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Streptococcus salivarius 24SMB administered by nasal spray for the prevention of acute otitis media in otitis-prone children. Eur J Clin Microbiol Infect Dis 2015; 34:2377-83. [PMID: 26385346 DOI: 10.1007/s10096-015-2491-x] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 09/09/2015] [Indexed: 11/24/2022]
Abstract
This paper reports the results of the first study in which Streptococcus salivarius 24SMB, a safe α-haemolytic strain capable of producing bacteriocin-like substances with significant activity against acute otitis media (AOM) pathogens, was intranasally administered in an attempt to reduce the risk of new episodes of AOM in otitis-prone children. In this prospective, randomized, double-blind, placebo-controlled study, 100 children aged 1-5 years with histories of recurrent AOM were randomized 1:1 to receive an intranasal S. salivarius 24SMB or placebo twice daily for 5 days each month for 3 consecutive months. Fifty treated children and 47 who received placebo who were compliant with study protocol were followed monthly for 6 months. The number of children who did not experience any AOM was higher among the children treated with the S. salivarius 24SMB preparation than among those in the placebo group (30.0 vs 14.9%; p = 0.076). Moreover, the number of children who received antibiotics during the study period was lower among the children treated with S. salivarius 24 SMB than among those who received placebo (70 vs 83.0%; p = 0.13). Compared with the children who were not colonized by S. salivarius 24SMB after treatment, the number of colonized children who experienced any AOM was significantly lower (42.8 vs 13.6%; p = 0.03). Similar results were observed when the children treated with antibiotics for AOM were analysed (67.8 vs 95.5%; p = 0.029). This study revealed the ability of intranasally administered S. salivarius 24SMB to reduce the risk of AOM in otitis-prone children.
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Colonization, safety, and tolerability study of the Streptococcus salivarius 24SMBc nasal spray for its application in upper respiratory tract infections. Eur J Clin Microbiol Infect Dis 2015. [PMID: 26205666 DOI: 10.1007/s10096-015-2454-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Streptococcus salivarius, a non-pathogenic species and the predominant colonizer of the oral microbiota, finds a wide application in the prevention of upper respiratory tract infections, also reducing the frequency of their main pathogens. In this pilot study, the primary objective was to evaluate the safety and tolerability of a nasal spray, S. salivarius 24SMBc, as a medical device in a clinical study involving 20 healthy adult subjects. The secondary aim was to determine the ability of colonization assessed by molecular fingerprinting. Twenty healthy adult subjects, aged between 30 and 54 years, without a medical history of recurrent otitis media, were enrolled. All patient characteristics fulfilled the inclusion criteria. All subjects were treated daily for 3 days with the nasal spray containing S. salivarius 24SMBc at a concentration of 5 × 10(9) colony-forming units (CFU)/ml. The persistence of S. salivarius in the nasopharynx was investigated by the antagonism test and random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR). The tolerability and safety were clinically assessed by clinical examinations during treatment. Our results demonstrate the capability of S. salivarius 24SMBc to colonize the rhinopharynx tissues in 95% of subjects and persist in 55% of them after 6 days from the last dose of the formulation, maintaining a concentration of 10(5) CFU/ml. The treatment was well tolerated by all healthy patients and no adverse effects were found. The topical application of streptococcal probiotics is a relatively undeveloped field but is becoming an attractive approach for both prevention and therapy, especially for pediatric age patients. S. salivarius 24SMBc possess characteristics making this strain suitable for use in bacteriotherapy.
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Activity of Telithromycin Against Multi-Drug ResistantStreptococcus pneumoniaeand Molecular Characterization of Macrolide and Tetracycline Resistance Determinants. J Chemother 2013; 17:502-8. [PMID: 16323438 DOI: 10.1179/joc.2005.17.5.502] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
The antistreptococcal activity of telithromycin and 11 different comparators was evaluated in 26 multi-drug resistant (MDR) Streptococcus pneumoniae strains collected during 2002-2003 as part of the ongoing PROTEKT (Prospective Resistant Organism Tracking and Epidemiology for the Ketolide Telithromycin) Italian Surveillance Program. The strains were characterized for their susceptibility to antibiotics both at the phenotypic and genotypic levels; furthermore, the association of erm(B), mef(A) class and tet(M) genes, as well as the mobile elements carrying them were determined. The strains in this study were resistant to penicillin (MIC > or = 2 mg/l) in 23.1% of cases, resistant to tetracycline in 88.4%, to cotrimoxazole in 34.6% and cefuroxime in 26.9% while only telithromycin and levofloxacin retained 100% activity against all microorganisms. Co-existence of different resistance determinants was found in 19.2% of all isolates collected in our laboratory, coming from southern Italy. Twenty-three isolates showing the MLSB phenotype of resistance possessing the erm(B) gene (88.5%), associated with tet(M), were carried on the same Tn1545-like element, while two isolates showing the M phenotype possessing the mef(A) gene alone, were carried on Tn1207.1. In only one strain were mef(E) and tet(M) together carried on Tn2009.
