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1.
J Chemother ; 24(2): 93-6, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22546764

ABSTRACT

The rapid emergence of KPC-producing Klebsiella pneumoniae has become a serious problem in health-care settings, increasing in frequency worldwide. These infections are worrisome, since the antimicrobial treatment options for infections due to multidrug-resistant strains are very limited, and outbreaks must be rapidly detected and controlled. A semi-automated, repetitive-sequence-based PCR (rep-PCR) instrument (DiversiLab system) was evaluated in comparison with the pulse-field gel electrophoresis (PFGE) and multilocus sequence typing to investigate the outbreak of KPC-producing K. pneumoniae in a surgery unit at the University Hospital of Verona, Italy, as a rapid method for outbreak investigations. A selection of seven epidemiologically related K. pneumoniae showing resistance to carbapenem and three epidemiologically unrelated K. pneumoniae isolates were collected from patient with hospital-acquired infection. Among the epidemiologically related isolates, PFGE and Rep-PCR identified a unique pattern with more than 90% of homology. The concordance between DiversiLab and PFGE results confirmed the usefulness of rapid molecular techniques to investigate outbreaks due to multidrug-resistant bacteria. Moreover, this result could meet the international need for a harmonised typing tool, allowing the implementation of strict control measures to prevent dissemination of these organisms in health-care settings.


Subject(s)
Abdomen/microbiology , Abdomen/surgery , Bacterial Proteins/genetics , Disease Outbreaks , Klebsiella Infections/diagnosis , Klebsiella Infections/microbiology , Klebsiella pneumoniae/isolation & purification , beta-Lactamases/genetics , Bacterial Typing Techniques , DNA, Bacterial/genetics , Electrophoresis, Gel, Pulsed-Field , Hospitals, University , Humans , Italy , Klebsiella Infections/genetics , Klebsiella pneumoniae/enzymology , Klebsiella pneumoniae/genetics , Microbial Sensitivity Tests , Multilocus Sequence Typing , Polymerase Chain Reaction , Repetitive Sequences, Nucleic Acid/genetics
2.
Br J Sports Med ; 41(8): 506-9; discussion 509, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17341588

ABSTRACT

OBJECTIVE: To assess which of the equations used to estimate mechanical power output for a wide aerobic range of exercise intensities gives the closest value to that measured with the SRM training system. METHODS: Thirty four triathletes and endurance cyclists of both sexes (mean (SD) age 24 (5) years, height 176.3 (6.6) cm, weight 69.4 (7.6) kg and Vo(2)max 61.5 (5.9) ml/kg/min) performed three incremental tests, one in the laboratory and two in the velodrome. The mean mechanical power output measured with the SRM training system in the velodrome tests corresponding to each stage of the tests was compared with the values theoretically estimated using the nine most referenced equations in literature (Whitt (Ergonomics 1971;14:419-24); Di Prampero et al (J Appl Physiol 1979;47:201-6); Whitt and Wilson (Bicycling science. Cambridge: MIT Press, 1982); Kyle (Racing with the sun. Philadelphia: Society of Automotive Engineers, 1991:43-50); Menard (First International Congress on Science and Cycling Skills, Malaga, 1992); Olds et al (J Appl Physiol 1995;78:1596-611; J Appl Physiol 1993;75:730-7); Broker (USOC Sport Science and Technology Report 1-24, 1994); Candau et al (Med Sci Sports Exerc 1999;31:1441-7)). This comparison was made using the mean squared error of prediction, the systematic error and the random error. RESULTS: The equations of Candau et al, Di Prampero et al, Olds et al (J Appl Physiol 1993;75:730-7) and Whitt gave a moderate mean squared error of prediction (12.7%, 21.6%, 13.2% and 16.5%, respectively) and a low random error (0.5%, 0.6%, 0.7% and 0.8%, respectively). CONCLUSIONS: The equations of Candau et al and Di Prampero et al give the best estimate of mechanical power output when compared with measurements obtained with the SRM training system.


