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1.
Transpl Infect Dis ; 13(4): 359-65, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21355970

ABSTRACT

The characteristics of Escherichia coli strains causing bacteremia in profoundly immunosuppressed patients such as transplant recipients are undefined. The phylogenetic group and the virulence genotype of 57 distinct E. coli strains that caused bacteremia in 53 liver transplant recipients were investigated, and the association of these characteristics with host factors and in-hospital mortality was examined. Phylogenetic groups A, B1, B2, and D accounted for 39%, 10%, 25%, and 26% of the isolates, respectively. The most prevalent virulence genes were fyuA (yersiniabactin system: 70%) and iutA (aerobactin system: 63%), whereas hlyA (alpha-hemolysin) and cnf1 (cytotoxic necrotizing factor 1) occurred in only 14% and 12% of isolates, respectively. Most virulence genes were significantly more prevalent among group B2 and D isolates, vs. group A and B1 isolates. The overall rate of in-hospital mortality after E. coli bacteremia was 20%. Predictors of mortality included onset of bacteremia within 30 days of transplantation or during the intensive care unit stay, and non-urinary source and cutaneous source, but not E. coli phylogenetic group or virulence profile. Compared with historical E. coli bloodstream isolates from non-transplant patients, those from liver transplant recipients are characterized by a higher prevalence of groups A and B1 isolates and reduced virulence gene content. This finding can be explained by the severely immunocompromised status of the patients and the predominance of abdominal-source bacteremic episodes. Time of onset and source of bacteremia, not bacterial characteristics, predict mortality.


Subject(s)
Bacteremia/epidemiology , Escherichia coli/genetics , Liver Transplantation/adverse effects , Molecular Epidemiology , Phylogeny , Virulence Factors/genetics , Adult , Aged , Bacteremia/microbiology , Bacteremia/mortality , Escherichia coli/pathogenicity , Escherichia coli Infections/epidemiology , Escherichia coli Infections/microbiology , Escherichia coli Infections/mortality , Escherichia coli Proteins/genetics , Female , Genotype , Hospital Mortality , Humans , Male , Middle Aged , Virulence/genetics
2.
Science ; 253(5017): 292-8, 1991 Jul 19.
Article in English | MEDLINE | ID: mdl-1650033

ABSTRACT

Incubation of the apoB2 subunit of Escherichia coli ribonucleotide reductase with Fe2+ and O2 produces native B2, which contains the tyrosyl radical-dinuclear iron cluster cofactor required for nucleotide reduction. The chemical mechanism of this reconstitution reaction was investigated by stopped-flow absorption spectroscopy and by rapid freeze-quench EPR (electron paramagnetic resonance) spectroscopy. Two novel intermediates have been detected in the reaction. The first exhibits a broad absorption band centered at 565 nanometers. Based on known model chemistry, this intermediate is proposed to be a mu-peroxodiferric complex. The second intermediate exhibits a broad absorption band centered at 360 nanometers and a sharp, isotropic EPR signal with g = 2.00. When the reaction is carried out with 57Fe2+, this EPR signal is broadened, demonstrating that the intermediate is an iron-coupled radical. Variation of the ratio of Fe2+ to B2 in the reaction and comparison of the rates of formation and decay of the intermediates to the rate of formation of the tyrosyl radical (.Y122) suggest that both intermediates can generate .Y122. This conclusion is supported by the fact that both intermediates exhibit an increased lifetime in a mutant B2 subunit (B2-Y122F) lacking the oxidizable Y122. Based on these kinetic and spectroscopic data, a mechanism for the reaction is proposed. Unlike reactions catalyzed by heme-iron peroxidases, oxygenases, and model complexes, the reconstitution reaction appears not to involve high-valent iron intermediates.


