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S Cosentino

Publications and source records attributed to S Cosentino.

At least 19 recordsLinked to original sources
PubMed2004

Occurrence and characterization of yeasts isolated from artisanal Fiore Sardo cheese.

The occurrence of yeast microflora in artisanal Fiore Sardo cheese during ripening was studied. Mean yeast counts ranged from 2.64+/-1 log(10) cfu ml(-1) in milk to 0.65+/-1 log(10) cfu g(-1) in 9 months cheese, with the higher counts observed in 48-h-old cheese. Strains belonging to the prevalent species Debaryomyces hansenii, Kluyveromyces lactis, Geotrichum candidum, Candida zeylanoides and Candida lambica were selected for technological and genotypic characterization. All D. hansenii strains fermented glucose and assimilated lactate, a high percentage assimilated citrate and only a few showed proteolytic and lipolytic activity. All K. lactis strains were able to both assimilate and ferment lactose, to assimilate lactate and to exhibit proteolytic activity on casein. G. candidum assimilated lactate and some strains showed proteolytic and lipolytic activity. C. zeylanoides showed lipolytic activity on tweens and the majority of strains assimilated citrate. C. lambica fermented glucose and assimilated lactate. Considering their diffusion and technological characteristics, an important role for K. lactis and G. candidum in the early stages of the ripening process and for D. hansenii after the first month of ripening can be suggested. RAPD-PCR analysis with M13 primer grouped the isolates in well-separated clusters with their type strains and confirmed the previous phenotypic identification. The high intraspecific homogeneity observed in tested strains could be explained by their isolation from a common substrate and from neighbouring geographical areas. This preliminary study allowed us to isolate autochthon yeast strains showing particular properties which can contribute to the production of typical cheese taste and flavour.

Animals↗
PubMed2002

Investigation of brain tumours with (99m)Tc-MIBI SPET.

The aim of this paper is to give the reader an updated overview of (99m)Tc-MIBI SPET applications in investigating brain tumours. Elements determining MIBI uptake at the level of the brain are first mentioned. (99m)Tc-MIBI SPET features in different malignant and benign brain lesions (low and high grade gliomas, glioblastoma multiforme, metastasis, lymphoma, meningioma, neuroma, radiation necrosis and other rarer brain lesions) are reviewed. The ability of 99mTc-MIBI SPET, alone or in combination with other radiotracers, in the differential diagnosis of brain lesions is discussed. We outline (99m)Tc-MIBI SPET value in determining brain tumours grading and in distinguishing tumour recurrence from radiation necrosis. Clinical applications of 99mTc-MIBI in the management of AIDS patients, where discrimination between lymphoma and several different lesions only on the basis of CT or MRI findings is often impossible, are reported. In addition the relationships among (99m)Tc-MIBI SPET, P-glycoprotein (MDR-1 gene product) expression in brain neoplasms and chemotherapy response are mentioned.

Brain Neoplasms↗
PubMed2001

Yeasts associated with Sardinian ewe's dairy products.

In the present work, the occurrence of yeasts in different types of typical Sardinian ewe's cheeses (32 samples of pecorino, 32 of caciotta, 40 of feta, 56 of ricotta) was determined. For the strains isolated the following properties were studied: proteolytic and lipolytic activities, the ability to grow at different temperatures, different concentrations of salt, and to assimilate and/or ferment compounds like lactate, citrate, lactose, glucose, galactose, lactic acid. Of 160 samples analysed, 76.2% yielded growth of yeasts. Yeast counts showed a certain variability among the samples. The highest levels were observed in caciotta and feta cheeses. A total of 281 strains belonging to 16 genera and 25 species were identified. In general, Debaryomyces hansenii was the dominant species, representing 28.8% of the total isolates. Other frequently appearing species were Geotrichum candidum, Kluyveromyces lactis and K. marxianus. Other genera encountered were Pichia, Candida, Dekkera, Yarrowia and Rhodotorula. With regard to the biochemical and technological properties of the yeasts, only K. lactis, K. marxianus and Dek. anomala assimilated and fermented lactose, whereas the majority of the species assimilated lactic acid. The assimilation of citrate was a characteristic of D. hansenii, R. rubra and Y. lipolytica. On the whole, the yeasts were weakly proteolytic while lipolytic activity was present in several species. A high percentage of strains showed a certain tolerance to low temperatures while only some strains of D. hansenii and K. lactis were able to grow at a 10% NaCl concentration.

