Leonardo Sechi

Prof. Leonardo Sechi

Dipartimento di Scienze Biomediche, Università degli Studi di Sassari, Italy
orcid

Research Focus & Metrics

Academic Career Length

34Years (1993-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 December 2005 in Annals of Clinical Microbiology and Antimicrobials
Verified
Journal Article
Open access
SAShaik Mahaboob Ali
Shaik Mahaboob Ali
AKAleem Khan
Aleem Khan
IAIrshad Ahmed
Irshad Ahmed
MMM Musaddiq
M Musaddiq
KAKhawaja Shakeel AHMED
Khawaja Shakeel AHMED
NANiyaz Ahmed
Niyaz Ahmed
Background: Eradication of Helicobacter pylori is an important objective in overcoming gastric diseases. Many regimens are currently available but none of them could achieve 100% success in eradication. Eugenol and cinnamaldehyde that are commonly used in various food preparations are known to possess antimicrobial activity against a wide spectrum of bacteria. Aim: The present study was performed to assess the in vitro effects of eugenol and cinnamaldehyde against indigenous and standard H. pylori strains, their minimum inhibitory concentrations (MICs) and time course lethal effects at various pH. Methods: A total of 31 strains (29 indigenous and one standard strain of H. pylori ATCC 26695, one strain of E. coli NCIM 2089) were screened. Agar dilution method was used for the determination of drug sensitivity patterns of isolates to the commonly used antibiotics and broth dilution method for the test compounds. Results: Eugenol and cinnamaldehyde inhibited the growth of all the 30 H. pylori strains tested, at a concentration of 2 μg/ml, in the 9th and 12th hours of incubation respectively. At acidic pH, increased activity was observed for both the compounds. Furthermore, the organism did not develop any resistance towards these compounds even after 10 passages grown at sub-inhibitory concentrations. Conclusion: These results indicate that the two bioactive compounds we tested may prevent H. pylori growth in vitro, without acquiring any resistance.

1 December 2003 in International Journal of Food Microbiology
Verified
Journal Article
Closed access
LML. Mannu
L. Mannu
APA. Paba
A. Paba
EDE. Daga
E. Daga
RCRoberta Comunian
Roberta Comunian
SZS. Zanetti
S. Zanetti
Leonardo SechiLeonardo Sechi
Leonardo Sechi

1 July 2005 in American Journal of Gastroenterology
Verified
Journal Article
Closed access
PDF file
Leonardo SechiLeonardo Sechi
Leonardo Sechi
Antonio Mario ScanuAntonio Mario Scanu
Antonio Mario Scanu
PMPaola Molicotti
Paola Molicotti
SCSara Cannas
Sara Cannas
MMManuela Mura
Manuela Mura
SZStefania Zanetti
Stefania Zanetti
Sardinia is an island community of 1.6 million people. There are also about 3.5 million sheep and one hundred thousand cattle in which Johne's disease and Mycobacterium avium subspecies paratuberculosis infection are endemic. The present study was designed to determine what proportion of people in Sardinia attending for ileocolonoscopy with or without Crohn's disease were infected with this pathogen. Mycobacterium avium subspecies paratuberculosis was detected by IS900 PCR on DNA extracts of fresh intestinal mucosal biopsies as well as by isolation in culture using supplemented MGIT media followed by PCR with amplicon sequencing. Twenty five patients (83.3%) with Crohn's disease and 3 control patients (10.3%) were IS900 PCR positive (p = 0.000001; Odds ratio 43.3). Mycobacterium avium subspecies paratuberculosis grew in cultures from 19 Crohn's patients (63.3%) and from 3 control patients (10.3%) (p = 0.00001; Odds ratio 14.9). All patients positive by culture had previously been positive by PCR. Mycobacterium avium subspecies paratuberculosis first appeared in the liquid cultures in a Ziehl Neelsen (ZN) staining negative form and partially reverted through a rhodamine-auramine positive staining form to the classical ZN positive form. This resulted in a stable mixed culture of all 3 forms illustrating the phenotypic versatility of these complex chronic enteric pathogens. Mycobacterium avium subspecies paratuberculosis was detected in the majority of Sardinian Crohn's disease patients. The finding of the organism colonizing a proportion of people without Crohn's disease is consistent with what occurs in other conditions caused by a primary bacterial pathogen in susceptible hosts.

