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1.
In the late 1960s Van Rensselaer Potter, a biochemist and cancer researcher, thought that our survival was threatened by the
domination of military policy makers and producers of material goods ignorant of biology. He called for a new field of Bioethics—“a
science of survival.” Bioethics did develop, but with a narrower focus on medical ethics. Recently there have been attempts
to broaden that focus to bring biomedical ethics together with environmental ethics. Though the two have many differences—in
habits of thought, scope of concern, and value commitments—in this paper we argue that they often share common cause and we
identify common ground through an examination of two case studies, one addressing drug development, the other food production. 相似文献
2.
João R. M. Almeida Magnus Bertilsson Marie F. Gorwa-Grauslund Steven Gorsich Gunnar Lidén 《Applied microbiology and biotechnology》2009,82(4):625-638
There is a growing awareness that lignocellulose will be a major raw material for production of both fuel and chemicals in
the coming decades—most likely through various fermentation routes. Considerable attention has been given to the problem of
finding efficient means of separating the major constituents in lignocellulose (i.e., lignin, hemicellulose, and cellulose)
and to efficiently hydrolyze the carbohydrate parts into sugars. In these processes, by-products will inevitably form to some
extent, and these will have to be dealt with in the ensuing microbial processes. One group of compounds in this category is
the furaldehydes. 2-Furaldehyde (furfural) and substituted 2-furaldehydes—most importantly 5-hydroxymethyl-2-furaldehyde—are
the dominant inhibitory compounds found in lignocellulosic hydrolyzates. The furaldehydes are known to have biological effects
and act as inhibitors in fermentation processes. The effects of these compounds will therefore have to be considered in the
design of biotechnological processes using lignocellulose. In this short review, we take a look at known metabolic effects,
as well as strategies to overcome problems in biotechnological applications caused by furaldehydes. 相似文献
3.
O. A. Koksharova 《Microbiology》2010,79(6):721-734
The review discusses the advances and problems in biotechnology and ecology of cyanobacteria and considers the possibilities
of molecular genetic and microbiological techniques in this field. Due to the ease of cultivation, high growth rate, availability
of synchronous cultures, and existence of numerous molecular genetic and microbiological techniques for various cyanobacterial
strains, cyanobacteria—prokaryotic organisms that are ancient relatives of the chloroplasts—are model organisms in the studies
of photosynthesis, dinitrogen fixation, cell division, hydrogen production, and in a number of other areas of basic and applied
science. These techniques make possible deeper understanding of the role of cyanobacteria in various ecosystems and utilization
of their potential in numerous applied projects, including production of molecular hydrogen, phycobiliproteins, and cyanophycin;
formation of nanoparticles; removal of heavy metals from the environment; substrate biodegradation; manufacture of products
for medicine and food industry; and solution of the problem of cyanobacterial toxins in freshwater and marine environments. 相似文献
4.
Bistra Atanassova 《Acta Physiologiae Plantarum》2000,22(3):221-225
Advantages and disadvantages in using functional male sterility (positional sterile — ps, positional sterile 2 — ps 2, and excerted stigma — ex) in tomato hybrid seed production and attempts to elaborate systems for their more efficacious use in breeding were discussed
in this review. It was concluded that the application of one of these types of sterility, (ps 2) in practice, although in a limited number of countries, showed the functional male sterility in tomato was a potential not
to be underestimated in developing approaches that aimed at reducting the time and cost associated with hybrid seed production. 相似文献
5.
6.
In this short review, we will first discuss localized cytoplasmic calcium signals in pancreatic acinar cells. In the second
part of the review, we will describe recently discovered polarized calcium efflux and calcium propagation through the lumen
of the endoplasmic reticulum — ER (a phenomenon we have termed “calcium tunnelling”). Finally, we will present a hypothesis
concerning the roles that these mechanisms could play in transcellular calcium flux. 相似文献
7.
