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233 Uppsatser om Toxic Escherichia coli-genes - Sida 13 av 16
Blood compatibility of biomaterials made of recombinant spider silk
Native spider silk is an attractive lightweight natural polymeric material with a unique combination of strength, extendibility and flexibility. Synthetic, recombinant spider silk is an attractive biomaterial with several possible fields of application.
When a foreign material is introduced to blood, this can for example cause unwanted coagulation and complement activation.
The aim of this study was to investigate if coatings of heparin or albumin could improve the blood compatibility of films of recombinant spider silk and to develop an initial method to do so. Hypothetically, objects like pacemakers, stents and dental implants could be covered with spider silk films of high blood compatibility to reduce potentially harmful foreign body reactions caused by the immune defense. Increased blood compatibility would likely lead to improvements for both the individual patients and the society thanks to reduced load on healthcare institutions.
Our objective was to assess the blood compatibility of both functionalized and non-functionalized recombinant spider silk by evaluating coagulation and activation of the complement system of the immune defense.
Coagulation was evaluated visually on glass slides and complement activation was analyzed by measuring the concentration of the complement system mediator C3a in blood samples that had been exposed to the different materials.
This study introduces a non-toxic and easy performed method of improving the blood compatibility of recombinant spider silk films by adding a heparin coating.
Heparin coated surfaces had statistically significantly higher blood compatibility than uncoated surfaces. The effects of albumin coating of films were less clear compared to the results of heparin coated films.
Complement activation could not be evaluated because of high activation in all samples prior contact with the materials that were included in the study..
Spridning av släckvattenpartiklar : En studie på spridning av partiklar genererade från brand
During a fire large amounts of particles and unhealthy agents occur. Polyaromatic hydrocarbons (PAH) and toxic metals are examples among many others. These agents have a capacity to bond to particles and when the fire is extinguished, the particles can be transferred with the extinguish water into the soil and to the groundwater.Recent studies in particles have been conducted. A study by Ulrika Iverfelt (2014) reviled that the particles from a fire contained large amounts of both PAH and metals, which is consistent with earlier analyses. Her column experiments with particles in the size ? 11 microns and ?100 microns in silica sand, reviled that the larger particles was immobilized because the transportation was influenced by sieving or physiochemical particle and surface interactions.The transport of the particles in soil and groundwater is regulated by two main mechanisms: physiochemical surface interactions and straining.
Species diversity and geographical distribution of Fusarium species on winter wheat in two regions in Sweden
Various Fusarium species causes some of the most common cereal diseases worldwide. Besides the yield losses that can be a result of these diseases, strains from several Fusarium species can produce mycotoxins, some very toxic. The aim of this study was to investigate which Fusarium species and how many that occurred in winter wheat grains from Mälardalen and Kalmar län, if there was any difference in the distribution of Fusarium fungi between the regions and the potential within species to produce mycotoxins belonging to the group trichothecenes. Winter wheat grains collected in 2009 from ten fields (unsprayed plots) in the two regions were analysed for Fusarium species. PCR was used to amplify the TEF region where after the samples were sequenced.
Biosensorsystem fo?r o?vervakning av vattenkvalitet
Sweden's drinking water quality is considered to be high partly due to a high quality of the raw water and a well developed sewage infrastructure. Despite this, there is water contamination that could be prevented by installation of a sophisticated early warning system. Some of the major players in the production of drinking water have already invested in different types of early warning systems to ensure drinking water of high quality. There are various forms of early warning systems where automatic monitoring of E. Coli is an interesting alternative.
Fermentation of lignocellulosic material by the alternative industrial ethanol yeast Dekkera bruxellensis
Bioethanol is one alternative energy fuel that can be produced from different types of biomass. Second generation bioethanol comes from fermentation of lignocellulosic material and can be seen as a more environmental friendly alternative as e.g. forest residues and agricultural by-products are used. To be able to use lignocellulosic biomass in ethanol production, it has to be subjected to different treatments first. In this study, aspen sawdust was used as lignocellulosic material.
