Large-scale turbulence structures in a laboratory-scale boundary layer under steady and gusty wind inflows.

Experiments on turbulence structures and features of a wind field under steady inflow and gusty wind inflows were implemented in a straight-through wind tunnel. Streamwise and wall-normal velocity components were measured using a streamline constant temperature anemometer (streamline CTA). Power spectra analyses revealed the existence of very large-scale motions (VLSMs) under both steady and gusty wind inflows; but new gusty scale motions (GSMs) were revealed under only gusty wind inflows. The GSMs might originate from an ordered external driving force that forces hairpin packets to align coherently in groups with a length scale related to the gust inflow condition. The streamwise wavelength of VLSMs is independent of inflow conditions, while the turbulent energy of VLSMs is associated with the wall-normal height and local mean streamwise velocity. In particular, the streamwise wavelength of GSMs increases linearly with the average value and period of sinusoidal gusty wind inflows, and the turbulent energy of GSMs is sensitive to the wall-normal height and all characteristic parameters of gusty wind inflows, including the average value, amplitude and period. Considerable wall-normal airflows induced by gusty wind inflows were detected and these are negatively correlated with the variation in gusty streamwise velocity, and root mean square (RMS) values of the gusty wall-normal velocity tended to increase linearly with the average value and amplitude of gusty wind inflows.

Identification of a missense mutation of c.3064G>A, Gly1022Ser in exon 43 of COL1A1 gene in a girl with osteogenesis imperfecta type III.

Osteogenesis imperfecta (OI) types I-V have been inherited in an autosomal dominant pattern. OI type I is associated with mutations in COL1A1 mostly due to a null allele. OI types II-IV are associated with mutations in COL1A1 or COL1A2 and mostly are due to glycine substitutions. It has been suggested that the effect of glycine substitutions is position specific, and the substitution of glycine by serine has much less lethal effect than the substitutions by valine, aspartic acid, glutamic acid, arginine and cysteine. We report identification of c.3064G>A, GGT>AGT, Gly1022Ser (Gly(844) --> Ser844 in triple helix) in exon 43 of the COL1A1 gene in an 8-year-old girl with OI type III. Our report provides evidence that at triple helix glycine residue 844 (p.Gly1022), a glycine substitution by serine can result in OI type III but not a lethal outcome.

Partial monosomy 3p (3p26.2 --> pter) and partial trisomy 5q (5q34 --> qter) in a girl with coarctation of the aorta, congenital heart defects, short stature, microcephaly and developmental delay.

A 1-year-and-3-month-old girl presented with psychomotor retardation, developmental delay, clinodactyly of the thumb, coarctation of the aorta, patent ductus arteriosus, peripheral pulmonary stenosis, atrial septal defect, microcephaly, brachycephaly, a small oval face, almond-shaped eyes, a down-turned mouth, a widened nasal bridge, hypertelorism, epicanthic folds, long philtrum, low-set large ears and but no craniosynostosis. Oligonucleotide-based array comparative genomic hybridization revealed a -4.79-Mb deletion of 3p26.2 --> pter encompassing CHL1 and CNTN4, and a -19.56-Mb duplication of 5q34 --> qter encompassing MSX2, NKX2-5 and NSD1. The karyotype of the girl was 46,XX,der(3)t(3;5)(p26.2;q34) pat. The present case adds distal 5q duplication to the list of chromosome aberrations associated with coarctation of the aorta.

Phenotypic features of pure 9p deletion in a male infant include cryptorchidism, congenital heart defects and postaxial polydactyly.

We report a 2 1/2-year-old male infant with a karyotype of 46,XY,del(9)(p22) and the phenotypic features of craniofacial dysmorphisms, hypotonia, psychomotor developmental delay, mental retardation, ventricular septal defect, atrial septal defect, cryptorchidism and postaxial polydactyly of the fingers. A rudimentary poorly developed extra digit in the ulnar side of the fifth finger was observed in each hand. The present case adds to the literature of postaxial hexadactyly of the fingers in chromosome 9p deletion syndrome. We suggest that 9pter-p22 may contain genetic loci associated with human postaxial polydactyly.

Partial monosomy 9p (9p22.2-->pter) and partial trisomy 18q (18q21.32-->qter) in a female infant with anorectal malformations.

We report a female infant with a karyotype of 46,XX,der(9)t(9;18)(p22.2;q21.32)pat and the phenotypic features of craniofacial dysmorphisms, developmental delay, hypotonia, horizontal nystagmus, strabismus, congenital heart defects, clubfoot, and anorectal malformations with an anterior ectopic anus and a stenosed anal opening. Array comparative genomic hybridization revealed a 16.93-Mb deletion at 9p24.3-p22.2 encompassing the FREM1 gene and a 20.43-Mb duplication at 18q21.32-q23 encompassing the PIGN gene. We speculate that dual genome imbalances in FREMI at 9p22.3 and in PIGN at 18q21.3 are most likely responsible for the abnormal development of anorectum in this patient.

