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Biomedical subjects

A Roth

Publications and source records attributed to A Roth.

At least 19 recordsLinked to original sources
PubMed1995

The DNA binding domain of the initiator protein DnaA.

The 94 C-terminal amino acids of the initiator protein DnaA of Escherichia coli are required and sufficient for specific binding to the cognate DNA binding site. The binding domain contains two potential amphipathic alpha-helices and a third alpha-helix. It represents a new DNA binding motif so far not found in other DNA binding proteins. Temperature-sensitive mutations in the binding motif, dnaA204, dnaA205 and dnaA211, abolish DNA binding. In the solid-phase DNA binding assay, applicable to other DNA binding proteins, fusions of domains of DnaA protein to beta-galactosidase are reacted with biotinylated anti-beta-galactosidase antibody. These are coupled to streptavidin-coated magnetic beads. The DNA binding domain is able to selectively remove the DNA target (oriC) from the liquid phase. Alternatively, the DNA binding domain is fused to a peptide containing a target sequence which is naturally biotinylated in vivo in E.coli. This fusion protein can be coupled directly to streptavidin-coated magnetic beads. Homologies between DnaA protein and transcription factors of the NtrC family are discussed.

Amino Acid Sequence↗
PubMed1995

On-site catheterization laboratory and prognosis after acute myocardial infarction. Israeli Thrombolytic Survey Group.

BACKGROUND: Since the introduction of thrombolytic therapy for patients with acute myocardial infarction, the use of coronary angiography has substantially increased. We sought to determine whether the presence of on-site coronary angiographic facilities influenced the utilization of coronary procedures in patients with acute myocardial infarction hospitalized in Israel's coronary care units. METHODS: A prospective survey was conducted in January and February 1992 in the 25 coronary care units operating in Israel, 15 of which had on-site catheterization facilities. Data on demographics, clinical features, thrombolytic therapy, and the type of coronary diagnostic or therapeutic procedures performed during the current in-hospital stay were recorded. Mortality, both in-hospital and 1 year after discharge, was assessed for all patients in the survey. RESULTS: One thousand fourteen consecutive patients with acute myocardial infarction were hospitalized during the survey, 307 (30%) of whom were admitted to 10 coronary care units without and 707 of whom were treated in hospitals with on-site coronary angiography facilities. Demographic and baseline characteristics were similar in both groups. Thrombolytic therapy was provided equally (46%) to patients admitted to hospital with and without catheterization laboratories. Patients admitted to hospitals with these laboratories underwent coronary angiography (26%) and percutaneous transluminal angioplasty and/or coronary artery bypass grafting (12%) in greater numbers than counterparts admitted to hospitals without such laboratories (10% and 5%, respectively). Hospital and cumulative 1-year mortality rates were 11% and 18%, respectively, in patients admitted to hospitals with on-site catheterization facilities vs 10% and 17%, respectively, in the patient group admitted to the other hospitals. Patients receiving thrombolytic therapy had similar hospital mortality rates unrelated to the availability of coronary catheterization laboratories. CONCLUSION: This national survey showed that the availability of invasive coronary facilities led to increased use of diagnostic and therapeutic coronary procedures among patients with acute myocardial infarction. There was no difference in hospital or 1-year mortality rates in patients admitted to hospitals with or without on-site coronary angiographic facilities.

Aged↗
PubMed1995

Safety of coronary ultrasound angioplasty: effects of sonication on intact canine coronary arteries.

The purpose of this work was to examine in vivo the safety of sonication in the coronary arteries in a live animal model. In intact dogs (n = 8), balloon dilatation was performed on the proximal left anterior descending artery (LAD) followed by sonication to the left circumflex artery (LCX) in power levels found to be optimal for thrombus ablation. Post-dilatation and post-ultrasound coronary angiography, echocardiography, histopathology, CK-MB, indices of hemolysis, and coagulation were compared. Sonication did not induce changes in the ECG or blood pressure. Coronary angiography revealed no adverse side effects or change in arterial diameter (2.3 +/- 0.7 vs. 2.4 +/- 0.3 mm). Echocardiography showed transient opacification of the myocardium. Histopathology revealed a comparable minimal degree of endothelial denudation. After sonication there were no changes in the level of CK-MB (312 +/- 168 vs. 283 +/- 207 IU), hemoglobin (11.3 +/- 0.9 vs. 12.7 +/- 1.1 gr%), haptoglobin (479 +/- 136 vs. 451 +/- 121 mg/dL), fibrinogen (142 +/- 18 vs. 165 +/- 28 mg%), partial thromboplastin time (17.3 +/- 3.2 vs. 17.6 +/- 3.4 sec), prothrombin time (13.3 +/- 7.8 vs. 11.5 +/- 2.9 sec), and degree of platelet aggregation (55 +/- 17 vs. 62 +/- 8%). Thus, the data suggest that transluminal coronary sonication exerts no overt adverse effects in vivo.