Subject(s)
Anaerobic Threshold/physiology , Bicycling/physiology , Exercise Tolerance/physiology , Oxygen Consumption/physiology , Adult , Anthropometry , Exercise Test , Female , Humans , Male , Models, Theoretical , Musculoskeletal Physiological Phenomena , Probability , Sensitivity and Specificity
3.
Eur J Clin Microbiol Infect Dis ; 25(12): 773-81, 2006 Dec.
Article in English | MEDLINE | ID: mdl-17089093

ABSTRACT

The aim of the present study was to characterize clinical isolates of Staphylococcus epidermidis, one of the bacterial species most often implicated in foreign-body-associated infections, for their ability to form biofilms and for the presence of mecA and IS256 element. Sixty-seven Staphylococcus epidermidis clinical isolates, obtained from implantable medical devices, were investigated. Overall, 70% of the strains were positive for ica operon genes, 85% possessed atlE, and 46% contained aap. In 89% of the population, the Congo red agar test confirmed the correlation between the presence of ica genes and slime expression. Almost all of the strains could be classified as biofilm producers by both the crystal violet assay and microscopy. The bacterial population studied showed a very high frequency of strains positive for mecA as well as for the IS256 element. Although well-structured biofilms have been previously observed only in those strains possessing genes belonging to the ica operon, this study demonstrates that strains lacking specific biofilm-formation determinants can be isolated from catheters and can form a biofilm in vitro. Hence, different and yet-to-be identified factors may work together in the formation and organization of complex staphylococcal microbial communities and sustain infections associated with implanted medical devices.


Subject(s)
Biofilms , Catheters, Indwelling/microbiology , DNA Transposable Elements/genetics , Drug Resistance, Bacterial/genetics , Staphylococcus epidermidis/genetics , Staphylococcus epidermidis/physiology , Anti-Bacterial Agents/pharmacology , Catheterization, Central Venous , Drug Resistance, Bacterial/drug effects , Humans , Microscopy, Confocal , Oxacillin/pharmacology , Phylogeny
4.
Mol Reprod Dev ; 73(1): 1-8, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16177984

ABSTRACT

Proopiomelanocortin (POMC) is a precursor protein that contains the sequences of several bioactive peptides including adrenocorticotropin (ACTH), beta-endorphin (beta-EP), and melanocyte-stimulating-hormone (MSH). POMC is synthesized in the pituitary gland, brain, and many peripheral tissues. Immunoreactive POMC-derived peptides as well as POMC-like mRNA have been evidenced in several nonpituitary tissues, thus suggesting that POMC is actively synthesized by these tissues. The present study was aimed at evaluating if also in the case of stallion POMC-derived peptide, beta-EP, is produced locally in the testis, thus playing effects in a paracrine/autocrine fashion. To investigate this hypothesis the POMC gene expression was analyzed using 3' RACE-PCR and Northern Blot approaches in the testis and epididimys of stallion; moreover, immunocytochemical localization for beta-EP was also performed through confocal laser microscopy. The immunofluorescence results showed a positive beta-EP reaction not only in cellular nest of pituitary but also in the testis and genital tract of stallion, which function could be related with sperm mobility. Such role seem not to be no dependent on the peptide synthesized locally, because the molecular biology approach demonstrated the presence of POMC transcript in the pituitary only. In fact the Northern Blot analysis showed the presence of a single POMC transcript in the pituitary while no signal was detected in the testis and epididimys. The same results were obtained by applied 3' RACE-PCR analysis. In conclusion, opioid-derived peptide beta-EP is present in the genital tract of stallion, but is not locally produced as in other mammalian, and nonmammalian models; its possible biological function at testicular level could be linked to a long-loop feed-back mechanisms.


Subject(s)
Epididymis/metabolism , Horses/metabolism , Pituitary Gland/metabolism , Pro-Opiomelanocortin/biosynthesis , Pro-Opiomelanocortin/genetics , Testis/metabolism , beta-Endorphin/metabolism , Animals , Base Sequence , Blotting, Northern , Humans , Male , Microscopy, Confocal , Microscopy, Fluorescence , Molecular Sequence Data , Polymerase Chain Reaction
5.
J Exp Biol ; 204(Pt 11): 1901-7, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11441032

