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1.
J Pharm Biomed Anal ; 244: 116119, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38579409

ABSTRACT

The use of TDM in clinical practice to monitor the plasma levels of antibiotics administered to critically ill patients is a well-established approach that allows for optimization of the patient's response to drug therapy, considering the characteristics of the drug, the clinical and physiological status of the patient and any peculiar of the pathogen that caused the clinical picture. In our laboratory, we have developed a single LC-MS/MS analysis for dosing the serum concentration of an antibacterial panel composed of eight antibacterial and two selective inhibitors. The method presented used a certified material furnished by a commercial company and was internally validated using the EMA guidelines. The results have shown high sensitivity, precision, and accuracy, a lower matrix effect combined with simple sample preparation and a time-saving procedure. We have evaluated the recovery rate and matrix effect by testing serum samples without pathological index and serum pools obtained from haemolysed, icteric, or lipemic samples. The assay has shown a recovery range between 94% and 101%.


Subject(s)
Anti-Bacterial Agents , Drug Monitoring , Tandem Mass Spectrometry , Tandem Mass Spectrometry/methods , Humans , Anti-Bacterial Agents/blood , Drug Monitoring/methods , Chromatography, Liquid/methods , Reproducibility of Results , Chromatography, High Pressure Liquid/methods , Liquid Chromatography-Mass Spectrometry
2.
Pediatr Infect Dis J ; 42(11): 975-982, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37523585

ABSTRACT

OBJECTIVES: To explore the relationship between real-time therapeutic drug monitoring (TDM)-guided pharmacodynamic target attainment of continuous infusion (CI) beta-lactam monotherapy and microbiological outcome in the treatment of critically ill children with severe documented Gram-negative infections. METHODS: Observational, monocentric, retrospective study of critically ill patients receiving CI piperacillin-tazobactam, ceftazidime, or meropenem in monotherapy for documented Gram-negative infections optimized by means of a real-time TDM-guided strategy. Average steady-state beta-lactam concentrations (C ss ) were calculated for each patient, and the beta-lactam C ss /minimum inhibitory concentration (MIC) ratio was selected as a pharmacodynamic parameter of efficacy. The C ss /MIC ratio was defined as optimal if ≥4, quasi-optimal if between 1 and 4, and suboptimal if <1. The relationship between C ss /MIC and microbiological outcome was assessed. RESULTS: Forty-six TDM assessments were carried out in 21 patients [median age 2 (interquartile range: 1-8) years]. C ss /MIC ratios were optimal in 76.2% of cases. Patients with optimal C ss /MIC ratios had both a significantly higher microbiological eradication rate (75.0% vs. 0.0%; P = 0.006) and lower resistance development rate (25.0% vs. 80.0%; P = 0.047) than those with quasi-optimal or suboptimal C ss /MIC ratios. Quasi-optimal/suboptimal C ss /MIC ratio occurred more frequently when patients had infections caused by pathogens with MIC values above the European Committee on Antimicrobial Susceptibility Testing clinical breakpoint (100.0% vs. 6.3%; P < 0.001). CONCLUSIONS: Real-time TDM-guided pharmacodynamic target attainment of CI beta-lactam monotherapy allowed to maximize treatment efficacy in most critically ill children with severe Gram-negative infections. Attaining early optimal C ss /MIC ratios of CI beta-lactams could be a key determinant associated with microbiologic eradication during the treatment of Gram-negative infections. Larger prospective studies are warranted for confirming our findings.