Angioplasty, Balloon↗
PubMed1995

The impact of 'Shahal' (a new cardiac emergency service) on subscribers' requests for medical assistance: characteristics and distribution of calls.

The objectives of this study were to assess the impact of the new 'Shahal' (pre-hospital cardiac service) on subscribers' 'decision time'. A professional 24-h mobile emergency cardiac service has been set up, monitored by intensive care nurses via a central computerized operation unit. All subscribers carry a cardiobeeper for trans-telephonic transmission of a 3-lead electrocardiogram as well as an automatic intramuscular lidocaine injector for self-injection. During a 1-year period, data from 10,304 subscribers' charts were reviewed and analysed. Seventy-nine percent were cardiac patients and 15% were completely healthy. Median decision time for the general population was 44 min (range < 15 min to > 3 h); 59% of subscribers called within 1 h from onset of symptoms and 29% delayed calling for 3 h and more. The healthy subjects alerted the service significantly earlier (29 min). Three patterns of behaviour emerged from analysis of the daily distribution of calls.

Adolescent↗
PubMed1995

Right bundle branch block of unknown age in the setting of acute anterior myocardial infarction: an attempt to define who should be paced prophylactically.

It is widely accepted that patients presenting with acute anterior myocardial infarction and acute onset of right bundle branch block should be prophylactically paced in contrast with those who have a chronic bundle branch block. The admitting physician is faced with the dilemma of how to act if the age of this conduction disturbance is unknown. This problem has further intensified in recent years, with the introduction of thrombolytic treatment, where insertion of a central vascular line is associated with increased morbidity. The objectives of this study were to define clinical or electrocardiographic parameters that may help the admitting physician to decide whether patients presenting with an anterior wall myocardial infarction and a right bundle branch block of unknown age should be prophylactically paced. We examined prospectively the in-hospital clinical course of 39 consecutive patients presenting with an acute myocardial infarction in whom the age of a right bundle branch block upon admission was unknown (group C, n = 39) and compared with two similar groups of patients who presented with an acute right bundle branch block (group A, n = 38) and with a known chronic right bundle branch block (group B, n = 22). Thirty-three patients (33%) died, with cardiogenic shock being the leading cause of death in the entire population. Prophylactic pacing, which was carried out in 66% and 54% of patients in groups A and C, respectively, did not reduce mortality rates. No clinical or electrocardiographic variables on admission were predictive to support prophylactic pacing in group C. In 10 of 46 (22%) patients who were prophylactically paced with a transvenous electrode, the following complications attributed to the procedure were detected: (1) either rapid sustained ventricular tachycardia (during implantation) that was unresponsive to overdrive pacing, or ventricular fibrillation necessitating electrical defibrillation (4 patients); (2) recurrent episodes of rapid nonsustained ventricular tachycardia, which stopped only after the pacemaker was turned off (1 patient); (3) complete AV block (1 patient); (4) fever appearing on the third or fourth day after implantation (3 patients); and (4) a large hematoma in the groin in 1 patient who was treated with thrombolysis shortly before pacemaker electrode insertion. Thus, the complications of transvenous temporary pacing in the era of thrombolysis may outweight any theoretical advantage.

Acute Disease↗
PubMed1995

[The detection of Toxoplasma gondii in abortion tissues of sheep using the polymerase chain reaction].

