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Biomedical subjects

R Frank

Publications and source records attributed to R Frank.

At least 343 records · Page 19Linked to original sources
PubMed1989

Non-invasive study of dual chamber pacing by pulsed Doppler. Prediction of the haemodynamic response by echocardiographic measurements.

The increase in stroke volume with DDD compared with VVI pacing was measured at rest using pulsed Doppler echocardiography in 23 patients at a pacing rate of 70 beats min-1. Stroke volume was assessed by measuring the velocity integral of the flow at the aortic annulus using the apical five-chamber window. Pulsed Doppler echocardiography allowed determination of the least and most favourable AV delay haemodynamically. TVI was also measured at each nominal value of AV delay. The percentage increase in stroke volume was determined in every patient changing from VVI to optimum DDD pacing and was used as a measurement of the 'sensitivity' to optimum DDD pacing; the mean increase was 27 +/- 19%. The increase in stroke volume accompanying the change from DDD pacing with the least favourable to the optimum AV delay was also measured, and used as a measurement of 'sensitivity' to changes in AV delay; the mean increase was 23.7 +/- 16.3%. Clinical and standard echocardiographic parameters were studied in order to determine which variable might best identify the patients more likely to benefit from DDD pacing, and to identify those more sensitive to the AV delay setting. With respect to sensitivity to DDD pacing, three echocardiographic variables were selected by linear discriminant analysis from 11 clinical and echocardiographic variables. These were, in order of importance, left ventricular systolic diameter (LVSD), left ventricular wall thickness (LVWT) and left atrial size (LAS) which allowed the prediction of a good or a bad response to optimal DDD pacing with an accuracy of 91.3%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Mania in a girl with Cushing's disease.

A 13-year-old girl with Cushing's disease suffered a manic episode. An adenoma of the pituitary gland was found to be the cause. After the adenoma had been removed, the girl's condition returned to normal. The affective disorder was classified as an organic mood disorder (DSM-III-R).

Adenoma↗
PubMed1989

Cloning, sequencing and expression of a sialidase gene from Clostridium sordellii G12.

A 4.3 kb XbaI restriction fragment of DNA from Clostridium sordellii G12 hybridized with a synthetic oligonucleotide representing the N-terminus of the sialidase protein secreted by C. sordellii. This cloned fragment was shown to encode only part of the sialidase protein. The sialidase gene of C. sordellii was completed by a 0.7 kb RsaI restriction fragment overlapping one end of the XbaI fragment. After combining the two fragments and transformation of Escherichia coli, a clone that expressed sialidase was obtained. The nucleotide sequence of the sialidase gene of C. sordellii G12 was determined. The sequence of the 18 N-terminal amino acids of the purified extracellular enzyme perfectly matched the predicted amino acid sequence near the beginning of the structural gene. The amino acid sequence derived from the complete gene corresponds to a protein with a molecular mass of 44,735 Da. Upstream from the putative ATG initiation codon, ribosomal-binding site and promoter-like consensus sequences were found. The encoded protein has a leader sequence of 27 amino acids. The enzyme expressed in E. coli has similar properties to the enzyme isolated from C. sordellii, except for small differences in size and isoelectric point. Significant homology (70%) was found with a sialidase gene from C. perfringens.

Amino Acid Sequence↗
PubMed1989

Periodontal treatment needs in populations of high- and low-fluoride areas of Morocco.

The purpose of this study was to determine the periodontal status and treatment needs, using the CPITN index, in a population aged 7 to 60 years residing in the fluorosis area of Khouribga and the non-fluorosis area of Beni-Mellal, Morocco. A total of 2378 subjects was studied. In the youngest age groups, more subjects and sextants from Khouribga than from Beni-Mellal were free of periodontal diseases. Conversely, in Beni-Mellal, subjects in the youngest age groups presented a higher mean number of sextants with calculus than those from Khouribga. In combining the 2 areas, 1.3% of the 2319 dentate subjects examined needed no treatment and 98.7% needed at least oral hygiene instructions (TN1). The present study, based on the CPITN index, demonstrated in both areas a high prevalence of gingivitis, and a relatively low prevalence of deep pocketing, occurring on the average in less than half a sextant in the total populations.

