957 resultados para biological changes


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Bactrocera papayae Drew & Hancock, Bactrocera philippinensis Drew & Hancock, Bactrocera carambolae Drew & Hancock, and Bactrocera invadens Drew, Tsuruta & White are four horticultural pest tephritid fruit fly species that are highly similar, morphologically and genetically, to the destructive pest, the Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae). This similarity has rendered the discovery of reliable diagnostic characters problematic, which, in view of the economic importance of these taxa and the international trade implications, has resulted in ongoing difficulties for many areas of plant protection and food security. Consequently, a major international collaborative and integrated multidisciplinary research effort was initiated in 2009 to build upon existing literature with the specific aim of resolving biological species limits among B. papayae, B. philippinensis, B. carambolae, B. invadens and B. dorsalis to overcome constraints to pest management and international trade. Bactrocera philippinensis has recently been synonymized with B. papayae as a result of this initiative and this review corroborates that finding; however, the other names remain in use. While consistent characters have been found to reliably distinguish B. carambolae from B. dorsalis, B. invadens and B. papayae, no such characters have been found to differentiate the latter three putative species. We conclude that B. carambolae is a valid species and that the remaining taxa, B. dorsalis, B. invadens and B. papayae, represent the same species. Thus, we consider B. dorsalis (Hendel) as the senior synonym of B. papayae Drew and Hancock syn.n. and B. invadens Drew, Tsuruta & White syn.n. A redescription of B. dorsalis is provided. Given the agricultural importance of B. dorsalis, this taxonomic decision will have significant global plant biosecurity implications, affecting pest management, quarantine, international trade, postharvest treatment and basic research. Throughout the paper, we emphasize the value of independent and multidisciplinary tools in delimiting species, particularly in complicated cases involving morphologically cryptic taxa.

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This thesis focuses on the role of a bone cell, osteocytes in the progression of osteoarthritis. The biological relevance of this study has opened doors to new possibilities of understanding the pathogenesis of osteoarthritis.

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Erythropoietin (EPO), a glycoprotein hormone of ∼34 kDa, is an important hematopoietic growth factor, mainly produced in the kidney and controls the number of red blood cells circulating in the blood stream. Sensitive and rapid recombinant human EPO (rHuEPO) detection tools that improve on the current laborious EPO detection techniques are in high demand for both clinical and sports industry. A sensitive aptamer-functionalized biosensor (aptasensor) has been developed by controlled growth of gold nanostructures (AuNS) over a gold substrate (pAu/AuNS). The aptasensor selectively binds to rHuEPO and, therefore, was used to extract and detect the drug from horse plasma by surface enhanced Raman spectroscopy (SERS). Due to the nanogap separation between the nanostructures, the high population and distribution of hot spots on the pAu/AuNS substrate surface, strong signal enhancement was acquired. By using wide area illumination (WAI) setting for the Raman detection, a low RSD of 4.92% over 150 SERS measurements was achieved. The significant reproducibility of the new biosensor addresses the serious problem of SERS signal inconsistency that hampers the use of the technique in the field. The WAI setting is compatible with handheld Raman devices. Therefore, the new aptasensor can be used for the selective extraction of rHuEPO from biological fluids and subsequently screened with handheld Raman spectrometer for SERS based in-field protein detection.

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Dorsiflexion (DF) of the foot plays an essential role in both controlling balance and human gait. Electromyography and Sonomyography can provide information on several aspects of muscle function. The aim was to describe a new method for real-time monitoring of muscular activity, as measured using EMG, muscular architecture, as measured using SMG, force, as measured using dynamometry, and kinematic parameters, as measured using IS during isometric and isotonic contractions of the foot DF. The present methodology may be clinically relevant because it involves a reproducible procedure which allows the function and structure of the foot DF to be monitored.