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Emergence of an extensively drug-resistant ArmA- and KPC-2-producing ST101 Klebsiella pneumoniae clone in Italy. J Antimicrob Chemother 2013; 68:1932-4. [DOI: 10.1093/jac/dkt116] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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DNA methylase modifications and other linezolid resistance mutations in coagulase-negative staphylococci in Italy. J Antimicrob Chemother 2010; 65:2336-40. [DOI: 10.1093/jac/dkq344] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Presence of the ica operon in clinical isolates of Staphylococcus epidermidis and its role in biofilm production. Clin Microbiol Infect 2004; 10:1081-8. [PMID: 15606635 DOI: 10.1111/j.1469-0691.2004.01024.x] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Staphylococcus epidermidis is an important cause of catheter-associated infections, which are attributed to its ability to form a multilayered biofilm on polymeric surfaces. This ability depends, in part, on the activity of the icaADBC locus and the icaR gene, which are involved in the production of the polysaccharide intercellular adhesin (PIA) that is functionally necessary for cell-to-cell adhesion and biofilm accumulation. The present study determined: (1) the prevalence of the icaADBC operon in S. epidermidis isolates from catheter-related and other nosocomial infections; (2) the correlation between the presence of this operon, biofilm production and resistance to antibiotics; (3) the expression of ica genes and biofilm production; and (4) the genetic relatedness of the isolates. The results showed that icaRADBC was present in 45% of the isolates included in the study, and that such isolates were significantly more resistant to the main antibiotics tested than were ica-negative isolates. The presence of the entire cluster did not always correlate with biofilm production, determined under different culture conditions, but there was evidence to suggest a correlation when at least two genes (icaAD) were co-transcribed. Eight of 18 ica-positive isolates had the entire operon in the same restriction fragment after pulsed-field gel electrophoresis, but the isolates were not clonal. Estimation of genetic relatedness indicated that ica-positive S. epidermidis isolates belonged to different lineages, distributed in only one of two major clusters, with a genetic distance of c. 0.12.
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Clonal types and multidrug resistance patterns of methicillin-resistant Staphylococcus aureus (MRSA) recovered in Italy during the 1990s. Microb Drug Resist 2004; 10:106-13. [PMID: 15256025 DOI: 10.1089/1076629041310109] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
A large number (272) of methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered from Italian hospitals during the early and late 1990s were characterized for multidrug resistance pattern and clonal type using a combination of genotyping methods, including pulsed-field gel electrophoresis (PFGE), spaA typing, multilocus sequence typing (MLST), determination of SCC mec type, and hybridization pattern with Tn 554. The majority of MRSA belonged to four genetic lineages: the pandemic Iberian and Brazilian clones, and two unique clonal types-the "Italian" and "Rome" clones of MRSA. The Italian clone carried the SCC mec type I in the genetic background of ST228, which is a double-locus variant of the sequence type of the multidrug-resistant New York/Japanese clone (ST5). The properties of the Rome clone showed several striking similarities to those of the Archaic clone of MRSA that was dominant among MRSA isolates in the mid-1960s to 1970s, but has not been detected since then in recent global surveillance studies.
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In vitro activity of levofloxacin against coagulase-positive and -negative staphylococci. DRUGS UNDER EXPERIMENTAL AND CLINICAL RESEARCH 2002; 27:107-11. [PMID: 11447768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
The in vitro activity of levofloxacin compared with that of ciprofloxacin, ofloxacin and norfloxacin were examined by conventional in vitro tests against 150 clinical isolates of staphylococci, subdivided according to species and susceptibility to methicillin. Although the minimum inhibitory concentrations (MICs) of all quinolones were highest in methicillin-resistant Staphylococcus aureus strains, the activity of levofloxacin was almost complete in methicillin-resistant S. epidermidis and methicillin-resistant S. haemolyticus when compared with ciprofloxacin and ofloxacin, which showed more than 30% resistance. Methicillin-susceptible S. aureus and S. epidermidis strains were susceptible to all quinolones with few differences between the antibiotics tested. The minimal bactericidal activity of levofloxacin was within the double dilution range of MIC values for all strains tested, demonstrating its potent role against staphylococci. In time-kill studies, levofloxacin exerted bactericidal activity within 3 h against all staphylococci. These in vitro results suggest that levofloxacin is a potent fluoroquinolone against coagulase-negative staphylococci and that it is both methicillin-susceptible and resistant. Further studies are necessary to determine the role of this drug in the treatment of infections sustained by these microorganisms.
