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Biomedical subjects

L Bianchi

Publications and source records attributed to L Bianchi.

At least 235 records · Page 13Linked to original sources
PubMed1994

Evaluation of serine alpha 1-antitrypsin and polymorphonuclear leukocyte elastase contents and their immunogenetic correlation in psoriasis.

The purpose of our study was to quantify the serum content of alpha 1-antitrypsin (alpha 1-AT) and polymorphonuclear leukocyte elastase (PMN-E) in of 21 patients affected by active and stationary psoriasis, and 12 normal controls. HLA typing was also performed to identify a correlation among HLA antigens, age at onset of psoriasis and biochemical results. alpha 1-AT levels were within the normal range in all patients, even in those with active, extensive, inherited and juvenile psoriasis, and in the controls. These data allow us to exclude, in our patients, the presence of rare or defective phenotypes, frequently associated with reduced serine levels of alpha 1-AT. The PMN-E serine content was greatly increased in 3 patients, increased in 2, and slightly modified in 6 cases. All patients with the highest PMN-E levels reported a positive family history and absence of pulmonary, hepatic and atopic diseases. An increased psoriatic inheritance has been observed in the CW6-positive subjects (7/20), comparing B13 and DR6 antigen frequency. No correlation among HLA antigens, age at onset, clinical phase, or biochemical results could be established.

Adolescent↗
PubMed1994

NMDA receptor antagonists decrease GABA outflow from the septum and increase acetylcholine outflow from the hippocampus: a microdialysis study.

The modulation of the septohippocampal cholinergic pathway by glutamatergic or GABAergic inputs was studied by monitoring the outflow of ACh collected via a transversal microdialysis probe implanted into the hippocampus and other brain areas of freely moving rats. In one set of experiments a transversal microdialysis membrane was inserted in the dorsal hippocampus, drugs were administered intracerebroventricularly through a cannula implanted in the lateral ventricle, and ACh outflow in the dialysate was measured by an HPLC method with an electrochemical detector. The dialysis membrane was usually perfused with Ringer's solution containing 7 microM physostigmine sulfate. Intracerebroventricular injections of the NMDA antagonists 3-((RS)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP; 1-50 nmol), MK801 (0.5-20 nmol), and D(-)-2-amino-7-phosphonoheptanoic acid (100 nmol) brought about an increase in hippocampal ACh outflow while the non-NMDA antagonist 6,7-dinitroquinoxaline-2,3-dione (0.25-20 nmol) was without effect. The increase in ACh outflow following CPP administration was dose dependent and reached a maximum of about 500%. It was abolished by TTX (0.5 microM) delivered locally to the hippocampus via the dialysis membrane and prevented by intracerebroventricular injection of the GABA agonist muscimol (5 nmol). In a second set of experiments, one microdialysis membrane was inserted in the dorsal hippocampus to detect ACh outflow and another in the septum to administer drugs locally and at the same time detect septal GABA outflow. The septal dialysis membrane was perfused with Ringer's solution without physostigmine, and GABA levels in the dialysate were measured by an HPLC method with a fluorescence detector. CPP (100 microM) perfused through the septum resulted in a decrease in septal GABA outflow and a concomitant increase in hippocampal ACh outflow. Muscimol (100 microM) administration into the septum abolished the effect of CPP on hippocampal ACh outflow but did not affect septal GABA outflow. These results demonstrate that in the septum NMDA receptors tonically activate GABAergic neurons which in turn inhibit the cholinergic septohippocampal neurons.

2-Amino-5-phosphonovalerate↗
PubMed1993

[Portal venous thrombosis following splenectomy in portal hypertension: risks and management].

Splenectomy intended to treat hypersplenism can, in the presence of portal hypertension (PTH), lead to extrahepatic portal and mesenteric vein thrombosis. The management of possible variceal bleeding in patients with extrahepatic portal vein occlusion following splenectomy in portal hypertension is a problematic and challenging undertaking. We report on the management of variceal bleeding in 2 noncirrhotic patients with PTH who developed portal vein thrombosis following ill-advised splenectomy. It must be stressed again that splenectomy alone intended to control hypersplenism in portal hypertension is to be avoided at all costs. Options for the treatment of portal and mesenteric vein thrombosis and variceal bleeding are proposed.

Adult↗
PubMed1993

Ursodeoxycholic acid treatment of primary hepatolithiasis in Caroli's syndrome.

