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Biomedical subjects

P Giardina

Publications and source records attributed to P Giardina.

At least 19 recordsLinked to original sources
PubMed2002

Umbilical cord blood collection in Cesarean section: a comparison before and after placental delivery.

Fetal stem cells transplants depend on nucleated cells from fetal blood. This study was a prospective randomized trials to compare the collection of fetal blood by gravity into a bag containing anticoagulant, before and after delivery of the placenta. The obstetric and the newborn characteristics in the two group were not significantly different. The mean volume of fetal blood collected while the placental was still in utero was 74.93+/-7.1 ml as against 35.78+/-3.6 ml for collection of fetal blood after delivery of the placenta.

Cesarean Section↗
PubMed2002

Comparison of dexa and ultrasonometry in the measurement of bone density.

The aim of our study was to evaluate the diagnostic agreement between quantitative sonography of the calcaneum (QUS) and dual energy X-ray absorptiometry (DEXA) of the spine and femur. 153 women enrolled in our study and were divided in three groups. Group A was composed of women aged between 45 and 55, Group B of women of 56-66 and Group C of women 67-77. Mean height cm 164+/-2.8; mean weight kg 68+/-3.2. The most concordant results were obtained in group B. This suggests that QUS screening for osteoporosis may be suitable for the "younger" perimenopausal patient.

Absorptiometry, Photon↗
PubMed2002

Two CD34+ stem cells from umbilical cord blood enrichment methods.

The authors describe the relation between clamping time and blood volume collected, and two enrichment systems of CD34+ stem cells from umbilical cord blood, to determine an excellent recovery with high proliferate ability and bone marrow reconstitution. After an obstetrician-based cord blood collection, the purification of stem cells was performed either with a combination of monoclonal antibodies (negative selections) using the Stem Sep method, or with a positive cells selection thanks to their surface CD34 antigens, using the Mini Macs system. An excellent recovery of hematopoietic progenitors, burst-forming unit erythroid, colony-forming unit granulocyte and macrophage, and colony-forming unit granulocyte, erythroid, monocyte, and macrophage, inversely related to the rising of clamping time, was performed with the Mini Macs system (54% of colonies, with a 90% purity), while with Stem Sep method, hematopoietic progenitor recovery was 35% (with an 80% purity). By applying early clamping of the umbilical cord blood a greater number of CD34+ cells was obtained and their clonogenic activity increased with enrichment. This is particularly useful, considering that the number of CD34+ stem cells contained in a unit of placental blood is enough for transplanting to a child, but not for an adult engraftment. Thus, using this method, a larger number of CD34+ stem cells can be obtained, which increases the possibility to reduce graft versus host disease also in adult patients, producing survival rates similar to the ones obtained with transplantation of bone marrow from unrelated donors.

Antibodies, Monoclonal↗
PubMed2002

VLA-2 and VLA-5 cell adhesion molecules expression in CD34+ cells from umbilical cord blood and from bone marrow.

BACKGROUND/AIMS: Umbilical cord blood contains a large number of early hematopoietic cells with high proliferating capacity, that has been used as an alternative to bone marrow transplantation. The aim of this study is to investigate the number of two cell adhesion molecules in cord blood and in bone marrow. METHODS: We investigated two integrins, named VLA-2 and VLA-5 (Very Late Appearing Antigen), expressed in the surface of CD34+ cells. The CD34+ cells, isolated with MACS CD34+ isolation kit, were labelled with the appropriate monoclonal antibodies. RESULTS: Cell adhesion molecules showed highly expressed in both cord blood and bone marrow CD34+ cells. CONCLUSION: There are no significant differences between the two sources of CD34+ populations.

Antigens, CD34↗
PubMed2002

Influence of the kind of delivery on umbilical cord blood collection.

From December 1999 to February 2001, the Microbiological and Gynaecological Science Department of the University of Catania has been involved in the collection of umbilical cord blood samples. Eight hundred and sixty-three cord blood units were collected and sent to Sciacca's UCB bank. Among them, 429 were collected from newborns delivered vaginally, while the remaining were collected from Caesarean sections. The aim of this study was to evaluate the difference between umbilical cord blood samples collected during a vaginal delivery and those from a Caesarean section. In particular, the blood volume collected and cord blood CD34+ stem cell count were considered. The method of blood collection consisted of puncturing the umbilical cord vein with an 18-gauge needle and withdrawing the blood into a sterile bag immediately after clamping and newborn assistance. The blood was collected when the placenta was still in utero and the indication to the kind of delivery was, independently of the study, according to obstetrical good practice. The results of the analysis showed that the cord blood volume and the number of CD34+ cells collected were similar for the two groups. The higher median volume of blood collected from infants delivered by Caesarean section seems mainly due to the different clamping time, rather than to the kind of delivery.

