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G Neri

Publications and source records attributed to G Neri.

At least 181 records · Page 10Linked to original sources
PubMed1995

Efficient one-step direct labelling of recombinant antibodies with technetium-99m.

High-affinity bacterially expressed antibody fragments can nowadays be cloned from established hybridomas or, more conveniently, isolated directly from antibody libraries displayed on filamentous phage. Such antibodies can be tagged with C-terminal peptide tags containing one cysteine residue, which represents a convenient functionalisation site for a number of applications, including technetium-99m labelling. Here we describe a simple one-step method for 99mTc labelling of cysteine-tagged recombinant antibodies with more than 50% radionuclide incorporation. The labelled antibodies displayed full retention of immuoreactivity and good stability.

Antibodies, Bacterial↗
PubMed1995

Effects of sex hormones on the steroidogenic activity of dispersed adrenocortical cells of the rat adrenal cortex.

The effect of 17 beta-estradiol and testosterone on glucocorticoid secretion were studied in vitro by using dispersed inner adrenocortical cells obtained from gonadectomized female and male rats. Independently of the sex of animals, estradiol enhanced basal, but not ACTH-stimulated corticosterone (B) secretion; conversely, testosterone inhibited ACTH-stimulated, but not basal B output. HPLC analysis of steroid secreted demonstrated that estradiol induced comparable rises (53-62%) in basal pregnenolone (PREG) and total post-PREG secretion (progesterone, 11-deoxycorticosterone and B). Testosterone inhibited by about 30% ACTH-stimulated PREG production and by about 54% total post-PREG secretion (B was decreased to 56% of the control value, and other steroid hormones were below the limit of sensitivity of our assay system). These findings indicate that sex hormones directly affect rat adrenocortical secretion, mainly by acting on the rate-limiting step of steroidogenesis (i.e. the conversion of cholesterol to PREG); moreover, they suggest that testosterone is also able depress the activity of the enzymes operating distally to cholesterol side-chain cleavage.

Adrenal Cortex↗
PubMed1995

First report of t(8;21)(q22;q22) in a case of de novo acute monoblastic leukemia.

Here we describe the case of a 30-year-old man with a diagnosis of de novo acute monoblastic leukemia (FAB M5a), whose karyotype analysis revealed the presence of the translocation (8;21)(q22;q22) as the sole chromosome anomaly. In spite of the rather good prognosis patients suffering from acute leukemia and carrying this translocation are supposed to have, our patient had a very poor outcome, including an early relapse resistant to any treatment and meningeal localization. Death occurred within 5 months from diagnosis. To our knowledge this is the first report of t(8;21)(q22;q22) in de novo acute monoblastic leukemia.

Adult↗
PubMed1995

Trisomy 4 as the sole karyotypic anomaly in acute biphenotypic leukemia with B lineage markers and in acute minimally differentiated myeloid leukemia (M0).

Trisomy 4 is a recently defined chromosomal aberration in acute leukemia. The first reports suggested that this cytogenetic anomaly belongs to the M4 leukemia subtype of the FAB classification, but recent reports have described this alteration in a wider spectrum of leukemia subtypes. Here we report two cases of trisomy 4 as the sole chromosome anomaly: one was observed in a patient with acute biphenotypic leukemia with B-lineage markers and the second in a patient diagnosed with acute minimally differentiated myeloid leukemia (M0) with myelodysplastic features. To our knowledge these are, respectively, the first and second reports of trisomy 4 as the sole chromosomal anomaly in these leukemia subtypes.

Acute Disease↗
PubMed1995

Morphology and function of the adrenal zona glomerulosa of transgenic rats TGR [mREN2] 27: effects of prolonged sodium restriction.