Animals↗
PubMed2001

Yeast populations in Sardinian feta cheese.

In this study, the yeast populations in feta cheese from two different Sardinian dairies were examined. Samples of good quality feta (32) and samples of feta with a slimy surface defect (10) were examined from Dairy A. Similar, samples of good quality feta (23), feta with slimy surface defects (14) and samples with swelling defects (6) were examined from Dairy B. Kluyveromyces lactis was the dominating species in feta from Dairy A (95.2% of samples) followed by Debaryomyces hansenii (76.2%), Dekkera anomala (28.6%) and Dek. bruxellensis (19%). D. hansenii was dominant in samples from Dairy B (93%), followed by K. lactis (23.3%), Geotrichum candidum (23.3%) and Dek. anomala (18.6%). No significant difference was observed between the occurrence of yeast species in feta of good quality and in feta with slimy surface defects, thus confirming that slimy production is not associated with yeast contaminations. The swelling of samples observed in Dairy B seems to be caused by Dek. anomala. In fact, this strong fermenting species was present in all swelled samples in numbers exceeding 10(6) CFU g(-1), while it was isolated in very low concentration in only 5.4% of good samples.

Cheese↗
PubMed2001

[Microbial environmental surveillance in a bone marrow transplant unit].

The aim of this study was to evaluate, after several years of application, in a bone marrow transplant (BMT) center of a Cagliari Hospital, the effectiveness of the disinfection protocol in minimizing the risk of environmentally transmitted infections. Microbial contamination of the air was evaluated every two months during normal activity using an SAS sampler. The contamination of surfaces was determined weekly, 2hrs after sanitation, using disposable surface contact plates. The results of environmental monitoring generally showed low values of microbial contamination of air and surfaces. Only two service rooms and two patient's rooms without own bathroom showed levels of microbial contamination slightly exceeding, in a few samplings, the values considered acceptable for environments at high risk of infections. From a qualitative point of view, the microrganisms isolated generally belonged to environmental species. In conclusion our study confirms the importance of microbial monitoring in the control and prevention of outbreaks of infections in BMT Units. This approach allows significant reduction in the level of contamination not only by improving cleaning procedures, but also by motivating the cleaning staff trough making them aware of their responsibilities.

Air Microbiology↗
PubMed2001

[Microbial circulation and control in two Intensive Care Units].

A microbiological survey was carried out in two medical Intensive Care Units from January to June 2000. The patients, staff (hands and upper respiratory tract) and environment were monitored. The results obtained in both Care Units give cause for concern. They showed particularly high cultural positivities in bronchoaspirates collected from artificially ventilated patients, a high percentage of positive environmental samples, and frequently contaminated hands in hospital staff, conditions which may facilitate microbial circulation in the medical Intensive Care Units. It would therefore seem necessary to promptly apply specific preventive measures for both the environment and patients.

Bacteria↗
PubMed2000

Exacting assessments: do older adults fatigue more quickly?

To determine whether neuropsychological testing is fatiguing, and whether it is more fatiguing to older than younger adults, 351 healthy, community living adults, between 18 and 91 years of age, completed a 3 to 4 hour battery of tests focusing on sensation, perception, attention, memory and knowledge. The battery included 3 critical tests: one for assessing the speed of making simple reactions and two for assessing the speed of making decisions. For half of the participants, the critical tests were administered only once, at the end of the session; for the remaining participants, the critical tests were given at the beginning and end of the session. The results show no evidence of fatigue effects with participants from any age group. In view of the type and variety of instruments in our battery, we believe our results will generalize to a wide range of testing situations. The participants in our study were healthy adult volunteers, however, and thus we recommend caution in generalizing the results to clinical populations.

