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Biomedical subjects

C Colombo

Publications and source records attributed to C Colombo.

162 records · Page 9Linked to original sources
PubMedDate not supplied

Sleep phase advance and lithium to sustain the antidepressant effect of total sleep deprivation in bipolar depression: new findings supporting the internal coincidence model?

Recent European studies suggested that sleep phase advance (SPA) could sustain the effects of total sleep deprivation (TSD) both with or without a combined antidepressant drug treatment. Previous studies by our group showed that an ongoing lithium treatment could enhance and sustain the effect of repeated TSD. In the present study we studied the effect of a single TSD followed by 3 days SPA (beginning with sleep allowed from 17:00 until 24:00, with daily shiftbacks of 2 h) in consecutively admitted bipolar depressed inpatients who were taking a chronic lithium salts treatment (n=16) or who were devoid of psychotropic medications (n=14). Changes in mood during treatment were recorded with self administered visual analogue scales and with Hamilton rating scale for depression. Results showed that SPA could sustain the acute antidepressant effect of TSD, and that lithium enhanced the effect of the chronobiological treatment. According to the internal coincidence model, the better clinical effects observed in lithium-treated patients could be due to the phase delaying effect of lithium on biological rhythms, leading to a better synchronization of biological rhythms with the sleep-wake cycle.

Antimanic Agents↗
PubMedDate not supplied

Worsening of delusional depression after sleep deprivation: case reports.

Five patients (three bipolars and two unipolars) affected by a major depressive episode with psychotic features were treated with total sleep deprivation (TSD) without concurrent psychotropic medication. After TSD we observed a worsening in psychotic as well as in depressive symptoms as rated on the Dimension of Delusional Experience Rating Scale and on Hamilton Rating Scale for Depression, respectively. TSD is known to markedly enhance the activity of brain monoaminergic pathways. Given the interaction between brain serotonergic and dopaminergic systems in delusional depression, it is possible that an enhancement in dopaminergic activity may be responsible of the symptomatological worsening in delusional depressives observed after TSD.

Adult↗
PubMedDate not supplied

Failure of ursodeoxycholic acid to dissolve radiolucent gallstones in patients with cystic fibrosis.

Ursodeoxycholic acid has been used widely to dissolve cholesterol gallstones and more recently was shown to improve clinical symptoms and biochemical indices in different chronic liver diseases, including that associated with cystic fibrosis. We treated 10 cystic fibrosis patients (5 males, 5 females, age range 2-22 years) with pancreatic insufficiency and normal liver function with ursodeoxycholic acid 15-20 mg/kg/day. Seven patients had radiolucent gallstones (in 3 cases associated with biliary sludge) and 3 had sludge; all were asymptomatic. Before treatment, the gallbladder was well opacified in oral cholecystogram. The gallbladder was scanned by ultrasound in similar conditions and by the same operator before administration of ursodeoxycholic acid and after a median period of treatment of 16 months (range 11-32 months). During treatment, all patients remained asymptomatic and the relative proportion of ursodeoxycholic acid in duodenal bile increased from 4.7 +/- 3.2% at baseline to 34.7 +/- 8.6%. Complete or partial dissolution of gallstones was never observed and the maximum diameter of stones increased from a mean of 6.1 +/- 3.4 to 8.0 +/- 5.3 mm; in one case the development of biliary sludge occurred during bile acid therapy. Sludge disappeared in 1 of the 6 patients who initially had it, while in 2 cases its volume increased. We conclude that ursodeoxycholic acid is not effective in most CF patients with gallstones, probably because cholesterol is not the main component of stone or sludge.

Adolescent↗
PubMedDate not supplied

Evaluation of reactive oxygen metabolites in frozen serum samples. Effect of storage and repeated thawing.

Measuring the free radical activity in serum samples from prospective studies is the best way to investigate the association between oxidative stress and human diseases. Prospective studies require the analysis of serum samples that have often been stored for a long time. Our study was designed to determine the effect of storage at -30 degrees C and -80 degrees C for two years on free radical activity. We analyzed the free radical activity by measuring circulating hydroperoxides in a pool of sera at baseline and after one day, one week, one month and 25 months of storage, using a photometric method (d-ROMs test). Measurements were performed in aliquots thawed only once at each time point and in aliquots frozen and thawed repeatedly over the study period. After two years we observed a small but statistically significant 4% decrease in the hydroperoxide concentration, which was substantially unaffected by storage temperatures and repeated freeze-thaw cycles. We also carried out the d-ROMs test in sera from ten apparently healthy volunteers at 2, 8, 24, and 48 hours after collection and storage at 4 degrees C and did not observe any significant variation. In conclusion, the d-ROMs test is a simple method suitable to evaluate the free radical activity in frozen serum samples after long-term storage.