A polymerase chain reaction was applied to detect Toxoplasma gondii DNA in placental and fetal tissue samples of 47 unselected ovine abortions of the lambing season 1990/91 (Baden-Württemberg, Rhineland, Hesse). For the amplification a 190 bp or 223 bp sequence of the B1-gene of T. gondii was selected as the target sequence. Both sequences were detected in five abortions. All positive results were immunohistochemically confirmed using the peroxidase antiperoxidase technique (PAP-staining). Thus, in Germany, too, T. gondii infection in sheep during pregnancy should be considered as a possible cause of abortions, particularly in case of abortions of unknown genesis.

Abortion, Veterinary↗
PubMed1994

[Do on-site coronary angiographic facilities influence management and prognosis of acute myocardial infarction?].

Whether the presence of on-site coronary angiographic facilities (CAF) influences the use of invasive coronary procedures and the outcome of acute myocardial infarction in coronary care units was studied. A prospective survey was conducted early in 1992 when 1014 consecutive patients with acute infarction were admitted. Of them 707 (70%) were admitted to coronary care units of hospitals with, and 307 (30%) without CAF. Thrombolytic therapy was given to 46% in both groups. Those admitted to hospitals with CAF underwent more coronary angiographies (26%) and percutaneous transluminal angiography and/or coronary artery bypass grafting (12%) than those without CAF (10 and 5%, respectively--p < 0.005). In-hospital and 1-year mortality were 11 and 18% respectively in those with CAF, vs 10 and 11%, respectively, in those without CAF. All patients treated with a thrombolytic agent had similar mortality, unrelated to the availability of CAF. The survey showed that the availability of on-site coronary angiography facilities led to greater use of invasive coronary procedures in cases of acute myocardial infarction, but there was no significant difference in mortality.

Angioplasty, Balloon, Coronary↗
PubMed1994

Functions of histone-like proteins in the initiation of DNA replication at oriC of Escherichia coli.

Using methidiumpropyl-EDTA (MPE) footprinting we found one specific binding site for FIS protein in the E coli replication origin, oriC. We mutagenized the binding sites for FIS and IHF in oriC and analyzed the effect of the mutations on protein binding and oriC function. The replication efficiency of oriC plasmids paralleled the ability of the mutated DNA fragments to bind IHF or FIS. We conclude that these histone-like proteins function in cis in the initiation of DNA replication at oriC.

Base Sequence↗
PubMed1994

A case of disseminated toxoplasmosis-value of PCR for the diagnosis.

Extracerebral toxoplasmosis has recently gained greater attention as a consequence of the AIDS epidemic. Serological techniques are unreliable, while isolation of the parasite is either time-consuming or insensitive. We here report a case of disseminated toxoplasmosis in a patient with AIDS. Diagnosis was suggested by serological tests and confirmed by PCR and Southern blot hybridisation or nested PCR. Detection of specific DNA was feasible in bronchoalveolar fluid, blood, serum and tissue samples. Direct detection of parasite-specific DNA by PCR and by nested PCR proved to be a promising, sensitive and rapid method for the diagnosis of disseminated toxoplasmosis, enabling us to promptly initiate specific treatment.

AIDS-Related Opportunistic Infections↗
PubMed1994

The use of intra-aortic balloon pump after surgical treatment of DeBakey type I dissecting aneurysm of the aorta.

The case is reported of a sixty-four-year-old patient with DeBakey type I aortic dissection in whom postoperative extensive intra-aortic balloon pumping was applied. Surgical repair involved replacing the ascending aorta with a Medtronic Hall valved conduit. After surgery severe low-output syndrome occurred. Despite the use of high-dose inotropic drugs the patient could not be hemodynamically stabilized. An intra-aortic balloon pump was finally applied as a therapeutical last resort. Within three days, under counterpulsation, the patient reached a stable hemodynamic condition. After twenty-one days in the intensive care unit, he could be transferred to a normal ward. The patient was discharged on the fifty-fourth postoperative day. During counterpulsation there were no balloon- or catheter-induced complications. Follow-up at five months showed the patient in good general health: echocardiography did not identify any lesions of the thoracic aorta which could be linked to counter-pulsation. It is concluded that the postoperative use of intra-aortic balloon pump in the event of DeBakey type I dissecting aneurysm of the aorta, and adversely affected patient hemodynamics, is a justifiable therapeutical alternative.

