498 resultados para Biology, Neuroscience|Health Sciences, Nursing


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Both angiogenesis and vasculogenesis contribute to the formation and expansion of tumor neovasculature. We demonstrated that bone marrow (BM)-derived cells migrated to TC71 Ewing's tumors and differentiated into endothelial cells lining perfused, functional tumor neovessels. In addition, a substantial fraction of recruited, BM-derived cells resided in the vessel vicinity but did not demonstrate endothelial differentiation. Rather, these perivascular cells expressed desmin and PDGFR-β, implying pericyte-like/vascular smooth muscle cell differentiation. No defined, consensus set of markers exists for endothelial progenitor cells (EPCs) and the specific subsets of BM cells that participate in vessel formation are poorly understood. We used a functional in vivo assay to investigate the roles performed by specific human- and murine-derived stem/progenitor subpopulations within Ewing's sarcoma tumors. CD34 +45+, CD34+38-, VEGFR2 + and Sca1+Gr1+ cells were demonstrated to establish residence within the expanding tumor vascular network and differentiate into endothelial cells and pericytes. By constrast, CD34-45 + and Sca1-Gr1+ cells predominantly localized to sites outside the Ewing's tumor vasculature, and differentiated into macrophages. Cytokines, such as VEGF, influence the recruitment of BM cells and their incorporation into the tumor vasculature. VEGF165-inhibited TC/siVEGF7-1 Ewing's tumors showed delayed in vivo tumor growth, decreased vessel density, and reduced infiltration of BM progenitor cells. We tested whether another chemoattractant, Stromal Cell-Derived Factor-1 (SDF-1), could augment the growth of these VEGF165-inhibited TC/siVEGF 7-1 tumors by enhancing the recruitment of BM cells and stimulating neovasculature expansion. SDF-1 promoted progenitor cell chemotaxis and retainment of BM-derived pericyte precursors in close association with functional, perfused tumor blood vessels. Treatment of TC/siVEGF7-1 tumors with adenovirus-SDF-1α resulted in augmented tumor size, enhanced pericyte coverage of tumor neovessels, remodeling of vascular endothelium into larger, functional structures, and upregulation of PDGF-BB, with no effect on VEGF165. Taken together, these findings suggest that the recruitment of BM stem/progenitor cells plays an important role in the growth of Ewing's tumors. ^

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Colorectal cancer is the forth most common diagnosed cancer in the United States. Every year about a hundred forty-seven thousand people will be diagnosed with colorectal cancer and fifty-six thousand people lose their lives due to this disease. Most of the hereditary nonpolyposis colorectal cancer (HNPCC) and 12% of the sporadic colorectal cancer show microsatellite instability. Colorectal cancer is a multistep progressive disease. It starts from a mutation in a normal colorectal cell and grows into a clone of cells that further accumulates mutations and finally develops into a malignant tumor. In terms of molecular evolution, the process of colorectal tumor progression represents the acquisition of sequential mutations. ^ Clinical studies use biomarkers such as microsatellite or single nucleotide polymorphisms (SNPs) to study mutation frequencies in colorectal cancer. Microsatellite data obtained from single genome equivalent PCR or small pool PCR can be used to infer tumor progression. Since tumor progression is similar to population evolution, we used an approach known as coalescent, which is well established in population genetics, to analyze this type of data. Coalescent theory has been known to infer the sample's evolutionary path through the analysis of microsatellite data. ^ The simulation results indicate that the constant population size pattern and the rapid tumor growth pattern have different genetic polymorphic patterns. The simulation results were compared with experimental data collected from HNPCC patients. The preliminary result shows the mutation rate in 6 HNPCC patients range from 0.001 to 0.01. The patients' polymorphic patterns are similar to the constant population size pattern which implies the tumor progression is through multilineage persistence instead of clonal sequential evolution. The results should be further verified using a larger dataset. ^

