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1.
J Assist Reprod Genet ; 37(4): 777-787, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32026202

ABSTRACT

PURPOSE: In men, obesity may lead to poor semen parameters and reduced fertility. However, the causative links between obesity and male infertility are not totally clear, particularly on a molecular level. As such, we investigated how obesity modifies the human sperm proteome, to elucidate any important implications for fertility. METHODS: Sperm protein lysates from 5 men per treatment, classified as a healthy weight (body mass index (BMI) ≤ 25 kg/m2) or obese (BMI ≥ 30 kg/m2), were FASP digested, submitted to liquid chromatography tandem mass spectrometry, and compared by label-free quantification. Findings were confirmed for several proteins by qualitative immunofluorescence and a quantitative protein immunoassay. RESULTS: A total of 2034 proteins were confidently identified, with 24 proteins being significantly (p < 0.05) less abundant (fold change < 0.05) in the spermatozoa of obese men and 3 being more abundant (fold change > 1.5) compared with healthy weight controls. Proteins with altered abundance were involved in a variety of biological processes, including oxidative stress (GSS, NDUFS2, JAGN1, USP14, ADH5), inflammation (SUGT1, LTA4H), translation (EIF3F, EIF4A2, CSNK1G1), DNA damage repair (UBEA4), and sperm function (NAPA, RNPEP, BANF2). CONCLUSION: These results suggest that oxidative stress and inflammation are closely tied to reproductive dysfunction in obese men. These processes likely impact protein translation and folding during spermatogenesis, leading to poor sperm function and subfertility. The observation of these changes in obese men with no overt andrological diagnosis further suggests that traditional clinical semen assessments fail to detect important biochemical changes in spermatozoa which may compromise fertility.


Subject(s)
Fertility/genetics , Obesity/genetics , Proteome/genetics , Spermatogenesis/genetics , Adult , Body Mass Index , Female , Humans , Infertility, Male/complications , Infertility, Male/genetics , Infertility, Male/metabolism , Infertility, Male/pathology , Male , Obesity/complications , Obesity/pathology , Oxidative Stress/genetics , Proteome/metabolism , Semen Analysis , Sperm Count , Sperm Motility/genetics , Spermatozoa/metabolism , Spermatozoa/pathology
2.
Astron Astrophys ; 6302019 Oct.
Article in English | MEDLINE | ID: mdl-32699429

ABSTRACT

CONTEXT: Pre-equinox measurements of comet 67P/Churyumov-Gerasimenko with the mass spectrometer ROSINA/DFMS on board the Rosetta spacecraft revealed a strongly heterogeneous coma. The abundances of major and various minor volatile species were found to depend on the latitude and longitude of the nadir point of the spacecraft. The observed time variability of coma species remained consistent for about three months up to equinox. The chemical variability could be generally interpreted in terms of surface temperature and seasonal effects superposed on some kind of chemical heterogeneity of the nucleus. AIMS: We compare here pre-equinox (inbound) ROSINA/DFMS measurements from 2014 to measurements taken after the outbound equinox in 2016, both at heliocentric distances larger than 3 AU. For a direct comparison we limit our observations to the southern hemisphere. METHODS: We report the similarities and differences in the concentrations and time variability of neutral species under similar insolation conditions (heliocentric distance and season) pre- and post-equinox, and interpret them in light of the previously published observations. In addition, we extend both the pre- and post-equinox analysis by comparing species concentrations with a mixture of CO2 and H2O. RESULTS: Our results show significant changes in the abundances of neutral species in the coma from pre- to post-equinox that are indicative of seasonally driven nucleus heterogeneity. CONCLUSIONS: The observed pre- and post-equinox patterns can generally be explained by the strong erosion in the southern hemisphere that moves volatile-rich layers near the surface.

