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Tailor‐made microorganisms Microbial diversity provides unlimited resources for the development of novel industrial processes and products. Since the beginning of the 20th century microorganisms have been successfully applied for the large scale production of bio‐based products. In recent years, modern methods of strain development and Synthetic Biology have enabled biotech engineers to design even more sophisticated and tailor‐made microorganisms. These microbes serve industrial processes for the production of bulk chemicals, enzymes, polymers, biofuels as well as plant‐derived ingredients such as Artemisinin in an ecologically and economically sustainable and attractive fashion. In the future, production of advanced biofuels, microbial fuel cells, CO2 as feedstock and microbial cellulose are research topics as well as challenges of global importance. Continuous efforts in microbiology and biotechnology research will be pivotal for white biotechnology to gain more momentum in transforming the chemical industry towards a knowledge based bio‐economy.  相似文献   
13.
Summary Results of investigations on the occurrence of nerve fibres and endings in the synovial membrane of the knee and elbow joint in the cat are reported. The stratum synoviale contains only autonomic fibres, running in the adventitia of arteries.Free nerve endings are lacking in the stratum synoviale. Simple Pacinian corpuscles with an inner core are occasionally observed in the border zone between the stratum synoviale and fibrosum. The ultrastructure of these endorgans resembles that of Pacinian corpuscles in the hairless and hairy skin of the cat.  相似文献   
14.
Summary We recently described a nonradioactive method for in situ hybridization with 5-bromo-2-deoxyuridine (BrdU) labelled oligonucleotide probes. An antibody to BrdU and immunocytochemistry were used in order to detect the hybridization signal. We have now applied this method to semithin Epon sections, in order to hybridize consecutive sections through single cells with different probes and to stain them with antibodies to neuropeptides. It could be shown that Epon embedding preserves mRNA well. In the present study we used a BrdU labelled synthetic oligonucleotide probe complementary to a fragment of the vasopressin precursor and an antibody to Arg-vasopressin. Vasopressin mRNA was demonstrable in a fraction of the vasopressin immunoreactive neurons in the magnocellular nuclei. In addition some of the magnocellular neurons showed either hybridization or vasopressin immunostaining only, perhaps indicating different stages of synthetic and secretory activity. The method described seems to be a valuable tool for studying synthetic activity in peptidergic neurons on a single cell level. The method might also have potential for in situ hybridization on the electronmicroscopical level.  相似文献   
15.
Abstract

Opportunistic sightings and strandings of Caperea marginata (n=196) from the vicinity of Australia and New Zealand (1884 to early 2007) were used to relate geographic and temporal patterns to oceanographic and broad-scale climatic variability. Records were not uniformly distributed along the coast and more (69%) were from Australia than New Zealand. Seven coastal whale ‘hotspots’ were identified which accounted for 61% of records with locality data. Half of the hotspot records were from southeast (37) and northwest (20) Tasmania—others each had 9–15 events. Upwelling and/or high zooplankton abundance has been documented near all whale hotspots. Records of C. marginata occurred in all months, with 75% in spring and summer. Inter-annual variability showed broad agreement between increased whale records (usually in spring/summer) and strongly positive ‘Niño 3.4’ during 1980–1995 but not thereafter. Coastal upwelling and productivity increase during climatic phenomena such as El Niño and are likely to be quickly beneficial to plankton-feeding whales such as C. marginata.  相似文献   
16.
