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C Meli

Publications and source records attributed to C Meli.

At least 37 records · Page 2Linked to original sources
PubMed1993

Cytogenetic effects of benzimidazoles in mouse bone marrow.

The cytogenetic effects of three benzimidazoles, i.e., benomyl, methyl thiophanate and methyl 2-benzimidazolecarbamate (MBC), were studied in mouse bone marrow cells by analyzing three genetic endpoints: micronuclei, structural chromosome aberrations plus or minus gaps, and aneugenic effects (hyperdiploidy or polyploidy). In general, the effects were small, but it was observed that benomyl and MBC significantly induced micronuclei as well as aneugenic effects, hyperdiploidy (no metaphases with more than one or two extra chromosomes, 2n + 1 or 2n + 2, were observed) and polyploidy (4n). The induction of chromosome gaps and breaks was less evident. Methyl thiophanate significantly induced micronuclei, but it was less effective than benomyl and MBC. Our results showed that micronuclei are a good indicator of aneugenic effects in mouse bone marrow cells. A curvilinear trend test has been devised to fit the curves originating from the time-dependent responses.

Analysis of Variance↗
PubMed1993

Mutational spectrum of phenylalanine hydroxylase deficiency in Sicily: implications for diagnosis of hyperphenylalaninemia in southern Europe.

Hyperphenylalaninemia due to a deficiency of hepatic phenylalanine hydroxylase (PAH) is the most common inborn error of amino acid metabolism. Clinically, the disorder is highly heterogeneous, spanning from nonphenylketonuria hyperphenylalaninemia to classical phenylketonuria. Only little is known about the molecular defects underlying hyperphenylalaninemia in Southern Europe. In this study, we conducted a systematic analysis of 53 patients from the Sicilian population. Each patient included in the study had persistently elevated blood levels of phenylalanine and met the differential criteria for PAH deficiency. Genomic DNA was analysed by scanning all PAH-coding exons for mutations by PCR in combination with denaturing gradient gel electrophoresis (DGGE). 52 patients were completely genotyped. A spectrum of 40 different mutations was established including 17 novel PAH mutations. Our results explain the clinical heterogeneity of hyperphenylalaninemia in Southern Europe, and form the basis for the establishment of phenotype-genotype correlations in Sicily and surrounding countries.

Alleles↗
PubMed1992

[Ultrasound and color Doppler control of percutaneous angioplasty (PTA) of the renal artery].

The Authors report their experience about fifty patients affected with renovascular hypertension, treated by percutaneous transluminal angioplasty (PTA) for stenosis of main renal artery and now studied by Duplex-Scan and Color-doppler. Results, compared with arterial pressure measurements, renography and laboratory renal function evaluation, showed a sensibility of 84%, specificity of 90% and an accuracy of 87.5%. Advantages and limits of Duplex-scan in patients treated by PTA are briefly discussed.

Angioplasty, Balloon↗
PubMed1991

Neurotransmitter amino acid levels in rat thalamus and cerebral cortex after cerebellectomy.

Glutamate, aspartate, GABA, glycine and taurine levels have been measured in rat thalamus and in cerebral cortex at different time intervals (3rd, 7th, 15th, 30th day) after cerebellectomy. A decrease in glutamate, aspartate and GABA was detected at the 7th day after cerebellectomy in the thalamus and at the 15th day in the cerebral cortex; at the 30th day after cerebellectomy the levels of these amino acids in the thalamus and in the cerebral cortex were observed to have recovered to control values. No statistically significant difference in glycine and taurine levels in the thalamus and in the cerebral cortex after cerebellectomy could be seen. These results show that the functional recovery process after cerebellar injury is associated with a complex modification of amino acid levels in thalamus and in cerebral cortex.

Amino Acids↗
PubMed1991

Inter-laboratory ring trial of in vitro DNA repair tests using rat hepatocytes: further testing and conclusive remarks.

The results of the extension of a collaborative study for the detection of chemical-induced DNA damage in rat hepatocytes in vitro are presented in this report. Three coded compounds, i.e. 1,4-butanediol dimethanesulphonate, hydrazine sulphate and sodium dichromate, were tested for DNA repair synthesis by seven different laboratories, either using autoradiographic procedures or the liquid scintillation counting technique. Inter-laboratory standardization was intentionally not requested in order to investigate the validity of each study design under routine conditions. 1,4-Butanediol dimethanesulphonate was clearly positive in most laboratories; sodium dichromate was generally positive, while the results on hydrazine sulphate were contradictory.

