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41.
Amirhossein Sakhteman Alireza Foroumadi Mohammad Sharifzadeh Masoud Amanlou Farhoud Rayatnia Abbas Shafiee 《Bioorganic & medicinal chemistry》2009,17(19):6908-6913
A convenient route for the synthesis of some 2-propen-1-one derivatives with E isomeric configuration is described. The activity of the synthesized compounds was evaluated through behavioral studies of apomorphine-induced licking in animal models. It was demonstrated that most of the synthesized compounds showed moderate activity in inhibition of lickings, among which 6a, was the most active compound at 30 mg/kg. 相似文献
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Kenshi Yamasaki Jun Muto Kristen R. Taylor Anna L. Cogen David Audish John Bertin Ethan P. Grant Anthony J. Coyle Amirhossein Misaghi Hal M. Hoffman Richard L. Gallo 《The Journal of biological chemistry》2009,284(19):12762-12771
Inflammation under sterile conditions is a key event in autoimmunity and
following trauma. Hyaluronan, a glycosaminoglycan released from the
extracellular matrix after injury, acts as an endogenous signal of trauma and
can trigger chemokine release in injured tissue. Here, we investigated whether
NLRP3/cryopyrin, a component of the inflammasome, participates in the
inflammatory response to injury or the cytokine response to hyaluronan. Mice
with a targeted deletion in cryopyrin showed a normal increase in Cxcl2 in
response to sterile injuries but had decreased inflammation and release of
interleukin-1β (IL-1β). Similarly, the addition of hyaluronan to
macrophages derived from cryopyrin-deficient mice increased release of Cxcl2
but did not increase IL-1β release. To define the mechanism of
hyaluronan-mediated activation of cryopyrin, elements of the hyaluronan
recognition process were studied in detail. IL-1β release was inhibited
in peritoneal macrophages derived from CD44-deficient mice, in an MH-S
macrophage cell line treated with antibodies to CD44, or by inhibitors of
lysosome function. The requirement for CD44 binding and hyaluronan
internalization could be bypassed by intracellular administration of
hyaluronan oligosaccharides (10–18-mer) in lipopolysaccharide-primed
macrophages. Therefore, the action of CD44 and subsequent hyaluronan
catabolism trigger the intracellular cryopyrin → IL-1β pathway.
These findings support the hypothesis that hyaluronan works through IL-1β
and the cryopyrin system to signal sterile inflammation.Inflammation, as defined by changes in vascular permeability and leukocyte
recruitment, is an essential step for the control of microbial invasion.
Specific microbial products trigger this process through a diverse array of
innate immune pattern recognition receptors. However, an inflammatory response
independent of infection is also an important process for maintenance of
biological homeostasis. For example, normal wound healing requires a
controlled inflammatory response to enable the recruitment of monocytes and
the release of growth factors required for repair. This response can occur in
the absence of microbial stimuli. Furthermore, inflammation and the release of
proinflammatory mediators is also associated with many diseases such as
rheumatoid arthritis and Crohn disease
(1). These diseases are not
well understood in terms of their triggers but rather are described by the
subsequent release of proinflammatory mediators. Identification of the
triggers of sterile inflammation represents an important goal with immediate
diagnostic and therapeutic significance.Recent work has begun to elucidate pathways of inflammation that occur in
the absence of microbial stimuli. Stress signals such as heat-shock proteins,
intracellular components of necrotic cells not normally seen by immune cells,
and components of the extracellular matrix have all been implicated as
endogenous triggers of injury
(2–4).
Among this group is the glycosaminoglycan hyaluronan
(HA),6 an important
structural component of the extracellular matrix that is also a common
component of bacterial surfaces. HA is synthesized at the cell surface and
typically exists as a high molecular mass polymer greater than 106
Da and composed of repeating disaccharide units of
N-acetylglucosamine and glucuronic acid
(5,
6). Unlike other
glycosaminoglycans such as heparan sulfate or chondroitin sulfates that encode
specific activity by use of a diverse disaccharide sequence, HA is not
sulfated or epimerized, and only changes in HA size, concentration, and
location affect function.We have previously developed murine models of sterile injury to identify
the innate elements that recognize and mediate sterile inflammation
(7). Our results demonstrated
that (a) the initiation of a sterile intrinsic inflammatory process
is dependent on TLR4 activation, (b) sterile injury induces HA
accumulation at the injured site, and (c) sterile intrinsic
inflammation resembles signaling events that are activated by HA. Furthermore,
we have defined a novel alternative recognition complex for HA that involves
TLR4, MD-2, and CD44 (7). Taken
together with other work associating HA and innate pattern recognition
(4,
8–10),
these observations have provided new insight into mechanisms responsible for
sterile inflammation.Recently, the NLR (nucleotide-binding domain and leucine rich
repeat-containing) family has been extensively analyzed as a group of
intracellular pattern recognition receptors
(11). NLRs have a leucine-rich
repeat that recognizes pathogen-associated molecular patterns including
bacterial cell wall components and viral nucleic acids. NOD2 and NLR family,
pyrin containing 3 (NLRP3)/cryopyrin are two of the best
characterized NLRs. NOD2 recognizes the bacterial peptidoglycan-derived
molecule muramyl dipeptide and activates the NF-κB pathway to induce
inflammatory responses (12).