3.
Science ; 356(6342): 1069-1072, 2017 06 09.
Article in English | MEDLINE | ID: mdl-28596364

ABSTRACT

The origin of cometary matter and the potential contribution of comets to inner-planet atmospheres are long-standing problems. During a series of dedicated low-altitude orbits, the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) on the Rosetta spacecraft analyzed the isotopes of xenon in the coma of comet 67P/Churyumov-Gerasimenko. The xenon isotopic composition shows deficits in heavy xenon isotopes and matches that of a primordial atmospheric component. The present-day Earth atmosphere contains 22 ± 5% cometary xenon, in addition to chondritic (or solar) xenon.

4.
Nature ; 526(7575): 678-81, 2015 Oct 29.
Article in English | MEDLINE | ID: mdl-26511578

ABSTRACT

The composition of the neutral gas comas of most comets is dominated by H2O, CO and CO2, typically comprising as much as 95 per cent of the total gas density. In addition, cometary comas have been found to contain a rich array of other molecules, including sulfuric compounds and complex hydrocarbons. Molecular oxygen (O2), however, despite its detection on other icy bodies such as the moons of Jupiter and Saturn, has remained undetected in cometary comas. Here we report in situ measurement of O2 in the coma of comet 67P/Churyumov-Gerasimenko, with local abundances ranging from one per cent to ten per cent relative to H2O and with a mean value of 3.80 ± 0.85 per cent. Our observations indicate that the O2/H2O ratio is isotropic in the coma and does not change systematically with heliocentric distance. This suggests that primordial O2 was incorporated into the nucleus during the comet's formation, which is unexpected given the low upper limits from remote sensing observations. Current Solar System formation models do not predict conditions that would allow this to occur.


Subject(s)
Meteoroids , Oxygen/analysis , Carbon Monoxide/analysis , Extraterrestrial Environment/chemistry , Ice/analysis , Nitrogen/analysis , Oxygen/radiation effects , Photolysis , Solar System/chemistry , Spacecraft , Water/analysis
5.
J Thromb Haemost ; 13(10): 1878-87, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26256459

ABSTRACT

BACKGROUND: Systemic hyperfibrinolysis is a lethal phenotype of trauma-induced coagulopathy. Its pathogenesis is poorly understood. Recent studies have support a central role of platelets in hemostasis and in fibrinolysis regulation, implying that platelet impairment is integral to the development of postinjury systemic hyperfibrinolysis. OBJECTIVE: The objective of this study was to identify if platelet function is associated with blood clot sensitivity to fibrinolysis. We hypothesize that platelet impairment of the ADP pathway correlates with fibrinolysis sensitivity in trauma patients. METHODS: A prospective observational study of patients meeting the criteria for the highest level of activation at an urban trauma center was performed. Viscoelastic parameters associated with platelet function (maximum amplitude [MA]) were measured with native thrombelastography (TEG), and TEG platelet mapping of the ADP pathway (ADP-MA). The contribution of fibrinogen to clotting was measured with TEG (angle) and the TEG functional fibrinogen (FF) assay (FF-MA). Another TEG assay containing tissue-type plasminogen activator (t-PA) (75 ng mL(-1) ) was used to assess clot sensitivity to an exogenous fibrinolytic stimulus by use of the TEG lysis at 30 min (LY30) variable. Multivariate linear regression was used to identify which TEG variable correlated with t-PA-LY30 (quantification of fibrinolysis sensitivity). RESULTS: Fifty-eight trauma patients were included in the analysis, with a median injury severity score of 17 and a base deficit of 6 mEq L(-1) . TEG parameters that significantly predicted t-PA-LY30 were related to platelet function (ADP-MA, P = 0.001; MA, P < 0.001) but not to fibrinogen (FF-MA, P = 0.773; angle, P = 0.083). Clinical predictors of platelet ADP impairment included calcium level (P = 0.001), base deficit (P = 0.001), and injury severity (P = 0.001). RESULTS AND CONCLUSIONS: Platelet impairment of the ADP pathway is associated with increased sensitivity to t-PA. ADP pathway inhibition in platelets may be an early step in the pathogenesis of systemic hyperfibrinolysis.


