排序方式: 共有158条查询结果,搜索用时 15 毫秒
101.
In this paper, the complex formation of bovine serum albumin (BSA) and polyacrylic acid (PAA) in the presence metal ions at
pH = 7 has been examined by using fluorescence and dynamic light scattering measurements. It has been observed that the most
stable complexes of polyacrylic acid and bovine serum albumin have occurred in the presence of copper(II) ions. The other
ions have the ability to form weak complexes between polyions and bovine serum albumin. To prior characterizing the interaction
between bovine serum albumin and polyacrylic acid, the dynamic light scattering technique have been applied to determine the
intensity-size distributions of the solutions of bovine serum albumin, polyacrylic acid, and ternary mixtures containing various
molar ratios of bovine serum albumin to polyacrylic acid (the molar ratios of bovine serum albumin to polyacrylic acid has
been taken equal to 0.5, 1.0, 1.5, 2.0 and 2.5) prepared at different molar ratios of copper(II) ions/acrylic acid unit. When
the molar ratio of copper(II) ions to acrylic acid in the ternary mixtures has been lower than and equals to 0.3, two peaks
have been observed in the curves of the intensity-size distributions due to contents of free bovine serum albumin and ternary
complexes of polyacrylic acid-copper(II)-bovine serum albumin whereas when the molar ratio of copper(II) ions to acrylic acid
equals to 0.4, the hydrodynamic diameter has pointed out only one peak. This result indicates that soluble and stable ternary
complexes has occurred when the molar ratio of copper(II) ions to acrylic acid has been taken equal to 0.4. 相似文献
102.
Sigríeur?Bj?rnsdóttir Elfa?Agustsdóttir Anne-Lie?Blomstr?m Inga-Lena??rde??str?m Louise?Treiberg?Berndtsson Vilhjálmur?Svansson Jonas?Johansson?WensmanEmail author 《Acta veterinaria Scandinavica》2013,55(1):77
Background
In a stable of eight horses in Northern Iceland, six horses presented with clinical signs, such as ataxia and reduced appetite, leading to euthanasia of one severely affected horse. Serological investigations revealed no evidence of active equine herpes virus type 1 infection, a common source of central nervous system disease in horses, nor equine arteritis virus and West Nile virus. Another neurotropic virus, Borna disease virus, was therefore included in the differential diagnosis list.Findings
Serological investigations revealed antibodies against Borna disease virus in four of five horses with neurological signs in the affected stable. One horse without clinical signs was seronegative. Four clinically healthy horses in the stable that arrived and were sampled one year after the outbreak were found seronegative, whereas one of four investigated healthy horses in an unaffected stable was seropositive.Conclusions
This report contains the first evidence of antibodies to Borna disease virus in Iceland. Whether Borna disease virus was the cause of the neurological signs could however not be confirmed by pathology or molecular detection of the virus. As Iceland has very restricted legislation regarding animal imports, the questions of how this virus has entered the country and to what extent markers of Bornavirus infection can be found in humans and animals in Iceland remain to be answered.103.
Exposure to oxidative stress causes health problems, including sensory neuron neuropathy and pain. Rotenone is a toxin used
to generate intracellular oxidative stress in neurons. However, the mechanism of toxicity in dorsal root ganglion (DRG) neurons
has not been characterized. Melastatin-like transient receptor potential 2 (TRPM2) channel activation and inhibition in response
to oxidative stress, ADP-ribose (ADPR), flufenamic acid (FFA) and 2-aminoethoxydiphenyl borate (2-APB) in DRG neurons are
also not clear. We tested the effects of FFA and 2-APB on ADPR and rotenone-induced TRPM2 cation channel activation in DRG
neurons of rats. DRG neurons were freshly isolated from rats and studied with the conventional whole-cell patch-clamp technique.
Rotenone, FFA and 2-APB were extracellularly added through the patch chamber, and ADPR was applied intracellularly through
the patch pipette. TRPM2 cation currents were consistently induced by ADPR and rotenone. Current densities of the neurons
were higher in the ADPR and rotenone groups than in control. The time courses (gating times) in the neurons were longer in
the rotenone than in the ADPR group. ADPR and rotenone-induced TRPM2 currents were totally blocked by 2-APB and partially
blocked by FFA. In conclusion, TRPM2 channels were constitutively activated by ADPR and rotenone, and 2-APB and FFA induced
an inhibitory effect on TRPM2 cation channel currents in rat DRG neurons. Since oxidative stress is a common feature of neuropathic
pain and diseases of sensory neurons, the present findings have broad application to the etiology of neuropathic pain and
diseases of DRG neurons. 相似文献
104.
