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1.
Int J Immunopathol Pharmacol ; 25(2): 425-33, 2012.
Article in English | MEDLINE | ID: mdl-22697074

ABSTRACT

The aim of this study is to evaluate some inflammatory parameter changes in septic shock patients and their possible correlation with clinical outcome, in particular when continuous veno-venous hemofiltration (CVVH) treatment is required. Considering the objective difficulty in enrolling this kind of patient, a preliminary study was initiated on seventeen septic shock patients admitted to a medical and surgical ICU. The mRNA expression of Toll-like receptor (TLR)-1, TLR-2, TLR-4, TLR-5, TLR-9, TNFα, IL-8 and IL-1ß was assessed, the plasmatic concentrations of IL-18, IL-2, IL-10 and TNFα were measured on the day of sepsis diagnosis and after 72 h. In those patients who developed acute renal failure unresponsive to medical treatment and who underwent CVVH treatment the same parameters were measured every 24 h during CVVH and after completion of the treatment. On sepsis diagnosis, gene expression of TLRs was up-regulated compared to the housekeeping gene in all the patients. After 72 h, in 35% of the patients a down-regulation of these genes was found compared to day 1, but it was not associated with a reduction of cytokine serum levels or improved clinical signs, better outcome or reduced mortality. After high volume hemofiltration treatment, cytokine serum levels and TLR expression were not significantly modified. In conclusion, considering the not numerous number of cases, from our preliminary study, we cannot certainly correlate TLR over-expression in septic shock patients with severity or outcome scores.


Subject(s)
Shock, Septic/immunology , Toll-Like Receptors/blood , Acute Kidney Injury/immunology , Acute Kidney Injury/therapy , Adolescent , Aged , Aged, 80 and over , Cytokines/blood , Female , Gene Expression Regulation , Hemofiltration , Humans , Inflammation Mediators/blood , Intensive Care Units , Italy , Kinetics , Male , Middle Aged , RNA, Messenger/blood , Severity of Illness Index , Shock, Septic/diagnosis , Shock, Septic/genetics , Shock, Septic/therapy , Toll-Like Receptors/genetics , Young Adult
2.
Radiol Med ; 114(2): 331-41, 2009 Mar.
Article in English, Italian | MEDLINE | ID: mdl-19274446

ABSTRACT

PURPOSE: This study was done to assess the presence of both asymptomatic and symptomatic intervertebral disc calcifications in a large paediatric population. MATERIALS AND METHODS: We retrospectively reviewed the radiographs taken during the past 26 years in children (age 0-18 years) undergoing imaging of the spine or of other body segments in which the spine was adequately depicted, to determine possible intervertebral disc calcifications. The following clinical evaluation was extrapolated from the patients' charts: presence of spinal symptoms, history of trauma, suspected or clinically evident scoliosis, suspected or clinically evident syndromes, bone dysplasias, and pre- or postoperative chest or abdominal X-rays. RESULTS: We detected intervertebral disc calcifications in six patients only. Five calcifications were asymptomatic (one newborn baby with Patau syndrome; three patients studied to rule out scoliosis, hypochondroplasia and syndromic traits; one for dyspnoea due to sunflower seeds inhalation). Only one was symptomatic, with acute neck pain. Calcifications varied in number from one in one patient to two to five in the others. CONCLUSIONS: Apart from the calcification in the patient with cervical pain, all calcifications were asymptomatic and constituted an incidental finding (particularly those detected at the thoracic level in the patient studied for sunflower-seed inhalation). Calcification shapes were either linear or round. Our series confirms that intervertebral disc calcifications are a rare finding in childhood and should not be a source of concern: symptomatic calcifications tend to regress spontaneously within a short time with or without therapy and immobilisation, whereas asymptomatic calcifications may last for years but disappear before the age of 20 years. Only very few cases, such as those of medullary compression or severe dysphagia due to anterior herniation of cervical discs, may require surgical procedures.


