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1.
Urologe A ; 59(5): 544-549, 2020 May.
Article in German | MEDLINE | ID: mdl-32274543

ABSTRACT

The diagnosis and treatment of lower urinary tract symptoms (LUTS) due to benign prostatic enlargement plays an important role in daily urological practice. Therefore, a targeted and resource-saving approach is essential. A rational base-line work-up of our patients provides the necessary information for obtaining the diagnosis and only needs to be expanded in individual cases. In addition to drug therapy, the modification of lifestyle and the possibility of watchful waiting must not be underestimated. Simple measures such as a timed fluid intake, double micturition in the case of residual urine development, but also bladder reconditioning can significantly improve the quality of life of our patients. Regarding surgical treatment, laser procedures have found their way into many departments and have established themselves in daily routine as a reference procedure in addition to transurethral resection of the prostate (TUR-P) and simple open prostatectomy. New, minimally invasive procedures-such as prostatic artery embolization (PAE), the Rezum™- (NxThera Inc., Maple-Grove, MN, USA) or the Aquabeam® (Procept, Redwood City, CA, USA) procedure, but also nonablative procedures such as iTind© (TIND, Medi-Tate, Or Akiva, Israel) or Urolift® (Neotract Inc., Pleasanton, CA, USA)-offer new treatment options to those affected, with the potential to maintain patient's sexual function. As a result, individual risk assessment and advice on the advantages and disadvantages of all available treatment options-even more than today-will be an important part of LUTS treatment. An individual approach, similar to that used in the treatment of oncological disease, will become standard also in the treatment of benign prostatic syndrome.


Subject(s)
Embolization, Therapeutic , Lower Urinary Tract Symptoms/therapy , Practice Guidelines as Topic , Prostatic Hyperplasia/therapy , Transurethral Resection of Prostate/standards , Humans , Lower Urinary Tract Symptoms/diagnosis , Lower Urinary Tract Symptoms/physiopathology , Male , Prostatic Hyperplasia/diagnosis , Prostatic Hyperplasia/physiopathology , Quality of Life , Transurethral Resection of Prostate/adverse effects , Treatment Outcome
2.
BMC Nephrol ; 19(1): 241, 2018 09 20.
Article in English | MEDLINE | ID: mdl-30236081

ABSTRACT

BACKGROUND: Anti-glomerular basement-membrane (anti-GBM) disease (or Goodpasture disease) is characterized by severe kidney and lung involvement. Prognoses have improved with treatments that combine plasma exchange and immunosuppressive drugs. However, patients with severe renal involvement can have poor renal outcomes and cyclophosphamide can cause significant complications. Anti-GBM antibodies have a direct pathogenic effect on the disease: thus, therapeutics that can decrease their production, such as rituximab, could be a good alternative. METHODS: The medical files of five patients that had received rituximab as a first-line therapy (instead of cyclophosphamide), plus plasma exchange and steroids, were reviewed. All patients had severe disease manifestations. RESULTS: Four patients required dialysis at diagnosis and remained dialysis-dependent over the mean follow-up of 15 months. Three patients had pulmonary involvement, but recovered even though mechanical ventilation was required. Anti-GBM antibodies became rapidly undetectable in all patients. One infectious and two hematological complications were observed. CONCLUSIONS: We report the outcomes of five patients with Goodpasture disease and treated with rituximab as a first-line treatment. This strategy was effective at treating pulmonary manifestations and was associated with a good biological response with no major serious adverse events. However, renal outcomes were not significantly improved.