Subject(s)
Blood Platelets/drug effects , Fibrinogen/metabolism , Fibrinolysis/drug effects , Fibrinolytic Agents/therapeutic use , Platelet Function Tests , Thrombolytic Therapy/methods , Tissue Plasminogen Activator/therapeutic use , Wounds and Injuries/drug therapy , Adenosine Diphosphate/blood , Adult , Biomarkers/blood , Blood Platelets/metabolism , Blood Viscosity , Calcium/blood , Elasticity , Female , Humans , Injury Severity Score , Linear Models , Male , Middle Aged , Multivariate Analysis , Patient Selection , Predictive Value of Tests , Prospective Studies , Treatment Outcome , Wounds and Injuries/blood , Wounds and Injuries/diagnosis
6.
Science ; 348(6231): 232-5, 2015 Apr 10.
Article in English | MEDLINE | ID: mdl-25791084

ABSTRACT

Molecular nitrogen (N2) is thought to have been the most abundant form of nitrogen in the protosolar nebula. It is the main N-bearing molecule in the atmospheres of Pluto and Triton and probably the main nitrogen reservoir from which the giant planets formed. Yet in comets, often considered the most primitive bodies in the solar system, N2 has not been detected. Here we report the direct in situ measurement of N2 in the Jupiter family comet 67P/Churyumov-Gerasimenko, made by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis mass spectrometer aboard the Rosetta spacecraft. A N2/CO ratio of (5.70 ± 0.66) × 10(-3) (2σ standard deviation of the sampled mean) corresponds to depletion by a factor of ~25.4 ± 8.9 as compared to the protosolar value. This depletion suggests that cometary grains formed at low-temperature conditions below ~30 kelvin.

7.
Science ; 347(6220): aaa0276, 2015 Jan 23.
Article in English | MEDLINE | ID: mdl-25613892

ABSTRACT

Comets contain the best-preserved material from the beginning of our planetary system. Their nuclei and comae composition reveal clues about physical and chemical conditions during the early solar system when comets formed. ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) onboard the Rosetta spacecraft has measured the coma composition of comet 67P/Churyumov-Gerasimenko with well-sampled time resolution per rotation. Measurements were made over many comet rotation periods and a wide range of latitudes. These measurements show large fluctuations in composition in a heterogeneous coma that has diurnal and possibly seasonal variations in the major outgassing species: water, carbon monoxide, and carbon dioxide. These results indicate a complex coma-nucleus relationship where seasonal variations may be driven by temperature differences just below the comet surface.

8.
Vox Sang ; 108(2): 131-40, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25200932

ABSTRACT

BACKGROUND AND OBJECTIVES: The safety and efficacy of stored red blood cells (RBCs) transfusion has been long debated due to retrospective clinical evidence and laboratory results, indicating a potential correlation between increased morbidity and mortality following transfusion of RBC units stored longer than 14 days. We hypothesize that storage in Optisol additive solution-5 leads to a unique metabolomics profile in the supernatant of stored RBCs. MATERIALS AND METHODS: Whole blood was drawn from five healthy donors, RBC units were manufactured, and prestorage leucoreduced by filtration. Samples were taken on days 1 and 42, the cells removed, and mass spectrometry-based metabolomics was performed. RESULTS: The results confirmed the progressive impairment of RBC energy metabolism by day 42 with indirect markers of a parallel alteration of glutathione and NADPH homeostasis. Moreover, oxidized pro-inflammatory lipids accumulated by the end of storage. CONCLUSION: The supernatants from stored RBCs may represent a burden to the transfused recipients from a metabolomics standpoint.