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Accurate radiocarbon dating of marine samples requires knowledge of the marine radiocarbon reservoir effect. This effect for a particular site/region is generally assumed constant through time when calibrating marine 14C ages. However, recent studies have shown large temporal variations of several hundred to a couple of thousand years in this effect for a number of regions during the late Quaternary and Holocene. Here we report marine radiocarbon reservoir correction (ΔRΔR) for Heron Reef and Moreton Bay in southwestern (SW) Pacific for the last 8 ka derived from 14C analysis of 230Th-dated corals. Most of our ΔRΔR for the last ∼5.4 ka agree well with their modern value, but large ΔRΔR variability of ∼410 yr (from trough to peak) with possible decadal/centennial fluctuations is evident for the period ∼5.4–8 ka. The latter time interval also has significant variations with similar features in previously published ΔRΔR values for other sites in the Pacific, including southern Peru–northern Chile in southeastern (SE) Pacific, the South China Sea, Vanuatu and Papua New Guinea, with the largest magnitude of ∼920 yr from SE Pacific. The mechanisms for these large ΔRΔR variations across the Pacific during the mid-Holocene are complex processes involving (1) changes in the quantity and 14C content of upwelled waters in tropical east Pacific (TEP) (frequency and intensity of ocean upwelling in the TEP, and contribution of Subantarctic Mode Water to the upwelled waters, which is influenced by the intensity and position of southern westerly winds), and (2) variations in ocean circulation associated with climate change (La Niña/El Niño conditions, intensity of easterly trade winds, positions of the Intertropical Convergence Zone and the South Pacific Convergence Zone), which control the spreading of the older upwelled surface waters in the TEP to the western sites. Our results imply the need for employing temporal changes in ΔRΔR values, instead of constant (modern) values, for age calibration of Holocene marine samples not only for the SW Pacific sites but also for other tropical and subtropical sites in the Pacific.

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The crystal structures of complexes of Mycobacterium tuberculosis pantothenate kinase with the following ligands have been determined: (i) citrate; (ii) the nonhydrolysable ATP analogue AMPPCP and pantothenate (the initiation complex); (iii) ADP and phosphopantothenate resulting from phosphorylation of pantothenate by ATP in the crystal (the end complex); (iv) ATP and ADP, each with half occupancy, resulting from a quick soak of crystals in ATP (the intermediate complex); (v) CoA; (vi) ADP prepared by soaking and cocrystallization, which turned out to have identical structures, and (vii) ADP and pantothenate. Solution studies on CoA binding and catalytic activity have also been carried out. Unlike in the case of the homologous Escherichia coli enzyme, AMPPCP and ADP occupy different, though overlapping, locations in the respective complexes; the same is true of pantothenate in the initiation complex and phosphopantothenate in the end complex. The binding site of MtPanK is substantially preformed, while that of EcPanK exhibits considerabl plasticity. The difference in the behaviour of the E. coli and M. tuberculosis enzymes could be explained in terms of changes in local structure resulting from substitutions. It is unusual for two homologous enzymes to exhibit such striking differences in action. Therefore, the results have to be treated with caution. However, the changes in the locations of ligands exhibited by M. tuberculosis pantothenate kinase are remarkable and novel.

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Nephrin is a transmembrane protein belonging to the immunoglobulin superfamily and is expressed primarily in the podocytes, which are highly differentiated epithelial cells needed for primary urine formation in the kidney. Mutations leading to nephrin loss abrogate podocyte morphology, and result in massive protein loss into urine and consequent early death in humans carrying specific mutations in this gene. The disease phenotype is closely replicated in respective mouse models. The purpose of this thesis was to generate novel inducible mouse-lines, which allow targeted gene deletion in a time and tissue-specific manner. A proof of principle model for succesful gene therapy for this disease was generated, which allowed podocyte specific transgene replacement to rescue gene deficient mice from perinatal lethality. Furthermore, the phenotypic consequences of nephrin restoration in the kidney and nephrin deficiency in the testis, brain and pancreas in rescued mice were investigated. A novel podocyte-specific construct was achieved by using standard cloning techniques to provide an inducible tool for in vitro and in vivo gene targeting. Using modified constructs and microinjection procedures two novel transgenic mouse-lines were generated. First, a mouse-line with doxycycline inducible expression of Cre recombinase that allows podocyte-specific gene deletion was generated. Second, a mouse-line with doxycycline inducible expression of rat nephrin, which allows podocyte-specific nephrin over-expression was made. Furthermore, it was possible to rescue nephrin deficient mice from perinatal lethality by cross-breeding them with a mouse-line with inducible rat nephrin expression that restored the missing endogenous nephrin only in the kidney after doxycycline treatment. The rescued mice were smaller, infertile, showed genital malformations and developed distinct histological abnormalities in the kidney with an altered molecular composition of the podocytes. Histological changes were also found in the testis, cerebellum and pancreas. The expression of another molecule with limited tissue expression, densin, was localized to the plasma membranes of Sertoli cells in the testis by immunofluorescence staining. Densin may be an essential adherens junction protein between Sertoli cells and developing germ cells and these junctions share similar protein assembly with kidney podocytes. This single, binary conditional construct serves as a cost- and time-efficient tool to increase the understanding of podocyte-specific key proteins in health and disease. The results verified a tightly controlled inducible podocyte-specific transgene expression in vitro and in vivo as expected. These novel mouse-lines with doxycycline inducible Cre recombinase and with rat nephrin expression will be useful for conditional gene targeting of essential podocyte proteins and to study in detail their functions in the adult mice. This is important for future diagnostic and pharmacologic development platforms.