Amir Neori 《Journal of applied phycology》2011,23(1):143-149
Freshwater fish culture is generally considered the largest sector in world aquaculture. Several of the leading species consume
“green water” plankton. This plankton—mostly microalgae (phytoplankton) and also bacteria, protozoa and zooplankton—grows
in man-made fertilized water impoundments. The quantity of “green water” microalgae consumed by fish and shrimp is estimated
here at a quarter billion ton fresh weight a year, about three and a half times as much as the entire recognized aquaculture.
This estimate is based on the quantities of the microalgae consumed and the efficiencies of their use for growth by the main
species in aquaculture. The cost of producing “green water” microalgae by the aquaculturists—mostly in SE Asia—is low. The
populations in “green water” are biologically managed by the cultured fish themselves. The fish with their different feeding
habits help “manage” the composition of the plankton and the overall water quality as they grow. The aquaculturists further
manage “green water” through simple means, including water exchange and fertilization. Cost is remunerated partially by the
income from sales of the fish and partially by bio mitigation services that “green water” polyculture ponds provide the aquaculturists
in treating farm and household waste. A comprehension of the scale and importance of the microalgae sector to world aquaculture
should lead to more research to improve understanding of algal population dynamics, growth factors, and efficiency of food
chains. The consequent improved control of the plankton’s interaction with fish and shrimp production in “green water” will
undoubtedly contribute much to the expansion in production of seafood. 相似文献
8.
N. A. Pakharukova L. Kh. Pastushkova S. A. Moshkovskii I. M. Larina 《Biochemistry (Moscow) Supplemental Series B: Biomedical Chemistry》2011,5(3):203-212
The aim of this review is to analyze results of studies on characteristics of protein variability and diversity of posttranslational
modifications of proteins in healthy humans. Numerous studies have demonstrated that a proteomic profile is characterized
by significant intra- and inter-individual variability, and quite often natural (“normal”) variability of some proteins can
be comparable to changes observed in pathological processes. Results obtained by our research group have demonstrated high
intra-individual variability of serum low-molecular subproteome of healthy volunteers, certified by a special medial committee
(the coefficient of variation (CV) of 42.6%). The proteins characterized by high variability under normal conditions (e.g.
haptoglobin — 0–40 mg/ml; lysozyme — 0.01–0.1 mg/ml; C-reactive protein — 0.01–0.3 mg/ml) cannot be considered as potential
biomarkers of diseases. On the contrary, proteins and peptides characterized by insignificant dispersion in healthy population
(such as albumin ( CV = 9%); transferrin-(CV = 14%); C3c complement (CV = 17%), α-1 acid glycoprotein (CV = 21%), α-2-macroglobulin
(CV = 20%); transthyretin fragment (CV = 28.3%) and α2-HS-glycoprotein βchain (CV = 29.7%)) can provide valuable information
about the state of health. Thus, studies of plasticity in the proteomic profiles of healthy humans will help to correct reference
intervals used in clinical proteomics. 相似文献
9.
A gluten-free (GF) diet is recognised as being the only accepted treatment for celiac disease—a permanent autoimmune enteropathy
triggered by the ingestion of gluten-containing cereals. The bakery products available in today’s gluten-free market are characterised
by lower palatability than their conventional counterparts and may lead to nutritional deficiencies of vitamins, minerals
and fibre. Thus, the production of high-quality gluten-free products has become a very important socioeconomical issue. Microbial
fermentation by means of lactic acid bacteria and yeast is one of the most ecological/economical methods of producing and
preserving food. In this review, the role of a fermentation process for improving the quality of GF products and for developing
a new concept of GF products with nutraceutical and health-promoting characteristics will be examined. 相似文献
10.
Formation of volatile sulfur compounds and metabolism of methionine and other sulfur compounds in fermented food 总被引:3,自引:0,他引:3
The formation of volatile sulfur compounds (VSC) in fermented food is a subject of interest. Such compounds are essential
for the aroma of many food products like cheeses or fermented beverages, in which they can play an attractive or a repulsive
role, depending on their identity and their concentration. VSC essentially arise from common sulfur-bearing precursors, methionine
being the most commonly found. In the first section of this paper, the main VSC found in cheese, wine, and beer are reviewed.