Subject(s)
Blood Preservation/methods , Erythrocytes/metabolism , Metabolome , Erythrocyte Transfusion/methods , Humans , Mass Spectrometry , Retrospective Studies
9.
Science ; 347(6220): 1261952, 2015 Jan 23.
Article in English | MEDLINE | ID: mdl-25501976

ABSTRACT

The provenance of water and organic compounds on Earth and other terrestrial planets has been discussed for a long time without reaching a consensus. One of the best means to distinguish between different scenarios is by determining the deuterium-to-hydrogen (D/H) ratios in the reservoirs for comets and Earth's oceans. Here, we report the direct in situ measurement of the D/H ratio in the Jupiter family comet 67P/Churyumov-Gerasimenko by the ROSINA mass spectrometer aboard the European Space Agency's Rosetta spacecraft, which is found to be (5.3 ± 0.7) × 10(-4)­that is, approximately three times the terrestrial value. Previous cometary measurements and our new finding suggest a wide range of D/H ratios in the water within Jupiter family objects and preclude the idea that this reservoir is solely composed of Earth ocean-like water.

10.
Vox Sang ; 105(3): 210-8, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23663258

ABSTRACT

BACKGROUND: Red blood cell (RBC) transfusion is a life-saving intervention for critically ill patients; however, it has been linked to increased morbidity and mortality. We hypothesize that a number of important proteins accumulate during routine storage of RBCs, which may explain some of the adverse effects seen in transfused patients. STUDY DESIGN: Five RBC units were drawn and divided (half prestorage leucoreduced (LR-RBC) and half left as an unmodified control (RBC). The supernatant was separated on days 1 and 42 of storage and proteomic analyses completed with in-gel tryptic digestion and nano-liquid chromatography tandem mass spectrometry. RESULTS: In RBC supernatants, 401 proteins were identified: 203 increased with storage, 114 decreased, and 84 were unchanged. In LR-RBC supernatant, 231 proteins were identified: 84 increased with storage, 30 decreased, and 117 were unchanged. Prestorage leucoreduction removed many platelet- and leucocyte-derived structural proteins; however, a number of intracellular proteins accumulated including peroxiredoxins (Prdx) 6 and latexin. The increases were confirmed by immunoblotting, including the T-phosphorylation of Prdx-6, indicating that it may be functioning as an active phospholipase. Active matrix metalloproteinase-9 also increased with a coinciding decrease in the metalloproteinase inhibitor 1 and cystatin C. CONCLUSION: We conclude that a number of proteins increase with RBC storage, which is partially ameliorated with leucoreduction, and transfusion of stored RBCs may introduce mediators that result in adverse events in the transfused host.


Subject(s)
Blood Preservation/adverse effects , Blood Proteins/analysis , Erythrocytes/chemistry , Blood Platelets/chemistry , Blood Platelets/cytology , Critical Illness/therapy , Erythrocyte Transfusion/adverse effects , Female , Humans , Leukocyte Count , Leukocytes/chemistry , Leukocytes/cytology , Male , Mass Spectrometry , Proteomics , Time Factors
11.
Eur J Appl Physiol ; 112(11): 3775-85, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22382668