Subject(s)
Calcinosis/diagnostic imaging , Intervertebral Disc/diagnostic imaging , Intervertebral Disc/pathology , Spinal Diseases/diagnostic imaging , Adolescent , Calcinosis/diagnosis , Cervical Vertebrae , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Lumbar Vertebrae , Male , Medical Records , Radiography , Retrospective Studies , Spinal Diseases/pathology , Syndrome , Thoracic Vertebrae
3.
Infect Immun ; 77(2): 733-8, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19015256

ABSTRACT

The effect of Acanthamoeba on human platelets and erythrocytes has not been fully elucidated. This paper reports that cell-free supernatants prepared from A. castellanii can activate human platelets, causing both a significant increase in the cytosolic free-calcium concentration and platelet aggregation. In addition, we demonstrated that platelet activation depends on the activity of ADP constitutively secreted into the medium by trophozoites. This study also showed that A. castellanii can affect human red blood cells, causing hemolysis, and provided evidence that hemolysis occurs in both contact-dependent and contact-independent ways; there are differences in kinetics, hemolytic activity, and calcium dependency between the contact-dependent and contact-independent mechanisms. Partial characterization of contact-independent hemolysis indicated that ADP does not affect the plasma membrane permeability of erythrocytes and that heat treatment of amoebic cell-free supernatant abolishes its hemolytic activity. These findings suggest that some heat-labile molecules released by A. castellanii trophozoites are involved in this phenomenon. Finally, our data suggest that human platelets and erythrocytes may be potential cell targets during Acanthamoeba infection.


Subject(s)
Acanthamoeba castellanii/physiology , Blood Platelets/parasitology , Erythrocytes/parasitology , Animals , Calcium/metabolism , Cell-Free System , Cells, Cultured , Humans , Time Factors
4.
Commun Agric Appl Biol Sci ; 73(2): 265-71, 2008.
Article in English | MEDLINE | ID: mdl-19226763

ABSTRACT

The most important postharvest pathogen for table grape is Botrytis cinerea (gray mold), which cause a rapid deterioration of fruit. An effective control of the disease during storage is difficult and remains an unsolved problem since no pesticide treatments are allowed by European legislation. GRAS compounds, employed with no restriction as preservatives in Europe and North America, are possible candidates to fulfil this gap. The aim of this work is to study the efficacy of Acetic Acid (AAC), used as postharvest treatment to control Botrytis cinerea on "Regina" and "Taloppo" table grapes, by Laboratory and storage tests. The activity of this compound was first assessed with laboratory tests, treating at different concentrations (0, 5, 10, 20, 50, 75 and 100 microl/L) of AAC vapors, for 15 minutes, single berries inoculated with B. cinerea. After treatments fruit was incubated at 20 degrees C for one week. The in vivo experiment took place by using the most promising AAC concentrations (50, 75 and 100 microl/L) followed by eight weeks of storage at 5 degrees C and 95% of relative humidity (RH) and four days at 20 degrees C and 85% RH (simulated shelf-life conditions). At the end of the in vivo experiment decay, weight loss and visual assessment were evaluated. Almost all treatments, after eight weeks of storage, reduced the incidence of gray mould. The best results were achieved by using 50 ppm of AAC, gaining a reduction of decay, compared to untreated "Taloppo" and "Regina" grapes of 61.0% and 41.4%, respectively. Following the simulated shelf-life period differences between treated and untreated (control) became no significant for "Taloppo" grape, while the lowest decay percentage was reached with 50 microl/L of AAC for "Regina" grape (52% of reduction if compared to control). Regarding fruit weight loss all treatments did not affect significantly this parameter that ranged between 8.2% and 11.5% after eight weeks of storage and 13.5% and 18.2% after shelf-life. At the end of storage the highest visual score was attributed to fruit treated with 50 microl/L of AAC evidencing a clear better keeping quality. During this period slight treatment damages were observed on berries following application of AAC at 75 and 100 microl/L. The reported results obtained with these experiments showed that Acetic Acid could be a promising compound to be used as alternative to SO2 in keeping grapes quality and controlling decay during storage.


Subject(s)
Acetic Acid/pharmacology , Botrytis/drug effects , Food Preservatives/pharmacology , Fungicides, Industrial/pharmacology , Vitis/microbiology , Botrytis/growth & development , Consumer Product Safety , Dose-Response Relationship, Drug , Food Handling/methods , Food Microbiology , Food Preservation/methods , Humidity , Temperature , Time Factors
5.
Trends Parasitol ; 23(11): 540-7, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17962075

ABSTRACT

Surface proteins of mucosal microbial pathogens play multiple and essential roles in initiating and sustaining the colonization of the heavily defended mucosa. The protist Trichomonas vaginalis is one of the most common human sexually transmitted pathogens that colonize the urogenital mucosa. However, little is known about its surface proteins. The recently completed draft genome sequence of T. vaginalis provides an invaluable resource to guide molecular and cellular characterization of surface proteins and to investigate their role in pathogenicity. Here, we review the existing data on T. vaginalis surface proteins and summarize some of the main findings from the recent in silico characterization of its candidate surface proteins.


