Mutations affecting the SAND domain of DEAF1 cause intellectual disability with severe speech impairment and behavioral problems.

Recently, we identified in two individuals with intellectual disability (ID) different de novo mutations in DEAF1, which encodes a transcription factor with an important role in embryonic development. To ascertain whether these mutations in DEAF1 are causative for the ID phenotype, we performed targeted resequencing of DEAF1 in an additional cohort of over 2,300 individuals with unexplained ID and identified two additional individuals with de novo mutations in this gene. All four individuals had severe ID with severely affected speech development, and three showed severe behavioral problems. DEAF1 is highly expressed in the CNS, especially during early embryonic development. All four mutations were missense mutations affecting the SAND domain of DEAF1. Altered DEAF1 harboring any of the four amino acid changes showed impaired transcriptional regulation of the DEAF1 promoter. Moreover, behavioral studies in mice with a conditional knockout of Deaf1 in the brain showed memory deficits and increased anxiety-like behavior. Our results demonstrate that mutations in DEAF1 cause ID and behavioral problems, most likely as a result of impaired transcriptional regulation by DEAF1.

Retrieval of morphine-associated context induces cFos in dentate gyrus neurons.

Addiction has been proposed to emerge from associations between the drug and the reward-associated contexts. This associative learning has a cellular correlate, as there are more cFos+ neurons in the hippocampal dentate gyrus (DG) after psychostimulant conditioned place preference (CPP) versus saline controls. However, it is unknown whether morphine CPP leads to a similar DG activation, or whether DG activation is due to locomotion, handling, pharmacological effects, or-as data from contextual fear learning suggests-exposure to the drug-associated context. To explore this, we employed an unbiased, counterbalanced, and shortened CPP design that led to place preference and more DG cFos+ cells. Next, mice underwent morphine CPP but were then sequestered into the morphine-paired (conditioned stimulus+ [CS+]) or saline-paired (CS-) context on test day. Morphine-paired mice sequestered to CS+ had ∼30% more DG cFos+ cells than saline-paired mice. Furthermore, Bregma analysis revealed morphine-paired mice had more cFos+ cells in CS+ compared to CS- controls. Notably, there was no significant difference in DG cFos+ cell number after handling alone or after receiving morphine in home cage. Thus, retrieval of morphine-associated context is accompanied by activation of hippocampal DG granule cell neurons.

Components of the COPD Assessment Test (CAT) associated with a diagnosis of COPD in a random population sample.

The aim of this study was to determine if components of the COPD Assessment Test (CAT), a validated health status impairment instrument, had additional utility in identifying patients at risk for COPD in whom spirometry testing is appropriate. This study was part of the Canadian Obstructive Lung Disease prevalence study. Consenting participants ≥ 40 years of age were identified by random digit dialing. Smoking history, 8-item CAT scores, and post-bronchodilator spirometry were recorded for each. Stepwise logistic regression analysis was used to identify variables related to the presence of airway obstruction and a final logistic model was developed which best predicted COPD in this sample. Of the 801 individuals approached, 532 were included: 51 (9.6%) had COPD, the majority (92%) of whom fit GOLD I or II severity criteria. Items that correlated significantly with a COPD diagnosis included the CAT total score (p = 0.01) and its breathlessness (p < 0.0001) and phlegm (p = 0.001) components. The final logistic model included: age (<55 or ≥55 years), smoking status (current, former, never) and the CAT breathlessness score (ordinal scale 0-5). The area under the receiver-operating characteristic curve for this model was 0.77, sensitivity was 77.6%, specificity was 64.9% and the positive likelihood ratio was 2.21. In summary, the triad of smoking history, age at least 55 years and the presence of exertional breathlessness were key elements of a simple model which had reliable measurement properties when tested in a random population. This may help identify patients at risk for COPD for whom spirometry testing is recommended.

Evaluation of LAMP for detection of Shigella from stool samples in children.