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Monte Carlo simulation has been conducted to investigate parameter estimation and hypothesis testing in some well known adaptive randomization procedures. The four urn models studied are Randomized Play-the-Winner (RPW), Randomized Pôlya Urn (RPU), Birth and Death Urn with Immigration (BDUI), and Drop-the-Loses Urn (DL). Two sequential estimation methods, the sequential maximum likelihood estimation (SMLE) and the doubly adaptive biased coin design (DABC), are simulated at three optimal allocation targets that minimize the expected number of failures under the assumption of constant variance of simple difference (RSIHR), relative risk (ORR), and odds ratio (OOR) respectively. Log likelihood ratio test and three Wald-type tests (simple difference, log of relative risk, log of odds ratio) are compared in different adaptive procedures. ^ Simulation results indicates that although RPW is slightly better in assigning more patients to the superior treatment, the DL method is considerably less variable and the test statistics have better normality. When compared with SMLE, DABC has slightly higher overall response rate with lower variance, but has larger bias and variance in parameter estimation. Additionally, the test statistics in SMLE have better normality and lower type I error rate, and the power of hypothesis testing is more comparable with the equal randomization. Usually, RSIHR has the highest power among the 3 optimal allocation ratios. However, the ORR allocation has better power and lower type I error rate when the log of relative risk is the test statistics. The number of expected failures in ORR is smaller than RSIHR. It is also shown that the simple difference of response rates has the worst normality among all 4 test statistics. The power of hypothesis test is always inflated when simple difference is used. On the other hand, the normality of the log likelihood ratio test statistics is robust against the change of adaptive randomization procedures. ^

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Adenylyl cyclase (AC) converts ATP into cAMP, which activates protein kinase A (PKA). Activation of PKA leads to the phosphorylation of specific substrates. The mechanism of specificity of PKA phosphorylation baffled researchers for many years. The discovery of A Kinase Anchoring Proteins (AKAPs) has helped to unravel this mystery. AKAPs function to target PKA to specific regions within the cell. They also anchor other enzymes, receptors, or channels leading to tightly regulated signaling modules. Several studies have suggested an important role for activated PKA in these complexes, including the AKAPs yotiao and muscle AKAP (mAKAP). Yotiao, a plasma membrane AKAP, anchors PP1, NMDA receptors, IP3 receptors, and heart potassium channel subunit KCNQI. PKA phosphorylation of NMDA receptors as well as KCNQI leads to increased channel activity. Patients with mutations in KCNQI or yotiao that cause loss of targeting of KCNQI develop long QT syndrome, which can be fatal. mAKAP anchors several CAMP/PKA-regulated pathways to the nuclear envelope in cardiac myocytes. The necessity of activated PKA in these complexes led to the hypothesis that AC is also anchored. The results indicate that AC does associate with yotiao in brain and heart, specifically with AC types I-III, and IX. Co-expression of AC II or III with yotiao leads to inhibition of each isoform's activity. Binding assays revealed that yotiao binds to the N-terminus of AC II and that this region can reverse the inhibition of AC II, but not AC III, indicating unique binding sites on yotiao. AC II binds directly to as 808-957 of yotiao. Y808-957 acts as a dominant negative as the addition of it to rat brain membranes results in a ∼40% increase in AC activity. Additionally, AC was also found to associate with mAKAP in heart, specifically with AC types II and V. The binding site of AC was mapped to 275-340 of mAKAP, while mAKAP binds to the soluble domains of AC V as a complex. These results indicate that interactions between AC and AKAPs are specific and that AC plays an important role in AKAP-targeted signaling. ^

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Background. Large field studies in travelers' diarrhea (TD) in multiple destinations are limited by the need to perform stool cultures on site in a timely manner. A method for the collection, transport and storage of fecal specimens that does not require immediate processing, refrigeration and is stable for months would be advantageous. ^ Objectives. Determine if enteric pathogen bacterial DNA can be identified in cards routinely used for evaluation of fecal occult blood. ^ Methods. U.S. students traveling to Mexico in 2005-07 were followed for occurrence of diarrheal illness. When ill, students provided a stool specimen for culture and occult blood by the standard method. Cards were then stored at room temperature prior to DNA extraction. A multiplex fecal PCR was performed to identify enterotoxigenic Escherichia coli and enteroaggregative E. coli (EAEC) in DNA extracted from stools and occult blood cards. ^ Results. Significantly more EAEC cases were identified by PCR done in DNA extracted from cards (49%) or from frozen feces (40%) than by culture followed by HEp-2 adherence assays (13%). Similarly more ETEC cases were detected in card DNA (38%) than fecal DNA (30%) or culture followed by hybridization (10%). Sensitivity and specificity of the card test was 75% and 62%, respectively, and 50% and 63%, respectively, when compared to EAEC and ETEC culture, respectively, and 53% and 51%, respectively compared to EAEC multiplex fecal PCR and 56% and 70%, respectively, compared to ETEC multiplex fecal PCR. ^ Conclusions. DNA extracted from fecal cards used for detection of occult blood is of use in detecting enteric pathogens. ^

