Impaired taste sensation in type 2 diabetic patients without chronic complications: a case-control study.

PURPOSE: Few and contradictory data suggest changes in taste perception in type 2 diabetes (T2DM), potentially altering food choices. We, therefore, analyzed taste recognition thresholds in T2DM patients with good metabolic control and free of conditions potentially impacting on taste, compared with age-, body mass index-, and sex-matched normoglycemic controls. METHODS: An ascending-concentration method was used, employing sucrose (sweet), sodium chloride (salty), citric acid (sour), and quinine hydrochloride (bitter), diluted in increasing concentration solutions. The recognition threshold was the lowest concentration of correct taste identification. RESULTS: The recognition thresholds for the four tastes were higher in T2DM patients. In a multiple regression model, T2DM [ß = 0.95; 95% CI 0.32-1.58; p = 0.004 (salty); ß = 0.61; 0.19-1.03; p = 0.006 (sweet); ß = 0.78; 0.15-1.40; p = 0.016 (sour); ß = 0.74; 0.22-1.25; p = 0.006 (bitter)] and waist circumference [ß = 0.05; 0.01-0.08; p = 0.012 (salty); ß = 0.03; 0.01-0.05; p = 0.020 (sweet); ß = 0.04; 0.01-0.08; p = 0.020 (sour); ß = 0.04; 0.01-0.07; p = 0.007 (bitter)] were associated with the recognition thresholds. Age was associated with salty (ß = 0.06; 0.01-0.12; p = 0.027) and BMI with sweet thresholds (ß = 0.06; 0.01-0.11; p = 0.019). CONCLUSIONS: Taste recognition thresholds were higher in uncomplicated T2DM, and central obesity was significantly associated with this impairment. Hypogeusia may be an early sign of diabetic neuropathy and be implicated in the poor compliance of these patients to dietary recommendations.

Studies on the mechanism of action of pederine.

Pederine, a drug extracted from the coleopter Paederus fuscipes, inhibits the growth of in vitro cultured cell lines at concentrations of the order of 1.5 nanogram/ml. Cytological examination shows a generalized cytotoxic effect. Analysis of macromolecular syntheses by the use of radioactive precursors shows that pederine causes an almost immediate block of protein and DNA synthesis, without affecting RNA synthesis. The effects on the synthesis of the two types of macromolecules remain nearly simultaneous even at the lowest active concentrations of pederine. Studies with cell-free systems show that the drug inhibits protein synthesis, whereas it is ineffective on the DNA-polymerizing activity. It seems, therefore, that the drug acts primarily on the amino acid-polymerizing system, and that the effect on DNA is secondary. This idea is strengthened by the observation that puromycin, a specific inhibitor of protein synthesis, also affects promptly DNA synthesis of in vitro cultured cells. Other authors have shown the same phenomenon with a number of inhibitors of protein synthesis; the properties of pederine support, therefore, the view that continuous protein synthesis is necessary for the maintenance of DNA replication in higher organisms.

Overexpression of N-ras oncogene and epidermal growth factor receptor gene in human glioblastomas.

Five human glioblastoma cell lines were analyzed for oncogene activation with a panel of probes. Abnormal expression of the epidermal growth factor receptor (EGFr) gene was detected in four of five lines; N-ras oncogene overexpression was found in all five cell lines. These results were subsequently confirmed with fresh brain tumor and nonneoplastic brain tissue biopsy samples; increased expression of the N-ras proto-oncogene was observed in five of five glioblastomas, all of which also showed EGFr gene overexpression, but not in well-differentiated gliomas or in nonneoplastic brain tissue specimens. No significant differences in Ha-ras and Ki-ras expression were observed. Preliminary histochemical observations showed that intracellular levels of transforming growth factor alpha, a putative biochemical link between these two oncogenes, were significantly higher in glioblastoma cells than in controls.

Preoperative oral immunonutrition versus standard preoperative oral diet in well nourished patients undergoing pancreaticoduodenectomy.

