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G Simoni

Publications and source records attributed to G Simoni.

At least 73 records · Page 4Linked to original sources
PubMed1992

Extravillus dividing fetal cells at CVS: evidence of their erythroblastic origin.

Cytological and cytogenetic studies were performed on nucleated fetal cells present in chorionic villus transport medium. The erythroblastic origin of these cells was shown. Fetal erythroblasts in spontaneous mitosis were frequently observed; chromosome counts were obtained from them but poor quality often prevented banded analysis. Cytogenetic study of erythroblast metaphases can be useful as an additional diagnostic aid in cases of mosaicism with aneuploid cell lines.

Amniotic Fluid↗
PubMed1992

Cyclophosphamide increases the frequency of sister chromatid exchange in direct preparations of human chorionic villi in the absence of supplementary enzymatic activation systems.

A study was performed to evaluate the effect on the frequency of sister chromatid exchange in first trimester chorionic villi of two chemical compounds, mitomycin C and cyclophosphamide. Mitomycin C is generally known to induce an increase in sister chromatid exchange both in vivo and in vitro standard conditions. Cyclophosphamide is a compound requiring additional enzymatic enrichment of the culture medium to express its mutagenic activity under in vitro conditions. We exposed chorionic villi samples to these chemicals without the use of conventional cell cultures and without adding enzymatic extracts to the medium. The results indicate a statistically significant increase in the frequency of sister chromatid exchange after exposure to both compounds and also at lower dosages.

Biotransformation↗
PubMed1992

Trisomy 16 confined to chorionic villi and unfavourable outcome of pregnancy.

Two cases of trisomy 16 confined to placental tissue associated with an unfavourable outcome of the pregnancy are reported. In the first case, after a diagnosis of an apparent non-mosaic trisomy 16 at chorionic villi sample (CVS), an intrauterine fetal death occurred at the 22nd week. In the second case a mosaic with trisomy 16 was found in chorionic villi and the fetus was still-born at 38 weeks. From a comparison of their cases with those of the literature, the authors conclude that a trisomy 16 confined to placental tissue has a negative effect on fetal growth and pregnancy outcome.

Adult↗
PubMed1992

[Termino-terminal arteriovenous fistula at the anatomic snuffbox for chronic hemodialytic treatment].

Between January 1979 and December 1989, an end-to-end arteriovenous fistula for chronic haemodialysis was performed at the anatomical snuffbox (AVF-AS) in 140 patients (49 females and 91 males) with mean age 51 years (range 14-81) referred to our Center from 12 different Hospitals. The choice of the site, on the non dominant arm, depends on the characteristics of the vessels and on the arterial blood pressure. No operative mortality no major complications occurred no distal symptoms related to venous hypertension or arterial steal syndrome or ischaemia. The median survival was 36 months with a patency rate of 77.3% at 1 year, 36.3% at 5 and 18.9% at 10 years. The high incidence of thromboses (52.9%) reflects an excessive compliance with this technique and a lack of expertise on the choice of the proper vessels or an inadequate management of the vascular access. Compared to the graft vascular access, the patency rate is superimposable but with higher rate of complications and lower cost-benefit rate for the grafts. In our experience, the AVF-AS should be, whenever possible, the first step as vascular access for chronic haemodialysis, but the surgical procedure should be reserved only to experienced surgeons. It is safe, cheap and allow to save and use for a longer period the patient's own vessels.

Adolescent↗
PubMed1992

[Modification of the in situ saphenous vein technique as vascular access for chronic hemodialysis treatment. Technical note].

A modification of the "in situ" saphenous vein graft above the knee is used to perform vascular access for maintenance haemodialysis when the upper arms are no more suitable. This technique is easy to perform with only one vascular anastomosis and the above knee saphenous vein is entirely available for venipuncture. The possible use of the Fogarty catheter form both sides and the convenient cost-benefit rate make this method indeed interesting.

Arteriovenous Shunt, Surgical↗
PubMed1991

First-trimester genetic diagnosis in multiple pregnancy: principles and potential pitfalls.