A new locally produced P-inactivation agent, Z2G1, was tested on sediment cores from Lake Okaro, New Zealand, for phosphorus
(P) removal efficacy and any non-target side effects prior to a whole lake trial to manage internal P loading. Z2G1 is a granular
product which settles rapidly, and was designed as a sediment capping material. It is a modified zeolite which acts as a carrier
for the aluminium (Al)-based P-binding agent. It was found to have a high affinity for P and did not release Al into the water
column. Continuous-flow incubation study results showed that a thin layer of Z2G1 (~2 mm) could completely block the release
of P from the sediment under aerobic and anoxic conditions, and remove P from the overlying water in contact with the capping
layer. The Z2G1 capping layer neither released metals itself nor did it induce the release of metals from the sediments, and
the zeolite substrate absorbed arsenic and mercury from the geothermally influenced Lake Okaro sediments. In general, zeolites
are strong cation absorbers and the zeolite substrate of Z2G1 absorbed ammoniacal nitrogen, making it the only sediment capping
material to actively remove both P and N. There were, however, indications of a suppression effect on microbial denitrification
by the Z2G1 capping layer under aerobic conditions. Overall, the Z2G1 sediment capping material is a highly effective P-inactivation
agent which might be a useful material for managing internal P loads in eutrophic lakes. 相似文献
105.
Ozbek S 《Protoplasma》2011,248(4):635-640
Nematocysts are the taxon-defining features of all cnidarians including jellyfish, sea anemones, and corals. They are highly
sophisticated organelles used for the capture of prey and defense. The nematocyst capsule is produced within a giant post-Golgi
vesicle, which is continuously fed by proteins from the secretory pathway. Mature nematocysts consist of a hollow capsule
body in which a long tubule is coiled up that, upon discharge, is expelled in a harpoon-like fashion. This is accompanied
by the release of a toxin cocktail stored in the capsule matrix. Nematocyst discharge, which is one of the fastest processes
in biology, is driven by an extreme osmotic pressure of about 150 bar. The molecular analysis of the nematocyst has from the
beginning indicated a collagenous nature of the capsule structure. In particular, a large family of unusual minicollagens
has been demonstrated to form the highly resistant scaffold of the capsule. Recent findings on the molecular composition of
Hydra nematocysts have confirmed the notion of a specialized extracellular matrix, which is assembled during an intracellular secretion
process to form the most complex predatory apparatus at the cellular level. 相似文献
106.
Süleyman Can Öztürk Hüseyin İrfan Balık Selda Kayalak Balık Gökhan Kızılcı Ömür Duyar Sami Doğanlar Anne Frary 《Tree Genetics & Genomes》2017,13(5):113
European hazelnut (Corylus avellana L.) is an economically and nutritionally important nut crop with wild and cultivated populations found throughout Europe and in parts of Asia. This study examined the molecular genetic diversity and population structure of 402 genotypes including 143 wild individuals, 239 landraces, and 20 cultivars from the Turkish national hazelnut collection using simple sequence repeat (SSR) markers. A total of 30 SSR markers yielded 407 polymorphic fragments. Diversity analysis of the Turkish hazelnut genotypes indicated that they fell into three subpopulations according to ad hoc statistics and neighbor-joining algorithm. Although all cultivars clustered together, they overlapped with the wild accessions and landraces. Thus, the dendrogram, principal coordinate, and population structure analyses suggest that they share the same gene pool. A total of 78 accessions were selected as a core set to encompass the molecular genetic and morphological diversity present in the national collection. This core set should have priority in preservation efforts and in trait characterization. 相似文献
107.
Protein SYCP2 provides a link between transverse filaments and lateral elements of mammalian synaptonemal complexes 总被引:1,自引:0,他引:1
Synaptonemal complexes (SCs) are evolutionarily conserved meiosis-specific nuclear structures critically involved in synapsis,
recombination, and segregation of homologous chromosomes. SCs are proteinaceous structures composed of (a) two lateral elements
(LEs), to which the chromatin of the homologs is attached, (b) numerous transverse filaments (TFs) that link the LEs, and
(c) a central element (CE). Major protein components of mammalian SCs are the TF protein SYCP1 and the LE proteins SYCP2 and
SCYP3. How SCs become assembled is presently poorly understood, in particular, it is not known how TFs assemble at the plane
of LEs to interconnect the homologous chromosomes. Therefore, we have investigated possible interactions between SYCP1 and
other SC proteins. In immunoprecipitation experiments we could find that SYCP1 and SYCP2 interact in extracts of meiotic cells.