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The purpose of the present study was to increase understanding of the interaction of rural people and, specifically, women with the environment in a dry area in Sudan. The study that included both nomadic pastoralists and farmers aimed at answering two main research questions, namely: What kinds of roles have the local people, and the women in particular, had in land degradation in the study area and what kinds of issues would a gender-sensitive, forestry-related environmental rehabilitation intervention need to consider there? The study adopted the definition of land degradation as proposed by the United Nations Convention to Combat Desertification (UNCCD), which describes land degradation as reduction or loss the biological or economic productivity and complexity of land in arid, semi-arid and dry sub-humid areas. The Convention perceives desertification as land degradation. The dry study area in Sudan, South of the Sahara, has been the subject of land degradation or desertification discussions since the 1970s, and other studies have been also conducted to assess the degradation in the area. Nevertheless, the exact occurrence, scale and local significance of land degradation in the area is still unclear. This study explored how the rural population whose livelihood depended on the area, perceived environmental changes occurring there and compared their conceptions with other sources of information of the area such as research reports. The main fieldwork methods included interviews with open-ended questions and observation of people and the environment. The theoretical framework conceptualised the rural population as land users whose choices of environmental activities are affected by multiple factors in the social and biophysical contexts in which they live. It was emphasised that these factors have their own specific characteristics in different contexts, simultaneously recognising that there are also factors that generally affect environmental practices in various areas such as the land users' environmental literacy (conceptions of the environment), gender and livelihood needs. The people studied described that environmental changes, such as reduced vegetation cover and cropland production, had complicated the maintenance of their livelihoods in the study area. Some degraded sites were also identified through observations during the fieldwork. Whether a large-scale reduction of cropland productivity had occurred in the farmers' croplands remained, however, unclear. The study found that the environmental impact of the rural women's activities varied and was normally limited. The women's most significant environmental impact resulted from their cutting of trees, which was likely to contribute, at least in some places, to land degradation, affecting the environment together with climate and livestock. However, when a wider perspective is taken, it becomes questionable whether the women have really played roles in land degradation, since gender, poverty and the need to maintain livelihood had caused them to conduct environmentally harmful activities. The women have had, however, no power to change the causes of their activities. The findings further suggested that an inadequate availability of food was the most critical problem in the study area. Therefore, an environmental programme in the area was suggested to include technical measures to increase the productivity of croplands, opportunities for income generation and readiness to co-operate with other programmes to improve the local people's abilities to maintain their livelihoods. In order to protect the environment and alleviate the women's work burden, the introduction of fuel-saving stoves was also suggested. Furthermore, it was suggested that increased planting of trees on homesteads would be supported by an easy availability of tree seedlings. Planting trees on common property land was, however, perceived as extremely demanding in the study area, due to scarcity of such land. In addition, it became apparent that the local land users, and women in particular, needed to allocate their labour to maintain the immediate livelihood of their families and were not motivated to allocate their labour solely for environmental rehabilitation. Nonetheless, from the point of view of the existing social structures, women's active participation in a community-based environmental programme would be rather natural, particularly among the farmer women who had already formed a women's group and participated in communal decision making. Forming of a women group or groups was suggested to further support both the farmer women's and pastoral women's active participation within an environmental programme and their general empowerment. An Environmental programme would need to acknowledge that improving rural people's well-being and maintaining their livelihood in the study area requires development and co-operation with various sectors in Sudan.