Blood Specimen Collection↗
PubMed2002

Influence of sport and low animal saturated fats intake diet on lipid dismetabolisms in postmenopausal women.

BACKGROUND: An important aetiopathogenetic factor leading to menopausal age pathologies (such as hypertension, diabetes, cardiovascular diseases and so on) is certainly represented by the worsening of lipid dismetabolism. This condition is generally characterized by an increase in total mean cholesterol levels, LDL-cholesterol (low density lipoprotein-cholesterol), VLDL-cholesterol (very low density lipoprotein-cholesterol), triglycerides, with reduction of HDL-cholesterol (high density lipoprotein-cholesterol) mean levels. All these metabolic modifications are triggered or increased by the hypoestrogenemia typical of postmenopausal age. The aim of our study was to evaluate the influence on postmenopausal women's lipid metabolism of a low contribution of animal saturated fat diets, associated with physical training. METHODS: We enrolled in our study 36 mild hypercholesterolemic postmenopausal women (non smokers and not complaining of hypertension and diabetes) and we put them through aerobic training, consisting of 1 hour of a light continuous run, repeated 4 times per week. The final control of their metabolic status and of their lipid order was executed after 6 months, but during this period, all the women were observed bi-weekly or monthly, to assure a high uniform compliance in the group. None of the women enrolled took specific drugs for the lipid metabolism during the study. RESULTS: After 6 months from the beginning of the diet, with associated physical training, an important weight loss was observed. Increases of HDL-cholesterol mean levels (p<0.05) associated with a decrease of total cholesterol mean levels (p<0.05) were reported in all the subject examined. A statistically non-significant decrease in LDL and VLDL cholesterol mean levels was also noticed. CONCLUSIONS: A mild lipid dysmetabolism in postmenopause may be corrected advantageously by an opportune diet associated with moderate, but constant, physical training.

Cholesterol↗
PubMed2001

Roles of two white-rot basidiomycete fungi in decolorisation and detoxification of olive mill waste water.

A Phanerochaete chrysosporium strain was isolated from Moroccan olive mill waste water (OMW) and its ability to degrade OMW in different culture conditions was investigated and compared to that of Pleurotus ostreatus. The results indicated that Ph. chrysosporium isolate is more efficient than Pl. ostreatus in decolorising and detoxifying OMW in the presence of added nutrients. Ph. chrysosporium is able to remove more than 50% of the colour and phenols from OMW within 6 days of incubation, whereas Pl. ostreatus needs more than 12 days to reach similar results in the same conditions. Many factors affecting the treatment of diluted OMW (20%) by Ph. chrysosporium were studied, including the effects of added nutrients, initial pH, temperature and inoculated biomass. Once the optimisation of 20% OMW biodegradation process had been set up, higher OMW concentrations (50%) were tested. The results show that the fungus is capable of reducing all parameters analysed (colour A395, phenol content and chemical oxygen demand) by at least 60%, after only 9 days of growth.

Basidiomycota↗
PubMed2001

Structural and kinetic characterization of native laccases from Pleurotus ostreatus, Rigidoporus lignosus, and Trametes trogii.

A comparative study has been performed on five native laccases purified from the three basidiomycete fungi Pleurotus ostreatus, Rigidoporus lignosus, and Trametes trogii to relate their different catalytic capacities to their structural properties. Spectroscopic absorption features and EPR spectra at various pH values of the five enzymes are very similar and typical of the blue oxidases. The analysis of the dependence of kinetic parameters on pH suggested that a histidine residue is involved in the binding of nonphenolic substrates, whereas both a histidine and an acidic residue may be involved in the binding of phenolic compounds. His and an Asp residue are indeed found at the bottom of a cavity which may be regarded as a suitable substrate channel for approaching to type 1 copper in the 3D homology models of the two laccases from Pleuorotus ostreatus (POXC and POXAlb) whose sequences are known.

Benzothiazoles↗
PubMed2001

Placing the newborn on the maternal abdomen increases the volume of umbilical cord blood collected.