Pure distal 9p deletion in a female infant with cerebral palsy.

We report cytogenetic and molecular characterization of a 15.63-Mb pure distal deletion of chromosome 9p (9p22.3-->pter) in a l 1/2-year-old female infant with cerebral palsy and diffuse cerebral dysfunction. The deletion is of paternal origin and encompasses the genes of ANKRDS15, DOCK8, FOXD4 and VLDLR. We discuss the genotype-phenotype correlation in this case with neurological dysfunction and a distal 9p deletion of paternal origin.

Pure distal 11q deletion without additional genomic imbalances in a female infant with Jacobsen syndrome and a de novo unbalanced reciprocal translocation.

We report a neonate with pure deletion of distal 11q (11q23.3-->qter) and Jacobsen syndrome. The patient had growth restriction, petechiae, thrombocytopenia, dilation of renal pelvis, congenital heart defects, and seizures. Array comparative genomic hybridization revealed a 15.8-Mb deletion from 11q23.3 to 11q25 without genomic imbalances in other chromosomes. Cytogenetic analysis revealed a karyotype of 46,XX,der(7)(7pter-->7q32),der(11)(11pter--> 11q23.3::7q32-->7qter). The parental karyotypes were normal. This is the first report of pure distal 11q deletion without additional genomic imbalances in a patient with Jacobsen syndrome and a de novo unbalanced reciprocal translocation.

Partial trisomy 1q (1q42.13-->qter) and partial monosomy 6q (6q27-->qter) in a girl with single median maxillary central incisor, corpus callosum dysgenesis and developmental delay.

A 3-year-old girl presented with mental retardation, developmental delay, seizures, hypotonia, brachycephaly, a triangular face, single median maxillary central incisor (SMMCI), prominent forehead, down-slanting palpebral fissures, hypertelorism, a high-arched palate, micrognathia and low-set ears. Computed tomographic scans revealed corpus callosum dysgenesis and hypoplasia of bilateral frontal sinuses. Oligonucleotide-based array comparative genomic hybridization analysis revealed a -20.7-Mb duplication of 1q42.13-->qter and a -3.6-Mb deletion of 6q27-->qter. The karyotype of the girl was 46,XX,der(6)t(1;6)(q42.13;q27)pat. Mutational analysis of the patient revealed no mutation in the genes of SHH, SIX3 and TGIF. The present case adds unbalanced chromosome aberration of partial trisomy 1q and partial monosomy 6q to the list of genetic conditions associated with SMMCI.

De novo satellited 2q associated with corpus callosum dysgenesis, short stature, mental retardation and developmental delay.

We report the cytogenetic and molecular characterization of a 9.46-Mb terminal deletion of 2q in a 3-year-old girl with a de novo satellited 2q (2qs), corpus callosum dysgenesis, short stature, mental retardation and developmental delay. We speculate that haploinsufficiency of HDAC4 is responsible for short stature, mental retardation and developmental delay, and haploinsufficiency of EFHD1 is most likely responsible for the phenotype of corpus callosum dysgenesis in this patient.

Increased risk of cardiovascular disease in Type 1 diabetes: arterial exposure to remnant lipoproteins leads to enhanced deposition of cholesterol and binding to glycated extracellular matrix proteoglycans.

AIMS: To determine fasting and postprandial metabolism of apolipoprotein B48 (apoB48) remnant lipoproteins in subjects with Type 1 diabetes and the relationship to progressive cardiovascular disease, and to investigate the impact of remnant lipoprotein cholesterol accumulation associated with arterial wall biglycan using a rodent model of Type 1 diabetes. METHODS: Normolipidaemic subjects (n = 9) with long-standing Type 1 diabetes (and advanced cardiovascular disease) and seven healthy control subjects were studied. Fasting and postprandial apoB48 concentration was determined following a sequential meal challenge. A rodent model of streptozotocin-induced diabetes was used to investigate the ex vivo retention of fluorescent-conjugated remnants. Binding of remnant lipoproteins to human recombinant biglycan was assessed in vitro. RESULTS: A significantly higher concentration of fasting plasma apoB48 remnants was observed in patients with Type 1 diabetes compared with control subjects. Patients with Type 1 diabetes exhibited a greater total plasma apoB48 area under the curve (AUC) and an increased incremental AUC following a second sequential meal compared with control subjects. The arterial retention of remnants ex vivo and associated cholesterol was increased sevenfold in Type 1 diabetes rats relative to controls. Remnants were shown to bind with significant affinity to human biglycan in vitro and a further 2.3-fold increased binding capacity was observed with glycated biglycan. Remnants were shown to colocalize with both arterial biglycan and glycated matrix proteins in the Type 1 diabetes rodent model. CONCLUSION: Impaired metabolism of remnant lipoproteins associated with enhanced binding to proteoglycans appears to contribute to the arterial cholesterol deposition in Type 1 diabetes. Our findings support the hypothesis that impaired remnant metabolism may contribute to accelerated progression of atherosclerosis in the hyperglycaemic and insulin-deficient state.