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The present study examined whether a specific property of cell microstructures may be useful as a biomarker of aging. Specifically, the association between age and changes of cellular structures reflected in electrophoretic mobility of cell nuclei index (EMN index) values across the adult lifespan was examined. This report considers findings from cross sections of females (n = 1273) aged 18–98 years, and males (n = 506) aged 19–93 years. A Biotest apparatus was used to perform intracellular microelectrophoresis on buccal epithelial cells collected from each individual. EMN index was calculated on the basis of the number of epithelial cells with mobile nuclei in reference to the cells with immobile nuclei per 100 cells. Regression analyses indicated a significant negative association between EMN index value and age for men (r = −0.71, p < 0.001) and women (r = −0.60, p < 0.001); demonstrating a key requirement that must be met by a biomarker of aging. The strength of association observed between EMN index and age for both men and women was encouraging and supports the potential use of EMN index for determining a biological age of an individual (or a group). In this study, a new attempt of complex explanation of cellular mechanisms contributing to age related changes of the EMN index was made. In this study, a new attempt of complex explanation of cellular mechanisms contributing to age related changes of the EMN index was made. EMN index has demonstrated potential to meet criteria proposed for biomarkers of aging and further investigations are necessary.

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Vachellia nilotica ssp. indica (hereafter, V. n. indica) is an important tree weed in Australia. Its dense populations induce undesirable changes in the vast areas of northern Australia. Because chemical and mechanical management options appear unviable for various reasons, biological management of this tree is considered a better option. Among the many trialled arthropods in Australian context, Anomalococcus indicus, a lecanodiaspid native to India, has been identified as a potent-candidate, since in India, its native terrain, it is the most widespread and occurs throughout the year. Severe infestations of A. indicus cause defoliation, wilting and death of branches, and occasionally the tree. Populations of A. indicus have been brought into Australia and are being tested for its host specificity under quarantine conditions. This article reports the physiological damage and stress it inflicts in the shoots of V. n. indica. Younger-nymphal instars of A. indicus feed on cortical-parenchyma cells of young stems, whereas the older instars and adults feed from the phloem of old stems. Two conspicuous responses of V. n. indica arising in response to the feeding action of A. indicus are changes in the cell-wall dynamics and irregular cell divisions. The feeding action of A. indicus elicits a sequence of reactions in the stem tissues of V. n. indica such as differentiation of thick-walled elements in the outer cortical parenchyma, differential thickening of cells with supernumerary layers of either suberin or lignin, proliferations of parenchyma and phloem, wall thickening and obliteration of inner lumen of phloem cells, and the sieve plates plugged with callosic deposits. The responses are the culminations of interaction between the virulence factor (one or more of the salivary proteins?) from A. indicus and the resistance factor in V. n. indica. We have analysed structural changes in the context of their functions, by comparing the feeding action of A. indicus with that of other hemipteroids. From the level of stress it induces, this study confirms that A. indicus has the potential to be an effective biological management of V. n. indica in Australia. © 2014 © 2014 Taylor & Francis and Aboricultural Association.

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Assessing storage impacts on manure properties is relevant to research associated with nutrient-use efficiency and greenhouse gas (GHG) emissions. We examined the impact of cold storage on physicochemical properties, biochemical methane-emitting potential (BMP) and the composition of microbial communities of beef feedlot manure and poultry broiler litter. Manures were analysed within 2 days of collection and after 2 and 8 weeks in refrigerated (4 °C) or frozen (–20 °C) storage. Compared with fresh manure, stored manures had statistically significant (p < 0.05) but comparatively minor (<10%) changes in electrical conductivity, chloride and ammonium concentrations. Refrigeration and freezing did not significantly affect (p > 0.05) BMP in both manure types. We did not detect ammonium- or nitrite-oxidising bacterial taxa (AOB, NOB) using fluorescence in situ hybridisation (FISH). Importantly, the viability of microbes was unchanged by storage. We conclude that storage at –20 °C or 4 °C adequately preserves the investigated traits of the studied manures for research aimed at improving nutrient cycling and reducing GHG emissions.

