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We present an interesting case illustrating the possible hemodynamic consequences when a left-sided arteriovenous hemodialysis fistula is combined with the congenital anomaly of a persistent left superior vena cava (PLSVC). Our case illustrates the importance of an echocardiographic examination with attention to the coronary sinus (CS) caliber-raising suspicion of a PLSVC-in the assessment for the hemodialysis access in end-stage renal disease patients. The causes and symptoms of CS dilatation, as well as the literature on PLSVC, are also discussed in detail., (© 2012 Wiley Periodicals, Inc.)

On the basis of a combination of new structural data (eleven single-crystal structure determinations are presented) and information from the Cambridge Structural Database, it has been shown that self-complementary hydrogen-bond based amide...amide dimers can be relied upon as effective supramolecular synthons for the assembly and organization of acac- and paddle-wheel complexes of a variety of metal(II) ions. The targeted molecular recognition event and intended extended one-dimensional motif appear with a supramolecular yield of 78% (a total of 28 structures were examined). Despite the fact that the hydrogen bonds that give rise to the R2(2)(8) motif can be disrupted by both carboxylate- and acac-ligands, as well as by solvent molecules, they remain remarkably resilient and therefore represent useful synthetic tools in inorganic crystal engineering.

New neurons are added to the forebrain song control regions high vocal center (HVC) and Area X of juvenile songbirds but the identity and site of origin of these cells have not been fully characterized. We used oncoretroviral vectors to genetically label neuronal progenitors in different regions of the zebra finch lateral ventricle. A region corresponding to the mammalian medial and lateral ganglionic eminences generated medium spiny neurons found in Area X and in the striatum surrounding Area X, and at least two classes of interneurons found in HVC. In addition, our experiments indicate that the HVC projection neurons that project into nucleus robust nucleus of the arcopallium (RA) are born locally from the ventricular region immediately dorsal to HVC. The ability to genetically target neuron subpopulations that give rise to different song system cell types provides a tool for specific genetic manipulations of these cell types. In addition, our results suggest striking similarities between neurogenesis in the embryonic mammalian brain and in the brain of the juvenile songbird and provide further evidence for the existence of conserved cell types in the forebrain for birds and mammals.

Immobilized DNA hairpins are exploited in a novel approach to assay DNA ligases and nucleases. A fundamental characteristic of the assay is that a fluorophore at the remote terminus of the hairpin reports on the integrity of the DNA backbone. The functionality of the protocol is confirmed using ATP- and NAD+-dependent DNA ligases and the nicking enzyme N.BbvCIA. The assay format is amenable to high-throughput analysis and quantitation of enzyme activity, and it is shown to be in excellent agreement with the more laborious electrophoretic approaches that are widely used for such analyses. Significantly, the assay is used to demonstrate sequential breaking and rejoining of a specific nucleic acid. Thus, a simple platform for biochemically innovative studies of pathways in cellular nucleic acid metabolism is demonstrated.

Birds are of great interest for a variety of research purposes, and effective methods for manipulating the avian genome would greatly accelerate progress in fields that rely on birds as model systems for biological research, such as developmental biology and behavioral neurobiology. Here, we describe a simple and effective method for producing transgenic birds. We used lentiviral vectors to produce transgenic quails that express GFP driven by the human synapsin gene I promoter. Expression of GFP was specific to neurons and consistent across multiple generations. Expression was sufficient to allow visualization of individual axons and dendrites of neurons in vivo by intrinsic GFP fluorescence. Tissue-specific transgene expression at high levels provides a powerful tool for biological research and opens new avenues for genetic manipulation in birds.

Lymphocyte costimulation via the inducible costimulatory molecule (ICOS) is required for effective humoral immunity development. Following immunization with Torpedo acetylcholine receptor (AChR), ICOS gene knockout (KO) mice were highly resistant to clinical experimental autoimmune myasthenia gravis (EAMG) development, had less serum AChR-specific immunoglobulins (Igs), and exhibited a diminutive germinal center (GC) reaction in secondary lymphoid tissues. Lymphocyte proliferation and both Th1 and Th2 differentiation in response to AChR and the AChR dominant alpha146-162 peptide were inhibited by the ICOS gene deficiency. ICOS-mediated lymphocyte costimulation is thus vital to the induction of T cell-mediated humoral immunity to AChR and the development of clinical EAMG.

Background: In patients with end-stage renal disease (ESRD), treated with haemodialysis, a high overall mortality is observed. A previous study showed that cardiac troponin T (cTnT) is a strong independent predictor of outcome in this population. In this study we investigated possible causes of cTnT increase and its relationship with a marker of oxidative stress., Methods: In a group of 71 haemodialysis patients (36 male, 35 female, mean age 68.7+/-1.5 years) we determined cTnT and compared its presence with several biochemical parameters and with malondialdehyde (MDA), which is an indicator of oxidative stress. None of the patients suffered an acute coronary event during the observation period. Three measurements of cTnT and MDA were performed with a 2-week interval. Forty-nine patients underwent a transthoracic echocardiography., Results: Twenty-nine patients (or 40.8%) had a positive cTnT determination (defined as cTnT >/=0.10 ng/ml). cTnT positive patients had significantly higher levels of MDA (P=0.0125), C-reactive protein (CRP) (P=0.04) and pre-dialysis urea (P=0.04). Regression analysis showed that both pre-dialysis urea and MDA independently influenced cTnT. No correlation was found with age, dialysis adequacy, post-dialysis urea, total cholesterol, white blood cell count, fibrinogen or any of the echocardiographical parameters. Presence of heart failure, diabetes or use of medication could not discriminate between cTnT positive and cTnT negative patients. MDA levels correlated positively with time on haemodialysis (P=0.0021). Echocardiography showed left ventricular hypertrophy in 88% of the examined patients and impaired wall motion in 35%. Patients with clinical signs of heart failure had a lower ejection fraction and worse wall motion score index. No correlation existed between echocardiographic findings and cTnT or MDA. Survival was independently predicted by cTnT (P=0.0025), MDA (P=0.0007), CRP (P=0.006) and age (P=0.0143). Patients with both cTnT and CRP increase had a survival of <50% at 1 year, compared with 90% in patients with both cTnT and CRP within the normal range and 80% when either CRP or cTnT was increased (chi(2)=12.127; P=0.0023)., Conclusions: This study confirms that the presence of cTnT predicts prognosis in ESRD. The presence of cTnT is linked to oxidative stress, inflammation and uraemia. The absence of specific findings on EKG and echocardiography points towards subclinical myocardial damage caused by endothelial disturbances.