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2.
Radiat Res ; 189(5): 541-547, 2018 05.
Article in English | MEDLINE | ID: mdl-29547352

ABSTRACT

We investigated the association between environmental exposure to radiofrequency electromagnetic fields (RF-EMF) and risk of lymphoma subtypes in a case-control study comprised of 322 patients and 444 individuals serving as controls in Sardinia, Italy in 1998-2004. Questionnaire information included the self-reported distance of the three longest held residential addresses from fixed radio-television transmitters and mobile phone base stations. We georeferenced the residential addresses of all study subjects and obtained the spatial coordinates of mobile phone base stations. For each address within a 500-meter radius from a mobile phone base station, we estimated the RF-EMF intensity using predictions from spatial models, and we performed RF-EMF measurements at the door in the subset of the longest held addresses within a 250-meter radius. We calculated risk of lymphoma and its major subtypes associated with the RF-EMF exposure metrics with unconditional logistic regression, adjusting by age, gender and years of education. In the analysis of self-reported data, risk associated with residence in proximity (within 50 meters) to fixed radio-television transmitters was likewise elevated for lymphoma overall [odds ratio = 2.7, 95% confidence interval = 1.5-4.6], and for the major lymphoma subtypes. With reference to mobile phone base stations, we did not observe an association with either the self-reported, or the geocoded distance from mobile phone base stations. RF-EMF measurements did not vary by case-control status. By comparing the self-reports to the geocoded data, we discovered that the cases tended to underestimate the distance from mobile phone base stations differentially from the controls ( P = 0.073). The interpretation of our findings is compromised by the limited study size, particularly in the analysis of the individual lymphoma subtypes, and the unavailability of the spatial coordinates of radio-television transmitters. Nonetheless, our results do not support the hypothesis of a link between environmental exposure to RF-EMF from mobile phone base stations and risk of lymphoma subtypes.


Subject(s)
Electromagnetic Fields/adverse effects , Lymphoma/etiology , Neoplasms, Radiation-Induced/etiology , Radiation Exposure/adverse effects , Radio Waves/adverse effects , Adult , Aged , Case-Control Studies , Cell Phone , Female , Humans , Lymphoma/epidemiology , Male , Middle Aged , Neoplasms, Radiation-Induced/epidemiology , Risk Assessment
3.
Clin Microbiol Infect ; 24(6): 604-609, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29108952

ABSTRACT

BACKGROUND: Nearly two decades after completion of the genome sequence of Mycobacterium tuberculosis (MTB), and with the advent of next generation sequencing technologies (NGS), whole-genome sequencing (WGS) has been applied to a wide range of clinical scenarios. Starting in 2017, England is the first country in the world to pioneer its use on a national scale for the diagnosis of tuberculosis, detection of drug resistance, and typing of MTB. AIMS: This narrative review critically analyses the current applications of WGS for MTB and explains how close we are to realizing its full potential as a diagnostic, epidemiologic, and research tool. SOURCES: We searched for reports (both original articles and reviews) published in English up to 31 May 2017, with combinations of the following keywords: whole-genome sequencing, Mycobacterium, and tuberculosis. MEDLINE, Embase, and Scopus were used as search engines. We included articles that covered different aspects of whole-genome sequencing in relation to MTB. CONTENT: This review focuses on three main themes: the role of WGS for the prediction of drug susceptibility, MTB outbreak investigation and genetic diversity, and research applications of NGS. IMPLICATIONS: Many of the original expectations have been accomplished, and we believe that with its unprecedented sensitivity and power, WGS has the potential to address many unanswered questions in the near future. However, caution is still needed when interpreting WGS data as there are some important limitations to be aware of, from correct interpretation of drug susceptibilities to the bioinformatic support needed.


