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M Sanguinetti

Publications and source records attributed to M Sanguinetti.

At least 19 recordsLinked to original sources
PubMed2006

In vitro activity of Citrus bergamia (bergamot) oil against clinical isolates of dermatophytes.

OBJECTIVES: Recently, bergamot oil was shown to be a potent antifungal agent in vitro against clinically important Candida species. In this study, the activities of bergamot natural essence and its furocoumarin-free and distilled extracts on dermatophytes such as Trichophyton, Microsporum and Epidermophyton species were investigated. METHODS: In vitro susceptibility testing assays on 92 clinical isolates of dermatophytes (Trichophyton mentagrophytes n = 20, Trichophyton rubrum n = 18, Trichophyton interdigitale n = 15, Trichophyton tonsurans n = 2, Microsporum canis n = 24, Microsporum gypseum n = 1 and Epidermophyton floccosum n = 12) were performed using the CLSI M38-A broth microdilution method, except for employing an inoculum of 1-3 x 10(3) cfu/mL. MICs were determined at a visual endpoint reading of 80% inhibition compared with the growth control. RESULTS: MICs (v/v) of all fungi ranged from 0.156% to 2.5% for the natural essence, from 0.02% to 2.5% for the distilled extract, and from 0.08% to 1.25% for the furocoumarin-free extract. The three isolates of T. tonsurans and M. gypseum exhibited the highest MIC values. CONCLUSIONS: Data from this study indicate that bergamot oil is active in vitro against several common species of dermatophytes, suggesting its potential use for topical treatment of dermatophytoses.

Antifungal Agents↗
PubMed2006

Low-molecular weight heparin induces in vitro trophoblast invasiveness: role of matrix metalloproteinases and tissue inhibitors.

Heparin is used widely for the prevention of pregnancy loss in pregnant women with thrombophilia. However, it is still unknown if heparin may be able to affect trophoblast functions. Therefore, we investigated the hypothesis that low-molecular weight heparin (LMWH) might regulate in vitro trophoblast invasiveness and placental production of matrix metalloproteinases (MMPs) and tissue inhibitors (TIMPs). In the first-trimester placental tissue, the MMP-9 expression was observed in both villous and extravillous cytotrophoblast cells, and MMP-2 mainly in villous cytotrophoblast. In human choriocarcinoma cells (JAR), MMP-2 was the dominant form. Heparin significantly enhanced both pro-MMPs and the active forms, and increased Matrigel invasiveness of extravillous trophoblast and choriocarcinoma cells. In choriocarcinoma cells the heparin effect was also indirect, inducing a significant decrease in TIMP-1 and TIMP-2 protein expressions and mRNAs. The present data suggest that the increase in trophoblast invasion by heparin is due to a specific protein playing a role in placental invasion. These observations may help in understanding the effects of heparin treatment during pregnancy.

Anticoagulants↗
PubMed2004

In vitro activity of bergamot natural essence and furocoumarin-free and distilled extracts, and their associations with boric acid, against clinical yeast isolates.

OBJECTIVES: There is very little information, to date, on the antifungal activity of bergamot oil. In this study, we investigated the in vitro activity of three bergamot oils (natural essence, furocoumarin-free extract and distilled extract) against clinically relevant Candida species. We studied the two derivatives, components of Italian pharmaceutical products, that are supposed to be less toxic than the essential oil. METHODS: In vitro susceptibility of 40 clinical isolates of Candida spp. (Candida albicans, n=20; Candida glabrata, n=13; Candida krusei, n=4; Candida tropicalis, n=2; Candida parapsilosis, n=1), associated with symptomatic and asymptomatic vulvovaginal candidiasis, was determined using a modification of the NCCLS M27-A2 broth microdilution method. MICs were evaluated for each of the oils alone and combined with sub-inhibitory concentrations of the well-known antiseptic, boric acid. To boric acid, all isolates had MIC values ranging from 0.094% to 0.187% (w/v). RESULTS: At 24 h readings, the MIC(90 )s (for all isolates) were (v/v): 5% for natural essence of bergamot, 2.5% for the furocoumarin-free extract, and 1.25% for the distilled extract. At the 48 h reading, these values increased to >10%, 5% and 2.5%, respectively. At both readings, MIC(90 )s for all oil+boric acid combinations were significantly lower than corresponding values for the oils alone (P <0.05). CONCLUSIONS: These data indicate that bergamot oils are active in vitro against Candida spp., suggesting their potential role for the topical treatment of Candida infections.

