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Biomedical subjects

E Ferrari

Publications and source records attributed to E Ferrari.

At least 289 records · Page 16Linked to original sources
PubMed1988

A sensitive cadmium-affinity assay for the determination of thionein in urine.

A sensitive cadmium-affinity assay was developed for measurement of urinary thionein (Th) level. Acidification with HCl (2.5 M) was used to remove metal ions from purified urinary metallothionein (MTh), adsorbed on activated polystyrene tubes. It was found that the amount of 109Cd bound to standard Th (rabbit Th) was proportional to that of Th in the concentration range of 20-6000 ng/ml. The method exhibited a sensitivity below 20 ng/ml and a precision of about 5%. The results of the Cd-affinity assay were unaffected by dilution of, or addition of standard Th to urine samples. Under the latter circumstances, the Cd-affinity assay was performed with a mean analytical recovery of 100.3 +/- 4%. Addition of Cd, Zn, Hg and Cu (50 micrograms each) or glutathione and cysteine (0.1 mmol) to urine specimens (1 ml) did not interfere with the determination of Th. The mean values of urinary Th in healthy subjects were 200 +/- 53 micrograms/g creatinine (n = 9) and 256 +/- 97 micrograms/g creatinine (n = 8) for men and women respectively. The mean daily excretions of Th by non-fasting female and male healthy adult rats were 9.95 +/- 2.7 micrograms (n = 10) and 18.2 +/- 3.9 micrograms, respectively. The Cd-affinity assay succeeded in indicating Cd exposure and/or development of Cd toxicity in rats.

Animals↗
PubMed1988

The combination of a low-Na/high-K salt with metoprolol in the treatment of mild-moderate hypertension. A multicenter study.

To extend our previous findings that a low-Na/high-K salt (S) reduces BP in hospitalized patients, a multicenter study was performed. After a placebo period during which patients were informed by written instruction how to avoid only foods with a high Na content, 143 out-patients (84 males and 59 females, mean age 50.7 years, range 28-69) with DBP greater than or equal to 95 mm Hg randomly received for 4 weeks either metoprolol (M) 200 mg SR qd (67 patients), or S, 2 g bid to add to foods (76 patients). At the end of this period patients with DBP still greater than 90 mm Hg combined the two treatments for a further 4 weeks. Mean blood pressure (mm Hg), HR (bpm), 24-hrs urinary Na and K excretion were measured fortnightly. In comparison to pretreatment values MBP was significantly (P less than 0.01) reduced by both treatments, although to a greater extent in the M group already at the second week, without any further decrement thereafter. In the S group MBP decreased by 4.4 mm Hg and 27/76 patients were responders (DBP less than or equal to 90 mm Hg), while in the M group it was reduced by 9.0 mm Hg and 28/67 patients were responders. In the S group urinary Na excretion was significantly (P less than 0.01) lower than in the M group, and this difference was present until the end of period 1.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Association between hormonal and haemorheological changes during the menstrual cycle in healthy women.

Blood rheology was studied in 15 healthy women throughout a normal menstrual cycle. Significant increases in fibrinogen, blood and plasma viscosity, and a reduction of erythrocyte filtrability were demonstrated during the follicular and ovulatory phase in comparison with mid- and late luteal phase of the menstrual cycle. Positive correlations were found between oestradiol levels and the haemorheological variables. Our data suggest that ovarian hormonal activity influences haemorheology and blood flow in healthy women.

Adult↗
PubMed1988

Transcription of Bacillus subtilis subtilisin and expression of subtilisin in sporulation mutants.

The start point for transcription of the subtilisin (aprE) gene was determined by primer extension analysis and was found to be at a point significantly different from that identified in a previously published report (S. L. Wong, C. W. Price, D. S. Goldfarb, and R. H. Doi, Proc. Natl. Acad. Sci. USA 81:1184-1188, 1984). An aprE-lacZ fusion was used to analyze expression of the promoter. Deletion analyses of the promoter were performed to determine the extent of the upstream region necessary for activity. This was found to be between -52 and -41 with respect to the transcription start site. Expression of the aprE-lacZ fusion was unimpaired in a mutant deleted for the sigma B subunit of RNA polymerase. Mutations in the gene for the sigma H subunit of RNA polymerase decreased expression of the aprE-lacZ fusion to approximately 25% of that of the wild type. These results leave the identity of the sigma factor responsible for transcription of this gene in question. Mutations in the spo0A gene drastically decreased the activity of the aprE promoter and its upstream deletion derivatives, while the abrB gene, a phenotypic suppressor of spo0 mutations, restored activity of the aprE promoter in all of the deletion derivatives. Thus, inhibition of transcription by the spo0A mutation and its restoration by an abrB mutation could not be separated from the promoter of the aprE gene.