Subject(s)
High-Throughput Nucleotide Sequencing/methods , Mycobacterium tuberculosis/genetics , Tuberculosis/epidemiology , Whole Genome Sequencing/methods , Anti-Bacterial Agents/pharmacology , Bacterial Typing Techniques , Disease Outbreaks , Drug Resistance, Bacterial , Genome, Bacterial , Humans , Tuberculosis/microbiology
4.
Clin Microbiol Infect ; 23(2): 69-72, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27642177

ABSTRACT

Whole genome sequencing (WGS) has the potential to revolutionize the diagnosis of Mycobacterium tuberculosis infection but the lack of bioinformatic expertise among clinical microbiologists is a barrier for adoption. Software products for analysis should be simple, free of charge, able to accept data directly from the sequencer (FASTQ files) and to provide the basic functionalities all-in-one. The main aim of this narrative review is to provide a practical guide for the clinical microbiologist, with little or no practical experience of WGS analysis, with a specific focus on software products tailor-made for M. tuberculosis analysis. With sequencing performed by an external provider, it is now feasible to implement WGS analysis in the routine clinical practice of any microbiology laboratory, with the potential to detect resistance weeks before traditional phenotypic culture methods, but the clinical microbiologist should be aware of the limitations of this approach.


Subject(s)
Genome, Bacterial , Mycobacterium tuberculosis/genetics , Sequence Analysis, DNA , Tuberculosis/diagnosis , Tuberculosis/microbiology , Antitubercular Agents/pharmacology , Bacterial Typing Techniques/methods , Bacterial Typing Techniques/standards , Computational Biology/methods , Humans , Microbial Sensitivity Tests , Mycobacterium tuberculosis/classification , Mycobacterium tuberculosis/drug effects , Phylogeny , Software , Web Browser
5.
G Ital Med Lav Ergon ; 34(3 Suppl): 599-601, 2012.
Article in Italian | MEDLINE | ID: mdl-23405727

ABSTRACT

INTRODUCTION: We evaluated the congenital malformation rate in the progeny of the personnel of the Salto di Quirra military base in Sardinia. METHODS: During 2011, we gathered questionnaire information on the reproductive history of 389 employees, more then 99% of those eligible for routine health surveillance. RESULTS: the observed congenital malformation rate (20.1 x 10(-3), 95% CI 6.3 - 33.8) was lower than that reported by the Italian Registries of Congenital Malformations, and it did not vary by exposure to radiofrequency, elf electromagnetic fields, and solvents, and by jobs associated with alleged exposure to nanoparticles or alpha radiation. CONCLUSIONS: Our findings suggest that the documented or alleged occupational exposures among the PISQ workforce did not increase the congenital malformation rate in the progeny.


Subject(s)
Congenital Abnormalities/epidemiology , Congenital Abnormalities/genetics , Military Personnel , Adult , Humans , Italy , Military Facilities , Risk Assessment
6.
G Ital Med Lav Ergon ; 34(3 Suppl): 621-3, 2012.
Article in Italian | MEDLINE | ID: mdl-23405733

ABSTRACT

INTRODUCTION: We explored the association between use of mobile phones and lymphoma risk in a case-control study. METHODS: We conducted unconditional logistic regression analysis in 322 lymphoma cases and 446 population controls, adjusting by age, gender and education. RESULTS: Risk of lymphoma (all types; OR = 1.5; 95% CI 1.0 - 2.1), and chronic lymphocytic leukaemia (OR = 1.8; 95% CI 1.0 - 3.4) was elevated in subjects reporting use of mobile phones, but it decreased with duration of use, and years from first purchase. CONCLUSIONS: Our contradictory findings would not support the aetiological nature of the observed associations.


Subject(s)
Cell Phone/statistics & numerical data , Lymphoma/classification , Lymphoma/epidemiology , Adult , Aged , Case-Control Studies , Humans , Middle Aged , Risk Factors
7.
Bone Marrow Transplant ; 46(5): 727-32, 2011 May.
Article in English | MEDLINE | ID: mdl-20818449

ABSTRACT

Oral mucositis (OM) is a common side effect experienced during haematopoietic SCT (HSCT), and it can have a significant impact on the quality of life of patients. A descriptive nurse-led study was undertaken in 19-member centres of the Italian national transplant group (GITMO) evaluating incidence, severity and duration of OM in patients undergoing HSCT. Data from 1841 patients between 2002 and 2006 was analyzed. Initial medical history and oral cavity assessment was performed. Assessment was repeated on the day of transplant, then daily, using the WHO (World Health Organisation) oral toxicity scale. A total of 71% of the patients evaluated developed mucositis and 21.6% developed severe mucositis. Duration of OM in most cases lasted for 10-14 days and resolved along with marrow reconstitution. Oral mucostitis is a frequent side effect in patients undergoing HSCT. The onset of severe mucositis seems to be related to the conditioning regimen used. This database provides a descriptive overview of the incidence and severity of mucositis and has encouraged participating centres to adopt routine evaluation and measurement of the oral cavity. The assessment tools are still used in some centres, providing a basis for further collaborative research projects.