Animals↗
PubMed1991

Alternative methods in toxicology tests: in vitro toxicity.

Toxicity testing is required for new chemicals being introduced onto the market. The use of animals in evaluating chemical safety is costly and time consuming. Furthermore, there is the ethical need to develop alternative methods to reduce the required number of animals. The new in vitro assays offer numerous advantages such as speed, reproducibility and control of test conditions, and increased sensitivity. Although the dermal irritation assays might be substituted by the in vitro tests in the near future (Duffy, 1989), much work is required to evaluate organ toxicity with in vitro methods. We present data regarding the use of Balb/3T3 mice fibroblasts and primary rat hepatocytes as test systems for in vitro toxicity. The end-points we have analysed are total protein content, dye accumulation in lysosomes, reductase mitochondrial activity, intracellular content and leakage of enzymes into the medium.

Animal Testing Alternatives↗
PubMed1991

[The echographic aspects of the splenoportal axis in patients with esophageal varices].

In the present study the A. try to assess the usefulness of ultrasound in detecting blending risk in portal hypertension. Endoscopic and sonographic findings of 35 cirrhotic patients with esophageal varices were compared to a control group of 27 hepatopathy patients without portal hypertension, observed in the same department and in the same interval. The medium caliber of portal vein was 14.64 +/- 2.59 and 11.8 +/- 1.33 mm, respectively in the study and in the control group (p less than 0.01). Statistic correlations were also found in subgroups of patients with varices of different degrees. A portal vein greater than 16 mm was found in 10 of 11 patients with large varices; this pattern provides a sensitivity of 71.4% and a specificity of 94.1%. In our experience this echographic finding should represents a clear indication for close endoscopic follow-up, even in patients without previous bleeding from esophageal varices.

Adult↗
PubMed1989

[Ultrasonography in abdominal emergencies].

From February 1986 to March 1988 113 abdominal US exams were performed in emergency situation to evaluate the accuracy of this methodology: 13 were blunt traumas, 18 postoperative complications. A real-time scanner with a linear probe of 5 MHz was employed. The results were confirmed by surgical and/or clinical and instrumental evaluation. In 81% of the examinations, ultrasonography allowed a diagnosis to be made. Gallbladder and biliary pathologies were the most common findings. The results (sensibility 96%, specificity 88%, accuracy 95%) confirm the reliability of ultrasonography in abdominal emergencies, as shown in literature.

Abdomen, Acute↗
PubMed1987

Intrarectal ultrasonography in the preoperative staging of rectal cancer.

Intrarectal ultrasonography is a new imaging method used in the preoperative staging of rectal cancer. Twenty five patients with proven rectal cancer were submitted to preoperative intrarectal ultrasonography; 24 were resected. Real time scanner with a linear probe of 5 MHz was employed. Five sonographic structures corresponding to the five histological layers were evidenced. Ultrasound T staging was compared to pathology, using UICC classification. In all but two cases pathology corresponded to ultrasound T staging (accuracy 92%). Perirectal nodal involvement was also investigated. It is concluded that intrarectal ultrasonography will play a definite role in the preoperative staging as well as in programming treatment of rectal carcinoma.

Adult↗
PubMed1981

[Bone marrow T-lymphocyte subpopulations in patients with multiple myeloma].

The bone marrow quantitative distribution of the two main T-lymphocyte subsets, recognizable by the "high" and "low-affinity" E-rosette forming cell technique, according to West, was evaluated in ten untreated myeloma patients and twelve normal controls. It was observed, within a normal total T-lymphoid cell count, a significant predominance of the T-lymphocyte subset with "low-affinity" characteristics. An inverse correlation, with statistical significance, between the monoclonal malignant B-component and "low-affinity" T-cell percentage was also seen in all cases. It was suggested, therefore, that such an imbalance between "high" and "low-affinity" T-subsets, with the latter predominating, could play a role in the regulation of the monoclonal B-component growth rate.

Aged↗
PubMedDate not supplied

Activity of 1,2-dimethylhydrazine in the mouse bone marrow micronucleus assay using a triple- and a single-dosing protocol.