Allograft entrapment after lung transplantation: a simple solution using a pleurocutaneous catheter.

BACKGROUND: Chronic pleural effusion following lung transplantation (LTx) is often responsible for respiratory insufficiency and can lead to lung entrapment. Decortication carries considerable morbidity, and extended use of tube thoracostomy is not practical. We have utilized an indwelling pleurocutaneous catheter in the setting of intractable post-transplant effusion and have reviewed our experience to determine whether this strategy: 1) facilitates resolution of effusion, and 2) adequately palliates lung entrapment. METHODS: Twelve PleurX (Denver Biomedical, Golden, CO, USA) catheters were placed in 9 LTx patients (6 unilateral, 3 bilateral) for refractory pleural effusions after standard tube thoracostomy drainage failed (12/12). Two-thirds of the patients (8/12) also had concomitant lung entrapment. RESULTS: There was no operative mortality. Median time from LTx to catheter placement was 79 days (range 21-769). Catheter use achieved the desired outcome in 11/12 placements. Catheters remained in place for a median of 86 days (range 35-190). Direct catheter-related complications included hemothorax (1) and empyema (1). CONCLUSION: Use of an indwelling pleurocutaneous catheter effectively achieves its intended goals of pleurodesis and management of entrapped lungs after LTx.

The effect of recipient hepatitis C virus infection on outcomes following heart transplantation.

BACKGROUND: Insufficient data exist on the clinical course of hepatitis C virus (HCV) infection in heart transplant (HT) recipients. Our study reports the outcomes of heart transplantation in pretransplantation HCV-positive (HCV+) recipients. METHODS: A retrospective analysis of the heart transplantation database at our institution was performed to identify HT recipients who were HCV+ prior to transplantation. Chart reviews yielded demographic features, liver function tests, graft function, incidence of posttransplantation acute hepatitis and transplant coronary artery disease, and patient survival data. RESULTS: Between 1995 and 2006, 10 HCV+ patients underwent cardiac transplantation. The recipient mean age was 47 years (range, 23-69). Seven recipients were males and 3 were females. At listing 9 patients had no cirrhosis. One patient with Child-B cirrhosis was listed for combined heart-liver transplantation. Two of 10 donors were known to be HCV carriers. Posttransplantation in-hospital survival rate was 100%. At a mean follow-up of 58 months (range, 1.6-145), 3 deaths occurred, yielding an overall survival rate of 70%. Only 1 death (10%) was linked to accelerated acute hepatitis. Transplant coronary artery disease was detected in 2 patients (20%). Echocardiograms of survivors at last follow-up revealed normal ejection fractions. In addition, there were no cases of hepatocellular carcinoma; all survivors were without evidence of hepatic dysfunction. CONCLUSIONS: Transplanting recipients known to have HCV did not seem to affect overall posttransplantation survival or to increase the risk of liver dysfunction or graft-related complications.

Open window thoracostomy: modern update of an ancient operation.

INTRODUCTION: In modern day thoracic surgical practice, better understanding of the pathophysiology of intrathoracic infections, improved antibiotic therapy and advancements in thoracic surgical techniques have decreased the use of procedures such as open window thoracostomy (OWT). Despite this, there are occasions where OWT cannot be avoided, and it is of interest where its current utility lies. To determine the current efficacy of OWT, we reviewed our recent experience with a focus on the indications, timing of surgery, effectiveness in clearing infection, patient survival, and timing of closure. METHODS: After Institutional Review Board approval, charts of 78 patients were reviewed. Dates reviewed were from 1/1/1998 to 1/1/2008. Patients were predominantly male (66 %) with a median age 58 years. Median time from initial diagnosis to OWT was 70 days (range 1 to 720 days). RESULTS: Primary indication for surgery was empyema in 75 (96 %), and most patients had previous thoracic surgery. The most frequent causes of empyema were post-pneumonectomy (n = 25), post-pneumonic (n = 14), and post-lobectomy (n = 9). Bronchopleural fistulae were present in 29 (37 %) cases. Lung cancer was diagnosed in 34 (45 %) patients, and 24 underwent perioperative radiation therapy. Patient survival at 1 month, 6 months, 1 year and 5 years was 94 %, 82 %, 74 % and 60 %, respectively, with an in-hospital mortality of 6.4 %. Infection was controlled in nearly all patients (n = 72). Fifteen (19 %) patients underwent surgical closure for OWT; in 2 (2.6 %), OWT closed spontaneously. CONCLUSIONS: Currently, open window thoracostomy is used to treat complex empyema incurred from pulmonary resection, cancer and/or infection in patients that cannot be managed by more conservative strategies. Overall mortality and morbidity rates are acceptable in this debilitated patient group.