Congenital cystic dilation of the intrahepatic bile ducts (Caroli's syndrome) is a rare cause of chronic cholestasis and hepatolithiasis in young adults. Long-term prognosis is poor even with surgical drainage. We treated twelve patients who had Caroli's syndrome and intrahepatic stones with ursodeoxycholic acid (UDCA), 10-20 mg/kg daily. The duodenal bile of these patients contained cholesterol crystals, which suggests that the stones were cholesterol rich. UDCA led to sustained clinical remission, return to normal liver function, and dissolution of intrahepatic stones on ultrasound in all patients (nine partial, three complete) after 48 (range 12-114) months' follow-up. Litholytic therapy is indicated for intrahepatic stones in Caroli's syndrome.

Adult↗
PubMed1993

Proliferating cell nuclear antigen complex formation induced by ultraviolet irradiation in human quiescent fibroblasts as detected by immunostaining and flow cytometry.

The association of the proliferating cell nuclear antigen (PCNA) to DNA synthesis sites was investigated in human quiescent fibroblasts after UV irradiation. Associated PCNA was detected with the monoclonal antibody (MoAb) PC10 and by immunofluorescence assessment with flow cytometry, after a hypotonic lysis step in order to release unbound molecules. Immunofluorescence levels, relatively low in untreated control cells, increased by about threefold after uv irradiation. The time course of PCNA complex formation showed a maximum after about 30 min from irradiation and was found to be dose-dependent up to about 10 J/m2, after that it reached a plateau. Formation of the PCNA-chromatin complex was neither significantly affected by the topoisomerase II inhibitor VP-16, nor by the poly(ADP-ribose)polymerase inhibitor 3-aminobenzamide. In contrast, a significant reduction was obtained either after ATP depletion or after incubation with the protein-kinase inhibitor staurosporine. Immunoprecipitation studies on nuclear extracts from 32P-labeled cells showed that PCNA bound to DNA synthesis sites was phosphorylated. The results indicate that PCNA associated to DNA repair synthesis sites may be detected with PC10 MoAb after a hypotonic lysis step, and provide evidence that the transition from soluble to chromatin-associated form of the protein is dependent on a phosphorylation mechanism.

Alkaloids↗
PubMed1993

Low-dose interferon in chronic hepatitis non-A/non-B: effects on quantitative liver function and structure in a randomized, controlled multicenter trial.

In this randomized, controlled multicenter trial we evaluated the effects of recombinant interferon-alpha 2b on galactose elimination capacity and histological activity index in 88 patients with chronic active hepatitis non-A/non-B. Forty-five patients were randomly assigned to treatment with interferon at 1.5 x 10(6) U three times per for 1 year; 43 patients were assigned to no treatment. A complete response (normalization of alanine aminotransferase) was observed, respectively, in 47% and 5% of the two groups (P < 0.006); 47% of these patients suffered a relapse. Thus 22% of patients had a sustained response. Histological activity decreased significantly in responders (P < 0.04) while the biopsy score did not change significantly in nonresponders. In contrast, galactose elimination capacity--a surrogate marker for survival in chronic active hepatitis--was not affected by response to treatment. None of the parameters evaluated, including hepatitis C virus RNA, was able to predict response or relapse. We conclude that low-dose interferon treatment for 1 year is as effective as the recommended treatment schedule.

Adolescent↗
PubMed1993

Glycogen storage disease I and hepatocellular tumours.

From 50 published cases of hepatocellular adenoma (HCA) in glycogen storage disease, type I (GSD I) some characteristic features may be deduced: 1. The male:female ratio was 2:1. This sharply contrasts to HCA of other origin which shows a strong female preponderance. 2. The histology of adenomas largely corresponded to other adenomas, except for the appearance of Mallory bodies, accompanied by neutrophilic inflammation and a peculiar lamellar fibrosis. This observation is of particular interest because Mallory bodies have so far not been described in adenomas but are a well established feature in hepatocellular carcinoma of any aetiology. 3. Adenomas had a tendency to regress after continuous nocturnal intragastric feeding, although not all cases responded favourably. 4. Ten cases of hepatocellular carcinoma (HCC) are recorded in GSD I in literature, whereby in half of them transition from HCA into HCC seems likely. 5. The similarity in clinical presentation and evolution with oestrogen-induced tumours is striking. Pathogenesis of adenoma formation in GSD I is not understood. Experimental evidence and the clinical observation of regression after correction of the metabolic imbalance suggest three possible candidate mechanisms: (1) a glucagon/insulin imbalance; (2) cellular glycogen overload; and (3) proto-oncogene activation. Evidence in favour of these three mechanisms from experimental studies and observations in humans are briefly reviewed.

Adolescent↗
PubMed1993

Mutagenic and antimutagenic activities of Uncaria tomentosa and its extracts.