Subject(s)
Hematopoietic Stem Cell Transplantation/adverse effects , Stomatitis/epidemiology , Transplantation Conditioning/adverse effects , Adolescent , Adult , Aged , Child , Child, Preschool , Female , Hematopoietic Stem Cell Transplantation/nursing , Humans , Incidence , Infant , Italy/epidemiology , Male , Middle Aged , Stomatitis/etiology , Transplantation Conditioning/nursing
8.
Zoonoses Public Health ; 57(7-8): e102-8, 2010 Dec.
Article in English | MEDLINE | ID: mdl-19968848

ABSTRACT

An outbreak of toxoplasmosis occurring in a typical farm of 524 ovines was monitored for 1 year after the occurrence of 31 abortions. Abortion events involved 7.2% of 430 pregnant sheep. Presence of antibodies to Toxoplasma gondii in sheep sera was investigated by the indirect fluorescence antibody test (IFAT). A total of 422 ewes were bled four times during the year, and an epidemiological analysis was performed on all serology data collected in this subgroup. The prevalence of IgG positives ranged from 31.52% (133/422) at the first sampling to 62.56% (264/422) at the fourth sampling. Incidence of IgG antibodies was 38.75% at the second sampling, 14.92% at the third and 29.28% at the fourth sampling. At the beginning of the study, prevalence was 70.7% in primiparous sheep and 20.9% in sheep older than 5 years; at the third sampling, prevalence was stable at 70% in pluriparous sheep. The mean prevalence of IgM antibodies was 14.87%. A total of 147 out of all 524 ovines of the flock tested positive for IgM in more than one sampling. After an initial positivity, 60 sheep tested negative for IgG at the following serological controls (4 between the first and the second sampling, 30 between the second and the third and 28 between the third and the fourth sampling). One stray cat was positive for IgG, with a titre of 1 : 320. Moreover, one of the farmers was also positive, with a titre of 1 : 160 for IgG. A positive PCR result for T. gondii DNA was also observed in aliquots of grain and pellets taken from feed stocks amassed inside the sheds without protection, suggesting that an adequate management of the farm might be useful, if not essential, for controlling T. gondii outbreaks in ovine flocks.


Subject(s)
Abortion, Veterinary/epidemiology , Antibodies, Protozoan/blood , Sheep Diseases/epidemiology , Toxoplasma/isolation & purification , Toxoplasmosis, Animal/epidemiology , Aborted Fetus/parasitology , Abortion, Veterinary/diagnosis , Abortion, Veterinary/parasitology , Animals , Breeding , Cats , DNA, Protozoan/analysis , Disease Outbreaks , Epidemiologic Studies , Female , Fluorescent Antibody Technique, Indirect/veterinary , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Incidence , Polymerase Chain Reaction/veterinary , Pregnancy , Pregnancy Complications, Parasitic/blood , Pregnancy Complications, Parasitic/epidemiology , Pregnancy Complications, Parasitic/parasitology , Prevalence , Sheep , Sheep Diseases/diagnosis , Sheep Diseases/parasitology , Toxoplasma/genetics , Toxoplasma/immunology , Toxoplasmosis, Animal/blood , Toxoplasmosis, Animal/diagnosis , Toxoplasmosis, Animal/parasitology
9.
J Viral Hepat ; 16(11): 790-5, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19413693

