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21.
We aim to ascertain the possible involvement of functional IL10 and TNF-α promoter polymorphisms on the susceptibility to Behçet’s syndrome (BS), to examine whether IL10 and TNF-α genotypes might work synergistically influencing susceptibility to BS. IL10 ?1082G/A, ?819C/T and ?592C/A and TNF ?308G/A polymorphisms were analyzed in 102 Turkish patients with BS and 102 healthy subjects by using amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). We have found no significant associations between IL10 ?1082G/A, ?819C/T, ?592C/A, TNF-α ?308G/A polymorphisms and BS. Also, no significant correlation was found between IL10 GCC, ACC, ATA haplotypes, GCC+/GCC+, GCC+/GCC?, GCC?/GCC? genotypes. There was no significant association between combined TNF-α/IL10 genotypes and BS. Our study indicates that functional TNF-α, IL10 genotypes or combined TNF-α, IL10 genotypes do not play a role in BS susceptibility in Turkish BS patients.  相似文献   
22.

Background

Breast cancer in young women tends to have a natural history of aggressive disease for which rates of recurrence are higher than in breast cancers detected later in life. Little is known about the genetic pathways that underlie early-onset breast cancer. Here we report the discovery of DEAR1 (ductal epithelium–associated RING Chromosome 1), a novel gene encoding a member of the TRIM (tripartite motif) subfamily of RING finger proteins, and provide evidence for its role as a dominant regulator of acinar morphogenesis in the mammary gland and as an independent predictor of local recurrence-free survival in early-onset breast cancer.

Methods and Findings

Suppression subtractive hybridization identified DEAR1 as a novel gene mapping to a region of high-frequency loss of heterozygosity (LOH) in a number of histologically diverse human cancers within Chromosome 1p35.1. In the breast epithelium, DEAR1 expression is limited to the ductal and glandular epithelium and is down-regulated in transition to ductal carcinoma in situ (DCIS), an early histologic stage in breast tumorigenesis. DEAR1 missense mutations and homozygous deletion (HD) were discovered in breast cancer cell lines and tumor samples. Introduction of the DEAR1 wild type and not the missense mutant alleles to complement a mutation in a breast cancer cell line, derived from a 36-year-old female with invasive breast cancer, initiated acinar morphogenesis in three-dimensional (3D) basement membrane culture and restored tissue architecture reminiscent of normal acinar structures in the mammary gland in vivo. Stable knockdown of DEAR1 in immortalized human mammary epithelial cells (HMECs) recapitulated the growth in 3D culture of breast cancer cell lines containing mutated DEAR1, in that shDEAR1 clones demonstrated disruption of tissue architecture, loss of apical basal polarity, diffuse apoptosis, and failure of lumen formation. Furthermore, immunohistochemical staining of a tissue microarray from a cohort of 123 young female breast cancer patients with a 20-year follow-up indicated that in early-onset breast cancer, DEAR1 expression serves as an independent predictor of local recurrence-free survival and correlates significantly with strong family history of breast cancer and the triple-negative phenotype (ER, PR, HER-2) of breast cancers with poor prognosis.

