59 research outputs found
Perturbation of the yeast N-acetyltransferase NatB induces elevation of protein phosphorylation levels
<p>Abstract</p> <p>Background</p> <p>The addition of an acetyl group to protein N-termini is a widespread co-translational modification. NatB is one of the main N-acetyltransferases that targets a subset of proteins possessing an N-terminal methionine, but so far only a handful of substrates have been reported. Using a yeast <it>nat3Δ </it>strain, deficient for the catalytic subunit of NatB, we employed a quantitative proteomics strategy to identify NatB substrates and to characterize downstream effects in <it>nat3Δ</it>.</p> <p>Results</p> <p>Comparing by proteomics WT and <it>nat3Δ </it>strains, using metabolic <sup>15</sup>N isotope labeling, we confidently identified 59 NatB substrates, out of a total of 756 detected acetylated protein N-termini. We acquired in-depth proteome wide measurements of expression levels of about 2580 proteins. Most remarkably, NatB deletion led to a very significant change in protein phosphorylation.</p> <p>Conclusions</p> <p>Protein expression levels change only marginally in between WT and <it>nat3Δ</it>. A comparison of the detected NatB substrates with their orthologous revealed remarkably little conservation throughout the phylogenetic tree. We further present evidence of post-translational N-acetylation on protein variants at non-annotated N-termini. Moreover, analysis of downstream effects in <it>nat3Δ </it>revealed elevated protein phosphorylation levels whereby the kinase Snf1p is likely a key element in this process.</p
p53 and ovarian carcinoma survival: an Ovarian Tumor Tissue Analysis consortium study
Our objective was to test whether p53 expression status is associated with survival for women diagnosed with the most common ovarian carcinoma histotypes (high-grade serous carcinoma [HGSC], endometrioid carcinoma [EC], and clear cell carcinoma [CCC]) using a large multi-institutional cohort from the Ovarian Tumor Tissue Analysis (OTTA) consortium. p53 expression was assessed on 6,678 cases represented on tissue microarrays from 25 participating OTTA study sites using a previously validated immunohistochemical (IHC) assay as a surrogate for the presence and functional effect of TP53 mutations. Three abnormal expression patterns (overexpression, complete absence, and cytoplasmic) and the normal (wild type) pattern were recorded. Survival analyses were performed by histotype. The frequency of abnormal p53 expression was 93.4% (4,630/4,957) in HGSC compared to 11.9% (116/973) in EC and 11.5% (86/748) in CCC. In HGSC, there were no differences in overall survival across the abnormal p53 expression patterns. However, in EC and CCC, abnormal p53 expression was associated with an increased risk of death for women diagnosed with EC in multivariate analysis compared to normal p53 as the reference (hazard ratio [HR] = 2.18, 95% confidence interval [CI] 1.36-3.47, p = 0.0011) and with CCC (HR = 1.57, 95% CI 1.11-2.22, p = 0.012). Abnormal p53 was also associated with shorter overall survival in The International Federation of Gynecology and Obstetrics stage I/II EC and CCC. Our study provides further evidence that functional groups of TP53 mutations assessed by abnormal surrogate p53 IHC patterns are not associated with survival in HGSC. In contrast, we validate that abnormal p53 IHC is a strong independent prognostic marker for EC and demonstrate for the first time an independent prognostic association of abnormal p53 IHC with overall survival in patients with CCC
31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two
Background
The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd.
Methods
We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background.
Results
First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001).
Conclusions
In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival
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Novel Treatments for Chronic Ocular Surface Pain
Several etiologies can contribute to ocular surface pain including nociceptive, peripheral neuropathic, and central neuropathic mechanisms. Clinical clues can help identify contributors to ocular surface pain in a patient. In individuals whose pain persists despite targeting nociceptive contributors, neuropathic mechanisms should be considered and addressed using oral, topical, and/or adjuvant agents
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Eusol-C as Corneal Cold Storage Solution: Early Clinical Outcomes of Keratoplasty
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Molecular Imaging for Estrogen Receptor-Positive Breast Cancer Clinical Applications of Whole Body and Dedicated Breast Positron Emission Tomography
18F-fluoroestradiol (18F-FES) is a Food and Drug Administration-approved radiopharmaceutical used for molecular imaging of the estrogen receptor (ER). When combined with PET, 18F-FES may improve the diagnosis of ER-positive breast cancer in the metastatic setting and provide insights into tumor heterogeneity. In this article, we review data on the use of 18F-FES imaging for treatment selection, staging, imaging lobular breast cancer, and the novel breast specific imaging tool, dedicated breast PET
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Outcomes of Secondary Intraocular Lens Implantation and Descemet Stripping Endothelial Keratoplasty-Comparing Staged Versus Combined Surgical Approach
The aim of this study was to compare the outcomes of staged versus combined surgical approach for secondary intraocular lens (IOL) implantation and Descemet stripping endothelial keratoplasty (DSEK).
This is a retrospective review of 124 eyes from 124 patients who underwent either staged or combined secondary IOL implantation in addition to DSEK over a 5-year period at 2 academic tertiary referral centers, between January 1, 2014, and October 1, 2019. Corrected distance visual acuity (CDVA), presence of graft detachment, primary graft failure (PGF), and cystoid macular edema were documented and analyzed.
The CDVA for the 1- to 2- month follow-up period was significantly better in the staged group compared with the combined group ( P = 0.011). By the postoperative 6- to 9-month follow-up period, there was no significant difference in the CDVA between the groups ( P = 0.591). There was no significant difference in the incidence of PGF or graft detachment between the 2 groups ( P > 0.05). In addition, there was no significant difference in the CDVA or rate of postoperative complications between the different methods of IOL fixation.