ABSTRACT

Aerobic exercise increases 24-h fat oxidation following initiation of a high-fat diet. The objective of this study is to examine the time course of increased fat oxidation under exercise and sedentary conditions. Eighteen healthy subjects completed a randomized crossover design (sedentary and exercise visits) staying for five consecutive days in a metabolic chamber each visit. On day 1, 30% of energy intake was from fat; days 2-5 had 50% of energy as fat. During exercise, subjects rode on a stationary cycle at 45% of VO2max for 1 h in the mornings and evenings. Respiratory gases and urinary nitrogen were collected to calculate macronutrient oxidation and non-protein respiratory exchange ratio (NPRER). This data, collected continuously (24-h periods), were subsequently divided into three time segments: (1) exercise + recovery (1000-1200 hours, 2100-2200 hours), (2) sleep (2300-0645 hours), and (3) wake (all remaining hours). NPRER on exercise versus sedentary visits was lower for the sleep segment (0.77 ± 0.01 01 vs. 0.81 ± 0.01, p < 0.001), higher for the exercise + recovery segment (0.88 ± 0.01 vs. 0.86 ± 0.01, p < 0.001), and was not different for the wake segment. Fat oxidation was significantly higher for exercise versus sedentary treatments during sleep (41 ± 2 vs. 31 ± 2 g), wake (62 ± 3 vs. 51 ± 3 g), and exercise + recovery segments (33 ± 3 vs.16 ± 1 g), but so was fat intake by design (171 ± 8 vs. 128 ± 7 g/d). Although exercise showed greater fat oxidation during all segments, dietary fat intake was also higher. Therefore, based on NPRER, the time of day during which the exercise treatment increased the ratio of fat to carbohydrate oxidation was during sleep.


Subject(s)
Circadian Rhythm/physiology , Diet, High-Fat , Energy Intake/physiology , Exercise/physiology , Adipose Tissue , Adolescent , Adult , Female , Humans , Male , Middle Aged , Oxidation-Reduction , Oxygen Consumption
12.
Clin Exp Allergy ; 39(7): 1099-108, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19438581

ABSTRACT

RATIONALE: An important property of allergens is their ability to cross-link IgE and activate mast cells and basophils. The effector activity of peanut allergens has not been well characterized. METHODS: Crude extracts of fresh peanut flour were fractionated by gel filtration. Effector function was assayed by measuring degranulation of RBL SX-38 cells sensitized with IgE from individual sera and from pools of sera of peanut-allergic donors. RESULTS: Following gel filtration, 75 +/- 7% of the applied protein and 76 +/- 16% (n=3) of the applied activity (assayed with a pool of 11 sera) were recovered in the resultant fractions. The majority (85 +/- 2%; n=3) of the recovered activity resided in a fraction with a theoretical average molecular weight of approximately 20 kDa and a range of 13-25 kDa. When all the individual fractions were recombined, the measured activity was similar to that of the original extract [140 +/- 43% when measured with a pool of serum (n=2) and 66 +/- 7% when measured with individual sera (n=4)]; when all individual fractions excluding the 20 kDa fraction were recombined, the measured activity was only 8 +/- 2% (n=2) of the original extract when assayed with the serum pool and 10 +/- 4% (n=3) when assayed with the individual sera. Two-dimensional gel electrophoresis of this biologically active fraction revealed >60 protein spots. Analysis of 50 of the most prominent spots by matrix-assisted laser-desorption ionization time-of-flight mass spectrometry and of the full mixture by automated tandem mass spectrometry coupled to online capillary liquid chromatography revealed that >97% of the protein mass consisted of Ara h 2.0101, Ara h 2.0201, Ara h 6 isoforms, and variants of these proteins. CONCLUSIONS: Ara h 2 and Ara h 6 account for the majority of the effector activity found in a crude peanut extract.


Subject(s)
2S Albumins, Plant/immunology , Allergens/immunology , Antigens, Plant/immunology , Arachis/chemistry , Arachis/immunology , Glycoproteins/immunology , Immunoglobulin E/immunology , Peanut Hypersensitivity/immunology , 2S Albumins, Plant/chemistry , 2S Albumins, Plant/isolation & purification , Allergens/chemistry , Allergens/isolation & purification , Antigens, Plant/chemistry , Antigens, Plant/isolation & purification , Chromatography, Gel , Chromatography, Liquid , Electrophoresis, Gel, Two-Dimensional , Glycoproteins/chemistry , Glycoproteins/isolation & purification , Humans , Immunoblotting , Immunoglobulin E/blood , Mast Cells/cytology , Mast Cells/immunology , Molecular Weight , Peanut Hypersensitivity/blood , Reproducibility of Results , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Tandem Mass Spectrometry
13.
Clin Exp Allergy ; 37(5): 752-63, 2007 May.
Article in English | MEDLINE | ID: mdl-17456223