BACKGROUND: Pancreaticoduodenectomy is still associated to high morbility, especially due to pancreatic surgery related and infectious complications: many risk factors have already been advocated. Aim of this study is to evaluate the role of preoperative oral immunonutrition in well nourished patients scheduled for pancreaticoduodenectomy. METHODS: From February 2014 to June 2015, 54 well nourished patients undergoing pancreaticoduodenectomy were enrolled for 5 days preoperative oral immunonutrition. A series of consecutive patients submitted to the same intervention in the same department, with preoperative standard oral diet, was matched 1:1. For analysis demographic, pathological and surgical variables were considered. Mortality rate, overall postoperative morbility, pancreatic fistula, post pancreatectomy haemorrhage, delayed gastric emptying, infectious complications and length of hospital stay were described for each groups. Chi squared test, Fisher's Exact test and Student's T test were used for comparison. Differences were considered statistically significant at p < 0.05. Statistics was performed using a freeware Microsoft Excel (®) based program and SPSS v 10.00. RESULTS: No statistical differences in term of mortality (2.1% in each groups) and overall morbility rate (41.6% vs 47.9%) occurred between the groups as well as for pancreatic surgery related complications. Conversely, statistical differences were found for infectious complications (22.9% vs 43.7%, p = 0.034) and length of hospital stay (18.3 ± 6.8 days vs 21.7 ± 8.3, p = 0.035) in immunonutrition group. CONCLUSION: Preoperative oral immunonutrition is effective for well nourished patients scheduled for pancreaticoduodenectomy; it helps to reduce the risk of postoperative infectious complications and length of hospital stays.

Blood pressure and sodium intake from snacks in adolescents.

BACKGROUND/OBJECTIVES: The relationship between sodium intake and arterial blood pressure (BP) values in adolescence is still controversial. The intake of high-sodium processed foods as snacks has gone up worldwide. The purpose of the present cross-sectional study was to analyze the association between BP values and sodium intake from snacks. SUBJECTS/METHODS: The mean weekly consumption of snacks was evaluated in 1200 randomly selected adolescents aged 11-13 years by a food-frequency questionnaire; their anthropometric and BP values were measured by trained researchers. A dietary 24-h food-recall questionnaire was randomly given to 400 of the 1200 adolescents. RESULTS: Mean sodium intake from snacks was 1.4 g/day. Systolic and diastolic BP (SBP and DBP, respectively) significantly increased from the lower to the higher tertile of sodium from snacks and with increasing frequency of salty snacks consumption. In a multiple logistic regression model, both being in the highest SBP quartile and in the highest DBP quartile were significantly associated with the intake of sodium from snacks (odds ratio (OR)=1.48; 95% confidence interval (CI) 1.14-1.91 and OR=2.17; 95% CI 1.68-2.79, respectively), the consumption of >2/day salty snacks (OR=1.86; 95% CI 1.32-2.63 and OR=2.38; 95% CI 1.69-3.37, respectively) and body mass index (OR=1.26; 95% CI 1.22-1.31 and OR=1.14; 95% CI 1.10-1.18, respectively) but not with age, sex or exercise levels. In the 400 individuals, the average total sodium intake was 3.1 g/day and was significantly higher in individuals belonging to the highest quartile of SBP and DBP. CONCLUSIONS: Sodium intake from snacks was almost half of the average daily sodium consumption and was significantly associated with BP values in adolescents.

Gene targeting to the centromeric DNA of a human minichromosome.

A human supernumerary minichromosome (MC), previously identified as a derivative of chromosome 9, has been introduced into Chinese hamster ovary (CHO) cells by means of cell fusion. A hybrid clone containing the MC as the only free human chromosome was isolated. A selectable marker gene (neo) inserted into a yeast artificial chromosome (YAC) has been successfully targeted to the MC centromeric DNA via co-transfection with chromosome-9-specific alpha satellite DNA. In situ hybridization and Southern blotting experiments demonstrated that the intact neo gene was integrated into the MC centromeric DNA. Studies on the clonal distribution and on the stability of the MC either in the presence or in the absence of the selective agent have been carried out. The MC is susceptible to further manipulations and may thus represent a model for the construction of a large-capacity vector for somatic gene therapy.