Subject(s)
Iron/metabolism , Oxygen/metabolism , Ribonucleotide Reductases/metabolism , Tyrosine/metabolism , Binding Sites , Electron Spin Resonance Spectroscopy , Escherichia coli/enzymology , Kinetics , Macromolecular Substances , Models, Theoretical , Spectrophotometry, Ultraviolet , Time Factors
3.
Science ; 287(5450): 122-5, 2000 Jan 07.
Article in English | MEDLINE | ID: mdl-10615044

ABSTRACT

The reaction of oxygen with protein diiron sites is important in bioorganic syntheses and biomineralization. An unusually short Fe-Fe distance of 2.53 angstroms was found in the diiron (mu-1,2 peroxodiferric) intermediate that forms in the early steps of ferritin biomineralization. This distance suggests the presence of a unique triply bridged structure. The Fe-Fe distances in the mu-1, 2 peroxodiferric complexes that were characterized previously are much longer (3.1 to 4.0 angstroms). The 2.53 angstrom Fe-Fe distance requires a small Fe-O-O angle (approximately 106 degrees to 107 degrees). This geometry should favor decay of the peroxodiferric complex by the release of H2O2 and mu-oxo or mu-hydroxo diferric biomineral precursors rather than by oxidation of the organic substrate. Geometrical differences may thus explain how diiron sites can function either as a substrate (in ferritin biomineralization) or as a cofactor (in O2 activation).


Subject(s)
Ferric Compounds/metabolism , Ferritins/metabolism , Ferrous Compounds/metabolism , Oxygen/metabolism , Chemical Phenomena , Chemistry, Physical , Ferric Compounds/chemistry , Ferritins/chemistry , Ferrous Compounds/chemistry , Fourier Analysis , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Spectroscopy, Mossbauer , Spectrum Analysis , Thermodynamics , X-Rays
4.
Integr Biol (Camb) ; 10(8): 450-463, 2018 08 01.
Article in English | MEDLINE | ID: mdl-30027970

ABSTRACT

Sensory neurons embedded in skin are responsible for the sense of touch. In humans and other mammals, touch sensation depends on thousands of diverse somatosensory neurons. By contrast, Caenorhabditis elegans nematodes have six gentle touch receptor neurons linked to simple behaviors. The classical touch assay uses an eyebrow hair to stimulate freely moving C. elegans, evoking evasive behavioral responses. This assay has led to the discovery of genes required for touch sensation, but does not provide control over stimulus strength or position. Here, we present an integrated system for performing automated, quantitative touch assays that circumvents these limitations and incorporates automated measurements of behavioral responses. The Highly Automated Worm Kicker (HAWK) unites a microfabricated silicon force sensor holding a glass bead forming the contact surface and video analysis with real-time force and position control. Using this system, we stimulated animals along the anterior-posterior axis and compared responses in wild-type and spc-1(dn) transgenic animals, which have a touch defect due to expression of a dominant-negative α-spectrin protein fragment. As expected from prior studies, delivering large stimuli anterior and posterior to the mid-point of the body evoked a reversal and a speed-up, respectively. The probability of evoking a response of either kind depended on stimulus strength and location; once initiated, the magnitude and quality of both reversal and speed-up behavioral responses were uncorrelated with stimulus location, strength, or the absence or presence of the spc-1(dn) transgene. Wild-type animals failed to respond when the stimulus was applied near the mid-point. These results show that stimulus strength and location govern the activation of a characteristic motor program and that the C. elegans body surface consists of two receptive fields separated by a gap.


Subject(s)
Caenorhabditis elegans/physiology , Animals , Animals, Genetically Modified , Behavior, Animal/physiology , Caenorhabditis elegans/cytology , Caenorhabditis elegans/genetics , Caenorhabditis elegans Proteins/genetics , Caenorhabditis elegans Proteins/physiology , Computer Systems , Mechanoreceptors/physiology , Mechanotransduction, Cellular/physiology , Physical Stimulation/instrumentation , Sensory Receptor Cells/physiology , Spectrin/deficiency , Spectrin/genetics , Spectrin/physiology , Touch/physiology
5.
FEMS Microbiol Rev ; 4(4): 299-344, 1988 Dec.
Article in English | MEDLINE | ID: mdl-3078655

