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Biomedical subjects

G Piva

Publications and source records attributed to G Piva.

At least 19 recordsLinked to original sources
PubMed2006

Lipid microencapsulation allows slow release of organic acids and natural identical flavors along the swine intestine.

The purpose of the present work was to investigate the in vivo concentrations of sorbic acid and vanillin as markers of the fate of organic acids (OA) and natural identical flavors (NIF) from a microencapsulated mixture and from the same mixture non-microencapsulated, and the possible consequences on the intestinal microbial fermentation. Fifteen weaned pigs were selected from 3 dietary groups and were slaughtered at 29.5 +/- 0.27 kg of BW. Diets were (1) control; (2) control supplemented with a blend of OA and NIF microencapsulated with hydrogenated vegetable lipids (protected blend, PB); and (3) control supplemented with the same blend of OA and NIF mixed with the same protective matrix in powdered form but without the active ingredient coating (non-protected blend, NPB). Stomach, cranial jejunum, caudal jejunum, ileum, cecum, and colon were sampled to determine the concentrations of sorbic acid and vanillin contained in the blend and used as tracers. Sorbic acid and vanillin were not detectable in pigs fed the control, and their concentrations were not different in the stomach of PB and NPB treatments. Pigs fed PB showed a gradual decrease of the tracer concentrations along the intestinal tract, whereas pigs fed NPB showed a decline of tracer concentration in the cranial jejunum and onwards, compared with the stomach concentrations. Sorbic acid and vanillin concentrations along the intestinal tract were greater (P = 0.02) in pigs fed PB compared with pigs fed NPB. Pigs fed PB had lower (P = 0.03) coliforms in the caudal jejunum and the cecum than pigs fed the control or NPB. Pigs fed the control or PB had a greater (P = 0.03) lactic acid bacteria plate count in the cecum than pigs fed NPB, which showed a reduction (P = 0.02) of lactic acid concentrations and greater (P = 0.02) pH values in the caudal jejunum. The protective lipid matrix used for microencapsulation of the OA and NIF blend allowed slow-release of both active ingredients and prevented the immediate disappearance of such compounds upon exiting the stomach.

Ammonia↗
PubMed2005

Effect of Bt corn on broiler growth performance and fate of feed-derived DNA in the digestive tract.

The aim of the study was to evaluate the effect on broiler performance of transgenic Bacillus thuringiensis (Bt) corn containing the Cry1A(b) protein compared with the corresponding near isogenic corn and to analyze the degradation of the Cry1A(b) gene in the digestive tract. Ross male broilers (432) were fed for 42 consecutive days with diets containing Bt or isogenic corn. Diet, Bt corn, and the isogenic form of the Bt corn were analyzed for composition and aflatoxin B1, fumonisin B1, and deoxynivalenol contents. Broiler body weight and feed intake were recorded at regular intervals (d 0, 21, and 42). The presence of the Cry1A(b) gene and plant-specific genes Zein and Sh-2 in gut contents of crop, gizzard, jejunum, cecum, and samples of blood was determined in 10 animals per treatment at the end of the trial using a PCR technique. Chemical composition was not different between Bt and its isogenic form, whereas the fumonisin B1 content for Bt was lower than for isogenic corn (2,039 vs. 1,1034 ppb; P < 0.05). The results of the growth study showed no difference for average daily weight gain (129.4 vs. 126.0 g/d), feed intake (63.4 vs. 61.8 g/d), and feed conversion ratio (1.95 vs. 2.02) among the groups. No significant relationship was observed between mycotoxins content and growth performances. Feed-derived DNA is progressively degraded along the digestive tract. Detection frequency of short fragments of maize-specific high copy number Zein gene was high but significantly decreased in distal sectors. An 1,800-bp fragment of the Cry1A(b) gene, corresponding to the minimal functional unit, was detected only in crop and gizzard of birds fed Bt corn. Sh-2 showed the same detection frequency of Cry1A(b) and was also found in birds fed isogenic corn. Blood samples were positive with low frequency only for the Zein gene fragment. No significant difference in DNA detection was observed between birds fed Bt and isogenic corn, indicating that DNA derived from transgenic feed undergoes the same fate as isogenic feed.

Aflatoxin B1↗
PubMed2004

Occurrence of mycotoxins and ergosterol in maize harvested over 5 years in Northern Italy.