Both the principles of first-trimester genetic diagnosis in multiple pregnancy and the special considerations required to avoid potential diagnostic pitfalls are presented. The experience consisted of 65 cases of twins and one case of quadruplets. Dichorionic twins were recognized by sonography in 54 cases. Transabdominal aspiration was generally preferred to transcervical for obtaining chorionic tissue, although in two cases both approaches were used. Diagnostic error following erroneous sampling was reported in 3 out of 54 sets of dichorionic twins (5.5 per cent). When like-sex dichorionic twins cannot be differentiated by cytogenetic or DNA polymorphism studies, amniocentesis should be recommended to confirm the reliability of the result on chorionic tissue.

Adult↗
PubMed1991

Multiple clonal chromosome abnormalities in Peyronie's disease.

Numerical and structural chromosome aberrations were found in cell plaque metaphases from 9 of 14 patients with Peyronie's disease. In two cases there was evidence of clonal evolution for some of the chromosomal aberrations observed. The Y chromosome was the most frequently involved in numerical changes. Four of 9 cases with abnormal karyotype showed more than one abnormal, cytogenetically unrelated clone. Our findings suggest the possibility of a multiclonal origin for this benign tumor, and confirm the presence of chromosome instability in this cell growth disorder.

Adult↗
PubMed1991

Genetic diagnosis before the eighth gestational week.

Transabdominal chorionic villus sampling (CVS) by a freehand, ultrasound-guided technique was offered to 210 high-genetic-risk women at 6-7 weeks' gestation. It was carried out in 201 cases and postponed in nine cases (4.3%). Sampling was successful in 86 and 100% of cases after the first and the second needle insertions, respectively. Chorionic tissue specimens weighed at least 20 mg in 86% of cases, and only 2% were below 10 mg. Early complications were present in 7.9% of cases, apparently without any adverse effect on maternal or fetal outcome. The rate of fetal loss was 3.5%. Genetic diagnosis was concluded in 1-3 days by rapid diagnostic methods. Although more extensive laboratory and clinical experience is necessary to evaluate adequately the safety of early transabdominal CVS, it may be advantageous to offer this technique to certain high-genetic-risk patients. The availability of genetic diagnosis before the eighth week makes clinical abortion by antiprogestins and prostaglandins a viable option in cases of affected embryos.

Adult↗
PubMed1990

[Distal gastrectomy with Y gastroenteroanastomosis not associated with vagotomy in elective surgical treatment of gastroduodenal ulcer. Clinical and functional long-term results].

During the period 1977-1984, 53 patients with peptic ulcer resistant to H2-blockers (29 gastric and 24 duodenal ulcers) were submitted to distal gastrectomy with Roux-en-Y gastroenteroanastomosis not associated with vagotomy. The indication was used as an alternative to proximal vagotomy in cases with delayed gastric emptying, high acid output, perforation or bleeding. The study plan consisted of serial clinical and instrumental controls including determination of basal (BAO) or maximal (MAO) acid output. Operative mortality was nil. At various times after the operation, 4 patients died for unrelated reasons and 3 were lost to follow-up. Median follow-up was 84 months with an interval of from 4 to 137 months. Fifty-one patients were followed up for at least one year and 49 for at least two. Five patients (2 gastric and 3 duodenal ulcers) developed peptic recurrences (Visick IV, 9.8%) by the end of the first postoperative year and, in all cases but one, healed stably by the second year after medical (3 cases) or surgical (1 case) therapy. In the remaining patients, Visick was grade III in 6 cases (4 gastric and 2 duodenal ulcers), grade II in 6 and grade I in 34. Before operation, mean values (+/- SD) of BAO and MAO were respectively 5.84 +/- 5.03 and 29.6 +/- 18.6 mEq/h. In the immediate postoperative period there was a considerable reduction in BAO (p less than 0.02) and MAO (p less than 0.03) which continued up to the third postoperative year with a tendency to further progressive reduction in MAO. In spite of a considerable individual variability in dimensions and temporal evolution, the phenomenon occurred qualitatively in all cases. No significant difference was observed in the behaviour of BAO and MAO in gastric ulcers by comparison with duodenal ulcers and in cases with recurrence and Visick III compared to those with a favourable clinical result.

