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Publications and source records attributed to I Bar.

33 records · Page 2Linked to original sources
PubMed1996

[Successful single-lung transplantation in emphysema].

Lung transplantation is now considered acceptable therapy for end-stage lung disease. Until recently therapy for emphysema was disappointing, but lung transplantation has brought new hope for those terminally ill with the disease. We present our early experience with single-lung transplantation in 5 men and 1 woman with emphysema, 40-61 years old. All recovered following surgery, with remarkable improvement in lung function and functional capacity. They are now 6-20 months post-transplantation, do not need oxygen supplementation and are able to perform their normal daily activities. Shortage of donor organs is the limiting factor for single-lung transplantation in these patients.

Adult↗
PubMed1996

Spectroscopy of D2O (2,0,1)

The (2,0,1) <-- (0,0,0) rovibrational transitions of D2O in the near infrared region were measured with a resolution of 0.07 cm-1 using photoacoustic laser absorption spectroscopy. We report on the assignment of newly observed transitions and determine new inertial and centrifugal constants of D2O (2,0,1) using the Watson-type A-reduced Hamiltonian for asymmetric tops.

Journal Article↗
PubMed1995

Efficient high-resolution genetic mapping of mouse interspersed repetitive sequence PCR products, toward integrated genetic and physical mapping of the mouse genome.

The ability to carry out high-resolution genetic mapping at high throughput in the mouse is a critical rate-limiting step in the generation of genetically anchored contigs in physical mapping projects and the mapping of genetic loci for complex traits. To address this need, we have developed an efficient, high-resolution, large-scale genome mapping system. This system is based on the identification of polymorphic DNA sites between mouse strains by using interspersed repetitive sequence (IRS) PCR. Individual cloned IRS PCR products are hybridized to a DNA array of IRS PCR products derived from the DNA of individual mice segregating DNA sequences from the two parent strains. Since gel electrophoresis is not required, large numbers of samples can be genotyped in parallel. By using this approach, we have mapped > 450 polymorphic probes with filters containing the DNA of up to 517 backcross mice, potentially allowing resolution of 0.14 centimorgan. This approach also carries the potential for a high degree of efficiency in the integration of physical and genetic maps, since pooled DNAs representing libraries of yeast artificial chromosomes or other physical representations of the mouse genome can be addressed by hybridization of filter representations of the IRS PCR products of such libraries.

Animals↗
PubMed1995

A YAC contig containing the reeler locus with preliminary characterization of candidate gene fragments.

The reeler mutation in the mouse maps to proximal chromosome 5 and defines a key gene involved in brain development and evolution. No gene product is known, and the locus is currently being characterized by positional cloning. YAC clones corresponding to the closest markers D5Mit61 and D5Mit72 have been isolated. Cloned extremities of the YAC inserts were used to construct a 1.1-Mb contig, a 700-kb fragment of which was shown to contain the reeler locus. The integrity of the contig was verified by physical mapping on genomic DNA. The classical allele of the reeler mutation was associated with a 150-kb deletion between D5Mit61 and D5Mit72, while no gross chromosomal anomaly was found in the Orleans allele. Candidate coding sequences were isolated to construct a preliminary transcriptional map of the reeler region. Cosmid clones mapping within the rl deletion revealed a large transcript of more than 11 kb, which was present in normal embryonic brain but barely detectable in homozygous rlOrl/rlOrl embryonic brain, suggesting strongly that it corresponds to the reeler transcript.

Animals↗
PubMed1995

Effects of magnesium on myocardial function after coronary artery bypass grafting.

