Wilson's Disease.

Wilson's disease (WD) can present with liver disease, neurological deficits, and psychiatric disorders. Results of genetic prevalence studies suggest that WD might be much more common than previously estimated. Early recognition of WD remains challenging because it is a great imitator and requires a high index of suspicion for correct and timely diagnosis. Early diagnosis of WD is crucial to ensure that patients can be started on adequate treatment. In association with other clinical and biochemical tests, liver biopsy results and molecular genetic testing can also be used for diagnosing WD. Medical therapy is effective for most patients; liver transplant can rescue those with acute liver failure or those with advanced liver disease who fail to respond to or discontinue medical therapy. Although novel therapies, such as gene therapy, are on the horizon, screening and prevention of delayed diagnosis remains paramount.

Current Status of Celiac Disease Drug Development.

Celiac disease (CeD) is one of the most common immune-mediated diseases. Symptoms and disease activity are incompletely controlled by the gluten-free diet, which is currently the only available therapy. Although no therapies are yet approved, there is a growing field of candidates and an improving understanding of the regulatory pathway. In this review, we briefly discuss the epidemiology, pathophysiology, and current treatment paradigm for CeD. We also review the major classes of therapies being considered for CeD and discuss extensively what is known and can be surmised regarding the regulatory pathway for approval of a CeD therapeutic. The coming years will see an increasing number and diversity of potential therapies entering clinical trials and hopefully the first approved agents targeting this significant unmet medical need. Although biomarkers including histology and serology will always be important in therapeutic clinical trials, they currently lack the necessary evidence linking them to improved patient outcomes required for use as primary outcomes for drug approval. For this reason, patient-reported outcomes will likely be primary end points in Phase III CeD trials for the foreseeable future.

Development and Validation of Digital Enzyme-Linked Immunosorbent Assays for Ultrasensitive Detection and Quantification of Clostridium difficile Toxins in Stool.

The currently available diagnostics for Clostridium difficile infection (CDI) have major limitations. Despite mounting evidence that toxin detection is paramount for diagnosis, conventional toxin immunoassays are insufficiently sensitive and cytotoxicity assays too complex; assays that detect toxigenic organisms (toxigenic culture [TC] and nucleic acid amplification testing [NAAT]) are confounded by asymptomatic colonization by toxigenic C. difficile. We developed ultrasensitive digital enzyme-linked immunosorbent assays (ELISAs) for toxins A and B using single-molecule array technology and validated the assays using (i) culture filtrates from a panel of clinical C. difficile isolates and (ii) 149 adult stool specimens already tested routinely by NAAT. The digital ELISAs detected toxins A and B in stool with limits of detection of 0.45 and 1.5 pg/ml, respectively, quantified toxins across a 4-log range, and detected toxins from all clinical strains studied. Using specimens that were negative by cytotoxicity assay/TC/NAAT, clinical cutoffs were set at 29.4 pg/ml (toxin A) and 23.3 pg/ml (toxin B); the resulting clinical specificities were 96% and 98%, respectively. The toxin B digital ELISA was 100% sensitive versus cytotoxicity assay. Twenty-five percent and 22% of the samples positive by NAAT and TC, respectively, were negative by the toxin B digital ELISA, consistent with the presence of organism but minimal or no toxin. The mean toxin levels by digital ELISA were 1.5- to 1.7-fold higher in five patients with CDI-attributable severe outcomes, versus 68 patients without, but this difference was not statistically significant. Ultrasensitive digital ELISAs for the detection and quantification of toxins A and B in stool can provide a rapid and simple tool for the diagnosis of CDI with both high analytical sensitivity and high clinical specificity.

Arsenic as an endocrine disruptor: arsenic disrupts retinoic acid receptor-and thyroid hormone receptor-mediated gene regulation and thyroid hormone-mediated amphibian tail metamorphosis.

BACKGROUND: Chronic exposure to excess arsenic in drinking water has been strongly associated with increased risks of multiple cancers, diabetes, heart disease, and reproductive and developmental problems in humans. We previously demonstrated that As, a potent endocrine disruptor at low, environmentally relevant levels, alters steroid signaling at the level of receptor-mediated gene regulation for all five steroid receptors. OBJECTIVES: The goal of this study was to determine whether As can also disrupt gene regulation via the retinoic acid (RA) receptor (RAR) and/or the thyroid hormone (TH) receptor (TR) and whether these effects are similar to previously observed effects on steroid regulation. METHODS AND RESULTS: Human embryonic NT2 or rat pituitary GH3 cells were treated with 0.01-5 microM sodium arsenite for 24 hr, with or without RA or TH, respectively, to examine effects of As on receptor-mediated gene transcription. At low, noncytotoxic doses, As significantly altered RAR-dependent gene transcription of a transfected RAR response element-luciferase construct and the native RA-inducible cytochrome P450 CYP26A gene in NT2 cells. Likewise, low-dose As significantly altered expression of a transfected TR response element-luciferase construct and the endogenous TR-regulated type I deiodinase (DIO1) gene in a similar manner in GH3 cells. An amphibian ex vivo tail metamorphosis assay was used to examine whether endocrine disruption by low-dose As could have specific pathophysiologic consequences, because tail metamorphosis is tightly controlled by TH through TR. TH-dependent tail shrinkage was inhibited in a dose-dependent manner by 0.1- 4.0 microM As. CONCLUSIONS: As had similar effects on RAR- and TR-mediated gene regulation as those previously observed for the steroid receptors, suggesting a common mechanism or action. Arsenic also profoundly affected a TR-dependent developmental process in a model animal system at very low concentrations. Because RAR and TH are critical for both normal human development and adult function and their dysregulation is associated with many disease processes, disruption of these hormone receptor-dependent processes by As is also potentially relevant to human developmental problems and disease risk.