Mutagenic and antimutagenic activities of extracts and chromatographic fractions of Uncaria tomentosa bark are reported. The plant extracts and fractions show no mutagenic effect in different strains of Salmonella typhimurium with and without metabolic activation. However, the plant extracts and fractions show a protective antimutagenic effect in vitro against photomutagenesis induced by 8-methoxy-psoralen (8-MOP) plus UVA in S. typhimurium TA 102. A decoction of U. tomentosa ingested daily for 15 days by a smoker decreased the mutagenicity induced in S. typhimurium TA98 and TA100 by the subject's urine.

Adult↗
PubMed1993

Flow cytometric analysis of DNA sensitivity to nuclease S1 in UVC-irradiated human fibroblasts.

The sensitivity of human fibroblast DNA towards the activity of nuclease S1 was investigated in situ after irradiation of the cells with UVC light. DNA digestion was assessed using flow cytometry by staining the nuclease-resistant DNA fraction with the specific fluorochrome propidium iodide (PI). The results showed a non-linear dependence of DNA digestion on the UVC irradiation dose between 0 and 20 J m-2. About 70% of the UVC-induced DNA sensitivity to nuclease S1 was lost after 30 min of repair. These results suggest that flow cytometry may be useful for assessing the heterogeneity of cell response to UV damage.

Cells, Cultured↗
PubMed1993

The common pattern of cytokeratin alteration in alcoholic and cholestatic liver disease is different from that of hepatitic liver damage. A study with the panepithelial monoclonal antibody lu-5.

The patterns of cytokeratin as determined by murine monoclonal antikeratin antibody lu-5 (mAb lu-5) were quantitated in paraffin-embedded liver tissue from normal and diseased subjects. In tissue from healthy medical students, mAb lu-5 was found to decorate 2-4 periportal and 2-3 perivenular cell layers. Alcoholic liver disease was accompanied by a marked increase in intensity of mAb lu-5 antigen expression in zone I and III hepatocytes. Moreover, additional liver cells of both zones were progressively recruited, so that in advanced lesions all three lobular zones became positive. In mechanical as well as in drug-induced cholestasis, a similar increase of mAb lu-5 antigen expression was already observed in earlier stages of disease, including an earlier recruitment of zone II hepatocytes. In both alcoholic and cholestatic biopsies the intensity and extent of mAb lu-5 epitope expression increased with the duration and severity of disease. In primary biliary cirrhosis (PBC) and seemingly also in primary sclerosing cholangitis the increase and extent was more marked in zone I, the zone of assumed cholate accumulation. Changes in zone III, the territory of histologic cholestasis (bilirubinostasis), became evident only in late stages of PBC. Mallory bodies of alcoholic and cholestatic liver disease showed an identical mAB lu-5 antigen expression, thus giving rise to four different staining patterns. Changes of cytokeratin expression are similar in alcoholic and cholestatic liver diseases. In chronic viral hepatitis, however, cytokeratin alterations are discrete and restricted to precirrhotic/cirrhotic stages.

Antibodies, Monoclonal↗
PubMed1993

Involvement of proliferating cell nuclear antigen in DNA repair after damage induced by genotoxic agents in human fibroblasts.

The association of the proliferating cell nuclear antigen (PCNA) to DNA synthesis sites during the process of DNA repair, was investigated in human diploid fibroblasts after treatment with different genotoxic agents. For this purpose, confluent cultures were treated with agents that form primarily DNA adducts, such as u.v.-C, 8-methoxypsoralen (8-MOP) and 4,4',6-trimethylangelicin (TMA), or with agents that induce strand breaks, such as X-rays or bleomycin (BLM). Chromatin-associated PCNA was detected with a monoclonal antibody and indirect immunofluorescence labelling. Quantitative analysis was performed by flow cytometry. Not all of the tested agents were able to activate the association of PCNA with chromatin. X-rays, u.v.-C and BLM induced a significant increase in PCNA complex as compared to the control samples. In contrast, 8-MOP and TMA did not show any detectable effect on the levels of associated PCNA, even at post-incubation repair times as long as 10 h. However, these drugs damaged DNA, as shown by the formation of micronucleated cells 48 h after treatment. The lack of PCNA activation was not due to an inhibition of the repair mechanism, since in TMA-treated fibroblasts, subsequent irradiation with u.v.-C induced an increase in PCNA levels comparable to that found in cells treated with u.v.-C alone. These results indicate that PCNA is involved in DNA excision repair of genotoxic agents, but suggest that similar types of lesions may be repaired with alternative pathways not requiring PCNA.

Bleomycin↗
PubMed1993

Oocyte donation: comparison between recipients from different age groups.