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Purpose. To develop a greater understanding of the experience—including the thoughts, feelings, and actions—of mothers' initiation and maintenance of lactation within the context of the NICU following the birth of a very preterm infant. ^ Design. Mixed method with dominant focused ethnographic approach. Setting: A 76-bed neonatal intensive care unit in the largest children's hospital located in a large metropolitan city in southeast Texas. ^ Sample. Purposeful sampling resulted in 23 interviews with 14 subjects. ^ Methods. Mixed method design with a dominant qualitative approach combined with a quantitative component to further identify and expand upon the investigation of the population in question. Open-ended semi-structured interviews and fieldwork were used to explore the experience of breastfeeding in the context of the NICU for mothers of very preterm infants. Longitudinal data obtained from each subject included in-depth interviews, demographic and clinical information, milk expression patterns (including pumping frequency, duration, and milk volumes obtained), and scores obtained from the Edinburgh Postpartum Depression Scale (EPDS). ^ Findings. Thematic analysis revealed that mothers of very preterm infants experienced an interruption in the process of becoming a mother, a paradoxical experience related to aspects of their milk expression routines and patterns, and negotiating the NICU environment. Sub-themes of becoming a mother-interrupted included: attribution, separation, connection, and navigation. Additional sub-themes related to the paradoxical experience included: the pump sometimes acting as a wedge or link to the infant; diversionary thoughts/activities during pumping; and perceptions of milk flow/volume. The process of negotiation included the environment, adaptive/maladaptive strategies related to milk expression, motivating factors related to the provision of breast milk, and learning their infant's feeding cues/abilities. EPDS scores did not reveal congruent differences in those mothers scoring high compared to those scoring low. ^ Conclusions. Understanding the experiences of the mothers in this study allows for a better perspective of breastfeeding the very preterm infant in the context of the NICU. Findings from this study validate the difficult and incremental process of attaining maternal identity and the significant burden placed on these women with regards to the provision of breast milk and breastfeeding during their infant's hospitalization. ^

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Overexpression of insulin-like growth factor binding protein 2 (IGFBP2) is associated with progression and poor survival in many types of human cancer (such as prostate, ovarian, adrenocortical, breast, colorectal carcinomas, leukemia, and high-grade gliomas). We therefore hypothesize that IGFBP2 is a key regulator of tumor progression. We tested our hypothesis in gliomas using the somatic gene transfer RCAS-tva mouse model system, which permits the introduction of specific genes into specific, cell lineages, in this case glial cells (RCAS: Replication competent avian sarcomavirus, tv-a: avian RCAS virus receptor). Mice are transgenic and harbor the tv-a receptor under the control of a glial-specific promoter and study genes are cloned into the RCAS vector for post-natal intracranial delivery. For these experiments, the study genes were IGFBP2, platelet-derived growth factor B (PDGFB), K-Ras, Akt, and IIp45 (invasion inhibitory protein 45 kDa; known to bind and block IGFBP2 activity), which were delivered separately and in combination. Our results show that PDGFB signaling leads exclusively to the formation of low-grade (WHO grade II) oligodendrogliomas. PDGFB delivered in combination with IGFBP2 results in the formation of anaplastic oligodendrogliomas (WHO grade III), which are characterized by increased cellularity, vascular proliferation, small regions of necrosis, increased mitotic activity, and increased activation of the Akt pathway. IIp45 injected in combination with PDGFB and IGFBP2 ablates IGFBP2-induced tumor progression, which results in formation of low-grade oligodendrogliomas, and an overall reduction in tumor incidence. K-Ras expression was required to form astrocytomas with either IGFBP2 or Akt, indicating the activation of two separate pathways is necessary for gliomagenesis. In ex vivo experiments, blockade of Akt by an inhibitor led to decreased viability of cells co-expressing IGFBP2 versus PDGFB expression alone. This study provides definitive evidence, for the first time, that: (1) IGFBP2 plays a role in activation of the Akt pathway, (2) IGFBP2 collaborates with K-Ras or PDGFB in the development and progression of two major types of glioma, and (3) IGFBP2-induced tumor progression can be ablated by IIp45 or by specific inhibition of the Akt pathway. ^