Subject(s)
Genome, Protozoan , Membrane Proteins/genetics , Protozoan Proteins/genetics , Trichomonas vaginalis/genetics , Amino Acid Sequence , Animals , Molecular Sequence Data , Proteome/genetics , Sequence Alignment , Trichomonas vaginalis/metabolism
6.
Radiol Med ; 111(6): 855-62, 2006 Sep.
Article in English, Italian | MEDLINE | ID: mdl-16896554

ABSTRACT

PURPOSE: The aim of this study was to describe the radiological features of simple or dilated (syringocele) Cowper's ducts in a large paediatric population. MATERIALS AND METHODS: Voiding cystourethrography procedures performed during the past 24 years were evaluated taking into special account urethral morphology. The procedures were performed to study all sorts of possible urinary affections. RESULTS: A total of 1,676 male children (age: newborn to 18 years) underwent 2,340 voiding cystourethrographies. Opacification of Cowper's ducts was observed in nine children (0.53%) - in six (0.35%) as a thin, radiopaque image running parallel to the inferior edge of the membranous-bulbar urethra and in three (0.18%) as a dilated structure (syringocele); this was a source of significant voiding problems. CONCLUSIONS: Opacification of Cowper's ducts - even if rare - has to be recognised as a possible anatomical finding during voiding cystourethrography in paediatric patients. An accessory finding devoid of pathological meaning in most cases, it can, however, be a possible cause of voiding disorders in some instances.


Subject(s)
Bulbourethral Glands/diagnostic imaging , Adolescent , Child , Child, Preschool , Dilatation, Pathologic , Humans , Infant , Infant, Newborn , Male , Radiography
7.
Radiol Med ; 111(3): 432-9, 2006 Apr.
Article in English, Italian | MEDLINE | ID: mdl-16683088

ABSTRACT

PURPOSE: The purpose of this study is to report radiological findings and evaluate the frequency with which Kirner's deformity is found in a large paediatric population. MATERIALS AND METHODS: We reviewed X-ray films of the hands taken over the past 23.5 years in order to assess not only bone age but all sorts of bone abnormalities (trauma, haematological disorders, bone syndromes and dysplasias, dysmorphic features, rheumatic disorders, etc.) to retrospectively evaluate all those presenting Kirner's deformity. RESULTS: Among the 16,326 patients who underwent X-ray study of the hands, nine (six males and three females, 0.055% of the total) presented the typical radiological features of Kirner's deformity; no patient had a family history of the disorder except for one, in whom the suspicion of familiarity could not be verified radiologically. The diagnosis of Kirner's deformity was straightforward in most cases. In one case, a girl affected by Turner's syndrome, the abnormality was suspected, and its appearance, development and evolution was followed over 10 years. CONCLUSIONS: Although rare, as also shown by our study, Kirner's deformity must be recognised and properly diagnosed in order to spare the subject unnecessary surgical procedures.


Subject(s)
Fingers/abnormalities , Adolescent , Child , Child, Preschool , Female , Fingers/diagnostic imaging , Follow-Up Studies , Humans , Male , Nails, Malformed , Radiography , Retrospective Studies , Turner Syndrome/complications
8.
Eukaryot Cell ; 5(4): 665-71, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16607014

ABSTRACT

This work was undertaken to determine whether Acanthamoeba could play a role in the survival and transmission of coxsackieviruses and focused on in vitro interactions between Acanthamoeba castellanii and coxsackie B3 viruses (CVB-3). Residual virus titer evaluations and immunofluorescence experiments revealed a remarkable CVB-3 adsorption on amoeba surfaces and accumulation inside cells. The survival of viruses was independent of the dynamics of amoeba replication and encystment. In addition, our results indicated that virus-infected amoebas can release infectious viruses during interaction with human macrophages. On the basis of these data, Acanthamoeba appears to be a potential promoter of the survival of coxsackieviruses and their transmission to human hosts.