Adult↗
PubMed1999

In-vitro antimicrobial activity and chemical composition of Sardinian Thymus essential oils.

Essential oils and their components are becoming increasingly popular as naturally occurring antimicrobial agents. In this work the chemical composition and the antimicrobial properties of Thymus essential oils and of their main components were determined. Three essential oils obtained from different species of Thymus growing wild in Sardinia and a commercial sample of Thymus capitatus oil were analysed. The essential oil components were identified by GC/MS analysis. The antimicrobial activity of the oils and components was determined against a panel of standard reference strains and multiple strains of food-derived spoilage and pathogenic bacteria, using a broth microdilution method. The GC/MS analysis showed that the major constituents of the oils were monoterpene hydrocarbons and phenolic monoterpenes, but the concentration of these compounds varied greatly among the oils examined. The results of the antimicrobial assay showed that essential oils extracted from Sardinian Thymus species have an antimicrobial activity comparable to the one observed in other thyme oils. It seems also confirmed that the antimicrobial properties of thyme essential oils are mainly related to their high phenolic content. Among the single compounds tested carvacrol and thymol turned out to be the most efficient against both reference strains and food-derived bacteria. The results of this study confirmed the possibility of using thyme essential oils or some of their components in food systems to prevent the growth of foodborne bacteria and extend the shelf-life of processed foods.

Anti-Bacterial Agents↗
PubMed1998

Influence of hepatitis G virus coinfection on the clinical course of chronic hepatitis C.

Hepatitis G virus (HGV) is a parenterally transmitted virus, frequently associated with hepatitis C virus infection. Hepatitis G virus RNA was detected by reverse transcription-polymerase chain reaction in the serum of 40 patients with chronic hepatitis C. Nine (22.5%) patients had evidence of hepatitis G virus viraemia. No significant epidemiological or virological differences could be demonstrated between subjects infected with both hepatitis G virus and hepatitis C virus and subjects infected with hepatitis C virus alone. Aminotransferase values were comparable between the two groups, whereas higher levels of cholestatic enzymes (P< 0.001) were reported in the hepatitis G virus/hepatitis C virus-positive patients. A liver biopsy was performed on all 40 patients no later than 6 months before recruitment. The mean histological activity index did not differ between hepatitis G virus-positive and hepatitis G virus-negative patients, whereas specific histological features such as macrovesicular steatosis, portal granulomas, and bile duct damage were more commonly observed among the coinfected patients. The results indicate that coinfection with hepatitis G virus probably does not have a significant effect on hepatitis C virus-induced hepatic damage.

Adult↗
PubMed1997

Incidence and biochemical characteristics of Bacillus flora in Sardinian dairy products.

This study was planned to assess the frequency and level of Bacillus spp. contamination in Sardinian dairy products and to evaluate some food-spoilage-related characteristics of the strains isolated. Of the 378 dairy products tested, 265 (70%) were found to contain Bacillus spp. The overall level of contamination ranged from less than 10 cfu per ml or gram up to a maximum of 1200 cfu. A total of 483 strains, belonging to 14 species, have been isolated from the 265 positive samples. The most frequently isolated psychotropic species were B. cereus (18.6% of total isolates), B. coagulans and B. mycoides. B. subtilis, B. licheniformis and B. pumilis were the most common mesophilic strains and B. stearotermophilus was the dominant thermophilic species. Most strains showed strong enzymatic activity, as indicated by the high percentage of isolates capable of hydrolysing casein, gelatin, starch and liquids. As regards possible health hazards. 72% of the B. cereus strains tested showed evidence of toxin production using a reversed passive latex agglutination assay.

Bacillus↗
PubMed1997

[The physician in Italy between late antiquity to early middle age. Social typologies and forms of cultural representation].

