49 research outputs found
Exploring pharmacodynamics of immunosuppresive agents in transplantation
Supported by advancements in technology, surgical techniques and
immunosuppressive drugs, solid organ transplantation has become the
preferred solution to end stage organ failure. The first solid organ
transplantation was performed in 1954 under supervision of Joseph Murray in
the Peter Bent Brigham Hospital in Boston. A kidney from a healthy donor was
transplanted into his identical twin, who suffered from chronic glomerulonephritis. The transplanted organ functioned immediately and the recipient
survived for 25 years while the donor lived for another 56 years. Since the twins
were genetically identical, no suppression of the immune system was needed.
Transplantation between individuals other than identical twins was
made possible a decade later by the use of the combination of azathioprine and
corticosteroids, achieving a 1 year allograft1 survival rate of 40 to 50 percent
Phospho-specific flow cytometry for pharmacodynamic monitoring of immunosuppressive therapy in transplantation
Organ transplant recipients frequently suffer from toxicity or from lack of efficacy of immunosuppressive drugs, which can be attributed to individual variations in drug sensitivity. This problem can be resolved by applying pharmacodynamic monitoring that focuses on measuring the biological effects of drugs. Here we discuss the new technique called phospho-specific flow cytometry to monitor the activity of intracellular immune signaling pathways at the single-cell level in whole blood samples. Through this tool the efficacy of immunosuppressive medication can be assessed, novel targets can be identified, and differences in drug sensitivity between cells and patients can be clarified
Breed and adaptive response modulate bovine peripheral blood cells’ transcriptome
Background: Adaptive response includes a variety of physiological modifications to face changes in external or internal conditions and adapt to a new situation. The acute phase proteins (APPs) are reactants synthesized against environmental stimuli like stress, infection, inflammation. Methods: To delineate the differences in molecular constituents of adaptive response to the environment we performed the whole-blood transcriptome analysis in Italian Holstein (IH) and Italian Simmental (IS) breeds. For this, 663 IH and IS cows from six commercial farms were clustered according to the blood level of APPs. Ten extreme individuals (five APP+ and APP- variants) from each farm were selected for the RNA-seq using the Illumina sequencing technology. Differentially expressed (DE) genes were analyzed using dynamic impact approach (DIA) and DAVID annotation clustering. Milk production data were statistically elaborated to assess the association of APP+ and APP- gene expression patterns with variations in milk parameters. Results: The overall de novo assembly of cDNA sequence data generated 13,665 genes expressed in bovine blood cells. Comparative genomic analysis revealed 1,152 DE genes in the comparison of all APP+ vs. all APP- variants; 531 and 217 DE genes specific for IH and IS comparison respectively. In all comparisons overexpressed genes were more represented than underexpressed ones. DAVID analysis revealed 369 DE genes across breeds, 173 and 73 DE genes in IH and IS comparison respectively. Among the most impacted pathways for both breeds were vitamin B6 metabolism, folate biosynthesis, nitrogen metabolism and linoleic acid metabolism. Conclusions: Both DIA and DAVID approaches produced a high number of significantly impacted genes and pathways with a narrow connection to adaptive response in cows with high level of blood APPs. A similar variation in gene expression and impacted pathways between APP+ and APP- variants was found between two studied breeds. Such similarity was also confirmed by annotation clustering of the DE genes. However, IH breed showed higher and more differentiated impacts compared to IS breed and such particular features in the IH adaptive response could be explained by its higher metabolic activity. Variations of milk production data were significantly associated with APP+ and APP- gene expression patterns
A normal genetic variation modulates synaptic MMP-9 protein levels and the severity of schizophrenia symptoms