Bacillus subtilis↗
PubMed1988

Location of the targets of the hpr-97, sacU32(Hy), and sacQ36(Hy) mutations in upstream regions of the subtilisin promoter.

A number of mutations have been described with pleiotropic effects on the expression of genes for degradative enzymes in Bacillus subtilis. The sacU32(Hy) and sacQ36(Hy) mutations increase the expression of a wide variety of enzymes that degrade biological polymers. The phenotypes caused by mutations at the hpr locus are more restricted; they are known to increase expression of the alkaline and neutral proteases. The alkaline protease (aprE) promoter was analyzed to determine the target site for stimulation by these loci. Deletion of upstream regions of the aprE promoter could abolish or greatly reduce stimulation by mutations at these loci. A region upstream of -200 was necessary for full stimulation by an hpr-97 mutation, whereas a region between -141 and -164 was necessary for full stimulation by the sacU32(Hy) and sacQ36(Hy) mutations. Northern analyses of mRNA preparations showed that the levels of aprE mRNA were increased in strains carrying the sacU32(Hy) or hpr-97 mutation. Moreover, primer extension analysis of these mRNA preparations revealed that the transcription start point was identical to that in a wild-type strain. We hypothesize that upstream activation of the subtilisin promoter mediated by these genes is a mechanism for global responses to a variety of nutritional conditions.

Bacillus subtilis↗
PubMed1988

Localization of Bacillus subtilis sacU(Hy) mutations to two linked genes with similarities to the conserved procaryotic family of two-component signalling systems.

Mutations in the sacU region have a pleiotropic phenotype. Certain mutations designated sacU(Hy), for example, express degradative enzymes at high levels, are able to sporulate in the presence of glucose, have severely reduced transformation efficiencies, and are nonmotile. We isolated and sequenced the sacU gene region of Bacillus subtilis. Two open reading frames were found in the sacU region, and sacU(Hy) mutations were localized to both of these open reading frames. The two open reading frames have similarities to two widespread families of proteins that mediate responses to environmental stimuli.

Amino Acid Sequence↗
PubMed1988

Prolactin secretion in polycystic ovary syndrome: circadian rhythmicity and dynamic aspects.

The circadian rhythms of plasma prolactin (PRL) and cortisol and of oral temperature were simultaneously studied in 24 women with polycystic ovary syndrome (PCOS). The PRL response to thyrotropin-releasing hormone (TRH) and domperidone was also evaluated in some of these patients. The physiological circadian chrono-organization of prolactin and cortisol secretion and of oral temperature was maintained in PCOS. The PRL responsiveness to the specific stimulations fell within normal limits. These results do not support the hypothesis of an impaired central dopaminergic regulation of prolactin secretion in PCOS.

Adolescent↗
PubMed1988

[Cephalometric evaluation of lower incisor position].

The Authors examined some cephalometric values usually utilized to evaluate lower incisors inclination or anteroposterior position. Mean values and standard deviations of these parameters in a 194 subjects sample was calculated. Validity of these valued in different typology and skeletric classes was finally verified.

Adolescent↗
PubMed1987

Mammalian DNA polymerase alpha: a replication-competent holoenzyme form from calf thymus.

Calf thymus DNA polymerase alpha, like the replication-specific DNA polymerase III holoenzyme of Escherichia coli, can be isolated as a distinct complex. A specific multiprotein form of the polymerase alpha, a form designated replication-competent (RC) holoenzyme, consists of a complex of a polymerase-primase core and at least six other polypeptides. The RC holoenzyme can efficiently replicate several naturally occurring templates, including the genomic DNA of the porcine circovirus (PCV). The DNA of this virion consists of a single-stranded circle with a defined replication origin, and its replication requires the cellular DNA replication machinery. It might therefore provide an invaluable opportunity to investigate chromosomal replication mechanisms, analogous to the way that studies on E. coli bacteriophage DNA replication elucidated host DNA replication mechanisms. Calf RC holoenzyme alpha selectively initiates PCV DNA replication in vitro at a site that possibly represents a consensus sequence of cellular DNA replication origins. The cell-free PCV replication system will be exploited for the in vitro dissection and reconstitution of the RC holoenzyme and the functional analysis of its component polypeptides.