Adult↗
PubMed1990

Direct chromosome preparation and culture using chorionic villi: an evaluation of the two techniques.

We present a comparison between direct chromosome preparation and cell culture for first trimester fetal chromosome study using chorionic villi. The 2 techniques have advantages and disadvantages and are demonstrated to be appropriate for routine diagnostic work. The combined use of both methods may optimize the quality of the chromosome study and minimize the possibility of false-positive and false-negative findings.

Cells, Cultured↗
PubMed1990

Sister chromatid exchanges in first-trimester chorionic villi after in vivo and in vitro exposure to diagnostic ultrasound.

A study was done to evaluate the effects of diagnostic ultrasound on sister chromatid exchange (SCE) in first-trimester chorionic villi under controlled technical conditions. Chromosome analysis was performed by the direct method using spontaneous mitoses from the cytotrophoblast layer, and SCE visualization was accomplished by a 72 h treatment with 5-bromodeoxyuridine (BrdU) at a concentration of 10 micrograms/ml. The slides were stained with acridine orange. Immediately before first-trimester chorionic villus sampling, a group of ten pregnant women was exposed to diagnostic ultrasound for 20 min (in vivo exposure). This group of patients was compared with a control group who were not exposed. A mean value of SCE/cell frequency of 4.2 +/- 0.2 was found in the exposed pregnancies, while a value of 3.7 +/- 0.2 was observed in the control group. After in vitro exposure of chorionic villi obtained from elective abortions, the frequency of SCE/cell did not differ significantly among samples with different exposures (1, 2, and 3 h) and controls. The positive control (mitomycin C) yielded a significant increase in SCE frequency.

Chorionic Villi↗
PubMed1990

Five years' experience with Hickman catheters as temporary access for haemodialysis.

Two different types of Hickman catheters were used as central venous access for haemodialysis. The device was implanted in 58 patients with chronic renal failure, already undergoing haemodialysis, because of thrombosis or infection of the previous vascular access, in order to permit immediate treatment and in nine patients with acute renal failure, as a 'first choice' method suitable either for dialysis or for parenteral infusions and nutrition. The catheter was inserted, under local anaesthesia, through the external jugular vein up to the right atrium; the haemodialysis treatment was carried out by single-needle technique 3-4 times weekly and all the catheters were filled daily with heparinised saline and Miconazole solution. The mean duration was 76 +/- 93 days with an overall of 2253 treatments. The flow rate ranged between 150 and 290 ml/min, with acceptable recirculation rate and biochemistry similar to that of standard dialysis. The complication rate was 20%, including thromboses and infections; no operative mortality nor major complications were observed. Based on these data, we believe that the Hickman catheter represents the ideal method of temporary access for haemodialysis.

Adult↗
PubMed1990

12q13 fragility in a family with recurrent spontaneous abortions: expression of the fragile site under different culture conditions.

A fragile site at the 12q13 band was found in metaphases from lymphocyte cultures of three members of a family. A comparison of the frequency and expression of the fragile site was carried out on cells cultured in RPM-I 1640 with and without BrdU and in 199 media. The fragile site was not typically folate-sensitive, being expressed in standard medium as well as in cultures after exposure to BrdU.

Abortion, Habitual↗
PubMed1990

[Post-thoracotomy antalgic treatment].

The goal of this study was to assess the efficacy of a simple technique used for producing analgesia during any thoracic operation. Its principle consists in peroperative local anesthesia of the nervous trunk in the intercostal space exposed by the surgeon. Methods 17 patients had peridural anesthesia via a multi-hole catheter, and received a bolus injection of 1.5 mg/kg of lidocaine, with subsequent continuous drip injections by electric needle, at a rate of 50 mg/hr. Results This treatment induced no side effects. Although not complete, analgesia allowed the patient to cough and expectorate without experiencing pain block. This permits to avoid, to the greatest extent, occurrence of postoperative atelectasia and provides for carrying out very prompt, effective chest physical therapy.

Catheters, Indwelling↗