ABSTRACT

Three types of hydrogenases have been isolated from the sulfate-reducing bacteria of the genus Desulfovibrio. They differ in their subunit and metal compositions, physico-chemical characteristics, amino acid sequences, immunological reactivities, gene structures and their catalytic properties. Broadly, the hydrogenases can be considered as 'iron only' hydrogenases and nickel-containing hydrogenases. The iron-sulfur-containing hydrogenase ([Fe] hydrogenase) contains two ferredoxin-type (4Fe-4S) clusters and an atypical iron-sulfur center believed to be involved in the activation of H2. The [Fe] hydrogenase has the highest specific activity in the evolution and consumption of hydrogen and in the proton-deuterium exchange reaction and this enzyme is the most sensitive to CO and NO2-. It is not present in all species of Desulfovibrio. The nickel-(iron-sulfur)-containing hydrogenases [( NiFe] hydrogenases) possess two (4Fe-4S) centers and one (3Fe-xS) cluster in addition to nickel and have been found in all species of Desulfovibrio so far investigated. The redox active nickel is ligated by at least two cysteinyl thiolate residues and the [NiFe] hydrogenases are particularly resistant to inhibitors such as CO and NO2-. The genes encoding the large and small subunits of a periplasmic and a membrane-bound species of the [NiFe] hydrogenase have been cloned in Escherichia (E.) coli and sequenced. Their derived amino acid sequences exhibit a high degree of homology (70%); however, they show no obvious metal-binding sites or homology with the derived amino acid sequence of the [Fe] hydrogenase. The third class is represented by the nickel-(iron-sulfur)-selenium-containing hydrogenases [( NiFe-Se] hydrogenases) which contain nickel and selenium in equimolecular amounts plus (4Fe-4S) centers and are only found in some species of Desulfovibrio. The genes encoding the large and small subunits of the periplasmic hydrogenase from Desulfovibrio (D.) baculatus (DSM 1743) have been cloned in E. coli and sequenced. The derived amino acid sequence exhibits homology (40%) with the sequence of the [NiFe] hydrogenase and the carboxy-terminus of the gene for the large subunit contains a codon (TGA) for selenocysteine in a position homologous to a codon (TGC) for cysteine in the large subunit of the [NiFe] hydrogenase. EXAFS and EPR studies with the 77Se-enriched D. baculatus hydrogenase indicate that selenium is a ligand to nickel and suggest that the redox active nickel is ligated by at least two cysteinyl thiolate and one selenocysteine selenolate residues.(ABSTRACT TRUNCATED AT 400 WORDS)


Subject(s)
Desulfovibrio/enzymology , Hydrogenase/analysis , Amino Acid Sequence , Desulfovibrio/genetics , Hydrogenase/genetics , Hydrogenase/physiology , Molecular Sequence Data
6.
Biochim Biophys Acta ; 534(2): 295-306, 1978 Jun 21.
Article in English | MEDLINE | ID: mdl-208633

ABSTRACT

We have studied cytochrome c2 from Rhodospirllum rubrum with Mössbauer spectroscopy and electron paramagnetic resonance. The Mössbauer data on the ferric protein, taken in external magnetic fields up to 50 kG, were analyzed within the framework of the ligand field model commonly used to evaluate low-spin ferric heme compounds. The data analysis shows that the determinant of the electronic g-tensor, i.e. the product gxgygz, is positive for cytochrome c2. We have reanalyzed published Mössbauer data of some low-spin ferric heme proteins with respect to the sign of the g-tensor determinant. We find that gxgygz is also positive for the cytochromes c, bs, and P-450, and for chloroperoxidase.


Subject(s)
Cytochrome c Group , Rhodospirillum rubrum/enzymology , Electron Spin Resonance Spectroscopy , Hemeproteins , Iron , Mathematics , Protein Conformation , Spectrum Analysis
7.
Biochim Biophys Acta ; 576(1): 192-203, 1979 Jan 25.
Article in English | MEDLINE | ID: mdl-760805

ABSTRACT

We have studied the MoFe protein from Azotobacter vinelandii OP with Mössbauer spectroscopy in applied magnetic fields up to 50 kG. The results are as follows. (1) The Mössbauer spectra of the S = 3/2 centers, which reside on the cofactor of nitrogenase, have been decomposed into six subcomponents. This suggests that each center contains 5-7, most probably 6, Fe atoms, thus confirming our earlier conclusions which were based on the quantitation of EPR data and on the assumption that the MoFe protein contains (30 +/- 2) Fe atoms. (2) Analysis of the high-field data shows that three subsites are characterized by a positive magnetic hyperfine coupling constant, A0, while A0 is negative for the other three sites. This observation demonstrates that the S = 3/2 centers are spin-coupled structures. (3) The zero-field splitting parameter D = +(6 +/- 1.5) cm-1 obtained from the Mössbauer data is in good agreement with our earlier EPR results, D approximately +5.5 cm-1. (4) The resolution of the Mössbauer spectra of the MoFe protein can be dramatically increased by employing Fourier transform deconvolution techniques. This allows a clear demonstration of spectral component S.