The effects of perioperative administration of magnesium sulfate on myocardial function was studied in patients with unstable angina (grade IV) undergoing coronary artery bypass grafting. Myocardial protection consisted of antegrade and retrograde continuous warm blood cardioplegia. Patients were randomly divided into two groups. Group A (50 patients) received intravenous magnesium sulfate (16 mmol) continuously from the time of anesthetic induction to aortic cross-clamping and a second dose (32 mmol) starting after the release of aortic cross-clamp until 24 hours later. Group B (48 patients) did not receive magnesium sulfate and served as control. Left ventricular stroke work index increased in group A from 34 +/- 3 g.m/m2 before operation to 42 +/- 3 g.m/m2, 45 +/- 2 g.m/m2, and 47 +/- 2 g.m/m2, 1, 6, and 12 hours after operation, respectively (p < 0.05 versus preoperative), and in group B from 33 +/- 3 g.m/m2 before operation to 38 +/- 3 g.m/m2, 40 +/- 2 g.m/m2, and 41 +/- 2 g.m/m2, 1, 6, and 12 hours after operation, respectively (p < 0.05). Left ventricular stroke work index was higher in group A 6 (p = 0.06), 12, and 24 hours (p < 0.05) after operation compared with group B. The incidence of ventricular arrhythmias requiring treatment was significantly higher (p < 0.05) in group B: 14 patients versus 1 patient in group A. Postoperative hypertension was more frequent in group B: 16 patients versus 2 patients in group A (p < 0.05). These results indicate that perioperative administration of magnesium sulfate may contribute to better myocardial recovery and fewer ventricular tachyarrhythmias after operation.

Adult↗
PubMed1994

A high-resolution genetic map of mouse chromosome 5 encompassing the reeler (rl) locus.

Using interspecific crosses between BALB/c and Mus spretus (SEG) mice, the murine reeler (rl) gene was mapped to the proximal region of chromosome 5 between the hepatocyte growth factor gene (Hgf) and the D5Mit66 microsatellite. The following order was defined: (centromere)-Cchl2a/Hgf-D5Mit1-D5Nam1/D5-Nam2 -rl/D5Mit61-D5Mit72-Xmv45-Htr5a- Peplb-D5Nam3-D5Mit66. Estimated distances between reeler and the nearest flanking markers D5Nam1 and D5Mit72 are 1.5 and 1.0 cM, respectively (95% confidence level), suggesting that the region could be physically mapped using a manageable number of YAC clones.

Alleles↗
PubMed1992

Covalent binding of 3'-O-(4-benzoyl)benzoyl adenosine 5'-triphosphate (BzATP) to the isolated alpha and beta subunits and the alpha 3 beta 3 core complex of TF1. Covalent binding of BzATP prevents association of alpha and beta subunits and induces dissociation of the alpha 3 beta 3 core complex.

Binding of the photoreactive ATP analog, 3'-O-(4-benzoyl)benzoyl adenosine 5'-triphosphate (BzATP), to the isolated alpha and beta subunits of TF1 and to the alpha 3 beta 3 "core" complex of the holoenzyme is described. About 1 mol of BzATP/mol of subunit was incorporated to isolated alpha and beta subunits. The incorporation of BzATP was prevented by ATP. Covalent binding of BzATP to the alpha subunit was in general somewhat lower than that observed with the beta subunit. No complex was formed upon mixing of either of the modified subunits with the complementary nontreated subunits. Covalent binding of 3 mol of BzATP/alpha 3 beta 3 complex completely inhibited ATPase activity and resulted in the dissociation of the complex. The labeled nucleotide analog was specifically incorporated into the beta subunit of the complex. The holoenzyme TF1, in contrast to the core complex, did not dissociate to the individual subunits upon covalent binding of BzATP. These results are discussed in relation to the location of the catalytic nucleotide binding site(s) and the conformation stability of the alpha 3 beta 3 core complex of TF1.

Adenosine Triphosphate↗
PubMed1992

Serum levels of IL-1, IL-6 and tumour necrosis factors in patients undergoing coronary artery bypass grafts or cholecystectomy.

