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11.

Background

In cancer cells, apoptosis is an important mechanism that influences the outcome of chemotherapy and the development of chemoresistance. To find the genes involved in chemoresistance and the development of gastric cancer, we used the suppression subtractive hybridization method to identify the genes that are overexpressed in gastric cancer tissues compared to normal gastric tissues.

Results

In the suppression subtractive hybridization library we constructed, the most highly overexpressed genes were humanin isoforms. Humanin is a recently identified endogenous peptide that has anti-apoptotic activity and has been selected for further study due to its potential role in the chemoresistance of gastric cancer. Upregulation of humanin isoforms was also observed in clinical samples by using quantitative real-time PCR. Among the studied isoforms, humanin isoform 3, with an expression level of 4.166 ± 1.44 fold, was the most overexpressed isoform in GC.

Conclusions

The overexpression of humanin in gastric cancer suggests a role for chemoresistance and provides new insight into the biology of gastric cancer. We propose that humanin isoforms are novel targets for combating chemoresistance in gastric cancer.  相似文献   
12.
Background: Most children in need of cardiac pacemakers remain dependent on the function of the permanent from childhood to adulthood. We sought to evaluate and compare the function between epicardial and endocardial pacemakers in pediatric groups with different conditions. Methods: Between 2012 and 2018, this single-canter study evaluated 44 pediatric patients with indications for epicardial or endocardial pacemakers. Results: The 2 groups, at a median age of 5 (0.1–16) years, were compared concerning the characteristics of the leads used (n = 80: bipolar, unipolar, steroid-eluting, and non–steroid-eluting), survival data, and complications. The reason for pacemaker implantation was congenital complete heart block in 11 (25%) cases and postoperative heart block in 33 (75%) cases. The commonest congenital heart disease accompanied by postoperative block was the ventricular septal defect. In the endocardial lead group, the mean ventricular pacing threshold immediately after the implantation and during the follow-up was less than that in the epicardial lead group (0.75 vs. 0.81 V; P = 0.01 and 0.8 vs. 2.4 V; P = 0.001). During the follow-up, the mean battery longevity was better in the endocardial group (last visit: 6.7 endocardial vs. 3.3 years epicardial). Lead failure was commoner in the epicardial pacemaker, and chronic high-pacing threshold pattern was seen in 14 patients in this group. After 3 years, freedom from lead failure was 94% and 63% in the endocardial and epicardial leads. Conclusions: Pacemakers with endocardial bipolar steroid-eluting leads showed better lead characteristics regarding survival and battery longevity than epicardial pacemakers without these lead characteristics. An appropriate pacemaker type should be selected based on the patient’s condition.  相似文献   
13.
Cyproterone acetate (CPA) is used to treat various skin disorders such as acne, hirsutism, and alopecia. Due to the limited skin penetration of CPA, nanostructured lipid carriers (NLCs) with different size ranges were considered in this study in order to enhance skin penetration and to target hair follicles. Drug loading, drug release and morphological assessment were evaluated for each targeted size (100, 300, and 600?nm). Ex vivo skin penetration was also investigated using Franz diffusion cells. Finally, in vivo follicular targeting was evaluated using rhodamine B-loaded micro and nanoparticles. Results revealed that 60–85% of drug was slowly released from lipid nanoparticles within 72?h. CPA-NLC with average diameter of 600?nm had better penetration and deposition in dermis-epidermis layer, also CPA-NLC 100 and 300?nm significantly increased drug penetration in dermis-epidermis in comparison to free CPA. Follicular targeting results revealed that NLC 300?nm had the best accumulation capacity in hair follicles. CPA-NLC with average diameter of 300?nm could be a promising topical novel drug delivery system for specific targeting of hair follicles and sebaceous glands to treat androgenic skin disorders such as acne, hirsutism, and alopecia.  相似文献   
14.
15.
Klinefelter Syndrome (KS) is the most common sex chromosome aneuploidy in men and is characterized by the presence of an additional X chromosome (XXY). In some Klinefelter males, certain traits may be feminized or shifted from the male-typical pattern towards a more female-typical one. Among them might be partner choice, one of the most sexually dimorphic traits in the animal kingdom. We investigated the extent of feminization in XXY male mice (XXYM) in partner preference and gene expression in the bed nucleus of the stria terminalis/preoptic area and the striatum in mice from the Sex Chromosome Trisomy model. We tested for partner preference using a three-chambered apparatus in which the test mouse was free to choose between stimulus animals of either sex. We found that partner preference in XXYM was feminized. These differences were likely due to interactions of the additional X chromosome with the Y. We also discovered genes that differed in expression in XXYM versus XYM. Some of these genes are feminized in their expression pattern. Lastly, we also identified genes that differed only between XXYM versus XYM and not XXM versus XYM. Genes that are both feminized and unique to XXYM versus XYM represent strong candidates for dissecting the molecular pathways responsible for phenotypes present in KS/XXYM but not XXM. In sum, our results demonstrated that investigating behavioral and molecular feminization in XXY males can provide crucial information about the pathophysiology of KS and may aid our understanding of sex differences in brain and behavior.  相似文献   
16.
In this research, an environmental friendly, green and efficient sample preparation method using vortex-assisted microextraction based on a deep eutectic solvent (VAME-DES) followed by graphite furnace atomic absorption spectrometry (GFAAS) was developed for the preconcentration and determination of As(iii)/As(v) and total inorganic arsenic in soil and vegetables irrigated with treated municipal wastewater from Tehran and Kermanshah, Iran. In the proposed method, a novel DES, characterized by its low density, was prepared by mixing choline chloride and citric acid monohydrate at a molar ratio of 1 : 1. Under optimal conditions, the proposed method enabled the achievement of a good enrichment factor of 175. The calibration graph was linear in the range of 0.3–100 μg kg−1 and the limit of detection (LOD) was 0.10 μg kg−1. The repeatability and reproducibility of the method based on seven replicate measurements of 50 μg kg−1 As(iii) in analysed samples were 4.2% and 6.5, respectively. The relative recoveries from soil and vegetables that were spiked with different levels of As(iii) and As(v) were 94.2–104.3 and 91.0–107.0%, respectively. The main advantage of the proposed method is the use of a non-toxic and non-volatile DES instead of volatile organic solvents. The accuracy of the proposed procedure was also assessed by the speciation of arsenic in two standard reference materials (GBW10014 cabbage and GBW10015 spinach). The extraction methodology is simple, rapid, cheap and green, since only small amounts of non-toxic solvents are necessary.