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Several immune pathologies are the result of aberrant regulation of T lymphocytes. Pronounced T cell proliferation can result in autoimmunity or hematologic malignancy, whereas loss of T cell activity can manifest as immunodeficiency. Thus, there is a critical need to characterize the signal transduction pathways that mediate T cell activation so that novel and rational strategies to detect and effectively control T cell mediated disease can be achieved. ^ The first objective of this dissertation was to identify and characterize novel T cell regulatory proteins that are differentially expressed upon antigen induced activation. Using a functional proteomics approach, two members of the prohibitin (Phb) family of proteins, Phb1 and Phb2, were determined to be upregulated upon activation of primary human T cells. Furthermore, their regulated expression was dependent upon CD3 and CD28 signaling pathways which synergistically increased their expression. In contrast to previous reports of Phb nuclear localization, both proteins were determined to localize to the mitochondrial inner membrane of human T cells. Additionally, novel Phb phosphorylation sites were identified and characterized using mass spectrometry, phosphospecific antibodies and site directed mutagenesis. ^ Prohibitins have been proposed to play important roles in cancer development however the mechanism of action has not been elucidated. The second objective of this dissertation was to define the functional role of Phbs in T cell activity, survival and disease. Compared to levels in normal human T cells, Phb expression was higher in the human tumor T cell line Kit225 and subcellularly localized to the mitochondrion. Ablation of Phb expression by siRNA treatment of Kit225 cells resulted in disruption of mitochondrial membrane potential and significantly enhanced their sensitivity to cell death, suggesting they serve a protective function in T cells. Furthermore, Q-RT-PCR analysis of human oncology cDNA expression libraries indicated the Phbs may represent hematological cancer biomarkers. Indeed, Phb1 and Phb2 protein levels were 6-10 fold higher in peripheral blood mononuclear cells isolated from malignant lymphoma and multiple myeloma patients compared to healthy individuals. ^ Taken together, Phb1 and Phb2 are novel phosphoproteins upregulated during T cell activation and transformation to function in the maintenance of mitochondrial integrity and perhaps energy metabolism, thus representing previously unrecognized intracellular biomarkers and therapeutic targets for regulating T cell activation and hematologic malignancies. ^

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This retrospective, case-control study investigated the effectiveness of the Houston, Texas Ask Your Nurse Advice Line (AYN) in diverting callers with non-emergent medical conditions away from the emergency department (ED). After asking callers a series of questions, AYN nurses evaluate the medical condition and make recommendations for appropriate care, e.g., home care, see a clinic physician, or visit the ED. To evaluate the AYN, the rate of caller ED visits before accessing the AYN for the first time was compared to the caller ED visit rate afterwards. The pre-post rate change was compared to that of a control group of similar caller age, race, gender, and insurance status drawn from a Harris County Hospital District HCHD database. ^ The treatment group (AYN caller) had a 66% reduction in ED visits after the first AYN call compared to an 18% drop in ED visits among control group subjects during the same time period. Study results were presented to HCHD staff on August 30th, 2007 and recommendations were made for future studies that would provide a basis for policy development. ^

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The cause of infection of about a third of all travelers' diarrhea patients studied is not identified. Stools of these diarrhea patients tested for known enteric pathogens are shown to be negative, and identified as pathogen negative stools. We proposed that the third of these diarrhea patients might not only include at present unknown pathogens, but also known pathogens that go undetected. Conventionally, a probability sample of five E. coli colonies are used detect enterotoxigenic E. coli (ETEC) and other diarrhea-producing E. coli from stool cultures. We compared this conventional method of using five E. coli colonies, to the use of up to twenty E. coli colonies. Testing for up to fifteen E. coli colonies detected about twice as many ETEC when compared to the detection of ETEC, testing for five E. coli colonies. When the number of E. coli colonies tested was increased from 5 to 15, the detection of ETEC increased from 19.0% to 38.8%. The sensitivity of the assay with 5 E. coli colonies was statistically significantly different to the sensitivity of the assay with 10 E. coli colonies, suggesting that for the detection of ETEC at least 10 colonies of E. coli should be tested.^