Adult↗
PubMedDate not supplied

Plant-based diet, serum fatty acid profile, and free radicals in postmenopausal women: the diet and androgens (DIANA) randomized trial.

High calorie and fat consumption and the production of free radicals are two major mechanistic pathways between diet and disease. In this study we evaluated the effect of a plant-based diet poor in animal fat and rich in (n-3) fatty acids on fatty acids of serum phospholipids and on the production of reactive oxygen metabolites (ROMs). One hundred and four healthy female postmenopausal volunteers were recruited and randomized to a dietary intervention or a control group. Dietary intervention included a program of food education and biweekly common meals for 18 weeks. When the intervention and control groups were compared, it was seen that dietary intervention resulted in a significant reduction of saturated fatty acids (-1.5%) and a significant increase in (n-3) fatty acids (+20.6%), in particular docosahexaenoic acid (+24.8%). We observed that arachidonic acid decreased (-7.7%), while (n-6) fatty acids did not, and the (n-3)/(n-6) polyunsaturated ratio increased significantly (+24.1%). As expected, ROMs decreased significantly in the intervention group (-6%). The results indicated that a plant-based diet can improve the serum fatty acid profile and decrease ROMs production. These results suggest that a plant-based diet may reduce the body's exposure to oxidative stress.

Aged↗
PubMedDate not supplied

Effect of fluorinated groups on photooxidative stability of polymeric protectives applied on marble.

Some new protective copolymers and a commercial one have been tested on Candoglia marble, a very low porosity stone. Two of the polymers contained a partially fluorinated methacrylic monomer, 2,2,2 trifluoro ethyl methacrylate (TFEMA), in combination with either an acrylic, methyl acrylate (MA) or a vinyl ether, n-butyl vinyl ether (n-BVE) unit. Two copolymers, ethyl methacrylate/n-butyl vinyl ether and ethyl methacrylate (EMA)/methyl acrylate (Paraloid B72), were non-fluorinated and similar in compositions and molar ratio. The aim of the work is to test the copolymers and compare the performances of fluorinated new polymers with the non fluorinated one and with the largely used commercial product. The results obtained demonstrate that the introduction, even in limited amounts, of fluorine atoms in the side ester groups of methacrylic type polymers really improves their protective effect and the durability of the stone treatments. The best results were obtained with the copolymer TFEM/MA which is the fluorinated homologous of Paraloid B72.

Acrylates↗
PubMedDate not supplied

Atypical coloration of plaster in renaissance frescoes.

The Baptistery of Castiglione Olona (Varese, Italy), frescoed by Masolino da Panicale at the beginning of the 14th Century, is currently under restoration. On this occasion its state of preservation was investigated, in order to plan a correct intervention. During the sampling, an interesting phenomenon was pointed out, i.e. a wide rose coloration on the plasters of the interior northern and western walls. In order to clarify the nature of the alteration, a sampling was undertaken both for a chemical-mineralogical characterization of plasters (XRD, SEM-EDX, FTIR) and to detect the presence of biodeteriogens.

Construction Materials↗
PubMedDate not supplied

Evaluation of barium hydroxide treatment efficacy on a dolomitic marble.

The Arch of Peace, by Luigi Cagnola, is one of the most famous neoclassical monuments in Milan. It has been subjected to conservative intervention in 1998. In the present paper the efficacy of the consolidation by means of barium hydroxide has been evaluated. The stone material showed severe degradation phenomena as: erosion, pulverisation, exfoliation. The analytical data acquired through X-ray diffraction (XRD), infrared spectrophotometry (FTIR) and scanning electron microscopy (SEM-EDX), allowed to compare the conditions of stone before and after the treatment with barium hydroxide. The presence of barium has been put in evidence mainly on the surface as barium sulphate, whereas barium is only sporadically present within the thickness of the decayed material. The treatment was judged not satisfying and its inefficacy is, most probably, due to a not suitable cleaning procedure carried out before the consolidation.

Barium Compounds↗
PubMedDate not supplied

The steatocrit: a simple method for monitoring fat malabsorption in patients with cystic fibrosis.