Subject(s)
Acanthamoeba castellanii/physiology , Acanthamoeba castellanii/virology , Disease Vectors , Enterovirus/physiology , Receptors, Virus/physiology , Virus Replication , Acanthamoeba castellanii/growth & development , Animals , Cell Membrane/virology , Fluorescent Antibody Technique , Humans , Macrophages/ultrastructure , Macrophages/virology , Microbial Viability , Time Factors
9.
Commun Agric Appl Biol Sci ; 70(3): 339-43, 2005.
Article in English | MEDLINE | ID: mdl-16637198

ABSTRACT

The trade of fresh fig fruit is restricted by its high perishability and numerous attempts have been done to extend the postharvest life. The main difficulties can be found in the fast ripening and the easiness of pathogen spread. Although the ripening can be slowed by low storage temperatures (close to 0 degrees C) the control of pathogens remains still unsolved since no pesticide treatments are allowed. Generally Recognized As Save Compounds (G.R.A.S.) are possible candidates to fulfil this void. Sodium carbonate (SC) solutions (0.5, 1, 2 and 3%) and acetic acid (AAC) vapours (25, 50 and 100 ppm) have been used as postharvest treatments to control Botrytis cinerea on black (Craxiou de Porcu) and white (Rampelina) fig varieties. Fruit was subsequently stored at 2 or 8 degrees C and 90% relative humidity for two weeks. At the end of the experiment decay, weight loss, pH, acidity, total soluble solids and visual assessment were performed. SC treatment at 1% reduced significantly the decay while, lower and higher concentrations did not. Between the two studied varieties the lowest decay percentage (9.8%) was found for the Craxiou de Porcu. Using AAC a good efficacy was achieved only with 100 ppm, this treatment decrease to 2.4% the incidence of decay irrespective to storage temperature. Lower concentrations were lesser effective and the efficacy was strictly dependent on the storage temperature, being higher at 2 degrees C. No treatment damages were observed following SC or AAC applications. Regarding fruit weight loss all treatments did not affect this parameter that was 10.1% and 16.9% at 2 and 8 degrees C, respectively. Chemical analyses performed at the end of the storage period did not evidenced differences among the treatments and slight ones if compared to initial values. Visual score of the fruit at the end of storage evidenced a better keeping quality for Craxiou de Porcu especially when stored at 2 degrees C. Both G.R.A.S. compounds are promising, but in the reported experiments AAC was the most effective.


Subject(s)
Botrytis/growth & development , Ficus , Food Handling/methods , Food Preservation/methods , Food Preservatives/pharmacology , Acetic Acid/pharmacology , Botrytis/drug effects , Carbonates/pharmacology , Cold Temperature , Consumer Product Safety , Dose-Response Relationship, Drug , Food Microbiology , Humidity , Time Factors
10.
Antimicrob Agents Chemother ; 48(12): 4520-7, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15561820

ABSTRACT

The present study demonstrates the in vitro effectiveness of the macrolide rokitamycin and the phenothiazine compound chlorpromazine against Acanthamoeba castellanii. Growth curve evaluations revealed that both drugs inhibit trophozoite growth in dose- and time-dependent ways. The effects of both drugs when they were used at the MICs at which 100% of isolates are inhibited were amoebistatic, but at higher doses they were amoebicidal as well as cysticidal. Experiments showed that when rokitamycin was associated with chlorpromazine or amphotericin B, rokitamycin enhanced their activities. Furthermore, low doses of rokitamycin and chlorpromazine, alone or in combination, blocked the cytopathic effect of A. castellanii against WKD cells derived from the human cornea. These results may have important significance in the development of new anti-Acanthamoeba compounds.


Subject(s)
Acanthamoeba/drug effects , Acanthamoeba/growth & development , Amebiasis/drug therapy , Amebicides/pharmacology , Chlorpromazine/pharmacology , Miocamycin/analogs & derivatives , Miocamycin/pharmacology , Amebiasis/parasitology , Amebiasis/pathology , Animals , Cells, Cultured , Cornea/cytology , Cornea/parasitology , Cornea/pathology , Drug Synergism , Humans
11.
Cell Mol Life Sci ; 61(5): 618-623, 2004 Mar.
Article in English | MEDLINE | ID: mdl-15004700

