There are 6 clinical trials
This study will create a database of clinical and biological research for use in future studies, with information obtained from lung transplant recipients. The database will consist of genetic material and clinical outcomes to be used in future genotyping studies, that is, studies regarding the genetic makeup of individuals. Lung transplantation has become an important option for patients with advanced lung disease. More than 10,000 patients have received them to date, and about 1,200 transplant operations are performed worldwide each year. Although short-term survival has continued to improve, the 5-year survival rate is less than 50 percent. Most post transplant deaths are directly or directly caused by chronic lung rejection, a condition of scarring that worsens lung function. Patients evaluated for lung transplants at Duke University Medical Center may be eligible for this study. For developing the database, a small amount of blood, about 3 tablespoons, will be collected from patients. Blood collection for the research will be done at the same time as blood is drawn for necessary tests. The blood cells and DNA (which contains genetic material) will be isolated for analysis. Patients' DNA samples collected will be identified by a code, and all other identifying information will be removed. Patients may be asked to donate additional blood samples after their lung transplant if researchers would like to reexamine their blood. This study will not have a direct benefit for participants. However, during the study, if it is found that any patients have an inherited risk for a disease likely to cause early death if the disease is not treated, then the researchers will attempt to notify those patients. Overall, it is hoped that information gained during this study will help medical professionals to learn more about immune activation and to see how the reactivity of lung transplant patients changes over time. If specific genetic risks could be identified, it might lead to individualized treatments that work on the immune system. Short-term and long-term survival of lung transplant recipients may thus be improved.
We recently completed a study that demonstrated two single nucleotide polymorphisms (SNPs) Asp299Gly and Thr399Ile (polymorphisms of the human Toll 4 gene associated with endotoxin hyporesponsiveness) were associated with decreased acute rejection after lung transplantation. --- Asp299Gly ---
The purpose of the study is to determine the role of nitric oxide (NO) in asthma and to characterize the symptoms associated with inhaled endotoxin (lipopolysaccharide [LPS]) in normal subjects. In this study, we will determine the effect of inhaled endotoxin on exhaled NO in healthy African Americans, with and without NOS2 promoter polymorphisms. The protocol described in this submission will involve the use of NIH Clinical Center Reference Endotoxin which has been approved by the FDA under IND BB-IND-10035.
Because SNPs in the TLR4 gene result in a lack of airway obstruction in response to endotoxin, we will genotype the 1000 DNA samples for the Asp299Gly and Thr399Ile TLR4 polymorphisms in Phase 1 and exclude these individuals from the studies proposed in Phase 2. Likewise, CD14 serves as a coreceptor for endotoxin and polymorphisms in the CD14 gene and promoter have been associated with asthma and responsiveness to endotoxin. --- Asp299Gly ---
The overall goal of this project is to identify genes that are involved in the development of airflow obstruction and airway inflammation in asthmatics, and to determine whether polymorphisms in these differentially expressed genes predispose individuals to develop asthma. In this project, we hypothesize that polymorphisms of genes expressed by the airway epithelia in asthmatics following specific airway challenges predispose individuals to the development of asthma.
We hypothesize that individuals with the co-segregating Asp299Gly and Thr399Ile mutations in the TLR4 gene will exhibit a defective immune response to LPS, and that specific components of altered immunity in these individuals are linked to characteristic airway responses to LPS. Specific Aim 1: Approximately 1000 individuals will be genotyped in order to establish 3 study groups: 10 subjects homozygous for the TLR4 299/399 mutation; 10 subjects heterozygous for the TLR4 299/399 mutation; and 10 subjects homozygous for wild type TLR 4. Specific Aim 2: Ten individuals with wild type TLR4, 10 individuals heterozygous for mutant TLR4 and 10 individuals homozygous for mutant TLR4 will be phenotyped for airway responsiveness to inhaled LPS. --- Asp299Gly ---
The purpose of this study is to determine if sequence variations in genes involved in the development and function of vulnerable organs increases susceptibility to chronic lung disease (CLD) and other diseases affecting premature infants, such as necrotizing enterocolitis (NEC), sepsis, patent ductus arteriosus (PDA) and intraventricular hemorrhage (IVH). The study will also determine whether measurement of certain biomarkers in serum will identify infants who will develop these complications of prematurity. Previous studies from this institution and others have identified genetic variants in some genes, such as toll like receptor genes are associated with higher risk of CLD or NEC. The interaction of these variants with other gene variants that can influence the risk of these diseases remains unclear.
Our hypothesis will be tested in VLBW infants in four specific aims: (1) To determine whether the presence of previously described single nucleotide polymorphisms (SNPs) in TLR4 (Asp299Gly, Thr399Ile) TLR2 (Arg753Gln) and TLR5 (Arg392STOP) genes is associated with an increased risk of CLD ; (2) to detect by DNA sequencing if novel genetic variations in TLR4, TLR2, TLR9, MyD88 and other innate immune genes increases the risk of CLD or other disease in premature infants; (3) to identify by gene sequence approach whether variants in other repair and growth genes alter susceptibility to diseases affecting premature infants such as CLD,NEC or sepsis or PDA or IVH; and (4) whether alterations in cytokines, miRNA and other biomarker levels in serum from the same blood samples can provide additional predictive value in recognizing the risk of diseases of prematurity. --- Asp299Gly ---
The TLR4 (Asp299Gly, Thr399Ile) TLR2 (Arg753Gln) and TLR5 (Arg392STOP) SNPs will be evaluated using a multiplex Single Base extension based technique, using commercially available primers. --- Asp299Gly ---
Purpose So far anatomical abnormalities (mostly congenital) were, in the majority of the patients, associated with urinary track infections. In this study the researchers will try to investigate the role of TLRs as molecular interactions between bacterial virulence and host response. TLRs are important mediators in the development of the natural immunity against bacteria. They recognize microbial pathogen associated molecular patterns and alert the host's immune system to the presence of invading microbes
The Role of TLR-4 Asp299Gly and Thr399Ile Polymorphisms in Children With Urinary Tack Infections. --- Asp299Gly ---
2. evaluate the effect of the TLR-gene Asp299Gly and Thr399Ile polymorphisms on the development and clinical severity of urinary tract infections (UTI) in children. --- Asp299Gly ---
Toll-like receptors (TLRs) play a key role in the innate immune system. Toll-like receptor-4 (TLR4) in particular, appears to play a role in susceptibility to cancer. Of 44 identified SNPs (small nucleotide polymorphisms) in TLR4, the most common is an A-G substitution at nucleotide position +896, downstream of the cDNA start codon, a missense mutation which leads to an amino acid substitution Asp299Gly in the third exon of the TLR4 gene. Pre-clinical studies from our laboratory have shown an association of TLR4 with ultraviolet radiation induced skin cancer. Hence, in this study we will assess the pattern of TLR4 polymorphisms and susceptibility to skin cancer.
Of 44 identified SNPs (small nucleotide polymorphisms) in TLR4, the most common is an A-G substitution at nucleotide position +896, downstream of the cDNA start codon, a missense mutation which leads to an amino acid substitution Asp299Gly in the third exon of the TLR4 gene. --- Asp299Gly ---
TLR4 SNP Asp299Gly. --- Asp299Gly ---
Description: TLR4 SNP Asp299Gly
Measure: single nucleotide polymorphism Time: once during the course of study