19 February 2019 in Frontiers in Neurology
Verified
Journal Article
Open access
PDF file
ECElisa Caggiu
Elisa Caggiu
GAGiannina Arru
Giannina Arru
Sepideh HosseiniporghamSepideh Hosseiniporgham
Sepideh Hosseiniporgham
MNMagdalena Niegowska
Magdalena Niegowska
GSGianPietro Sechi
GianPietro Sechi
Leonardo SechiLeonardo Sechi
Leonardo Sechi
Parkinson's disease is a neurodegenerative disorder characterized by progressive loss of dopaminergic neurons of the substantia nigra pars compacta with a reduction of dopamine concentration in the striatum. The complex interaction between genetic and environmental factors seems to play a role in determining susceptibility to PD and may explain the heterogeneity observed in clinical presentations. The exact etiology is not yet clear, but different possible causes have been identified. Inflammation has been increasingly studied as part of the pathophysiology of neurodegenerative diseases, corroborating the hypothesis that the immune system may be the nexus between environmental and genetic factors, and the abnormal immune function can lead to disease. In this review we report the different aspects of inflammation and immune system in Parkinson's disease, with particular interest in the possible role played by immune dysfunctions in PD, with focus on autoimmunity and processes involving infectious agents as a trigger and alpha-synuclein protein (α-syn).

1 July 2009 in American Journal of Respiratory and Critical Care Medicine
Verified
Journal Article
Closed access
RZRichard N. van Zyl-Smit
Richard N. van Zyl-Smit
MPMadhukar Pai
Madhukar Pai
KPKwaku Peprah
Kwaku Peprah
RMRichard Meldau
Richard Meldau
JKJackie Kieck
Jackie Kieck
KDKeertan Dheda
Keertan Dheda
Conclusions: When using a two-step screening strategy it appears safe to perform a QuantiFERON-TB-GIT or T-SPOT.TB IGRA within 3 days of performing the TST. A 3-spot or 80% IFN-γ response variation, on either side of baseline values, explains 95% of the short-term variability and may be useful for interpreting conversions and reversions, and values close to the cut-point. Rationale: The optimal strategy for the diagnosis of latent tuberculosis infection is controversial. Adoption of a two-step strategy (tuberculin skin test [TST] followed by an IFN-γ release assay [IGRA], compared with an IGRA alone), may be limited by TST-mediated boosting of subsequent IGRA responses. Assessment of within-subject IGRA variability will aid in establishing thresholds for conversions and reversions, and interpretation of serial testing results. Objectives: To determine short-term IGRA variability and the impact of TST on subsequent IGRA results. Methods: Within-subject variability and TST-mediated boosting of IGRA responses were evaluated in 26 South African participants with varying exposure risk. IGRAs (T-SPOT.TB, QuantiFERON-TB Gold In-Tube [QuantiFERON-TB-GIT], PPD, and heparin-binding hemagglutinin) were repeated four times over 21 days pre-TST, and on Days 3, 7, 28, and 84 post-TST administration. Measurements and Main Results: All participants showed within-subject IGRA variability. Changes of ±3 spots (T-SPOT.TB) or ±80% from the mean IFN-γ response (QuantiFERON-TB-GIT) over 3 weeks explained 95% of the variability. Spontaneous conversions/reversions occurred in 7 of 26 subjects (27%) (6 for T-SPOT.TB and 1 for QuantiFERON-TB-GIT [P = 0.049]) during the within-patient variability studies (pre-TST). After the TST eight subjects (33%) boosted above the defined baseline variability. By Day 7 post-TST, but not Day 3, 2 (12.5%) initially IGRA-negative test subjects converted. By contrast, boosting of PPD and heparin-binding hemagglutinin occurred by Day 3 post-TST.

5 February 2001 in Journal of Applied Microbiology
Verified
Journal Article
Open access
PDF file
Leonardo SechiLeonardo Sechi
Leonardo Sechi
ILI. Lezcano
I. Lezcano
NNN. Nunez
N. Nunez
MEM. Espim
M. Espim
IDI. Dupre
I. Dupre
SZS. Zanetti
S. Zanetti
L.A. SECHI, I. LEZCANO, N. NUNEZ, M. ESPIM, I. DUPRÈ, A. PINNA, P. MOLICOTTI, G. FADDA AND S. ZANETTI. 2001. Aims: To evaluate the antimicrobial effect of the ozonized sunflower oil (Oleozon) on di...