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A Lombardi

Publications and source records attributed to A Lombardi.

At least 37 records · Page 2Linked to original sources
PubMed2002

Procalcitonin as an early marker of postoperative infectious complications.

BACKGROUND: Procalcitonin (PCT) is a new marker for severe infection that is supposed to have a useful role in the early detection of bacterial infection in the perioperative period. AIM OF THE STUDY: to test the hypothesis that PCT is useful as an early marker of postoperative infectious complications. METHODS: Thirty-three patients were submitted to major abdominal interventions that comprehend an intestinal resection (mean age: 49.9+/-19.3 years; 19 males, 14 females). PCT was tested at 4 times: T1=preoperative; T2=6 hours after starting interventions; T3=24 hours after; T4=48 hours after. STATISTICAL: "t"-Student test and Pearson correlation. RESULTS: In the postoperative course 11 patients had infectious complications that were: 3 wound infections, 2 positive haemocolture, 1 pneumonia, 3 deep abdominal infections, 2 anastomotic dehiscences. In these patients only the 24 hours PCT assay at T3 was higher than in the other patients that had not complications (microgram/ml 4.74+/-3.8 vs 1.22+/-0.8; p<0.0001). The cut off value of 1 ng/ml has a sensibility of 70% and a specificity of 81%. CONCLUSIONS: PCT detection appear to be an important aid for early diagnosis of postoperative infectious complications when it is used with the other indexes.

Bacterial Infections↗
PubMed2001

Toward the de novo design of a catalytically active helix bundle: a substrate-accessible carboxylate-bridged dinuclear metal center.

De novo design of proteins provides an attractive approach to uncover the essential features required for their functions. Previously, we described the design and crystal structure determination of a di-Zn(II) complex of "due-ferri-1" (DF1), a protein patterned after the diiron-dimanganese class of redox-active proteins [Lombardi, A.; Summa, C.; Geremia, S.; Randaccio, L.; Pavone, V.; DeGrado, W. F. Proc. Natl. Acad. Sci. U.S.A. 2000, 97, 6298-6305]. The overall structure of DF1, which contains a carboxylate-bridged dinuclear metal site, agrees well with the intended design. However, access to this dimetal site is blocked by a pair of hydrophobic leucine residues (L13 and L13'), which prevent facile entry of metal ions and small molecules. We have now taken the next step in the eventual construction of a catalytically active metalloenzyme by engineering an active site cavity into DF1 through the replacement of these two leucine residues with smaller residues. The crystal structure of the dimanganous form of L13A-DF1 indeed shows a substrate access channel to the dimetal center. In the crystal structure, water molecules and a ligating dimethyl sulfoxide molecule, which forms a monatomic bridge between the metal ions, occupy the cavity. Furthermore, the diferric form of a derivative of L13A-DF1, DF2, is shown to bind azide, acetate, and small aromatic molecules.

Amino Acid Sequence↗
PubMed2001

Proteolytic, lipolytic and molecular characterisation of Yarrowia lipolytica isolated from cheese.

This work studied the qualitative and quantitative proteolytic and lipolytic activities of Yarrowia lipolytica strains isolated from two cheese types. Randomly amplified polymorphic DNA-PCR (RAPD-PCR) analysis was used to compare the cheese strains of Y. lipolytica with strains isolated from other food products and with the type strain of the species in order to investigate the genetic diversity and occurrence of specific environmental groups. Diversity of proteolytic and especially lipolytic activity within Y. lipolytica strains isolated from dairy products was observed. In particular, the degree of specificity for saturated or unsaturated fatty acids as well as for even- or odd-numbered carbon free fatty acids (FFAs) varied among the strains. The RAPD-PCR profiles showed low genetic relatedness between many of the food isolates and the type strain of the species. Such genetic variability needs to be further evaluated. Most of the Y. lipolytica strains appeared to be specific to the particular environment from which they were isolated. However, phenotypic characteristics having technological importance in dairy products and, particularly, lipolytic activities did not correspond to the genetic differences observed by RAPD-PCR analysis.

Cheese↗
PubMed2001

Some probiotic properties of yeast isolates from infant faeces and Feta cheese.