Subject(s)
Anti-Glomerular Basement Membrane Disease/diagnosis , Anti-Glomerular Basement Membrane Disease/drug therapy , Antineoplastic Agents, Immunological/therapeutic use , Rituximab/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Anti-Glomerular Basement Membrane Disease/blood , Female , Follow-Up Studies , Humans , Male , Middle Aged , Plasma Exchange/methods , Remission Induction/methods , Renal Dialysis/methods , Retrospective Studies , Young Adult
3.
Bioresour Technol ; 179: 165-172, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25543541

ABSTRACT

A prediction model of gaseous emissions (CO, CO2, NOx, SO2 and HCl) from small-scale combustion of agricultural biomass fuels was developed in order to rapidly assess their potential to be burned in accordance to current environmental threshold values. The model was established based on calculation of thermodynamic equilibrium of reactive multicomponent systems using Gibbs free energy minimization. Since this method has been widely used to estimate the composition of the syngas from wood gasification, the model was first validated by comparing its prediction results with those of similar models from the literature. The model was then used to evaluate the main gas emissions from the combustion of four dedicated energy crops (short-rotation willow, reed canary grass, switchgrass and miscanthus) previously burned in a 29-kW boiler. The prediction values revealed good agreement with the experimental results. The model was particularly effective in estimating the influence of harvest season on SO2 emissions.


Subject(s)
Air Pollutants/analysis , Biofuels , Biomass , Crops, Agricultural/chemistry , Gases/analysis , Computer Simulation , Models, Theoretical , Reproducibility of Results , Rubber/chemistry , Seasons , Sulfur/analysis , Sulfur Dioxide/analysis , Thermodynamics , Wood/chemistry
4.
Appl Microbiol Biotechnol ; 99(1): 109-19, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24859519

ABSTRACT

A new process was tested in order to produce and purify biodiesel from microalgae lipids and to recover unsaponifiable (added-value) lipids. This process is a two-step biodiesel production including a saponification reaction step followed by an esterification reaction step. The process includes a recovery of the unsaponified lipids between both reaction steps. Among the conditions tested, the following conditions were found to be the best: temperature for both steps (90 °C), saponification time (30 min), esterification time (30 min), sulfuric acid/potassium hydroxide (1.21, w/w), and methanol-lipid ratio (13.3 mL/g). Under these conditions, the fatty acid methyl ester (FAME) yield and the biodiesel purity were, respectively, 32% (g FAME/g lipid) and 77% (g FAME/g biodiesel). This study also showed that the two-step biodiesel process allows a FAME mass composition rich in palmitate (27.9-29.4 wt%), palmitoleate (24.9-26.0 wt%), elaidate (14.8-15.2 wt%), and myristate (12.1-13.0 wt%).


Subject(s)
Biofuels , Lipids/isolation & purification , Microalgae/chemistry , Esterification , Fatty Acids/analysis , Temperature , Time Factors
5.
Phys Rev Lett ; 113(12): 123005, 2014 Sep 19.
Article in English | MEDLINE | ID: mdl-25279627

ABSTRACT

We investigate, theoretically, the joint relaxation of orbital and structure in postexcitation dynamics of Rydberg states of cluster BaArN (N=250). Mixed quantum-classical dynamics is used to account for the nonadiabatic transitions among more than 160 electronic states, represented via a diatomics-in-molecules Hamiltonian. The simulation illustrates the complex multistep relaxation processes and provides detailed insight in the mechanisms contributing to the final-time experimental photoelectron spectrum.


Subject(s)
Argon/chemistry , Barium Compounds/chemistry , Models, Theoretical , Photochemical Processes , Quantum Theory , Thermodynamics
6.
Bioresour Technol ; 102(17): 7657-65, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21715161

ABSTRACT

Interactions of toluene and p-xylene in air treatment biofilters packed with an inert filter media were studied. The effect of the inlet load of toluene, p-xylene and mixtures of both compounds on the biodegradation rate was analyzed in three lab-scale biofilters. A maximum elimination capacity (EC) of 26.5 and 40.3 gCm(-3)h(-1) for an inlet load (IL) of 65.6 and 57.8 gCm(-3)h(-1) was obtained for p-xylene and toluene biofilters, respectively. Inhibition of p-xylene biodegradation by the presence of toluene took place when the mixture was treated, whereas the presence of p-xylene had an enhancing effect on the toluene removal efficiency. Specific growth rates (µ) from 0.019 to 0.068 h(-1) were calculated in the mixed biofilter, where the highest values were similar to mixtures with lower p-xylene levels (IL(p-Xyl) 8.84 ± 0.29 gCm(-3)h(-1)). Michaelis-Menten and Haldane type models were fitted to experimental EC for p-xylene and toluene biofilters, respectively.