Inappetens hos katt ? omvårdnadsbehandlingar med fokus på beröring
Particular to the cat among our pets is its´ unique nutritional needs and metabolism. The cat cannot produce some nutrients by themselves and must get them through their diet. This means that the cat quickly can suffer from various diseases unless the nutritional needs are covered. In those cases where man is completely in control of the cat?s diet, the right knowledge is crucial for the cat?s wellbeing.
Växters förmåga att ackumulera metaller : Vass, bredkaveldun och gäddnate i Bergviks dagvattendamm
AbstractSurface-water includes different kinds of pollutants from traffic and roads. To prevent these pollutants to reach nearby lakes one can construct surface-water ponds on locations with heavy traffic. At Bergviks shopping centre in Karlstad, two ponds, one smaller and one bigger has been constructed in order to decrease the pollutant pressure from the receiving waters of Kattfjorden. Several heavy metals are essential for plants and animals in low concentration but when they occur in higher concentrations, they become toxic to the organism. The larger pond at Bergviks shopping centre has a sedimentation function so the heavy metals sink to the bottom thereby not releasing directly in to Kattfjorden.
Molekylärgenetisk analys av dilaterad cardiomyopati hos hund :
Canine dilated cardiomyopathy (DCM) is a disease with high morbidity and mortality and with a high prevalence in certain breeds. Predominatly large breeds are affected, such as Great danes, Newfoundlands, Deerhounds and Dobermanns. One exception is Cocker spaniels, where both American and English Cocker spaniels are affected in a quite high frequency.
Cardiomyopathy is characterised as a disease that affects the myocardium and gives an impaired heart function. To diagnose DCM following criteria have to be observed:
1. Dilation of the left ventricle.
2. Reduced systolic heart function.
3. Increased sphericity of the left ventricle.
To be certain of the diagnosis, alternative reasons for the symptoms such as lung- and heart diseases with other etiologies have to be excluded
Two different types of DCM have been found upon histological examination.
VTEC, smittskydd på gårdsnivå
Verotoxinproducerande E. coli är en vatten- och livsmedelsburen patogen med nötkreatur som reservoar. Bakterien ger hos människa upphov till en enterohemorragisk sjukdom, i vissa fall med HUS, hemolytiskt uremiskt syndrom, som följd. HUS är mycket allvarligt och den största anledningen till att barn drabbas av akut njursvikt. Bakterien smittar fekal-oralt och boskap och människor som blivit infekterade kan utskilja mycket stora mängder bakterier i sin avföring.
Antibiotic resistance associated with bacteria in irrigation water : a case study of irrigation ponds in Southern Sweden
The
focus
of
this
project
was
to
characterize
the
occurrence
of
ESBL-?producing
bacteria
in
two
irrigation
water
ponds
in
Southern
Sweden.
Samples
were
taken
from
two
ponds
nearby
each
other,
from
which
analyses
were
made
based
on
levels
of
community
and
individual
isolates.
Community
samples
were
used
for
attempts
for
characterization
of
resistance
patterns
in
irrigation
water
using
the
Omnilog
PM-?plate
system.
The
growth
of
community
microbiota
in
the
presence
of
the
following
antibiotic
substances
was
assessed;
amikacin,
gentamicin,
kanamycin,
penicillin
G,
ampicillin,
piperacillin,
trimethoprim,
potassium
tellurite
and
ciprofloxacin.
Isolates
were
pure
cultured
using
semi-?selective
media:
LB,
Rainbow
Agar,
mEnterococcus,
0.1
TSA
and
VRBD.
A
total
of
177
isolates
were
isolated
randomly.
Each
isolate
was
identified
using
the
Omnilog
GENIII-?system
of
biochemical
characterization.
Further,
the
isolates
were
tested
on
Brilliance
ESBL-?agar
for
their
ability
to
grow.
Out
of
the
total
number
of
isolates,
30
were
selected,
preferably
Enterobacteriaceae
or
Pseudomonas
spp.,
based
on
their
high
similarity
to
library
strain
during
the
identification
in
the
Omnilog-?system.
These
were
further
characterized
using
Etest-?sticks.