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Macrolide efflux genes mef(A) and mef(E) are carried by different genetic elements in Streptococcus pneumoniae. J Clin Microbiol 2002; 40:774-8. [PMID: 11880392 PMCID: PMC120261 DOI: 10.1128/jcm.40.3.774-778.2002] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Susceptibilities to macrolides were evaluated in 267 Streptococcus pneumoniae isolates, of which 182 were from patients with invasive diseases and 85 were from healthy carriers. Of the 98 resistant isolates, 20 strains showed an M phenotype and carried mef. Strains that carried both mef(A) and mef(E) were found: 17 strains carried mef(A) and 3 carried mef(E). The characteristics of the strains carrying the mef genes and the properties of the mef-containing elements were studied. Strains carrying mef(A) belonged to serotype 14, were susceptible to all the antibiotics tested except erythromycin, and appeared to be clonally related by pulsed-field gel electrophoresis (PFGE). The three mef(E) strains belonged to different serotypes, showed different susceptibility profiles, and did not appear to be related by PFGE. The sequences of a fragment of the mef-containing element, which encompassed mef and the msr(A) homolog, were identical among the three mef(E)-positive strains and among the three mef(A)-positive strains, although there were differences between the sequences for the two variants at 168 positions. In all mef(A)-positive strains, the mef element was inserted in celB, which led to impairment of the competence of the strains. In line with insertion of the mef(E) element at a different site, the competence of the mef(E)-positive strains was maintained. Transfer of erythromycin resistance by conjugation was obtained from two of three mef(A) strains but from none of three mef(E) strains. Due to the important different characteristics of the strains carrying mef(A) or mef(E), we suggest that the distinction between the two genes be maintained.
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Rapid method for detection of gyrA and grlA mutations in unrelated strains of Staphylococci susceptible and resistant to levofloxacin. THE NEW MICROBIOLOGICA 2001; 24:347-53. [PMID: 11718372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
A panel of 150 clinical isolates of methicillin resistant and susceptible Staphylococci were investigated using a rapid and simple PCR-RFLPs technique to detect DNA nucleotide changes at the site of the most frequently reported mutations in grlA (codons 79, 80) and gyrA (codons 83, 84) genes which confer fluorquinolone resistance in Staphylococci. Convergent dual mutations in and gyrA and grlA were found in all strains exhibiting resistance to ciprofloxacin (MIC, 8 to > or =128 mg/l) and levofloxacin (MIC, 8 to > or =64 mg/l). Mutations in grlA and gyrA were also found in strains susceptible to levofloxacin and resistant to ciprofloxacin. In our sample no strains with only grlA mutations were found. Our data indicate that methicillin-resistant fluorquinolone-resistant strains are likely to have mutations in both grlA and gyrA. In contrast, methicillin-susceptible strains do not show any mutation. The genetic relatedness of a sample of representative epidemiologically unrelated MRSA strains, tested by PFGE and rep-PCR, are in agreement with the hypothesis of a clonal selection of these resistant strains.
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rrn operons in Haemophilus parainfluenzae and mosaicism of conserved and species-specific sequences in the 16S-23S rDNA long spacer. Res Microbiol 2001; 152:461-8. [PMID: 11446514 DOI: 10.1016/s0923-2508(01)01219-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The mosaic organisation of short-sequence boxes was analysed in the cloned and sequenced long ribosomal spacer (547 bp) of Haemophilus parainfluenzae GR. Comparison and alignment of both the long and the short spacer were performed in H. parainfluenzae and H. influenzae Rd. The long spacer contained two tRNA genes (tRNA(Ala) and tRNA(Ile)) which are highly homologous to the corresponding genes found in the spacers of other species, such as Haemophilus spp., Actinobacillus spp., and Plesiomonas shigelloides. At the 3' end of tRNA(Ala) a putative ribosomal spacer loop was found, showing a strong secondary structure. Pulsed field gel electrophoresis (PFGE) analysis after restriction of the genome of H. parainfluenzae GR with I-Ceu I and subsequent polymerase chain reaction (PCR) analysis of PFGE-separated DNA fragments demonstrated that the H. parainfluenzae genome contained six operons and that the long spacer was present in three copies of them. Two short DNA segments were identified as being species-specific, allowing us to design PCR primers which were useful in the molecular identification of H. parainfluenzae isolates.