Subject(s)
Filtration/methods , Toluene/isolation & purification , Xylenes/isolation & purification , Biodegradation, Environmental , Biomass
8.
J Chem Phys ; 121(20): 9898-905, 2004 Nov 22.
Article in English | MEDLINE | ID: mdl-15549863

ABSTRACT

The electronic structure and excited states of the Na(3)F cluster are investigated using different approximate, but numerically efficient, computational schemes, such as a 2e hybrid quantum/classical pseudopotential model with full-configuration interaction or time-dependent density-functional theory. Various quantities such as geometries and transition energies are compared with results previously obtained by multireference configuration interaction calculations, taken as reference data. The potential energy surfaces of the lowest excited states are investigated and the finite-temperature absorption spectra are calculated. The good agreement with recent beam experiments [J.-M. L'Hermite, V. Blanchet, A. Le Padellec, B. Lamory, and P. Labastie, Eur. Phys. J. D 28, 361 (2004)] leads to the conclusion that the absorption spectrum observed experimentally corresponds to the lowest energy isomer which has a C(2v) planar rhombic geometry.

9.
J Chem Phys ; 121(20): 9906-16, 2004 Nov 22.
Article in English | MEDLINE | ID: mdl-15549864

ABSTRACT

Short-time, excited-state dynamics of the lowest isomer of the Na(3)F cluster is studied theoretically in order to interpret the features of recent time-resolved pump-probe ionization experiments [J. M. L'Hermite, V. Blanchet, A. Le Padellec, B. Lamory, and P. Labastie, Eur. Phys. J. D 28, 361 (2004)]. In the present paper, we propose an identification of the vibrational motion responsible for the oscillations in the ion signal, on the basis of quantum mechanical wave packet propagations and classical trajectory calculations. The good agreement between experiment and theory allows for a clear interpretation of the detected dynamics.

10.
Ther Umsch ; 60(4): 211-7, 2003 Apr.
Article in German | MEDLINE | ID: mdl-12731431

ABSTRACT

Interventional procedures in bronchoscopy such as tissue ablation by laser, bronchusdilatation, stenting, endobronchial radiotherapy have a firm established position as treatment modalities for severe tracheobronchial obstruction. They allow quick and effective treatment of sometimes life threatening tracheal and bronchial obstructions. This article focuses on stents in the airways. A brief description of historic development is given. Currently available and frequently used stents are shown. There advantages and disadvantages are discussed. Indications for Stent-insertion in particular and for interventional endoscopy are summarized and the different techniques for insertion outlined. Based on the published literature results and complication rates are discussed.


Subject(s)
Airway Obstruction/therapy , Bronchi , Bronchial Diseases/therapy , Stents , Trachea , Tracheal Diseases/therapy , Airway Obstruction/etiology , Bronchoscopy , Carcinoma, Bronchogenic/complications , Constriction, Pathologic/etiology , Constriction, Pathologic/therapy , Contraindications , Female , Humans , Lung Neoplasms/complications , Male , Stents/adverse effects , Tracheal Stenosis/therapy
11.
Appl Microbiol Biotechnol ; 61(4): 366-73, 2003 May.
Article in English | MEDLINE | ID: mdl-12743767

