A geoökológia és a geoökológiai térképezés néhány elvi és gyakorlati kérdése

The geographical environment can be investigated from several aspects: - in the biological (ecological) approach emphasis is put on the biotic factors of the environment or on the structure itself; - in the geographical approach research concentrates on the abiotic factors and functions; and - the technological or planning trend focuses the analysis on the economical-technical background of impacts. To distinguish between the first two trends and the related disciplines, the terms (bio) ecology and geoecology are in use. The two concepts differ in handling the role of abiogenic and biogenic factors. In the past decade there was an intension to define geoecology as the study of abiotic factors and of issues concerning the functioning of the physical environment, while landscape ecology investigates the biogenic factors and problems of spatial organisation, structure. Several authors, however, use these concepts interchangeably. The problem is more complicated than that. On the other hand, the concept landscape is narrower or different from that covered by landscape ecology. The latter studies the arrangement of the ecosystem and the flows of matter and energy between its componensts. Here the question is not simply whether or to what extent man-made elements are included in landscape functioning. On the other hand, there is a significant difference between the landscape and the (physical) geographical environment – the true carrier of system properties. This difference of contents was clarified by S. Marosi (1981). In his opinion, the landscape consists of geotopes (naturally including biotopes), while the (geographical) environment is built up of ecotopes and – as a spatial unit – from ecochores. It is the activity of the society related to the socio- or econotopes that makes the geotopes exotopes. In the Marosi model the relationship between landscape and environment is clearly defined. No similar is applied in either the German or in the English-language literature. At the same time, the often used term landscape ecology is difficult to interpret from this standpoint, since they are almost mutually exclusive categories. Spatial pattern is often emphasised in the investigation of the landscape, of the concrete environment and the implications for functioning are neglected, the various ’topes’ are not regarded as aspects of functioning. In the same manner it would be a mistake to restrict the study only to the biogenic or to the abiogenic factors or to disregard functional or system properties. In our opinion – after the scheme by H. Leser (1984) – the German and English schools and the Hungarian views can be reconciled as shown in Fig. l. The size of the landscape ecology frame in the figure may change with various approaches and even it location may vary with the emphasis being on spatiality (like in the Russian literature) or on systems approach (like in the concept of English speaking researchers). Although it contradicts rigid delimitations, geoecology – among others for the above reasons – should cover the analysis of biotic factors too (hence is the uncertainty of delimitation), since they reflect the joint impact of abiotic factors and also point to human influences. Hopefully, the series of examples in the paper call attention to the flexibility of categories. There is communication between them, e.g. geoecology may also reveal structural properties and landscape ecology may answer functional questions of the physical environment. In this respect, the distinction between the two concepts may seem groundless. In our opinion, the in dependent treatment of geoecology separate from landscape ecology, a discipline with more traditions and broader contents, can be justified by the increasing importance of issues of environmental functioning, assessment of the partial potentials of the physical environment (i.e. landscape capacity controlled by landscape budget), data aquisition from field measurements and other practical requirements. The principles of geoecological mapping outlined here (Figure 2) reach beyond the 1:25,000 scale geoecological mapping in Germany, both in methodology and in objective4s. It seemed necessary to apply – in addition to the conventional field surveys, mapping and laboratory techniques – GIS for data storage and processing and for the regional extension of results automated aerial photo interpretation (with scanner) and other remote sensing methods. Although complex systems (such as the landscape) can only be fragmented in a holistic approach, efficiency required the application of a GIS. In the paper three examples are used to illustrate the opportunities to geoecological mapping. The first of them concerns the reclamation or optimal utilisation of surfaces partially used for agricultural purposes, while the second identifies areas affected by hazards, soil erosion, and the third deals with physical loadability through recreation

Apoptosis induction and inhibition of cellular proliferation by angiotensin II: possible implication and perspectives

The renin-angiotensin system plays a pivotal role in the regulation of fluid, electrolyte metabolism and blood pressure. Molecular cloning and pharmacological studies have defined two major classes of Angiotensin II (Ang II) receptors, designated AT1 and AT2. Recently, it has been well recognized that Ang II, beside its classical physiological actions, is a profibrogenic peptide and displays characteristics of a growth factor. The emerging picture suggests that angiotensin receptor subtypes exert opposing features in many aspects of their biological function, most importantly in cellular growth and proliferation. Accordingly, the proliferative and/or growth-promoting effects of Ang II are thought to be mediated by AT1 receptor, whereas the AT2 receptor subtype may have growth-inhibitory properties. The novel finding that Ang II is able to induce apoptosis by AT 2 receptors in diverse cell types is of great scientific interest, as recent studies revealed a role for apoptosis as a deliberate form of cell death in the pathogenesis of various cardiovascular diseases such as heart failure and vascular remodeling. Furthermore apoptotic cell death might occur during the development of progressive glomerulosclerosis. It is tempting to speculate that autocrine-paracrine vasoactive substances such as Ang II might regulate these apoptotic processes during pathogenic conditions