3.
Int J Antimicrob Agents ; 62(2): 106884, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37302773

ABSTRACT

OBJECTIVES: Therapeutic drug monitoring (TDM) may be helpful in tailoring antimicrobial treatment, and expert interpretation of the results may make it more clinically useful. METHODS: This study aimed to assess retrospectively the first-year impact (July 2021 to June 2022) of a newly established expert clinical pharmacological advice (ECPA) programme based on TDM results in tailoring therapy with 18 antimicrobials hospital-wide in a tertiary university hospital. All patients having ≥1 ECPA were grouped in five cohorts [haematology, intensive care unit (ICU), paediatrics, medical wards and surgical wards]. Four indicators of performance were identified: total ECPAs; total ECPAs recommending dosing adjustments/total ECPAs both at first and at subsequent assessments; and turnaround time (TAT) of ECPAs, defined as optimal (<12 h), quasi-optimal (12-24 h), acceptable (24-48 h) or suboptimal (>48 h). RESULTS: A total of 8484 ECPAs were provided for tailoring treatment in 2961 patients, mostly admitted in the ICU (34.1%) and medical wards (32.0%). The proportion of ECPAs recommending dosing adjustments was >40% at first assessment (40.9% haematology; 62.9% ICU; 53.9% paediatrics; 59.1% medical wards; and 59.7% surgical wards), and decreased consistently at subsequent TDM assessments (20.7% haematology; 40.6% ICU; 37.4% paediatrics; 32.9% medical wards; and 29.2% surgical wards). The overall median TAT of the ECPAs was optimal (8.11 h). CONCLUSION: The TDM-guided ECPA programme was successful in tailoring treatment with a wide panel of antimicrobials hospital-wide. Expert interpretation by medical clinical pharmacologists, short TATs, and strict interaction with infectious diseases consultants and clinicians were crucial in achieving this.


Subject(s)
Anti-Infective Agents , Drug Monitoring , Humans , Child , Drug Monitoring/methods , Retrospective Studies , Anti-Infective Agents/therapeutic use , Tertiary Care Centers , Hospitals, University
4.
Antibiotics (Basel) ; 11(8)2022 Aug 01.
Article in English | MEDLINE | ID: mdl-36009906

ABSTRACT

(1) Objective: To describe the usefulness of a real-time therapeutic drug monitoring (TDM)-based strategy for optimizing pharmacokinetic/pharmacodynamic (PK/PD) target attainment of continuous infusion (CI) ampicillin-based regimens in a case series of patients affected by suspected or documented enterococcal bloodstream infections (BSIs) and/or infective endocarditis (IE). (2) Methods: Patients treated with CI ampicillin-based regimens for documented or suspected enterococcal BSI/IE who underwent real-time therapeutic drug monitoring (TDM)-based expert clinical pharmacological advice (ECPA) between June 2021 and May 2022 were retrospectively assessed. Ampicillin concentrations were determined at steady state, and the free fraction (fCss) was calculated according to a plasma protein binding of 20%. The fCss/MIC ratio was selected as the PD parameter for ampicillin efficacy and was defined as optimal for values between 4 and 8. The requirement for TDM-guided ampicillin dosing adjustments was assessed. (3) Results: Data for 12 patients with documented (n = 10) or suspected (n = 2) enterococcal infections (7 with BSIs and 5 with IE) were retrieved. The ampicillin PK/PD target was optimal over time in all of the 10 documented infections. None of the enterococcal BSIs persisted. Following the first real-time TDM-based ECPA, ampicillin dosage was decreased by >50% in 11 out of 12 patients (91.7%). (4) Conclusions: CI may be helpful in attaining aggressive ampicillin PK/PD targets in patients affected by enterococcal BSIs and/or IE. Administration of CI ampicillin after loading coupled with real-time TDM-based ECPA could be a valuable strategy for managing enterococcal infections.