Subject(s)
Azotobacter/enzymology , Nitrogenase , Iron/analysis , Molybdenum/analysis , Protein Binding , Protein Conformation , Spectrum Analysis
8.
Biochim Biophys Acta ; 623(1): 124-38, 1980 May 29.
Article in English | MEDLINE | ID: mdl-6246963

ABSTRACT

We have studied the molybdenum-protein (MoFe protein) from Clostridium pasteurianum with Mössbauer spectroscopy in the temperature range from 1.5 to 200 K in magnetic fields up to 55 kG. Except for some small differences in the hyperfine parameters the results for the C. pasteurianum protein are essentially the same as those published previously for the protein from Azotobacter vinelandii, i.e. (30 +/- 2) Fe atoms partition into two identical cofactor centers M (each center most likely containing six Fe atoms and one Mo atom), four P-clusters (each center containing four Fe atoms), and one iron environment labeled S (about two Fe atoms per holoenzyme). We have analyzed the spectra of the cofactor centers in three distinct oxidation states, Formula: (see test). The diamagnetic (electronic spin S = 0) state MOX is attained by oxidation of the native, EPR-active (S = 3/2) state MN. The reduced state MR is observed in steady state under nitrogen fixing conditions; high-field Mössbauer studies show that the cofactor centers are paramagnetic (integer electronic spin S greater than or equal to 1) in the state MR. We have evaluated the complex high-field spectra resulting from the P-clusters in the oxidized state POX. The analysis shows that one iron site is characterized by a positive hyperfine coupling constant A0 while the other three sites have A0 less than 0. A slightly modified set of parameters also fits the high-field data of the MoFe protein from A. vinelandii. Finally, we will present a discussion summarizing our principle results obtained to date for the proteins from A. vinelandii and C. pasteurianum.


Subject(s)
Clostridium/enzymology , Iron/analysis , Molybdenum/analysis , Molybdoferredoxin/analysis , Nitrogenase , Electron Spin Resonance Spectroscopy , Mathematics , Phenothiazines
9.
Biochim Biophys Acta ; 1144(3): 302-8, 1993 Oct 04.
Article in English | MEDLINE | ID: mdl-8399280

ABSTRACT

Redox intermediates of D. desulfuricans ATCC 27774 [NiFe] hydrogenase were generated under dihydrogen. Detailed redox titrations, coupled to EPR measurements, give access to the mid-point redox potentials of the iron-sulfur centers and of the Nickel-B signal that represents the ready form of the enzyme. The interaction between the dihydrogen molecule and the nickel centre was probed by the observation of an isotopic effect on the EPR signals detected in turnover conditions, by comparison of the H2O/H2 and D2O/D2-reacted samples.


Subject(s)
Desulfovibrio/enzymology , Hydrogenase/chemistry , Binding Sites , Desulfovibrio/genetics , Electromagnetic Fields , Electron Spin Resonance Spectroscopy , Oxidation-Reduction , Temperature
10.
Hum Gene Ther ; 9(9): 1293-301, 1998 Jun 10.
Article in English | MEDLINE | ID: mdl-9650614

ABSTRACT

Retrovirus-mediated gene delivery into hepatocytes in vivo provides long-term gene expression, which is of great importance for treating most genetic and metabolic disorders. However, clinical application has not been realized because of the requirement for prior 70% partial hepatectomy or chemical (toxic) liver injury to initiate hepatocyte replication at the time of retroviral gene transduction. In this paper, we describe a novel gene delivery system that uses recombinant hepatocyte growth factor (rHGF) prior to retrovirus-mediated in vivo gene transfer in the liver without partial hepatectomy or liver injury. A single retroviral infusion through the portal vein following five systemic injections (via the tail vein) of 100 microg/kg rHGF resulted in a 10.4% 5-bromo-2'-deoxyuridine (BrdU) labeling index (BLI) and 0.14% retroviral gene transduction efficiency (RGTE) in hepatocytes, which were 6.3- and 12.9-fold higher than those of controls, respectively. Modest additional increases in BLI and RGTE (13.4% and 0.22%, respectively) were seen after five systemic injections of 500 microg/kg rHGF. The correlation between BLI and RGTE was statistically confirmed regardless of treatment. When rats received multiple retroviral infusions through a cannulated portal vein following five portal injections of 100 microg/kg rHGF, RGTE was dramatically increased (1.3%) and in some areas of the liver exceeded more than 10%. There was no evidence of liver injury in any animal. This approach has great potential for clinical application in terms of avoiding invasive procedures or liver injury.