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Postglacial climate changes and vegetation responses were studied using a combination of biological and physical indicators preserved in lake sediments. Low-frequency trends, high-frequency events and rapid shifts in temperature and moisture balance were probed using pollen-based quantitative temperature reconstructions and oxygen-isotopes from authigenic carbonate and aquatic cellulose, respectively. Pollen and plant macrofossils were employed to shed light on the presence and response rates of plant populations in response to climate changes, particularly focusing on common boreal and temperate tree species. Additional geochemical and isotopic tracers facilitated the interpretation of pollen- and oxygen-isotope data. The results show that the common boreal trees were present in the Baltic region (~55°N) during the Lateglacial, which contrasts with the traditional view of species refuge locations in the south-European peninsulas during the glacial/interglacial cycles. The findings of this work are in agreement with recent paleoecological and genetic evidence suggesting that scattered populations of tree species persisted at higher latitudes, and that these taxa were likely limited to boreal trees. Moreover, the results demonstrate that stepwise changes in plant communities took place in concert with major climate fluctuations of the glacial/interglacial transition. Postglacial climate trends in northern Europe were characterized by rise, maxima and fall in temperatures and related changes in moisture balance. Following the deglaciation of the Northern Hemisphere and the early Holocene reorganization of the ice-ocean-atmosphere system, the long-term temperature trends followed gradually decreasing summer insolation. The early Holocene (~11,700-8000 cal yr BP) was overall cool, moist and oceanic, although the earliest Holocene effective humidity may have been low particularly in the eastern part of northern Europe. The gradual warming trend was interrupted by a cold event ~8200 cal yr BP. The maximum temperatures, ~1.5-3.0°C above modern values, were attained ~8000-4000 cal yr BP. This mid-Holocene peak warmth was coupled with low lake levels, low effective humidity and summertime drought. The late Holocene (~4000 cal yr BP-present) was characterized by gradually decreasing temperatures, higher lake levels and higher effective humidity. Moreover, the gradual trends of the late Holocene were probably superimposed by higher-frequency variability. The spatial variability of the Holocene temperature and moisture balance patterns were tentatively attributed to the differing heat capacities of continents and oceans, changes in atmospheric circulation modes and position of sites and subregions with respect to large water bodies and topographic barriers. The combination of physical and biological proxy archives is a pivotal aspect of this work, because non-climatic factors, such as postglacial migration, disturbances and competitive interactions, can influence reshuffling of vegetation and hence, pollen-based climate reconstructions. The oxygen-isotope records and other physical proxies presented in this work manifest that postglacial climate changes were the main driver of the establishment and expansion of temperate and boreal tree populations, and hence, large-scale and long-term vegetation patterns were in dynamic equilibrium with climate. A notable exception to this pattern may be the postglacial invasion of Norway spruce and the related suppression of mid-Holocene temperate forest. This salient step in north-European vegetation history, the development of the modern boreal ecosystem, cannot be unambiguously explained by current evidence of postglacial climate changes. The results of this work highlight that plant populations, including long-lived trees, may be able to respond strikingly rapidly to changes in climate. Moreover, interannual and seasonal variation and extreme events can exert an important influence on vegetation reshuffling. Importantly, the studies imply that the presence of diffuse refuge populations or local stands among the prevailing vegetation may have provided the means for extraordinarily rapid vegetation responses. Hence, if scattered populations are not provided and tree populations are to migrate long distances, their capacity to keep up with predicted rates of future climate change may be lower than previously thought.

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In northern latitudes, temperature is the key factor driving the temporal scales of biological activity, namely the length of the growing season and the seasonal efficiency of photosynthesis. The formation of atmospheric concentrations of biogenic volatile organic compounds (BVOCs) are linked to the intensity of biological activity. However, interdisciplinary knowledge of the role of temperature in the biological processes related to the annual cycle and photosynthesis and atmospheric chemistry is not fully understood. The aim of this study was to improve understanding of the role of temperature in these three interlinked areas: 1) onset of growing season, 2) photosynthetic efficiency and 3) BVOC air concentrations in a boreal forest. The results present a cross-section of the role of temperature on different spatial (southern northern boreal), structural (tree forest stand - forest) and temporal (day-season- year) scales. The fundamental status of the Thermal Time model in predicting the onset of spring recovery was confirmed. However, it was recommended that sequential models would be more appropriate tools when the onset of the growing season is estimated under a warmer climate. A similar type of relationship between photosynthetic efficiency and temperature history was found in both southern and northern boreal forest stands. This result draws attention to the critical question of the seasonal efficiency of coniferous species to emit organic compounds under a warmer climate. New knowledge about the temperature dependence of the concentrations of biogenic volatile organic compounds in a boreal forest stand was obtained. The seasonal progress and the inter-correlation of BVOC concentrations in ambient air indicated a link to biological activity. Temperature was found to be the main driving factor for the concentrations. However, in addition to temperature, other factors may play a significant role here, especially when the peak concentrations are studied. There is strong evidence that the spring recovery and phenological events of many plant species have already advanced in Europe. This study does not fully support this observation. In a boreal forest, changes in the annual cycle, especially the temperature requirement in winter, would have an impact on the atmospheric BVOC composition. According to this study, more joint phenological and BVOC field observations and laboratory experiments are still needed to improve these scenarios.