5.
Crit Care ; 26(1): 178, 2022 06 14.
Article in English | MEDLINE | ID: mdl-35701812

ABSTRACT

BACKGROUND: Therapeutic drug monitoring (TDM) may represent an invaluable tool for optimizing antimicrobial therapy in septic patients, but extensive use is burdened by barriers. The aim of this study was to assess the impact of a newly established expert clinical pharmacological advice (ECPA) program in improving the clinical usefulness of an already existing TDM program for emerging candidates in tailoring antimicrobial therapy among critically ill patients. METHODS: This retrospective observational study included an organizational phase (OP) and an assessment phase (AP). During the OP (January-June 2021), specific actions were organized by MD clinical pharmacologists together with bioanalytical experts, clinical engineers, and ICU clinicians. During the AP (July-December 2021), the impact of these actions in optimizing antimicrobial treatment of the critically ill patients was assessed. Four indicators of performance of the TDM-guided real-time ECPA program were identified [total TDM-guided ECPAs July-December 2021/total TDM results July-December 2020; total ECPA dosing adjustments/total delivered ECPAs both at first assessment and overall; and turnaround time (TAT) of ECPAs, defined as optimal (< 12 h), quasi-optimal (12-24 h), acceptable (24-48 h), suboptimal (> 48 h)]. RESULTS: The OP allowed to implement new organizational procedures, to create a dedicated pathway in the intranet system, to offer educational webinars on clinical pharmacology of antimicrobials, and to establish a multidisciplinary team at the morning bedside ICU meeting. In the AP, a total of 640 ECPAs were provided for optimizing 261 courses of antimicrobial therapy in 166 critically ill patients. ECPAs concerned mainly piperacillin-tazobactam (41.8%) and meropenem (24.9%), and also other antimicrobials had ≥ 10 ECPAs (ceftazidime, ciprofloxacin, fluconazole, ganciclovir, levofloxacin, and linezolid). Overall, the pre-post-increase in TDM activity was of 13.3-fold. TDM-guided dosing adjustments were recommended at first assessment in 61.7% of ECPAs (10.7% increases and 51.0% decreases), and overall in 45.0% of ECPAs (10.0% increases and 35.0% decreases). The overall median TAT was optimal (7.7 h) and that of each single agent was always optimal or quasi-optimal. CONCLUSIONS: Multidisciplinary approach and timely expert interpretation of TDM results by MD Clinical Pharmacologists could represent cornerstones in improving the cost-effectiveness of an antimicrobial TDM program for emerging TDM candidates.


Subject(s)
Anti-Infective Agents , Drug Monitoring , Anti-Bacterial Agents , Anti-Infective Agents/therapeutic use , Critical Illness/therapy , Drug Monitoring/methods , Humans , Meropenem
6.
Front Pharmacol ; 12: 755075, 2021.
Article in English | MEDLINE | ID: mdl-34646143

ABSTRACT

Introduction: Antimicrobial treatment is quite common among hospitalized children. The dynamic age-associated physiological variations coupled with the pathophysiological alterations caused by underlying illness and potential drug-drug interactions makes the implementation of appropriate antimicrobial dosing extremely challenging among paediatrics. Therapeutic drug monitoring (TDM) may represent a valuable tool for assisting clinicians in optimizing antimicrobial exposure. Clinical pharmacological advice (CPA) is an approach based on the correct interpretation of the TDM result by the MD Clinical Pharmacologist in relation to specific underlying conditions, namely the antimicrobial susceptibility of the clinical isolate, the site of infection, the pathophysiological characteristics of the patient and/or the drug-drug interactions of cotreatments. The aim of this study was to assess the role of TDM-based CPAs in providing useful recommendations for the real-time personalization of antimicrobial dosing regimens in various paediatric settings. Materials and methods: Paediatric patients who were admitted to different settings of the IRCCS Azienda Ospedaliero-Universitaria of Bologna, Italy (paediatric intensive care unit [ICU], paediatric onco-haematology, neonatology, and emergency paediatric ward), between January 2021 and June 2021 and who received TDM-based CPAs on real-time for personalization of antimicrobial therapy were retrospectively assessed. Demographic and clinical features, CPAs delivered in relation to different settings and antimicrobials, and type of dosing adjustments were extracted. Two indicators of performance were identified. The number of dosing adjustments provided over the total number of delivered CPAs. The turnaround time (TAT) of CPAs according to a predefined scale (optimal, <12 h; quasi-optimal, between 12-24 h; acceptable, between 24-48 h; suboptimal, >48 h). Results: Overall, 247 CPAs were delivered to 53 paediatric patients (mean 4.7 ± 3.7 CPAs/patient). Most were delivered to onco-haematological patients (39.6%) and to ICU patients (35.8%), and concerned mainly isavuconazole (19.0%) and voriconazole (17.8%). Overall, CPAs suggested dosing adjustments in 37.7% of cases (24.3% increases and 13.4% decreases). Median TAT was 7.5 h (IQR 6.1-8.8 h). Overall, CPAs TAT was optimal in 91.5% of cases, and suboptimal in only 0.8% of cases. Discussion: Our study provides a proof of concept of the helpful role that TDM-based real-time CPAs may have in optimizing antimicrobial exposure in different challenging paediatric scenarios.

