle Mass in the Integrated Assessment of Patients on Hemodialysis
Assessment of muscle mass (MM) or its proxies, lean tissue mass (LTM) or fat-free mass (FFM), is an integral part of the diagnosis of protein-energy wasting (PEW) and sarcopenia in patients on hemodialysis (HD). Both sarcopenia and PEW are related to a loss of functionality and also increased morbidity and mortality in this patient population. However, loss of MM is a part of a wider spectrum, including inflammation and fluid overload. As both sarcopenia and PEW are amendable to treatment, estimation of MM regularly is therefore of major clinical relevance. Whereas, computer-assisted tomography (CT) or dual-energy X-ray absorptiometry (DXA) is considered a reference method, it is unsuitable as a method for routine clinical monitoring. In this review, different bedside methods to estimate MM or its proxies in patients on HD will be discussed, with emphasis on biochemical methods, simplified creatinine index (SCI), bioimpedance spectroscopy (BIS), and muscle ultrasound (US). Body composition parameters of all methods are related to the outcome and appear relevant in clinical practice. The US is the only parameter by which muscle dimensions are measured. BIS and SCI are also dependent on either theoretical assumptions or the use of population-specific regression equations. Potential caveats of the methods are that SCI can be influenced by residual renal function, BIS can be influenced by fluid overload, although the latter may be circumvented by the use of a three-compartment model, and that muscle US reflects regional and not whole body MM. In conclusion, both SCI and BIS as well as muscle US are all valuable methods that can be applied for bedside nutritional assessment in patients on HD and appear suitable for routine follow-up. The choice for either method depends on local preferences. However, estimation of MM or its proxies should always be part of a multidimensional assessment of the patient followed by a personalized treatment strategy
Нарративное интервью в исследовании катамнеза внутренней картины болезни при шизофрении (клинико-психологический аспект)
Представлены особенности проведения клинического нарративного интервью как значимого метода в психодиагностике внутренней картины болезни (ВКБ) в катамнезе у больных шизофренией. Проведено комплексное психоанамнестическое, психодиагностическое, патоперсонологическое обследование больных параноидной шизофренией. Сформулированы стратегии и тактики проведения нарративного интервью с целью выявления особенностей их ВКБ.Наведено особливості проведення клінічного наративного інтерв'ю як визначального методу в психодіагностиці внутрішньої картини хвороби (ВКХ) у катамнезі у хворих на шизофренію. Проведено комплексне психоанамнестичне, психодіагностичне, патоперсонологічне обстеження хворих на параноїдну шизофренію. Сформульовано стратегії і тактики проведення наративного інтерв'ю з метою виявлення особливостей їх ВКХ.The peculiarities of clinical narrative interview as a significant method in psychodagnosis of the disease inner picture (DIP) in the history of patients with schizophrenia are presented. Complex psychoanamnestic, psychodiagnostic, pathopersonological investigation of patients with paranoid schizophrenia was performed. The strategies and tactics of narrative interview with the purpose to reveal DIP peculiarities were formulated
Inflammation and premature aging in advanced chronic kidney disease
Systemic inflammation in end-stage renal disease (ESRD) is an established risk factor for mortality and a catalyst for other complications which are related to a premature aging phenotype, including muscle wasting, vascular calcification and other forms of premature vascular disease, depression, osteoporosis and frailty. Uremic inflammation is also mechanistically related to mechanisms involved in the aging process, such as telomere shortening, mitochondrial dysfunction, and altered nutrient sensing, which can have direct effect on cellular and tissue function. In addition to uremia-specific causes such as abnormalities in the phosphate- Klotho axis, there are remarkable similarities between the pathophysiology of uremic inflammation and so-called "inflammaging" in the general population. Potentially relevant, but still somewhat unexplored in this respect are abnormal or misplaced protein structures as well as abnormalities in tissue homeostasis, which evoke danger signals through damage associated molecular patters (DAMPS) as well as the senescence associated secretory phenotype (SASP). Systemic inflammation, in combination with the loss of kidney function, can impair the resilience of the body to external and internal stressors by reduced functional and structural tissue reserve, and by impairing normal organ crosstalk, thus providing an explanation for the greatly increased risk of homeostatic breakdown in this population. In this review, the relation between uremic inflammation and a premature aging phenotype, as well as potential causes and consequences are discussed
Long-term outcomes of slipped capital femoral epiphysis treated with in situ pinning
PURPOSE: Slipped capital femoral epiphysis (SCFE) is the commonest hip disorder in adolescents. In situ pinning is commonly performed, yet lately there has been an increase in procedures with open reduction and internal fixation. These procedures, however, are technically demanding with relatively high complication rates and unknown long-term outcomes. Nevertheless, reports on long-term results of in situ fixation are not equivocal. This study evaluates the possible higher risk of worse outcome after in situ pinning of SCFE. METHODS: All patients treated for SCFE with in situ fixation between 1980 and 2002 in four different hospitals were asked to participate. Patients were divided into three groups, based on severity of the slip. Patients were invited to the outpatient clinic for physical examination and X-rays, and to fill out the questionnaires HOOS, EQ5D, and SF36. ANOVA and chi-squared tests were used to analyze differences between groups. RESULTS: Sixty-one patients with 78 slips filled out the questionnaires. Patients with severe slips had worse scores on HOOS, EQ5D, and SF36. 75 % of patients with severe slips had severe osteoarthritis, compared to 2 % of mild and 11 % of moderate slips. CONCLUSION: Hips with mild and moderate SCFE generally had good functional and radiological outcome at a mean follow-up of 18 years, and for these hips there seems to be no indication for open procedures. However, severe slips have a significantly worse outcome, and open reduction and internal fixation could therefore be considered