ABSTRACT

Liver fibrosis progress slowly in patients with chronic hepatitis C and persistently normal alanine aminotransferase (PNALT) compared to subjects with elevated aminotransferases. Differences in liver fibrosis according to human immunodeficiency virus (HIV) status in this population have not been examined. All patients with serum hepatitis C virus (HCV)-RNA and PNALT who underwent liver fibrosis assessment using elastometry since 2004 at three different European hospitals were evaluated. Patients previously treated with interferon were excluded. PNALT was defined as ALT below the upper limit of normality in at least three consecutive determinations within the last 12 months. Fibrosis stage was defined as mild (Metavir F0-F1) if stiffness < or =7.1 kPa; moderate (F2) if 7.2-9.4 kPa; severe (F3) if 9.5-14 kPa, and cirrhosis (F4) if >14 kPa. A total of 449 HIV-negative and 133 HIV-positive patients were evaluated. HIV-negative patients were older (mean age 51.8 vs 43.5 years) and more frequently females (63%vs 37%) than the HIV counterparts. Mean serum HCV-RNA was similar in both the groups (5.9 vs 5.8 log IU/mL). Overall, 78.8% of the HIV patients were on HAART and their mean CD4 count was 525 (+/-278) cells/microL. In HIV-negatives, liver fibrosis was mild in 84.6%; moderate in 8.7%, severe in 3.3% and cirrhosis was found in 3.3%. In HIV patients, these figures were 70.7%, 18.8%, 6%, and 4.5%, respectively. In the multivariate logistic regression analysis, older age (odds ratio or OR: 1.04; 95% confidence interval or CI: 1.02-1.07; P < 0.001) and being HIV+ (OR: 2.6; 95% CI: 1.21-5.85; P < 0.01) were associated with severe liver fibrosis or cirrhosis (F3-F4). Thus, severe liver fibrosis and cirrhosis are seen in 6.6% of the HCV-monoinfected and in 10.5% of HCV-HIV co-infected patients with PNALT. Some degree of liver fibrosis that justifies treatment is seen in 15% of the HCV-monoinfected but doubles to nearly 30% in HIV-HCV co-infected patients with PNALT.


Subject(s)
Alanine Transaminase/blood , HIV Infections/complications , Hepatitis C, Chronic/complications , Liver Cirrhosis/etiology , Adult , Aged , Antiretroviral Therapy, Highly Active , Elasticity Imaging Techniques , Female , Genotype , HIV Infections/drug therapy , HIV Infections/virology , HIV Seronegativity , HIV-1/genetics , HIV-1/isolation & purification , Hepacivirus/classification , Hepacivirus/genetics , Hepacivirus/isolation & purification , Hepatitis B Surface Antigens/blood , Hepatitis C, Chronic/virology , Humans , Liver Cirrhosis/pathology , Liver Cirrhosis/virology , Logistic Models , Male , Middle Aged , RNA, Viral/blood
10.
Nutr Metab Cardiovasc Dis ; 19(3): 218-25, 2009 Mar.
Article in English | MEDLINE | ID: mdl-18718745

ABSTRACT

BACKGROUND AND AIMS: In haematological and solid tumours the blood lipoprotein profile has been reported to be altered; while decreased levels of total cholesterol and increased values of triglycerides have been observed. The mechanism and meaning of these changes are, however, not fully understood. The aim of the present study was to determine relationships between cancer progression and serum lipoproteins. METHODS AND RESULTS: We performed a case-control study. We included cancer patients admitted to the 1st Division of Medical Oncology, Businco Hospital of Cagliari, Italy, between 1984 and 1998; 519 patients with any type of solid tumours and 928 healthy controls. We considered total cholesterol (C), high-density lipoprotein (HDL)-C, low-density lipoprotein (LDL)-C, triglycerides and apolipoprotein A-1; other parameters examined were glycaemia, insulinaemia, body mass index (BMI), homeostasis model assessment-estimated insulin resistance (HOMA-IR), C reactive protein (CRP) and tumour necrosis factor-alpha (TNF-alpha). In the cancer group HDL-C and apolipoprotein A-1 were lower (p<0.05) and triglycerides were higher (p<0.05) than in controls; HDL-C (mg/dl) females: 48 vs. 64; males, 40 vs. 52; Apo-A-1 (mg/dl) females: 125 vs. 173; males, 120 vs. 152; triglycerides (mg/dl) females: 133 vs. 96; males, 152 vs. 117. Glucose (mg/dl) was lower in the cancer group (p<0.05); females, 72.3 vs. 80.0; males, 75.7 vs. 78.4. CONCLUSION: Using multivariate analysis we were able to rule out cardiovascular and inflammatory diseases as causes of low HDL-C, and also demonstrate that these alterations can be shown as a specific consequence of the presence of a malignant tumour with a diagnostic and prognostic significance.


