Search PubMed⌕ Search

Biomedical subjects

M Colombo

Publications and source records attributed to M Colombo.

At least 253 records · Page 14Linked to original sources

Intrahepatic doxorubicin in unresectable hepatocellular carcinoma. The unfavorable role of cirrhosis.

To investigate the relationship between the presence of cirrhosis and the antitumor effects of locoregional chemotherapy with doxorubicin, 16 patients with nonresectable hepatocellular carcinoma (HCC) and satisfactory baseline clinical conditions (Child class A or B, Karnofsky index greater than 70%) were studied. Eight patients had post-necrotic cirrhosis, five had serum HBsAg. The dose of doxorubicin was 0.3 mg/kg body weight/day, given by continuous intracoeliac infusion for 8 consecutive days. Eight patients (six with cirrhosis) died prematurely after the first course of chemotherapy. Six (2 with cirrhosis) responded to therapy; they survived 3-33 months (median: 10). In these patients, the type and severity of drug-related side effects were comparable to those reported for patients treated by intravenous chemotherapy. The implication that in many patients with cirrhosis intrahepatic chemotherapy with doxorubicin may hasten death, lessens our interest in its use for nonresectable HCC. In fact, in Italy these cancers frequently occur in association with cirrhosis.

Aged↗

Acute hepatitis B in children with papular acrodermatitis.

Thirteen children who had repeated liver biopsies over a period of 2-16 years after the onset of papular acrodermatitis (PAC) were studied retrospectively. Six patients, rebiopsied within 36 months after the onset of PAC, had histologic evidence of chronic periportal hepatitis. However, repeated biopsies in 3 of the patients revealed a normal liver or chronic portal hepatitis. Whereas all patients had at the end of the observation markers of hepatitis B virus infection, 8 of the 10 patients studied had HBs antigenemia. These data indicate that severe active liver disease may regress without treatment in patients who have had PAC. However, the high frequency of a chronic HBsAg-carrier state among these patients suggests either an inefficient clearance of the virus or an altered immune reaction.

Acrodermatitis↗

Varying nuclear staining intensity of hepatitis B virus DNA in human hepatocellular carcinoma.

An in situ hybridization technique with biotinylated hepatitis B virus (HBV)-DNA probes was used to localize HBV-related DNA sequences in cells of human hepatocellular carcinoma (HCC). Formalin fixed, paraffin-embedded liver biopsies of 11 patients with HCC studied; nuclear HBV-DNA hybridization was observed in 7 of the patients. Sensitivity and specificity of the method were determined by examining appropriate controls. The number of cells exhibiting nuclear fluorescence and intensity of fluorescence varied from tumor to tumor. In two instances liver tissue adjacent to HCC exhibited nuclear staining. HBV-DNA nuclear staining did not correlate with tumor localization of HBsAg or HBcAg, nor with type or with differentiation of the tumor. The use of biotinylated HBV-DNA probes offers a powerful and reproducible technique to localize HBV-related DNA sequences even in formalin-fixed, paraffin-embedded tumor tissue, and also to compare the presence of HBV-DNA with that of viral antigens stained in parallel sections. The frequent localization of HBV-DNA in nuclei of HCC cells fortifies the important epidemiologic association between infection and HCC. The random cellular localization of HBV-DNA sequences in HCC suggests that HBV-DNA may be incorporated, or perhaps replicated, unequally in tumor cells.

Adult↗

Pharmacological properties of droxicam, a new non-steroidal anti-inflammatory agent.

