148 research outputs found
Development of new all-optical signal regeneration technique
All-optical signal regeneration have been the active research area since last decade due to evolution of nonlinear optical signal processing. Existing all-optical signal regeneration techniques are agitated in producing low Bit Error Rate (BER) of 10-10 at below than -10 dBm power received. In this paper, a new all-optical signal regeneration technique is developed by using phase sensitive amplification and designed optical phase locked signal mechanism. The developed all-optical signal regeneration technique is tested for different 10 Gb/s Differential Phase Shift Keying degraded signals. It is determined that the designed all-optical signal regeneration technique is able to provide signal regeneration with noise mitigation for degraded signals. It is analyzed that overall, for all degraded test signals, average BER of 10-13 is achieved at received power of -14 dBm. The designed technique will be helpful to enhance the performance of existing signal regeneration systems in the presence of severe noise by providing minimum BER at low received power
Phosphine-Catalyzed Formation of Carbon-Sulfur Bonds: Catalytic Asymmetric Synthesis of gamma-Thioesters
Supporting Information Available: Experimental procedures and compound characterization data. This material is available free of charge via the Internet at http://pubs.acs.org.A method for catalytic asymmetric γ sulfenylation of carbonyl compounds has been developed. In the presence of an appropriate catalyst, thiols not only add to the γ position of allenoates, overcoming their propensity to add to the β position in the absence of a catalyst, but do so with very good enantioselectivity. Sulfur nucleophiles are now added to the three families of nucleophiles (carbon, nitrogen, and oxygen) that had earlier been shown to participate in catalyzed γ additions. The phosphine catalyst of choice, TangPhos, had previously only been employed as a chiral ligand for transition metals, not as an efficient enantioselective nucleophilic catalyst.National Institutes of Health (U.S.)National Institute of General Medical Sciences (U.S.) (R01-GM57034)Merck & Co.Novartis (Firm
Circulating endothelial cell count: a reliable marker of endothelial damage in patients undergoing hematopoietic stem cell transplantation
The physio-pathologic interrelationships between endothelium and GvHD have been better elucidated and have led to definition of the entity 'endothelial GvHD' as an essential early phase prior to the clinical presentation of acute GvHD. Using the CellSearch system, we analyzed circulating endothelial cells (CEC) in 90 allogeneic hematopoietic stem cell transplantation (allo-HSCT) patients at the following time-points: T1 (pre-conditioning), T2 (pre-transplant), T3 (engraftment), T4 (onset of GvHD) and T5 (1 week after steroid treatment). Although CEC changes in allo-HSCT represent a dynamic phenomenon influenced by many variables (that is, conditioning, immunosuppressive treatments, engraftment syndrome and infections), we showed that CEC peaks were constantly seen at onset of acute GvHD and invariably returned to pre-transplant values after treatment response. Since we showed that CEC changes during allo-HSCT has rapid kinetics that may be easily missed if blood samples are drawn at pre-fixed time-points, we rather suggest an 'on demand' evaluation of CEC counts right at onset of GvHD clinical symptoms to possibly help differentiate GvHD from other non-endothelial complications. We confirm that CEC changes are a suitable biomarker to monitor endothelial damage in patients undergoing allo-transplantation and hold the potential to become a useful tool to support GvHD diagnosis (ClinicalTrials.gov NCT02064972).Bone Marrow Transplantation advance online publication, 11 September 2017; doi:10.1038/bmt.2017.194
Assessing Perceived Risk and STI Prevention Behavior: A National Population-Based Study with Special Reference to HPV
Aim: This thesis aims to provide a multidimensional assessment of infection risks and
to evaluate strategies for HPV prevention including vaccination with quadrivalent HPVvaccines,
dose-level vaccine effectiveness and condom use in high STI risk situations.
Methods: Multiple population-based registers and questionnaire responses provided data
for this thesis. Various multivariable and univariate regression models were fit.
Findings: Overall, quadrivalent HPV-vaccination was highly effective against genital
warts (GW) also referred to as condyloma, which is the first HPV disease endpoint
possible to measure. However, effectiveness was contingent upon young age-at-first
vaccination, with effectiveness declining steadily the older the age-at-first vaccination.
Among women above 20 years of age there was low to immeasurable effectiveness and
suggestive evidence vaccinations in this age group tended to reach women at high GW
risk. There were marked socioeconomic disparities in the opportunistic (on-demand with
co-pay) vaccination strategy evaluated, with women and girls who have parents with
the highest education level compared to the lowest having a 15 times greater likelihood
to be vaccinated (Study III). Once vaccination was initiated, however, high parental
education level was unrelated to vaccination completion. Maximum protection against
GW was found among girls vaccinated under the age of 17 who had received three doses
of the vaccine. No differences in effectiveness were found for girls who received twodoses
between ages 10-16 with that of those who received three-doses between ages 17-
19 (Study IV). GW affects more men than women in Sweden as of 2010 with 453 per
100 000 men and 365 per 100 000 women treated. A decline between 25-30% was seen
between 2006 and 2010 among women in the age groups with the highest vaccination
coverage. No decline was found amongst men and their GW incidence has steadily
increased between 2006 and 2010 (Study II). Reported condom use in high risk situations
was low among both men and women, with 41% of men and 34% of women reporting
always/almost always condom use with temporary partners. STI risk perception was also
low, with approximately 10% of sexually active respondents considering themselves at
large risk of contracting an STI. There was no association between men’s condom use and
their STI risk perception but there was an association for women (Study I).