ABSTRACT

Besides possessing many physiological roles, nitric oxide (NO) produced by the immune system in infectious diseases has antimicrobial effects. Trichomoniasis, the most widespread non-viral sexually transmitted disease caused by the microaerophilic protist Trichomonas vaginalis, often evolves into a chronic infection, with the parasite able to survive in the microaerobic, NO-enriched vaginal environment. We relate this property to the finding that T. vaginalis degrades NO under anaerobic conditions, as assessed amperometrically. This activity, which is maximal (133 +/- 41 nmol NO/10(8) cells per minute at 20 degrees C) at low NO concentrations (< or = 1.2 microM), was found to be: (i) NADH dependent, (ii) cyanide insensitive and (iii) inhibited by O(2). These features are consistent with those of the Escherichia coli A-type flavoprotein (ATF), recently discovered to be endowed with NO reductase activity. Using antibodies against the ATF from E. coli, a protein band was immunodetected in the parasite grown in a standard medium. If confirmed, the expression of an ATF in eukaryotes suggests that the genes coding for ATFs were transferred during evolution from anaerobic Prokarya to pathogenic protists, to increase their fitness for the microaerobic, parasitic life style. Thus the demonstration of an ATF in T. vaginalis would appear relevant to both pathology and evolutionary biology. Interestingly, genomic analysis has recently demonstrated that Giardia intestinalis and other pathogenic protists have genes coding for ATFs.


Subject(s)
Flavoproteins/metabolism , Nitric Oxide/metabolism , Trichomonas vaginalis/metabolism , Animals , Flavoproteins/immunology , Immunoblotting , Oxygen/metabolism
12.
Infect Immun ; 70(8): 4424-32, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12117953

ABSTRACT

Monocytes/macrophages are thought to be involved in Acanthamoeba infections. The aim of this work was to study whether soluble metabolites (ADP and other compounds) released by Acanthamoeba castellanii trophozoites could induce morphological and biochemical changes in human monocytic cells in vitro. We demonstrate here that ADP constitutively released in the medium by A. castellanii, interacting with specific P2y(2) purinoceptors expressed on the monocytic cell membrane, caused a biphasic rise in [Ca(2+)](i), morphological changes characteristics of cells undergoing apoptosis, caspase-3 activation, and secretion of tumor necrosis factor alpha (TNF-alpha). The same results were found in monocytes exposed to purified ADP. Cell damage and TNF-alpha release induced by amoebic ADP were blocked by the P2y(2) inhibitor suramin. Other metabolites contained in amoebic cell-free supernatants, with molecular masses of, respectively, >30 kDa and between 30 and 10 kDa, also caused morphological modifications and activation of intracellular caspase-3, characteristics of programmed cell death. Nevertheless, mechanisms by which these molecules trigger cell damage appeared to differ from that of ADP. In addition, other amoebic thermolable metabolites with molecular masses of <10 kDa caused the secretion of interleukin-1beta. These findings suggest that pathogenic free-living A. castellanii by release of ADP and other metabolites lead to human monocytic cell death through apoptosis and stimulate the secretion of proinflammatory cytokines.


Subject(s)
Acanthamoeba/metabolism , Adenosine Diphosphate/metabolism , Apoptosis , Interleukin-1/metabolism , Interleukin-6/metabolism , Tumor Necrosis Factor-alpha/metabolism , Animals , Calcium/metabolism , Cell Line , Cell Membrane Permeability , Culture Media, Conditioned , Cytosol/metabolism , Humans , Interleukin-12/metabolism , Monocytes/cytology
13.
Exp Cell Res ; 266(2): 270-8, 2001 Jun 10.
Article in English | MEDLINE | ID: mdl-11399055

ABSTRACT

Using the monoclonal antibody MA-01, a new 210-kDa microtubule-interacting protein was identified in Leishmania promastigotes by immunoblotting and by immunoprecipitation. The protein was thermostable and was located on microtubules prepared by taxol-driven polymerization in vitro. On fixed cells the antibody gave specific staining of flagellum, flagellar pocket, and mitotic spindle. Subpellicular microtubules were basically not decorated but posterior poles of the cells were labeled in a cell-cycle-dependent manner. In anterior and posterior poles of cells the 210-kDa protein codistributed with the 57-kDa protein, immunodetected with anti-vimentin antibody, that was located only on cell poles. Immunolocalization of the 57-kDa protein was most prominent in dividing cells. The presented data suggest that the 210-kDa protein is a newly identified microtubule-interacting protein of Leishmania that could be involved in anchoring the microtubules in posterior poles of these cells. The striking codistribution of the microtubule-interacting protein and the 57-kDa protein in protozoa is described for the first time.