ABSTRACT

The microbial communities established in three laboratory-scale compost matrix biofilters fed with toluene were characterized. The biofilters were operated for 7 weeks at inlet concentrations of toluene ranging over 250-500 ppm with daily irrigation, using a nutrient solution containing variable concentrations of nitrogen, supplied as urea, and other inorganic salts. The indigenous microflora of the compost included toluene-degrading species, making inoculation unnecessary. The numerically predominant toluene-degrading strains were isolated from the most diluted positive wells of most-probable-number counts on mineral medium with toluene as sole carbon source and identified by rRNA 16S gene sequencing. On the basis of sequence similarity, all the isolated strains were assigned to the species Pseudomonas putida, although some variations were observed in their respective sequences. It is concluded that the mode of biofilter operation including a daily supply of non-carbon nutrients created an environment favoring the constant numerical predominance of this fast-growing toluene-degrading species.


Subject(s)
Air Pollutants/metabolism , Bioreactors , Filtration , Pseudomonas putida/classification , Pseudomonas putida/metabolism , Toluene/metabolism , Biodegradation, Environmental , Carbon Dioxide/metabolism , Colony Count, Microbial , Filtration/instrumentation , Genes, rRNA , Nitrogen/metabolism , Pseudomonas putida/growth & development , Pseudomonas putida/isolation & purification , RNA, Ribosomal, 16S/genetics
12.
J Environ Qual ; 31(5): 1484-90, 2002.
Article in English | MEDLINE | ID: mdl-12371165

ABSTRACT

We studied the environmental impact (gaseous emissions) of using scrap tires as a fuel substitute at a cement plant that produces one million tons of cement per year. Using a combination of tires and coal as opposed to only coal caused variations in the pollutant emission rate. The study recorded a 37% increase in the rate of emission for CO, a 24% increase for SO2, an 11% decrease for NOx, and a 48% increase for HCl when tires were included. The rate of emission for metals increased 61% for Fe, 33% for Al, 487% for Zn, 127% for Pb, 339% for Cr, 100% for Mn, and 74% for Cu, and decreased 22% for Hg. On the other hand, the emission rate of organic compounds dropped by 14% for polycyclic aromatic hydrocarbons, 8% in naphthalene, 37% in chlorobenzene, and 45% in dioxins and furans. We used a Gaussian model of atmospheric dispersion to calculate the average pollutant concentration (1-h, 24-h, and annual concentrations) in the ambient air at ground level with the help of the ISC-ST2 software program developed by the USEPA. When tires were used, we observed (i) a 12 to 24% increase in particulate matter, this range considering the concentration variation depending on the average used (1-h, 24-h, and annual basis), 31 to 52% in CO, 22 to 34% in SO2, 39 to 52% in HCl, 12 to 27% in Fe, -3 to 8% in Al, 30 to 37% in Zn, and 270 to 885% in Pb; (ii) a decrease of 8 to 13% in NOx, 9 to 13% in polycyclic aromatic hydrocarbons, 6 to 7% in naphthalene, 32 to 39% in chlorobenzene, and 32 to 45% in dioxins and furans. The results obtained showed that the maximum ground-level concentrations were well within the environmental standards (for operation with only coal as well as for operation with a combination of coal and tires).


Subject(s)
Air Pollutants/analysis , Conservation of Natural Resources , Manufactured Materials , Refuse Disposal , Coal , Gases , Incineration , Polycyclic Aromatic Hydrocarbons/analysis , Rubber
13.
J Pharmacol Exp Ther ; 302(3): 940-8, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12183650