Subject(s)
Gene Transfer Techniques , Genetic Therapy/methods , Hepatocyte Growth Factor/administration & dosage , Hepatocyte Growth Factor/genetics , Liver/cytology , Retroviridae/genetics , Animals , Cell Division , Genetic Vectors , Immunohistochemistry , Male , Rats , Rats, Inbred Lew , Recombinant Proteins/administration & dosage , Transduction, Genetic
11.
FEBS Lett ; 228(1): 85-8, 1988 Feb 08.
Article in English | MEDLINE | ID: mdl-2830138

ABSTRACT

The effect of exposure to carbon monoxide on the activity of the (Fe) hydrogenase from Desulfovibrio vulgaris has been determined. Concentrations of carbon monoxide which completely inhibit hydrogenase activity and induce formation of the axial g = 2.06 EPR signal up to 0.8 spin/molecule do not cause irreversible inhibition of the (Fe) hydrogenase.


Subject(s)
Carbon Monoxide/pharmacology , Desulfovibrio/enzymology , Hydrogenase/antagonists & inhibitors , Electron Spin Resonance Spectroscopy , Enzyme Reactivators , Temperature
12.
Methods Enzymol ; 258: 278-303, 1995.
Article in English | MEDLINE | ID: mdl-8524156

ABSTRACT

The SF-Abs, RFQ-EPR, and RFQ-Möss data on the R2 reconstitution reaction are all consistent with the mechanism of Scheme I, in which the intermediate X is the immediate precursor to the product cofactor, and illustrate how the continuous SF approach and the discontinuous RFQ methods can be complementary. Given the inherent differences in the methods, it should not be taken for granted that data from the two will be consistent. A number of problems can be associated with the RFQ approach. For example, isopentane could conceivably interfere with or alter the chemistry to be studied. A second potential problem involves temperature-dependent equilibria among different intermediate species. This problem has been encountered by Dooley et al. with the 6-hydroxydopa-requiring protein, plasma amine oxidase and was previously observed with the adenosylcobalamin-dependent ribonucleotide reductase by Blakley and co-workers. This potential complication should be considered when discrepancies arise between SF and RFQ data and in low temperature structural studies of reactive intermediates in general. Each of the three methods employed can yield time-resolved quantitation of reaction components. In this regard, SF-Abs has the disadvantage of poor resolution, such that quantitation of individual components most often requires sophisticated mathematical analysis. Obvious advantages to the RFQ-Möss method are the presence of an internal standard (the known amount of 57Fe being proportional to the total absorption area) and the spectroscopic activity of all reaction components which contain iron. In our hands, quantitation by RFQ-EPR was most problematic and least reproducible. This irreproducibility most likely relates to heterogeneity among samples in terms of volume and density. As discussed in detail by Ballou and Palmer, the packing factor, which relates to the fraction of a sample made up by the reaction solution (the remainder being frozen isopentane), is dependent on the investigator. Given this caveat, it is not surprising that the RFQ-EPR data had the greatest uncertainty in our hands. Placing a chemically unreactive, EPR active standard in each reaction mixture could help alleviate this problem. Time-resolved Möss methods can be extremely powerful if excellent, nonoverlapping reference spectra of starting materials, products, and intermediates are available. All of the iron centers can be examined simultaneously. The problems associated with Möss arise from its extreme insensitivity. It takes millimolar solutions of proteins and several days for data collection of each time point.(ABSTRACT TRUNCATED AT 400 WORDS)