Plasma levels of biologically active IL-1, tumour necrosis factor (TNF) and IL-6 were measured before, during and after coronary artery bypass graftings (CABG) (n = 9) and cholecystectomy (CHO, n = 9), and in normal controls (nine healthy volunteers). Mean pre-operative IL-1 concentration in four of the nine CABG patients was 0.452 + 0.03 ng/ml, significantly (P less than 0.001) higher than that of the other five (0.045 +/- 0.009 ng/ml), CHO patients (0.035 +/- 0.005 ng/ml) and controls (0.029 +/- 0.008 ng/ml). Three of the four patients with high pre-operative IL-1 had functional capacity IV, while the other five had functional capacity IIa or IIb. Slight IL-1 elevation after anaesthesia, followed by reduction after initiation of bypass, elevation on completion of surgery and reduction to basal levels after 7 days was found in patients undergoing CABG. Mean basal TNF levels of CABG and CHO patients did not differ, but were higher than those of controls (2.85 +/- 0.5 ng/ml for CABG, 2.05 +/- 0.06 ng/ml for CHO, 0.72 +/- 0.07 ng/ml for normals, P less than 0.001). A unique kinetics of release during CABG was observed also for TNF. Mean pre-operative IL-6 levels were normal (50 +/- 3 ng/ml for CABG, 50 +/- 0.5 ng/ml for CHO and 65 +/- 10 ng/ml for controls). Gradual elevation to a mean peak of 725 +/- 100 ng/ml on completion of CABG was observed as compared with 275 +/- 50 ng/ml in CHO (P less than 0.01). On the seventh post-operative day mean IL-6 levels returned to normal. Two patients with post-operative low-grade fever (38 degrees C) had high, late cytokine levels. One of these two patients had leucocytosis, sterile discharge from the operative wound and was diagnosed as suffering from the Dressler syndrome. In this study elevated cytokine values and unique kinetics of release into the serum were found in patients undergoing CABG.

Adult↗
PubMed1989

[Autotransfusion of shed mediastinal blood after cardiac surgery].

We have developed a technique for autotransfusion of shed mediastinal blood collected in the cardiotomy reservoir. Results in the first 50 consecutive patients in whom the system was employed were studied prospectively (group A) and were compared with those of the last 50 consecutive patients operated on before application of the new method (group B). The mean preoperative hematocrit (about 42%) and the total postoperative bleeding (about 11) were similar in both groups. Only 24 patients (48%) in group A required homologous blood transfusion, versus 43 (86%) in group B (p = 0.0001). This resulted in a 57% saving of blood units in group A (mean, 1.16 +/- 1.49 units per patient versus 2.72 +/- 1.99 in group B, p less than 0.0001). Foreign blood transfusion was thus avoided in 21 of the last 25 patients (84%) of group A. 7 days after operation, the mean hematocrit in group A was 30.9 +/- 4.3, compared with 33.0 +/- 3.8 in group B (p less than 0.001). Hemolytic jaundice occurred in 7 group B patients (14%) but in none in group A (p less than 0.01). A trend towards reduction in other complications was also demonstrated. We conclude that the use of foreign blood transfusions in those undergoing open heart surgery can be reduced significantly by this method, thus avoiding immediate transfusion reactions and minimizing the risks of late complications.

Anemia, Hemolytic↗
PubMed1989

Laser photobleaching leads to a fluorescence grade adenosine deaminase.

The enzyme adenosine deaminase (adenosine aminohydrolase EC 3.5.4.4) from calf intestinal mucosa is commercially available at high purity grade yet, at the sensitivity at which fluorescence studies may be undertaken, a nonpeptidic fluorescence is detectable at lambda exmax = 350 nm and lambda emmax = 420 nm. A sevenfold decrease of this nonpeptidic fluorescence was obtained upon irradiation by the third harmonic (355 nm) of a Nd:YAG laser for 16 min, at 5 mJ/pulse, with a pulse width of 6 ns at a repetition rate of 10 Hz. The decline of fluorescence was accompanied by a negligible loss of enzymatic activity. Moreover, the integrity of the protein was ascertained by (i) its fluorescence (lambda exmax = 305 nm, lambda emmax = 335 nm) and lifetime distribution and (ii) its kinetics in the presence of the substrate adenosine and two inhibitors, all of which remained essentially unaltered. Laser photobleaching is a simple way to achieve a fluorescence grade adenosine deaminase.

Adenine↗
PubMed1986

The value of ultrasonographic endometrial measurement in the prediction of pregnancy following in vitro fertilization.