Mutations of the NOD2 gene were identified in individuals with
chronic inflammatory disorders such as Crohn disease
(13,
14) and Blau syndrome
(15). Mouse knockin mutants of
NOD2, which have the same mutation in NOD2 as human patients
with Crohn disease, showed elevated proinflammatory cytokines following
muramyl dipeptide challenge or dextran sodium sulfate-induced bowel
inflammation (16).
NLRP3, also known as cyropyrin, CIAS1, NALP3, PYPAF1, forms
an “inflammasome” with ASC (apoptosis-associated speck-like
protein containing a CARD) and caspase-1 to convert pro-IL-1β to active
IL-1β (17). Mutations in
NLRP3 were identified in individuals with familial cold
autoinflammatory syndrome (FCAS), Muckle-Wells syndrome, and neonatal onset
multisystem inflammatory disease
(18–20).
These individuals have recurrent or chronic inflammatory symptoms, including
fever, arthritis, and a urticaria-like eruption characterized by neutrophilic
infiltration. In FCAS, symptoms can be elicited by cold provocation by a
mechanism that appears to be mediated through the skin
(15,
21).Because disorders associated with mutations in NLRP3 are examples
of inflammation under sterile conditions and HA has been shown to be a trigger
of sterile inflammation, we sought to further understand the mechanism of the
response to HA by examining the role of cryopyrin during injury and after
exposure to HA. Our results show that cryopyrin and IL-1β are integral to
sterile inflammation and the response to HA. These observations provide new
insight into the function of HA as a “danger signal” of
injury. 相似文献
43.
Foroumadi A Kargar Z Sakhteman A Sharifzadeh Z Feyzmohammadi R Kazemi M Shafiee A 《Bioorganic & medicinal chemistry letters》2006,16(5):1164-1167
Two series of 2- and 3-[5-(nitroaryl)-1,3,4-thiadiazol-2-ylthio, sulfinyl and sulfonyl] propionic acid alkyl esters were synthesized and screened for antituberculosis activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system. The MIC values for the compounds showing more than 90% inhibition were determined. The result of comparison between two groups of data exhibited that among the synthesized derivatives, the compound propyl 3-[5-(5-nitrothiophen-2-yl)-1,3,4-thiadiazol-2-ylthio]propionate was the most active one (MIC=1.56 microgml(-1)). 相似文献
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45.
This article evaluates selected sensitivity analysis methods applicable to risk assessment models with two-dimensional probabilistic frameworks, using a microbial food safety process risk model as a test-bed. Six sampling-based sensitivity analysis methods were evaluated including Pearson and Spearman correlation, sample and rank linear regression, and sample and rank stepwise regression. In a two-dimensional risk model, the identification of key controllable inputs that can be priorities for risk management can be confounded by uncertainty. However, despite uncertainty, results show that key inputs can be distinguished from those that are unimportant, and inputs can be grouped into categories of similar levels of importance. All selected methods are capable of identifying unimportant inputs, which is helpful in that efforts to collect data to improve the assessment or to focus risk management strategies can be prioritized elsewhere. Rank-based methods provided more robust insights with respect to the key sources of variability in that they produced narrower ranges of uncertainty for sensitivity results and more clear distinctions when comparing the importance of inputs or groups of inputs. Regression-based methods have advantages over correlation approaches because they can be configured to provide insight regarding interactions and nonlinearities in the model. 相似文献
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The promise of stem cell markers in the diagnosis and therapy of epithelial dysplasia and oral squamous cell carcinoma
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Farnaz Mohajertehran Amirhossein Sahebkar Reza Zare Nooshin Mohtasham 《Journal of cellular physiology》2018,233(11):8499-8507
Oral squamous cell carcinoma (OSCC) is the most common type of head and neck cancer. Epithelial dysplasia is often initiated in the cells and cell nuclei adjacent to the epithelial cell membrane. Reduced cell–cell adhesions enable cancer cells to detach from the tumor and disseminate to other organs. The mutations in epithelial dysplasia markers such as E‐cadherin and epithelial cell adhesion molecules (CD326) can lead to proliferation, growth and survival of the tumor cells and persistence of numerous malignancies that play a key role in epithelial dysplasia of OSCC. Accordingly, these genes can be considered prognostic markers or potential therapeutic targets for the tailored management of patients with OSCC. The gene expression profile of OSCC stem cells indicates a differential pattern that facilitates establishing a cell signature. Owing to the highly tumorigenic behavior of cancer stem cells and the role of these cells in tumor differentiation, treatment resistance, relapse, and metastasis, we reviewed the role of stem cell markers in epithelial dysplasia and OSCC. 相似文献
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