Subject(s)
Escherichia coli/enzymology , Ferric Compounds/chemistry , Ferric Compounds/metabolism , Ribonucleotide Reductases/chemistry , Ribonucleotide Reductases/metabolism , Coenzymes/chemistry , Coenzymes/metabolism , Electron Spin Resonance Spectroscopy/instrumentation , Electron Spin Resonance Spectroscopy/methods , Freezing , Iron/metabolism , Kinetics , Least-Squares Analysis , Oxidation-Reduction , Oxygen/metabolism , Sensitivity and Specificity , Spectrophotometry/methods , Spectroscopy, Mossbauer/methods , Time Factors
13.
J Am Diet Assoc ; 96(3): 243-6, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8613657

ABSTRACT

OBJECTIVE: To test the hypothesis that complete elimination of lactose is not necessary to ensure tolerance by lactose maldigesters. DESIGN: Double-blind, randomized protocol in which challenge doses of 0, 2, 6, 12, and 20 g lactose in water were fed to subjects after a 12-hour fast. SUBJECTS: 13 healthy, free-living adults who were lactose maldigesters. MAIN OUTCOME MEASURES: Breath hydrogen production (a measure of maldigestion) and symptom response to each challenge dose. STATISTICAL ANALYSIS: Analysis of variance was done to determine overall differences in mean hydrogen gas production (peak and sum of hours 1 through 8). Friedman's test was used to determine overall differences in the mean ranks for each symptom. Fisher's least significant difference test was used for multiple comparisons for hydrogen and symptom and data. RESULTS: Hydrogen production after consumption of the 0- and 2-g lactose doses was not significantly different. Hydrogen production increased with the 6-g dose. Intensity of abdominal pain increased when the dose of lactose was 12 g. Episodes of flatulence did not increase until the dose reached 20 g. No significant differences in the occurrence of diarrhea were observed after the five treatments. CONCLUSIONS: No significant increase in breath hydrogen production or intolerance symptoms occurred after consumption of a 2-g dose of lactose. Up to 6 g was tolerated, even though maldigestion could be measured at the 6-g dose. Thus, lactose maldigesters may be able to tolerate foods containing 6 g lactose or less per serving, such as hard cheeses and small servings (120 mL or less) of milk.


Subject(s)
Lactose Intolerance/physiopathology , Lactose/administration & dosage , Abdominal Pain , Adult , Breath Tests , Dose-Response Relationship, Drug , Double-Blind Method , Female , Flatulence , Humans , Hydrogen/analysis , Male
14.
Plast Reconstr Surg ; 105(1): 376-83; discussion 384-8, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10627007

ABSTRACT

An active depressor septi muscle can accentuate a drooping nasal tip and shorten the upper lip on animation. We have found that dissection and transposition of the depressor septi muscle during rhinoplasty can improve the tip-upper lip relationship in appropriately selected patients. Although the anatomy of the depressor septi muscle has been described, the anatomic variations of this muscle have not been previously reported. The goals of this study were two-fold: (1) to define the anatomic variations of the depressor septi muscle using 55 fresh cadaver dissections and (2) to develop a clinically applicable algorithm for modification of this muscle during rhinoplasty in those patients with a short upper lip and/or tip-upper lip imbalance. Fifty-five fresh cadavers were dissected, and the anatomic variations of the depressor septi muscle were recorded. Three variations of the depressor septi muscle were delineated: type I inserted fully into the orbicularis oris (62 percent); type II inserted into the periosteum and incompletely into the orbicularis oris (22 percent); and type III showed no, or rudimentary, depressor septi muscle (16 percent). Sixty-two patients over a 4-year period (from 1995 to 1999) were identified preoperatively with a hyperactive depressor septi diagnosed by a descending nasal tip and shortened upper lip on animation. These patients underwent dissection and transposition (not resection) of the paired depressor septi during rhinoplasty with improvement or correction of the tip-upper lip imbalance in 88 percent of cases. The anatomic study, surgical indications, rationale for the operative technique, and clinical cases are presented. Dissection and transposition of the depressor septi is a valuable adjunct to rhinoplasty in patients with a type I or II muscle variant.