Heterozygous female transgenic rats for the murine Ren-2 gene (TGR) display a high blood pressure, together with a low kidney and high adrenal renin content. The effects of prolonged sodium restriction on the morphology and secretory activity of adrenal zona glomerulosa (ZG) of TGR and their age- and sex-matched Sprague-Dawley control rats (SDR) were investigated. Under basal conditions, TGR had a moderately hypertrophic ZG, that showed a significantly higher secretion of 18-hydroxylated (18OH) steroids: 18-hydroxy-11-deoxycorticosterone (18OH-DOC), 18-hydroxycorticosterone (18OH-B) and aldosterone (ALDO); ZG cells of TGR showed angiotensin II (AII)-binding site concentrations and ALDO secretory responses to AII similar to those of SDR ZG cells. Prolonged sodium restriction increased plasma ALDO level in both SDR and TGR, and significantly raised the volume of ZG. ZG hypertrophy was due to the increase in both the number and average volume of its parenchymal cells. The secretion of 18OH-steroids was markedly enhanced in both groups of rats; however, in TGR this rise was exclusively due to increases of 18OH-DOC and 18OH-B, while in SDR also ALDO production was enhanced. The yield of non-18OH-steroids was not affected. 11-Dehydrocorticosterone production was not changed in SDR, but doubled in TGR. ZG cells of sodium-restricted SDR and TGR displayed similar increases in their AII-binding site concentration and ALDO secretory response to AII. In conclusion, our present findings confirm that TGR possess a hypertrophic ZG and an elevated secretory capacity o 18OH-steroids, but show only slight differences in ZG and ZG-cell responses to prolonged sodium deprivation.

Animals↗
PubMed1995

Dicentric chromosome Y associated with Leydig cell agenesis and sex reversal.

The nature of a non-mosaic marker Y chromosome observed in a pseudohermaphrodite patient with Leydig cell agenesis was investigated by high-resolution chromosome analysis and molecular probes from the Y chromosome. Cytogenetically, the marker chromosome appeared to be an isodicentric, with breakage in Yq11.21. Double copies of all Yp-specific loci tested, including SRY, were present. The most distal Yq portion detected in patient DNA was DXS278-C, which maps to interval D in the chromosome Yq deletion map. Fragment DXS278-B, which maps to deletion interval E, was absent. The possible relationship between this cytogenetic abnormality and Leydig cell agenesis, a finding never reported in association with Y chromosome rearrangements, is discussed.

Adolescent↗
PubMed1995

Botulinum toxin-A for the treatment of hemifacial spasm.

Management of hemifacial spasm can actually be done medically, surgically and with Botulinum-A Toxin. The Botulinum-A Toxin treatment locally injected into the involved facial muscles offers a useful alternative to medical and surgical therapy. The objective of this study was to evaluate the efficacy of Botulinum-A Toxin for the treatment of hemifacial spasm in those subjects for whom the presently available medical therapy is inadequate. A total of 28 individuals were enrolled in the clinical study. Patients were evaluated using the Fahn's blepharospasm rating and disability scales. Efficacy was assessed by evaluating changes from the baseline in eyelid spasm intensity, brow spasm intensity, eyelid force and facial spasm intensity. All 28 subjects with hemifacial spasm showed clinical improvement in relation to this baseline, which was statistically significant. The mean decrease from baseline at their follow-up examination was statistically significant for all subjects and for all measurements: eyelid spasm changed from 2.3 to 0.3 (p = 0.0001); brow spasm from 1.9 to 0.1 (p = 0.0001); facial spasm from 2.3 to 0.1 (p = 0.0001) and eyelid force from 0.9 to -0.1 (p = 0.0020). We concluded that Botulinum-A Toxin provides a significant therapeutic benefit to patients with hemifacial spasm, without the risk of disabling side effects.

Adult↗
PubMed1995

[Auditory brain stem evoked potentials in the evaluation of chronic fatigue syndrome].