ABSTRACT

Ro 63-1908, 1-[2-(4-hydroxy-phenoxy)-ethyl]-4-(4-methyl-benzyl)-piperidin-4-ol, is a novel subtype-selective N-methyl-D-aspartate (NMDA) antagonist that has been characterized in vitro and in vivo. Ro 63-1908 inhibited [(3)H]dizocilpine ((3)H-MK-801) binding in a biphasic manner with IC(50) values of 0.002 and 97 microM for the high- and low-affinity sites, respectively. Ro 63-1908 selectively blocked recombinant receptors expressed in Xenopus oocytes containing NR1C + NR2B subunits with an IC(50) of 0.003 microM and those containing NR1C + NR2A subunits with an IC(50) of >100 microM, thus demonstrating greater than 20,000-fold selectivity for the recombinant receptors expressing NR1C + NR2B. Ro 63-1908 blocked these NMDA NR2B-subtype receptors in an activity-dependent manner. Ro 63-1908 was neuroprotective against glutamate-induced toxicity and against oxygen/glucose deprivation-induced toxicity in vitro with IC(50) values of 0.68 and 0.06 microM, respectively. Thus, the in vitro pharmacological characterization demonstrated that Ro 63-1908 was a potent and highly selective antagonist of the NR2B subtype of NMDA receptors. Ro 63-1908 was active against sound-induced seizures (ED(50) = 4.5 mg/kg i.p. when administered 30 min beforehand) in DBA/2 mice. The dose required to give a full anticonvulsant effect did not produce a deficit in the Rotarod test. NMDA-induced seizures were also inhibited by Ro 63-1908 with an ED(50) of 2.31 mg/kg i.v. when administered 15 min before testing. Ro 63-1908 gave a dose-related neuroprotective effect against cortical damage in a model of permanent focal ischemia. Maximum protection of 39% was seen at a plasma concentration of 450 ng/ml. There were, however, no adverse cardiovascular or CNS side-effects seen at this dosing level.


Subject(s)
Excitatory Amino Acid Antagonists/pharmacology , Phenols/pharmacology , Piperidines/pharmacology , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Acoustic Stimulation , Algorithms , Animals , Anticonvulsants/pharmacology , Brain/drug effects , Brain/metabolism , Brain/ultrastructure , Cerebral Cortex/cytology , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Electrophysiology , Excitatory Amino Acid Antagonists/metabolism , In Vitro Techniques , Infarction, Middle Cerebral Artery/drug therapy , Infarction, Middle Cerebral Artery/pathology , Macaca fascicularis , Male , Mice , Motor Activity/drug effects , Neurons/drug effects , Neurons/metabolism , Neuroprotective Agents/pharmacology , Oocytes/drug effects , Oocytes/metabolism , Phenols/metabolism , Phenols/pharmacokinetics , Piperidines/metabolism , Piperidines/pharmacokinetics , Psychomotor Performance/drug effects , Rats , Receptors, N-Methyl-D-Aspartate/metabolism , Seizures/prevention & control , Vacuoles/drug effects , Xenopus
14.
Environ Technol ; 22(8): 927-40, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11561950

ABSTRACT

In industrial activities, operation of air biofilters may be interrupted for a long period of time. In order to examine the effect of shut-down on the performance of biofilters, a pilot scale biofiltration unit was restarted up after a non-use duration of eight months. After a reacclimation period of eight days, the biofilter reached an elimination capacity of 35 g x m(-3) x h(-1) compared to 38 g x m(-3) x h(-1) before shut-down, for the same operating conditions. The results obtained indicate that the microorganism activity was completely restored and this was confirmed by the microbial count tests performed on filter bed material samples. The impact of varying the inlet concentration of toluene on biofilter performance was also investigated. A maximum elimination capacity of 120 g x m(-3) x h(-1) was achieved, compared to 135 g x m(-3) x h(-1) before shut-down. The biofilter removal efficiency exceeded 96% for inlet concentrations up to 1.8 g x m(-3). Temperature measurements revealed that the filter bed temperature depends strongly on the intensity of microbial activity and the biofilter effectiveness in eliminating toluene. Experimental data were compared with the calculations of a mathematical model. Comparison showed that the theoretical model was successful in predicting the performance of the biofiltration unit.