Steatocrit was determined through microcentrifugation of fecal homogenate from 110 pediatric controls and 107 patients with cystic fibrosis (CF). For 74 CF patients, steatocrit was determined in the same fecal material collected to determine a fat balance. In controls, steatocrit value was 0.7 +/- 1.0%, which was significantly lower than values found in CF patients with a coefficient of fat excretion less than 10% of intake (1.7 +/- 1.2%). Significantly increased values were found in CF patients with a coefficient of fat excretion ranging between 10 and 25% of intake (4.7 +/- 1.7%) and in those whose coefficient of fat excretion was greater than 25% of intake (11.3 +/- 4.3%). In the 74 CF patients, steatocrit was directly correlated to the coefficient of fat excretion (r = 0.93; P less than 0.001). We performed steatocrit several times in the course of the 1st year of life in 33 infants with CF diagnosed by means of CF screening. Values obtained at the time of diagnosis, before starting enzymatic therapy, were relatively high; they showed a progressive decrease when, using steatocrit as a guide, the dose of pancreatic enzymes had been increased. The normalization of steatocrit values was accompanied by a better growth rate in the majority of these infants, confirming the importance of an optimal early correction of pancreatic insufficiency. We propose that this simple semiquantitative test can be usefully performed for the frequent monitoring of fat absorption and for checking the response to enzymatic therapy in patients with CF.

Adolescent↗
PubMedDate not supplied

[Congenital dilatation of the choledocus. Diagnostic considerations and therapeutic indications].

From 1964 to 1979, 7 children affected by congenital choledocal cyst were operated on. A cysto-duodenostomy was performed in all cases but one, in whom an excision of the cyst was directly carried on. In the light of the this experience Authors conclude that direct excision is preferable rather than a cysto-duodenostomy and furthermore possible to be arrived at basically by means of ultrasound. This latter one is considered so far the best way to reach a pre-operative conceptualization of the pathology.

Common Bile Duct Diseases↗
PubMedDate not supplied

Irritable bowel syndrome in children: an Italian multicentre study. Collaborating Centres.

A multicentre study was carried out on 285 children suffering from irritable bowel syndrome (IBS). Patients were divided according to clinical symptoms and age: Toddler's diarrhoea (TD) under 3 years of age and recurrent abdominal pain (RAP) over 3 years of age characteristics in children with TD and RAP were compared with those found in 114 subjects suffering from various gastrointestinal diseases (GIC) and in 192 normal children. This analysis allowed a complete profile of children with IBS in Italy to be obtained. The TD group, and to a lesser extent the RAP group, differ from the GIC and healthy controls (HC) on the basis of telephone calls to the doctor, physician visits, inappropriate dietary restrictions, multiple medications and multiple non-GI complaints. For children under 3, a history of food intolerance and the presence of mucus and undigested food in the feces are the variables that discriminate patients with IBS from those with GIC; for children over 3, colics in the first 3 months of life, a history of food intolerance, loose feces with abdominal pain, pain relieved by evacuation and undigested vegetables in the feces most discriminate the two groups. Finally, we tried to compute a diagnostic score to discriminate IBS children from GIC: this proved to be sensitive to IBS but not specific enough to be of clinical utility.

Abdominal Pain↗
PubMedDate not supplied

Time course and concentration dependence of the incorporation of deuterated/tritiated arachidonic acid and derived fatty acids in THP-1 cell lipids.

We have supplemented THP-1 cells, a human monocytic leukemia cell line, with arachidonic acid (AA), containing [3H8] AA, 1-25 microM, for up to 24 hours, and explored the time and concentration dependent patterns of incorporation in cell lipid classes and subclasses. Twenty-five microM AA consisted of deuterated AA ([2H8] AA), containing also [3H8] AA. Phospholipids (PL) were separated by HPLC with UV and radiodetection, and the fatty acids (FA) methyl esters were analyzed by GC. [2H8] AA pentafluorobenzyl-esters from individual lipid classes were obtained and analyzed by GC-MS. Incorporation of AA in cell lipids increased linearly with increasing concentrations, whereas 22:4 and 22:5 accumulated only at 25 microM AA. Up to 10 microM AA, more than 95% of the FA was incorporated in PL, whereas at 25 microM AA a significant proportion of the exogenous FA was incorporated in triglycerides (TG) and in diacyl phosphatidylcholine (PC). The time-course of AA incorporation showed that the peak was at 3 hours, with minimal incorporation in TG, in the presence of 5 microM, whereas the peak occurred at 6 hours, with about 50 percent incorporation in TG, with 25 microM. The data indicate that the range of AA concentrations and the time course of the incorporation of this FA in cell structural lipids are critical.

Arachidonic Acid↗