Sociodemographic factors and patient perceptions are associated with attitudes to kidney transplantation among haemodialysis patients

Background. Treatment decisions made by patients with chronic kidney disease are crucial in the renal transplantation process. These decisions are influenced, amongst other factors, by attitudes towards different treatment options, which are modulated by knowledge and perceptions about the disease and its treatment and many other subjective factors. Here we study the attitude of dialysis patients to renal transplantation and the association of sociodemographic characteristics, patient perceptions and experiences with this attitude. Methods. In a cross-sectional study, all patients from eight dialysis units in Budapest, Hungary, who were on haemodialysis for at least 3 months were approached to complete a self-administered questionnaire. Data collected from 459 patients younger than 70 years were analysed in this manuscript. Results. Mean age of the study population was 53 +/- 12 years, 54% were male and the prevalence of diabetes was 22%. Patients with positive attitude to renal transplantation were younger (51 +/- 11 versus 58 +/- 11 years), better educated, more likely to be employed (11% versus 4%) and had prior transplantation (15% versus 7%)(P < 0.05 for all). In a multivariate model, negative patient perceptions about transplantation, negative expectations about health outcomes after transplantation and the presence of fears about the transplant surgery were associated, in addition to incre- asing age, with unwillingness to consider transplantation. Conclusions. Negative attitudes to renal transplantation are associated with potentially modifiable factors. Based on this we suggest that it would be necessary to develop standardized, comprehensible patient information systems and personalized decision support to facilitate modality selection and to enable patients to make fully informed treatment decisions

Simple, readily available clinical indices predict early and late mortality among patients with ANCA-associated vasculitis

BACKGROUND: The early identification of patients with ANCA-associated vasculitis (AAV) who are at increased risk for inferior clinical outcome at the time of diagnosis might help to optimize the immunosuppressive therapy. In this study we wanted to determine the predictive value of simple clinical characteristics, which may be applicable for early risk-stratification of patients with AAV. METHODS: We retrospectively analyzed the outcome of 101 consecutive patients with AAV receiving a protocolized immunosuppressive therapy. Baseline Birmingham Vasculitis Activity Score (BVAS) and non-vasculitic comorbidities were computed, then predictors of early (90 days) mortality, infectious death, relapse and end stage kidney disease (ESKD) were evaluated. RESULTS: The baseline comorbidity score independently predicted early mortality (HR 1.622, CI 1.006-2.614), and showed association with infectious mortality (HR 2.056, CI 1.247-3.392). Patients with BVAS at or above median (=21) had worse early mortality in univariable analysis (HR 3.57, CI 1.039-12.243) (p = 0.031), and had more frequent relapses (p = 0.01) compared to patients with BVAS below median. CONCLUSIONS: Assessing baseline comorbidities, beside clinical indices characterizing the severity and extension of AAV, might help clinicians in risk-stratification of patients. Future prospective studies are needed to investigate whether therapies based on risk-stratification could improve both short term and long term survival

Spatial risk assessment of hydrological extremities : Inland excess water hazard, Szabolcs-Szatmár-Bereg Country, Hungary

Inland excess water hazard was regionalized and digitally mapped using auxiliary spatial environmental information for a county in Eastern Hungary. Quantified parameters representing the effect of soil, geology, groundwater, land use and hydrometeorology on the formulation of inland excess water were defined and spatially explicitly derived. The complex role of relief was characterized using multiple derivatives computed from a DEM. Legacy maps displaying inland excess water events were used as a reference dataset. Regression kriging was applied for spatial inference with the correlation between environmental factors and inundation determined using multiple linear regressions. A stochastic factor derived through kriging the residual was added to the regression results,thus producing the final inundation hazard map. This may be of use for numerous landrelated activities

Association of symptoms of insomnia and sleep parameters among kidney transplant recipients

Objective: Insomnia complaints are frequent among kidney transplant (kTx) recipients and are associated with fatigue, depression, lower quality of life and increased morbidity. However, it is not known if subjective insomnia symptoms are associated with objective parameters of sleep architecture. Thus, we analyze the association between sleep macrostructure and EEG activity versus insomnia symptoms among kTx recipients. Methods: Participants (n1 = 100) were selected from prevalent adult transplant recipients (n0 = 1214) followed at a single institution. Insomnia symptoms were assessed by the Athens Insomnia Scale (AIS) and standard overnight polysomnography was performed. In a subgroup of patients (n2 = 56) sleep microstructure was also analyzed with power spectral analysis. Results: In univariable analysis AIS score was not associated with sleep macrostructure parameters (sleep latency, total sleep time, slow wave sleep, wake after sleep onset), nor with NREM and REM beta or delta activity in sleep microstructure. In multivariable analysis after controlling for covariables AIS score was independently associated with the proportion of slow wave sleep (β = 0.263; CI: 0.026–0.500) and REM beta activity (β = 0.323; CI = 0.041–0.606) (p < 0.05 for both associations). Conclusions: Among kTx recipients the severity of insomnia symptoms is independently associated with higher proportion of slow wave sleep and increased beta activity during REM sleep but not with other parameters sleep architecture. The results suggest a potential compensatory sleep protective mechanism and a sign of REM sleep instability associated with insomnia symptoms among this population