Antifungal Agents↗
PubMed2001

Molecular basis of rifampin and isoniazid resistance in Mycobacterium bovis strains isolated in Sardinia, Italy.

Fourteen of 22 (68%) Mycobacterium bovis strains isolated from cattle in Sardinia were found to be resistant to rifampin and isoniazid. Analysis of the rpoB and the katG, oxyR-ahpC, and inhA gene regions of these strains was performed in order to investigate the molecular basis of rifampin and isoniazid resistance, respectively. The most frequent mutation, encountered in 6 of 10 strains (60%), was in the rpoB gene; it occurred, at codon position 521 and resulted in leucine changed to proline. This suggests that codon 521 may be important for the development of rifampin resistance in M. bovis. Resistance to isoniazid is associated in Mycobacterium tuberculosis with a variety of mutations affecting one or more genes. Our results confirm the difficulty of interpreting the sequence variations observed in clinical strains of M. bovis. M. bovis strains isolated from the same geographic area showed similar mutations within the genes responsible for rifampin and isoniazid resistance. Our results represent the first study to elucidate the molecular genetic basis of drug resistance in M. bovis isolated from cattle.

Animals↗
PubMed2001

Evaluation of BACTEC Mycobacteria Growth Indicator Tube (MGIT 960) automated system for drug susceptibility testing of Mycobacterium tuberculosis.

The reliability of the BACTEC MGIT 960 system, an automated version of the Mycobacteria Growth Indicator Tube (MGIT), for antimicrobial susceptibility testing of Mycobacterium tuberculosis was evaluated on 78 clinical isolates. Rifampin (RMP), isoniazid (INH), streptomycin (SM), and ethambutol (EMB) were tested at the following concentrations: 1.0 microg/ml for RMP, 0.1 and 0.4 microg/ml for INH, 1.0 and 4.0 microg/ml for SM, and 5.0 and 7.5 microg/ml for EMB. Results were compared with those obtained by the BACTEC 460 TB radiometric system. Initially the reproducibility study showed 99.5% agreement on repeat testing with all the four drugs. With susceptibility testing of clinical isolates, excellent agreement between the two systems was found for all the drugs. A total of nine major errors were observed for only three isolates, resistant according to BACTEC MGIT 960 and susceptible according to BACTEC 460 TB, to SM (4.0 microg/ml), INH (0.1 microg/ml), and EMB (5.0 microg/ml) (one isolate) and to SM (1.0 microg/ml), INH (0.4 microg/ml), and EMB (5.0 microg/ml) (two isolates). When these isolates were tested by using the conventional proportion method on Löwenstein-Jensen medium, agreement with BACTEC MGIT 960 was found for five results and with BACTEC 460 TB for the remainder. The time to report results was 7.9 days by MGIT 960 and 7.3 days by BACTEC 460 TB, which was not found statistically significant (P > 0.05). In conclusion, the performance of BACTEC MGIT 960 was found similar to that of BACTEC 460 TB and this new system can be considered a good alternative to the radiometric method for routine susceptibility testing of M. tuberculosis.

Antitubercular Agents↗
PubMed2001

Fatal pulmonary infection due to multidrug-resistant Mycobacterium abscessus in a patient with cystic fibrosis.

We report a case of fatal pulmonary infection caused by Mycobacterium abscessus in a young patient with cystic fibrosis, who underwent bipulmonary transplantation after a 1-year history of severe lung disease. Fifteen days after surgery he developed septic fever with progressive deterioration in lung function. M. abscessus, initially isolated from a pleural fluid specimen, was then recovered from repeated blood samples, suggesting a disseminated nature of the mycobacterial disease. Drug susceptibility testing assay, performed on two sequential isolates of the microorganism, showed a pattern of multidrug resistance. Despite aggressive therapy with several antimycobacterial drugs, including clarithromycin, the infection persisted, and the patient died.