It is shown that a wide variety of VSC has been evidenced in these food products. Because of their low odor threshold and
flavor notes, these compounds impart essential sensorial properties to the final product. In the second section of this review,
the main (bio)chemical pathways leading to VSC synthesis are presented. Attention is focused on the microbial/enzymatic phenomena—which
initiate sulfur bearing precursors degradation—leading to VSC production. Although chemical reactions could also play an important
role in this process, this aspect is not fully developed in our review. The main catabolic pathways leading to VSC from the
precursor methionine are presented. 相似文献
11.
Llorenç Milà i Canals Xavier Domènèch Joan Rieradevall Rita Puig Pere Fullana 《The International Journal of Life Cycle Assessment》2002,7(1):39-46
Life Cycle Assessment (LCA) has been used to detect the environmental ‘hot spots’ in the chrome-tanned bovine leather industry. We have studied those stages in the life cycle of leather, which occur ‘from cradle to gate’. The production chain studied starts with the agricultural products (fertiliser and pesticide production is also included) needed for cattle raising, it is followed by the slaughterhouse, and ends at the tanning industry gate. Main chemicals and waste flows in and out of this chain have also been included in the analysis. One of the main conclusions is that the tannery is an important stage in most of the impact categories, mainly due to the landfilling of the tannery wastes. Agriculture and — to a lesser extent — cattle raising also play a very important role in most of the impact categories; the former, due to the related energy consumption and use of fertilisers, and the latter due to the emissions associated with animal care. The Autonomous Government of Catalonia is using the results of this study to establish the environmental criteria that a leather product must fulfil in order to attain the Catalan eco-label. 相似文献
12.
Biotechnological production of itaconic acid and its biosynthesis in <Emphasis Type="Italic">Aspergillus terreus</Emphasis> 总被引:1,自引:0,他引:1
Mitsuyasu Okabe Dwiarti Lies Shin Kanamasa Enoch Y. Park 《Applied microbiology and biotechnology》2009,84(4):597-606
More than 80,000 tons of itaconic acid (IA) is produced worldwide each year and is sold at a price of around US$ 2/kg. The
IA production yield from sugar is higher than 80 g/l. The widespread use of IA in synthetic resins, synthetic fibers, plastics,
rubbers, surfactants, and oil additives has resulted in an increased demand for this product. However, at present, the IA
production capacity exceeds the demand because this product has a restricted range of applications. Studies have been actively
conducted in different biomedical fields—dental, ophthalmic, and drug delivery—to extend the range of applications of IA.
Recently, many researchers have attempted to replace the carbon source used for microbial production of IA with cheaper alternative
substrates. However, there is still a need for new biotechnology innovations that would help to reduce the production costs,
such as innovative process development and strain improvement to allow the use of a low-quality carbon source. In this short
review, we discuss the following aspects of IA production: strain improvement, process development, identification of the
key enzyme cis-aconitic acid decarboxylase (CAD) in the IA metabolic pathway, metabolic importance of CAD, and new applications of IA. 相似文献
13.
Bell A 《Biological cybernetics》2007,96(4):421-438
Frequency analysis by the mammalian cochlea is traditionally thought to occur via a hydrodynamically coupled ‘travelling wave’
along the basilar membrane. A persistent difficulty with this picture is how sharp tuning can emerge. This paper proposes,
and models, a supplementary or alternative mechanism: it supposes that the cochlea analyses sound by setting up standing waves
between parallel rows of outer hair cells. In this scheme, multiple cells mutually interact through positive feedback of wave-borne
energy. Analytical modelling and numerical evaluation presented here demonstrate that this can provide narrow-band frequency
analysis. Graded cochlear tuning will then rely on the distance between rows becoming greater as distance from the base increases
(as exhibited by the actual cochlea) and on the wave’s phase velocity becoming slower. In effect, tuning is now a case of
varying the feedback delay between the rows, and a prime candidate for a wave exhibiting suitably graded phase velocity—a
short-wavelength ‘squirting wave’—is identified and used in the modelling. In this way, resonance between rows could supply
both amplification and high Q, characteristics underlying the ‘cochlear amplifier’—the device whose action has long been evident to auditory science but
whose anatomical basis and mode of operation are still obscure. 相似文献
14.