The imperial legislation of Theodosian and Justinian codes pays attention above all to the archiatri sacri palatii and to the Roman archiatri. Her lexicon is ambiguous and it is difficult to understand by the legislation what the term archiater really means in Late Antiquity. Prosopographical analysis allows to outline various social figures of medical doctors: archiatri of the sacred palace, iatrosophistai, civic physicians, statal physicians, military physicians, ecclesiastical physicians. By some epitaphs of the 5th century emerges that physicians were conscious of the social role of medicine, and they were proud of it. Medicine was thought in contemporary culture as ars honesta; this fact implies that, on the average, her practitioners were placed on the same level of craftsmen and tradesmen (i.e. viri honesti). In spite of the christian thought increased her attention on medical assistance of the poors, the physician's position lost his own visibility in our sources between the 5th to the 7th century. This fact is due to the change in thinking the concept of sickness: in christian world, sickness is not only a physical deficiency but becomes also a spiritual deficiency. Consequently the saint, and not the physician, becomes the symbolic figure whom people entrusts his own anxiety of salvation.

History, Ancient↗
PubMed1996

Peroxidase deficiency of nickel-transformed hamster cells correlates with their increased resistance to cytotoxicity of peroxides.

Using a procedure aimed at isolation of genes that are inactivated during nickel-induced carcinogenesis in Chinese hamster cells, a homolog of genes encoding human and mouse heme containing peroxidases has been cloned. Northern blot analysis of normal cultured fibroblasts and two nickel-transformed cell lines confirmed that this gene was expressed in normal but not in transformed cells. Nickel-transformed cells also tested negative for peroxidase activity using a sensitive fluorescence assay. Cultured embryo cells or fibroblasts that express peroxidase activity and their nickel-transformed peroxidase-deficient counterparts were employed to investigate the role of peroxidase-catalyzed processes in cytotoxicity induced by tert-butyl hydroperoxide or cumene hydroperoxide. It has been found that peroxidase-deficient cells were significantly more resistant to cytotoxic effect of these compounds suggesting that cytotoxic effect of hydroperoxides may be mediated in part by free radicals generated in the course of peroxidase-catalyzed reactions.

Animals↗
PubMed1995

Endoscopic treatment of postoperative colonic strictures using an achalasia dilator: short-term and long-term results.

BACKGROUND AND STUDY AIMS: Endoscopic dilation has proven to be a valid therapeutic alternative to surgery for treating postoperative anastomotic colonic strictures. The authors here evaluate retrospectively the short and long-term clinical results obtained in such patients by pneumatic dilation. PATIENTS AND METHODS: From March 1986 to December 1993, 18 patients who had undergone surgery for colorectal cancer were treated for a postoperative symptomatic stricture. Four patients had undergone a left hemicolectomy and 14 an anterior resection. The strictures had a diameter of less than 2 mm, and a length ranging from 5 to 29 mm. The dilations were performed using a 30-40 mm pneumatic dilator for achalasia. The clinical results were classified in relation to the abdominal symptomatology reported by the patients, and were evaluated in the short term (one week) and long term (mean follow-up: 39 months). RESULTS: Seventeen of the 18 patients underwent a total of 45 dilating sessions; one patient was excluded because a recurrence was diagnosed at the suture line. Five patients had a single dilating session; eight patients had two sessions, and four patients had a mean of 4.5 sessions. Two complications were observed: a punctiform bowel perforation and one transient mucosal bleeding. Immediate symptomatic relief was achieved in all cases, and good long-term clinical results were achieved in 16 patients (94.1%). CONCLUSIONS: Endoscopic dilation with an achalasia balloon has proved to be safe and simple to perform, and allowed us to obtain good short-term and long-term clinical results. This type of dilation may be considered the first-line therapeutic approach for symptomatic benign colonic anastomotic strictures.

Adult↗
PubMed1995

[Not Available].