Molecular cloning of DNA from a sorted human minichromosome.

A human supernumerary minichromosome (MC), found in a newborn baby and sorted on a fluorescence-activated cell sorter (FACS-440) has been previously described [Ferretti et al., Cytotechnology 1 (1987) 7-12]. We report here on the construction of a library of EcoRI fragments in the phage lambda gtWES.lambda B', starting from 7.5 ng of MC DNA, and describe the isolation of single-copy DNA clones from the library in a two-step procedure. We employed in situ hybridization to unambiguously select the clones specific for the MC, and used three of these clones to demonstrate that it originated from chromosome 9.

Variation of minisatellites in chemically induced mutagenesis and in gene amplification.

A mutation assay in cultured mammalian cells was developed based on direct analysis of minisatellite DNA. Chinese hamster cells (V79) were mutagenized with nitrosoguanidine and independent colonies were isolated and expanded. DNA fingerprints were then obtained after digestion with HinfI or HaeIII and hybridization with 33.15 and 33.6 probes (Jeffreys et al., 1985). 12 colonies from untreated cells were also analyzed. Digestion with HaeIII and hybridization with 33.15 probe detected the highest frequency of induced variants. The results suggest that minisatellite sequences are hypermutable sites that can be used to monitor the mutagenic effect of chemical agents. We have also analyzed the DNA fingerprints of 17 independent Chinese hamster (CHO) cell lines carrying amplification of the CAD gene. The DNA fingerprint analysis showed a variation in minisatellite regions in 3 lines while no variation was observed in independent colonies from the CHO parental cell line. The results suggest that these sequences may be hot spots for recombination during gene amplification.

Griseofulvin.

Griseofulvin (GF) is a mycotoxin produced by various species of Penicillium including P. griseofulvum Dierckx, P. janczewski (P. nigricans) and P. patulum. It is active against dermatophytic fungi of different species in the genera Microsporum, Trychophyton and Epidermophyton. Because of its capacity to concentrate in the keratinous layer of the epidermis and its relatively low toxicity in man, it has been extensively used in the therapy of dermatophytoses by oral administration. The biological activity of GF towards fungi is manifested as nuclear and mitotic abnormalities followed by distortions in the hyphal morphology. Mitotic segregation is also induced in fungi by GF treatment. In higher eukaryotes the cytostatic action of GF is essentially due to a mitotic arrest at late metaphase/early anaphase. The cytological effects observable both in vivo and in vitro on different plant and animal cell systems, include C-mitoses, multipolar mitoses and multinuclearity. Prolonged GF treatment in experimental animals provokes biochemical changes consisting mainly of disturbances of porphyrin metabolism, variation in the microsomal cytochrome levels and formation of Mallory bodies. In mice these alterations are followed by the development of multiple hepatomas. Evidence of tumor induction by GF has been obtained in mice and rats, but not in hamsters. GF may also act either as a promoting or a co-carcinogenic agent, depending on the circumstances of its administration. It has been found to increase the frequency of cell transformation induced by polyoma virus, but not to induce cell transformation per se. Induction of sperm abnormalities has been observed in GF-treated mice. The embryotoxic and teratogenic action of GF has been demonstrated in pregnant rats exposed during organogenesis. Genetic effects of GF have been investigated by the following tests: Salmonella/microsome mutagenicity assay, point mutations in mammalian and plant cells, DNA damage and repair, SCE, chromosome aberrations, micronuclei, dominant lethals, aneuploidy in lower and higher eukaryotes. A positive response has been obtained in the assays on numerical chromosome changes in all the systems analyzed; limited or inconclusive evidence has been obtained for SCE and structural chromosome changes. Doubled or highly polyploid sets can be detected in all types of cells during or immediately after GF treatment. A marked increase in chromosome number variation is observed at various times after withdrawal of the drug, with prevailing hyperdiploid and reduced sets in animal cells and plant cells respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Aneuploidy assay on diethylstilbestrol by means of in situ hybridization of radioactive and biotinylated DNA probes on interphase nuclei.