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Background. Parkinson's disease is a chronic, progressive, age-related, neurodegenerative disorder with no known cause or promising cure. While substantial information is known about the pathophysiology of Parkinson's disease, little is known about the illness experience of persons living with the disease. The purpose of this study was to understand how persons with Parkinson's disease construct their illness experience and manage living with their illness on a daily basis. ^ Method. A qualitative study with an ethnographic approach employed the strategies of participant observations and fieldwork. Field data were generated from a two year exposure to two Parkinson's disease support groups in east Texas. Open-ended semi-structured interviews with seven men and seven women with Parkinson's disease were also conducted. These data were combined and analyzed using thematic analysis. ^ Findings. The illness experience is described through the metaphor "Sailing the Sea in The Eye of the Storm." This metaphor served as the overarching theme that covered the two interacting content themes of the voyage of Daily Negotiations in the Midst of Uncertainty and Reconstruction of the Self with Parkinson's Disease. Daily negotiations incorporated navigating daily activities with the uncertainty of both the progression and daily vicissitudes of the disease. Participants described their symptoms as progressive imprisonment that interfered with daily activities. The progressive nature of the disease required the participants to reconstruct their perceptions of themselves. Reconstructing the self involved the paradoxical balancing of preserving the self while simultaneously releasing aspects of the former self to reconstruct the self with Parkinson's disease. This process was reflected in four exemplars: I Know Me." "It's Still Me," "See Me." and "Remember Me." ^ Conclusions. This qualitative study illuminated the struggle of persons in dealing with the uncertainties and fluctuations of Parkinson's disease and the process of reconstructing their perceptions of themselves. The meaning and reconstruction of the illness experience expressed by participants will inform understanding beyond the disease itself to the illness experience that these participants must deal with on a daily basis. ^

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Study purpose. Genetic advances are significantly impacting healthcare, yet recent studies of ethnic group participation in genetic services demonstrate low utilization rates by Latinos. Limited genetic knowledge is a major barrier. The purpose of this study was to field test items in a Spanish-language instrument that will be used to measure genetic knowledge relevant to type 2 diabetes among members of the ethnically heterogeneous U.S. Latino community. Accurate genetic knowledge measurement can provide the foundation for interventions to enhance genetic service utilization. ^ Design. Three waves of cognitive interviews were conducted in Spanish to field test 44 instrument items Thirty-six Latinos, with 12 persons representative of Mexican, Central and South American, and Cuban heritage participated, including 7 males and 29 females between 22 and 60 years of age; 17 participants had 12 years or less of education. ^ Methods. Text narratives from transcriptions of audiotaped interviews were qualitatively analyzed using a coding strategy to indicate potential sources of response error. Through an iterative process of instrument refinement, codes that emerged from the data were used to guide item revisions at the conclusion of each phase; revised items were examined in subsequent interview waves. ^ Results. Inter-cultural and cross-cultural themes associated with difficulties in interpretation and grammatical structuring of items were identified; difficulties associated with comprehension reflected variations in educational level. Of the original 44 items, 32 were retained, 89% of which were revised. Six additional items reflective of cultural knowledge were constructed, resulting in a 38-item instrument. ^ Conclusions. Use of cognitive interviewing provided a valuable tool for detecting both potential sources of response error and cultural variations in these sources. Analysis of interview data guided successive instrument revisions leading to improved item interpretability and comprehension. Although testing in a larger sample will be essential to test validity and reliability, the outcome of field testing suggests initial content validity of a Spanish-language instrument to measure genetic knowledge relative to type 2 diabetes. ^ Keywords. Latinos, genetic knowledge, instrument development, cognitive interviewing ^

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Background. Ambulatory blood pressure (ABP) measurement is a means of monitoring cardiac function in a noninvasive way, but little is known about ABP in heart failure (HF) patients. Blood pressure (BP) declines during sleep as protection from consistent BP load, a phenomenon termed "dipping." The aims of this study were (1) to compare BP dipping and physical activity between two groups of HF patients with different functional statuses and (2) to determine whether the strength of the association between ambulatory BP and PA is different between these two different functional statuses of HF. ^ Methods. This observational study used repeated measures of ABP and PA over a 24-hour period to investigate the profiles of BP and PA in community-based individuals with HF. ABP was measured every 30 minutes by using a SpaceLabs 90207, and a Basic Motionlogger actigraph was used to measure PA minute by minute. Fifty-six participants completed both BP and physical activity for a 24-hour monitoring period. Functional status was based on New York Heart Association (NYHA) ratings. There were 27 patients with no limitation of PA (NYHA class I HF) and 29 with some limitation of PA but no discomfort at rest (NYHA class II or III HF). The sample consisted of 26 men and 30 women, aged 45 to 91 years (66.96 ± 12.35). ^ Results. Patients with NYHA class I HF had significantly greater dipping percent than those with NYHA class II/III HF after controlling their left ventricular ejection fraction (LVEF). In a mixed model analysis (PROC MIXED, SAS Institute, v 9.1), PA was significantly related to ambulatory systolic and diastolic BP and mean arterial pressure. The strength of the association between PA and ABP readings was not significantly different for the two groups of patients. ^ Conclusions. These preliminary findings demonstrate differences between NYHA class I and class II/III of HF in BP dipping status and ABP but not PA. Longitudinal research is recommended to improve understanding of the influence of disease progression on changes in 24-hour physical activity and BP profiles of this patient population. ^ Key Words. Ambulatory Blood Pressure; Blood Pressure Dipping; Heart Failure; Physical Activity. ^