Subject(s)
Air Pollution/prevention & control , Solvents/chemistry , Toluene/chemistry , Bacteria , Filtration , Models, Theoretical , Temperature , Volatilization
16.
Medicina (B Aires) ; 61(3): 308-14, 2001.
Article in Spanish | MEDLINE | ID: mdl-11474879

ABSTRACT

UNLABELLED: The prevalence of children's obesity is increasing all over the world. It has been related to an increment of all morbimortality causes in the mature age. To determine the prevalence of obesity and other cardiovascular risk factors in adolescence, and correlate them with each other, we designed a cross-sectional study. A survey was applied to 2115 secondary school students, 1212 (57.3%) females and 903 (42.7%) males; blood pressure (BP) and cholesterol level were measured. Mean age: 14.8 +/- 1.6.: Body Mass Index (BMI): 20.6 +/- 3.1, 1838 (86.9%) normal, 230 (10.9%) where overweight and 47 (2.2%) obese, higher in males (OR = 1.46; IC = 1.12-1.91; p = 0.03). Weekly physical activity: 3.9 +/- 2.9 hs. higher in males (p < 0.001). Sedentarism daily hours: 3.2 +/- 1.9. ANTECEDENTS: maternal obesity 282 (13.3%), paternal 311 (14.7%) and in both 116 (6.6%). Regular consumption of fatty foods: 1711 (80.9%). SBP: 107.8 +/- 13.6; DBP: 66.9 +/- 11.5; MBP: 80.5 +/- 10.1. We found hypertension in 64 (3%) prevalent in males (p = 0.002). Cholesterol: 161.9 +/- 29.2; desirable 1283 (60.7%); normal high 628 (29.5%) and high 208 (9.8%). BMI and MBP correlation was: r = 0.25; r2 = 0.06; CI 95%: 0.02-0.11; b coefficient 0.83. We found a positive correlation of BMI with MBP (0.83 mm Hg increment for each point of BMI increment). We found significant association between parental obesity and alcohol consumption and BMI increment. We did not find any association with dietary habits, physical activity or sedentarism.


Subject(s)
Body Mass Index , Cardiovascular Diseases/epidemiology , Obesity/epidemiology , Adolescent , Age Distribution , Argentina/epidemiology , Blood Pressure , Cardiovascular Diseases/etiology , Child , Cohort Studies , Exercise , Female , Humans , Life Style , Male , Obesity/complications , Obesity/genetics , Prevalence , Risk Factors , Sex Distribution
17.
J Neurosci ; 21(11): 4104-10, 2001 Jun 01.
Article in English | MEDLINE | ID: mdl-11356898

ABSTRACT

In female rats, genitosensory stimulation received during mating initiates twice-daily prolactin (PRL) surges, a neuroendocrine response that is the hallmark of early pregnancy or pseudopregnancy (P/PSP). Nocturnal and diurnal PRL surges are expressed repeatedly for up to 2 weeks after copulation, suggesting that a neuroendocrine memory for vaginocervical stimulation (VCS) is established at the time of mating. These studies investigated whether the processing and retention of VCS involves acute glutamatergic activation or de novo protein synthesis within the medial nucleus of the amygdala (MEA), a VCS-responsive brain site that is implicated in P/PSP initiation. Pharmacological activation of the MEA with the glutamate agonist, NMDA, initiated nocturnal PRL surges, causing a PSP state in females that had not received VCS. P/PSP initiation by mating was prevented by intra-amygdalar infusion of the NMDA receptor antagonist, 2-amino-5-phosphonopentanoic acid (AP-5), provided that it was administered before mating. AP-5 treatment also disrupted mating-induced c-fos expression in the principle bed nucleus of the stria terminalis and the ventrolateral division of the ventromedial hypothalamic nucleus, but not in the medial or anteroventral periventricular preoptic nuclei. Neither P/PSP nor downstream cellular activation was prevented when a protein synthesis inhibitor, anisomycin, was administered to the MEA. The results indicate that MEA cells are critical to the early processing of VCS through NMDA channel activation, rapidly conveying information to downstream hypothalamic cell groups that modulate neuroendocrine function.