We report a case of oro-pharyngeal and oesophageal ulcerative disease in a AIDS patient. The patient complained of severe oral pain and dysphagia. Systemic manifestations as fever and fatigue were also present. Repeated microbiological exams were negative and therapy with either antibiotics or antiviral agents or corticosteroids or colchicine was unsuccessful. Thus, we started thalidomide: 200 mg/day X 21 days, followed by 100 mg/day X 25 days. A dramatic reduction of symptoms was observed within 15 days from the onset of treatment. The healing of ulcers was evident already one month after the start of therapy. No relevant side effects were reported. Among those patients with AIDS at low risk of side effects, thalidomide may represent a successful therapeutic presidium for severe ulcerative disease of the gastrointestinal tract.

English Abstract↗
PubMed1995

Anti-HCMV serologic response in patients with acute viral hepatitis.

The authors point out a high serological incidence of HCMV infection in the course of HCV hepatitis compared to a low incidence detected in HBV and HAV hepatitis. Three immunoglobulin classes (IgG, IgM, and IgA) specific to HCMV were investigated. Antibody titers of each immunoglobulin class are reported for all the cases of HCMV infection.

Acute Disease↗
PubMed1994

Molecular mechanisms of nickel carcinogenesis.

Nickel treatment of intact cultured cells oxidized dichlorofluorescin to a fluorescent product indicating that nickel elevated the level of oxidants in cells. Nickel also caused an increase in crosslinking of amino acids to DNA and these complexes did not appear to involve the direct participation of Ni2+. Histidine, cysteine and tyrosine were prominent among the amino acids crosslinked to DNA. Nickel selectively damaged heterochromatin and this resulted in deletions of heterochromatic regions during nickel carcinogenesis. Thrombospondin was one of the genes expressed in normal cells that was not expressed in nickel-transformed cells. Other aspects of the molecular mechanism of nickel carcinogenesis are discussed.

Amino Acids↗
PubMed1994

Loss of thrombospondin transcriptional activity in nickel-transformed cells.

mRNA from normal Chinese hamster embryo (CHE) cells was transcribed to cDNA and subtracted with an excess of mRNA from Chinese hamster embryo cells transformed by nickel compounds. Here we report the recovery of a sequence found to be highly homologous to the mouse thrombospondin 1 gene that was obtained by this subtraction procedure. Since thrombospondin is antiangiogenic, cancer cells expressing high levels of thrombospondin cannot grow in vivo because capillaries will not proliferate to cells secreting thrombospondin. To examine expression of thrombospondin, normal CHE cells were stained with monoclonal antibodies to human thrombospondin. The protein was present abundantly in the cytoplasm of normal cells but at greatly reduced levels in Ni-transformed cells. Analysis of mRNA by Northern (RNA) blot revealed transcripts in normal cells but little thrombospondin mRNA in Ni-transformed cells. Loss of thrombospondin mRNA expression was related to Ni treatment rather than transformation, since Ni-resistant cells also exhibited fewer thrombospondin transcripts than did wild-type cells. Digestion of genomic DNA with various combinations of restriction enzymes revealed thrombospondin gene patterns that were identical in both cell types, suggesting that there were no major deletions or rearrangements of the gene in the nickel-transformed cells. The inactivation of the thrombospondin gene was further investigated by analyzing the promoter activity of this gene linked to a chloramphenicol acetyltransferase (CAT) reporter plasmid that was transfected into normal and Ni-transformed cells. The CAT activity in normal cells was significantly higher than in Ni-transformed cells, suggesting that the promoter region of thrombospondin was less efficiently transcribed in Ni-transformed cells. We studied the consequences of enhanced expression of the retinoblastoma (Rb) gene, a known tumor suppressor gene, on CAT transcription driven by the human thrombospondin promoter. Cotransfection of an expression vector containing the mouse Rb gene greatly enhanced the transcription from the thrombospondin promoter such that the expression was higher in normal cells than in transformed cells.

Amino Acid Sequence↗