Droxicam showed high antiinflammatory activity in carrageenin-induced edema in rat. At doses of 0.25 and 0.5 mg/kg, droxicam was as active as piroxicam and more active than phenylbutazone given at 2.5 and 5 mg/kg. Against nystatin-induced edema, droxicam (ED50, p.o., 5, 6, 7, 8 h: 7.5, 12.9, 4.8, 8.4 mg/kg) was 4-11 times more active than phenylbutazone and more than 12 times more active than isoxicam. In cotton pellet-induced granuloma in rats, title compound was as active as suprofen. In U.V. light-induced erythema in guinea pigs, droxicam (ED50, p.o., 1, 2, 3, 4 h: 0.51, 0.94, 1.56, 4.88 mg/kg) was 5-9 times more active than phenylbutazone. At doses of 0.1, 0.33 and 1.0 mg/kg/day, droxicam, similar to piroxicam, showed good antiarthritic activity in rats injected with Mycobacterium butyricum against primary and secondary lesions. Droxicam demonstrated strong analgesic activity in protecting against writhings: induced by phenylbenzoquinone in mice: ED50: droxicam = 5.3, phenylbutazone = 61.5, acetylsalicylic acid = 90.7, dipyrone = 83.6, isoxicam = 88.3 mg/kg, p.o.; induced by acetylcholine bromide in mice: ED50: droxicam = 1.1, phenylbutazone = 32.1, acetylsalicylic acid = 32.2, isoxicam = 32.7 mg/kg, p.o.; induced by acetic acid in rat: ED50: droxicam = 0.94, acetylsalicylic acid = 8.72, isoxicam = 4.70 mg/kg, p.o. Antipyretic activity of title compound was demonstrated in rats with pyresis induced by brewer's yeast, being 4-13 times more active than dipyrone. In pyresis induced by Salmonella typhi, droxicam was more active than acetylsalicylic acid and 4-aminoantipyrine at all times and doses. In a study of protection against diarrhea induced by castor oil in rats, droxicam and piroxicam showed equal activity (ED50 = 0.081 and 0.079 mg/kg, p.o., respectively) and were 3.9 and 15.6 times more active than isoxicam and phenylbutazone, respectively. Droxicam significantly inhibited peritoneal capillary permeability in mice at a dose of 5 mg/kg, p.o., while isoxicam and phenylbutazone required 100 and 200 mg/kg, p.o., respectively. Droxicam did not exhibit uricosuric activity in rats. It did not show cardiovascular or respiratory effects in anesthetized cats, nor modify their response to administration of acetylcholine, norepinephrine and histamine. In the Irwin's test, droxicam did not alter rat behavior (80 mg/kg, i.p.) nor that of mice (160 mg/kg, p.o.). Induction of gastrointestinal injuries in rats by droxicam was 10 times less than by piroxicam (UD50: droxicam, 57 mg/kg, p.o.; piroxicam, 5.6 mg/kg, p.o.). The potentiation of gastric injuries induced by stress through cold in rats was also studied.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Fibronectin patterns in hepatocellular carcinoma and its clinical significance.

Fibronectin, a high molecular weight glycoprotein component of the extracellular matrix, was localized extracellularly and intracellularly in the nuclei and the cytoplasm of hepatocellular carcinomas (HCC) by the use of the biotin-avidin method on paraffin-embedded, pepsin-treated tissue. The specificity of the staining was confirmed by absorbing the antibodies with purified fibronectin. Twenty HCC were investigated (7 were autopsy specimens and 13 biopsy and surgical specimens). The fibronectin was either increased or decreased. When increased the fibronectin consisted of thin or thick feathery strands and was either pericellular, sinusoidal, periglandular, or stromal. Marked increase of fibronectin was seen in fibrolamellar HCC, clear cell HCC, and encapsulated HCC, correlating with the better prognosis. Decreased fibronectin was seen in two undifferentiated HCC. HCC obtained at autopsy displayed nuclear and cytoplasmic fibronectin staining. Nuclear fibronectin may be an expression of the DNA binding ability of fibronectin which becomes demonstrable in cells with increased membrane permeability.

Carcinoma, Hepatocellular↗

Transmission of non-A, non-B hepatitis by heat-treated factor VIII concentrate.

In-vitro and animal studies have shown that viral agents can be removed from or inactivated in clotting factor concentrates by physical or chemical treatment. However, clinical data have as yet not substantiated the results of these studies. 13 haemophilia A patients who had not been treated previously with blood or blood products were given a dry-heated factor VIII concentrate and were tested serologically over the next 12 months. Hepatitis developed in 11 patients (84%) and was invariably of type non-A, non-B. Morbidity was not related to the lot of the therapeutic material or to the number of infusions. The incubation period was either 5 or 8-11 weeks, and only 1 patient had symptoms. Aminotransferase elevation showed both monophasic and biphasic patterns. During the follow-up period signs of the disease disappeared in 10 patients (90%). These findings contrast with the absence of non-A, non-B hepatitis in chimpanzees given the same heated concentrate. Thus, clinical studies in first-exposure haemophiliacs are essential for the true evaluation of the safety of new "treated" concentrates.

Adolescent↗

[Orgotein iontophoresis in the therapy of induratio penis plastica].

In objective terms the results of medical and physical treatment of Peyronie's disease are still indubitably disappointing. However personal experience has shown that medicated ionophoresis using orgotein does at least eliminate or reduce the pain in Peyronie's disease.

Administration, Topical↗

New control elements of bacteriophage T4 pre-replicative transcription.

Bacteriophage T4 pre-replicative genes are transcribed, by Escherichia coli RNA polymerase, in two alternative modes: an early mode and a middle mode. Middle mode transcription is under the control of at least one viral protein, pmotA. We have identified two additional viral genes, motB and motC, that map in the dispensable region of the T4 genome, between genes 39 and 56. pmotB and pmotC are diffusible factors which provide an alternative to the motA dependent mode of middle transcription of many T4 genes. Deletions of motB and motC are in fact lethal only in combination with a motA mutant. motB controls one of the alternative modes of transcription of the rIIA gene. When motA or motB are missing, transcription of rIIA is quantitatively unaffected; when both are missing the transcription rate drops by about 75%. Control of transcription of the tRNA gene cluster is more complex. Transcription of subcluster 2 is maximally reduced (70%) only by deletions that, besides motB, cut out an adjacent region. We guess that this adjacent region codes for an additional control element, which we call motC. The motB gene is situated in a 750-base region between the left end-points of del(39-56)-1 and -4.