Subject(s)
Lipoproteins/blood , Neoplasms/physiopathology , Adult , Aged , Aged, 80 and over , Apolipoprotein A-I/blood , Case-Control Studies , Cholesterol, HDL/blood , Disease Progression , Female , Humans , Male , Middle Aged , Neoplasms/blood , Retrospective Studies , Sex Factors , Triglycerides/blood , Young Adult
11.
Acta Diabetol ; 46(3): 227-31, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19107322

ABSTRACT

We aimed at updating the prevalence of impaired fasting glucose (IFG) and of undiagnosed (UD) and diagnosed diabetes (DD) among the Sardinian population. The survey was carried out from 2002 to 2005 on 4.737 subjects aged 20-80+ years. IFG was diagnosed when blood glucose was 110-125 mg/dl; UD when it was >or=126 mg/dl in the absence of personal history of diabetes; DD when personal history was positive, irrespective of blood glucose value. Prevalence rates (%) were adjusted for age by direct method to the Italian 2001 population. IFG was diagnosed in 11% of the sample (9.88% in females and 12.24% in males); UD was found in 5.65% (5.20 and 6.15%, females and males, respectively), DD in 8.72% (6.74 and 10.05%); and total diabetes (TD), i.e. the sum of UD + DD, was 14.37% (12.93 and 15.07%, females and males, respectively). In Sardinia, in about 5 years there was an increase of IFG (+61.8%), UD (+56.9%), DD (+55.7%), and TD (+57.9%). Thus Sardinia participates in the worldwide increase in prevalence of diabetes and its microvascular, macrovascular, and socioeconomic consequences.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus/epidemiology , Adult , Aged , Aged, 80 and over , Diabetes Mellitus/diagnosis , Fasting/blood , Female , Humans , Italy/epidemiology , Male , Middle Aged , Prevalence , Risk Factors , Young Adult
12.
Clin Microbiol Infect ; 14(11): 1028-33, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19040474

ABSTRACT

The present study evaluated the molecular detection and identification of Rickettsia species in 83 ticks collected in Sardinia, Italy. Fifteen ticks were PCR-positive using gltA-specific and ompA-specific primers, leading to the identification of Rickettsia aeschlimannii in Hyalomma marginatum marginatum, R. massiliae in Rhipicephalus turanicus and in Rhipicephalus sanguineus, and a new rickettsia, previously referred to as PoTiRb169 in Portugal, in four Rhipicephalus turanicus. This new species was further characterized by amplification and sequencing of three additional genes (ompB, sca4 and rrs). Using the current criteria to name a rickettsia, this uncultivated rickettsia can be given a Candidatus status, and we propose to call it 'Candidatus Rickettsia barbariae'. The detection of three tick-borne rickettsiae in Sardinia raises the possibility that many cases of spotted fever considered by clinicians and health authorities as Mediterranean spotted fever due to R. conorii could, in fact, be due to other rickettsiae, including those found in this study. Analysing skin biopsies of inoculation eschars in patients with spotted fever would be, together with continuing entomological surveys, the best way to increase our knowledge of tick-borne rickettsioses in Sardinia and more generally in the Mediterranean basin.


Subject(s)
Ixodidae/microbiology , Rickettsia/classification , Rickettsia/isolation & purification , Animals , Bacterial Proteins/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , Humans , Italy , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction/methods , Rickettsia/genetics , Sequence Analysis, DNA , Sequence Homology
13.
Vet Ital ; 40(3): 329-35, 2004.
Article in English | MEDLINE | ID: mdl-20419688