Sleep disorders, depressive symptoms and health-related quality of life-a cross-sectional comparison between kidney transplant recipients and waitlisted patients on maintenance dialysis

BACKGROUND: Kidney transplantation is believed to improve health-related quality of life (HRQoL) of patients requiring renal replacement therapy (RRT). Recent studies suggested that the observed difference in HRQoL between kidney transplant recipients (Tx) vs patients treated with dialysis may reflect differences in patient characteristics. We tested if Tx patients have better HRQoL compared to waitlisted (WL) patients treated with dialysis after extensive adjustment for covariables. METHODS: Eight hundred and eighty-eight prevalent Tx patients followed at a single outpatient transplant clinic and 187 WL patients treated with maintenance dialysis in nine dialysis centres were enrolled in this observational cross-sectional study. Data about socio-demographic and clinical parameters, self-reported depressive symptoms and the most frequent sleep disorders assessed by self-reported questionnaires were collected at enrollment. HRQoL was assessed by the Kidney Disease Quality of Life Questionnaire. RESULTS: Patient characteristics were similar in the Tx vs WL groups: the proportion of males (58 vs 60%), mean +/- SD age (49 +/- 13 vs 49 +/- 12) and proportion of diabetics (17 vs 18%), respectively, were all similar. Tx patients had significantly better HRQoL scores compared to the WL group both in generic (Physical function, General health perceptions, Energy/fatigue, Emotional well-being) and in kidney disease-specific domains (Symptoms/problems, Effect- and Burden of kidney disease and Sleep). In multivariate regression models adjusting for clinical and socio-demographic characteristics, sleep disorders and depressive symptoms, the modality of RRT (WL vs Tx) remained independently associated with three (General health perceptions, Effect- and Burden of kidney disease) out of the eight HRQoL dimensions analysed. CONCLUSIONS: Kidney Tx recipients have significantly better HRQoL compared to WL dialysis patients in some, but not all, dimensions of quality of life after accounting for differences in patient characteristics. Utilizing multidimensional disease-specific questionnaires will allow better understanding of treatment, disease and patient-related factors potentially affecting quality of life in patients with chronic medical conditions

Age-dependent parathormone levels and different CKD-MBD treatment practices of dialysis patients in Hungary - results from a nationwide clinical audit

BACKGROUND: Achieving target levels of laboratory parameters of bone and mineral metabolism in chronic kidney disease (CKD) patients is important but also difficult in those living with end-stage kidney disease. This study aimed to determine if there are age-related differences in chronic kidney disease-mineral and bone disorder (CKD-MBD) characteristics, including treatment practice in Hungarian dialysis patients. METHODS: Data were collected retrospectively from a large cohort of dialysis patients in Hungary. Patients on hemodialysis and peritoneal dialysis were also included. The enrolled patients were allocated into two groups based on their age (=65 years). Characteristics of the age groups and differences in disease-related (epidemiology, laboratory, and treatment practice) parameters between the groups were analyzed. RESULTS: A total of 5008 patients were included in the analysis and the mean age was 63.4+/-14.2 years. A total of 47.2% of patients were women, 32.8% had diabetes, and 11.4% were on peritoneal dialysis. Diabetes (37.9% vs 27.3%), bone disease (42.9% vs 34.1%), and soft tissue calcification (56.3% vs 44.7%) were more prevalent in the older group than the younger group (p<0.001 for all). We found an inverse relationship between age and parathyroid hormone (PTH) levels (p<0.001). Serum PTH levels were lower in patients with diabetes compared with those without diabetes below 80 years (p<0.001). Diabetes and age were independently associated with serum PTH levels (interaction: diabetes x age groups, p=0.138). Older patients were more likely than younger patients to achieve laboratory target ranges for each parameter (Ca: 66.9% vs 62.1%, p<0.001; PO4: 52.6% vs 49.2%, p<0.05; and PTH: 50.6% vs 46.6%, p<0.01), and for combined parameters (19.8% vs 15.8%, p<0.001). Older patients were less likely to receive related medication than younger patients (66.9% vs 79.7%, p<0.001). CONCLUSIONS: The achievement of laboratory target ranges for bone and mineral metabolism and clinical practice in CKD depends on the age of the patients. A greater proportion of older patients met target criteria and received less medication compared with younger patients