7.
J Sep Sci ; 43(8): 1440-1449, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32077627

ABSTRACT

In this work, a convenient method for the therapeutic monitoring of seven common antipsychotic drugs in "dried plasma spot" samples has been developed. It is based on the liquid chromatography tandem mass spectrometry technique, operating in multiple reaction monitoring mode, and a straightforward procedure for the simultaneous extraction of all antipsychotics in a single step, with high extraction yield. The method was fully validated with proper accuracy, precision, selectivity and sensitivity, for all the drugs. Limits of quantification were 0.12, 1.09, 1.46, 1.47, 5.70, 1.32, 1.33 µg/L for haloperidol, aripiprazole, olanzapine, quetiapine, clozapine, risperidone, and paliperidone, respectively. Accuracy, intra- and interday precision values were <10% for all drugs at all concentration levels examined. The method was tested in the analysis of 30 plasma samples from real patients for each drug. The proposed analytical approach, by combining practical and logistical advantages of microsampling with liquid chromatography tandem mass spectrometry analytical performance, could offer an ideal strategy for accurate and timely therapeutic drug monitoring of antipsychotic drugs in most clinical settings, even in remote centers and/or in out-patient settings, bringing so many potential improvements in psychiatric patient care.


Subject(s)
Antipsychotic Agents/blood , Dried Blood Spot Testing , Drug Monitoring , Chromatography, Liquid , Humans , Tandem Mass Spectrometry
8.
Rev. ing. bioméd ; 5(10): 31-43, jul.-dic. 2011. graf
Article in Spanish | LILACS | ID: lil-769115

ABSTRACT

La ingeniería en rehabilitación tiene entre sus objetivos principales el desarrollo de soluciones que mejoren la calidad de vida de las personas con discapacidad, las cuales, si son desarrolladas a través de metodologías de investigación y diseño participativo, pueden presentar ventajas significativas como productos que dan mejor respuesta a las necesidades de la comunidad, mayor aceptación de los resultados por parte de la misma y el hallazgo de fuentes y nichos potenciales de innovación. Adicionalmente, dichas metodologías permiten que los beneficios para esta población no se asocien solamente a los resultados o productos generados, sino que complementariamente se logren desde los mismos procesos investigativos a través de la inclusión y participación auténticas, generando un mayor impacto social. Este artículo propone un enfoque metodológico para el desarrollo de productos de habilitación y rehabilitación en el cual convergen las tendencias de investigación participativa, el diseño y la voz de la comunidad que pide ser copartícipe en los proyectos, en unión a las estrategias para la apropiación social del conocimiento. Adicionalmente se exponen ejemplos, barreras y dificultades, retos y recomendaciones para llevar a cabo una investigación según el enfoque participativo. Las reflexiones planteadas pueden además ser aplicadas a otras áreas del saber.


One of the main goals of rehabilitation engineering is improving the quality of life of people with disabilities through developing solutions for their specific needs. When participatory methodologies for research and design are applied, the resulting solutions show advantages such as products that better address the needs of the community, solutions that are better accepted by the community, and the identification of potential sources and niches for innovation. In addition, participatory methodologies provide benefits that are not only associated with the generated results and products but with the processes themselves. When research processes are inclusive and promote authentic participation a higher social impact can be obtained. This paper proposes a methodological approach for the development of habilitation and rehabilitation products that allows the convergence of participatory research tendencies, design tendencies and the voice of the community that claims for co-participation. This approach also incorporates strategies for the social appropriation of knowledge. Examples, barriers, difficulties, challenges and recommendations for conducting research with a focus on participation are also presented. The reflections herein presented may also be applied to other fields.