Aged↗
PubMed1994

Effect of magnesium on restenosis after percutaneous transluminal coronary angioplasty: a clinical and angiographic evaluation in a randomized patient population. A pilot study. The Ichilov Magnesium Study Group.

Restenosis is a major clinical problem following successful percutaneous transluminal coronary angioplasty. Since magnesium has vasodilator and antithrombotic effects, this study was designed to evaluate its potential to decrease the rate of restenosis. In an open-labelled, randomized controlled study, 148 patients underwent successful coronary angioplasty. Ninety-eight patients were treated with 46-52 mmol/18-20 h intravenous magnesium sulphate (groups M1 and M2), and 49 of them continued with oral supplements of magnesium hydroxide 600 mg.day-1 (group M2). The other 50 patients served as controls (group C). Coronary angiography was performed before, immediately after and at 6 months follow-up or earlier if clinically indicated. Clinical, laboratory, ergometric and radionuclide evaluations were also carried out. One hundred and thirty-nine patients (94%) with 163 dilated segments completed the study. Intravenous magnesium was well tolerated. The cross-sectional area at the site of angioplasty increased by 3.55 +/- 2.01 mm2 in groups M1 and M2 compared with an increase of 2.90 +/- 1.63 mm2 in the control group, (P = 0.03). A trend towards a lower rate of restenosis (> 50% reduction in luminal diameter) was noticed in the magnesium groups (28/110, 25%) compared with the control group (20/53, 38%) P = 0.10. Oral administration of magnesium was well tolerated, did not have an additive effect on restenosis, but an improved clinical course was noted. It is concluded that intravenous administration of magnesium in patients undergoing coronary angioplasty is feasible and safe and that the beneficial trend of magnesium to prevent acute recoil and late (within 6 months) restenosis is encouraging and should promote further investigation in a larger patient population.

Administration, Oral↗
PubMed1994

Value of PCR for evaluating occurrence of parasitemia in immunocompromised patients with cerebral and extracerebral toxoplasmosis.

PCR was used to evaluate the occurrence of Toxoplasma gondii parasitemia by detection of the B1 gene in blood samples in two groups of immunosuppressed patients (148 subjects) suspected of having cerebral or extracerebral infection, respectively. Group I consisted of 52 patients with AIDS with suspected cerebral toxoplasmosis. The diagnosis was clinically proven in 15 cases. Parasitemia was detected by PCR in only two of these patients (13.3%), both showing evidence of disseminated infection. Group II consisted of 96 immunocompromised patients, either with AIDS or receiving iatrogenic immunosuppressive therapy. Of these patients, 65 (34 with AIDS and 31 others) showed abnormalities only in chest radiography and were first screened for the presence of Toxoplasma DNA in bronchoalveolar lavage fluid. Blood was then analyzed when the parasite was detected in the bronchoalveolar lavage fluid. The remaining 31 subjects (22 with AIDS and 9 others) were suspected of having extracerebral, pulmonary, or disseminated toxoplasmosis, and blood was studied directly in these cases. Among the nine patients with clinically diagnosed extracerebral infection in group II, the parasite was detected by PCR in the blood of five patients (55.5%), all having pulmonary toxoplasmosis. If all patients with clinical manifestations of extracerebral toxoplasmosis (from both groups) who had not received antitoxoplasma therapy when the samples were collected are considered, PCR detected parasitemia in seven of the nine cases (77.8%). The present study indicates that examination of blood by PCR may be valuable in cases of extracerebral toxoplasmosis because of the disseminated nature of the disease. Since most cases of cerebral toxoplasmosis result from the local reactivation of latent brain cysts, detection of parasitemia by PCR is useful only in cases associated with severe cerebral infection or dissemination of this disease.

Acquired Immunodeficiency Syndrome↗
PubMed1994

Ocular rectus muscle insertions revisited: an unusual anatomic approach.