Using the yeast two-hybrid system, we were able to demonstrate that the C-terminus of SYCP1 directly interacts with SYCP2.
These results were confirmed by different interaction traps. Furthermore, we could narrow down the interacting domain of the
SYCP2 molecule to its C-terminal region. We propose that SYCP2 acts as a linker between SYCP1 and SYCP3 and therefore would
be the missing connecting link between LEs and TFs essential for proper chromosome synapsis. 相似文献
108.
The S gene region of the hepatitis B virus (HBV) is responsible for the expression of surface antigens and includes the ‘a’-determinant
region. Thus, mutation(s) in this region would afford HBV variants a distinct survival advantage, permitting the mutant virus
to escape from the immune system. The aim of this study was to search for mutations of the S gene region in different patient groups infected with genotype D variants of HBV, and to analyse the biological significance of these mutations. Moreover, we investigated S gene mutation inductance among family members. Forty HBV-DNA-positive patients were determined among 132 hepatitis B surface
antigen (HbsAg) carriers by the first stage of seminested PCR. Genotypes and subtypes were established by sequencing of the
amplified S gene regions. Variants were compared with original sequences of these serotypes, and mutations were identified.
All variants were designated as genotype D and subtype ayw3. Ten kinds of point mutations were identified within the S region. The highest rates of mutation were found in chronic hepatitis patients and their family members. The amino acid mutations
125 (M → T) and 127 (T → P) were found on the first loop of ‘a’-determinant. The other consequence was mutation inductance
in a family member. We found some mutations in the S gene region known to be stable and observed that some of these mutations
affected S gene expression. 相似文献
109.
Fulya Ergun Ergül Sayit Sargın Gaye Öngen Fazilet Vardar Sukan 《World journal of microbiology & biotechnology》2011,27(1):107-114
In a previous work it was reported adapted Trametes versicolor FPRL 28A INI culture was used to treat undiluted olive mill wastewater (OMW) without addition of any nutrients with significant
amount of total phenolics were removed. However, decolorization was not so pronounced. Therefore, the aim of this study is
to enhance the efficiency of dephenolization and decolorization of the primary treatment with adapted Trametes versicolor, incorporating a secondary biological treatment step using different microorganisms with sequential batch and co-culture applications.
Through sequential batch applications Funalia trogii ATCC 20080 was found to have a higher potential in terms of total phenolics removal and decolorization amongst the tested
organisms and better results were obtained from sequential batch applications as compared to co-culture experiments. In sequential
batch applications, up to 91% total phenolics were removed and 64% decolorization was achieved after 24 days with 20% (v/v)
inoculation rate of F. trogii when malt extract broth was used in inoculum preparation. In addition, significant accumulation of laccase (2019 ± 121.13Ul−1) and manganese peroxidase (463 ± 33.89 Ul−1) activities were attained. In co-culture applications highest total phenolics removal and decolorization were 78 and 39%,
respectively, with non-adapted T. versicolor, whereas highest laccase and manganese peroxidase acitivities were obtained with F. trogii as 2219 Ul−1 ± 176.14. and 513 ± 4.12 Ul−1, respectively. 相似文献
110.
Gümüş M Yüksel H Evliyaoğlu O Kapan M Böyük A Önder A Aldemir M 《Biological trace element research》2011,143(1):386-393
Ellagic acid (EA) is a natural polyphenolic compound. Although, modulator effects of EA on copper (Cu) and zinc (Zn) levels
in some liver diseases have been reported in experimental animals, its effects in obstructive jaundice (OJ) has not been clarified.
We aimed to evaluate potential effects of EA on Cu and Zn levels in liver and serum of cholestatic rats. Forty Wistar albino
rats were equally divided into four groups. First group was used as controls. Second group received EA (60 mg−1 kg−1 day−1) for 8 days. Third was OJ group, and fourth group was OJ plus EA group. After 8 days, blood and liver samples were obtained.
Higher serum and liver Cu and lower serum and liver Zn levels were found in OJ group (p < 0.05) compared with other groups. However, these differences reached to significant levels for Cu in serum and for Zn in
lever. Higher serum copper levels were decreased, and lower liver Zn levels were increased by EA treatment in cholestatic
rats (p < 0.05). Also, higher Cu/Zn ratio in OJ group was decreased by EA treatment both in liver (p < 0.05) and in serum (p < 0.05). Significantly higher serum bilirubin, alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase
values were found in OJ and OJ + EA groups compared with the control and EA groups (p < 0.05). In conclusion, result of the current study indicated that ellagic acid has modulator effects on Cu and Zn levels
in liver and serum of cholestatic rats. 相似文献