Encouraging survival rates in patients with acute myocardial infarction treated with an intra-aortic balloon pump
Objective To evaluate a 30-day and long-term outcome of patients with acute myocardial infarction (AMI) treated with intra-aortic balloon pump (IABP) counterpulsation and to identify predictors of a 30-day and long-term all-cause mortality. Methods Retrospective cohort study of 437 consecutive AMI patients treated with IABP between January 1990 and June 2004. A Cox proportional hazards model was used to identify predictors of a 30-day and long-term all-cause mortality. Results Mean age of the study population was 61±11 years, 80% of the patients were male, and 68% had cardiogenic shock. Survival until IABP removal after successful haemodynamic stabilisation was 78% (n=341). Cumulative 30-day survival was 68%. Median follow-up was 2.9 years (range, 6 months to 15 years). In patients who survived until IABP removal, cumulative 1-, 5-, and 10-year survival was 75%
Unraveling the heterogeneity of sarcoma survivors’ health-related quality of life regarding primary sarcoma location: Results from the Survsarc study
Simple SummarySarcomas are a rare group of heterogenous tumors that can develop anywhere in the body. Currently, studies on health-related quality of life (HRQoL) focus on sarcomas of the arm and leg or have too small sample sizes to examine the heterogeneity between different sarcoma locations, leading to limited insight into HRQoL of survivors with specific sarcoma locations. The aim of this study was to assess differences in HRQoL and examine treatment-specific HRQoL issues per sarcoma location. We found, in a population of 1099 sarcoma survivors, different patterns of HRQoL according to primary sarcoma location and a high number of additional, unique treatment-specific HRQoL issues per location, which were not captured with the general HRQoL questionnaire used in cancer patients. This indicates that the currently used HRQoL measures are too generic to capture all sarcoma-related issues, emphasizing the necessity for a comprehensive sarcoma-specific HRQoL measurement strategy.Sarcoma patients experience physical and psychological symptoms, depending on age of onset, subtype, treatment, stage, and location of the sarcoma, which can adversely affect patients' health-related quality of life (HRQoL). This study aimed to unravel the heterogeneity of sarcoma survivors' HRQoL regarding primary sarcoma location. A cross-sectional study was conducted among Dutch sarcoma survivors (N = 1099) aged >= 18, diagnosed 2-10 years ago. Primary sarcoma locations were head and neck, chest, abdominal including retroperitoneal, pelvis including urogenital organs, axial skeleton, extremities (upper and lower), breast, skin and other locations. The European Organization for Research and Treatment of Cancer-Quality of Life Questionnaire (EORTC QLQ)-C30 was used to measure HRQoL accompanied by treatment-specific HRQoL questions. Sociodemographic and clinical characteristics were collected from the Netherlands Cancer Registry. Axial skeleton sarcomas had the lowest functioning levels and highest symptoms compared to other locations. Skin sarcomas had the highest functioning levels and lowest symptoms on most scales. Bone sarcomas scored worse on several HRQoL domains compared to soft tissue sarcomas. High prevalence of treatment-specific HRQoL issues were found per location. In conclusion, sarcomas can present everywhere, which is reflected by different HRQoL outcomes according to primary sarcoma location. The currently used HRQoL measure lacks treatment-specific questions and is too generic to capture all sarcoma-related issues, emphasizing the necessity for a comprehensive sarcoma-specific HRQoL measurement strategy.</p
Early childhood infections and body mass index in adolescence
BACKGROUND: The incidence of childhood overweight and obesity is rising. It is hypothesized that infections in early childhood are associated with being overweight. This study investigated the association between the number of symptomatic infections or antibiotic prescriptions in the first 3 years of life and body mass index (BMI) in adolescence. SUBJECTS: The current study is part of the Prevention and Incidence of Asthma and Mite Allergy population-based birth cohort study. Weight and height were measured by trained research staff at ages 12 and 16 years. The 3015 active participants at age 18 years were asked for informed consent for general practitioner (GP) data collection and 1519 gave written informed consent. Studied exposures include (1) GP-diagnosed infections, (2) antibiotic prescriptions, and (3) parent-reported infections in the first 3 years of life. Generalized estimating equation analysis was used to determine the association between each of these exposures and BMI z-score. RESULTS: Exposure data and BMI measurement in adolescence were available for 622 participants. The frequencies of GP-diagnosed infections and antibiotic prescriptions were not associated with BMI z-score in adolescence with estimates being 0.14 (95% CI -0.09-0.37) and 0.10 (95% CI -0.14-0.34) for the highest exposure categories, respectively. Having ≥6 parent-reported infections up to age 3 years was associated with a 0.23 (95% CI 0.01-0.44) higher BMI z-score compared to <2 parent-reported infections. CONCLUSIONS: For all infectious disease measures an increase in BMI z-score for the highest childhood exposure to infectious disease was observed, although only statistically significant for parent-reported infections. These results do not show an evident link with infection severity, but suggest a possible cumulative effect of repeated symptomatic infections on overweight development
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