ABSTRACT

We recently discovered, in mating-competent Paramecium primaurelia, the presence of functionally related molecules of the cholinergic system: the neurotransmitter acetylcholine (ACh), both its nicotinic and muscarinic receptors and its lytic enzyme acetylcholinesterase (AChE). Our results on the inhibition of mating-cell pairing in vivo in mating-competent cells treated with cholinomimetic drugs support the hypothesis that the cholinergic system plays a role in cell-to-cell adhesion. To investigate the possible function of the signal molecule ACh in conjugation in P. primaurelia, we attempted to detect the intracellular sites of ACh synthesis by localizing the ACh biosynthetic enzyme choline acetyltransferase (ChAT). Using immunocytochemical and histochemical methods, we have demonstrated the presence and activity of ChAT principally on the surface membrane of mating-competent cells and of mature but non-mating-competent cells. No evidence for ChAT activity was found in immature cells. Immunoblot analysis revealed the presence of immunoreactive bands, ranging in molecular mass from 42 to 133 kDa, as reported for ChAT isolated from higher organisms. In vivo experiments showed that inhibition of ChAT activity by Congo Red, known to be a potent competitive inhibitor of acetyl coenzyme A, did not affect mating-cell pairing. Conversely, inhibition of AChE with BW 284c51 or eserine, which block enzyme activity by reacting with a specific serine within the catalytic centre, significantly inhibited mating-cell pairing. Our results suggest that ACh has a negative modulating effect on conjugation in P. primaurelia.


Subject(s)
Acetylcholine/biosynthesis , Paramecium/growth & development , Paramecium/metabolism , Acetylcholinesterase/metabolism , Animals , Cell Adhesion , Choline O-Acetyltransferase/metabolism , Cholinesterase Inhibitors/pharmacology , Immunohistochemistry , Paramecium/drug effects , Physostigmine/pharmacology , Reproduction/physiology , Signal Transduction
6.
Biochim Biophys Acta ; 1505(2-3): 226-37, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11334787

ABSTRACT

Previous literature reports have demonstrated that nucleated trout erythrocytes in condition of oxidative stress are subjected to DNA and membrane damage, and inactivation of glutathione peroxidase. The present study was undertaken to investigate if mitochondrial membrane potential in stressed conditions was also influenced. Density-separated trout erythrocyte fractions, obtained using a discontinuous Percoll gradient, were submitted to stress conditions and the mitochondrial membrane potential was determined by means of cytofluorimetric analysis after incubation of each subfraction with JC-1, a mitochondrial specific fluorescent probe. The results clearly show that the mitochondrial membrane potential decreased significantly in all erythrocyte fractions, also if the oxidative effect on mitochondria is more severe with increased density (age) of the cell. Ebselen was very effective in preventing mitochondrial depolarization in young as well as in old erythrocytes.


Subject(s)
Erythrocytes/chemistry , Intracellular Membranes/chemistry , Mitochondria/chemistry , Animals , Antioxidants/pharmacology , Azoles/pharmacology , Benzimidazoles , Carbocyanines , Cellular Senescence , Chromans/pharmacology , Cyclic N-Oxides/pharmacology , Flow Cytometry , Fluorescent Dyes , Free Radicals/analysis , In Vitro Techniques , Isoindoles , Membrane Potentials , Microscopy, Confocal , Molecular Structure , Organoselenium Compounds/pharmacology , Oxidative Stress/drug effects , Reactive Oxygen Species , Trout
7.
Eur J Epidemiol ; 16(5): 433-7, 2000 May.
Article in English | MEDLINE | ID: mdl-10997830

ABSTRACT

Cytomegalovirus (CMV) infection was one of the most common opportunistic infections in AIDS patients, leading to blindness or life-threatening disease in about 40% of patients in the later stages of AIDS before highly active antiretroviral therapy (HAART). In a retrospective multicenter study we investigated the incidence of CMV retinitis and organ involvement in Northern Italy before (1995 and 1996) and after the introduction of HAART (1997 and 1998) as well as the data regarding CMV antigenemia. We found a sharp drop in the incidence of CMV disease in AIDS patients as well as a decline in the incidence of relapses of CMV-disease after the widespread introduction of HAART. Moreover, there was a decrease in the incidence of antigenemia-positive cases in AIDS patients in the era of HAART and the median CMV viral load was significantly higher in patients who didn't receive HAART than in patients who received HAART (p = 0.001, t test).