Haematopoietic stem cell transplantation is an important therapy for certain haematological and malignant disorders. Umbilical cord blood contains a high proportion of potentially transplantable haematopoietic progenitor cells. However, the use of cord blood stem cell transplantation is limited by the low number of stem cells obtainable from a single cord blood donor. The aim of our study was to investigate the possibility that procedures during delivery might influence the number of umbilical cord blood haematopoietic progenitor cells available for transplantation. We assessed the effects of upper and lower positions of the newborn infant on the yield of cord blood stem cells in 51 vaginal deliveries. Neonates in the upper position group were placed by the midwife on the maternal abdomen immediately after birth, while those in the lower position group were placed on the delivery table, below the maternal introitus. The total volume of cord blood and the total number of CD34+ cells collected from babies in the upper position group were significantly higher than those from babies in the lower position group. There were no significant differences in cord blood haemoglobin levels and white blood cell counts between the two groups, nor were there any adverse effects in the newborn infants. The simple manoeuvre of placing the newborn on the maternal abdomen after delivery may thus increase the yield of transplantable haematopoietic progenitor cells in cord blood.

Abdomen↗
PubMed2001

Early clamping of umbilical cord blood and foetal CD34 enrichment.

We describe the relation between clamping time and blood volume collected, and two enrichment systems of CD34+ stem cells from umbilical cord blood, in order to determine the criteria for an excellent recovery with high proliferative ability and bone marrow reconstitution. After an obstetrician-based cord blood collection, the purification of stem cells was performed either with a combination of monoclonal antibodies, negative selections, using the Stem Sep method, or with a positive cells selection owing to their surface CD34 antigens, using the Mini Macs system. An excellent recovery of haematopoietic progenitors--burst forming unit erythroid; colony-forming unit granulocyte and macrophage; and colony-forming unit granulocyte, erythroid, monocyte, and macrophage--inversely related to an increase in clamping time, was achieved using the Mini Macs system (54% of colonies with a 90% purity), while the recovery of haematopoietic progenitors was 35% (with a 80% purity) using the Stem Sep method. By clamping umbilical cord blood at an early stage, we obtained a greater number of CD34+ cells, and their clonogenic activity increased with enrichment. This is particularly useful considering that the number of CD34+ stem cells contained in a unit of placental blood is sufficient for transplanting into a child but not for an adult engraftment. Thus, using these methods, we obtain a larger number of CD34+ stem cells. This increases the possibility of reducing graft versus host disease in adult patients and produces survival rates similar to the ones we observed in transplantation of bone marrow from unrelated donors.

Antigens, CD↗
PubMed2001

Purification, characterization, and functional role of a novel extracellular protease from Pleurotus ostreatus.

A new extracellular protease (PoSl; Pleurotus ostreatus subtilisin-like protease) from P. ostreatus culture broth has been purified and characterized. PoSl is a monomeric glycoprotein with a molecular mass of 75 kDa, a pI of 4.5, and an optimum pH in the alkaline range. The inhibitory profile indicates that PoSl is a serine protease. The N-terminal and three tryptic peptide sequences of PoSl have been determined. The homology of one internal peptide with conserved sequence around the Asp residue of the catalytic triad in the subtilase family suggests that PoSl is a subtilisin-like protease. This hypothesis is further supported by the finding that PoSl hydrolysis sites of the insulin B chain match those of subtilisin. PoSl activity is positively affected by calcium. A 10-fold decrease in the K(m) value in the presence of calcium ions can reflect an induced structural change in the substrate recognition site region. Furthermore, Ca(2+) binding slows PoSl autolysis, triggering the protein to form a more compact structure. These effects have already been observed for subtilisin and other serine proteases. Moreover, PoSl protease seems to play a key role in the regulation of P. ostreatus laccase activity by degrading and/or activating different isoenzymes.

Amino Acid Sequence↗
PubMed2001

Adenomyosis and uterus rupture during labor.

A spontaneous uterus rupture occurred during the labour of a 37-week-pregnant woman showing a precocious rupture of membranes. It appeared enlarged and the cut surface of the myometrium showed coarse trabeculations. The histological examination showed a hypertrophic gravidic myometrium with heterogeneous areas of fibrosis and adenomyosis, necrotic decidual foci and hyperplastic cervical canal glands. Our experience suggests that a silent and spontaneous uterine rupture, is possible even in the absence of the principal risk factors.

Adult↗
PubMed2000

Manganese peroxidase isoenzymes produced by Pleurotus ostreatus grown on wood sawdust.

The white rot basidiomycete Pleurotus ostreatus produces two manganese peroxidase (MnP) isoenzymes when grown in solid stationary conditions on poplar sawdust, whereas a lower production of these same enzymes is observed on fir sawdust. Addition of Mn(2+) to poplar culture resulted in a threefold increase of MnP activity; the same addition to fir culture was able to increase tenfold the MnP production. The two MnP isoenzymes (MnP2 and MnP3) were purified from P. ostreatus poplar culture. The isoenzymes differ in their pI values, molecular masses, and N-terminal sequences. MnP3 has the same N-terminal sequence as that of a P. ostreatus MnP previously reported. Both isoenzymes exhibit Mn(2+)-dependent and Mn(2+)-independent peroxidase activities when tested on phenolic substrates. The gene coding for the new isoenzyme MnP2 was cloned and sequenced and the promoter region analyzed. Furthermore, the chromosomal localization of all known P. ostreatus genes was determined.