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MESH Headings
- Base Sequence
- Blotting, Southern
- Cloning, Molecular
- Conserved Sequence
- DNA, Bacterial/genetics
- DNA, Ribosomal Spacer/genetics
- Electrophoresis, Gel, Pulsed-Field
- Haemophilus/classification
- Haemophilus/genetics
- Haemophilus/growth & development
- Haemophilus/isolation & purification
- Molecular Sequence Data
- Plasmids
- Polymerase Chain Reaction
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 23S/genetics
- RNA, Transfer/genetics
- RNA, Transfer, Glu/genetics
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
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[Correlation between methicillin-resistance and resistance to fluoroquinolones in Staphylococcus aureus and Staphylococcus epidermidis]. LE INFEZIONI IN MEDICINA 2001; 9:90-7. [PMID: 12698021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
Fluoroquinolones resistance in Staphylococci is associated to point mutations in grlA (80,84 and 116) grlB, gyrA (84,88) and gyrB genes. Almost all MRSA strains are ciprofloxacin and levofloxacin resistant while, in a lesser degree, MRCoN staphylococci show to be resistant to levofloxacin. This observation made possible to predict a different correlation between methicillin-resistance and the resistance to FQs in this two different species. In this study, we compare genomic analysis of S. aureus and S. epidermidis with the resistance to FQs. Our results show that strains of MRSA are distributed in 4 different PFGE-types while 12 MRSE strains are distributed in 9. MRSA resistant to FQs showed a unique PFGE pattern; on the contrary of FQs susceptible MRSA and MSSA. Furthermore mecA and gyrA genes are located in the same SmaI fragment in MRSA and in different in MRSE. MSSE and MRSE show more ClaI/mecA polymorphisms than MRSA. All this data confirm the clonal origin of MRSA and show that FQs resistance is linked to the presence of mec locus and both clonally spread. On the contrary in MRSE FQs-resistance is independent from MR and arise with the normal frequence of antibiotic induction.
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Abstract
This work reports the synthesis and the binding tests on the 5-HT3 and 5-HT4 receptors of new thienopyrimidopiperazine and piperazinylacylaminodimethylthiophene derivatives, in order to identify potent and selective ligands for each receptor. The 3-amino-2-(4-benzyl-1-piperazinyl)-5,6-dimethyl-thieno[2,3-d]pyrimidin-4(3H)-one derivative 28 showed the highest affinity and selectivity for the 5-HT3 over the 5-HT4 receptor (5-HT3 Ki=3.92 nM, 5-HT4 not active), whereas the 2-[4-[4-(2-pyrimidinyl)-1-piperazinyl]butanoylamino]-4,5-dimethyl-3-thiophenecarboxylic acid ethyl ester (41) showed the highest affinity and selectivity for the 5-HT4 over the 5-HT3 receptor (5-HT4 Ki=81.3 nM, 5-HT3 not active). Conformational analyses were carried out on the compounds of the piperazinylacylaminodimethylthiophene series (39-42) taking compound 41 as the template.
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Design, synthesis and binding properties of novel and selective 5-HT(3) and 5-HT(4) receptor ligands. Eur J Med Chem 2000; 35:1065-79. [PMID: 11248405 DOI: 10.1016/s0223-5234(00)01187-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This work reports the synthesis and the binding tests on the 5-HT(3) and 5-HT(4) receptors of new thienopyrimidopiperazine and piperazinylacylaminodimethylthiophene derivatives, in order to identify potent and selective ligands for each receptor. The compound with higher affinity and selectivity for the 5-HT(3) over the 5-HT(4) receptor was the 3-amino-2-(4-benzyl-1-piperazinyl)-5,6-dimethyl-thieno[2,3-d]pyrimidin-4(3H)-one 28 (5-HT(3) K(i)=3.92 nM, 5-HT(4) not active), the compound with higher affinity and selectivity for the 5-HT(4) over the 5-HT(3) receptor was the 2-[4-[4-(2-pyrimidinyl)-1-piperazinyl]butanoylamino]-4,5-dimethyl-3-thiophenecarboxylic acid ethyl ester 41 (5-HT(4) K(i)=81.3 nM, 5-HT(3) not active). Conformational analyses were carried out on the compounds of the piperazinylacylaminodimethylthiophene series (39-42) taking compound 41 as the template.
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Synthesis and pharmacological screening of 1,3,4-thiadiazino[2,3-b]quinazoline derivatives. DIE PHARMAZIE 2000; 55:737-40. [PMID: 11082833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Derivatives of 1,3,4-thiadiazino[2,3-b]quinazoline 7, 9, 9a, 12, 12a, and 13 were prepared from the 3-amino-6-bromo-2,3-dihydro-2-thioxo-4-(1H)-quinazolinone (2) and its analogue without bromine. A series of the title derivatives with or without bromine was tested and the results of pharmacological screening are discussed.