The Chronic Fatigue Syndrome (CFS) was formally defined to describe disabling fatigue of multifactorial ethology with depression and immunologic dysfunctions linked to some currently recognized infectious agents. In most cases neurophysiological tests reveal abnormalities. In this paper the Authors use low (11 pps) and high (51-71 pps) frequency ABR to evaluate the electrophysiological function of auditory brainstem responses. Eighteen patients with suspected CFS, between the ages of 17 and 63, were examined. Eleven subjects had clinically diagnosed "true" CFS (CDC criteria modified by Fukuda). The 11 pps frequency test did not reveal a high number of abnormalities in the patients in question. However, the high frequency stimulation test (with 51 and 71 pps) which was statistically significant (P = 0.009) revealed numerous aberrations in 7 patients; absence of the first wave in 1 case, in 5 numerous wave gap delays and in 1 patient absence of the first wave and numerous wave gap delays. The high frequency test did not show many abnormalities for the 4 remaining patients. For the 7 "non CFS" subjects, the clinical-audiological comparison showed no statistical significance (P = 0.920). The Authors hypothesize that the absence of the first wave in the CFS Subject may well indicate a cyto-neural junction disease in the organ of Corti. The combined analysis of clinical and audiological data showed that the described tests are more reliable when employed in dealing with patients with clinically assessed "true" CFS.

Adolescent↗
PubMed1995

[Widened forwarding total laryngectomy ("squared laryngectomy"). Hints of surgical techniques and personal experience].

Primitive T4 laryngeal neoplasms with anterior invasion and neoplasm recurring after partial and subtotal intervention often invade the soft prelaryngeal tissues and in these cases the neoplastic illness can be no longer be controlled be "organ surgery". The widened forwarding total laryngectomy, "squared" or "carrè" laryngectomy according to some Authors of French School, is a surgical procedure not "on an organ" but "in an area" or "region" which proposes to delete, in one step, the larynx, the bone hyoid, the fasciae and the prelaryngeal muscles, the thyroid gland and, if necessary, a more or less large quantity of anterior cervical skin. If the removal involves a vast cutaneous area, it is necessary to mend the loss of substance by wrapping around a miocutaneous flap of pectoralis mayor muscle. In the last five years, 4 male patients, between 48 and 73 years, were treated with widened forwarding total laryngectomy. They were all carriers of epidermoid laryngeal carcinomas with various degrees of differentation: primitive in one patients, recidivist after performance of partial (cordectomy) and subtotal (two Labayle) surgery in the other three patients. In the only case of T4 primitive laryngeal neoplasm it was necessary to carry out a functional neck dissection bilaterally. Loss of substance always required the use of a miocutaneous flap of pectoralis mayor muscle except in one patient in which the removal of the prelaryngeal tissues was limited and therefore it was possible to make a direct seam. We always completely removed the thyroid gland, the prelaryngeal muscular system and skin of the preceding stomy (in the Labayle) sparing, on the other hand, the hyoid bone. Only one patient, who died due to recurrence a year after surgery, underwent complemental percutaneous radiotherapy. At present, three patients are alive and NED: one after 5 years, the others are in excellent conditions although the follow-up is still brief. According to our experience, we can affirm that in selected cases, after an accurate general evaluation of the patient (exclusion of distant metastases, preparation from a metabolic and psychological point of view) a widened forwarding total laryngectomy is a valid procedure since surgery (together with other complementary therapies), is still today the best treatment in forms with anterior evolution.

Aged↗
PubMed1995

[Traumatic rupture of the chordae tendineae in acute tricuspid insufficiency. Early detection with transesophageal echocardiography].

An uncommon case of traumatic rupture of chordae tendineae with tricuspid regurgitation is described. The early diagnosis, in a patient with polydistrectual injuries, was done by transesophageal echocardiography. This technique allowed accurate diagnosis of the type of lesion suggesting the opportunity to perform an echocardiogram, possibly transesophageal, in all patients with blunt thoracic trauma, even in the absence or with subtle clinical manifestations of cardiovascular involvement.

Accidents, Traffic↗
PubMed1994

No apparent involvement of the FMR1 gene in five patients with phenotypic manifestations of the fragile X syndrome.