ABSTRACT

BACKGROUND: Ara h 2 is a potent peanut allergen but its contribution to the ability of a crude peanut extract (CPE) to cross-link IgE and activate mast cells has not been rigorously evaluated. OBJECTIVE: To measure the contribution that Ara h 2 makes to the effector function of a CPE. METHODS: Ara h 2 was specifically removed from a CPE as demonstrated by immunoblots, 2D gels, and an inhibitory ELISA. Functional assays of sham-treated and Ara h 2-depleted CPEs were performed with RBL SX-38 cells sensitized with IgE from highly peanut-allergic subjects and with naturally sensitized basophils. RESULTS: Depletion of approximately 99% of the Ara h 2 from the CPE led to an increase in the concentration of the CPE necessary to give 50% of maximal degranulation (EC50) of the SX-38 cells following sensitization with sera that contain anti-Ara h 2 IgE. Assays with a pool of 10 sera showed a small but significant increase in the EC50 following depletion of Ara h 2 (1.65+/-0.15-fold; P<0.05) and assays of seven individual sera showed a similar increase in the average EC50 (1.7+/-0.2-fold; P<0.02). The percent of the anti-peanut IgE that binds Ara h 2 correlated with an increase in the EC50 of the CPE following depletion of Ara h 2 (r=0.83; P<0.02). On the other hand, data from three of these patients studied with a basophil histamine release assay did not show a significant effect of depletion of Ara h 2. CONCLUSION: Based on its ability to cross-link IgE effectively, Ara h 2 is clearly an important peanut allergen. Its ability to cross-link IgE effectively from a specific serum is related to the proportion of anti-Ara h 2 in that serum but Ara h 2 does not account for a majority of the effector activity of the CPE for any of the sera studied.


Subject(s)
Allergens/immunology , Arachis/immunology , Glycoproteins/immunology , Immunoglobulin E/immunology , Peanut Hypersensitivity/immunology , Plant Proteins/immunology , 2S Albumins, Plant , Adolescent , Adult , Aged , Allergens/analysis , Antigens, Plant , Basophil Degranulation Test , Basophils/immunology , Child , Child, Preschool , Electrophoresis, Gel, Two-Dimensional/methods , Humans , Immunoglobulin E/blood , Mast Cells/immunology , Middle Aged , Plant Extracts/immunology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
14.
Nature ; 433(7027): 720-2, 2005 Feb 17.
Article in English | MEDLINE | ID: mdl-15716946

ABSTRACT

The interaction of the solar wind with Earth's magnetosphere gives rise to the bright polar aurorae and to geomagnetic storms, but the relation between the solar wind and the dynamics of the outer planets' magnetospheres is poorly understood. Jupiter's magnetospheric dynamics and aurorae are dominated by processes internal to the jovian system, whereas Saturn's magnetosphere has generally been considered to have both internal and solar-wind-driven processes. This hypothesis, however, is tentative because of limited simultaneous solar wind and magnetospheric measurements. Here we report solar wind measurements, immediately upstream of Saturn, over a one-month period. When combined with simultaneous ultraviolet imaging we find that, unlike Jupiter, Saturn's aurorae respond strongly to solar wind conditions. But in contrast to Earth, the main controlling factor appears to be solar wind dynamic pressure and electric field, with the orientation of the interplanetary magnetic field playing a much more limited role. Saturn's magnetosphere is, therefore, strongly driven by the solar wind, but the solar wind conditions that drive it differ from those that drive the Earth's magnetosphere.