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Characterization of a genetic element carrying the macrolide efflux gene mef(A) in Streptococcus pneumoniae. Antimicrob Agents Chemother 2000; 44:2585-7. [PMID: 10952626 PMCID: PMC90116 DOI: 10.1128/aac.44.9.2585-2587.2000] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2000] [Accepted: 06/27/2000] [Indexed: 11/20/2022] Open
Abstract
The mef(A) gene from a clinical isolate of Streptococcus pneumoniae exhibiting the M-type resistance to macrolides was found to be part of the 7,244-bp chromosomal element Tn1207.1, which contained 8 open reading frames. orf2 encodes a resolvase/invertase, and orf5 is a homolog of the macrolide-streptogramin B resistance gene msr(SA).
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Synthesis of new [1,3,4]thiadiazolo[3,2-a]thieno[2,3-d]pyrimidinone derivatives with antiinflammatory activity. DIE PHARMAZIE 2000; 55:500-2. [PMID: 10944776 DOI: 10.1002/chin.200042143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
New thiadiazolothienopyrimidinones were synthesized in continuation of efforts to prepare thienopyrimidine derivatives with analgesic and antiinflammatory activities. In this study, the effect of various substituents in the thiophene ring on the pharmacological activity of the compounds was investigated.
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18
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High affinity and selectivity of [[(arylpiperazinyl)alkyl]thio]thieno[2,3-d]pyrimidinone derivatives for the 5-HT(1A) receptor. Synthesis and structure-affinity relationships. Eur J Med Chem 2000; 35:677-89. [PMID: 10960183 DOI: 10.1016/s0223-5234(00)00175-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In this work we report the affinity of new thienopyrimidinones for 5-HT(1A)Rs and the selectivity versus alpha(1)ARs. The 3-amino-2-[[3-[4-(2-methoxyphenyl)-1-piperazinyl]propyl]thio]-6-ethyl -thieno[2,3-d]pyrimidin-4(3H)-one 27 is the most potent and selective (Ki 0.19 nM, selectivity 115). Compound 31 with the N4 piperazine orthonitrophenyl nucleus instead of the orthomethoxyphenyl also shows a good affinity and selectivity (Ki 1. 46 nM, selectivity 84). The results of derivatives 28, 29 and 30 (Ki 3.28, 12.59 and 4.38 nM; selectivity 24, 4 and 5, respectively), which have, respectively, an ethyl, an allyl and an acetylamino group instead of an N3 amino group, indicate the importance of this last group for the interaction with 5-HT(1A)R. Comparison of the results for the superior homologue 53 (Ki 3.72 nM, selectivity 51) and the inferior homologue 52 (5-HT(1A) Ki 1499 nM, alpha(1)A Ki NA) of 2-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-6,7-dimethyl-8H-[1, 3,4]thiadiazolo[3,2-a]thieno[2,3-d]pyrimidin-8-one 57 (Ki 23 nM, selectivity 5) shows how important the length of the chain binding the two heterocyclic systems is in the interaction with 5-HT(1A)Rs and alpha(1)ARs.
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Abstract
This paper reports the synthesis and affinities on the 5-HT1A versus the alpha1A receptors of new arylpiperazinylalkylthiothienopyrimidine and thiadiazole derivatives 16-24. Arylpiperazines 16-23 show affinities values in the nanomolar range for the 5-HT1A receptor. The compound 16 is highly potent (Ki 0.26 nM, selectivity 28), the derivatives 20 and 21 are less potent, but highly selective (Ki 9.40 and 5.06 nM, selectivity 207 and 73, respectively).
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Molecular epidemiology of enterococci with high-level resistance to aminoglycosides. Microb Drug Resist 2000; 1:293-7. [PMID: 9158799 DOI: 10.1089/mdr.1995.1.293] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
DNA-based methodologies are considerably more powerful than other phenotype-based typing systems, providing a finer level of epidemiological discrimination, differentiating both closely and distantly related independent isolates that otherwise may appear as identical. In this study, plasmid analysis and pulsed-field gel electrophoresis were used to compare 28 isolates of Enterococci (respectively 13 strains of Enterococcus faecalis and 15 strains of Enterococcus faecium) with high-level resistance to aminoglycosides, isolated in Catania (Italy). Plasmid profile analysis resolved 20 different patterns among 24 plasmid harboring strains; many isolates showed one or two plasmids of the same size, but different plasmid content. Analysis of the PFGE-based RFLP patterns after SmaI digestion of genomic DNA resolved 26 different clones from 28 isolates: particularly, it resolved two different clones from three isolates showing identical plasmid profiles, and it identified as a single clone two isolates exhibiting different plasmid profiles. Thus, on the basis of our PFGE-based RFLP analysis data, we concluded that all the strains included in the study were genetically unrelated with two exceptions.