Yeast isolates from infant faeces and Feta cheese were characterized to species level by phenotypic criteria, Randomly Amplified Polymorphic DNA (RAPD)-PCR and mitochondrial DNA (mt-DNA) restriction analysis. Results suggested that there is a good agreement between phenotypic characterization of yeasts and RAPD-PCR at species level; in addition, RAPD-PCR as well as mt-DNA restriction analysis provided good discrimination at strain level. Some technological and probiotic properties of selected strains were also investigated. The test strains exhibited lipolytic and proteolytic activities. They also tolerated low pH and survived satisfactory in gastric juice in vitro as well as in the presence of bile. In general, the isolates from faeces were more resistant to low pH and bile than those from Feta cheese. Selected strains could be used as starter supplements for industrial fermentations.

Cheese↗
PubMed2001

Effect of Saquinavir on proliferation and telomerase activity of human peripheral blood mononuclear cells.

The present study describes the effect of Saquinavir on proliferation, interferon-gamma production and telomerase activity of non-stimulated, or activated non-adherent mononuclear cells (NAMNC), obtained from peripheral blood of healthy donors. Fresh NAMNC, non-stimulated or activated in vitro with PHA or with a mixture of monoclonal antibodies against CD3 and against CD28 membrane antigens (in order to obtain prevalent T cell responses), were exposed to Saquinavir before or at the time of mitogenic stimulation. Control and treated cells were tested for DNA synthesis (3H-thymidine incorporation), interferon-gamma production and telomerase activity (TRAP assay). The results indicate that Saquinavir is able to increase proliferation and interferon-gamma release in PHA-stimulated NAMNC, and telomerase activity either in non-stimulated and in PHA or antibody-activated cells. These results suggest that the activity against HIV infection afforded by Saquinavir, could be corroborated by its effects on the host. These include its adjuvant activity on mitogen-induced responses of lymphocytes, and its possible antagonistic effects against lymphoid cell senescence, through telomerase activation.

Antibodies, Monoclonal↗
PubMed2001

Control of energy metabolism by iodothyronines.

One of the most widely recognized effects of thyroid hormones (TH) in adult mammals is their influence over energy metabolism. In the past, this has received much attention but, possibly because of the complex mode of action of thyroid hormones, no universally accepted mechanism to explain this effect has been put forward so far. Significant advances in our understanding of the biochemical processes involved in the actions of TH have been made in the last three decades and now it seems clear that TH can act through both nuclear-mediated and extranuclear-mediated pathways. TH increase energy expenditure, partly by reducing metabolic efficiency, with control of specific genes at the transcriptional level, being is thought to be the major molecular mechanism. However, both the number and the identity of the thyroid-hormone-controlled genes remain unknown, as do their relative contributions. The recent discovery of uncoupling proteins (UCPs) (in addition to UCP1 in brown adipose tissue) in almost all tissues in animals, including humans, has opened new perspectives on the understanding of the mechanisms involved in the regulation of energy metabolism by thyroid hormones. Other approaches have included the various attempts made to attribute changes in respiratory activity to a direct influence of thyroid hormones over the mitochondrial energy-transduction apparatus. In addition, an increasing number of studies has revealed that TH active in the regulation of energy metabolism include not only T3, but also other iodothyronines present in the biological fluids, such as 3,5-diiodothyronine (3,5-T2). This, in turn, may make it possible to explain some of the effects exerted by TH on energy metabolism that cannot easily be attributed to T3.

Animals↗
PubMed2001

The assessment of bone mass in men.

Bone mineral density (BMD) is widely used in postmenopausal women to identify who should be given therapy for prevention and treatment of osteoporosis and to monitor the efficacy of treatment. There is still uncertainty about how to interpret BMD in men, and few prospective studies exist on the relationship between BMD and fracture risk. Men should be considered for measurement of BMD if they have suffered low trauma fractures, have prevalent vertebral deformities, have radiographic osteopenia, are over age 75, or have conditions that increase their risk for bone loss, such as hypogonadism, glucocorticoid use, or generally poor health. There is insufficient information to recommend a more widespread BMD screening. The World Health Organization has developed criteria for interpreting BMD which are widely used. Patients with BMD at least 2.5 SD below the young adult mean (T-score < -2.5) have osteoporosis, and those with BMD between 1 and -2.5 SD below the young adult mean (-2.5 < T-score < -1.0) have osteopenia. However, the BMD criteria that should be used to identify men in need of therapeutic intervention are still debated. Using male-specific hip BMD cutoffs, approximately 3-6% of U.S. men 50 years and older were estimated to have osteoporosis and 28-47% to have osteopenia. The corresponding figures in women were 13-18% with osteoporosis and 37-50% with osteopenia. Greater accumulation of skeletal mass during growth, slower rate of bone loss, and shorter life expectancy in men contribute to the lower prevalence of osteoporosis relative to women.