Subject(s)
Amygdala/metabolism , Memory/physiology , N-Methylaspartate/metabolism , Neurosecretory Systems/metabolism , Pseudopregnancy/metabolism , Amygdala/drug effects , Animals , Cervix Uteri/innervation , Cervix Uteri/physiology , Drug Implants , Excitatory Amino Acid Agonists/administration & dosage , Excitatory Amino Acid Antagonists/administration & dosage , Female , Memory/drug effects , Microinjections , N-Methylaspartate/administration & dosage , Neurosecretory Systems/drug effects , Preoptic Area/drug effects , Preoptic Area/metabolism , Prolactin/blood , Protein Synthesis Inhibitors/administration & dosage , Proto-Oncogene Proteins c-fos/biosynthesis , Pseudopregnancy/chemically induced , Rats , Rats, Long-Evans , Receptors, Glutamate/metabolism , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Septal Nuclei/drug effects , Septal Nuclei/metabolism , Vagina/innervation , Vagina/physiology , Ventromedial Hypothalamic Nucleus/drug effects , Ventromedial Hypothalamic Nucleus/metabolism
18.
J Cell Sci ; 114(Pt 24): 4521-32, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11792817

ABSTRACT

Microtubules polymerise from nucleation templates containing gamma tubulin. These templates are generally concentrated in discrete structures called microtubule organising centres (MTOCs). In Schizosaccharomyces pombe, an equatorial MTOC (EMTOC) forms mid-way through anaphase B and then disassembles during the final stages of cell separation. We show that the EMTOC was generated by recruiting gamma tubulin to the equatorial F-actin ring before it constricted to cleave the cell in two during cytokinesis. The EMTOC was not a continuous ring. It had a variable structure ranging from a horseshoe to a number of short bars. EMTOC integrity depended upon the integrity of the F-actin but not the microtubule cytoskeleton. EMTOC assembly required the activity of both the septation-inducing network (SIN) that regulates the onset of cytokinesis and the anaphase-promoting complex. Activation of the SIN in interphase cells induced F-actin ring formation and contraction and the synthesis of the primary septum but did not promote EMTOC assembly. In contrast, overproduction of the polo-like kinase, Plo1, which also induced multiple rounds of septation in interphase cells, induced EMTOC formation. Thus, the network governing EMTOC formation shared many of the regulatory elements that control cytokinesis but was more complex and revealed an additional function for Plo1 during mitotic exit.


Subject(s)
Drosophila Proteins , Microtubule-Organizing Center/metabolism , Mitosis/physiology , Schizosaccharomyces/cytology , Schizosaccharomyces/metabolism , Ubiquitin-Protein Ligase Complexes , Actins/metabolism , Anaphase/physiology , Anaphase-Promoting Complex-Cyclosome , Cell Cycle/physiology , Immune Sera/metabolism , Ligases/physiology , Microscopy, Confocal , Microtubule-Organizing Center/physiology , Microtubules/metabolism , Microtubules/physiology , Protein Serine-Threonine Kinases/biosynthesis , Schizosaccharomyces/enzymology , Spindle Apparatus/metabolism , Tubulin/immunology
19.
J Exp Biol ; 203(Pt 15): 2357-64, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10887074