Subject(s)
Cytoskeletal Proteins/analysis , Leishmania/chemistry , Microtubules/chemistry , Animals , Antibodies, Monoclonal/immunology , Cell Cycle , Cell Division , Cells, Cultured , Cytoskeletal Proteins/immunology , Flagella/chemistry , Interphase , Leishmania/cytology , Leishmania tropica/chemistry , Spindle Apparatus/chemistry , Temperature , Vimentin/analysis , Vimentin/immunology
14.
Infect Immun ; 69(6): 4134-40, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11349088

ABSTRACT

The role played by soluble molecules that may participate in acanthamoebal cytopathogenicity has yet to be fully characterized. We demonstrate here that Acanthamoeba castellanii trophozoites constitutively release ADP in the medium. Cell-free supernatants prepared from A. castellanii, by interaction with specific P(2y2) purinoceptors expressed on the Wish cell membrane, caused a biphasic rise in [Ca(2+)](i), extensive cell membrane blebbing, cytoskeletal disorganization, and the breakdown of nuclei. Cell damage induced by amoebic supernatants was blocked by the P(2y2) inhibitor Suramin. The same results were found in Wish cells exposed to purified ADP. These findings suggest that pathogenic free-living A. castellanii may have a cytopathic effect on human epithelial cells through ADP release, by a process that begins with a rise of cytosolic free-calcium concentration, and culminates in apoptosis.


Subject(s)
Acanthamoeba/pathogenicity , Adenosine Diphosphate/metabolism , Apoptosis/physiology , Calcium/metabolism , Cytosol/metabolism , Acanthamoeba/growth & development , Acanthamoeba/metabolism , Actins/metabolism , Animals , Cell Line , Epithelial Cells , Humans
15.
Epidemiol Infect ; 126(1): 103-9, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11293668

ABSTRACT

Enzyme immunoassay (EIA) was used to detect antibodies to Trichomonas vaginalis in sera from Zimbabwe. The EIA showed a sensitivity of 95 and 94% when compared with vaginal swab culture among women attending a family planning clinic (FPC) and female commercial sex workers (CSW) respectively. The specificity was 85 and 77% in the two groups. Culture-negative FPC women were sub-divided into high risk or low risk of exposure to trichomoniasis. The seroprevalence was 10% (6/61) among low risk women, 21% (10/48) among high risk women and 23% (9/39) among culture negative CSW. The EIA was positive in 46% (18/39) men with genital discharge but only 5% (2/37) healthy blood donors. None of 31 sera from prepubescent children was positive. The EIA may be useful for community surveys of trichomoniasis. Because T. vaginalis is a common sexually transmitted disease, the test may indicate behaviour that increases the risk of STD transmission.


Subject(s)
Antibodies, Protozoan/analysis , Sexual Behavior , Trichomonas Infections/diagnosis , Urogenital System/parasitology , Adolescent , Adult , Animals , Biomarkers , Child , Child, Preschool , Female , Humans , Immunoenzyme Techniques/methods , Infant , Male , Risk Factors , Sensitivity and Specificity , Seroepidemiologic Studies , Sex Work , Trichomonas Infections/transmission , Trichomonas vaginalis/isolation & purification , Vagina/parasitology , Zimbabwe
16.
Arch Microbiol ; 175(1): 70-4, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11271423

ABSTRACT

We recently reported that most Trichomonas vaginalis isolates cultured in vitro are infected by Mycoplasma hominis. In this work, we have characterized some aspects of the relationships between the two microorganisms. PCR, cultivation, and immunological methods revealed that the number of M. hominis organisms carried by T. vaginalis in culture varied from isolate to isolate, suggesting a specific multiplicity of infection. Moreover, infected T. vaginalis isolates were able to pass bacteria not only to M. hominis-free protozoa, but also to human-derived epithelial cells. The in vitro transmission of the bacterium from T. vaginalis to both uninfected parasite isolates and human epithelial cells suggests a role for T. vaginalis as a carrier of the M. hominis infection in vivo.