Bone Density↗
PubMed2001

D-dimer increase after percutaneous transluminal angioplasty and clinical recurrence after primary revascularization in acute myocardial infarction? A pilot study.

It has been reported that the increase of plasminogen activator inhibitor-1 activity immediately after elective coronary angioplasty is related to subsequent clinical recurrence in patients with chronic coronary artery disease. The aims of our study were to evaluate the behavior of plasminogen activator inhibitor-1 and D-Dimer after revascularization in acute myocardial infarction patients treated with angioplasty and stenting and if this behavior is predictive of subsequent clinical recurrence. D-Dimer and plasminogen activator inhibitor-1 activity were evaluated in two groups of patients. Group 1 consisted of 54 consecutive patients undergoing primary angioplasty for acute myocardial infarction and Group 2 consisted of 48 patients undergoing elective angioplasty. Patients underwent control coronary angiography only in the case of clinical recurrence and/or positivity of provocative tests. D-Dimer and plasminogen activator inhibitor-1 baseline levels were significantly higher in group 1 than in group 2 (P<0.0005 and P<0.05, respectively). The percentage of group 1 patients with a post-procedural increase in D-Dimer was significantly higher among those with subsequent clinical recurrence with restenosis (61%) than among those with no recurrence (25%, P<0.05). No difference was observed in group 2. The percentage of group 2 patients in whom no decrease of plasminogen activator inhibitor-1 was observed after angioplasty was significantly higher (83%) among those with subsequent recurrence than among those with no recurrence (38%, P<0.05). This pattern was not observed in group 1. In conclusion, the role of early changes in plasminogen activator inhibitor-1 in predicting clinical recurrence after primary angioplasty in acute myocardial infarction patients is less clear than that observed after elective angioplasty. A significant role seems to be played by a more-marked clotting activation with increased fibrin formation.

Adult↗
PubMed2001

Development of the Specific and Random Amplification (SARA)-PCR for both species identification of enterococci and detection of the vanA gene.

A rapid and reliable polymerase chain reaction (Specific and Random Amplification (SARA)-PCR) has been developed to identify enterococcal species and to detect the vanA gene in one single reaction. This technique was based on the use of the primer set previously designed to amplify a part of the vanA gene (Dutka-Malen et al., J. Clin. Microbiol., 33 (1995) 24-27). In the chosen low stringency conditions complex patterns were obtained, with a sharp band of approximately 700 bp in cases where the vanA gene was present. Discrimination at the species and strain level was achieved by applying the SARA-PCR assay to a collection of 55 enterococcal isolates and type strains. Simultaneously the vanA gene was detected in all strains showing high resistance to vancomycin.

Animals↗
PubMed2001

Rapid identification of Enterococcus durans and Enterococcus hirae by PCR with primers targeted to the ddl genes.

Species-specific PCR assays with primers targeted to D-alanine:D-alanine ligase (ddl) encoding genes were developed for the identification of Enterococcus durans and E. hirae. The specificity of the primers was validated in a multiplex PCR on well characterised E. durans (n=30) and E. hirae (n=16) strains, all of which were identified correctly. This PCR procedure offers a reliable and rapid alternative to conventional phenotypic methods for speciation of these enterococci of growing clinical importance.

Bacterial Typing Techniques↗
PubMed2001

Phenotypic and genetic diversity of enterococci isolated from Italian cheeses.

In the present study, 124 enterococcal strains, isolated from traditional Italian cow, goat and buffalo cheeses, were characterized using phenotypic features and randomly amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). The RAPD-PCR profiles obtained with four primers and five different amplification conditions were compared by numerical analysis and allowed an inter- and intraspecific differentiation of the isolates. Whole cell protein analysis by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was used as a reference method for species identification. The strains were identified as Enterococcus faecalis (82 strains), E. faecium (27 strains), E. durans (nine strains), E. gallinarum (four strains) and E. hirae (two strains). Species recognition by means of RAPD-PCR was in agreement with the SDS-PAGE results except for eight strains of E. faecium that clustered in separated groups. On the other hand, phenotypic identification based on carbohydrate fermentation profiles, using the rapid ID 32 STREP galleries, gave different results from SDS-PAGE in 12.1% of the cases. The majority of the strains had weak acidifying and proteolytic activities in milk. One E. faecium strain showed vanA (vancomycin resistance) genotype while four strains showed a beta-haemolytic reaction on human blood. Several strains showed antagonistic activity towards indicator strains of Listeria innocua, Clostridium tyrobutyricam and Propionibacterium freudenreichii subsp. shermanii.