Three
selected
strains
were
picked
for
further
analyses
using
exogenous
isolation
for
attempts
to
simulate
horizontal
gene
transfer,
and
Omnilog
PM-?panels
containing
various
antibiotics
of
interest.
Selections
of
samples
were
chosen
for
molecular
tests
targeting
plasmid-?borne
resistance
genes
CTX-?M1,
CTX-?M2
and
SHV.
The
method
for
assessing
community-?resistance
patterns
showed
ambiguous
data
that
was
difficult
to
interpret;
further
optimization
is
recommended.
For
all
tested
PM-?plates,
generally
greatest
differences
between
substances
were
found
among
wells
with
the
strongest
concentration
of
antibiotic
substance.
A
total
of
175
isolates
displayed
ability
to
grow
on
ESBL-?agar.
Etests
confirmed
ability
of
isolates
to
resist
many
?-?lactam
antibiotics
and
many
were
clinically
resistant
to
certain
substances.
No
plasmids
were
transferred
during
exogenous
isolation.
During
molecular
tests,
a
few
matches
were
found
for
the
CTX-?M1
gene.
Isolates
analyzed
with
Omnilog
PM-?plates
showed
resistance
to
most
compounds
tested.
The
isolates
showed
greatest
resistance
toward
penicillin
G,
ampicillin,
amikacin,
kanamycin
and
trimethoprim.
In
the
study,
it
was
established
that
resistance
among
bacteria
was
frequently
occurring
in
the
irrigation
water,
and
?-?lactamase
producing
bacteria
was
very
common.
Extended
studies
are
needed
to
assess
the
frequency-?
and
occurrence
of
horizontal
gene
transfer
(HGF)
in
this
environment.
Although
some
potential
corresponding
data
is
found,
it
is
at
this
point
not
possible
to
determine
whether
the
resistances
are
due
to
antibiotics
used
in
veterinary
medicine,
human
medicine
or
one
additional
reason
is
travel
and
trade.
in
irrigation
water
using
the
Omnilog
PM-?plate
system.
The
growth
of
community
microbiota
in
the
presence
of
the
following
antibiotic
substances
was
assessed;
amikacin,
gentamicin,
kanamycin,
penicillin
G,
ampicillin,
piperacillin,
trimethoprim,
potassium
tellurite
and
ciprofloxacin.
Isolates
were
pure
cultured
using
semi-?selective
media:
LB,
Rainbow
Agar,
mEnterococcus,
0.1
TSA
and
VRBD.
A
total
of
177
isolates
were
isolated
randomly.
Each
isolate
was
identified
using
the
Omnilog
GENIII-?system
of
biochemical
characterization.
Further,
the
isolates
were
tested
on
Brilliance
ESBL-?agar
for
their
ability
to
grow.
Out
of
the
total
number
of
isolates,
30
were
selected,
preferably
Enterobacteriaceae
or
Pseudomonas
spp.,
based
on
their
high
similarity
to
library
strain
during
the
identification
in
the
Omnilog-?system.
These
were
further
characterized
using
Etest-?sticks.
Three
selected
strains
were
picked
for
further
analyses
using
exogenous
isolation
for
attempts
to
simulate
horizontal
gene
transfer,
and
Omnilog
PM-?panels
containing
various
antibiotics
of
interest.
Selections
of
samples
were
chosen
for
molecular
tests
targeting
plasmid-?borne
resistance
genes
CTX-?M1,
CTX-?M2
and
SHV.
The
method
for
assessing
community-?resistance
patterns
showed
ambiguous
data
that
was
difficult
to
interpret;
further
optimization
is
recommended.
For
all
tested
PM-?plates,
generally
greatest
differences
between
substances
were
found
among
wells
with
the
strongest
concentration
of
antibiotic
substance.
A
total
of
175
isolates
displayed
ability
to
grow
on
ESBL-?agar.
Etests
confirmed
ability
of
isolates
to
resist
many
?-?lactam
antibiotics
and
many
were
clinically
resistant
to
certain
substances.
No
plasmids
were
transferred
during
exogenous
isolation.
During
molecular
tests,
a
few
matches
were
found
for
the
CTX-?M1
gene.