Adult↗
PubMed2001

Molecular analysis of Klebsiella pneumoniae strains isolated in pediatric wards by ribotyping, pulsed field gel electrophoresis and antimicrobial susceptibilities.

The purpose of this study was to investigate the usefulness of different molecular typing techniques in the surveillance and control of the spread of extended-spectrum-beta-lactamase-(ESBL) producing Klebsiella pneumoniae in the pediatric department of the "Agostino Gemelli" hospital of the Catholic University in Rome, over a period of nine months. The strains were characterized by ribotyping using HindIII as restriction enzyme and pulsed field gel electrophoresis (PFGE) using XbaI as endonuclease. Sixty six K. pneumoniae clinical strains were isolated during this period, the first 32 were isolated in the summer of 1998. Among these first isolates, ribotyping generated 26 different patterns whereas PFGE produced 16 patterns. The remaining 34 strains were isolated during January and April 1999 and all of them were ESBL producers. Ribotyping clustered the strains into 6 patterns whereas PFGE generated only 3 patterns. PCR revealed the presence in 10 isolates of both bla(TEM) and bla(SHV) genes and 24 strains carried only the bla(SHV) gene. In our experience ribotyping revealed a higher power of differentiation with respect to PFGE and was of great help in the surveillance of the infection.

Cross Infection↗
PubMed2000

Commercial systems for fluconazole susceptibility testing of yeasts: comparison with the broth microdilution method.

Fluconazole susceptibility was tested in 100 clinical yeast isolates (65 Candida albicans, 13 C. glabrata, 8 C. tropicalis, 7 C. parapsilosis, 3 Saccharomyces cerevisiae, 1 each of C. krusei, C. lusitaniae, Cryptococcus neoformans, Rhodotorula glutinis) and two control strains (Candida krusei ATCC 6258, C. parapsilosis ATCC 22019) using broth microdilution (reference method), disk diffusion, Etest strips, Sensititre YeastOne, Candifast, Integral System Yeasts. Using M27-A breakpoints, isolates were classified as susceptible (81%), susceptible-dose dependent or Resistant with broth dilution. Rates of concordance with the reference method were good for Sensititre YeastOne, Etest and disc-diffusion (81.2%-94.7%) but very low for the Candifast (3.1%) and Integral System (16.6%), which classified most susceptible isolates as resistant. Lack of standardisation (inoculum, medium composition) and non-objective interpretation schemes may be the cause of their poor performance. Sensititre YeastOne, Etest and disc-diffusion are potentially useful for fluconazole antifungal susceptibility testing of yeasts in clinical laboratories.

Antifungal Agents↗
PubMed2000

Brief report: disseminated mycobacteriosis caused by drug-resistant Mycobacterium triplex in a human immunodeficiency virus-infected patient during highly active antiretroviral therapy.

Mycobacterium triplex is a novel species that, until now, has been isolated only from limited clinical samples, and its clinical relevance has been largely unknown. In this report, we describe the first case of disseminated disease caused by M. triplex in a human immunodeficiency virus-infected patient.

AIDS-Related Opportunistic Infections↗
PubMed2000

Reverse cross blot hybridization assay for rapid detection of PCR-amplified DNA from candida species, Cryptococcus neoformans, and Saccharomyces cerevisiae in clinical samples.

A PCR-based assay was developed to detect and identify medically important yeasts in clinical samples. Using a previously described set of primers (G. Morace et al., J. Clin. Microbiol. 35:667-672, 1997), we amplified a fragment of the ERG11 gene for cytochrome P-450 lanosterol 14alpha-demethylase, a crucial enzyme in the biosynthesis of ergosterol. The PCR product was analyzed in a reverse cross blot hybridization assay with species-specific probes directed to a target region of the ERG11 gene of Candida albicans (pCal), C. guilliermondii (pGui), C. (Torulopsis) glabrata (pGla), C. kefyr (pKef), C. krusei (pKru), C. parapsilosis (pPar), C. tropicalis (pTro), the newly described species C. dubliniensis (pDub), Saccharomyces cerevisiae (pSce), and Cryptococcus neoformans (pCry). The PCR-reverse cross blot hybridization assay correctly identified multiple isolates of each species tested. No cross-hybridization was detected with any other fungal, bacteria, or human DNAs tested. The method was tested against conventional identification on 140 different clinical samples, including blood and cerebrospinal fluid, from patients with suspected fungal infections. The results agreed with those of culture and phenotyping for all but six specimens (two of which grew yeasts not included in the PCR panel of probes and four in which PCR positivity-culture negativity was justified by clinical findings). Species identification time was reduced from a mean of 4 days with conventional identification to 7 h with the molecular method. The PCR-reverse cross blot hybridization assay is a rapid method for the direct detection and identification of yeasts in clinical samples.

