The Mathematical Aspects of Research Retrospective and Geographical Processes Settling in the Region

Розглядаються питання застосування низки простих і складних ретроспективно-географічних поселенських показників, які параметризують процеси виникнення поселень і заселення певної території. Зокрема, наголошується на показнику ретроспективного заселення, поступовому потенціалі ланцюговості заселення, сумарній поселенській енергії території, історичних центрах та пунктах заселення, сумарному й інтегрованому поселенському потенціалові, параметричних коефіцієнтах заселення етапів (сім величин), показнику інтегрального поселення.The paper discusses the use of a series of simple and complex indicators of retrospective and geographical settlement, that parametrized processes of settlement and colonization a certain territory. The retrospective index of settlement, the gradual settling the potential of chain, the total settlement area of energy, historical centers and points of settlement, total settlement and integrated capabilities, and parametric coefficients settling stages (seven variables), the integral index of the settlement were focused

Retrospective methods to estimate radiation dose at the site of breast cancer development after Hodgkin lymphoma radiotherapy.

BACKGROUND: An increased risk of breast cancer following radiotherapy for Hodgkin lymphoma (HL) has now been robustly established. In order to estimate the dose-response relationship more accurately, and to aid clinical decision making, a retrospective estimation of the radiation dose delivered to the site of the subsequent breast cancer is required. METHODS: For 174 Dutch and 170 UK female patients with breast cancer following HL treatment, the 3-dimensional position of the breast cancer in the affected breast was determined and transferred onto a CT-based anthropomorphic phantom. Using a radiotherapy treatment planning system the dose distribution on the CT-based phantom was calculated for the 46 different radiation treatment field set-ups used in the study population. The estimated dose at the centre of the breast cancer, and a margin to reflect dose uncertainty were determined on the basis of the location of the tumour and the isodose lines from the treatment planning. We assessed inter-observer variation and for 47 patients we compared the results with a previously applied dosimetry method. RESULTS: The estimated median point dose at the centre of the breast cancer location was 29.75 Gy (IQR 5.8-37.2), or about 75% of the prescribed radiotherapy dose. The median dose uncertainty range was 5.97 Gy. We observed an excellent inter-observer variation (ICC 0.89 (95% CI: 0.74-0.95)). The absolute agreement intra-class correlation coefficient (ICC) for inter-method variation was 0.59 (95% CI: 0.37-0.75), indicating (nearly) good agreement. There were no systematic differences in the dose estimates between observers or methods. CONCLUSION: Estimates of the dose at the point of a subsequent breast cancer show good correlation between methods, but the retrospective nature of the estimates means that there is always some uncertainty to be accounted for

Kinetics of toluene degradation by toluene-oxidizing bacteria as a function of oxygen concentration, and the effect of nitrate

The kinetics of toluene degradation as a function of oxygen concentration were compared for six strains of toluene-oxidizing bacteria using initial rate assays. The effect of nitrate was also examined. Rates of degradation and the relative effect of oxygen on the degradation rate were correlated with the pathway for toluene oxidation. Strains which synthesize toluene dioxygenases, Pseudomonas putida F1, P. fluorescens CFS215, and Pseudomonas sp. strain W31, degraded toluene at significantly higher rates (151–166 nmol/mg per min) than strains synthesizing toluene monooxygenases, Burkholderia cepacia G4 (23 nmol/mg per min) and B. pickettii PKO1 (14 nmol/mg per min), or a methylmonooxygenase, P. putida PaW1 (12 nmol/mg per min). Rates declined 30–48% for the dioxygenase strains and 25% for PaW1 as the oxygen concentration was decreased from 240 to 50 ΜM, but declined less than 10% for G4 and PKO1. Nitrate enhanced toluene degradation by the denitrifying strains PKO1 and W31 at oxygen concentrations below 30 ΜM, but had no significant effect on any of the other strains. Biphasic kinetics were observed for all of the strains, with double-reciprocal plots of the data exhibiting an inflection point at a ‘critical oxygen concentration’ between 20 and 30 ΜM. Below this concentration, the rate of toluene degradation was inhibited to a greater extent than predicted by the kinetic data for higher oxygen concentrations. For the denitrifying strains PKO1 and W31, however, monophasic kinetics were observed when nitrate was provided as an alternative electron acceptor. These observations suggest that biphasic kinetics result when rates of toluene degradation are limited by the availability of electron acceptor at the critical oxygen concentration, and that this limitation is overcome by denitrifying strains able to respire nitrate. Taken together, our findings suggest that the synthesis of monooxygenases and the ability to denitrify represent independent adaptations for toluene utilization in low oxygen environments. Moreover, these data support the use of nitrate in mixed electron acceptor strategies for the bioremediation of contaminated aquifers, as well as the targeted use of monooxygenase and dioxygenase strains in settings in which their physiological traits can be best exploited.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74870/1/j.1574-6941.1997.tb00387.x.pd

