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- Author or Editor: S. László x
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Biodiversity is increasingly threatened by intensive agriculture, environmental pollution, extinction of natural habitats and several other factors. Several mammalian species including ungulates have disappeared or are threatened by extinction. However, ungulates play an important role both in the ecosystem and in the economy. In general, species or breeds are considered endangered if their population does not exceed 1,000 individuals. In these cases conservation programmes should be initiated in order to maintain or even increase their number. This review deals with the possibilities and limitations of assisted reproductive technologies (ART) in the conservation of ecologically valuable wild, rare and indigenous ungulates. The methods discussed here are artificial insemination, cryopreservation of semen and embryos, embryo recovery and transfer,in vitroproduction of embryos, as well as micromanipulation techniques including sperm injection, assisted hatching and cloning. Some of these procedures are already being exploited in the breeding of farm ungulates, but more basic information about the reproductive patterns of wild, rare and indigenous animal species is needed before the routine use of ARTs.
Szentes, Tamás: World Economics. Comparative Theories and Methods of International and Development Economics (Budapest: Akadémiai Kiadó, 2002, 462 pp.) Kozlov, Vladimir A. (ed. by E. McClarnand MacKinnon): Mass Uprisings in the USSR: Protest and Rebellion in the Post-Stalin Years (New York: Armonk and London: M. E. Sharpe, 2002, 351 pp.) Gilpin, Robert: Global Political Economy: Understanding the International Economic Order (Princeton: Princeton University Press, 2001, 423 pp.)
Abstract
The selectivity obtained in the aromatization of propane over Zn-ZSM-5-based catalysts (Si/Al nominal ratio = 35) increased from about 69% (carbon basis) to 74–91% when a second transition metal ion is introduced into the catalyst. The effect, previously reported for the case of Fe3+ ions, has now been shown to be more general and is seen also for the ions of chromium, cobalt or manganese. It is likely that these ions are present under aromatization conditions in a partially reduced state. H2/D2 isotope exchange rates show large enhancements on the reduced Fe-Zn/ZSM-5 and Co-Zn/ZSM-5 samples. This aspect of aromatization catalysis has not been reported before.
Az idősödés során jellemző genetikai és epigenetikai változások és a gammopátiák progressziója •
A myeloma multiplex az öregedés egyik arca lehet?
Age-related genetic and epigenetic changes and the progression of gammopathies?
Ebben a munkában bemutatásra kerül, hogy a tünetes myeloma multiplex (MM) betegség fokozatos kialakulásának lépéseiben számos hasonló genetikai és epigenetikai változás érhető tetten, mint a klinikai diagnózissal nem bíró, tehát egészséges, vagyis sikeres öregedés során. Az életkorral járó változásokra részben mint oki tényezőkre is tekinthetünk a gammopátiák progressziójában, vagy tekinthetjük őket többé-kevésbé független, párhuzamos sejtszintű történéseknek, melyek gyorsíthatják az MM kifejlődését. Az átfedő jelenségek miatt arra a következtetésre juthatunk, hogy indokolt oki tényezőként gondolni az öregedésre a MM progressziója/transzformációja során, hozzátéve, hogy az öregedési folyamatokra különösen érzékenyek a memória B-sejtek. A sejtszintű öregedés folyamatainak figyelembevétele az MGUS–MM-átmenetben ugyanakkor jó magyarázatot ad a myeloma diagnózisakor észlelt nagyszámú párhuzamos daganatsejtes klón jelenlétére. A sejtszintű öregedés ellen ható kutatások követése a klinikusok és a betegek számára is ajánlott, mert bővülő ismereteink körültekintő alkalmazásai mindinkább beépülhetnek a megelőzésbe, a progresszió lassításába, sőt akár a terápia részévé válhatnak.
Abstract
Elemental concentrations of P, S, Cl, K, Ca, Fe, Ni, Cu, Zn, Br, Rb have been determined in erythrocyte and blood plasma samples from normal and diabetic human pregnancies. Average values, the dependence of the concentrations on the time during gestation period, the correlation coefficients for pairs of elements as well as for the same elements in plasma and erythrocyte samples are given. A marked difference appeared in a number of cases between normal and diabetic pregancies.