16.
Biochim Biophys Acta ; 1456(2-3): 121-37, 2000 Jan 10.
Article in English | MEDLINE | ID: mdl-10627300

ABSTRACT

In order to probe the reaction chemistry of respiratory quinol-oxidizing enzymes on a rapid time scale, a photoreleasable quinol substrate was synthesized by coupling decylubiquinol with the water-soluble protecting group 3',5'-bis(carboxymethoxy)benzoin (BCMB) through a carbonate linkage. The resulting compound, DQ-BCMB, was highly soluble in aqueous detergent solution, and showed no reactivity with quinol-oxidizing enzymes prior to photolysis. Upon photolysis in acetonitrile, 5, 7-bis(carboxymethoxy)-2-phenylbenzofuran, carbon dioxide, and decylubiquinol were formed. In aqueous media, free 3', 5'-bis(carboxymethoxy)benzoin was also produced. Photolysis of DQ-BCMB with a 308 nm excimer laser led to the release of the BCMB group in less than 10(-6) s. Decylubiquinol was released in the form of a carbonate monoester, which decarboxylated with an observed first-order rate constant of 195-990 s(-1), depending on the reaction medium. Yields of decylubiquinol as high as 35 microM per laser pulse were attained readily. In the presence of Escherichia coli cytochrome bo(3), photolysis of DQ-BCMB led to the oxidation of quinol by the enzyme with a rate that was limited by the rate of the decylubiquinol release. Mitochondrial cytochrome bc(1) reacted with photoreleased decylubiquinol with distinct kinetic phases corresponding to rapid b heme reduction and somewhat slower c heme reduction. Oxidation of photoreleased ubiquinol by this enzyme showed saturation kinetics with a K(m) of 3.6 microM and a k(cat) of 210 s(-1). The saturation behavior was a result of decylubiquinol being released as a carbonate monoester during the photolysis of DQ-BCMB and interacting with cytochrome bc(1) before decarboxylation of this intermediate yielded free decylubiquinol. The reaction of cytochrome bc(1) and photoreleased decylubiquinol in the presence of antimycin A led to monophasic b heme reduction, but also yielded slower quinol oxidation kinetics. The discrimination of kinetic phases in the reaction of cytochrome bc(1) with ubiquinol substrates has provided a means of exploring the bifurcation of electron transfer that is central to the operation of the Q-cycle in this enzyme.


Subject(s)
Cytochromes/metabolism , Electron Transport Complex III/metabolism , Escherichia coli/enzymology , Mitochondria/enzymology , Ubiquinone/analogs & derivatives , Cytochrome b Group , Electron Transport , Escherichia coli Proteins , Hydrogen-Ion Concentration , Nuclear Magnetic Resonance, Biomolecular , Photochemistry , Ubiquinone/metabolism
17.
Gynecol Oncol ; 57(1): 66-71, 1995 Apr.
Article in English | MEDLINE | ID: mdl-7705702

ABSTRACT

The relation between eight specific colposcopic diagnostic findings and the histologic grade of a cervical lesion in 896 women was evaluated. The size of the transformation zone (TZ), the size of the lesion, the intensity of the color tone, distinct margins, the pathology of the vessels, and the presence of micropapillae as single findings were highly statistically correlated to the histologic grade (P < 0.0001). By logistic regression analysis the risk for a higher histologic grade when assessed by colposcopy was greatest in women with variation of the acetowhite color (odds ratio (OR) = 16.0; 95% CI, 10.0-26.0) followed by coarse vessels (OR = 10.0; CI, 3.2-34.0). Lesion-size larger than 50% of the visible cervix had an OR of 3.6 (CI, 2.1-6.3). Extention beyond TZ had an OR of 0.4 (CI, 0.2-0.4) and larger TZ had an OR of 0.5 (CI, 0.3-0.9). In conclusion we found that the size of the cervical lesion had some independent predictive value and should be considered in future trials.