Animals↗
PubMed1987

Molecular cloning of Bacillus subtilis genes involved in DNA metabolism.

Different clones carrying a chromosomal DNA fragment able to transform Bacillus subtilis mutants dnaA13, dnaB19, dnaG5, recG40 and polA42 to a wild-type phenotype were isolated from a library constructed in plasmid pJH101. A lambda recombinant clone carrying a chromosomal fragment able to transform dnaC mutants was obtained from a lambda Charon 4A library. A restriction map of the cloned DNA fragments was constructed. The 11.3 kb cloned DNA fragment of plasmid pMP60-13 containing the wild-type sequence of dnaG5 was shown to transform a recF33 mutant as well.

Bacillus subtilis↗
PubMed1987

Characterization of the levanase gene of Bacillus subtilis which shows homology to yeast invertase.

The structural gene for the enzyme levanase of Bacillus subtilis (SacC) was cloned in Escherichia coli. The cloned gene was mapped by PBS1 transduction near the sacL locus on the B. subtilis chromosome, between leuA and aroD. Expression of the enzyme was demonstrated both in B. subtilis and in E. coli. The presence of sacC allowed E. coli to grow on sucrose as the sole carbon source. The complete nucleotide sequence of sacC was determined. It includes an open reading frame of 2,031 bp, coding for a protein with calculated molecular weight of 75,866 Da, including a putative signal peptide similar to precursors of secreted proteins found in Bacilli. The apparent molecular weight of purified levanase is 73 kDa. The sacC gene product was characterized in an in vitro system and in a minicell-producing strain of E. coli, confirming the existence of a precursor form of levanase of about 75 kDa. Comparison of the predicted aminoacid sequence of levanase with those of the two other known beta-D-fructofuranosidases of B. subtilis indicated a homology with sucrase, but not with levansucrase. A stronger homology was detected with the N-terminal region of yeast invertase, suggesting the existence of a common ancestor.

Amino Acid Sequence↗
PubMed1987

Characterization and mapping of the Bacillus subtilis prtR gene.

A gene from Bacillus natto encoding a 60-amino-acid peptide has been previously described that, when cloned on a high-copy plasmid in B. subtilis, enhances production of alkaline protease, neutral protease, and levansucrase. An identical gene was isolated from B. subtilis and caused a similar phenotype when placed on a high-copy plasmid. Genetic mapping localized this gene near metB, distant from other pleiotropic genes causing similar effects. Deletion of this gene from the B. subtilis chromosome had no obvious phenotypic effect.

Amino Acid Sequence↗
PubMed1987

Nucleotide sequence of the outB locus of Bacillus subtilis and regulation of its expression.

The outB gene is one of the genes involved in the process of spore outgrowth in Bacillus subtilis. The gene has been cloned in bacteriophage lambda and subcloned in plasmids. We have determined the sequence of 2,553 base pairs around the outB locus. The locus was found to code for a protein of about 30,000 daltons. Analysis of the in vivo transcripts from this region by RNase protection experiments revealed the presence of two start sites for transcription. Two potential promoters for these transcripts can be tentatively assigned from the sequence data. The amount of one transcript is highest during outgrowth and vegetative growth and absent during the stationary phase. The second transcript is present at a low level throughout the cell cycle.

Bacillus subtilis↗
PubMed1987

Circulating opioids and plasma renin activity in insulin-dependent diabetics with renal haemodynamic alterations.

Circulating opioids were studied in insulin-dependent diabetics with renal haemodynamic alterations. Higher circulating beta-endorphin (beta-EP) and lower beta-lipotropin (beta-LPH) levels were found in patients with glomerular hyperfiltration than in diabetics with normal glomerular filtration rate (GFR) and controls. Moreover, significantly positive correlations between beta-EP and GFR, and between beta-EP and renal plasma flow were demonstrated in these patients. On the contrary, reduced beta-EP levels were observed in diabetics with impaired GFR and overt nephropathy. Plasma renin activity was increased in diabetics with glomerular hyperfiltration and reduced in diabetics with overt nephropathy. Circulating opioids might, therefore, play a role in renal haemodynamic alterations, both in patients with early and advanced glomerular changes.

Adult↗