Infection with fungal pathogens on wheat varieties with different levels of resistance was tested at ambient (NC, 390 ppm) and elevated (EC, 750 ppm) atmospheric CO2 levels in the phytotron. EC was found to affect many aspects of the plant-pathogen interaction. Infection with most fungal diseases was usually found to be promoted by elevated CO2 level in susceptible varieties. Powdery mildew, leaf rust and stem rust produced more severe symptoms on plants of susceptible varieties, while resistant varieties were not infected even at EC. The penetration of Fusarium head blight (FHB) into the spike was delayed by EC in Mv Mambo, while it was unaffected in Mv Regiment and stimulated in Mv Emma. EC increased the propagation of FHB in Mv Mambo and Mv Emma. Enhanced resistance to the spread of Fusarium within the plant was only found in Mv Regiment, which has good resistance to penetration but poor resistance to the spread of FHB at NC. FHB infection was more severe at EC in two varieties, while the plants of Mv Regiment, which has the best field resistance at NC, did not exhibit a higher infection level at EC.The above results suggest that breeding for new resistant varieties will remain a useful means of preventing more severe infection in a future with higher atmospheric CO2 levels.
Factors affecting the cellulase production of Aspergillus niger using sugar cane bagasse as carbon source were investigated. The highest enzyme activities were obtained, when the culture medium was supplemented with 0.133% tryptone as nitrogen source. The rate of cellulase production was considerably increased when 0.5% Tween 60 was added to the production medium. For FPA and b-glucosidase production pH 5.0, while for CMC-ase pH 5.5 was found to be optimal. The highest cellulase activities were obtained at 30 °C and 300 r.p.m. The highest saccharification degree was achieved, when alkali treated rice straw was used as substrate. The main objective of the present study was to examine the possibilities of lactic acid production from alkali treated rice straw using simultaneous saccharification and fermentation technique with T. koningii cellulases and L. delbrueckii. The highest conversion of cellulose was obtained using 6% alkaline treated rice straw supplemented with 1.2 mg enzyme/g substrate at pH 4.8 and 45 °C.
Abstract
The South African Ministry of Health has recognized experiences of care as key to strengthen patient-centred care. This case study aims to measure patient-reported experiences of care at a clinic in South Africa, and its associations with the respondents' sociodemographic characteristics. A survey was conducted in 2019 on a convenience sample of 179 respondents. Questions on experiences of care were based on a standardised set of questions by the Organization for Economic Co-operation and Development (OECD). Logistic regression was used to examine the effects of respondents' characteristics on their experiences. The proportion of respondents who reported that a nurse spent adequate time with them during consultation was significantly higher among literate respondents (92.3 vs. 79.5%). Those who reported past negative experiences were significantly more likely to report a positive experience in regard to perceiving adequate consulting time (odds ratio = 3.865, with a 95% confidence interval between 1.555 and 9.607), receiving easy-to-understand explanations (4.308; 1.665–11.145), being given the opportunity to ask questions (2.156; 1.013–4.589) and shared decision–making (3.822; 1.728–8.457). The results can spur comparisons with other clinics in a similar setting and inform key stakeholders on aspects of the care experience that need greater improvement within the national framework for quality and safety assurance and patient experience measurement.
Abstract
Serum amyloid P component (SAP), a member of the innate immune system, does not penetrate the brain in physiological conditions; however, SAP is a stabilizing component of the amyloid plaques in neurodegenerative diseases. We investigated the cerebrovascular transport of human SAP in animal experiments and in culture blood-brain barrier (BBB) models. After intravenous injection, no SAP could be detected by immunohistochemistry or ELISA in healthy rat brains. Salmonella typhimurium lipopolysaccharide injection increased BBB permeability for SAP and the number of cerebral vessels labeled with fluorescein isothiocyanate (FITC)-SAP in mice. Furthermore, when SAP was injected to the rat hippocampus, a time-dependent decrease in brain concentration was seen demonstrating a rapid SAP efflux transport in vivo. A temperature-dependent bidirectional transport of FITC-SAP was observed in rat brain endothelial monolayers. The permeability coefficient for FITC-SAP was significantly higher in abluminal to luminal (brain to blood) than in the opposite direction. The luminal release of FITC-SAP from loaded endothelial cells was also significantly higher than the abluminal one. Our data indicate the presence of BBB efflux transport mechanisms protecting the brain from SAP penetration. Damaged BBB integrity due to pathological insults may increase brain SAP concentration contributing to development of neurodegenerative diseases.