Amino Acid Sequence↗
PubMed2000

Copper induction of laccase isoenzymes in the ligninolytic fungus Pleurotus ostreatus.

Pleurotus ostreatus is a white rot basidiomycete that produces several extracellular laccase isoenzymes, including phenol oxidase A1b (POXA1b), POXA2, and POXC. POXC was the most abundant isoenzyme produced under all of the growth conditions examined in this study. Copper was the most efficient inducer of laccase activity among the putative inducers tested. The amounts of all of the previously described laccase isoenzymes increased substantially in copper-supplemented cultures. Under these conditions expression of POX isoenzymes was regulated at the level of gene transcription. It is worth noting that poxa1b mRNA was the most abundant induced transcript at all of the growth times analyzed, and the amount of this mRNA increased until day 7. The discrepancy between the poxa1b transcript and protein amounts can be explained by the presence of a high level of the protein in P. ostreatus cellular extract, which indicated that the POXA1b isoenzyme could be inefficiently secreted and/or that its physiological activity could occur inside the cell or on the cell wall. Moreover, the POXA1b isoenzyme behaved uniquely, as its activity was maximal on the second day of growth and then decreased. An analysis performed with protease inhibitors revealed that the loss of extracellular POXA1b activity could have been due to the presence of specific proteases secreted into the copper-containing culture medium that affected the extracellular POXA1b isoenzyme.

Copper↗
PubMed1999

Protein and gene structure of a blue laccase from Pleurotus ostreatus1.

A new laccase isoenzyme (POXA1b, where POX is phenol oxidase), produced by Pleurotus ostreatus in cultures supplemented with copper sulphate, has been purified and fully characterized. The main characteristics of this protein (molecular mass in native and denaturing conditions, pI and catalytic properties) are almost identical to the previously studied laccase POXA1w. However, POXA1b contains four copper atoms per molecule instead of one copper, two zinc and one iron atom per molecule of POXA1w. Furthermore, POXA1b shows an unusually high stability at alkaline pH. The gene and cDNA coding for POXA1b have been cloned and sequenced. The gene coding sequence contains 1599 bp, interrupted by 15 introns. Comparison of the structure of the poxa1b gene with the two previously studied P. ostreatus laccase genes (pox1 and poxc) suggests that these genes belong to two different subfamilies. The amino acid sequence of POXA1b deduced from the cDNA sequence has been almost completely verified by means of matrix-assisted laser desorption ionization MS. It has been demonstrated that three out of six putative glycosylation sites are post-translationally modified and the structure of the bound glycosidic moieties has been determined, whereas two other putative glycosylation sites are unmodified.

Amino Acid Sequence↗
PubMed1997

A novel white laccase from Pleurotus ostreatus.

Two laccase isoenzymes (POXA1 and POXA2) produced by Pleurotus ostreatus were purified and fully characterized. POXA1 and POXA2 are monomeric glycoproteins with 3 and 9% carbohydrate content, molecular masses of about 61 and 67 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis, of about 54 and 59 kDa by gel filtration in native conditions, and of 61 kDa by matrix-assisted laser desorption ionization mass spectrometry (only for POXA1) and pI values of 6.7 and 4.0, respectively. The N terminus and three tryptic peptides of POXA1 have been sequenced, revealing clear homology with laccases from other microorganisms, whereas POXA2 showed a blocked N terminus. The stability of POXA2 as a function of temperature was particularly low, whereas POXA1 showed remarkable high stability with respect to both pH and temperature. Both enzymes oxidize syringaldazine and ABTS (2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) together with a variety of different substituted phenols and aromatic amines with the concomitant reduction of oxygen, but POXA1 is unable to oxidize guaiacol. Both enzymes were strongly inhibited by sodium azide and thioglycolic acid but not by EDTA. UV/visible absorption spectra, atomic adsorption, and polarographic data indicated the presence of 4 copper atoms/mol of POXA2 but only one copper, two zinc, and one iron atoms were found/mol of POXA1. The neutral pI and the anomalous metal content of POXA1 laccase render this enzyme unique in its structural characteristics. The lack of typical absorbance at 600 nm allows its classification as a "white" laccase.

Amino Acid Sequence↗