Twenty-five normal adult eyes, taken from fresh human cadavers, were specially prepared in view of the measurements of the arc length of different segments of the globe. The distances measured between the anterior limbus and the scleral insertions of the rectus muscles were similar to those in previous studies with respect to the 'spirale de Tillaux' and a high interindividual variability, i.e. medial rectus 6.2 +/- 0.6 mm, inferior rectus 7.0 +/- 0.6 mm, lateral rectus 7.7 +/- 0.7 mm, superior rectus 8.5 +/- 0.7 mm. The distance between each pair of opposite rectus muscle insertions shows a high interindividual variability (horizontal axis 25.45 +/- 1.38 mm, vertical axis 25.55 +/- 1.45 mm), but the ratio between both distances was always equal to 1 (0.997 +/- 0.031) with a statistically significant correlation (2-tailed p = 0.96). This new approach to rectus muscle insertions may be important for a better understanding of some possible anatomically related factors in strabismus.

Adult↗
PubMed1994

Percutaneous transluminal coronary angioplasty in elderly patients.

Fifty-six patients aged 75 years and older underwent percutaneous transluminal coronary angioplasty (PTCA) at our institution from 1984 to 1991. The average age was 76.7 +/- 1.5 years, and 84% of the patients were males. Single-vessel disease occurred in 21 patients, double-vessel disease in 16, and three-vessel disease in 19 patients. The mean left ventricular ejection fraction was 57 +/- 5%, and 8 patients had an ejection fraction of < 40%. The anginal functional class was I in 1 patient, II in 3, III in 6, and IV in 46 patients. Single-vessel PTCA was attempted in 43 patients, two-vessel PTCA in 8, and three-vessel PTCA in 5 patients. Revascularization was complete in 35% of the patients, incomplete in 57, and no revascularization was obtained in 8% of the patients. Ninety-one percent of the patients had a successful procedure. In 5 patients there was severe dissection, 1 patient died, 1 patient had an acute myocardial infarction, and 1 patient had emergency bypass surgery. Long-term follow-up (6-96 months, mean 21 +/- 4) in the 51 successfully treated patients revealed late cardiac death in 1 patient, repeated PTCA for restenosis in 9, and coronary bypass surgery in 2 patients. Twenty-two patients were asymptomatic, 12 had improved symptoms, and 5 remained symptomatic. PTCA appears to be a safe and effective treatment in elderly patients with one- and two-vessel disease, with excellent long-term results. Age is not a contraindication to PTCA. The results in elderly patients with three-vessel disease are less encouraging.

Aged↗
PubMed1994

Comparison of the determination of magnesium by methylthymol blue spectrophotometry and atomic absorption spectrophotometry.

Plasma samples (n = 155) of 30 patients on an intensive ward were analysed for magnesium simultaneously by atomic absorption spectrophotometry (AAS) and methylthymol blue spectrophotometry. Methylthymol blue spectrophotometry was performed at the bedside, using two different multianalysers, Easy ST 1 and Easy ST 2, Merck, D-Darmstadt. Precision was 12.2% (Easy ST 1) and 17.1% (Easy ST 2), and the average value was 0.89 mmol/l, which was above the expected range (0.72-0.88 mmol/l). Accuracy was 16.25% (Easy ST 1) and 8.75% (Easy ST 2). Analyser 2 was more accurate (8.75% versus 6.25%) but less precise (17.1% versus 12.2%) than analyser 1. Precision of AAS was between the expected values of 0.69 and 0.84 mmol/l. Easy ST and AAS gave significantly different values (p < 0.0001) for 155 measurements. Comparison of AAS and methylthymol blue spectrophotometery showed that methylthymol blue spectrophotometry produced higher values than AAS (mean difference 0.186 mmol/l). Furthermore, analyses of 40 samples of a standardized plasma concentration with methylthymol blue spectrophotometry showed a very low precision (15.3%). Easy ST cannot be assigned for urinary measurements of magnesium. Experimentally measured samples gave unaccountable results.

Bromthymol Blue↗
PubMed1994

Delirium associated with the combination of a neuroleptic, an SSRI, and benztropine.

BACKGROUND: On the basis of recent findings, the increased use of serotonin selective reuptake inhibitors (SSRIs) in combination with antipsychotics and concomitant benztropine is likely. METHOD: Five patients who developed delirium while receiving a neuroleptic, an SSRI, and benztropine are described. RESULTS: The timing of the delirium in relation to drug administration suggests the delirium was the result of an interaction of the SSRI and benztropine. CONCLUSION: Possible mechanisms are explored. Clinicians should be aware that patients receiving this combination may be at increased risk for delirium.

Aged↗