Conclusions

Our data provide compelling evidence for the genetic alteration and loss of expression of DEAR1 in breast cancer, for the functional role of DEAR1 in the dominant regulation of acinar morphogenesis in 3D culture, and for the potential utility of an immunohistochemical assay for DEAR1 expression as an independent prognostic marker for stratification of early-onset disease.  相似文献   
23.
Trauma such as burns induces a hypermetabolic response associated with altered central carbon and nitrogen metabolism. The liver plays a key role in these metabolic changes; however, studies to date have evaluated the metabolic state of liver using ex vivo perfusions or isotope labeling techniques targeted to specific pathways. Herein, we developed a unique mass balance approach to characterize the metabolic state of the liver in situ, and used it to quantify the metabolic changes to experimental burn injury in rats. Rats received a sham (control uninjured), 20% or 40% total body surface area (TBSA) scald burn, and were allowed to develop a hypermetabolic response. One day prior to evaluation, all animals were fasted to deplete glycogen stores. Four days post-burn, blood flow rates in major vessels of the liver were measured, and blood samples harvested. We combined measurements of metabolite concentrations and flow rates in the major vessels entering and leaving the liver with a steady-state mass balance model to generate a quantitative picture of the metabolic state of liver. The main findings were: (1) Sham-burned animals exhibited a gluconeogenic pattern, consistent with the fasted state; (2) the 20% TBSA burn inhibited gluconeogenesis and exhibited glycolytic-like features with very few other significant changes; (3) the 40% TBSA burn, by contrast, further enhanced gluconeogenesis and also increased amino acid extraction, urea cycle reactions, and several reactions involved in oxidative phosphorylation. These results suggest that increasing the severity of injury does not lead to a simple dose-dependent metabolic response, but rather leads to qualitatively different responses.  相似文献   
24.
Substituted polyaniline/chitosan (sPANI/Ch) composites were chemically synthesized in H2SO4 and CH3COOH synthesis media. Structural and physical properties of the composites were characterized by using FTIR, SEM, TGA, UV–vis, XRD techniques, and conductivity measurements. The effect of synthesis media on morphology, thermal stability, conductivity, and crystalline properties was investigated. Chemical interactions between substituted polyanilines and chitosan were explained using FTIR spectra results. The different morphological surfaces were observed in SEM images of the composites. The size of the substituted polyaniline/chitosan (sPANI/Ch) composites was in nanoscale, and the composites synthesized in acetic acid media showed smaller structures than those of H2SO4 media and pure chitosan. It was interpreted from XRD results that the composites have amorphous structure and the PNEANI/Ch–CH3COOH composite has the highest crystallinity.  相似文献   
25.
Dagci T  Sengul G  Keser A  Onal A 《Life sciences》2011,88(17-18):746-752
AimsThe aim of this study is to determine the role of nitric oxide (NO) in neuropathic pain and the effect of embryonic neural stem cell (ENSC) transplantation on NO content in rat spinal cord neurons following spinal cord injury (SCI).Main methodsNinety adult male Sprague–Dawley rats were divided into 3 groups (n = 30, each): control (laminectomy), SCI (hemisection at T12–T13 segments) and SCI + ENSC. Each group was further divided into sub-groups (n = 5 each) based on the treatment substance (L-NAME, 75 mg/kg/i.p.; l-arginine, 225 mg/kg/i.p.; physiological saline, SF) and duration (2 h for acute and 28 days for chronic groups). Pain was assessed by tail flick and Randall–Selitto tests. Fos immunohistochemistry and NADPH-d histochemistry were performed in segments 2 cm rostral and caudal to SCI.Key findingsTail-flick latency time increased in both acute and chronic L-NAME groups and increased in acute and decreased in chronic l-arginine groups. The number of Fos (+) neurons decreased in acute and chronic L-NAME and decreased in acute l-arginine groups. Following ENSC, Fos (+) neurons did not change in acute L-NAME but decreased in the chronic L-NAME groups, and decreased in both acute and chronic l-arginine groups. NADPH-d (+) neurons decreased in acute L-NAME and increased in l-arginine groups with and without ENSC transplantation.SignificanceThis study confirms the role of NO in neuropathic pain and shows an improvement following ENSC transplantation in the acute phase, observed as a decrease in Fos(+) and NADPH-d (+) neurons in spinal cord segments rostral and caudal to injury.  相似文献   
26.
The autosomal-recessive form of popliteal pterygium syndrome, also known as Bartsocas-Papas syndrome, is a rare, but frequently lethal disorder characterized by marked popliteal pterygium associated with multiple congenital malformations. Using Affymetrix 250K SNP array genotyping and homozygosity mapping, we mapped this malformation syndrome to chromosomal region 21q22.3. Direct sequencing of RIPK4 (receptor-interacting serine/threonine kinase protein 4) showed a homozygous transversion (c.362T>A) that causes substitution of a conserved isoleucine with asparagine at amino acid position 121 (p.Ile121Asn) in the serine/threonine kinase domain of the protein. Additional pathogenic mutations-a homozygous transition (c.551C>T) that leads to a missense substitution (p.Thr184Ile) at a conserved position and a homozygous one base-pair insertion mutation (c.777_778insA) predicted to lead to a premature stop codon (p.Arg260ThrfsX14) within the kinase domain-were observed in two families. Molecular modeling of the kinase domain showed that both the Ile121 and Thr184 positions are critical for the protein's stability and kinase activity. Luciferase reporter assays also demonstrated that these mutations are critical for the catalytic activity of RIPK4. RIPK4 mediates activation of the nuclear factor-κB (NF-κB) signaling pathway and is required for keratinocyte differentiation and craniofacial and limb development. The phenotype of Ripk4(-/-) mice is consistent with the human phenotype presented herein. Additionally, the spectrum of malformations observed in the presented families is similar, but less severe than the conserved helix-loop-helix ubiquitous kinase (CHUK)-deficient human fetus phenotype; known as Cocoon syndrome; this similarity indicates that RIPK4 and CHUK might function via closely related pathways to promote keratinocyte differentiation and epithelial growth.  相似文献   
27.
Vaccination with live vaccinia virus affords long-lasting protection against variola virus, the agent of smallpox. Its mode of protection in humans, however, has not been clearly defined. Here we report that vaccinia-specific B-cell responses are essential for protection of macaques from monkeypox virus, a variola virus ortholog. Antibody-mediated depletion of B cells, but not CD4+ or CD8+ T cells, abrogated vaccine-induced protection from a lethal intravenous challenge with monkeypox virus. In addition, passive transfer of human vaccinia-neutralizing antibodies protected nonimmunized macaques from severe disease. Thus, vaccines able to induce long-lasting protective antibody responses may constitute realistic alternatives to the currently available smallpox vaccine (Dryvax).  相似文献   
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Mounting evidence suggests involvement of deregulated microRNA (miRNA) expression during the complex events of tumorigenesis. Among such deregulated miRNAs in cancer, miR-125b expression is reported to be consistently low in breast cancers. In this study, we screened a panel of breast cancer cell lines (BCCLs) for miR-125b expression and detected decreased expression in 14 of 19 BCCLs. Due to the heterogeneity of breast cancers, MCF7 cells were chosen as a model system for ERBB2 independent breast cancers to restore miR-125b expression (MCF7-125b) to investigate the phenotypical and related functional changes. Earlier, miR-125b was shown to regulate cell motility by targeting ERBB2 in ERBB2 overexpressing breast cancer cells. Here we showed decreased motility and migration in miR-125b expressing MCF7 cells, independent of ERBB2. MCF7-125b cells demonstrated profoundly decreased cytoplasmic protrusions detected by phalloidin staining of filamentous actin along with decreased motility and migration behaviors detected by in vitro wound closure and transwell migration assays compared to empty vector transfected cells (MCF7-EV). Among possible numerous targets of miR-125b, we showed ARID3B (AT-rich interactive domain 3B) to be a novel target with roles in cell motility in breast cancer cells. When ARID3B was transiently silenced, the decreased cell migration was also observed. In light of these findings, miR-125b continues to emerge as an interesting regulator of cancer related phenotypes.  相似文献   
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