9.
Ann N Y Acad Sci ; 1155: 232-6, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19250209

ABSTRACT

In this randomized dietary intervention study (DI) we analyzed levels of androgens, phytoestrogens, and estrogens in 12-h urine samples of 69 healthy postmenopausal women, 37 of whom followed a traditional Mediterranean diet for 6 months (intervention group) as compared to 32 women who followed their regular diet (control group). Circulating levels of both insulin and testosterone (T) were also assayed. Overall, enterolactone (ENL) was the most prominent phytoestrogen in urines of both control and intervention women, and its levels increased by a 20% after DI. At the baseline the ENL levels were seen to be significantly associated with both the total androgens (TOT-A) (r= 0.371, P= 0.002) and the TOT-A/total estrogen (TOT-E) ratio (r= 0.351, P= 0.005) in all 69 postmenopausal women. Furthermore, the DI resulted in a more pronounced negative association of both ENL with insulin (r=-0.321, P= 0.05) and insulin with TOT-A (r=-0.421, P= 0.01). Regarding urinary androgens, ENL associated with both 3alpha-androsterone (5alpha-androgen, r= 0.363, P= 0.002) and 3alpha-etiocholanolone (5beta-androgen, r= 0.295, P= 0.01) at baseline, while after DI, circulating insulin and T exhibited a significant negative association with the 5beta-androgen metabolite etiocholanolone (r=-0.487, P= 0.002; and r=-0.336, P= 0.042, respectively). We conclude that lignan components of the Mediterranean diet, notably ENL, are associated with urinary levels of products of androgen metabolism, including both 5alpha- and 5beta-reductase enzymes, in healthy postmenopausal women. Further studies are necessary to better understand the interplay of sex hormones with dietary phytoestrogens.


Subject(s)
4-Butyrolactone/analogs & derivatives , Androgens/blood , DEET , Estrogens/blood , Lignans/administration & dosage , Postmenopause , 4-Butyrolactone/administration & dosage , 4-Butyrolactone/urine , Chromatography, High Pressure Liquid , Female , Humans , Lignans/urine , Spectrophotometry, Ultraviolet
10.
J Med Virol ; 81(1): 139-45, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19031454

ABSTRACT

Although the genetic/antigenic heterogeneity of human noroviruses (NoVs) is impressive, a few genogroup II strains of genotype 4 (GII.4) are dominant worldwide. GII.4 NoVs evolve rapidly and in the last 15 years six epidemic variants have been identified. In 2005-2006, surveillance of sporadic viral gastroenteritis in children in Palermo, Italy, resulted in the detection of NoV strains in 20.9% of the patients admitted to hospital. By restriction fragment length polymorphism (RFLP) and sequence analysis of region A in the RNA-dependent RNA-polymerase (RdRp) gene, 59 NoV strains were successfully characterized. Eighty-one percent of the strains were characterized as GII.4, 14% as GIIb/Hilversum and 5% as GI.1. Phylogenetic analysis of region A and of the ORF1/ORF2 overlapping region of the GII.4 strains recovered in Palermo in the years 2002-2006 revealed the sequential emergence of four variants, GII.4 2002, 2004, 2006a, and 2006b. The variant GII.4 2006a was detected in June and July, 2006, while the variant 2006b first appeared in August, 2006, becoming predominant thereafter. Based on these findings, the dynamics of replacement and circulation of the GII.4 NoV variants in Italy in 2005-2006 appear to have matched the temporal pattern observed in Europe during the same period.


Subject(s)
Caliciviridae Infections/epidemiology , Caliciviridae Infections/virology , Gastroenteritis/epidemiology , Gastroenteritis/virology , Norovirus/classification , Norovirus/isolation & purification , Child, Preschool , Cluster Analysis , DNA Fingerprinting , Genotype , Humans , Italy/epidemiology , Molecular Epidemiology , Molecular Sequence Data , Norovirus/genetics , Phylogeny , Polymorphism, Restriction Fragment Length , RNA, Viral/genetics , Sequence Analysis, DNA , Sequence Homology
11.
J Virol Methods ; 147(2): 250-6, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17953996