Methods to assess impaired post-prandial metabolism and the impact for early detection of cardiovascular disease risk.

Post-prandial lipaemia has emerged as a key contributor to cardiovascular disease (CVD) risk and progression. Specifically, delayed clearance of chylomicrons (CM) and their remnants increase the delivery of triglyceride and cholesteryl ester to the vessel wall and can accelerate the progression of atherosclerosis, which may be particularly pertinent to individuals with insulin resistance and/or obesity. As the number of studies linking post-prandial metabolism and chronic disease increases, interest has grown in the use of parameters reflecting CM metabolism as a possible indicator of early CVD risk. This, in turn has raised the question of what method might be most appropriate to detect CM and their remnants in plasma accurately. However, the handful of techniques able to measure CM metabolism (triglyceride-rich lipoprotein fractions; remnant-lipoprotein cholesterol; retinyl esters, CM-like emulsion; sodium dodecyl sulphate-polyacrylamide gel electrophoresis; immunoblotting, enzyme-linked immunoabsorbent assays; C(13) breath test; capillary finger prick) differ in their specificity, cost and applicability in research and in the clinical setting. In this review, we explore the scientific and clinical implications of CM methodology to better understand early risk assessment of CVD. We raise ongoing issues of the need to appreciate differential separation of very low-density lipoprotein and CM fractions, as well as to identify the technical basis for imprecision between assays for apolipoprotein B48. We also highlight emerging issues with respect to the practicality of measuring post-prandial metabolism in large clinical studies and offer opinions on the appropriateness of existing techniques in this field.

Resection of a giant malignant mediastinal peripheral nerve sheath tumour under cardiopulmonary bypass.

Malignant peripheral nerve sheath tumour (MPNST) is a rare occurrence in the mediastinum. It is biologically aggressive and is generally resistant to chemoradiation therapy. The mainstay of treatment is complete surgical resection. We report a large MPNST which invaded into the adjacent aortic wall in a 50-year-old man. Extensive resection, which included aortic reconstruction under cardiopulmonary bypass and deep hypothermic arrest, was necessary for a good long-term outcome.

Cogan's syndrome with recurrent carotid and aortic aneurysms: a potentially fatal disorder mimicking Marfan syndrome.

Cogan's syndrome (CS) is a rare multisystemic disease characterized by vestibuloauditory dysfunction, inflammatory eye disease and vasculitis. Aortic aneurysms due to aortitis are under-recognized in CS, and are potentially fatal, with two of eight reported cases dying from aneurysm/arterial rupture. The presence of aneurysms was not recognized antemortem in both cases, highlighting the importance of early detection to prevent this potentially fatal outcome. We report a 17-year-old Chinese male with recurrent carotid and aortic aneurysms, bilateral sensorineural hearing loss, and recurrent scleritis who was initially thought to have Marfan syndrome. The diagnosis of CS was made 4.5 years after initial presentation, during which time recurrent aneurysms due to active aortitis (with aneurysmal rupture on one occasion) necessitated four surgical procedures. Treatment with methotrexate and corticosteroids resulted in no recurrence of aneurysms over 2 years of follow-up. This case illustrates (i) the challenges in diagnosing CS when various manifestations occur separately over a relatively long time period, (ii) that detection of aortic aneurysms in young patients, especially if recurrent, should prompt investigations for vasculitis/aortitis to prevent potentially fatal aneurysm rupture, and (iii) that methotrexate and high-dose corticosteroids may be effective in preventing development of further aneurysms in CS patients.

Bilateral pneumothoraces as a complication of acupuncture.

Pneumothorax developing secondary to acupuncture is rare. However, in an undiagnosed case, it may cause fatality. The real incidence of acupuncture-related pneumothorax is not known but is acknowledged to be underdiagnosed and under-reported. We describe pneumothorax occurring in a 52-year-old woman who developed bilateral pneumothoraces, with one side being a tension pneumothorax, immediately following acupuncture. The needle was inserted at a paravertebral point at the level of the third vertebral spinous process.