Maize samples collected from storage bins and feed mills in Northern Italy between 1995 and 1999 were surveyed for the occurrence of aflatoxin B1 (AFB1), zearalenone (ZEA), deoxynivalenol (DON) and fumonisin (FB1); further, ergosterol was analysed as a fungal growth marker. The incidence and mean content of AFB1 were generally low; nevertheless, a remarkable contamination was found in two samples (109 and 158 microg kg(-1)), while five others exceeded 20 microg kg(-1). DON and ZEA mean levels were significantly higher in 1996 (2716 and 453 microg kg(-1)) with respect to the other years, when mean contents ranged from 7 to 30% and from 3 to 17%, respectively, expressed in per cent of 1996 contents. FB1 was present in all samples and was by far the most remarkable mycotoxin in Northern Italian maize, with the exception of samples from 1996. The average level was 3064 microg kg(-1), 69.6% of samples resulted over 1000 microg kg(-1) and 16.9% over 5000 microg kg(-1). Significant correlations were found between ergosterol and the major mycotoxin(s) in each year (FB1 in 1995 and 1997-99; ZEA + DON in 1996). Consequently, ergosterol seems to be a good index of the toxicological quality of maize. Climatic conditions influenced the growth of different fungal species. In 1996, the first 20 days of October were extremely rainy; these weather conditions delayed the harvest until the first week of November and favoured the growth of DON and ZEA producing fungi and the synthesis of mycotoxins. On the contrary, the temperate and dry climate of the other years supported the growth of FB1-producing fungi.

Climate↗
PubMed2001

Occurrence of ochratoxin A in Italian wines.

A total of 96 red wines and 15 white dessert wines produced mostly in the years 1995-97 in 19 Italian regions were analysed for ochratoxin A (OTA). The amount of OTA ranged from < 1 to 3856 ng/l the median (mean) was found to be 90 (419) ng/l for the red wines and 8 (736) ng/l for the white dessert wines. Our survey shows that the geographic region of origin has a strong influence on OTA contamination, both for red and for dessert wines: in fact, wines produced in southern Italy were markedly more contaminated. The overall median (mean) OTA concentration in the red wines produced in the four Italian areas (northwest, northeast, centre and south) was 2 (11), 90 (81), 134 (295) and 1264 (1233) ng/l. The same trend was observed for the white dessert wines: OTA concentrations of over 1000 ng/l were found in four out of five samples from southern Italy (1185, 2454, 3477, 3856 ng/l), while central and northern samples showed very low contamination. The contribution of wine to mean daily OTA intake can be considered negligible in the case of people drinking wine manufactured in northern and central Italy; this is not true if a medium drinker constantly consumes red wine produced in southern Italy in this case wine alone could supply the diet with an amount of OTA equal to or even above the tolerable daily intake of 5 ng/kg body weight recommended by the Scientific Committee on Food of the European Commission.

Chromatography, Affinity↗
PubMed2000

Pharmacokinetics of vancomycin administered as prophylaxis before cardiac surgery.

Vancomycin concentrations in serum, tissues, and sternum, administered as prophylaxis to patients during coronary artery bypass surgery, were measured. Vancomycin (15 mg/kg) was administered to 15 patients 1 hour before skin incision. Blood, tissue, and sternum samples were collected before, during, and after bypass. The concentration in serum at the end of infusion was 55.1 +/- 22.8 microg/mL, the mean elimination half-life was 9 +/- 4 hours, the areas under the concentration-time curve (AUC) from 0 to 12 hours and from 0 to infinity were 90.6 +/- 25.1 and 289.7 +/- 86.5 microg/h per mL, respectively, the mean residence time (MRT) was 11.9 +/- 5.0 hours, the mean volume of distribution was 51.1 +/- 12.2 L, and the total clearance was 78.3 +/- 32.6 mL/min. Vancomycin concentrations in serum, tissues, and sternum during the operation were greater than the MIC90 for most staphylococci and ranged from 16 to 55 microg/mL in serum and from 4 to 39 microg/g in sternum and tissues.

Adult↗
PubMed1995

Anti-nutritional factors of Datura in feedstuffs.

Soybean seed, linseed, some cereals seeds, and their by-products are infected by Datura seed weed of different varieties. The most common Datura spp. noxious to the farm animals are D. stramonium (atropine alkaloid) and D. ferox (scopolamine, 98-100% of total alkaloids) mainly present in Europe and South America, respectively. The presence of alkaloids from Datura seeds in feedingstuffs may be responsible for chronic and/or subclinical toxic effects; acute poisoning from Datura seeds are rare. Pigs are the most sensitive animals to Datura poisoning, followed by cattle, horses, and chickens. Sheep and rabbits are indifferent to atropine presence in food because they synthesize the atropine esterase enzyme. The progressive atropine poisoning in pigs leads to a reduction of feed intake and growth, gastrointestinal motility and secretory activity, extreme mouth dryness, increased respiration and cardiac rate, pupil dilation, etc. Clinical symptoms are partly similar among different species. Toxic effects from Datura alkaloids presence in feeds showed possible variability of alkaloids content tolerated by pigs. In our recent trials, the threshold limit in pigs (20-60 kg live weight) was 1.5 mg alkaloids/kg of feed (1.21 mg alkaloids/kg l.w.75).