ABSTRACT

Urea excretion by the gulf toadfish (Opsanus beta) has been shown in previous studies to be a highly pulsatile facilitated transport, with excretion probably occurring at the gill. The present study reports the isolation of an 1800 base pair (kb) cDNA from toadfish gill with one open reading frame putatively encoding a 475-residue protein, the toadfish urea transporter (tUT). tUT, the first teleostean urea transporter cloned, has high homology with UTs (facilitated urea transporters) cloned from mammals, an amphibian and a shark, and most closely resembles the UT-A subfamily. When expressed in Xenopus laevis oocytes, tUT increased urea permeability (as measured by [(14)C]urea uptake) five- to sevenfold, and this permeability increase was abolished by phloretin, a common inhibitor of other UTs. Northern analysis using the 1.8 kb clone was performed to determine the tissue distribution and dynamics of tUT mRNA expression. Of six tissues examined (gill, liver, red blood cells, kidney, skin and intestine), only gill showed expression of tUT mRNA, with a predominant band at 1.8 kb and a minor band at 3.5 kb. During several points in the urea pulse cycle of toadfish (0, 4, 6, 12 and 18 h post-pulse), measured by excretion of [(14)C]urea into the water, gill mRNA samples were obtained. Expression of tUT mRNA was found to be largely invariant relative to expression of beta-actin mRNA over the pulse cycle. These results further confirm the gill localization of urea transport in the toadfish and suggest that tUT regulation (and the regulation of pulsatile urea excretion) is probably not at the level of mRNA control. The results are discussed in the context of the mechanisms of vasopressin-regulated UT-A in mammalian kidney and morphological data for the toadfish gill.


Subject(s)
Carrier Proteins/genetics , Fishes/genetics , Fishes/metabolism , Membrane Glycoproteins/genetics , Membrane Transport Proteins , Urea/metabolism , Amino Acid Sequence , Animals , Base Sequence , DNA Primers/genetics , DNA, Complementary/genetics , Female , Gene Expression , Gills/metabolism , In Vitro Techniques , Molecular Sequence Data , Oocytes/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Homology, Amino Acid , Tissue Distribution , Xenopus laevis , Urea Transporters
20.
J Biol Chem ; 275(38): 29521-7, 2000 Sep 22.
Article in English | MEDLINE | ID: mdl-10889201

ABSTRACT

To identify the structural features required for regulation of the mitochondrial permeability transition pore (PTP) by ubiquinone analogs (Fontaine, E., Ichas, F., and Bernardi, P. (1998) J. Biol. Chem. 40, 25734-25740), we have carried out an analysis with quinone structural variants. We show that three functional classes can be defined: (i) PTP inhibitors (ubiquinone 0, decylubiquinone, ubiquinone 10, 2,3-dimethyl-6-decyl-1,4-benzoquinone, and 2,3,5-trimethyl-6-geranyl-1,4-benzoquinone); (ii) PTP inducers (2,3-dimethoxy-5-methyl-6-(10-hydroxydecyl)-1,4-benzoquinone and 2,5-dihydroxy-6-undecyl-1,4-benzoquinone); and (iii) PTP-inactive quinones that counteract the effects of both inhibitors and inducers (ubiquinone 5 and 2,3,5-trimethyl-6-(3-hydroxyisoamyl)-1,4-benzoquinone) . The structure-function correlation indicates that minor modifications in the isoprenoid side chain can turn an inhibitor into an activator, and that the methoxy groups are not essential for the effects of quinones on the PTP. Since the ubiquinone analogs used in this study have a similar midpoint potential and decrease mitochondrial production of reactive oxygen species to the same extent, these results support the hypothesis that quinones modulate the PTP through a common binding site rather than through oxidation-reduction reactions. Occupancy of this site can modulate the PTP open-closed transitions, possibly through secondary changes of the PTP Ca(2+) binding affinity.


Subject(s)
Ion Channels , Membrane Proteins/physiology , Mitochondria, Liver/physiology , Ubiquinone , Animals , Calcium/physiology , Cell Membrane Permeability/drug effects , Dose-Response Relationship, Drug , Electron Transport/drug effects , Electron Transport/physiology , Membrane Proteins/drug effects , Mitochondrial Membrane Transport Proteins , Mitochondrial Permeability Transition Pore , Rats , Ubiquinone/analogs & derivatives , Ubiquinone/pharmacology , Ubiquinone/physiology
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