BACKGROUND: To assess the diagnostic accuracy of loop-mediated isothermal amplification (LAMP) for the detection of Shigella from stool samples from children. METHODS: Consecutive stool samples from children aged <13 years old who presented with acute watery diarrhoea or dysentery to the Department of Paediatrics were collected and processed in the Department of Microbiology. All the stool samples were subjected to culture, conventional PCR and LAMP. Genomic sequencing was performed for samples that were positive by LAMP but negative by both culture and conventional PCR. The LAMP results were compared to those from culture and to a composite reference standard based on culture and conventional PCR. RESULTS: Amongst the 374 stool samples tested, 291 samples were positive by LAMP and 213 were positive by the composite reference standard. The sensitivity of LAMP was 100 % (98.3-100 %) and its specificity was 51.6 % (43.6-59.5 %) with a disease prevalence of 57 %. The sensitivity and specificity of LAMP improved to 99.3 % (94.2-100) and 98.2 % (94.5-99.9), respectively, using latent class analysis, while assuming that genomic sequencing has perfect specificity. DISCUSSION: The authors have standardized the LAMP procedure for direct application to clinical stool samples. LAMP is a sensitive and specific method for the diagnosis of Shigella from stool samples of children as compared to both culture and conventional PCR.

Iron homeostasis is dysregulated, but the iron-hepcidin axis is functional, in chronic liver disease.

BACKGROUND: Perturbations in iron homeostasis have been reported to be associated with irreversible liver injury in chronic liver disease (CLD). However, it is not clear whether liver dysfunction per se underlies such dysregulation or whether other factors also contribute to it. This study attempted to examine the issues involved. METHODS: Patients diagnosed to have chronic liver disease (n = 63), who underwent a medically-indicated upper gastrointestinal endoscopy, were the subjects of this study. Patients with dyspepsia, who underwent such a procedure, and were found to have no endoscopic abnormalities, were used as control subjects (n = 49). Duodenal mucosal samples were obtained to study mRNA and protein levels of duodenal proteins involved in iron absorption. A blood sample was also obtained for estimation of hematological, iron-related, inflammatory and liver function-related parameters. RESULTS: Patients with CLD had impaired liver function, anemia of inflammation and lower serum levels of hepcidin than control subjects. Gene (mRNA) expression levels of duodenal ferroportin and duodenal cytochrome b (proteins involved in iron absorption) were decreased, while that of divalent metal transporter-1 (DMT-1) was unchanged. Protein expression of DMT-1 was, however, decreased while that of ferroportin was unchanged. In the CLD group, serum hepcidin was predicted independently by serum ferritin and hemoglobin, but not by C-reactive protein (a marker of inflammation). CLD patients with serum ferritin greater than 300 µg/dL had significantly greater liver dysfunction (as indicated by significantly higher serum concentrations of bilirubin, AST and ALT, and MELD scores), higher serum concentrations of CRP and hepcidin, and higher ferroportin protein expression, than those with serum ferritin ≤ 300 µg/dL. CONCLUSIONS: In patients with CLD, anemia of inflammation and low serum hepcidin levels were found to paradoxically co-exist. Expression of duodenal proteins involved in iron absorption were either decreased or unaltered in these patients. The hepcidin response to higher body iron levels and/or inflammation appeared to be functional in these patients, despite the presence of liver disease.

An unusual case of hyalohyphomycosis due to Purpureocillium lilacinum in a patient with myasthenia gravis.

BACKGROUND AND PURPOSE: Purpureocillium lilacinum (previously known as Paecilomyces lilacinus) and Paecilomyces variotii cause hyalohyphomycosis. CASE REPORT: In this study, we present a case of multiple subcutaneous abscesses of the lower limbs due to Purpureocillium lilacinum in a patient with myasthenia gravis and uncontrolled diabetes. Subcutaneous involvement of the lower limbs with this fungus is an unusual presentation. Pus aspirate collected on multiple occasions revealed hyaline septate hyphae under microscopic examination and Purpureocillium lilacinum grew on Sabouraud Dextrose Agar. The patient was initially treated by surgical excision and itraconazole therapy. Swelling regressed but discharge was noticed from the excision site after three months of itraconazole therapy. Culture from the discharge material yielded the same fungal growth. Treatment was changed to ketoconazole and he responded. CONCLUSION: This case report emphasizes the importance of identifying Purpureocillium lilacinum at an unusual site like the lower limbs in an immunocompromised patient. Ketoconazole may be used as an alternative treatment option for hyalohyphomycosis caused by Purpureocillium lilacinum.

Timing of bypass surgery in stable patients after acute myocardial infarction.