In the present study the ability of 1,2-dimethylhydrazine (DMH) to induce micronuclei in mouse bone marrow erythrocytes was investigated using 2 different dosing regimens. DMH caused an increase in micronuclei in both male and female mice following single administration and sampling after 24 h. The effect was more pronounced in female than in male animals. Triple administration of DMH at concentrations corresponding to 80, 40 and 20% of the median lethal dose (MLD) did not increase the incidence of micronuclei in either sex. Small increases in micronucleus incidence were observed after triple dosing at 100% of the MLD value. These results suggest that a future micronucleus protocol should include animals of both sexes and single and repeated administration of the test substance.

1,2-Dimethylhydrazine↗
PubMedDate not supplied

[Megaloblastic anemia: a unusual complication in an infant with double allergy to both cow's milk protein and soy].

The authors reported a case of a child suffering from Cow's milk protein allergy, in which a soybean milk was administered for one month. The incorrect preparation of the formula determined a megaloblastic anaemia due to folate deficiency. The observation of very high levels of seric aminoacids during the acute phase of the disease was noteworthy. The therapy with folic acid and the introduction of protein hydrolysated formula milk determined a rapid normalization of the haematological picture. During the follow-up the administration of soybean protein caused anaphylaxis showing the contemporary presence of soybean allergy. The challenge test with cow's milk performed afterwards showed the restoration of the tolerance towards cow's milk protein.

Anemia, Megaloblastic↗
PubMedDate not supplied

[Genetic role in hernia of the esophageal hiatus. Description of the disease in 2 brothers].

Two brothers born 15 years apart from normal healthy parents were affected by esophageal hiatus hernia diagnosed at 4 and 8 months respectively. We found 37 other families with more than one member affected by EHH reported in the literature. Since the anomaly often runs asymptomatic, familiarity is probably more frequent than generally thought. The type of inheritance is still uncertain, but a multifactorial etiology is the most likely explanation.

Age Factors↗
PubMedDate not supplied

[Neuronal ceroid lipofuscinosis. Description of a case].

The Authors describe a case of Batten-Bielschowsky disease and how they made the diagnosis. It's stressed the importance of the pathological examination, in the absence of any laboratory tests for the diagnosis of this disease.

Cerebellum↗
PubMedDate not supplied

[Role of ultrasonography in emergency surgery].

A prospective study was carried out to compare the value of ultrasound examination with conventional management in patients presenting with emergency surgical problems. During an 4 years period the authors followed 301 patients referred to the Ist Institute of Surgery of the University of Rome "La Sapienza". After immediate clinical evaluation one or more US examinations were performed in each patient following a standard protocol of study. Abdominal emergencies were the most frequent conditions, found in 75% of the cases and the acute abdomen due to trauma in 17.6% of the cases. The overall sensibility, specificity and accuracy of clinical examinations and US examinations were respectively of 88%, 33%, 70% and 95%, 94%, 95%. In 38 patients (12.7%), a diagnosis was made up by sonographic examination which had not been clinically expected (group A). The principal condition in this group was gynaecological pathology, found in 17 patients. In 161 patients (53.3%) sonography confirmed the first diagnosis clinically suspected (group B) and in 23 cases the second or third differential diagnosis (group D). Sonography made no contribution to the diagnosis in 77 cases (25,5%) and only in 2 cases was considered misleading. The result of this study demonstrate the usefulness of emergency ultrasonography in gynecological, gall bladder, pancreatic and vascular diseases. Moreover sonography must be considered the principal diagnostic tool in patients with trauma. In order to recognize gynecological diseases which can simulate appendicitis US examination must be considered necessary in young female patients. When appendicitis is suspected US is useful in children and in older patients too.

Abdomen, Acute↗
PubMedDate not supplied

[Hemorrhagic complication following an external shunt for hemodialysis: a clinical case and a proposed technical procedure for its prevention].

The vascular access for haemodialysis is still a problem not completely solved although surgical experience started more than thirty years ago. Particularly haemorrhagic complications can be dangerous because many patients go home after haemodialysis. The authors report a case in which the disconnection of the conic tip from the shunt cannula for haemodialysis induced an external bleeding, and propose a safety ligature. However, the latter is not necessary for a cannula integrated with the vessel tip.

Aged↗