Aneuploidy tests by means of in situ hybridization with chromosome-specific DNA probes on interphase nuclei have been carried out on human lymphocytes treated with diethylstilbestrol (DES). A DNA probe specific for chromosome Y (Y97), either radioactive or biotinylated, was used for the assays. Autoradiography or FITC-conjugated antibiotin antibodies were employed to visualize the hybridization sites. A significant increase of hyperdiploid nuclei was obtained with both procedures and a dose-related effect was revealed using the biotinylated probe. The results obtained, while giving further support to the evidence that DES is able to induce aneuploidy in cultured human cells, also indicate that the sensitivity of the assay can be improved by using biotinylated probes coupled with fluorescent antibodies.

Frequencies of sister-chromatid exchanges in relation to cell kinetics in lymphocyte cultures.

The frequency of sister-chromatid exchanges (SCE) was determined on second-division metaphases of lymphocytes stimulated by phytohaemagglutinin (PHA) during 9 days of culture. By using either a continuous or a pulsed bromodeoxyuridine (BUdR) treatment, cells were selected that had divided only twice, or at least twice, after different culture periods. No significant differences were observed in the SCE frequencies among the various samples. The incidence of SCE appears to be independent of the proliferation properties of cultured lymphocytes, such as length of cell cycle, fast or delayed response to PHA and number of divisions performed in vitro.

Double Y as an indicator in a test of mitotic nondisjunction in cultured human lymphocytes.

A cytological test for the detection of non-disjunction in human cultured lymphocytes has been developed. The Y chromosome was used as a marker, because this chromosome is easily identifiable in mitosis after staining with quinacrine dihydrochloride without karyotyping. Non-disjunction can be directly revealed by scoring mitoses with two Ys. The test was applied to agents known for their ability to induce numerical and/or structural changes in chromosomes, namely benomyl, colcemid, distamycin A, mitomycin C and X-rays. In treated lymphocytes, increased frequencies of YY mitoses were found, ranging from 2.5 X 10(-4) to 61.2 X 10(-4) (control value less than or equal to 1.1 X 10(-4). The results suggest that the detection of fluorescent Y chromosomes on metaphases is suitable for determining induced non-disjunction in human cultured cells.

Chromosomal aberrations induced in human cultured cells by liposome-encapsulated deoxyribonuclease I.

Experiments of incorporation of a nucleolytic enzyme into human cells cultured in vitro have been carried out with the aim of inducing structural chromosome variations. Human heteroploid cells, either as asynchronous populations or enriched in mitoses, and PHA-stimulated lymphocytes were used as recipients. We found that all these cells when exposed to pancreatic DNAase I encapsulated in liposomes, either of multilamellar (MLV) or of small unilamellar (SUV) type, show an incidence of chromosome damage higher than that induced by the enzyme free in the incubation buffer. Our results indicate that liposomes are suitable vehicles for the transfer of an exogenous nuclease into human cultured cells. The enzyme remains functionally active and interacts with nuclear DNA, giving rise to chromosome lesions.

Characterization of an X;X translocation by cytological analysis and in situ hybridization.

An X;X chromosomal translocation was ascertained by conventional cytogenetic analysis in a phenotypically normal woman with secondary amenorrhea. In situ hybridization was performed with previously mapped X-specific DNA sequences to study the rearrangement at the molecular level. The results allowed us to demonstrate that the subject is monosomic for the distal region of the short arm of the X and trisomic for the distal region of the long arm.

DNA repair in UV-irradiated heteroploid cells at different phases of the cell cycle.

The variation of DNA repair activity during the cell cycle was studied by analysing the UV-stimulated DNA synthesis in cells synchronized in mitosis. This activity was detected both by autoradiography and by directly measuring the incorporation of tritiated thymidine in cells irradiated and incubated in the presence of hydroxyurea. Cells in all phases were found to be able to perform repair. However the activity appeared to be considerably lower in mitotic cells than in cell in other phases. Increasing values of repair capacity were observed in G1 cells, in mixed G2, S and M cells and in asynchronous cells. The relationship between these findings and data on survival rates in the same synchronized cells is discussed.