Acute myeloid leukemia developing in a granulocyte colony-stimulating factor-mobilized stem cell donor: A case report and review of the literature.

We describe the first case of a FLT-3 mutated AML in a healthy donor, 3years after recombinant human granulocyte colony stimulating factor (rhG-CSF)-mobilized peripheral blood stem cell (PBSC) harvest. The patient had a myeloablative (MA) matched unrelated donor (MUD) stem cell transplant (SCT) for refractory AML. However, he experienced a secondary graft failure. He had a second non myeloablative (NMA) on day +75 from a second MUD. He achieved a complete neutrophil and platelet engraftment. After 4years of follow up, he is alive in complete remission with full second donor chimerism.

EP24.15 as a Potential Regulator of Kisspeptin Within the Neuroendocrine Hypothalamus.

The neuropeptide kisspeptin (Kiss1) is integral to the advent of puberty and the generation of cyclical LH surges. Although many complex actions of Kiss1 are known, the mechanisms governing the processing/regulation of this peptide have not been unveiled. The metallo enzyme, endopeptidase 24.15 (thimet oligopeptidase), has been demonstrated to play a key role in the processing and thus the duration of action of the reproductive neuropeptide, GnRH, which signals downstream of Kiss1. Initial in silico modeling implied that Kiss1 could also be a putative substrate for EP24.15. Coincubation of Kiss1 and EP24.15 demonstrated multiple cleavages of the peptide predominantly between Arg29-Gly30 and Ser47-Phe48 (corresponding to Ser5-Phe6 in Kiss-10; Kiss-10 as a substrate had an additional cleavage between Phe6-Gly7) as determined by mass spectrometry. Vmax for the reaction was 2.37±0.09 pmol/min · ng with a Km of 19.68 ± 2.53µM, which is comparable with other known substrates of EP24.15. EP24.15 immunoreactivity, as previously demonstrated, is distributed in cell bodies, nuclei, and processes throughout the hypothalamus. Kiss1 immunoreactivity is localized primarily to cell bodies and fibers within the mediobasal and anteroventral-periventricular hypothalamus. Double-label immunohistochemistry indicated coexpression of EP24.15 and Kiss1, implicating that the regulation of Kiss1 by EP24.15 could occur in vivo. Further studies will be directed at determining the precise temporal sequence of EP24.15 effects on Kiss1 as it relates to the control of reproductive hormone secretion and treatment of fertility issues.

The impact of PCR on Clostridium difficile detection and clinical outcomes.

PCR has increasingly replaced toxin A and B enzyme immunoassay (EIA) for the testing of Clostridium difficile infection (CDI). This study evaluated the clinical outcomes of CDI and disease epidemiology since the introduction of PCR. Clinical data and outcomes for patients admitted to a tertiary care centre during 2003 to 2012 were extracted using electronic medical records. Outcomes and incidence of disease were compared between types of CDI testing. In total, 15.6% of 108,092 patients admitted were tested for CDI. Among patients tested, 6.1% had positive results. The mean number of tests performed per 1000 admissions by EIA and PCR was 257.4 and 162.6, respectively. A total of 8.2% of PCR tests were positive compared to 5.0% of EIA tests (P < 0.001). The number of tests performed has decreased and the proportion of positive tests increased since PCR introduction. CDI incidence has remained constant. Only albumin (3.09 vs 3.24 g dl(-1), P 0.002) and inflammatory bowel disease (2.6 vs 7.0%, P < 0.001) status differed between the EIA and PCR groups. While hospital mortality did not differ, patients diagnosed by PCR had a shorter median length of stay (10 vs 8 days, P 0.004). Since PCR testing began, less CDI tests have been performed, but the proportion of positive results has increased. The incidence of CDI has remained constant, suggesting no change in disease epidemiology. The length of stay was shorter in the PCR group, reflective of either earlier detection and quicker onset of therapy or detection of less severe disease. Mortality did not change since the introduction of PCR.