OBJECTIVES: To determine the optimal timing for bypass surgery in stable patients after acute myocardial infarction (MI). BACKGROUND: Coronary artery bypass graft surgery (CABG) is a proven treatment for coronary artery disease. Because of the hypothesized risk of hemorrhagic transformation, it had become common practice to wait four to six weeks after MI. Recently, improvements in surgical and perioperative management, as well as an increase in pre-CABG in-hospital waiting times and excess burden on health care resources, have pushed surgeons to operate earlier. The optimal timing for a stable patient to undergo CABG after MI is unclear, because there have been no randomized trials to answer this question. METHODS: The published literature comparing early versus late surgical revascularization procedures in stable post-MI patients was reviewed. RESULTS: No randomized, prospective trials were found; however, several retrospective studies were identified. Most series examining Q wave MIs showed that mortality is higher in the early stages post-MI and progressively decreases with time post-MI. When studies examined non-Q wave MIs separately, there appeared to be less of a mortality difference between early and late surgical revascularization. There was a large disparity between the definitions of early surgery post-MI among the studies, some as early as 6 h and others up to eight days. Factors that increased mortality include abnormal left ventricular function and urgency of surgery, and some studies found risk models helpful to define increased risk after infarction. The possible increased risk of early surgery may be balanced against the potential for improved remodelling, improved quality of life and decreased hospital stay costs. CONCLUSIONS: There is a need for a randomized, prospective trial examining the optimal timing for CABG in stable post-MI patients.

Long-term prognosis of south Asians following acute coronary syndromes.

BACKGROUND: South Asians (SAs) have a higher prevalence of coronary artery disease than Caucasians. The long-term prognosis following acute coronary syndromes (ACS) in SA compared with non-SA patients is unclear. OBJECTIVES: To compare the long-term adverse cardiovascular outcomes between SA and non-SA patients who have ACS. METHODS: A case-control study of 65 consecutive SA patients admitted with ACS to the McGill University Health Centre (Montreal, Quebec) between 1995 and 2000 was conducted. Control subjects included 65 non-SA patients admitted to the same hospital with ACS matched by age, sex and year of hospitalization. RESULTS: The mean +/- SD age was 59.7+/-9.9 years and 12% of patients were women. There were more cases of diabetes mellitus among the SA patients than non-SA patients (43% versus 23%, respectively). Only 19% of SA patients were active smokers, compared with 34% of non-SA patients. At one year, 35% of SA patients had undergone coronary artery bypass graft surgery, compared with 22% of non-SA patients. One-year mortality was increased among the SA patients compared with the non-SA patients (6% versus 2%, respectively). However, SA ethnicity was not an independent predictor of one-year adverse cardiovascular outcomes. CONCLUSIONS: The present study demonstrated an increased prevalence of diabetes mellitus among the SA patients with ACS compared with non-SA patients. SA patients had increased one-year mortality compared with non-SA patients. However, SA ethnicity was not an independent predictor of one-year mortality and coronary intervention.

Tricuspid valve replacement after cardiac transplantation.

BACKGROUND: Tricuspid regurgitation (TR) occurs commonly in transplanted hearts. Although theoretically attractive, tricuspid valve replacement (TVR) has not been widely investigated as a possible therapy in post-transplant patients. The purpose of this study was to determine the safety of TVR in heart transplant patients and its effects on measurable clinical endpoints. METHODS: We acquired data by both retrospective chart review and prospective data collection in all patients who underwent TVR after cardiac transplantation. RESULTS: Nine patients were identified and followed for a period of six months. The age of patients at time of TVR was 62 +/- 6.1 yr and their average time since transplantation was 12 +/- 3.2 yr. Most patients demonstrated a reduction in their furosemide dose (105 +/- 63 mg/d pre-TVR vs. 67.5 +/- 65 mg/d post-TVR, p = 0.001) with a reduction in serum creatinine levels (188 +/- 72 micromol/L pre-TVR vs. 143 +/- 42 micromol/L post-TVR, p = 0.06). Additionally, we found a significant improvement in albumin values (32 +/- 5 g/L pre-TVR vs. 42 +/- 3 g/L post-TVR, p = 0.002) as well as an improvement in total bilirubin (35 +/- 18 micromol/L pre-TVR vs. 18 +/- 5 micromol/L post-TVR, p = 0.05). There was only one death in our series, in the only patient with known severe graft atherosclerosis. CONCLUSIONS: TVR appears to be a safe procedure in patients without severe graft atherosclerosis with improvements in serum creatinine, albumin and total bilirubin values, in addition to a reduction in furosemide dose. This may reflect improved forward flow, improved symptomatology from TR as well as possible beneficial effects on nutritional status.