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Abstract
In order to study the possible phenotypic and genotypic changes related to glycopeptide pressure on enterococci, a study was undertaken using stepwise in vitro exposure to achieve the following objectives: (i) to evaluate the development of resistance and cross-resistance between vancomycin and teicoplanin; (ii) to determine the stability of the acquired level of resistance; (iii) to determine the phenotypic and genotypic changes related to glycopeptide pressure; and (iv) to assess the spectrum of antibiotic-susceptibility of all strains. Our results showed that no variants resistant to glycopeptides could be selected after in vitro glycopeptide exposure experiments. However some strains showed increased MIC values: 8 mg/l to vancomycin in eight strains selected by vancomycin itself, while teicoplanin produced intermediate values to vancomycin in only three strains. The phenotypes were stable in vitro after numerous passages in antibiotic-free medium and three out of nine strains with a changed MIC level, showed 40, 42 and 43 kDa proteins in cell membrane preparations. The profile of antibiotic resistance was comparable in all isogenic strains tested with the exception of three selected strains that became susceptible to penicillin G. The pressure produced by glycopeptides, particularly vancomycin has contributed to an increased level of MIC that can influence the acquisition and/or full expression of this resistance.
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Building a model of interaction at the NK-2 receptors: Polycondensed heterocycles containing the pyrimidoindole skeleton. Eur J Med Chem 1998. [DOI: 10.1016/s0223-5234(97)89641-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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In vitro activity of biapenem against recent gram-negative and gram-positive clinical isolates. Chemotherapy 1997; 43:393-3. [PMID: 9395852 DOI: 10.1159/000239597] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The in vitro activity of biapenem, a new carbapenem, against 535 clinical recent isolates was compared with those of other antibiotics. Biapenem showed broad-spectrum activity against gram-negative and gram-positive clinical isolates. The new carbapenem was more active than imipenem against members of the family Enterobacteriaceae with MIC90S ranging from 0.12 to 2 mg/l and from 0.25 to 4 mg/l, respectively. Moreover it was 2-fold more active than imipenem against Pseudomonas aeruginosa (MIC90, 8 and 16 mg/l, respectively). Taken together, these results indicate that biapenem shares the favorable in vitro activity properties of imipenem and merits further study in the treatment of infections caused by a wide range of pathogens.
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24
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[[(Arylpiperazinyl)alkyl]thio]thieno[2,3-d]pyrimidinone derivatives as high-affinity, selective 5-HT1A receptor ligands. J Med Chem 1997; 40:574-85. [PMID: 9046348 DOI: 10.1021/jm950866t] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A series of 2-[[(4-aryl-1-piperazinyl)alkyl]thio]thieno[2,3-d]pyrimidin-4 (1H)-one and 3-substituted 2-[[(4-aryl-1-piperazinyl)alky]thio]thieno[2,3-d]pyrimidin-4 (3H)-one derivatives was prepared and evaluated for in vitro 5-HT1A receptor affinity by radioligand binding assays; the selectivity for 5-HT1A receptors rather than alpha 1-adrenoceptors was also examined (ratio of the IC50 alpha 1 to IC50 5-HT1A). The binding tests gave indications about the best features of the [(arylpiperazinyl)alkyl]thio moiety and of the substituents on the thiophene and pyrimidinone rings for efficacious and selective 5-HT1A ligands. The most effective derivative for displacing [3H]-8-OH-DPAT from rat hippocampal membranes was the 3-amino-2-[[3-[4-(2-methoxyphenyl)-1-piperazinyl] propyl]thio]-5,6-dimethylthieno[2,3-d]pyrimidin-4(3H)-one (70) (IC50 = 0.3 nM) with selectivity of 24 for the 5-HT1A over the alpha 1-adrenoceptor. Compound 73, where the 2-methoxyphenyl on the N4 piperazine ring was replaced with a pyrimidine group, showed the best selectivity, with a ratio of 74, while its affinity IC50 for 5-HT1A was 6.8 nM. These results, compared to those for compounds 46 (IC50 24 nM; selectivity 2) and 49 (IC50 226 nM; selectivity 5), N3 unsubstituted analogues of derivatives 70 and 73, show the importance of an amino group in position 3 of the thienopyrimidine system for the interaction with 5-HT1A receptor binding sites, although this fragment can affect the affinity and selectivity only if linked to the (arylpiperazinyl)alkyl moiety. The better selectivity of piperidine 74 (IC50 0.8; selectivity 45) compared to the analogous piperazine 70 is also noteworthy. Twenty of the 30 molecules used for determining the binding affinity to 5-HT1A and alpha 1-adrenergic receptors were selected for QSAR analysis using a series of molecular descriptors and calculated with the TSAR software.