Subject(s)
AIDS-Related Opportunistic Infections/drug therapy , AIDS-Related Opportunistic Infections/epidemiology , Antigens, Viral/analysis , Antiretroviral Therapy, Highly Active , Cytomegalovirus Infections/drug therapy , Cytomegalovirus Infections/epidemiology , Cytomegalovirus/immunology , AIDS-Related Opportunistic Infections/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Cohort Studies , Cytomegalovirus Infections/diagnosis , Cytomegalovirus Retinitis/diagnosis , Cytomegalovirus Retinitis/drug therapy , Cytomegalovirus Retinitis/epidemiology , Data Interpretation, Statistical , Follow-Up Studies , Humans , Italy/epidemiology , Middle Aged , Neutrophils , Recurrence , Retrospective Studies , Time Factors
8.
AIDS ; 14(5): 553-9, 2000 Mar 31.
Article in English | MEDLINE | ID: mdl-10780718

ABSTRACT

OBJECTIVE: To evaluate the cancer risk in southern European men with, or at risk of, HIV infection. DESIGN: An analysis of longitudinal data to assess time-dependent rare events. METHODS: Data from a cohort of HIV seroconverters, and from two hospital-based HIV seroprevalent cohorts were combined and analysed. The number of cancer cases observed was compared with the expected number, obtained from cancer incidence rates among men in the general population. Age-standardized incidence ratios (SIR) and their 95% confidence intervals (CI) were computed. RESULTS: A total of 19,609 person-years of observation were accumulated among HIV-positive men, and 7957 person-years among HIV-negative men. Among HIV-positive men, statistically significant increased SIR were seen for Hodgkin's disease (HD) (SIR = 8.7), liver cancer (SIR = 11.0), and cancer of the salivary glands (SIR = 33.6). An excess of lung cancer was seen among intravenous drug users (IDU), but not among homosexual men. When the risk of all non-AIDS-defining cancers was considered, HIV-positive men had a nearly twofold excess (95% CI: 1.2-2.8). A risk of similar magnitude emerged among HIV-negative IDU (95% CI: 1.0-4.5), largely attributable to lung cancer and HD. CONCLUSION: These findings confirm that HIV infection increases the risk of HD, whereas they suggest that the risk of hepatocellular carcinoma may also be enhanced by HIV infection. The observation of an elevated risk of lung cancer in both HIV-positive and HIV-negative IDU points to personal behaviours unrelated to HIV infection.


Subject(s)
HIV Infections/complications , Neoplasms/complications , Adult , Cohort Studies , France/epidemiology , HIV Infections/epidemiology , Hematologic Neoplasms/epidemiology , Hodgkin Disease/epidemiology , Homosexuality, Male , Humans , Incidence , Italy/epidemiology , Liver Neoplasms/epidemiology , Lung Neoplasms/epidemiology , Male , Middle Aged , Neoplasms/epidemiology , Risk Factors , Salivary Gland Neoplasms/epidemiology , Substance Abuse, Intravenous
9.
Biochim Biophys Acta ; 1457(3): 118-28, 2000 Apr 21.
Article in English | MEDLINE | ID: mdl-10773157

ABSTRACT

Density separated trout erythrocytes, using a discontinuous Percoll gradient, yielded three distinct subfractions (top, middle and bottom) since older cells are characterized by increasing density. Cells from each subfraction were incubated with mitochondria-specific fluorescent probe Mitotracker and JC-1 in order to assess mitochondrial mass and membrane potential by means of cytofluorimetric analysis, confocal microscopy and subsequent computer-aided image analysis allowing a detailed investigation at single cell level. Both cytofluorimetric data and image analysis revealed changes in size and redistribution of mitochondria starting from the light fraction to the bottom. In particular in young erythrocytes small mitochondria were detected localized exclusively around the nucleus in a crown-like shape, the middle fraction revealed enlarged mitochondria partially scattered throughout the cytosol, whereas the last fraction represented again mitochondria with reduced size being distinctly dispersed throughout the cytosol in the cells. Concerning membrane potential considerations, our study revealed a dramatic decrease of DeltaPsi(m) in the bottom layer cell mitochondria compared to the top and unusual membrane potential increase of a subpopulation of enlarged mitochondria. DeltapH was also investigated in the three fractions by pretreating the cells with nigericin, allowing to confirm a mitochondrial energetic impairment in older cells.


Subject(s)
Erythrocytes/cytology , Mitochondria/physiology , Oncorhynchus mykiss/blood , Animals , Apoptosis , Benzimidazoles , Carbocyanines , Erythrocyte Aging , Erythrocytes/classification , Flow Cytometry , Fluorescent Dyes , Membrane Potentials , Microscopy, Confocal , Mitochondria/ultrastructure , Nigericin , Xanthenes
10.
Neuroscience ; 89(3): 991-7, 1999 Mar.
Article in English | MEDLINE | ID: mdl-10199630