Substance-Related Health Problems during Rave Parties in the Netherlands (1997–2008)

The objective of this study was to describe a 12-year (1997–2008) observation of substance-related incidents occurring at rave parties in the Netherlands, including length of visits to first-aid stations, substances used, and severity of the incidents. During rave parties, specifically trained medical and paramedical personnel staffed first aid stations. Visitors were diagnosed and treated, and their data were recorded using standardized methods. During the 12-year period with 249 rave parties involving about 3,800,000 visitors, 27,897 people visited a first aid station, of whom 10,100 reported having a substance-related problem. The mean age of these people was 22.3+/−5.4 years; 52.4% of them were male. Most (66.7%) substance-related problems were associated with ecstasy or alcohol use or both. Among 10,100 substance-related cases, 515 required professional medical care, and 16 of these cases were life threatening. People with a substance-related problem stayed 20 min at the first aid station, which was significantly longer than the 5 min that those without a substance-related health problem stayed. These unique data from the Netherlands identify a variety of acute health problems related to the use of alcohol, amphetamines, cannabis, cocaine, ecstasy, and GHB. Although most problems were minor, people using GHB more often required professional medical care those using the other substances. We recommended adherence to harm and risk reduction policy, and the use of first aid stations with specially trained staff for both minor and serious incidents

Hospital variation and outcomes of simultaneous resection of primary colorectal tumour and liver metastases:a population-based study

BACKGROUND: The optimal treatment sequence for patients with synchronous colorectal liver metastases (CRLM) remains uncertain. This study aimed to assess factors associated with the use of simultaneous resections and impact on hospital variation. METHOD: This population-based study included all patients who underwent liver surgery for synchronous colorectal liver metastases between 2014 and 2019 in the Netherlands. Factors associated with simultaneous resection were identified. Short-term surgical outcomes of simultaneous resections and factors associated with 30-day major morbidity were evaluated. RESULTS: Of 2146 patients included, 589 (27%) underwent simultaneous resection in 28 hospitals. Simultaneous resection was associated with age, sex, BMI, number, size and bilobar distribution of CRLM, and administration of preoperative chemotherapy. More minimally invasive and minor resections were performed in the simultaneous group. Hospital variation was present (range 2.4%-83.3%) with several hospitals performing simultaneous procedures more and less frequently than expected. Simultaneous resection resulted in 13% 30-day major morbidity, and 1% mortality. ASA classification ≥3 was independently associated with higher 30-day major morbidity after simultaneous resection (aOR 1.97, CI 1.10-3.42, p = 0.018). CONCLUSION: Distinctive patient and tumour characteristics influence the choice for simultaneous resection. Remarkable hospital variation is present in the Netherlands

Population-based study on practice variation regarding preoperative systemic chemotherapy in patients with colorectal liver metastases and impact on short-term outcomes

Introduction: Definitions regarding resectability and hence indications for preoperative chemotherapy vary. Use of preoperative chemotherapy may influence postoperative outcomes. This study aimed to assess the variation in use of preoperative chemotherapy for CRLM and related postoperative outcomes in the Netherlands. Materials and methods: All patients who underwent liver resection for CRLM in the Netherlands between 2014 and 2018 were included from a national database. Case-mix factors contributing to the use of preoperative chemotherapy, hospital variation and postoperative outcomes were assessed using multivariable logistic regression. Postoperative outcomes were postoperative complicated course (PCC), 30-day morbidity and 30-day mortality. Results: In total, 4469 patients were included of whom 1314 patients received preoperative chemotherapy and 3155 patients did not. Patients receiving chemotherapy were significantly younger (mean age (+SD) 66.3 (10.4) versus 63.2 (10.2) p < 0.001) and had less comorbidity (Charlson scores 2+ (24% versus 29%, p = 0.010). Unadjusted hospital variation concerning administration of preoperative chemotherapy ranged between 2% and 55%. After adjusting for case-mix factors, three hospitals administered significantly more preoperative chemotherapy than expected and six administered significantly less preoperative chemotherapy than expected. PCC was 12.1%, 30-day morbidity was 8.8% and 30-day mortality was 1.5%. No association between preoperative chemotherapy and PCC (OR 1.24, 0.98–1.55, p = 0.065), 30-day morbidity (OR 1.05, 0.81–1.39, p = 0.703) or with 30-day mortality (OR 1.22, 0.75–2.09, p = 0.467) was found. Conclusion: Significant hospital variation in the use of preoperative chemotherapy for CRLM was present in the Netherlands. No association between postoperative outcomes and use of preoperative chemotherapy was found