Subject(s)
Mycoplasma hominis/pathogenicity , Trichomonas vaginalis/microbiology , Animals , Antigens, Bacterial/analysis , DNA, Bacterial/analysis , Disease Transmission, Infectious , Epithelial Cells/microbiology , Fluorescent Antibody Technique , HeLa Cells , Humans , Immunoblotting , In Vitro Techniques , Mycoplasma Infections/transmission , Mycoplasma hominis/immunology , Polymerase Chain Reaction , Sexually Transmitted Diseases/microbiology , Sexually Transmitted Diseases/transmission , Symbiosis
17.
New Microbiol ; 24(1): 77-83, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11209846

ABSTRACT

Diarrheagenic E. coli comprise a diverse group of microorganisms responsible for gastrointestinal diseases in humans. On the basis of their virulence traits they are distinguished from the non-pathogenic E. coli and classified in several categories. Molecular methods represent the most reliable techniques for distinguishing pathogenic from non-pathogenic E. coli and characterising their pathogenic features. In this paper we report the development of a set of three multiplex PCR assays for the simultaneous and rapid identification of diarrheagenic E. coli belonging to ETEC, EPEC, EHEC and EIEC groups. Assay 1 utilizes primer pairs specific for genes coding for ST and LT toxins of ETEC, and for the E. coli beta-glucuronidase (uidA); assay 2 detects the presence of the eae and bfpA genes of EPEC, and assay 3 recognizes stx1 and stx2 of EHEC, and ial of EIEC. This technique has been validated on 190 E. coli isolated in Angola, Italy and Mozambique from feces of children with diarrhea. Results obtained with the set of multiplex PCR demonstrated 100% accordance with those obtained for the same isolates by PCR on single target genes. The proposed set of multiplex PCRs is the first reported assay that allows the simultaneous characterization of the four categories of diarrheagenic E. coli.


Subject(s)
Diarrhea/microbiology , Escherichia coli Infections/microbiology , Escherichia coli/pathogenicity , Polymerase Chain Reaction/methods , Angola , Child , DNA Primers/chemistry , DNA, Bacterial/chemistry , DNA, Bacterial/isolation & purification , Escherichia coli/classification , Escherichia coli/genetics , Feces/microbiology , Humans , Italy , Mozambique , Virulence
19.
Microb Pathog ; 29(2): 93-100, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10906264

ABSTRACT

Mycobacterium avium is a facultative intracellular microorganism, able to survive and multiply within mammalian macrophages by circumventing antimicrobial mechanisms. In this study we hypothesize that pre-existing M. avium infection could result in macrophage superinfections by other microorganisms. We found that 24 h after ingestion of M. avium at a low multiplicity of infection, macrophages are unable to efficiently produce superoxide anions when over-stimulated with phorbol esters, and that the generation of oxidative burst is only partially restored 72 h after bacteria ingestion. We also demonstrate that intracellular killing of Cryptococcus neoformans is markedly impaired in human macrophages that have previously ingested M. avium (but not other bacteria such as Escherichia coli). This inhibitory effect is observed with live mycobacteria, but not when heat-inactivated bacteria are ingested. In contrast, when Candida albicans is given to macrophages instead of C. neoformans, an enhancement of intracellular killing is observed, suggesting that cytocidal mechanisms other than respiratory burst are involved in the anti- Candidacidal activity of macrophages.


Subject(s)
Candida albicans/immunology , Cryptococcus neoformans/immunology , Macrophages/immunology , Macrophages/microbiology , Mycobacterium avium/immunology , Humans , Macrophages/metabolism , Monocytes/metabolism , Phagocytosis , Superoxides/metabolism
20.
Infect Immun ; 68(7): 4358-60, 2000 Jul.
Article in English | MEDLINE | ID: mdl-10858260

ABSTRACT

Adhesion of Trichomonas vaginalis is believed to be dependent on four adhesion proteins, which are thought to bind to vaginal epithelial cells in a specific manner with a ligand-receptor type of interaction. However, the specific receptors on the host cell have not yet been identified. In this work, the ability of the T. vaginalis adhesins to bind to cells of different histologic derivations and from different species has been studied. HeLa, CHO, and Vero cell lines; erythrocytes from different species; and a prokaryote without a cell wall, Mycoplasma hominis, were employed in order to investigate the cell specificity of the T. vaginalis adhesins. We observed that the T. vaginalis adhesins are able to bind to the different cell types to the same extent, suggesting that the host and tissue specificity of T. vaginalis adhesion should not be due to specificity of the parasite adhesins. Our results suggest that the data published to date on the subject are probably artifactual and that the experiments reported in the literature are not appropriate for identification of protozoan adhesins.


Subject(s)
Protozoan Proteins/physiology , Trichomonas vaginalis/physiology , Trichomonas vaginalis/pathogenicity , Animals , CHO Cells , Cell Adhesion/physiology , Chlorocebus aethiops , Cricetinae , Erythrocytes/parasitology , Female , HeLa Cells , Humans , Mycoplasma , Protein Binding , Vero Cells
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