Most fragile X patients have a significant increase in the number of CGG repeats in the FMR1 gene. Two patients were described with a deletion and one patient with a point mutation in the FMR1 gene. We describe 5 patients with a fragile X or Martin-Bell phenotype. Two brothers were discordant for the region containing the FMR1 gene; if there is a common cause for the mental retardation this is not located in the FMR1 gene. In the other 3 patients the expression of the FMR1 gene was found to be normal and no abnormalities were noted in the FMR1 mRNA. No amplification was found in the GCC repeat which is associated with the fragile site FRAXE. We conclude that the Martin-Bell phenotype can also be caused by mutations outside the FMR1 gene.

Child↗
PubMed1994

Butyrate and acetyl-carnitine inhibit the cytogenetic expression of the fragile X in vitro.

Cytogenetic expression of the fragile site at Xq27.3 is only found in those patients who have a full mutation of the FMR1 gene, i.e., a large amplification of the CGG repeat. However, an expansion of this repeat, although necessary, does not seem to be sufficient to cause expression of fra(X)(q27.3). Other factors are clearly needed, e.g., thymidylate stress. Little or no attention has been paid to the possible role of histones in the expression of the fragile sites, in spite of their structural and regulatory role in the chromatin complex. Histones can be modified by treating intact cells in vitro with butyrate, a substance that causes histone acetylation. The purpose of the present work is to test the effect of butyrate and of the acetylating compound acetyl-L-carnitine on the expression of fra(X)(q27.3) by treating peripheral lymphocytes of fragile X syndrome patients with these substances in vitro. We show that this treatment causes a significant inhibition of fra(X)(q27.3) expression.

Acetylation↗
PubMed1994

Unstable triplets and their mutational mechanism: size reduction of the CGG repeat vs. germline mosaicism in the fragile X syndrome.

The mechanism responsible for the characteristic expansion of the trinucleotide repeat involved in the pathogenesis of the fragile X syndrome is still largely unclear. Slipped strand mispairing (SSM) and similar DNA replication errors could determine both increases and decreases of the unit number in simple repetitive sequences. Actually, there have been a few reports of size reduction of the (CGG)n in parent-to-child transmission of the fragile X syndrome, which may help in understanding the mutational mechanism and may have practical implications for genetic counseling. We describe here 5 such cases from our series of fragile X patients and emphasize the possible role of SSM-like events in causing (CGG)n expansions and reductions. The possibility that some of these reductions are only apparent, resulting from parental germinal mosaicism is also considered.

Base Sequence↗
PubMed1994

XLMR genes: update 1994.

We provide a comprehensive list of all known forms of X-linked mental retardation. It comprises 127 entries, subdivided into 5 categories (syndromes, dominant disorders, metabolic disorders, neuromuscular disorders, and nonspecific mental retardation). Map location of 69 putative loci demonstrates several overlaps, which will only be resolved by more refined mapping or cloning of the respective genes. The ultimate goal of identifying all the genes on the X chromosome whose mutations cause mental retardation will require a concerted effort between clinical and molecular investigators.

Chromosome Mapping↗
PubMed1994

Identification of key recombinants in multiplex SMA families.

Recent reports have provided evidence that a major gene for autosomal recessive proximal spinal muscular atrophy (SMA) resides in a small genetic interval in bands q12-q13 of chromosome 5, a 4-cM region proximally flanked by D5S125 (EF(TG/AG)n) and distally by MAP1B/D5S112 or a 0.7-cM interval (range 0.1-2.1 cM) flanked by D5S435 proximally and MAP1B/D5S112 distally. We present the identification of key recombinants between SMA and the closest flanking DNA-markers in an analysis of Dutch and Italian SMA families. These crossovers may serve as reference points for new markers in this region and may thus be instrumental in a further refined mapping of the SMA gene. Two markers, D5S351 (I105) and D5S357 (Mfd151), could be mapped distally to SMA in the interval SMA-D5S112.

Chromosome Mapping↗