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25
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Synthesis of aminothienopyrimidine and thienotriazolopyrimidine derivatives as potential anticonvulsant agents. DIE PHARMAZIE 1996; 51:7-11. [PMID: 8999439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
New aminothienopyrimidines and derivatives of the new thienotriazolopyrimidine ring system were synthesized to investigate their anticonvulsant activity. The tricyclic compounds 6a, c, e, f, m, o and p and two bicyclic derivatives 4f and 4o were tested. The pharmacological screening results are reported and discussed.
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26
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Synthesis and pharmacological properties of thieno[2',3':4,5]pyrimido [2,1-b][1,3,4]thiadiazine derivatives. FARMACO (SOCIETA CHIMICA ITALIANA : 1989) 1995; 50:605-9. [PMID: 7495471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A new series of 2-substituted-7,8-dimethyl-3H,9H-thieno[2',3':4,5]pyrimido[2,1- b][1,3,4]thiadiazin-9-ones 5a-d and 6a,b was synthesized through the hydrazinium(1+) salt of 3-amino-2,3-dihydro-5,6-dimethyl-2-thioxo- thieno[2,3-d]pyrimidin-4(1H)-one, 2. These derivatives and two analogs 10a,b were tested for their analgesic and antiinflammatory properties. The pharmacological results are discussed in comparison with those of related compounds previously tested.
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27
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Synthesis and pharmacological properties of benzothiazole, 1,3-4-oxadiazole and 1,3,4-thiadiazole derivatives. DIE PHARMAZIE 1994; 49:880-4. [PMID: 7838878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The reaction of the 2-amino-substituted 1,3,4-oxadiazoles 9, 10 and the benzothiazoles 11, 12 with ethyl cyanoacetate is described. The obtained cyanoacetamide derivatives 13-16 gave the benzylidene derivatives 18-21 by condensation with benzaldehyde. 2-Phenyl-5-amino-1,3,4-oxadiazolo[3,2-a]pyrimidin-7-one (17) was also obtained. Moreover, the preparation of 6,7,8,9-tetraydro-5H-1,3,4-thiadiazolo[2,3-b]quinazolin++ +-5-thio-derivatives 22-25 and N-(1,3,4-thiadiazol-2-yl-5-substituted)-3,4-5,6-tetrahydro-anthran ilic acids 26-29 is also described. All above compounds and compounds, related to them, 1-8 were tested for their analgesic and antiinflammatory activities and the pharmacological screening results are reported and discussed.
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28
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Synthesis of 2,3-dihydro-3-amino-6-phenyl-2-thioxothieno [2,3-d] pyrimidin-4 (1H)-one and of potential antiinflammatory agents 2-aryl-7-phenyl-3H, 9H-pyrimido [2,1-b]thieno-[2',3':4,5]]1,3,4] thiadiazin-9-ones. DIE PHARMAZIE 1994; 49:64-5. [PMID: 8140133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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29
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Synthesis and pharmacological properties of benzothienothiadiazolopyrimidine derivatives. III. IL FARMACO; EDIZIONE SCIENTIFICA 1987; 42:437-47. [PMID: 3498650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
2-Substituted derivatives of 5H-benzothieno [3,2-d] [1,3,4]-thiadiazolo [3,2-a]pyrimidin-5-one and of 10H-benzothieno [2,3-d] [1,3,4]-thiadiazolo [3,2-a]pyrimidin-10-one have been synthesized. The analgesic, antiinflammatory and ulcerogenic activities of these derivatives were evaluated. Some derivatives showed an analgesic activity similar to or a little lower than that of indomethacin, and much higher than that of mefenamic acid, acetylsalicyclic acid and phenylbutazone, with a lower acute toxicity and a better gastric tolerance.
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30
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Electron impact mass spectra of 1,3,4-thiadiazolo[3,2-a]pyrimidin-7-one and isomeric-5-one derivatives. ACTA ACUST UNITED AC 1984. [DOI: 10.1002/oms.1210190906] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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31
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[A new nitrogen-containing polycyclic system. Synthesis and pharmacologic properties of benzofuran and thienothiadiazolepyrimidine derivatives. I]. IL FARMACO; EDIZIONE SCIENTIFICA 1983; 38:762-74. [PMID: 6605880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A series of 5H-benzofuro[3,2-d]1,3,4-thiadiazolo[3,2-a]-pyrimidin-5-ones and 1,3,4-thiadiazolo[3,2-a]thieno[2,3-d]pyrimidin-5-ones were synthesized and their analgesic, antiinflammatory, antiexudative and ulcerogenic activities were evaluated. The analgesic and antiexudative activities of several derivatives proved to be less than that of indomethacin and much higher than that of mefenamic and acetylsalicylic acids. Acute toxicity and ulcerogenic effects were significantly lower than those of reference drugs.