ABSTRACT

Bluetongue (BT) first affected Sardinia in August 2000, spreading rapidly across the island causing more than 6,000 outbreaks and significant economic damage. Culicoides imicola Kieffer (Diptera: Ceratopogonidae) was the main vector of the disease and was also found to be the most abundant Culicoides species on Sardinia. During 2002, a field trial was conducted to evaluate the efficacy of an insecticide on local Culicoides populations in north-western Sardinia. A synthetic pyrethroid derivative (Mycrocip, ICF, Cremona, Italy) was used on two farms where outbreaks of BT had been reported; a third farm was used as control. The same treatment was repeated after 15 days. For the collection of Culicoides, two blacklight traps were placed on each farm and operated every second day for two weeks before and after insecticide treatment. Insect collections and data analyses were performed in accordance with the protocols of the Italian National Reference Centre for Exotic Diseases (CESME: Centro Studi Malattie Esotiche). For each collection, the total number of insects, Culicoides spp. and C. imicola was determined. A slight decrease in the number of Culicoides collected on treated farms was recorded for only a few days after treatment. Mycrocip played a secondary role in suppressing insect numbers, but did not reduce the number of Culicoides. Indeed, periodic variations of Culicoides population sizes correlated with significant changes in weather conditions that prevailed, including oscillating temperatures, winds and relative humidity.

14.
Vet Parasitol ; 117(1-2): 15-21, 2003 Nov 03.
Article in English | MEDLINE | ID: mdl-14597274

ABSTRACT

During the period 1999-2002, we have analyzed 9639 serum samples and 815 aborted samples (670 fetuses and 145 placenta) from 964 ovine and caprine farms distributed over all Sardinia island. After abortion notification, sera collected at random from adult animals were examined to detect simultaneously IgG and IgM antibodies specific to Toxoplasma gondii by indirect immunofluorescence assay, whereas fetuses and placenta were analyzed by a single tube nested PCR assay. Specific IgG antibodies were detected in 2048 (28.4%) sheep and 302 (12.3%) goats, specific IgM antibodies were found in 652 (9%) sheep and 139 (5.6%) goats. From a total of 2471 ovine and 362 caprine fetal samples including muscle, liver, abomasum, spleen, brain and placenta, 271 (11.1%) ovine and 23 (6.4%) caprine samples were T. gondii PCR-positive. Although T. gondii DNA was amplified from different types of tissues, placenta was the tissue with the highest detection rate. On the one hand, these results indicate that the seroprevalence of T. gondii infection in sheep and goats is relatively high, on the other PCR results demonstrate that T. gondii has a significant role in ovine and caprine abortion. Adequate management might be useful and essential to control the toxoplasmosis in the sheep and goats herds of Sardinia.


Subject(s)
Goat Diseases/epidemiology , Sheep Diseases/epidemiology , Toxoplasma/isolation & purification , Toxoplasmosis, Animal/epidemiology , Aborted Fetus/parasitology , Animals , Antibodies, Protozoan/blood , DNA, Protozoan/analysis , Female , Fluorescent Antibody Technique, Indirect/veterinary , Goat Diseases/diagnosis , Goat Diseases/parasitology , Goats , Immunoglobulin G/blood , Immunoglobulin M/blood , Italy/epidemiology , Male , Placenta/parasitology , Polymerase Chain Reaction/veterinary , Pregnancy , Pregnancy Complications, Parasitic , Prevalence , Seroepidemiologic Studies , Sheep , Sheep Diseases/diagnosis , Sheep Diseases/parasitology , Toxoplasma/genetics , Toxoplasma/immunology , Toxoplasmosis, Animal/diagnosis
15.
Vet Parasitol ; 104(4): 275-85, 2002 Apr 02.
Article in English | MEDLINE | ID: mdl-11836028

ABSTRACT

Canine infections with Leishmania infantum are important as a cause of serious disease in the dog and as a reservoir for human visceral leishmaniasis (VL). Accurate diagnosis of canine infections is essential to the veterinary community and for VL surveillance programs. A standardized ELISA using a purified recombinant antigen (rK39) specific to VL was compared to the immunofluorescent antibody test (IFAT) as the standard. The ELISA was developed, optimized and evaluated using sera from 6368 dogs. The standardized ELISA and IFAT results were highly concordant. The timing and pattern of ELISA and IFAT seroconversion in dogs followed prospectively after natural infections were very similar. Antibodies reacting with rK39 were more common in asymptomatic canine infections than reported for subclinical human VL. The rK39 ELISA is a relatively simple and rapid assay for assessing the infection status of dogs, and is an alternative to IFAT, especially when screening large numbers of samples.