Candida↗
PubMed2000

Comparison of the mycobacteria growth indicator tube with radiometric and solid culture for isolation of mycobacteria from clinical specimens and susceptibility testing of Mycobacterium tuberculosis.

We compared the mycobacteria growth indicator tube (MGIT) system with the BACTEC 460 TB and Loewenstein-Jensen (LJ) systems for the recovery of mycobacteria (acid-fast bacilli [AFB]) from 600 clinical specimens. A total of 50 AFB (32 Mycobacterium tuberculosis complex, 10 M. avium complex, 3 M. gordonae, 3 M. xenopi, 1 M. terrae and 1 M. fortuitum) were detected. MGIT recovered 50 isolates of AFB (100% sensitivity), and BACTEC 460 TB and LJ recovered 49 (98% sensitivity) and 19 (38% sensitivity) AFB isolates, respectively. The mean times to detect mycobacteria were 10, 10 and 25 days for MGIT, BACTEC 460, and LJ slants. All isolates of M. tuberculosis complex were tested for susceptibility to streptomycin, isoniazid, rifampin, and ethambutol with the MGIT and BACTEC 460 TB. Both systems yielded identical susceptibility data with different mean times to report (5.38 days for MGIT versus 7.33 days for BACTEC 460 TB, P<0.05). The results suggest that MGIT is equivalent to BACTEC 460 TB in its ability to support the growth of mycobacteria, but significantly more efficient than LJ. MGIT may also be used for susceptibility testing of primary antituberculosis drugs.

Anti-Bacterial Agents↗
PubMed1999

Simple and rapid identification of different species of Mycobacteria by PCR.

A simple polymerase chain reaction (PCR) assay for rapid identification of different species of mycobacteria was developed. This PCR is based on the use of conserved sequences to amplify the genome of several mycobacterial species. The amplification patterns obtained were specific and reproducible for the species tested. In particular, we could identify Mycobacterium tuberculosis and Mycobacterium bovis (both produced the same pattern), Mycobacterium avium, Mycobacterium kansasii, Mycobacterium xenopi, Mycobacterium chelonae, Mycobacterium peregrinum, Mycobacterium fortuitum, Mycobacterium gordonae and Mycobacterium smegmatis. Moreover, due to the numerous copies of the target sequences present in the genome, the PCR showed a very high level of sensitivity.

AIDS-Related Opportunistic Infections↗
PubMed1999

Application of molecular methods for detection and transmission analysis of mycobacterium tuberculosis drug resistance in patients attending a reference hospital in Italy.

A molecular analysis of drug-resistant isolates of Mycobacterium tuberculosis was done in a population with a high prevalence of human immunodeficiency virus infection. Seventy-one consecutive isolates were tested for genotypic resistance to isoniazid, rifampicin, streptomycin, and ethambutol by polymerase chain reaction-single strand conformation polymorphism analysis and automated sequencing of target regions. Phenotypic and genotypic resistance to isoniazid, rifampicin, streptomycin, and ethambutol were detected in 23.4%, 11.2%, 7%, and 5.6% of isolates and in 87%, 88%, 40%, and 100% of resistant isolates, respectively. Specificity was 100% for all target regions. When rpoB, katG, and ahpC mutation analysis were combined, 86% of resistant isolates to any drug were identified. No mutations in inhA were found in isoniazid-resistant isolates. Molecular detection of drug resistance, particularly for isoniazid and rifampicin, may represent a sensitive and very specific technique. The strategy of selecting rpoB, katG, and ahpC to quickly identify most resistant isolates, with a relevant saving of resources, is warranted.