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32
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[Thiourea derivatives of naphtho [1,2-d] thiazole and their cyclization products]. IL FARMACO; EDIZIONE SCIENTIFICA 1983; 38:232-41. [PMID: 6862000 DOI: 10.1002/chin.198338209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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33
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Abstract
Serum concentrations of triiodothyronine (T-3), thyroxine (T-4) and myoglobin were determined by radioimmunoassay in 10 hypothyroid, 15 hyperthyroid and 14 euthyroid aged patients. The average ages were between 69 and 71 yr for these groups. The serum levels of T-3 and T-4 were typical for the clinical diagnosis and were accompanied by characteristic changes in the serum myoglobin concentrations. The hypothyroid, the euthyroid and the hyperthyroid groups displayed 107.0, 33.1 and 17.0 ng myoglobin per ml of serum, respectively. These differences are statistically highly significant. The authors are of the opinion that the serum myoglobin level depends on the myoglobin content of the muscle tissue, being higher in hypothyroid and lower in hyperthyroid patients as compared to the euthyroid persons.
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34
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[Synthesis and pharmacological activity of 1,3,4-thiadiazolo[2,-3-b]benzo[g]quinazolin-5-one and benzo[g]quinazolin-4-one derivatives]. IL FARMACO; EDIZIONE SCIENTIFICA 1982; 37:486-93. [PMID: 6982178 DOI: 10.1002/chin.198248259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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35
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[Synthesis and antimycotic activity of derivatives of 1, 3, 4-thiadiazole (3,2a) pyrimidone]. IL FARMACO; EDIZIONE SCIENTIFICA 1981; 36:983-93. [PMID: 7319024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
As a continuation of previous research designed to obtain derivatives of 1,3,4-thiadiazole of pharmacological interest, some derivatives of 1,3,4-thiadiazole[3,2-alpha]pyrimidin-5-one and isomeric 7-one were prepared. The fungistatic activity of the products was tested in vitro against the following: Candida albicans, Candida parapsilosis, Candida tropicalis, Cryptococcus neoformans e Trichophyton rubrum. No relevant antifungal activity was observed for any of the compounds examined.
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36
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[Chemical and pharmacological research on derivatives of 2,7-substituted 5H-1,3,4-thia(oxa)diazol[2,3-b]quinazolin-5-one]. IL FARMACO; EDIZIONE SCIENTIFICA 1981; 36:292-301. [PMID: 7250363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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37
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[Synthesis of 2,6-substituted derivatives of 5H-1.3.4-thiadiazolo[3,2a]-s-triazine-5,7-dione]. IL FARMACO; EDIZIONE SCIENTIFICA 1978; 33:972-83. [PMID: 311300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The synthesis of derivatives of 5H-1,3,4-thiadiazolo[3,2-a]-s-triazine-5,7-dione substituted in position 2 and 6 is described. The compounds were subjected to pharmacological screening, and some were found to possess antiinflammatory and antipyretic properties.
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38
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[Synthesis and evaluation of the antibacterial activity of benzothiazole derivatives of 1,3,4-thiadiazole and immidazo/2,1-b/1,3,4-thiadiazole]. IL FARMACO; EDIZIONE SCIENTIFICA 1976; 31:41-8. [PMID: 939318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The synthesis and chemical properties of some derivatives of 1,3,4-thiadiazole and imidazo (2,1-b) 1,3,4-thiadiazole are described. These substances were prepared in order to study their antimicrobial activity.
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39
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[Thiourea derivatives of 1,3,4-thiadiazole and their cyclization products]. IL FARMACO; EDIZIONE SCIENTIFICA 1975; 30:1031-8. [PMID: 1204830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The synthesis and chemical behaviour of 1-methoxycarbonyl-3-(1,3,4-thiadiazol-2-yl)thyoureas and 7-alkyl-2-methyltio-1,3,4-thiadiazolo [3,2-a]-s-triazine-4-ones is described. All compounds were tested in vitro for their antibacterial activity.
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40
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[Synthesis and antibacterial activity of N-(benzothiazolyl-2-carbonyl)-N-1-(2-thiazolyl)hydrazine]. IL FARMACO; EDIZIONE SCIENTIFICA 1975; 30:70-80. [PMID: 803904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The synthesis and chemical behaviour of N-(benzothiazolyl-2-carbonyl)-N-1-(2-thiazolyl)hydrazines is described. All the products were screened in vitro for antimicrobial activity. Some of them were found to give positive results.
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