Amar J. S. Klar 《Journal of biosciences》2010,35(1):11-15
“The two big problems — the nature of development and the nature of the mind — are being subdued. I don’t know whether there
will be beautiful, general theories to come out of this — something really nice like Watson and Crick’s double helix — or
whether there will be an accumulation of more and more details. I’ll confess to a secret hope for the former” (Crow 2000). 相似文献
15.
A great number of research papers in the English literature of science education present difficulties pupils have in understanding
natural selection. Studies show that children have essentialist and teleological intuitive ideas when dealing with organisms
and that these biases hinder their ability to understand the theory of evolution by natural selection. Consequently, it is
interesting to ascertain if and how the school education offered today deals with the problem, i.e., helps the children confront
these biases. To that purpose, this study answered the two following research questions: (a) How is biological evolution presented—from
the past to the present day—in the official documentation of primary school education, namely the science curricula and the
textbooks of Greece? and (b) what are the conceptions held by Greek primary school teachers of the concepts of evolutionary
theory and relevant issues that they have to teach? Our research found that not only are the intuitive ideas not “confronted”
but they are also “affirmed” in Greek primary education. This phenomenon, as some other international studies have shown,
must not be only a Greek one. A drastic change in the content and structure of primary school curricula and the training of
educators is necessary in order to improve and facilitate the teaching of biological evolution. 相似文献
16.
Feeding experiment on nine feral minkMustela vison Schreber, 1777 was carried out to find differences in digestibility of particular prey types. The values of correction factors
(CF), which show the ratio between consumed prey biomass and undigested remains, were calculated for seven food types. The
experiment revealed that results obtained by commonly used percentage of occurrence methods differed from the real intake
of food. Food types which were intensively digested were underestimated by percentage of occurrence methods and prey which
had hardly digestive elements of their body were overestimated. The calculated values of CF are as follows: crayfish — 14.8,
fish — 30.8, frog — 61.3, small passerine bird — 17.2, chicken — 41.3, rodent — 17.3, egg — 687.5. The variability in CF values
did not depend on mink individuals but could be explained by the mean weight of prey items eaten by mink. The positive correlation
between the prey size and its digestibility was recorded for crayfish, fish and chicken. The biomass of frog, passerine and
rodent remains was not related to the body mass of eaten prey. The use of evaluated correction factors enables more accurate
estimates of the food composition of wild living mustelids. 相似文献
17.
Richard M. Weinshilboum 《Cellular and molecular neurobiology》2006,26(4-6):537-559
1. Pharmacogenomics is the study of the role of inheritance in variation in the drug response phenotype—a phenotype that can vary from adverse drug reactions at one end of the spectrum to lack of therapeutic efficacy at the other.2. The thiopurine S-methyltransferase (TPMT) genetic polymorphism represents one of the best characterized and most clinically relevant examples of pharmacogenomics. This polymorphism has also served as a valuable “model system” for studies of the ways in which variation in DNA sequence might influence function.3. The discovery and characterization of the TPMT polymorphism grew directly out of pharmacogenomic studies of catechol O-methyltransferase (COMT), an enzyme discovered by Julius (Julie) Axelrod and his coworkers.4. This review will outline the process by which common, functionally significant genetic polymorphisms for both COMT and TPMT were discovered and will use these two methyltransferase enzymes to illustrate general principles of pharmacogenomic research—both basic mechanistic and clinical translational research—principles that have been applied to a series of genes encoding methyltransferase enzymes. 相似文献
18.
Chattopadhyay MK 《Journal of biosciences》2006,31(1):157-165
Survival of bacteria at low temperatures provokes scientific interest because of several reasons. Investigations in this area
promise insight into one of the mysteries of life science —namely, how the machinery of life operates at extreme environments.