Subject(s)
Facial Muscles/surgery , Rhinoplasty/methods , Adult , Algorithms , Facial Muscles/pathology , Female , Humans , Male , Nose/pathology , Reference Values , Smiling/physiology
15.
Acta Cytol ; 45(4): 519-24, 2001.
Article in English | MEDLINE | ID: mdl-11480712

ABSTRACT

OBJECTIVE: To compare the accuracy of thin-layer cytology with Autocyte PREP (TriPath Imaging Inc., Burlington, North Carolina, U.S.A.) with conventional smears in 500 women undergoing cervical cone biopsy. STUDY DESIGN: The study was performed among 500 consecutive women presenting for cone biopsy for high grade cervical intraepithelial neoplasia (CIN) on biopsy in 350 (70%) and discrepant cytology/colpohistology in 150 (30%). Before performing a cone biopsy, two cervical samples were collected for conventional smears and thin-layer cytologic slides, with randomization of the order. Conventional smears were stained and diagnosed at Pasteur Cerba, while thin-layer cytologic slides were processed at a local TriPath office (Meylan, France) and sent in a masked fashion for screening at Pasteur Cerba. Any slides initially read as normal were reviewed again and reported without knowledge of the other cytologic or cone biopsy data. The final cytologic diagnoses for the two methods were compared with histopathology of the cone biopsy. RESULTS: The conventional smear was unsatisfactory in 58 (11.6%) of cases, while there were 4 (0.8%) unsatisfactory thin-layer cytologic slides (P < .001). Endocervical cells were missing from 31 (6.2%) of conventional smears and 34 (6.8%) of thin-layer cytologic slides. For the pooled data, sensitivities of conventional smear and thin layer for detecting high grade CIN (0.82% and 0.86%, respectively) were similar as were specificities (0.40% and 0.43%, respectively). When first samples were compared, the sensitivities of the conventional smear and thin layer for high grade CIN were 0.79% and 0.89%, respectively (P = .02), with corresponding specificities of 0.41% and 0.36% (P < .01). CONCLUSION: When controlled for sample order, the sensitivity of thin-layer cytology for detecting high grade CIN was significantly higher than that of conventional smears in patients with previous abnormal cytology, but at the expense of specificity.


Subject(s)
Histocytological Preparation Techniques/methods , Uterine Cervical Dysplasia/pathology , Uterine Cervical Neoplasms/pathology , Vaginal Smears/methods , Biopsy/methods , Cervix Uteri/pathology , Cervix Uteri/surgery , Female , Humans , Sensitivity and Specificity , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Dysplasia/diagnosis
16.
Article in French | MEDLINE | ID: mdl-3027158

ABSTRACT

There is no consistency in the treatment of dysplasias of the cervix of the uterus. It varies from team to team and there is no criterion that points with any certainty to how the lesion will develop--whether it will become worse, whether it will persist as it is or whether it will regress. For the first time there is an objective factor, namely typing of the papillomavirus by molecular hybridisation. The presence of HPV 16, 18 or 33 is prognostically bad. Active treatment should be instituted. In the other cases "armed surveillance" or destroying the lesions is sufficient. This is particularly important in young women who wish to have a family.


Subject(s)
Papillomaviridae/isolation & purification , Uterine Cervical Dysplasia/microbiology , Adult , Female , Humans , Papillomaviridae/classification , Uterine Cervical Dysplasia/therapy
17.
Nat Prod Commun ; 9(8): 1179-80, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25233603

ABSTRACT

From Usnea aciculifera, a new depside aciculiferin A (1) was isolated, together with eleven known compounds, (+)-(12R)-usnic acid (2), methyl haematommate (3), methyl beta-orsellinate (4), methyl orsellinate (5), atranol (6), 7-hydroxy-5-methoxy-6-methylphthalide (7), norstictic acid (8), stictic acid (9), atranorin (10), barbatinic acid (11) and diffractaic acid (12). Their chemical structures were elucidated by 1D and 2D NMR spectroscopic as well as HR-ESI-MS analysis. Usnic acid (2) and depside diffractaic acid (12) presented in high yield of around 1.5% of the dried material. Some lichen substances inhibited the growth of some cancer cell lines. Three depsides, 1, 11 and 12, were evaluated for their cytotoxic activity against HeLa (human epithelial carcinoma), NCI-H460 (human lung cancer) and MCF-7 (human breast cancer) cell lines at the concentration of 100 microg/mL. Depside 1 showed good and depside 12 strong cytotoxic activity against three surveyed cancer cell lines.