Oocyte donation was carried out in 87 patients in 141 replacement cycles. These patients received oocytes from 108 women undergoing assisted reproductive technology procedures at our centre. Standardized hormonal replacement therapy and in-vitro fertilization procedures were performed. We divided recipients into four groups according to their age (group A, 21-35 years; B, 36-40 years; C, 41-49 years; and D, 50-61 years). Oocytes donors were 21-35 years old, and equally spread across these different age groups. There were significant differences in the pregnancy and implantation rates according to the age of the recipients; which were 45% and 23% respectively in women 21-35 years old (group A) versus 23% and 10% in women 41-49 years old (group C). A comparison of data between oocyte donors and young recipients, with similar results in donors and young recipients, with pregnancy rates of 45% and 42% and implantation rates of 23% and 19.5% respectively. Statistically significant differences were found between donors and the older recipients, pregnancy rates being 43% versus 23%, and implantation rates 18% versus 10%. These data seem to demonstrate a lesser likelihood of pregnancy and implantation in older recipients because of increasing uterine age.

Adult↗
PubMed1993

Influence of spermatozoa characteristics on gamete intra-fallopian transfer procedures: analysis of results obtained utilizing normozoospermic, oligoasthenozoospermic and donor spermatozoa.

The objective of this study was to analyze the efficacy of the gamete intra-Fallopian transfer (GIFT) procedure in relation to spermatozoa characteristics. A total of 268 infertile couples enlisted for GIFT were categorized into three groups on the basis of semen characteristics in the husband. These included oligoasthenozoospermic men in 88 retrieval cycles (group 1), normozoospermic men in 116 cycles (group 2) and azoospermic partners who needed donor semen in 86 cycles (group 3). All female patients had ovarian stimulation and laparoscopic GIFT. Pregnancy rates were significantly higher with donor spermatozoa than with oligoasthenozoospermic or normozoospermic spermatozoa, i.e. 51.1% versus 15.9% (P < 0.001), and 32.7% (P < 0.005). Implantation rates were significantly higher with donor spermatozoa than with normo- or oligoasthenozoospermic spermatozoa (P < 0.01). These data suggest that GIFT does not give good results with male factor infertility. Donor cryopreserved semen gives higher pregnancy and implantation rates than normozoospermic semen, and GIFT with donor spermatozoa gives a good chance of pregnancy to couples previously treated with artificial insemination using donor semen.

Female↗
PubMed1993

Pachyonychia congenita with late onset of nail dystrophy--a new clinical entity?

Pachyonychia congenita syndrome (PCS) is a genetic disease with an autosomal dominant mode of transmission in which the main sign, pachyonychia, usually arises at birth or in childhood together with other disorders of keratinization. A 28-year-old woman developed subungual hyperkeratosis of all toe-nails and thumb-nails associated with pain on pressure and walking. She had a scrotal tongue with leucokeratotic areas, blister formation, plantar hyperkeratosis, palmoplantar hyperhidrosis and dental cavities since childhood. The present case, interpreted as PCS of late onset, could be a clinical variant of the Jadassohn-Lewandowsky syndrome with the late onset of pachyonychia or else an additional form of PCS due to the expression of a new and different allele.

Adult↗
PubMed1993

Allergic contact dermatitis of the lip margins from para-tertiary-butylphenol in a lip liner.

We describe the use of gas chromatography with mass spectrometry (GC-MS) in the investigation of a case of allergic contact dermatitis of the lip margins caused by a lip liner. Patch testing identified sensitization to para-tertiary-butylphenol-formaldehyde resin (PTBP-FR), a resin glue frequently used in leather work but rarely found in cosmetics. Investigation specified the para-tertiary-butylphenol (PTBP) component of the resin as the hapten responsible for the allergic contact dermatitis, as well as for associated depigmentation.

Adult↗
PubMed1993

Sonographic diagnosis and hemodynamic correlation in veno-occlusive disease of the liver.

This study evaluated the role of duplex Doppler sonography in the diagnosis of VOD of the liver after bone marrow transplantation. Sixteen patients with clinical criteria of VOD were studied. The final diagnosis was achieved by transjugular liver biopsy, and the hepatic venous pressure gradient was measured during the procedure to estimate portal pressure. Nine patients (56.2%) had histologically proved VOD. Gallbladder wall thickening was present in 75% of patients with VOD, but in none of those without it (P = 0.01). Gallbladder wall thickening and ascites were present only in patients with portal hypertension. Nine patients (five with VOD and four without it) also were evaluated with duplex Doppler sonography, and no obvious flow abnormalities were detected in the portal vein and hepatic veins. These results suggest that sonography is useful in detecting early signs of portal hypertension pointing to the diagnosis of VOD in patients with bone marrow transplantation.

Adolescent↗