Subject(s)
Antigens, Protozoan/blood , Dog Diseases/diagnosis , Enzyme-Linked Immunosorbent Assay/veterinary , Leishmania infantum/immunology , Leishmaniasis, Visceral/veterinary , Protozoan Proteins/blood , Animals , Antibodies, Protozoan/blood , Dog Diseases/parasitology , Dogs , Enzyme-Linked Immunosorbent Assay/methods , Fluorescent Antibody Technique, Indirect/veterinary , Leishmaniasis, Visceral/immunology , Leishmaniasis, Visceral/parasitology , Recombinant Proteins/blood , Reproducibility of Results , Sensitivity and Specificity
16.
Farmaco ; 53(3): 173-80, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9639865

ABSTRACT

A new series of monobactam derivatives, bearing unsubstituted or N-monosubstituted sulfamoyloxymethyl groups in position 4 was synthesized either in racemic or in optically active form. Their in vitro antibacterial activity was tested in comparison with carumonam 1a and its methoxyimino derivative 1b.


Subject(s)
Monobactams/chemical synthesis , Monobactams/pharmacology , Escherichia coli/drug effects , Molecular Structure , Pseudomonas aeruginosa/drug effects , Staphylococcus aureus/drug effects , Sulfur Compounds/chemical synthesis , Sulfur Compounds/pharmacology
17.
J Appl Microbiol ; 82(2): 177-85, 1997 Feb.
Article in English | MEDLINE | ID: mdl-12452591

ABSTRACT

A system for expression cloning of bacterial phosphatase-encoding genes has been developed, and its potential has been investigated. The system is based on histochemical screening of bacterial genomic libraries, constructed in an Escherichia coli multicopy plasmid vector, for phosphatase-producing clones using an indicator medium (named TPMG) made of Tryptose-Phosphate agar supplemented with the phosphatase substrate phenolphthalein diphosphate and the stain methyl green. To test the performance of this system, three genomic libraries were constructed from bacterial strains of different species which showed different patterns of phosphatase activity, and were screened using the TPMG medium. Following a partial screening, three different phosphatase-encoding genes (respectively encoding a class A non-specific acid phosphatase, an acid-hexose phosphatase and a non-specific alkaline phosphatase) were shotgun-cloned from the above libraries, indicating that the TPMG-based expression cloning system can be useful for rapid isolation of different bacterial phosphatase-encoding genes.


Subject(s)
Acid Phosphatase/genetics , Bacteria/enzymology , Cloning, Molecular/methods , Gene Expression Regulation, Bacterial , Genes, Bacterial , Recombinant Fusion Proteins/metabolism , Bacteria/drug effects , Bacteria/isolation & purification , Bacteriological Techniques , Coloring Agents/metabolism , Culture Media , Electrophoresis, Polyacrylamide Gel , Escherichia coli/genetics , Gene Library , Genetic Vectors , Methyl Green/metabolism , Phenolphthaleins/metabolism , Recombinant Fusion Proteins/biosynthesis , Staining and Labeling
18.
Res Microbiol ; 148(1): 11-20, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9404500

ABSTRACT

It has been suggested that, in rod-shaped bacteria, two sites for peptidoglycan assembly exist: one which is responsible for septum formation and the other, for lateral wall extension. The balance between the activities of these two sites enables bacteria to conserve their own morphology during cell growth. The effect of specifically inhibiting septum formation by different means (antibiotics and/or mutations), upon cell surface extension and macromolecular synthesis in rod-shaped and coccoid bacteria of various species, was studied. Inhibition of either cell wall expansion or macromolecular synthesis did not occur when septum formation was impaired in both rod-shaped bacteria and cocci possessing the two sites for peptidoglycan assembly, whereas a rapid and complete block of such synthesis was caused by inhibiting both sites in rod-shaped bacteria, or septum formation in cocci which possess only this site. These data indicate that bacteria possess a control mechanism that prevents macromolecular synthesis when envelope extension is inhibited.