Adolescent↗
PubMed1989

Familial thin basement membrane nephropathy in children with asymptomatic microhematuria.

A review of 130 children with persistent microhematuria showed that the most common abnormality was a form of hereditary nephritis for wich we propose the term 'familial thin basement membrane nephropathy' (FTBMN). This lesion is not as severe as that of Alport's syndrome but carries a guarded prognosis. Family histories, urinalyses and audiograms systematically done on parents and other relatives show that FTBMN may be present in as many as 39% of children with persistent microhematuria and that careful family studies identify children likely to have this lesion.

Adolescent↗
PubMed1989

Regional deposition of inhaled fog droplets: preliminary observations.

The regional deposition of a monodisperse 10-micron mass median aerodynamic diameter fog was studied in four healthy adult male nonsmokers. The fog was radiolabeled with technetium-99m sulfur colloid to enable detection by an Anger camera of deposited activity in the following regions of the respiratory tract: oropharynx, larynx, trachea, and intrapulmonary airways. Intrapulmonary deposition was further analyzed by computer with inner, intermediate, and outer zones, and within apical, intermediate and basal zones of the right lung. The radiolabeled aerosol was inhaled by mouth through a face-mask with the nasal airway occluded. Respiratory frequency, tidal volume, and jaw position were controlled and were commensurate with the oral component of oronasal breathing during moderate exercise. Deposition in the larynx, trachea, and intrapulmonary airways was a function of the scrubbing efficiency of the oropharynx, which differed substantially among subjects, and ranged from 72 to 99%. The density of the aerosol deposit in the larynx probably exceeded that of any of the subdivisions of the tracheobronchial tree and lung. Within the lung, deposition favored the inner zone (assumed to contain the larger airways) over the outer zone (assumed to be dominated by smaller airways and alveoli). Intrapulmonary aerosol distribution in an elderly subject with borderline evidence of airway obstruction differed from that observed in younger subjects. The possible consequences of altered lung elastic recoil, as may occur with aging, for regional dosimetry is discussed.

Acid Rain↗
PubMed1989

Clinical experience with fulguration and antiarrhythmic therapy for the treatment of ventricular tachycardia. Long-term follow-up of 43 patients.

Forty-three patients (mean age, 45 +/- 18 years) with drug-refractory VT of varied etiologies, including 15 cases occurring after chronic myocardial infarction, underwent fulguration procedures. With a mean follow-up of 29 +/- 12 months (range, 9 to 55 months), after one to four sessions, VT had been controlled without a need for antiarrhythmic drugs in 22 (56 percent) of the 39 patients surviving the perioperative period and was controlled in 17 patients (44 percent) with the help of drugs. No malignant arrhythmias were observed following fulguration. There were five early deaths, four deaths related to the procedure, and eight late deaths, but no death was thought to be related to the endocardial shock itself. Thus, fulguration appears to be a valuable adjunct to the treatment of drug-resistant VT.

Adolescent↗
PubMed1989

The incestoid family.

Following a short overall view on family therapeutic models of close family systems and on incest family models, the concept "incestoid family" is conceived. In this way, families should be exemplified in which it is true that no manifest incest occurs, but by going from one generation to another, relationships between parents and children, resembling a relationship between partners and the constellation of subliminal enticement and seduction situations promote pseudosexual behaviour patterns; the most conspicuous symptom of such a family is hyper- as well as hyposexualised behaviour in children and young people. Definitive and conceptual demarcations to oedipal and incestuous structures were undertaken. Four case descriptions should illustrate the clinic of incestoid families.

Adolescent↗
PubMed1989

[Causes of sudden death in athletes].