ABSTRACT

GII.4 and GIIb/Hilversum norovirus (NoV) strains appear to have a prominent epidemiological role in outbreaks or sporadic cases of human gastroenteritis. Sequence analysis, although laborious, is the reference method used for characterization of noroviruses. In this study a screening test is proposed to characterize GIIb and GII.4 NoVs based on restriction fragment length polymorphism (RFLP) analysis of amplicons obtained from the RNA-dependent RNA polymerase (RdRp) region. Virtual analysis of 793 RdRp sequences of GGI and GGII NoVs, retrieved from GenBank, and representative of global geographical origins on a long-time period, permitted the selection of four restriction enzymes, XmnI, AhdI, BstXI, and AcuI, suitable for correct identification of GIIb and GII.4 NoV genotypes. Experimental analysis by the RT-PCR RFLP analysis of 41 NoV strains detected in Palermo during the years 2002-2005 allowed to recognize all the Italian strains as belonging to GIIb/Hilversum or GII.4, and sequence analysis confirmed these results. The PCR-RFLP protocol developed in this study proved to be a simple and reliable proxy for sequence-based classification of the GIIb/Hilversum and GII.4 NoV variants displaying high specificity (100%) and sensitivity (94%).


Subject(s)
Caliciviridae Infections/virology , Norovirus/classification , Polymorphism, Restriction Fragment Length , Reverse Transcriptase Polymerase Chain Reaction , Child, Preschool , Gastroenteritis/virology , Genotype , Humans , Infant , Norovirus/genetics , Norovirus/isolation & purification , RNA, Viral/isolation & purification
12.
Emerg Infect Dis ; 13(9): 1389-91, 2007 Sep.
Article in English | MEDLINE | ID: mdl-18252118

ABSTRACT

Noroviruses were detected in 48.4% of 192 children (<3 years of age) hospitalized for gastroenteritis in Palermo, Italy, during 2004; predominant genotypes were GGIIb/Hilversum and GGII.4 Hunter. Of children with viral enteritis, 19.6% had a mixed norovirus-rotavirus infection. The severity of infection was lower for norovirus than for rotavirus but increased in co-infection.


Subject(s)
Caliciviridae Infections/epidemiology , Gastroenteritis/epidemiology , Gastroenteritis/virology , Norovirus/isolation & purification , Caliciviridae Infections/virology , Female , Humans , Infant , Italy/epidemiology , Male
13.
Emerg Infect Dis ; 13(7): 1091-3, 2007 Jul.
Article in English | MEDLINE | ID: mdl-18214189

ABSTRACT

Infection by an animal-like strain of rotavirus (PA260/97) was diagnosed in a child with gastroenteritis in Palermo, Italy, in 1997. Sequence analysis of VP7, VP4, VP6, and NSP4 genes showed resemblance to a G3P[3] canine strain identified in Italy in 1996. Dogs are a potential source of human viral pathogens.


Subject(s)
Dog Diseases/transmission , Gastroenteritis/virology , Rotavirus Infections/transmission , Rotavirus/genetics , Zoonoses , Acute Disease , Animals , Child, Preschool , Disease Reservoirs/veterinary , Disease Reservoirs/virology , Dog Diseases/virology , Dogs , Genotype , Humans , Phylogeny , Polymerase Chain Reaction/methods , Rotavirus/classification , Rotavirus/isolation & purification , Rotavirus Infections/veterinary , Rotavirus Infections/virology , Sequence Homology , Species Specificity
14.
J Med Virol ; 78(12): 1656-62, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17063517

ABSTRACT

Noroviruses (NoVs) are important enteric pathogens of humans. Although they exhibit an impressive genetic diversity, few NoV strains appear to predominate worldwide. Limited epidemiological data are available on NoV gastroenteritis in Italy. In this study, we assessed the prevalence of human NoV in Italian children with gastroenteritis by using a reverse-transcription nested polymerase chain reaction (RT-PCR) assay specific for the RNA-dependent RNA polymerase (RdRp) on faecal samples collected throughout the 2004 surveillance activity in Palermo, Italy. NoVs were detected in 47% of the stool samples obtained from children <5 years age, admitted to hospital with acute non-bacterial gastroenteritis. A selection of strains was further analyzed by partial sequence analysis of the RdRp gene. The strains were characterized as genogroup (GG) II and clustered into two distinct virus populations that resembled the emerging European GGIIb/Hilversum strains and the Australian Hunter GGII.4 strains. A temporal pattern of distribution of the two NoV strains was observed which was consistent with an independent circulation of two separate strains in the local population. Based on this 1-year study we concluded that NoVs were a diffuse cause of sporadic cases of acute childhood gastroenteritis and that strains of global epidemiological relevance were circulating in Palermo, Italy in 2004.