ABSTRACT

Undifferentiated PC12 cells undergo apoptosis, via a calcium-induced calcium release mechanism, when the calcium-binding protein purified from bovine brain (native S100) is present in micromolar concentration in the medium. This process begins when S100 binds to specific membrane binding sites and involves up to 50% of the cell population. In the experiments reported here, we demonstrate that, by utilizing [3H]S100, the S100 protein can be displaced from its binding sites only during the first 10 min of incubation. This fact is due to an internalization mechanism, having a time-course with a plateau after 10-20 min of incubation. The native form of S100 is a mixture of two different S100 isoforms: S100A1 (20%) and S100B (80%). Using confocal microscopy and monoclonal antibodies, we demonstrated that only one of these isoforms, S100A1, was autoexpressed in more than 50% of the PC12 cells analysed. After cell incubation with 2 microM native S100, S100B also appears in PC12 cells, with a maximum presence after 10 min of incubation. This fact seems to indicate that this isoform, at least, is effectively translocated when stimulated with external native S100. From the data reported, it is possible to hypothesize that, in PC12 cells, a possible homeostatic mechanism is present that can counteract the effect of a continuously applied lethal stimulus (stimuli) on cell viability.


Subject(s)
Apoptosis/drug effects , Calcium Signaling/drug effects , PC12 Cells/drug effects , Protein Isoforms/pharmacology , S100 Proteins/pharmacology , Animals , Binding Sites , Calcium Signaling/physiology , Cattle , Endocytosis , Homeostasis , Microscopy, Confocal , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Protein Isoforms/biosynthesis , Protein Isoforms/genetics , Rats , S100 Proteins/biosynthesis , S100 Proteins/classification , S100 Proteins/genetics
11.
Clin Infect Dis ; 28(4): 866-72, 1999 Apr.
Article in English | MEDLINE | ID: mdl-10825052

ABSTRACT

Two large outbreaks of Q fever occurred in 1987 and 1988 in an agricultural community for the rehabilitation of drug users. Approximately 40% of the residents were human immunodeficiency virus (HIV)-positive. Two hundred thirty-five residents presented with clinical evidence of a flulike syndrome that was confirmed to be Q fever; moreover, a large proportion of residents developed an asymptomatic infection. Clinical signs and symptoms were rather nonspecific: fever, malaise, and muscle pain that were often associated with pulmonary symptoms. Single or multiple opacities were detected, with mild interstitial inflammation evident on chest roentgenograms. The source of infection was the sheepfold, which is part of the stock-farming activity of the community. Both outbreaks occurred just after lambing had begun. Residents who were exposed during the first epidemic were protected in the second one. The attack rate among HIV-positive residents was significantly higher than that among HIV-negative residents in the first outbreak, whereas only a slight, marginally significant difference was observed in the second outbreak. The clinical features of Q fever did not differ between HIV-positive and HIV-negative individuals. No cases of relapse or chronic disease were observed.


Subject(s)
Disease Outbreaks , HIV Infections/complications , Q Fever/epidemiology , Residential Facilities , Substance Abuse Treatment Centers , Substance Abuse, Intravenous/complications , Adult , Antibodies, Bacterial/blood , Coxiella burnetii/immunology , Female , Humans , Incidence , Italy/epidemiology , Male , Q Fever/microbiology , Risk Factors , Substance Abuse, Intravenous/rehabilitation
12.
Eur J Morphol ; 36 Suppl: 222-9, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9825927

ABSTRACT

Double lectin labeling for confocal microscopy and lectin-protein A-gold binding for electron microscopy were applied to the mouse sublingual gland in order to study surface and cytoplasmic sialoglycoconjugates. For this purpose, serially cut sections were submitted to sialidase followed by incubation with lectins recognizing usually acceptor sugars for terminal sialic acids. At the electron microscope level, the residues subtended to sialic acid were individually identified on adjacent sections by an indirect technique of labeling, whereas with confocal microscopy the above sugars were simultaneously visualized on the same section by a double staining method using fluorescein isothiocyanate (FITC)- and tetramethylrhodamine isothiocyanate (TRITC)-conjugated lectins. Acinar cells were found to contain the terminal sequence sialic acid-beta-galactose in abundance while the sequence sialic acid-alpha-N-acetylgalactosamine appeared to be present in modest amounts. Both sialoglycoconjugates were homogeneously codistributed inside acinar cells. The combination with a saponification method also allowed the occurrence of C4 acetylated sialic acids linked to beta-galactose to be discovered, at the electron microscope level, on acinar cell secretory products.