Knowledge obtained from these studies is likely to be useful in controlling pathogenic bacteria, which survive and thrive
in cold-stored food materials. The outcome of these studies may also help us to explore the possibilities of existence of
life in distant frozen planets and their satellites. 相似文献
19.
Nutrient cycling and foodwebs in Dutch estuaries 总被引:5,自引:4,他引:1
P. H. Nienhuis 《Hydrobiologia》1993,265(1-3):15-44
In this review several aspects of the functioning of the Dutch estuaries (Ems-Dollard, Wadden Sea, Oosterschelde, Westerschelde,
Grevelingen and Veerse Meer) have been compared. A number of large European rivers (especially Rhine) have a prevailing influence
on the nutrient cycling of most Dutch estuaries. Owing to the increased loading of the estuaries with nitrogen and phosphorus
compounds, effects of eutrophication on the biological communities could be demonstrated, mainly in the western Wadden Sea.
The causality, however, of the relation between increased nutrient loading and increased biomass and production of primary
producers in the turbid tidal Dutch ecosystems is questioned. The most obvious biological effects of eutrophication have been
observed in a non-tidal brackish lagoon, Veerse Meer.
The estuarine food web received major attention. Budget studies of the main primary producers revealed a dominance of phytoplankton
in all Dutch estuaries, followed by microphytobenthos in the tidal systems and macrophytes in the lagoons. The quantitative
distribution of primary producers and primary and secondary consumers shows remarkable similarities along the physical and
chemical estuarine gradients, notwithstanding the large variability in space and the considerable inconstancy over time. Among
the secondary consumers (waterfowl, marine fish, larger invertebrates) the levels of organic carbon consumption — expressed
in g C m−2 y−1 — are almost the same, when tidal estuaries are compared with non-tidal lagoons, notwithstanding the fact that the consumer
populations show large qualitative differences. The transfer from primary consumers to secondary consumers reveals a bottle
neck: especially during late winter, when macrozoobenthos reaches its lowest biomass, food may be a serious limiting resource
for large numbers of migratory waders foraging on the intertidal flats. The consequences of the Deltaplan, the closure of
several estuaries in the southwest of the Netherlands and their subsequent transfer into non-tidal lagoons, offer complicated
case studies of ecosystem changes. Several examples of long-term trends in ecosystem development in Grevelingen lagoon have
been discussed. 相似文献
20.
Humanity's dependence on ecosystem support is “mentally hidden” to large segments of society; it has no price in the market
and is seldom accounted for in decision making. Similarly, the needs of ecosystems for fresh water for generation of nature's
services are largely invisible. Freshwater assessments predominantly have focused on human uses of liquid water in rivers,
lakes, and reservoirs. We estimated the spatial appropriation of terrestrial and marine ecosystems—the ecological footprint—of
the 85 million inhabitants in the Baltic Sea drainage basin with regard to consumption of food and timber and waste assimilation
of nutrients and carbon dioxide. We also estimated the amount of fresh water—the water vapor flow—that the inhabitants depend
upon for their appropriation of these ecosystem services. The ecological footprint estimate corresponds to an area as large
as 8.5–9.5 times the Baltic Sea and its drainage basin with a per capita ecosystem appropriation of 220,000–250,000 m2. This large estimate is mainly attributed to carbon sequestering by marine ecosystems and forests. The water vapor flow of
the ecological footprint of forests, wetlands, agriculture, and inland water bodies for making the human appropriation of
ecosystem services possible is estimated at 1175–2875 km3 y−1. Human dependence on water vapor flows for ecosystem services is as great as 54 times the amount of freshwater runoff that
is assessed and managed in society. Decision making on an increasingly human-dominated planet will have to address explicitly
the critical interdependencies between freshwater flows and the capacity of ecosystems to generate services. We advocate a
dynamic ecohydrological landscape-management approach upstream and downstream in watersheds to reduce unintentional impacts,
irreversible change, and further loss of freshwater resources, ecosystem services, and resilience.
Received 6 October 1998; accepted 30 March 1999. 相似文献