Sudden death is rare in athletes, and it is only in recent years that significant series were collected, making it possible to draw the cardiological profile of athletes who died suddenly at the peak of exertion or while recovering. A study of the literature, both medical and paramedical, has yielded 53 cases in which the most frequent causes of sudden death were hypertrophic cardiomyopathy (26 p. 100), (arrhythmogenic right ventricular disease (19 p. 100), congenital abnormalities of coronary arteries (11 p. 100) and coronary atheromatous lesions (9 p. 100), to which must be added various other causes. This study clearly demonstrates the hitherto unrecognized importance of arrhythmogenic right ventricular dysplasia-a condition which, as recent data suggest, is not solely due to a myocardial development disorder but also to an infective disease, an acute of chronic myocarditis. In subjects with this condition, new exploratory methods might detect the presence of an arrhythmogenic substrate during medical screening of athletes, but in any case these causes of sudden death suggest that a fast rhythm disorder was involved in several of these deaths. This disorder could be treated if the attendants were trained to carry out cardiorespiratory resuscitation procedures or if they had access to a defibrillator which should be available on every sports field.

Adult↗
PubMed1989

[Efficacy of the combination of low doses of beta-blockers and amiodarone in the treatment of refractory ventricular tachycardia].

Thirty one patients aged 56 +/- 16 years with chronic ventricular tachycardias (VT) refractory to 4.4 +/- 1.8 antiarrhythmic drugs, used alone or in combination, were managed by low doses of beta-blocker agents combined with oral amiodarone, either after loading (1.2 g for 7 days, n : 7) or reloading (1.2 g for 4 days, n : 24) of amiodarone. All patients proved refractory to amiodarone alone. Nine VT were also refractory to endocardial catheter fulguration in 8 patients. Twenty one patients had coronary artery disease, 4 had arrhythmogenic right ventricular dysplasia, 4 had dilated cardiomyopathy, 1 had valvular disease, and 1 had no structural heart disease. Twelve patients had an ejection fraction less than 30 p. 100. Ten patients were in NYHA functional class 3. VT was permanent in 3 patients, daily in 5, weekly in 7, paroxysmal in 16. In 14 patients, VT occurred both at day and night. Oral administration of a daily low dose of a beta-blocker agent (acebutolol 100 mg, betaxolol 5-10 mg, metoprolol 50-100 mg, nadolol 20-40 mg, pindolol 2.5 mg, propranolol 30 mg, sotalol 80-160 mg, tertatolol 2.5 mg) combined with 400 mg per day of amiodarone suppressed VT episodes in all patients. None presented heart failure or collapse. The mean reduction of the heart rate was about 17 p. 100. One patient need a definite pacemaker to correct sinus bradycardia. At discharge, exercise ECG (n: 20) induced non sustained VT in 2 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

The latent factor structure of the WAIS-R: a factor analysis of individual item responses.

Factor analytic examination of a 166 x 166 intercorrelational matrix that represents individual item scores from the 11 subtests of the WAIS-R provided evidence of five interpretable factors (N = 409). Two of these were identified as the Verbal and Performance factors previously encountered in traditional WAIS-R subtest-based factor analyses. The other three factors were characterized readily as involving (1) Advanced Vocabulary skills; (2) Basic Responsivity and (3) Advanced Computational ability. All three of these "new" factors accounted for at least 10% of the total variance, and comments are made with regard to the possible significance of their discovery to such topics as subtest variation and profile psychodiagnostics, theories that pertain to the nature and structure of human intellectual functioning, and subtest-based personality measurement theories.

Adult↗
PubMed1988

Immunochemical detection of the alpha-subunit of the G-protein, GZ, in membranes and cytosols of mammalian cells.

An antiserum (AS 98) was raised against a synthetic peptide deduced from published cDNA sequences of the alpha-subunit of the putative G-protein, GZ (Fong et al. Proc. Natl. Acad. Sci. USA 85, 3066-3070, 1988; Matsuoka et al. Proc. Natl. Acad. Sci. USA 85, 5384-5388, 1988). In membrane and cytosol preparations of many but not all tested mammalian tissues, AS 98 predominantly recognized two proteins of 40 and 43 kDa Mr. Whereas high levels of a 40 kDa GZ alpha-subunit were found in rat liver membranes and in brain cytosol, AS 98 failed to detect the alpha-subunit of GZ in brain membranes.