Subject(s)
Bacteria/growth & development , Bacterial Proteins/biosynthesis , DNA, Bacterial/biosynthesis , Anti-Bacterial Agents/pharmacology , Bacteria/cytology , Bacteria/genetics , Cell Division/drug effects , Cell Wall/drug effects , Macromolecular Substances , Mutation , Peptidoglycan/pharmacology , Temperature
19.
Microb Drug Resist ; 2(2): 209-13, 1996.
Article in English | MEDLINE | ID: mdl-9158761

ABSTRACT

Penicillin resistance development in enterococci has been associated with overproduction of a low-affinity penicillin-binding protein (PBP) that is a normal component of the PBP pattern of these bacteria and is apparently able to substitute the functions of the other PBPs. In resistant mutants of Enterococcus hirae ATCC 9790 the low-affinity PBP (PBP5) overproduction was associated with a deletion in a genetic element, located 1 kb upstream of the pbp5 gene, which negatively controlled PBP5 synthesis. Hypersusceptibility to penicillin was associated with a point mutation in the pbp5 gene, which causes premature termination of translation. Structural homologies between low-affinity PBPs of the different enterococcal species have been suggested by cross-reactivity of antibodies raised against E. hirae PBP5 with PBP5 of Enterococcus faecium and Enterococcus faecalis. Acquisition of a high-level ampicillin resistance in E. faecium was associated with overproduction of PBP5, which, compared with PBP5 of moderately resistant strains, appeared to be modified in its penicillin-binding capability. The modified phenotype of PBP5 was found to be associated to some amino acid substitutions in the region between the SDN and KTG motifs. In particular, the substitution converting a polar residue (T) in a nonpolar one (A or I) could play an important role in remodeling the penicillin-binding domain and determining the decrease in penicillin affinity.


Subject(s)
Bacterial Proteins , Enterococcus/drug effects , Enterococcus/genetics , Hexosyltransferases , Penicillin Resistance/genetics , Peptidyl Transferases , Amino Acid Sequence , Base Sequence , Carrier Proteins/biosynthesis , Carrier Proteins/genetics , Molecular Sequence Data , Muramoylpentapeptide Carboxypeptidase/biosynthesis , Muramoylpentapeptide Carboxypeptidase/genetics , Penicillin-Binding Proteins
20.
Microb Drug Resist ; 2(2): 273-6, 1996.
Article in English | MEDLINE | ID: mdl-9158772

ABSTRACT

Scarce information is available on the real mechanism by which carbapenemes penetrate in Enterobacteriaceae, although a considerable amount of evidence suggests that in many species of this family the lack of certain outer membrane proteins is associated with the acquisition of resistance to these antibiotics. The existance of specific pathways for the carbapenems has never been demonstrated, although at times it has been postulated in both wild and mutant strains, on the basis of evident discordances between permeability patterns and suceptibility data. By using the Zimmerman and Rosselet technique, which requires the strain under investigation to harbor a suitable beta-lactamase, the permeability of intact Escherichia coli and Enterobacter cloacae cells to meropenem and imipenem was investigated by transferring a constructed vector carrying the carbapenem hydrolyzing CphA metallo-beta-lactamase gene into the parental strains and their porin-deficient mutants. Reduced amounts of nonspecific porins significantly reduced the penetration of both carbapenems. The virtual absence of porins caused the MICs of meropenem to increase, mostly in Enterobacter cloacae, while it did not affected the MICs of imipenem. No evidence of specific porin pathways of the type described in Pseudomonas aeruginosa was found.


Subject(s)
Bacterial Proteins , Carbapenems/metabolism , Enterobacteriaceae/metabolism , Bacterial Outer Membrane Proteins/chemistry , Bacterial Outer Membrane Proteins/metabolism , Carbapenems/chemistry , Carbapenems/pharmacology , Cell Membrane Permeability , Diffusion , Enterobacter cloacae/chemistry , Enterobacter cloacae/metabolism , Enterobacteriaceae/ultrastructure , Escherichia coli/chemistry , Escherichia coli/metabolism , Genes, Bacterial , Imipenem/pharmacology , Meropenem , Thienamycins/pharmacology , beta-Lactamases/biosynthesis , beta-Lactamases/genetics
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