Animals↗
PubMed2001

Serum cholinesterase is an early and sensitive marker of graft-versus host-disease (GVHD) and transplant-related mortality (TRM).

Serum cholinesterase (CHE) has been reported to be a significant indicator of liver function and prognosis in patients with cirrhosis. On the other hand, liver complications are frequent following allogeneic stem cell transplantation (HSCT). We therefore tested whether CHE was predictive of graft-versus-host disease and outcome in HSCT recipients. We studied 689 patients receiving a HSCT from an HLA-identical sibling (SIB) (n = 511), an alternative donor (n = 173) or a syngeneic twin (n = 5). Acute graft-versus-host disease (GVHD) was scored as 0-I, II, III-IV in 325 (47%), 279 (41%), and 85 patients (12%) respectively; 190 (28%) patients died of transplant-related complications (TRM). On day -7 the median CHE serum level was comparable in patients who either survived or died of TRM (5900 IU/l). On day 0, serum CHE levels were respectively 2310 and 2120 IU/l (P = NS) indicating the impact of the conditioning regimen. On day +7 after HSCT, the median level for surviving patients was 2598 IU/l vs 2309 IU/l for patients who subsequently died (P = 0.0002), on day +21 CHE levels were respectively 3348 vs 2528 IU/l (P < 0.00001), on day +50, 3575 vs 2358 IU/l (P < 0.00001) and on day +100 4193 vs 2729 IU/l (P < 0.00001). CHE levels on day +50 strongly correlated with aGVHD (3803 vs 3070 vs 1933 IU/l for patients with GVHD grade 0-I, II, and III-IV, respectively (P < 0.00001) and relapse (3569 for patients relapsing vs 3115 IU/l for patients not relapsing, P = 0.0006). In conclusion, (1) serum cholinesterase is a simple and reliable marker of acute GVHD and transplant-related complications; and (2) high CHE levels on day +50 predict relapse. If confirmed, the latter patients may be eligible for early reduction of immunosuppressive therapy.

Adolescent↗
PubMed2001

RAPD-PCR characterization of lactobacilli isolated from artisanal meat plants and traditional fermented sausages of Veneto region (Italy).

AIMS: The study was carried out to evaluate the use of randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) as a method for the identification of lactobacilli isolated from meat products. METHODS AND RESULTS: RAPD-PCR with primers M13 and D8635 was applied to the identification and intraspecific differentiation of 53 lactobacilli isolates originating from traditional fermented sausages and artisanal meat plants of the Veneto region (Italy). Most of the isolates were assigned to the species Lactobacillus sakei and Lact. curvatus; differentiation of groups of strains within the species was also possible. CONCLUSION: RAPD-PCR could be applied to the identification of lactobacilli species most commonly found in meat products. SIGNIFICANCE AND IMPACT OF THE STUDY: The method, which is easy and rapid to perform, could be useful for the study of the lactobacilli populations present in fermented sausages, and could help in the selection of candidate strains to use as starter cultures in meat fermentation.

Bacterial Typing Techniques↗
PubMed2001

Antimicrobial activity of thiamphenicol-glycinate-acetylcysteinate and other drugs against Chlamydia pneumoniae.

Chlamydia pneumoniae is responsible for respiratory tract infections of both upper and lower respiratory tract. Although this bacterium is one of the most wide-spread pathogens of man, there are limited data on the antibiotic treatment of C. pneumoniae infections. The aim of this study has been to evaluate the in vitro activity of thiamphenicol glycinate acetylcysteinate (TGA, CAS 20192-91-0) in comparison with molecules with established activity against C. pneumoniae, as well as macrolides and quinolones. The results have shown that TGA and clarithromycin (CAS 81103-11-9) are the most active drugs tested, but it is important to underline that the minimal inhibitory concentration (MIC) ranges of TGA are very much lower than the breakpoint of thlamphenicol for the respiratory pathogens. In conclusion, the good antimicrobial in vitro activity of TGA against C. pneumoniae together with its in vivo characteristics, in particular the high concentration reached in lung and the combination with the mucolytic agent N-acetylcysteine (NAC, CAS 616-91-1), can make a valid choice in the treatment of respiratory tract infections caused by C. pneumoniae. These findings need further evaluation by clinical studies.