Subject(s)
Microscopy, Confocal/methods , Microscopy, Immunoelectron/methods , Sialoglycoproteins/analysis , Sublingual Gland/chemistry , Sublingual Gland/cytology , Animals , Epithelial Cells/chemistry , Epithelial Cells/enzymology , Epithelial Cells/ultrastructure , Female , Male , Mice , Microscopy, Electron/methods , Neuraminidase/analysis , Sublingual Gland/ultrastructure
13.
J Infect Dis ; 176(4): 969-75, 1997 Oct.
Article in English | MEDLINE | ID: mdl-9333155

ABSTRACT

The natural history of cryptosporidiosis was investigated during a waterborne outbreak among 1731 members of a drug rehabilitation community in Italy; 19.6% of the members were positive for human immunodeficiency virus (HIV). Demographic and clinical information and pre-outbreak serum samples were available. Clinical data were analyzed, stratifying the study population by HIV serostatus and CD4 cell count. The attack rate of clinical cryptosporidiosis was 13.6% among HIV-negative individuals and 30.7% among HIV-positive individuals, although in the latter, it varied according to CD4 cell count. Clinical symptoms and their duration were also related to CD4 cell count. Chronic symptoms were observed in only 16 individuals (15.4%), who all had <150 CD4 cells at the onset of the illness. Among a systematic sample of 198 individuals, 14.1% already had anti-Cryptosporidium antibodies before the outbreak, and 51.2% developed specific antibodies during the outbreak. The development and clinical manifestations of cryptosporidiosis were strongly influenced by the level of HIV-induced immunosuppression.


Subject(s)
Cryptosporidiosis/epidemiology , HIV Infections/complications , Adolescent , Adult , Aged , Animals , Antibodies, Protozoan/analysis , CD4 Lymphocyte Count , Child , Child, Preschool , Chronic Disease , Cryptosporidiosis/diagnosis , Cryptosporidiosis/immunology , Cryptosporidium parvum/immunology , Disease Outbreaks , Female , HIV Infections/immunology , HIV Seronegativity , HIV Seropositivity , Humans , Immunocompromised Host , Immunoglobulin G/analysis , Infant , Infant, Newborn , Italy/epidemiology , Longitudinal Studies , Male , Middle Aged , Risk Factors , Seroepidemiologic Studies , Substance Abuse, Intravenous/immunology , Substance Abuse, Intravenous/virology , Water Supply/analysis
14.
Cell Motil Cytoskeleton ; 38(4): 329-40, 1997.
Article in English | MEDLINE | ID: mdl-9415375

ABSTRACT

In cold poikilotherm organisms, microtubule assembly is promoted at temperatures below 4 degrees C and cold-induced depolymerization is prevented. On the basis of the results of investigations on cold-adapted fishes, the property of cold adaptation is ascribed to intrinsic characteristics of the tubulins. To fully understand cold adaptation, we studied the tubulins of Euplotes focardii, an Antarctic ciliated protozoan adapted to temperatures ranging from -2 to +4 degrees C. In this organism, we had previously sequenced one beta-tubulin gene and, then identified three other genes (denoted as beta-T1, beta-T2, beta-T3 and beta-T4). Here we report that the amino acid sequence of the carboxy-terminal domain predicted from the beta-T3 gene (apparently the most expressed of the gene family) contains six modifications (five substitutions and one insertion) of conserved residues, unique with respect to all the other known beta-tubulin sequences. These modifications can change the structural conformation of the carboxy-terminal domain. Furthermore, in the variable terminal end of that domain, a consensus sequence for a phosphorylation site is present, and the residue Glu-438, the most frequent site for polyglutamylation in beta-tubulin, is substituted by Asp. Starting from these observations, we showed that in E. focardii only alpha-tubulin is polyglutamylated, while beta-tubulin undergoes phosphorylation. Polyglutamylated microtubules appear to colocalize with cilia and microtubular bundles, all structures in which microtubules undergo a sliding process. This finding supports the idea that alpha-tubulin polyglutamylation is involved in the interaction between tubulin and motor microtubule-associated proteins. Phosphorylation, usually a rare posttranslational modification of beta-tubulin, which is found extensively distributed in the beta-tubulin of this cold-adapted organism, may play a determinant role in the dynamic of polymerization and depolymerization at low temperatures.