Subject(s)
Ascomycota/chemistry , Depsides/chemistry , Depsides/pharmacology , Pinus/microbiology , Ascomycota/growth & development , Ascomycota/isolation & purification , Cell Line , Cell Proliferation/drug effects , Depsides/isolation & purification , Humans , Magnetic Resonance Spectroscopy , Molecular Structure , Vietnam
18.
J Gynecol Obstet Biol Reprod (Paris) ; 42(5): 464-72, 2013 Sep.
Article in French | MEDLINE | ID: mdl-23747216

ABSTRACT

OBJECTIVES: The main objective of this study was to compare the performances of polarimetric imaging and standard colposcopy for the detection of CIN. MATERIALS AND METHODS: We performed a monocentric prospective clinical study. The standard colposcopic diagnosis obtained during a first consultation was compared to the diagnosis provided by polarimetric imaging in a second consultation. In addition to the biopsies guided by classical or polarimetric colposcopy, a systematic biopsy taken at a predefined location allowed to calculate the specificities and sensitivities of both techniques. RESULTS: One hundred and forty-one patients were included, all of them with anomalous Pap smears. Sixty-seven cone biopsies were taken, 69 % of which were eventually diagnosed with CIN2+ lesions. The sensitivities and specificities were found to be equal for standard and polarimetric colposcopies. CONCLUSION: We could not demonstrate any improvement of the diagnostic performances with polarimetric colposcopy alone. However, for both healthy and pathological cervices, we observed interesting polarimetric responses involving other characteristics than those we initially assumed, and which will be taken into account in a future study.


Subject(s)
Colposcopy/instrumentation , Colposcopy/methods , Uterine Cervical Dysplasia/diagnosis , Uterine Cervical Dysplasia/pathology , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/pathology , Adult , Aged , Biopsy , Conization/instrumentation , Conization/methods , Female , Humans , Middle Aged , Optical Devices , Parity , Pregnancy , Uterine Cervical Neoplasms/epidemiology , Young Adult , Uterine Cervical Dysplasia/epidemiology
19.
Gynecol Obstet Fertil ; 40(7-8): 406-10, 2012.
Article in French | MEDLINE | ID: mdl-22727741

ABSTRACT

OBJECTIVES: Human Papillomaviruses (HPV) infection is high in heterosexual couples. We have evaluated clinically the frequency and the histological type of genital lesions in men whose partners have an HPV cervical and/or external genital lesion. PATIENTS AND METHODS: We conducted a cross-sectional study; we examined 246 men whose partner was referred for HPV lesions treatment of either the external genital tract or the cervix. All clinical HPV lesions detected in the men then underwent histological examination. RESULTS: In 72% of cases, the couples were 18 to 35 years old. We detected HPV clinical lesions, confirmed histologically in 43% (106/246) of men. Warts and high-grade intraepithelial neoplasia were diagnosed in 83 (78%) and 23 (22%) of cases, respectively. The prevalence of clinical HPV lesions in men ranged from 34% in case of HG CIN to 80% when the female partner suffered from genital warts. DISCUSSION AND CONCLUSIONS: The high frequency of clinical HPV lesions in men whose the partner has warts should lead to a peniscopy of the partner in these cases. Similarly, the peniscopy detects an HPV lesion in a third of men of which the partner gets a HG CIN. It is necessary to realize prospective studies to reevaluate the impact of diagnosing and treating male lesions with regard to the evolution of HG CIN in their partner.


Subject(s)
Papillomavirus Infections/epidemiology , Adenocarcinoma/epidemiology , Adenocarcinoma/pathology , Adenocarcinoma/virology , Adolescent , Adult , Carcinoma in Situ/epidemiology , Carcinoma in Situ/pathology , Carcinoma in Situ/virology , Condylomata Acuminata/epidemiology , Condylomata Acuminata/pathology , Condylomata Acuminata/virology , Cross-Sectional Studies , Family Characteristics , Female , France/epidemiology , Genital Neoplasms, Male/epidemiology , Genital Neoplasms, Male/pathology , Genital Neoplasms, Male/virology , Heterosexuality/statistics & numerical data , Humans , Male , Middle Aged , Papillomavirus Infections/pathology , Prevalence , Young Adult
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