Acetylcysteine↗
PubMed2001

A survey of yeasts in traditional sausages of southern Italy.

The evolution of the yeast population during manufacturing and ripening of 'salsiccia sotto sugna', a typical salami of the Lucania region (southern Italy), was investigated. Four different batches, produced in four farms in Lucania, were studied. Each batch showed a specific yeast population, and the most frequently isolated yeasts belonged to Debaryomyces hansenii and its anamorph Candida famata, and Rhodotorula mucilaginosa. Yarrowia lipolytica was isolated from three sausage batches. The Y. lipolytica isolates were further characterised, in particular for their lipolytic activity on pork fat. Lipolytic activity was maximal at pH 5.5, with oleic and palmitic acids as major free fatty acids produced. The use of randomly amplified polymorphic DNA-polymerase chain reaction allowed the detection of a high genetic heterogeneity among the isolates phenotypically assigned to the species Y. lipolytica.

Animals↗
PubMed2001

Saquinavir up-regulates telomerase activity in lymphocytes activated with monoclonal antibodies against CD3/CD28.

The present study describes the effect of the HIV protease inhibitor saquinavir on telomerase activity and interferon-gamma (IFN-gamma) production of nonadherent mononuclear cells (NA-MNC). Cells obtained from peripheral blood of healthy donors were exposed in vitro to a mixture of monoclonal antibodies against CD3 and CD28 membrane antigens in order to activate prevalently T cell subsets. Treatment with saquinavir was performed at the time of cell stimulation. Thereafter, NA-MNC were tested for telomerase activity (TRAP assay) and interferon-gamma production up to 7 days later. The results show that saquinavir up-regulates telomerase activity and IFN-gamma release in activated NA-MNC. These observations suggest that the anti-HIV effects of saquinavir could be accompanied by other immunopharmacological properties, influencing some aspects of the functional activity of immunocompetent cells. These include possible antagonistic effects against lymphocyte senescence, through telomerase activation, and a potentiating activity on the production of IFN-gamma following T cell activation.

Antibodies, Monoclonal↗
PubMed2001

Uncoupling protein-3 is a molecular determinant for the regulation of resting metabolic rate by thyroid hormone.

Thyroid hormones increase energy expenditure, partly by reducing metabolic efficiency. The control of specific genes at the transcriptional level is thought to be the major molecular mechanism. However, both the number and the identity of the thyroid hormone-controlled genes remain unknown, as do their relative contributions. Uncoupling protein-3, a recently identified member of the mitochondrial transporter superfamily and one that is predominantly expressed in skeletal muscle, has the potential to be a molecular determinant for thyroid thermogenesis. However, changes in mitochondrial proton conductance and resting metabolic rate after physiologically mediated changes in uncoupling protein-3 levels have not been described. Here, in a study on hypothyroid rats given a single injection of T(3), we describe a strict correlation in terms of time course between the induced increase in uncoupling protein-3 expression (at mRNA and protein levels) and decrease in mitochondrial respiratory efficiency, on the one hand, and the increase in resting metabolic rate, on the other. First, we describe our finding that uncoupling protein-3 is present and regulated by T(3) only in metabolically relevant tissues (such as skeletal muscle and heart). Second, we follow the time course (at 0, 6, 12, 24, 48, 65, 96, and 144 h) of both uncoupling protein-3 mRNA levels and mitochondrial uncoupling protein-3 density in gastrocnemius muscle and heart. In both tissues, the maximal (12-fold) increase in uncoupling protein-3 density was reached at 65 h. The resting metabolic rate [lO(2)(kg(0.75))(-1)h(-1)] showed the same time course, and at 65 h the increase vs. time zero was 45% (1.316 +/- 0.026 vs. 0.940 +/- 0.007; P < 0.001). At the same time point, gastrocnemius muscle mitochondria showed a significantly higher nonphosphorylating respiration rate (nanoatoms of oxygen per min/mg protein; increase vs. time zero, 40%; 118 +/- 4 vs. 85 +/- 9; P < 0.05), whereas the membrane potential decreased by 8% (168 +/- 2 vs. 182 +/- 4; P < 0.05). These data are diagnostic of mitochondrial uncoupling. The results reported here provide the first direct in vivo evidence that uncoupling protein-3 has the potential to act as a molecular determinant in the regulation of resting metabolic rate by T(3).

Animals↗