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Purpose. Understanding siblings' experiences after a major childhood burn injury was the purpose of this mixed method, qualitative dominant study. The following research questions guided this project: How do siblings describe the impact of a major childhood burn injury experience? How do sibling relationship factors of warmth/closeness, relative status/power, conflict, and rivalry further clarify their relationship and their experience after a major burn injury? ^ Methods. A mixed method, qualitative dominant, design was implemented to understand the sibling experiences in a family with a child suffering from a major burn injury. Informants were selected from patients with childhood burn injuries attending the reconstructive clinic at a Gulf coast children's specialty hospital. The qualitative portion used the life story method, a narrative process, to portray the long-term impact on sibling relationships. A "case" represents a family unit and could be composed of one or multiple family members. Participants from 22 cases (N = 40 participants) were interviewed. Interviews were conducted in person and via telephone. The quantitative portion, or the embedded part of this mixed method design, used the Sibling Relationship Questionnaire Revised (SRQ-R) to conduct an additional structured interview and acquire scoring data. It was postulated that the SRQ-R would provide another perspective on the sibling experience and expand the qualitative data analysis. Thematic analysis was implemented on the qualitative interview data including the qualitative data from the interviews structured on the SRQ-R. Additionally, scores on the SRQ-R were tabulated to further describe the cases. ^ Results. The overall thematic pattern for the sibling relationship in families having a child with a major burn injury was that of normalization. Areas of normalization as well as the process of adjustment were the major themes. Areas of normalization were found in play and other activities, in school and work, and in family relations with their siblings and their parents. The process of adjustment in the sibling relationship was described as varied, involved school and work re-entry, and might even change their life perspective. Further analysis included an examination of the cases in which more than one person were interviewed and completed the SRQ-R. Participants from five ( n = 11) of six cases (n = 14), scored above 3.0 on the five-point scale on the Warmth/Closeness construct, indicating they perceived the sibling relationship as close. Five participants scored high on the Conflict construct and four participants scored high on the Rivalry construct. Finally, Relative Status/Power was low or negative in the six cases (n = 13). ^ Conclusions/implications. These findings suggest the importance of returning to normalcy for many of the families and the significance of sibling relationships on the process. Some of these families were able to use this major life event in a positive way to promote normalization. ^

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Trimethylaminuria (TMAU) or Fish odor syndrome is an autosomal recessive disease that is characterized by pungent body odor with subsequent psychosocial complications. There are limited studies of the sequence variants causing TMAU in the literature with most studies describing only one or two patients and lacking genotype-phenotype correlations. Also to date, there is no laboratory in the US or Europe that offers TMA genetic testing on a clinical basis. We have recently validated genetic testing in the University of Colorado DNA Diagnostic Laboratory. We have a database of a few dozen patients with a biochemical diagnosis of TMA at the University of Colorado at Denver Health Sciences Center (UCDHSC) which includes a few patients with the classical form of the disease. We have used the newly established clinical test in our institution to attempt to characterize the genotype (sequence variants including mutations and polymorphisms) of classical TMAU patients and to establish a genotype-phenotype (biochemical and clinical) association. The questionnaire results confirmed most of the previously reported epidemiological findings of TMAU and also indicated that TMAU patients use multiple intervention measures in attempt to control their symptoms with dietary control being most effective. Despite the complexity of intervention, most patients did not have any medical follow up and there was underutilization of specialist care. In a set of our patients, two deleterious mutations were identified in 4/12 patients including a novel T237P sequence variant, while the majority of our patients (8/12) did not reveal any mutations. Some of the latter were double heterozygous for the E158K and E308G polymorphisms which could explain a mild phenotype while others had only the E158K variant which raised the question of undetected mutations. These results indicate that further experiments are needed to further delineate the full mutational spectrum of the FMO3 gene. ^