Multidirectional Time-Dependent Effect of Sinigrin and Allyl Isothiocyanate on Metabolic Parameters in Rats

Sinigrin (SIN) and allyl isothiocyanate (AITC) are compounds found in high concentrations in Brassica family vegetables, especially in Brussels sprouts. Recently, they have been used as a nutrition supplement for their preventive and medicinal effect on some types of cancer and other diseases. In this research, nutritional significance of parent glucosinolate sinigrin 50 μmol/kg b. w./day and its degradation product allyl isothiocyanate 25 μmol/kg b. w./day and 50 μmol/kg b. w./day was studied by the evaluation of their influence on some parameters of carbohydrate and lipid metabolism in an animal rat model in vivo after their single (4 h) and 2 weeks oral administration. Additionally, the aim of this trial was to evaluate the direct action of AITC on basal and epinephrine-induced lipolysis in isolated rat adipocytes at concentration 1 μM, 10 μM and 100 μM in vitro. Sole AITC after 4 h of its ingestion caused liver triacylglycerols increment at both doses and glycaemia only at the higher dose. Multiple SIN treatment showed its putative bioconversion into AITC. It was found that SIN and AITC multiple administration in the same way strongly disturbed lipid and carbohydrate homeostasis, increasing esterified and total cholesterol, free fatty acids and lowering tracylglycerols in the blood serum. Additionally, AITC at both doses elevated insulinaemia and liver glycogen enhancement. The in vitro experiment revealed that AITC potentiated basal lipolysis process at 10 μM, and had stimulatory effect on epinephrine action at 1 μM and 10 μM. The results of this study demonstrated that the effect of SIN and AITC is multidirectional, indicating its impact on many organs like liver as well as pancreas, intestine in vivo action and rat adipocytes in vitro. Whilst consumption of cruciferous vegetables at levels currently considered “normal” seems to be beneficial to human health, this data suggest that any large increase in intake could conceivably lead to undesirable effect. This effect is potentiated with time of action of the examined compounds, whose influence is rather adverse for the majority of metabolic pathways (liver steatosis at short duration and insulinaemia, cholesterolaemia at long time treatment). Beneficial action of AITC concerned intensified hydrolysis of TG in the blood serum with a simultaneous lipolysis in adipocytes

Ethnic variation in validity of the estimated obesity prevalence using self-reported weight and height measurements

<p>Abstract</p> <p>Background</p> <p>We examined ethnic differences between levels of body mass index (BMI) based on self-reported and measured body height and weight and the validity of self-reports used to estimate the prevalence of obesity (BMI≥30 kg/m²) in Turkish, Moroccan, and Dutch people in the Netherlands. Furthermore, we investigated whether BMI levels and the prevalence of obesity in Turkish and Moroccan people with incomplete self-reports (missing height or weight) differ from those with complete self-reports.</p> <p>Methods</p> <p>Data on self-reported and measured height and weight were collected in a population-based survey among 441 Dutch, 414 Turks and 344 Moroccans aged 18 to 69 years in Amsterdam, the Netherlands in 2004. BMI and obesity were calculated from self-reported and measured height and weight.</p> <p>Results</p> <p>The difference between measured and estimated BMI was larger in Turkish and Moroccan women than in Dutch women, which was explained by the higher BMI of the Turkish and Moroccan women. In men we found no ethnic differences between measured and estimated BMI. Sensitivity to detect obesity was low and specificity was high. In participants with available self-reported and measured height and weight, self-reports produced a similar underestimation of the obesity prevalence in all ethnic groups. However, many obese Turkish and Moroccan women had incomplete self-reports, missing height or weight, resulting in an additional underestimation of the prevalence of obesity. Among men (all ethnicities) and Dutch women, the availability of height or weight by self-report did not differ between obese and non obese participants.</p> <p>Conclusions</p> <p>BMI based on self-reports is underestimated more by Turkish and Moroccan women than Dutch women, which is explained by the higher BMI of Turkish and Moroccan women. Further, in women, ethnic differences in the estimation of obesity prevalence based on self-reports do exist and are due to incomplete self-reports in obese Turkish and Moroccan women. In men, ethnicity is not associated with discrepancies between levels of BMI and obesity prevalence based on measurements and self-reports. Hence, our results indicate that using measurements to accurately determine levels of BMI and obesity prevalence in public health research seems even more important in Turkish and Moroccan migrant women than in other populations.</p