Subject(s)
Acclimatization , Cold Temperature , Euplotes/metabolism , Microtubules/metabolism , Protein Processing, Post-Translational , Tubulin/metabolism , Amino Acid Sequence , Animals , Antarctic Regions , Euplotes/genetics , Genes, Protozoan , Glutamates , Microtubules/physiology , Molecular Sequence Data , Phosphorylation , Sequence Analysis, DNA
15.
Clin Infect Dis ; 23(1): 107-13, 1996 Jul.
Article in English | MEDLINE | ID: mdl-8816138

ABSTRACT

Although the association among bacterial pneumonia, human immunodeficiency virus (HIV) infection, and injection-drug use seems to have been well established, accurate estimates of the risk of community-acquired pneumonia among HIV-positive and HIV-negative injection-drug users (IDUs) are still needed. To estimate the incidence of pneumonia in a community of former IDUs, we followed 4,236 persons between 1991 and 1994; 1,114 (26.3%) were HIV-positive and 3,122 (73.7%) were HIV-negative. All patients were evaluated for pneumonia by standard criteria, a serum sample was obtained from each participant at least once a year, and laboratory values were monitored. Overall, 149 episodes of pneumonia occurred among HIV-positive patients and 61 among HIV-negative patients; incidence rates were 90.5 and 14.2 (per 1,000 person-years), respectively. The most common etiologic agents were Streptococcus pneumoniae, Chlamydia pneumoniae, and Haemophilus influenzae. Among the HIV-positive former IDUs, there was a 1.37-fold increase in the relative risk of pneumonia for every decrease of 100/mm3 in the CD4 cell count (95% confidence interval, 1.16-1.61). The incidence of community-acquired pneumonia was markedly higher among HIV-positive participants than among HIV-negative ones, a finding similar to that concerning the general population.


Subject(s)
AIDS-Related Opportunistic Infections/epidemiology , Pneumonia, Bacterial/epidemiology , AIDS-Related Opportunistic Infections/complications , AIDS-Related Opportunistic Infections/etiology , Adult , CD4 Lymphocyte Count , Chlamydia Infections/complications , Chlamydia Infections/epidemiology , Chlamydia Infections/etiology , Chlamydophila pneumoniae , Cohort Studies , Community-Acquired Infections/complications , Community-Acquired Infections/epidemiology , Community-Acquired Infections/etiology , Female , Haemophilus Infections/complications , Haemophilus Infections/epidemiology , Haemophilus Infections/etiology , Haemophilus influenzae , Humans , Italy/epidemiology , Male , Pneumonia, Bacterial/complications , Pneumonia, Bacterial/etiology , Pneumonia, Pneumococcal/complications , Pneumonia, Pneumococcal/epidemiology , Pneumonia, Pneumococcal/etiology , Recurrence , Risk Factors , Substance Abuse, Intravenous/complications
16.
J Eukaryot Microbiol ; 41(4): 420-7, 1994.
Article in English | MEDLINE | ID: mdl-8087111

ABSTRACT

Four different tubulin genes were identified in the somatic nucleus (macronucleus) of Euplotes focardii, a strictly cold-adapted, Antarctic ciliate: one of 1,800 bp for alpha-tubulin and three of 2,150, 1,900, and 1,600 bp, respectively, for beta-tubulin. Preliminarily analysed for restriction fragment length polymorphisms, these genes showed remarkable differences in organisation from tubulin genes of other ciliates which live in temperate areas and were analysed in parallel with E. focardii. The complete coding sequence of the 1,600 bp beta-tubulin gene was then determined and shown to contain unique structural features of potential importance for E. focardii microtubule organization and activity. Of eight unique substitutions detected, seven were concentrated in the large amino terminal domain of the molecule that directly interacts with the carboxy terminal region of alpha-tubulin for heterodimer formation. Sequence analysis of the cloned gene revealed, in addition, a potential new exception in the use of the genetic code by ciliates. A TAG codon was aligned in correspondence with Trp-21 which is strictly conserved in every tubulin sequence so far determined.