Abstract Matrix metalloproteinase 9 (MMP‐9) has recently emerged as a molecule that contributes to pathological synaptic plasticity in schizophrenia, but explanation of the underlying mechanisms has been missing. In the present study, we performed a phenotype‐based genetic association study (PGAS) in > 1,000 schizophrenia patients from the Göttingen Research Association for Schizophrenia (GRAS) data collection and found an association between the MMP‐9 rs20544 C/T single‐nucleotide polymorphism (SNP) located in the 3′untranslated region (UTR) and the severity of a chronic delusional syndrome. In cultured neurons, the rs20544 SNP influenced synaptic MMP‐9 activity and the morphology of dendritic spines. We demonstrated that Fragile X mental retardation protein (FMRP) bound the MMP‐9 3′UTR. We also found dramatic changes in RNA structure folding and alterations in the affinity of FMRP for MMP‐9 RNA, depending on the SNP variant. Finally, we observed greater sensitivity to psychosis‐related locomotor hyperactivity in Mmp‐9 heterozygous mice. We propose a novel mechanism that involves MMP‐9‐dependent changes in dendritic spine morphology and the pathophysiology of schizophrenia, providing the first mechanistic insights into the way in which the single base change in the MMP‐9 gene (rs20544) influences gene function and results in phenotypic changes observed in schizophrenia patients
Postnatal LPS Challenge Impacts Escape Learning and Expression of Plasticity Factors Mmp9 and Timp1 in Rats: Effects of Repeated Training
Bacterial intoxication associated with inflammatory conditions during development can impair brain functions, in particular evolutionarily novel forms of memory, such as explicit learning. Little is known about the dangers of early-life inflammation on more basic forms of learning, for example, the acquisition of motor escape abilities, which are generally better preserved under pathological conditions. To address this limitation in knowledge, an inflammatory response was elicited in Wistar pups by lipopolysaccharide (LPS) injections (25 mu g/kg) on postnatal days P15, P18 and P21. The acquisition of escape behaviour was tested from P77 by active avoidance footshock model and water maze. Open-field behaviour and blood corticosterone levels were also measured. Rat brain tissue was collected from pups 2 h post-injection and from adult rats which either underwent escape training on P77-P81 or remained untrained. mRNA levels of developmental brain plasticity factors MMP-9 and TIMP-1 were investigated in the medial prefrontal cortex and ventral/dorsal hippocampus. LPS-challenged rats displayed moderately deficient escape responses in both memory tests, increased freezing behaviour and, surprisingly, reduced blood cortisol levels. Mmp9 and Timp1, and their ratio to one another, were differentially altered in pups versus adult untrained rats but remained unchanged overall in rats trained in either learning task. Together, our data indicate that systemic pro-inflammatory response during early postnatal development has long-lasting effects, including on the acquisition of motor escape abilities and plasticity factor expression, into adulthood. Our data suggest that altered stress response could possibly mediate these deviations and repeated training might generate positive effects on plasticity under the employed conditions
Investigation of pile-integrity using novel signal processing methods
As there are a lot of limitations on health monitoring of piles, stress wave propagation tests are of interest among civil engineers and researchers. In these methods, the testing signal recorded by receiver on the pile head should be analyzed to check whether any defect exists. In this paper, the application of low strain pile-integrity tests and interpretation of the results by Continuous wavelet transform (CWT) is studied. Finite element model of some imaginary piles are provided in order to analyze the response of the structures due to a known signal. The results demonstrate that the testing signal can be broken down into time and frequency domain at the same time. As a result, more characteristics of the testing signal can be depicted, and defects can be detected easier than the traditional signal processing methods, such as Fourier transform (FT). Furthermore, the results show that impedance is not a proper criterion to identify damage severity, and damage detection ability of low strain test is a function of defect length as well
Investigation of pile-integrity using novel signal processing methods
As there are a lot of limitations on health monitoring of piles, stress wave propagation tests are of interest among civil engineers and researchers. In these methods, the testing signal recorded by receiver on the pile head should be analyzed to check whether any defect exists. In this paper, the application of low strain pile-integrity tests and interpretation of the results by Continuous wavelet transform (CWT) is studied. Finite element model of some imaginary piles are provided in order to analyze the response of the structures due to a known signal. The results demonstrate that the testing signal can be broken down into time and frequency domain at the same time. As a result, more characteristics of the testing signal can be depicted, and defects can be detected easier than the traditional signal processing methods, such as Fourier transform (FT). Furthermore, the results show that impedance is not a proper criterion to identify damage severity, and damage detection ability of low strain test is a function of defect length as well