Subject(s)
Cervix Uteri/pathology , Uterine Cervical Neoplasms/pathology , Adolescent , Adult , Aged , Biopsy , Cell Transformation, Neoplastic/pathology , Colposcopy , Female , Humans , Middle Aged , Odds Ratio , Predictive Value of Tests , Regression Analysis , Uterine Cervical Neoplasms/diagnosis
18.
Acta Obstet Gynecol Scand ; 73(8): 648-51, 1994 Sep.
Article in English | MEDLINE | ID: mdl-7941991

ABSTRACT

OBJECTIVE: To evaluate the diagnostic accuracy of cytology and colposcopy in women with an abnormal cervical smear using histology as the 'gold standard'. DESIGN: Survey of consecutively referred women with abnormal smear. SETTING: The out-patient colposcopical clinic of Herning Hospital, Denmark. PATIENTS: 813 women with a median age of 29.0 years (range 15-71 years) with their first abnormal smear. RESULTS: For detecting cervical high-grade lesions (HGL) the sensitivity of cytology was 41% (36-47%), of colposcopy 67% (62-72%) and in combination 75% (70-80%), so at least 25% of HGL were underestimated. Colposcopy underestimated more CIN-2 than CIN-3 lesions and more small lesions and lesions in smaller transformation zones. Cytology underestimated more CIN-2 lesions but equal numbers of small and large lesions and transformation zones. CONCLUSIONS: Colposcopy was a better tool for diagnosing HGL than cytology, but even in combination too many HGL were missed. All women with abnormal cytology should therefore have colposcopical and histological investigation and prospective studies of the natural history of cervical squamous lesions should include histological evidence.


Subject(s)
Carcinoma, Squamous Cell/diagnosis , Uterine Cervical Dysplasia/diagnosis , Adolescent , Adult , Aged , Carcinoma, Squamous Cell/pathology , Colposcopy , Diagnosis, Differential , Female , Humans , Middle Aged , Vaginal Smears , Uterine Cervical Dysplasia/pathology
19.
Ugeskr Laeger ; 156(4): 471-3, 1994 Jan 24.
Article in Danish | MEDLINE | ID: mdl-8140664

ABSTRACT

In 1986 The National Board of Health published guidelines for cervical cancer screening in Denmark. These guidelines recommend organized screening with personal invitations every three years to women in the age group 23-59 years, and in the years to come also invitation of women aged 60-74 years. We studied the organization of cervical cancer screening in Danish counties at the beginning of 1994. Organized screening programmes are running in 15 out of the 16 "counties" (this include the municipalities of København and Frederiksberg). Four counties completely follow the national guidelines. Eight counties follow these guidelines in general, but they do not invite women above the age of 60 years. In total, 72% of women aged 25-74 years are at present invited for cervical cancer screening in Denmark.


Subject(s)
Mass Screening/trends , Uterine Cervical Neoplasms/prevention & control , Adult , Aged , Denmark , Female , Humans , Mass Screening/organization & administration , Middle Aged , Vaginal Smears
20.
Ugeskr Laeger ; 154(19): 1339-42, 1992 May 04.
Article in Danish | MEDLINE | ID: mdl-1598707

ABSTRACT

In 1986, The Danish National Board of Health published guidelines for cervical cancer screening. These guidelines recommend organized screening with personal invitations every three years to women in the age group 23-59 years, and in the years to come also invitations to women aged 60-74 years. Five years have now elapsed since publication of these guidelines, and we have therefore studied the present organization of cervical cancer screening in Danish counties. Organized screening programmes are now, medio 1991, running in 11 out of the 16 "counties" (this includes the municipalities of Copenhagen and Frederiksberg). One county follows the national guidelines entirely. Six counties follow these guidelines in general, but they do not invite women over the age of 60 years. In all, 45% of women aged 25-74 years are at present invited for cervical cancer screening in Denmark. Two counties have decided to start organized screening programmes in 1992.


Subject(s)
Mass Screening/organization & administration , Uterine Cervical Neoplasms/prevention & control , Adult , Denmark/epidemiology , Female , Humans , Middle Aged , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/epidemiology
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