Subject(s)
DNA, Protozoan/genetics , Euplotes/genetics , Genes, Protozoan , Tubulin/genetics , Amino Acid Sequence , Animals , Base Sequence , Blotting, Southern , Cloning, Molecular , DNA, Protozoan/analysis , DNA, Protozoan/biosynthesis , Euplotes/isolation & purification , Genome , Molecular Sequence Data , Polymerase Chain Reaction , Restriction Mapping , Tubulin/analysis
17.
Hum Genet ; 87(5): 579-82, 1991 Sep.
Article in English | MEDLINE | ID: mdl-1916760

ABSTRACT

By analyzing c-myc specific fragments from white blood cell DNAs of 98 gastric cancer patients and 46 control subjects, we observed 6 unexpected patterns due to presence of a variant c-myc gene in addition to the normal gene. Restriction enzyme mapping indicated that the variant c-myc gene was the result of a 5' deletion including the first exon and part of the first intron. The deleted region, non-coding for the functional c-myc protein, contains sequences involved in the regulation of transcription. We therefore analyzed the c-myc mRNAs from a subject carrying the truncated gene and from a subject homozygous for the normal gene in Northern blotting experiments: the mRNAs were indistinguishable, both qualitatively and quantitatively. Family analysis demonstrated that the truncated gene is inherited in a Mendelian fashion. Population studies showed that the allele, both in patients and in control subjects, reaches a polymorphic frequency (2.1% for the whole sample) and that it is not associated with a risk of cancer.


Subject(s)
Genes, myc , Mutation , Stomach Neoplasms/genetics , Blotting, Northern , Blotting, Southern , Cells, Cultured , Deoxyribonuclease EcoRI , Gene Expression , Humans , Italy/epidemiology , Restriction Mapping , Risk Factors , Stomach Neoplasms/epidemiology
18.
Gene Geogr ; 4(3): 135-7, 1990 Dec.
Article in English | MEDLINE | ID: mdl-2129614

ABSTRACT

A sample of about 300 subjects from the Italian population of the Oltrepò Pavese, in Lombardy, was studied for 6 polymorphic genetic markers: ACP1, ADA, ESD, GLO1, PGM1 subtyping and HP. The observed gene frequencies were: ACP1*A = .267, ACP1*B = .697, ACP1*C = .036; ADA*2 = .060; ESD*2 = .119; GLO1*1 = .375; PGM1*1S = .688, PGM1*1F = .095, PGM1*2S = .175, PGM1*2F = .042; HP*1 = .362.


Subject(s)
Blood Proteins/genetics , Erythrocytes/enzymology , Polymorphism, Genetic , Gene Frequency , Humans , Italy
19.
Chir Organi Mov ; 75(4): 347-51, 1990.
Article in English, Italian | MEDLINE | ID: mdl-2098222

ABSTRACT

Most of the halo connection devices currently used with both the halo-plaster and halo-vest cannot be adjusted on the different displacement planes during reduction treatment. This makes it difficult to obtain good radiograms for the interposition of connection bars. The connection device designed by the Rizzoli Orthopaedic Institute (D.R. IOR) allows for movements in rotation and translation, preventing loosening of the system. Moreover, radiographic monitoring may be obtained in the best conditions possible, by moving the connection rods backwards or forwards without changing the spinal axis.


Subject(s)
Cervical Vertebrae/injuries , Orthopedic Fixation Devices , Traction/instrumentation , Equipment Design , Humans , Joint Dislocations/etiology , Joint Dislocations/therapy
20.
J Radiol ; 71(1): 33-43, 1990 Jan.
Article in French | MEDLINE | ID: mdl-2179538

ABSTRACT

The authors report a retrospective study of 55 cases, 34 hematomas and 21 cytosteatonecrosis (CSN) of the breast, during 15 years. The mammary hematoma can appear with an encapsuled or diffused form, or in 40% of cases without radiographic model. The diagnosis of CSN, is easy, such as ringed, macrocalcified, or oil cystic, but when it is the case of solid cicatriciel mass, it is difficult to distinguish it from mammary carcinoma, in approximatively half of the cases. The etiopathogenic discussion, display, traumatic features, ischemic cellular disease, such as mammary infarct, inflammatory lesions, duct ectasia, anticoagulant drugs, needle aspiration... Even though nodular lesion may be a carcinoma, a very suggestive lesion with spicules and skin retraction may be benign. The follow up, or histological examination by biopsie or surgery, is always essential.


Subject(s)
Breast Diseases/diagnosis , Fat Necrosis/diagnosis , Hematoma/diagnosis , Necrosis/diagnosis , Adult , Aged , Breast Diseases/diagnostic imaging , Breast Diseases/pathology , Diagnosis, Differential , Fat Necrosis/diagnostic imaging , Fat Necrosis/pathology , Female , Follow-Up Studies , Hematoma/diagnostic imaging , Hematoma/pathology , Humans , Middle Aged , Radiography , Retrospective Studies , Time Factors , Ultrasonography
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