Drug Resistance, Microbial↗
PubMed1999

Retrospective study of candidemia in patients with hematological malignancies. Clinical features, risk factors and outcome of 76 episodes.

A retrospective study of 76 episodes of candidemia in 73 patients with underlying hematological malignancy, from 1988 until 1997, has been conducted to evaluate the clinical characteristics and to ascertain the variables related to the onset and the outcome of candidemia. The most frequent malignancy was acute myeloid leukemia (29 episodes). Candidemia developed mainly during aplasia in patients refractory to chemotherapy (42%). In 65 episodes (86%) the patients were neutropenic (ANC <1 x 10(9)/l) before the candidemia diagnosis for a median time of 13 d, and in 53 episodes (70%) at microbiological diagnosis of candidemia ANC was <1 x 10(9)/l. Candida albicans was the most frequently isolated etiologic agent (31 episodes), but C. non-albicans species sustained the majority of candidemia. Seventeen candidemias developed during azoles prophylaxis. One month after the diagnosis of candidemia, 26 patients died. In 19 cases, death was attributable to candidemia. The case-control study demonstrated, at univariate analysis, that the colonization with Candida. spp. (p=0.004), antimycotic prophylaxis (p=0.01), presence of central venous catheter (p=0.01), neutropenia (p=0.002), and the use of glycopeptide (p=0.0001) increased the risk of candidemia. Using multivariate regression analysis only colonization with Candida spp. and the previous therapy with glycopeptide were associated with a significantly increased risk. Acute mortality, expressed by a cumulative probability of survival at 30 d from diagnosis of candidemia, was 0.67 (95% C.I. 0.55-0.77) and was significantly reduced in patients with neutrophils <1 x 10(9)/l when compared to those with neutrophils >1 x 10(9)/l (p at Mantel-Cox=0.029). Overall cumulative probability of survival at 1 yr was 0.38 (95% C.I. 0.27-0.49) and only the treatment with Amfotericin B significantly reduced the risk of death.

Adolescent↗
PubMed1999

Differentiation of Vibrio alginolyticus strains isolated from Sardinian waters by ribotyping and a new rapid PCR fingerprinting method.

We investigated the usefulness of a novel PCR fingerprinting technique, based on the specific amplification of genomic regions, to differentiate 30 Vibrio alginolyticus strains isolated in Sardinian waters. The different profiles obtained were scanned and analyzed by a computer program in order to determine genetic relationships. The results were then compared with the patterns obtained by ribotyping with HindIII, KpnI, and XbaI restriction enzymes. PCR fingerprinting could differentiate the strains analyzed into 12 different patterns, whereas ribotyping with XbaI, which produced the highest number of patterns, generated only 7 different profiles. This study revealed the superior discriminative power of the proposed technique for the differentiation of related V. alginolyticus strains and the potential use of PCR fingerprinting in epidemiological studies.

Bacterial Typing Techniques↗
PubMed1999

PCR-restriction enzyme analysis for detection of Candida DNA in blood from febrile patients with hematological malignancies.

Blood samples were drawn daily from 72 patients who had hematological malignancies, neutropenia, and fever and who had failed to respond to broad-spectrum antibiotics. Each sample was used for conventional fungal blood cultures and for detection and identification of Candida DNA by a PCR method with subsequent restriction enzyme analysis (REA) recently developed in our laboratory. The PCR method was able to detect five CFU of Candida spp. per ml of blood, and subsequent REA of the amplicons allowed the identification of the Candida species most commonly implicated in cases of candidiasis. Thirty-one patients were PCR-REA positive, and four of these patients were also culture positive. The ultimate diagnosis for 13 of these patients and 1 patient who was PCR-REA negative was disseminated candidiasis (confirmed by clinical data, multiple cultures, histology, autopsy, and/or ultrasonographic evidence of hepatosplenic candidiasis). The molecular method is significantly more sensitive than conventional fungal blood cultures and has a high negative predictive value (97.5%) for the development of disseminated candidiasis in neutropenic patients.

Amphotericin B↗