Alkaloids↗
PubMed1994

Transfer kinetics and coefficients of 90Sr, 134Cs, and 137Cs from forage contaminated by Chernobyl fallout to milk of cows.

A experiment was conducted to study kinetics, transfer coefficients, and biological half-lives of 90Sr, 134Cs, and 137Cs from feed to milk. A cow was fed a diet containing alfalfa hay contaminated by Chernobyl fallout for 14.5 wk. The time-dependent activity in milk was approximated by a two-compartment model with fast biological half-lives of 2, 0.9, and 1 d and slow biological half-lives of 36.9, 8.7, and 12.4 d for 90Sr, 134Cs, and 137Cs, respectively. The transfer coefficients determined in the experiment were 0.0008 d L-1 for 90Sr, 0.0029 d L-1 for 134Cs, and 0.0031 d L-1 for 137Cs. The biological elimination phases of 134Cs and 137Cs were described by a two-compartment model while a one-compartment model was proposed for 90Sr.

Accidents↗
PubMed1993

Effects of yeast on dairy cow performance, ruminal fermentation, blood components, and milk manufacturing properties.

Effect of dietary yeast culture on milk production and composition, ruminal fermentation, blood parameters, and milk manufacturing properties of 24 midlactation Holstein-Friesian cows was determined in a 6-wk experiment. The control diet (DM) consisted of 30% corn silage, 22% alfalfa hay, and 48% concentrate. After a 2-wk preliminary period, cows were assigned in equal numbers to either 0 or 10 g/d of yeast culture for the remainder of the 4-wk study on the basis of age, DIM, and pretrial milk production. Production of milk (26.2 vs. 25.4 kg/d), FCM (23.6 vs. 21.6 kg/d), and milk fat (.90 vs. .78 kg/d) was increased significantly by dietary yeast culture. No differences were significant for milk composition. Molar proportion of acetate and acetate:propionate ratio in ruminal liquor tended to be higher in cows fed yeast culture. Total VFA concentration in ruminal fluid was not different between treatments. Manufacturing properties of milk and blood plasma components were not affected adversely by added dietary yeast culture.

Ammonia↗
PubMed1989

Prevalence of polycystic ovaries in women with acne.

The prevalence of polycystic ovaries was determined by pelvic ultrasound imaging in 119 women (mean age, 23.6 +/- 6.06 years; range, 14-45 years) with acne but with no menstrual disorders, obesity, or hirsutism, and in 35 healthy controls (mean age, 25 +/- 5.8 years; range, 21-40 years). Polycystic ovaries were found in 54 out of 119 patients with acne (45.37%) and in 6 out of 35 controls (17.14%). The results of this study indicate that polycystic ovaries are common in women with acne and not necessarily associated with menstrual disorders, obesity, or hirsutism.

Acne Vulgaris↗
PubMed1986

Hansen's disease: a new endemic focus in the Piacenza Province? A description of four diagnosed cases by cutaneous biopsy.

Four cases of Hansen's disease (two lepromatous leprosy, one tuberculoid leprosy and one indeterminate leprosy) diagnosed from 1982 to today in Piacenza with histological and ultrastructural data are described in this study. Two cases (one lepromatous leprosy and one indeterminate leprosy) are probably imported, while the other two are apparently autochthonous. In all the cases the diagnosis or the suspicion of the disease are triggered after histological examination of the cutaneous biopsy, without any pre-existing clinical suspicion. In the discussion of the epidemiological significance of the number of cases the authors hypothesize the possible formation of an endemic area in Piacenza and intend to call attention of medical officials to the alarming fact of the probable existence of Hansen's disease in Italy.

Aged↗
PubMed1978

[Influence of pyridoxal-5'-phosphate on responses of isolated coronary arteries to noradrenaline, in the presence of pyrogallol].

The effect of PLP on the noradrenaline-induced relaxation of coronary arteries was studied in vitro, after known inhibitor of COMT, Pyrogallol. Relaxation of response to noradrenaline were increased by PLP. Pyrogallol potentiated responses of coronary strips to noradrenaline and also reduced or abolished the enhancing effects of PLP. It is concluded that PLP enhances the response of coronary smooth muscle to noradrenaline by inhibiting a enzymatic pathway for the inactivation of catecolamines.

Animals↗