Isolates
analyzed
with
Omnilog
PM-?plates
showed
resistance
to
most
compounds
tested.
The
isolates
showed
greatest
resistance
toward
penicillin
G,
ampicillin,
amikacin,
kanamycin
and
trimethoprim.
In
the
study,
it
was
established
that
resistance
among
bacteria
was
frequently
occurring
in
the
irrigation
water,
and
?-?lactamase
producing
bacteria
was
very
common.
Extended
studies
are
needed
to
assess
the
frequency-?
and
occurrence
of
horizontal
gene
transfer
(HGF)
in
this
environment.
Although
some
potential
corresponding
data
is
found,
it
is
at
this
point
not
possible
to
determine
whether
the
resistances
are
due
to
antibiotics
used
in
veterinary
medicine,
human
medicine
or
one
additional
reason
is
travel
and
trade..
Årstidsdynamik för kvicksilver i ett sövattensediment :
The limit for mercury in fish, set by health authorities, is exceeded in about half of the lakes in Sweden. Methyl mercury (MeHg) is the most toxic form of mercury and accumulates in fish. Therefore transformation of inorganic mercury (Hg) to methylmercury (MeHg) is an important process that we need to understand in order to possibly counteract the negative effects of mercury in the environment.
The seasonal dynamics of mercury biogeochemistry is likely of great importance for the accumulation of MeHg in the aquatic food web. In thesis the chemical speciation and transformations of Hg and MeHg in bottom waters and sediments is followed in Ängessjön, a small lake located on the east coast in the middle of Sweden. The lake is not directly affected by any industrial pollution and concentrations of Hg in the sediment reflect the atmospheric deposition in this area, as well as processes taking place along the hydrological pathways from soil to lake.
Samples from sediment, bottom- and streamwater were collected in average every second month during the period Feb.
Iron bioavailability and pro- and prebiotics
Iron deficiency is one of the most frequent micronutrient deficiencies around the world. Low iron bioavailability simultaneously with a high iron requirement is a high risk factor for developing iron deficiency. Probiotics are microorganisms that confer a health benefit on the host. Prebiotics are oligosaccharides which provide a health benefit on the host due to a positive modulation of the microflora in the gut. The aim of this paper is to evaluate if there is a connection between pro-and/or prebiotics and iron bioavailability.
Kartläggning av stallbyggnader och djurhållningssystem inom mjölkproduktion ur salmonellasynpunkt
Promoters are genetic elements that facilitate the transcription of a gene and they have been found in front of non-coding RNA (ncRNA) genes in different organ-isms, e.g. the model plant Arabidopsis thaliana. A similar element, DUSE, has been found in front of ncRNAs in the social amoeba Dictyostelium discoideum and a part of this project has been to analyze the function of this putative promoter element through cloning and expression studies. A construct to analyze the func-tion of DUSE was successfully designed and introduced into D. discoideum but full expression studies were not finished because of shortage of time.
KRAV-grisar har fler ledanmärkningar än konventionellt uppfödda grisar.
Promoters are genetic elements that facilitate the transcription of a gene and they have been found in front of non-coding RNA (ncRNA) genes in different organ-isms, e.g. the model plant Arabidopsis thaliana. A similar element, DUSE, has been found in front of ncRNAs in the social amoeba Dictyostelium discoideum and a part of this project has been to analyze the function of this putative promoter element through cloning and expression studies. A construct to analyze the func-tion of DUSE was successfully designed and introduced into D. discoideum but full expression studies were not finished because of shortage of time.
Undersökning av förekomst av okända virus hos svenska fjällrävar med encefalit :
The artic fox is under threat of extermination in Europe. The population decreased strongly at the beginning of the twentieth century because of intensive hunting. The artic fox was placed under protection by law 1928 in Sweden but despite this the population has had difficultly to recover. This can depend on several reasons, but the main threats are shortage of food and competition from the red fox. Along with Norway and Finland, Sweden has carried out a project called SEFALO (Saving the Endangered Fennoscandian Alopex lagopus), whose objectives were to prevent continued decreased populationnumbers and through, for example supplementary feeding, help the population to recover.