This work was undertaken for evaluation of the value of endometrial thickness as an early predictor for the success of in vitro fertilization (IVF). Endometrial changes were evaluated ultrasonographically in 47 women undergoing IVF. A high-dose gonadotropin protocol was used for induction of multiple follicular development. Thirty-seven women did not conceive following the procedure (group I), and 10 conceived (group II). Ultrasonographic endometrial measurements were performed repeatedly throughout the cycle. Serum 17 beta-estradiol and progesterone levels were evaluated concomitantly. Three consecutive growth patterns of the endometrium were observed. The first was a rapid one with a daily growth rate of about 0.5 mm from approximately 9 mm on day -3 to 12 mm on day +2 (day 0 being the day of human chorionic gonadotropin administration). The second phase, following follicular aspiration, showed a decrease in growth rate to about 0.1 mm per day until day +11, when a thickness of about 13 mm was measured. In group I growth was arrested from day +11 until menstruation, whereas in group II an accelerated growth rate of about 0.4 mm per day could be demonstrated from day +14 onward. Endometrial growth did not correlate with serum estradiol or progesterone levels. No conception occurred with an endometrial thickness below 13 mm on day +11. It is concluded that endometrial thickness follows a distinct pattern of growth in human menopausal gonadotropin-induced cycles and does not correlate with serum sex hormones.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Ultrasonically guided oocyte collection under local anesthesia: the first choice method for in vitro fertilization--a comparative study with laparoscopy.

Ultrasonically guided oocyte collection gradually replaces laparoscopy in many in vitro fertilization (IVF) centers. In the present study we compare the efficacy of both methods in our IVF program. One hundred twenty patients were prospectively randomized into two groups. Sixty women underwent oocyte collection during laparoscopy under general anesthesia, and 60 women under ultrasound guidance with local anesthesia. Superovulation was induced with human menopausal gonadotropin/human chorionic gonadotropin. For the oocyte collection a cannula with a trocar was used for single percutaneous puncture, through which both ovaries could be reached by the aspiration needle. The number of aspirated oocytes and transferred embryos was higher in the laparoscopy group as compared with the ultrasound group (5.3 versus 4.0 per woman and 3.0 versus 2.3 per woman, respectively); but the clinical pregnancy rate per cycle was similar in both groups (12.5% versus 14.5%). Ultrasound aspiration seems to be as effective as laparoscopy in terms of oocyte retrieval and conception rates. Because the procedure is simple and inexpensive, we believe that it may replace laparoscopy as a method for oocyte collection in most patients who undergo IVF.

Adult↗
PubMed1985

Conformational polymorphism VI: the crystal and molecular structures of form II, form III, and form V of 4-amino-N-2-pyridinylbenzenesulfonamide (sulfapyridine).

The crystal structures of three crystalline forms of 4-amino-N-pyridinylbenzenesulfonamide (sulfapyridine) have been determined by X-ray single crystal structure analysis. Form II crystallizes in space group P2(1)/c with four molecules in the unit cell: a = 0.6722(1) nm, b = 2.0593(5) nm, c = 0.8505(1) nm, beta = 101.14(1) degrees; Form III crystallizes in space group C2/c with eight molecules in the unit cell: a = 1.2830(2) nm, b = 1.1714(3) nm, c = 1.5400(3) nm, beta = 94.12(1) degrees; Form V crystallizes in the orthorhombic space group Pbca with 16 molecules in the unit cell: a = 2.4722(10) nm, b = 1.5710(15) nm, c = 1.2147(7) nm. The three structures were solved by direct methods and refined anisotropically to R factors of 0.045, 0.052, and 0.063, respectively. Bond lengths and bond angles agree well among the molecules in these structures; however, the system exhibits conformational polymorphism since the molecular conformation, as measured by torsion angles, differs significantly among the three forms. Sulfapyridine exhibits the imide configuration in all three structures rather than the amide form present in other sulfonamide compounds. Using the structural data, the powder patterns of the three forms have been computer generated to provide standard diffraction patterns for comparison with the variety of polymorphic forms reported in the literature.

Chemical Phenomena↗