Effective management and conservation of migratory bird populations require knowledge and incorporation of their movement patterns and space use throughout the annual cycle. To investigate the little‐known migratory patterns of two grassland bird species, we deployed 180 light‐level geolocators on Grasshopper Sparrows (Ammodramus savannarum) and 29 Argos‐GPS tags on Eastern Meadowlarks (Sturnella magna) at Konza Prairie, Kansas, USA, and six US Department of Defense (DoD) installations distributed across the species' breeding ranges. We analyzed location data from 34 light‐level geolocators and five Argos‐GPS tags attached for 1 year to Grasshopper Sparrows and Eastern Meadowlarks, respectively. Grasshopper Sparrows were present on the breeding grounds from mid‐April through early October, substantially longer than previously estimated, and migrated on average ~2,500 km over ~30 days. Grasshopper Sparrows exhibited strong migratory connectivity only at a continental scale. The North American Great Lakes region likely serves as a migratory divide for Midwest and East Coast Grasshopper Sparrows; Midwest populations (Kansas, Wisconsin, and North Dakota; n = 13) largely wintered in Texas or Mexico, whereas East Coast populations (Maryland and Massachusetts, n = 20) wintered in the northern Caribbean or Florida. Our data from Eastern Meadowlarks provided evidence for a diversity of stationary and short‐ and long‐distance migration strategies. By providing the most extensive examination of the nonbreeding movement ecology for these two North American grassland bird species to date, we refine information gaps and provide key insight for their management and conservation.  相似文献   
17.
Juvenile myelomonocytic leukemia (JMML) is a unique myeloproliferative disorder of early childhood in which mutations in NRAS, KRAS, PTPN11, NF1 and CBL are frequently found. Using high-resolution oligo array-based comparative genomic hybridization (aCGH), 20 JMML samples were investigated for submicroscopic genomic copy number alterations. Besides known cytogenetic aberrations, ten samples displayed additional submicroscopic alterations. Interestingly, an almost identical gain of chromosome 8 was identified in two patients. Subsequently, fluorescence in situ hybridization indicated a constitutional partial trisomy 8 mosaic (cT8M) in both patients. A survey on 27 cT8M patients with reported malignancies showed a predominance of myeloid malignancies including JMML. Our results dramatically reduce the critical region on chromosome 8 to 8p11.21q11.21. To determine how constitutional partial trisomy 8 mosaicisms may contribute to leukemogenesis in different mutational subtypes of JMML and other myeloid malignancies, further investigations are required.  相似文献   
18.
Parasitic worms survive within their immunocompetent hosts by modulating their immune system and by inhibiting inflammatory responses directed against the parasites. This immunomodulation has a spill over effect and also inhibits inflammatory responses originating from other causes. For this reason, persons who are infected with certain species of worms show a lower rate of allergic diseases as compared to persons who are free of parasites. In the same line, studies in mouse models revealed that many inflammatory diseases can be treated by worm infections. This effect is among others owing to specific proteins that are released by the worms. Such secreted immunomodulators, shaped by co‐evolution between parasites and their hosts, could become lead compounds for the development of new therapies against allergic and inflammatory diseases.  相似文献   
19.
Dental anomalies in children with neuropediatric disorders are easy to diagnose and can be essential in the diagnosis of different entities. They are present in well-known disorders as Incontinentia pigmenti, but also in rare diseases as in Kohlschütter-Tönz syndrome or the recently described ataxia, delayed dentition and hypomyelination. Anomalies of dental shape, enamel and in this case also teeth color, dental number and eruption are all encountered. Knowledge of these abnormalities is important for both clinical geneticist and child neurologist.  相似文献   
20.
Because of their high prevalence, cases of coronary artery disease (CAD) and myocardial infarction (MI) are frequently found when asking for a patient’s family history. It is common knowledge that a positive familial history constitutes a risk factor for CAD in its own right, in addition to smoking, increased alcohol intake, diabetes, obesity, hypertension, and hyperlipidemia. Nevertheless, for correct risk assessment it is crucial to accurately distinguish between sporadic and true familial cases of CAD and MI. Familial disposition is present when at least one male first-grade relative under the age of 55 or one female first-grade relative under the age of 65 has/had been diagnosed with myocardial infarction or significant coronary artery disease. In the review presented here, we compile the relevant epidemiological and genetic studies that constitute the scientific basis of this risk assessment. Furthermore, a short overview of the state of the art of genetic CAD/MI research is given.  相似文献   
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