Genes, Regulator↗

Dendritic development in the neocortex of adult rats subjected to postnatal malnutrition.

The Golgi-Cox method was used to study the maturation of the large pyramidal cells of the Vth cortical layer in two groups of adult rats, one subjected to early postnatal malnutrition and another malnourished only during the second month of life. The main alterations were observed in the pyramidal cells of cortical layer V of rats malnourished during the first month of life. They consist of a decrease in the number and span of dendritic basilar processes. In animals malnourished during the second month of life, the number and span of basilar dendritic processes in pyramidal cells of layer V, were normal. It is postulated that early postnatal malnutrition induced immediately after birth, profoundly disturbs the process of neuronal maturation in the neocortex of the rat brain, probably with permanent effects.

Age Factors↗

Extent and limits of the matching concept in monkeys (Cebus apella).

In Experiment 1, 8 monkeys, experimentally naive with regard to visual stimuli, were trained on identity matching with a two-sample set based on two-dimensional stimuli. On a subsequent test employing two new samples, 4 of the 8 applied the matching rule to the new sample stimuli (as defined by our transfer criterion), and 3 showed substantial savings in learning to match the new samples. Two of these 3 transferred the matching rule when given a second test with two new samples, and the third showed immediate and complete transfer when tested with a third pair of new stimuli. These results indicate a much stronger representation of the matching concept in monkeys than in pigeons, even when the conditions of assessment are reasonably comparable. In Experiment 2, however, 4 monkeys from Experiment 1 failed to transfer the matching rule to steady versus flashing green samples, indicating that the matching concept did not immediately extend beyond the general class of visual stimuli with which it was developed. These and related results in the literature suggest that representation of the matching concept in animals varies along a specificity-abstractness dimension, reflecting the degree to which the concept is tied to the conditions and context of its development.

Animals↗

The significance of protein C antigen in acute and chronic liver biliary disease.

Protein C, a naturally occurring inhibitor of blood coagulation, was measured immunologically in 160 patients with acute and chronic liver and biliary disease. In 31 patients with acute viral hepatitis serially studied from admission to discharge from hospital, protein C antigen (PC:Ag) was low on admission in a high proportion of cases (61%) but became normal in 90% of them after two weeks at a time when the prothrombin time was still prolonged in 46% of the cases. PC:Ag was also low in 25 cirrhotic patients and in 20 patients with chronic active hepatitis. In chronic hepatitis and cirrhosis, PC:Ag levels significantly correlated with indexes of liver synthetic function. In primary biliary cirrhosis (n:40), PC:Ag was low in patients with advanced disease (stages III-IV) but high in the early phases, when cholestasis was not yet accompanied by impaired protein synthesis. PC:Ag was also very high in 20 patients with large bile duct obstruction and highly correlated with indexes of cholestasis. The authors' findings indicate that PC:Ag is reduced in liver disease proportionally to the impairment of the liver synthetic function and that its normalization after acute hepatitis might represent an early marker of recovery of this function.

Acute Disease↗

Hepatocellular carcinoma in Italy: report of a clinical trial with intravenous doxorubicin.

Sixty-six patients with hepatocellular carcinoma (HCC) in various stages of hepatic involvement were studied prospectively. Of these, 50 (75%) had associated cirrhosis and 19 (28%) had serum hepatitis B surface antigen (HBsAg). Six (9%) patients were eligible for tumor resection, 34 were selected for doxorubicin chemotherapy (60 mg/m2, i.v., given every 3 weeks, up to a maximum dose of 550 mg/m2), and 26 were followed up without treatment. Untreated patients survived 1-18 months (median 1) after diagnosis. Surgically treated patients survived 1-14 months (median 4.5). In the doxorubicin group, six patients died soon after the first course of treatment, leaving 28 patients to be evaluated. Seven (24.5%) responded to therapy, surviving 2-26 months (median 8.0). Twenty-one (75.5%) did not respond to chemotherapy and had a median survival of 3.5 months (range: 2-12). Initial performance status and the degree of hepatic impairment were found to be covariates of prognostic significance. The type and severity of drug-related side-effects appeared to be comparable to those reported by others. In accordance with previous reports, our patients with HCC often had non-resectable tumors or responded poorly to chemotherapy. The association between this tumor and cirrhosis might partially account for treatment failure.

Adult↗

[The Sceptor system: relation of results from antibiograms in diffusion agar to MIC].

The Sceptor system and the susceptibility of Gram-positive cocci and Gram-negative rods to several antibiotics were presented. The accuracy of methicillin and gentamicin MIC of Staphylococcus aureus was determined. The MIC of methicillin-resistant strain was less than 8 mg/l. Finally the MIC accuracy to 29 Pseudomonas aeruginosa strains was compared with the results obtained by the standard disk diffusion method.

Diffusion↗