Conclusions: Results suggest that males bear a substantial burden of HPV-related
condyloma where incidence has dropped among women. When planning HPVvaccination
among females, efforts should target girls under age 14 for maximum
effectiveness. Quadrivalent HPV-vaccination offers most protection against condyloma at
three doses. Gross social inequity was found with opportunistic HPV-vaccination. There
were large gender differences in factors associated with condom use in high risk situations
and STI risk perceptions
ACE (I/D) polymorphism and response to treatment in coronary artery disease: a comprehensive database and meta-analysis involving study quality evaluation
<p>Abstract</p> <p>Background</p> <p>The role of angiotensin-converting enzyme (<it>ACE</it>) gene insertion/deletion (<it>I/D</it>) polymorphism in modifying the response to treatment modalities in coronary artery disease is controversial.</p> <p>Methods</p> <p>PubMed was searched and a database of 58 studies with detailed information regarding <it>ACE I/D </it>polymorphism and response to treatment in coronary artery disease was created. Eligible studies were synthesized using meta-analysis methods, including cumulative meta-analysis. Heterogeneity and study quality issues were explored.</p> <p>Results</p> <p>Forty studies involved invasive treatments (coronary angioplasty or coronary artery by-pass grafting) and 18 used conservative treatment options (including anti-hypertensive drugs, lipid lowering therapy and cardiac rehabilitation procedures). Clinical outcomes were investigated by 11 studies, while 47 studies focused on surrogate endpoints. The most studied outcome was the restenosis following coronary angioplasty (34 studies). Heterogeneity among studies (p < 0.01) was revealed and the risk of restenosis following balloon angioplasty was significant under an additive model: the random effects odds ratio was 1.42 (95% confidence interval:1.07–1.91). Cumulative meta-analysis showed a trend of association as information accumulates. The results were affected by population origin and study quality criteria. The meta-analyses for the risk of restenosis following stent angioplasty or after angioplasty and treatment with angiotensin-converting enzyme inhibitors produced non-significant results. The allele contrast random effects odds ratios with the 95% confidence intervals were 1.04(0.92–1.16) and 1.10(0.81–1.48), respectively. Regarding the effect of <it>ACE I/D </it>polymorphism on the response to treatment for the rest outcomes (coronary events, endothelial dysfunction, left ventricular remodeling, progression/regression of atherosclerosis), individual studies showed significance; however, results were discrepant and inconsistent.</p> <p>Conclusion</p> <p>In view of available evidence, genetic testing of <it>ACE I/D </it>polymorphism prior to clinical decision making is not currently justified. The relation between <it>ACE </it>genetic variation and response to treatment in CAD remains an unresolved issue. The results of long-term and properly designed prospective studies hold the promise for pharmacogenetically tailored therapy in CAD.</p
Dendritic cell vaccines containing lymphocytes produce improved immunogenicity in patients with cancer
Genetic effects on gene expression across human tissues
Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression levels across individuals and diverse tissues of the human body, many of which are not easily accessible. Here we describe genetic effects on gene expression levels across 44 human tissues. We find that local genetic variation affects gene expression levels for the majority of genes, and we further identify inter-chromosomal genetic effects for 93 genes and 112 loci. On the basis of the identified genetic effects, we characterize patterns of tissue specificity, compare local and distal effects, and evaluate the functional properties of the genetic effects. We also demonstrate that multi-tissue, multi-individual data can be used to identify genes and pathways affected by human disease-associated variation, enabling a mechanistic interpretation of gene regulation and the genetic basis of diseas
Microglial brain region−dependent diversity and selective regional sensitivities to aging
Microglia play critical roles in neural development, homeostasis and neuroinflammation and are increasingly implicated in age-related neurological dysfunction. Neurodegeneration often occurs in disease-specific spatially-restricted patterns, the origins of which are unknown. We performed the first genome-wide analysis of microglia from discrete brain regions across the adult lifespan of the mouse and reveal that microglia have distinct region-dependent transcriptional identities and age in a regionally variable manner. In the young adult brain, differences in bioenergetic and immunoregulatory pathways were the major sources of heterogeneity and suggested that cerebellar and hippocampal microglia exist in a more immune vigilant state. Immune function correlated with regional transcriptional patterns. Augmentation of the distinct cerebellar immunophenotype and a contrasting loss in distinction of the hippocampal phenotype among forebrain regions were key features during ageing. Microglial diversity may enable regionally localised homeostatic functions but could also underlie region-specific sensitivities to microglial dysregulation and involvement in age-related neurodegeneration
Catalytic Asymmetric 1,6-Michael Addition of Arylthiols to 3-Methyl-4-nitro-5-alkenyl-isoxazoles with Bifunctional Catalysts
Genetic effects on gene expression across human tissues
Characterization of the molecular function of the human genome and its variation across individuals is essential for identifying the cellular mechanisms that underlie human genetic traits and diseases. The Genotype-Tissue Expression (GTEx) project aims to characterize variation in gene expression levels across individuals and diverse tissues of the human body, many of which are not easily accessible. Here we describe genetic effects on gene expression levels across 44 human tissues. We find that local genetic variation affects gene expression levels for the majority of genes, and we further identify inter-chromosomal genetic effects for 93 genes and 112 loci. On the basis of the identified genetic effects, we characterize patterns of tissue specificity, compare local and distal effects, and evaluate the functional properties of the genetic effects. We also demonstrate that multi-tissue, multi-individual data can be used to identify genes and pathways affected by human disease-associated variation, enabling a mechanistic interpretation of gene regulation and the genetic basis of disease
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