Amino Acid Sequence↗
PubMed1988

Interaction of DNA hairpin loops and a complementary strand by a triplet of base pairs.

Hypothesis of non-enzymatic recognition of primordial tRNA and mRNA precursors is experimentally approached. DNA hairpins containing a different number of deoxyguanosine residues in the loop are analyzed for their binding ability to a chemically fixed single-strand of oligo(dC). In presence of small Mg2+ concentration a hairpin with five dG residues in the loop is adsorbed to affinity matrix. Comparison of elution temperatures of hairpin oligonucleotides with those of single-stranded oligoguanylic acids with length of the loop indicates, that smallest loop able to bind forms a triplet of base pairs.

Adsorption↗
PubMed1988

Catalytic-site mapping of pyruvate formate lyase. Hypophosphite reaction on the acetyl-enzyme intermediate affords carbon-phosphorus bond synthesis (1-hydroxyethylphosphonate).

Pyruvate formate-lyase of Escherichia coli cells, a homodimeric protein of 2 x 85 kDa, is distinguished by the property of containing a stable organic free radical (g = 2.0037) in its resting state. The enzyme (E-SH) achieves pyruvate conversion to acetyl-CoA via two distinct half-reactions (E-SH + pyruvate in equilibrium E-S-acetyl + formate; E-S-acetyl + CoA in equilibrium E-SH + acetyl-CoA), the first of which has been proposed to involve reversible homolytic carbon-carbon bond cleavage [J. Knappe et al. (1984) Proc. Natl Acad. Sci. USA 81, 1332-1335]. Present studies identified Cys-419 as the covalent-catalytic cysteinyl residue via CNBr fragmentation of E-S-[14C]acetyl and radio-sequencing of the isolated peptide CB-Ac (amino acid residues 406-423). Reaction of the formate analogue hypophosphite with E-S-acetyl was investigated and found to produce 1-hydroxyethylphosphonate with a thioester linkage to the adjacent Cys-418. The structure was determined from the chymotryptic peptide CH-P (amino acid residues 415-425), using 31P-NMR spectroscopy (delta = 44 ppm) and by chemical characterisation through degradation into 1-hydroxyethylphosphonate with phosphodiesterase or bromine. This novel P-C-bond synthesis involves the enzyme-based free radical and is proposed to resemble the physiological C-C-bond synthesis (pyruvate production) from formate and E-S-acetyl. These findings are interpreted as proof of a radical mechanism for the action of pyruvate formate-lyase. The central Cys-418/Cys-419 pair of the active site shows a distinctive thiolate property even in the inactive (nonradical) form of the enzyme, as determined using an iodoacetate probe.

Acetyl Coenzyme A↗
PubMed1988

The primary structure of the 70 kDa subunit of bovine soluble guanylate cyclase.

The primary structure of the 70 kDa subunit of soluble bovine guanylate cyclase, which catalyzes the formation of cyclic GMP from GTP, has been determined. The alignment of six different clones out of two bovine libraries yielded a total of 3.1 kb with a coding region of 1857 bases. The open reading frame encodes a protein of 619 amino acids and a molecular mass of 70.5 kDa. Antibodies raised against a synthetic peptide, which corresponded to the C-terminus of the deduced sequence precipitated guanylate cyclase activity from guanylate cyclase-enriched preparations.

Amino Acid Sequence↗
PubMed1988

Primary structures of Escherichia coli pyruvate formate-lyase and pyruvate-formate-lyase-activating enzyme deduced from the DNA nucleotide sequences.

The structural gene of pyruvate formate-lyase (pfl) and that of pyruvate-formate-lyase-activating enzyme were shown to be adjacent on the chromosomal map of Escherichia coli. DNA sequencing was performed along a stretch of 3592 nucleotides to obtain the amino acid sequences of both proteins. The derived primary structures (759 and 245 residues) were confirmed by partial structure analyses on the purified proteins. The open reading frames are separated by a 194-nucleotide stretch, and their flanking regions include signal elements that are compatible with separate control of protein synthesis from the two genes.

Acetyltransferases↗