The short-term visual outcomes were significantly better in eyes that underwent staged secondary IOL implantation and DSEK versus the combined surgical approach, although the difference was no longer present at 6 to 9 months. There was no difference in the rate of PGF or graft detachment between the 2 groups
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Utilization of Online Resources by Patients in an Ophthalmic Emergency Department
Abstract
Objective
To describe the utilization of online resources by patients prior to presentation to an ophthalmic emergency department (ED) and to assess the accuracy of online resources for ophthalmic diagnoses.
Methods
This is a prospective survey of patients presenting to an ophthalmic ED for initial evaluation of ocular symptoms. Prior to evaluation, patients completed surveys assessing ocular symptoms, Internet usage, and presumed self-diagnoses. Demographics and characteristics of Internet usage were determined. Accuracy of self-diagnoses was compared between Internet users and nonusers. Diagnoses were classified as high or low acuity based on agreement between senior authors.
Results
A total of 144 patients completed surveys. Mean (standard deviation) age was 53.2 years (18.0). One-third of patients used the Internet for health-related searches prior to presentation. Internet users were younger compared with nonusers (48.2 years [16.5] vs. 55.5 years [18.3],
p
= 0.02). There were no differences in sex, ethnicity, or race. Overall, there was a threefold difference in proportion of patients correctly predicting their diagnoses, with Internet users correctly predicting their diagnoses more often than nonusers (41 vs. 13%,
p
< 0.001). When excluding cases of known trauma, the difference in proportion increased to fivefold (Internet users 40% vs. nonusers 8%,
p
< 0.001). Upon classification by acuity level, Internet users demonstrated greater accuracy than nonusers for both high- (42 vs. 17%,
p
= 0.03) and low (41 vs. 10%,
p
= 0.001)-acuity diagnoses. Greatest accuracy was in cases of external lid conditions such as chalazia and hordeola (100% [4/4] of Internet users vs. 40% (2/5) of nonusers), conjunctivitis (43% [3/7] of Internet users vs. 25% [2/8] of nonusers), and retinal traction or detachments (57% [4/7] of Internet users vs. 0% [0/4] of nonusers). The most frequently visited Web sites were Google (82%) and WebMD (40%). Patient accuracy did not change according to the number of Web sites visited, but patients who visited the Mayo Clinic Web site had greater accuracy compared with those who visited other Web sites (89 vs. 30%,
p
= 0.003).
Conclusion
Patients with ocular symptoms may seek medical information on the Internet before evaluation by a physician in an ophthalmic ED. Online resources may improve the accuracy of patient self-diagnosis for low- and high-acuity diagnoses
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Case-Control Study Examining the Composition of the Gut Microbiome in Individuals With and Without Immune-Mediated Dry Eye
Gut microbiome alterations have been associated with various autoimmune diseases. There are limited data, however, on relationships between gut dysbiosis and immune-related dry eye (DE). Our aim was to compare the gut microbiome composition of individuals with early and late markers of Sjögren syndrome (SS) with controls without DE.We compared 20 individuals with positive early markers [antisalivary protein 1 (SP1), antiparotid secretory protein (PSP), anticarbonic anhydrase 6 (CA6) IgG, IgA, and IgM, n = 19)], or late markers (anti-Ro/SS-A and anti-La/SS-B, n = 1) of SS with no comorbid autoimmune diagnoses and 20 age-matched and sex-matched controls. Collected stool samples underwent deep RNA sequencing. The main outcomes measured included gut microbiome composition and diversity.A total of 20 cases [Dry Eye Questionnaire-5 15.2 ± 3.4, Ocular Surface Disease Index 55.1 ± 22.8, and Schirmer 7.1 ± 5.2 mm] were compared with 20 controls (Dry Eye Questionnaire-5 4.8 ± 3.8, Ocular Surface Disease Index 14.2 ± 12.3, and Schirmer 20.4 ± 9.2 mm). No differences were observed in α-diversity (P = 0.97) or overall community structure (P = 0.62). Between groups, 32 species were differentially abundant (P < 0.01). Among cases, 27 were relatively more abundant, including 10 Lactobacillus and 4 Bifidobacterium species. A relative depletion of 5 species was found in cases compared with controls, notably Fusobacterium varium and Prevotella stercorea.Differences in gut microbiome composition were found in individuals with mostly early markers of SS compared with controls. However, their clinical significance to DE manifestations remains unclear. Further studies are needed to elucidate the role of gut dysbiosis on immune dysregulation and disease activity in the various forms of immune-mediated DE
Crystal structure of the anti-viral APOBEC3G catalytic domain and functional implications
Projekti i njihovo kvalitetno upravljanje poprimaju sve važniju ulogu u organizacijama svih veličina i grana industrije. Zbog sve bržih procesa i složenosti poslovnih sustava, poduzeća su primorana odmaknuti se od tradicionalnih metoda vođenja projekata te se preusmjeriti na suvremene - agilne metode. U radu se prikazuju glavne odrednice tradicionalnih i suvremenih metoda vođenja projekata, razlike te prednosti i mane. S obzirom na sve veću popularnost agilnog pristupa, razvijen je velik broj alata za upravljanje projektima koristeći suvremene metode. Na kraju se predstavlja ciklus i način upravljanja projektom pri izradi mobilne aplikacije u alatu Jira primjenjujući SCRUM metod
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