An efficient method using vortex-assisted microextraction based on a deep eutectic solvent followed by graphite furnace atomic absorption spectrometry was developed for the determination of arsenic species in soil and vegetables irrigated with treated wastewater.  相似文献   
17.
BackgroundHomologous recombination deficiency (HRD) is a phenotype that is characterized by the inability of a cell to effectively repair DNA double-strand breaks using the homologous recombination repair (HRR) pathway. Loss-of-function genes involved in this pathway can sensitize tumors to poly(adenosine diphosphate [ADP]-ribose) polymerase (PARP) inhibitors and platinum-based chemotherapy, which target the destruction of cancer cells by working in concert with HRD through synthetic lethality. However, to identify patients with these tumors, it is vital to understand how to best measure homologous repair (HR) status and to characterize the level of alignment in these measurements across different diagnostic platforms. A key current challenge is that there is no standardized method to define, measure, and report HR status using diagnostics in the clinical setting.MethodsFriends of Cancer Research convened a consortium of project partners from key healthcare sectors to address concerns about the lack of consistency in the way HRD is defined and methods for measuring HR status.ResultsThis publication provides findings from the group’s discussions that identified opportunities to align the definition of HRD and the parameters that contribute to the determination of HR status. The consortium proposed recommendations and best practices to benefit the broader cancer community.ConclusionOverall, this publication provides additional perspectives for scientist, physician, laboratory, and patient communities to contextualize the definition of HRD and various platforms that are used to measure HRD in tumors.  相似文献   
18.
We report a case of pulmonary zygomycosis associated with unusual deposition of calcium salt crystals. The patient was a 75-year-old female who had onset of cough and shortness of breath. She was treated for community-acquired pneumonia but died despite intensive therapy. Postmortem examination revealed diffuse alveolar damage and multifocal necrotizing pneumonia associated with herpes simplex infection and invasive zygomycosis. Birefringent particles were seen associated with fungal elements in the lung parenchyma, within bronchial cartilage, and in blood vessel walls. By infrared spectroscopy, the birefringent particles in the pulmonary parenchyma and within bronchial cartilage had spectral characteristics of calcium oxalate dihydrate and calcium oxalate monohydrate, respectively. The birefringent crystals within vascular walls were identified as calcium carbonate. This case documents the chemical composition and location of 3 different calcium salt crystals in pulmonary zygomycosis. It also shows that among pulmonary fungal infections, calcium oxalate deposition is not restricted to aspergillosis.  相似文献   
19.
Background: Whether psychological resilience correlates with neurocognitive performance is largely unknown. Therefore, we assessed association between neurocognitive performance and resilience in individuals with a history of childhood abuse or trauma exposure. Methods: In this cross‐sectional study of 226 highly traumatized civilians, we assessed neurocognitive performance, history of childhood abuse and other trauma exposure, and current depressive and PTSD symptoms. Resilience was defined as having ≥1 trauma and no current depressive or PTSD symptoms; non‐resilience as having ≥1 trauma and current moderate/severe depressive or PTSD symptoms. Results: The non‐resilient group had a higher percentage of unemployment (P=.006) and previous suicide attempts (P<.0001) than the resilient group. Both groups had comparable education and performance on verbal reasoning, nonverbal reasoning, and verbal memory. However, the resilient group performed better on nonverbal memory (P=.016) with an effect size of .35. Additionally, more severe childhood abuse or other trauma exposure was significantly associated with non‐resilience. Better nonverbal memory was significantly associated with resilience even after adjusting for severity of childhood abuse, other trauma exposure, sex, and race using multiple logistic regression (adjusted OR=1.2; P=.017). Conclusions: We examined resilience as absence of psychopathology despite trauma exposure in a highly traumatized, low socioeconomic, urban population. Resilience was significantly associated with better nonverbal memory, a measure of ability to code, store, and visually recognize concrete and abstract pictorial stimuli. Nonverbal memory may be a proxy for emotional learning, which is often dysregulated in stress‐related psychopathology, and may contribute to our understanding of resilience. Depression and Anxiety, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
20.
Childhood maltreatment increases risk for Posttraumatic Stress Disorder (PTSD). Maladaptive patterns of attention to emotionally salient stimuli warrant examination as possible mediators of the relationship between childhood maltreatment and PTSD. It remains unclear whether persistent attentional biases are differentially apparent in adults who were maltreated as children and either did or did not develop later PTSD symptomatology. The present study examined associations among attention bias, childhood maltreatment, and PTSD in adults. We tested the hypothesis that attentional bias for emotional cues (angry faces, happy faces), measured using the Dot Probe Task, would significantly mediate associations between childhood maltreatment and adult PTSD symptoms in a sample of 161 adults with and without childhood maltreatment histories and/or current PTSD symptoms. We found that attention bias toward happy faces partially mediated the relationship between childhood maltreatment and PTSD avoidance and numbing symptoms.  相似文献   
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