A new radiolabeled, bifunctional photoaffinity cross-linking reagent, N-succinimidyl p-benzoyl-[2,3-3H2]dihydrocinnamate, has been synthesized in high yield and with high specific activity. This reagent can be used to append the benzophenone photophore to amino groups of small molecules, such as O-aminoalkylinositol polyphosphates and polypeptides. The resulting tritiated photoaffinity labels can be purified and manipulated in ambient light and can be activated at 360 nm.

Affinity Labels↗

PubMedDate not supplied

Doppler study on pulmonary venous flow in the human fetus.

OBJECTIVES: The fetal pulmonary circulation is different from the postnatal circulation: the flow is small. The arterial pressure is almost systemic, and the vascular resistance is high. Moreover, lungs are collapsed in the fetus. However, the pulmonary venous flow in the fetus has not been studied. The aims of this study were to look at flow patterns of pulmonary venous system in the fetus and to see whether there are any changes in Doppler parameters with fetal growth. METHODS: The pulmonary venous flow velocity was analyzed in 56 normal human fetuses. The fetal gestational age ranged from 17 to 37 weeks. Pulsed-Doppler echocardiography was used to investigate the right upper pulmonary vein in four-chamber view. After the pulmonary venous signal was obtained, by enlarging the sample size, the pulmonary arterial signal was superimposed for timing. Heart rate velocities at systolic peak (S), at diastolic peak (D), at nadir between S and D (O), and at nadir between D and the next S (X) and velocity-time integral were measured. RESULTS: The pulmonary venous signal showed basically continuous flow from pulmonary vein toward left atrium through all the cardiac cycles, and it had biphasic peaks: one during the systolic and the other during the diastolic phase. The systolic peak of pulmonary vein occurred slightly earlier or later than the systolic upstroke of pulmonary arterial waveforms. The systolic peak of pulmonary vein was higher than the diastolic peak in 45 out of 56 cases. Velocities of systolic and diastolic peaks and velocity-time integral of the pulmonary vein have significantly increased with fetal growth. CONCLUSIONS: In the fetus, the flow pattern of the pulmonary vein was similar to that of the postnatal pattern with the exception of absence of atrial reversal. Lower velocities may reflect a decreased pulmonary flow volume.

Blood Flow Velocity↗

PubMedDate not supplied

Efficient gene transfer and expression in islets by an adenoviral vector that lacks all viral genes.

Although adenoviral vector-mediated gene transfer has significant potential for gene therapy, host immune responses to virally expressed proteins and small insert capacity may limit its clinical application. In order to overcome these disadvantages, a new adenoviral vector that lacks all viral genes has been developed. Using the green fluorescent (GFP) gene as a reporter gene, we investigated the efficiency of gene transfer by this all-viral-genes-deleted and minimal cis-element remaining adenoviral vector (miniAd-GFP) in islets in vitro and ex vivo, and compared it with the E1-deleted adenoviral vector (E1-GFP). One day after in vitro infection, GFP was expressed in both miniAd-GFP- and E1-GFP-infected islets. The percentage of GFP-positive single cells was not significantly different between miniAd-GFP-infected islets and E1-GFP-infected islets. When these islets were transplanted into syngeneic diabetic mice, both miniAd-GFP- and E1-GFP-infected islet grafts reversed diabetes, and normal blood glucose levels were maintained for over 20 weeks posttransplantation. Mild lymphocyte infiltration was found in all E1-GFP-infected islet grafts at all time points. However, this was not seen in most miniAd-GFP-infected islet grafts. Our results indicate that gene transfer by an adenoviral vector that lacks all viral genes is as efficient as E1-deleted adenoviral vector-mediated gene transfer in islets. Furthermore, this adenoviral vector might be less immunogeneic than the E1-deleted adenoviral vector.

Adenoviridae↗

PubMedDate not supplied

Analysis of heterologous and homologous promoters and enhancers in vitro and in vivo by gene transfer into Japanese medaka (Oryzias latipes) Xiphophorus.

Efficient expression systems are required for analysis of gene regulation and function in teleost fish. To develop such systems, a number of inducible or constitutive promoter and enhancer sequences of fish or higher vertebrate origin were tested for activity in a variety of fish cell lines and in embryos of the Japanese medaka fish (Oryzias latipes) and Xiphophorus. The activity of the different promoter-enhancer combinations were quantitated. Considerable differences were found for some constructs if tested in vitro or in vivo. Fro the data obtained, a set of expression vectors for basic research as well as for aquaculture purposes were established.

Animals↗