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Staphylococcus aureus is one of the most important bacteria that cause disease in humans, and methicillin-resistant S. aureus (MRSA) has become the most commonly identified antibiotic-resistant pathogen in many parts of the world. MRSA rates have been stable for many years in the Nordic countries and the Netherlands with a low MRSA prevalence in Europe, but in the recent decades, MRSA rates have increased in those low-prevalence countries as well. MRSA has been established as a major hospital pathogen, but has also been found increasingly in long-term facilities (LTF) and in communities of persons with no connections to the health-care setting. In Finland, the annual number of MRSA isolates reported to the National Infectious Disease Register (NIDR) has constantly increased, especially outside the Helsinki metropolitan area. Molecular typing has revealed numerous outbreak strains of MRSA, some of which have previously been associated with community acquisition. In this work, data on MRSA cases notified to the NIDR and on MRSA strain types identified with pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and staphylococcal cassette chromosome mec (SCCmec) typing at the National Reference Laboratory (NRL) in Finland from 1997 to 2004 were analyzed. An increasing trend in MRSA incidence in Finland from 1997 to 2004 was shown. In addition, non-multi-drug resistant (NMDR) MRSA isolates, especially those resistant only to methicillin/oxacillin, showed an emerging trend. The predominant MRSA strains changed over time and place, but two internationally spread epidemic strains of MRSA, FIN-16 and FIN-21, were related to the increase detected most recently. Those strains were also one cause of the strikingly increasing invasive MRSA findings. The rise of MRSA strains with SCCmec types IV or V, possible community-acquired MRSA was also detected. With questionnaires, the diagnostic methods used for MRSA identification in Finnish microbiology laboratories and the number of MRSA screening specimens studied were reviewed. Surveys, which focused on the MRSA situation in long-term facilities in 2001 and on the background information of MRSA-positive persons in 2001-2003, were also carried out. The rates of MRSA and screening practices varied widely across geographic regions. Part of the NMDR MRSA strains could remain undetected in some laboratories because of insufficient diagnostic techniques used. The increasing proportion of elderly population carrying MRSA suggests that MRSA is an emerging problem in Finnish long-term facilities. Among the patients, 50% of the specimens were taken on a clinical basis, 43% on a screening basis after exposure to MRSA, 3% on a screening basis because of hospital contact abroad, and 4% for other reasons. In response to an outbreak of MRSA possessing a new genotype that occurred in a health care ward and in an associated nursing home of a small municipality in Northern Finland in autumn 2003, a point-prevalence survey was performed six months later. In the same study, the molecular epidemiology of MRSA and methicillin-sensitive S. aureus (MSSA) strains were also assessed, the results to the national strain collection compared, and the difficulties of MRSA screening with low-level oxacillin-resistant isolates encountered. The original MRSA outbreak in LTF, which consisted of isolates possessing a nationally new PFGE profile (FIN-22) and internationally rare MLST type (ST-27), was confined. Another previously unrecognized MRSA strain was found with additional screening, possibly indicating that current routine MRSA screening methods may be insufficiently sensitive for strains possessing low-level oxacillin resistance. Most of the MSSA strains found were genotypically related to the epidemic MRSA strains, but only a few of them had received the SCCmec element, and all those strains possessed the new SCCmec type V. In the second largest nursing home in Finland, the colonization of S. aureus and MRSA, and the role of screening sites along with broth enrichment culture on the sensitivity to detect S. aureus were studied. Combining the use of enrichment broth and perineal swabbing, in addition to nostrils and skin lesions swabbing, may be an alternative for throat swabs in the nursing home setting, especially when residents are uncooperative. Finally, in order to evaluate adequate phenotypic and genotypic methods needed for reliable laboratory diagnostics of MRSA, oxacillin disk diffusion and MIC tests to the cefoxitin disk diffusion method at both +35°C and +30°C, both with or without an addition of sodium chloride (NaCl) to the Müller Hinton test medium, and in-house PCR to two commercial molecular methods (the GenoType® MRSA test and the EVIGENETM MRSA Detection test) with different bacterial species in addition to S. aureus were compared. The cefoxitin disk diffusion method was superior to that of oxacillin disk diffusion and to the MIC tests in predicting mecA-mediated resistance in S. aureus when incubating at +35°C with or without the addition of NaCl to the test medium. Both the Geno Type® MRSA and EVIGENETM MRSA Detection tests are usable, accurate, cost-effective, and sufficiently fast methods for rapid MRSA confirmation from a pure culture.