Subject(s)
Caliciviridae Infections/epidemiology , Gastroenteritis/epidemiology , Genetic Variation , Molecular Epidemiology , Norovirus/classification , Norovirus/isolation & purification , Caliciviridae Infections/virology , Feces/virology , Gastroenteritis/virology , Humans , Infant , Italy/epidemiology , Norovirus/genetics , Phylogeny , RNA, Viral/analysis , RNA, Viral/isolation & purification , RNA-Dependent RNA Polymerase/genetics , Reverse Transcriptase Polymerase Chain Reaction , Sequence Analysis, DNA
15.
J Virol ; 80(21): 10724-33, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16928744

ABSTRACT

A rotavirus sample collection from 19 consecutive years was used to investigate the heterogeneity and the dynamics of evolution of G1 rotavirus strains in a geographically defined population. Phylogenetic analysis of the VP7 gene sequences of G1P[8] human rotavirus strains showed the circulation of a heterogeneous population comprising three lineages and seven sublineages. Increases in the circulation of G1 rotaviruses were apparently associated with the introduction of novel G1 strains that exhibited multiple amino acid changes in antigenic regions involved in rotavirus neutralization compared to the strains circulating in the previous years. The emergence and/or introduction of G1 antigenic variants might be responsible for the continuous circulation of G1 rotaviruses in the local population, with the various lineages and sublineages appearing, disappearing, or cocirculating in an alternate fashion under the influence of immune-pressure mechanisms. Sequence analysis of VP4-encoding genes of the G1 strains revealed that the older strains were associated with a unique VP4 lineage, while a novel VP4 lineage emerged after 1995. The introduction of human rotavirus vaccines might alter the forces and balances that drive rotavirus evolution and determine the spread of novel strains that are antigenically different from those included in the vaccine formulations. The continuous emergence of VP7-VP4 gene combinations in human rotavirus strains should be taken into consideration when devising vaccination strategies.


Subject(s)
Evolution, Molecular , Rotavirus/genetics , Amino Acid Sequence , Antigens, Viral/genetics , Capsid Proteins/genetics , Child, Preschool , Genes, Viral , Humans , Infant , Italy/epidemiology , Longitudinal Studies , Molecular Sequence Data , Phylogeny , RNA-Binding Proteins/genetics , Rotavirus/classification , Rotavirus/isolation & purification , Rotavirus Infections/epidemiology , Rotavirus Infections/virology , Sequence Homology, Amino Acid , Serotyping , Viral Nonstructural Proteins/genetics
16.
Water Res ; 39(11): 2273-80, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15941575

ABSTRACT

An insoluble material of polysaccharidic nature has been obtained by thermal alkali treatment of the filamentous fungus Phomopsis sp. FT-IR spectrum of the resulting material as well as its nitrogen content suggest that chitosan and glucans are the main components of the biomaterial. Information on Lewis base sites has also been obtained and used as a guideline in the evaluation of the complexing ability against a number of metal ions in aqueous media at pH in the range 4--6. Results indicate that after 24h contact time, up to 870 micromol/g of lead, 390 micromol/g of copper, 230 micromol/g of cadmium, 150 micromol/g of zinc and 110 micromol/g of nickel ions are adsorbed into the material. After approximately 10 min, about 70% of the overall adsorption process has already been completed. Adsorbed metal ions can be recovered by washing with dilute acid. Experiments have been extended to a real wastewater effluent confirming the potential of this biomaterial as a depolluting agent.


Subject(s)
Ascomycota/chemistry , Ions/chemistry , Metals/chemistry , Polysaccharides/chemistry , Water/chemistry , Cell Wall/chemistry , Sewage/chemistry
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