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1.
Phys Rev Lett ; 129(2): 021801, 2022 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-35867467

RESUMO

We report the first results of a search for leptophobic dark matter (DM) from the Coherent-CAPTAIN-Mills (CCM) liquid argon (LAr) detector. An engineering run with 120 photomultiplier tubes (PMTs) and 17.9×10^{20} protons on target (POT) was performed in fall 2019 to study the characteristics of the CCM detector. The operation of this 10-ton detector was strictly light based with a threshold of 50 keV and used coherent elastic scattering off argon nuclei to detect DM. Despite only 1.5 months of accumulated luminosity, contaminated LAr, and nonoptimized shielding, CCM's first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter models with a baryonic vector portal. With an expected background of 115 005 events, we observe 115 005+16.5 events which is compatible with background expectations. For a benchmark mediator-to-DM mass ratio of m_{V_{B}}/m_{χ}=2.1, DM masses within the range 9 MeV≲m_{χ}≲50 MeV are excluded at 90% C. L. in the leptophobic model after applying the Feldman-Cousins test statistic. CCM's upgraded run with 200 PMTs, filtered LAr, improved shielding, and 10 times more POT will be able to exclude the remaining thermal relic density parameter space of this model, as well as probe new parameter space of other leptophobic DM models.

2.
Rev Sci Instrum ; 89(10): 10K109, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30399843

RESUMO

Material clusters of different sizes are known to exist in high-temperature plasmas due to plasma-wall interactions. The facts that these clusters, ranging from sub-microns to above mm in size, can move from one location to another quickly and that there are a lot of them make high-speed imaging and tracking one of the best, effective, and sometimes only diagnostic. An unsupervised machine learning technique based on deconvolutional neural networks is developed to analyze two-camera videos of high-temperature microparticles generated from exploding wires. The neural network utilizes a locally competitive algorithm to infer representations and optimize a dictionary composed of kernels, or basis vectors, for image analysis. Our primary goal is to use this method for feature recognition and prediction of the time-dependent three-dimensional (or "4D") microparticle motion. Features equivalent to local velocity vectors have been identified as the dictionary kernels or "building blocks" of the scene. The dictionary elements from the left and right camera views are found to be strongly correlated and satisfy the projection geometrical constraints. The results show that unsupervised machine learning techniques are promising approaches to process large sets of images for high-temperature plasmas and other scientific experiments. Machine learning techniques can be useful to handle the large amount of data and therefore aid the understanding of plasma-wall interaction.

3.
Biosystems ; 149: 139-153, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27484338

RESUMO

Boolean networks (and more general logic models) are useful frameworks to study signal transduction across multiple pathways. Logic models can be learned from a prior knowledge network structure and multiplex phosphoproteomics data. However, most efficient and scalable training methods focus on the comparison of two time-points and assume that the system has reached an early steady state. In this paper, we generalize such a learning procedure to take into account the time series traces of phosphoproteomics data in order to discriminate Boolean networks according to their transient dynamics. To that end, we identify a necessary condition that must be satisfied by the dynamics of a Boolean network to be consistent with a discretized time series trace. Based on this condition, we use Answer Set Programming to compute an over-approximation of the set of Boolean networks which fit best with experimental data and provide the corresponding encodings. Combined with model-checking approaches, we end up with a global learning algorithm. Our approach is able to learn logic models with a true positive rate higher than 78% in two case studies of mammalian signaling networks; for a larger case study, our method provides optimal answers after 7min of computation. We quantified the gain in our method predictions precision compared to learning approaches based on static data. Finally, as an application, our method proposes erroneous time-points in the time series data with respect to the optimal learned logic models.


Assuntos
Redes Reguladoras de Genes , Análise de Séries Temporais Interrompida/métodos , Lógica , Animais , Redes Reguladoras de Genes/fisiologia , Humanos , Transdução de Sinais/fisiologia
4.
Dalton Trans ; 45(16): 6856-65, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-26880661

RESUMO

The ruthenium-triphos and diphosphine-catalysed amination of alcohols with ammonia is reported. Various types of triphos derivatives with electron-donating functional group were synthesized and used as ligands in the Ru-catalysed alcohol amination with NH3. The triphos derivatives are effective for the formation of primary amines. On the other hand, if hemilabile diphosphines as tridentate ligands are used, mixtures of secondary-along with primary amines are obtained. It was found that even simple diphosphines can be used as ligands for the selective formation of the secondary amines. The diphosphine system allows a new entry to the Ru-catalysed formation of secondary amines.

5.
Bioinformatics ; 20(10): 1491-4, 2004 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-15231540

RESUMO

MOTIVATION: Continued development of analytical techniques based on gas chromatography and mass spectrometry now facilitates the generation of larger sets of metabolite concentration data. An important step towards the understanding of metabolite dynamics is the recognition of stable states where metabolite concentrations exhibit a simple behaviour. Such states can be characterized through the identification of significant thresholds in the concentrations. But general techniques for finding discretization thresholds in continuous data prove to be practically insufficient for detecting states due to the weak conditional dependences in concentration data. RESULTS: We introduce a method of recognizing states in the framework of decision tree induction. It is based upon a global analysis of decision forests where stability and quality are evaluated. It leads to the detection of thresholds that are both comprehensible and robust. Applied to metabolite concentration data, this method has led to the discovery of hidden states in the corresponding variables. Some of these reflect known properties of the biological experiments, and others point to putative new states. AVAILABILITY: An implementation of this approach can be obtained from the authors upon request.


Assuntos
Algoritmos , Limiar Diferencial/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Modelos Biológicos , Proteínas de Plantas/metabolismo , Transdução de Sinais/fisiologia , Solanum tuberosum/metabolismo , Simulação por Computador , Metabolismo Energético/fisiologia , Perfilação da Expressão Gênica/métodos , Homeostase/fisiologia
6.
Semin Dial ; 15(6): 407-13, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12437535

RESUMO

Automated peritoneal dialysis (APD) has become the fastest growing dialysis modality in Europe and the United States in recent years. Freedom from daytime exchanges, flexibility of prescription, performance in recumbent position leading to enhanced treatment efficacy, and a decreased incidence of peritonitis are the main advantages of APD over CAPD. Studies on new developments of glucose-based PD fluids were performed predominantly in CAPD patients. High volumes and frequent APD cycles in patients may aggravate the adverse effects of standard CAPD fluids on the peritoneal membrane with increasing time on PD. New, glucose-based PD fluids with neutral pH, very low concentrations of glucose degradation products (GDPs), containing either lactate or bicarbonate as buffering substances have been introduced into clinical use recently. With these new fluids, various in vitro, ex vivo, and in vivo studies could demonstrate a better preservation of peritoneal cell viability and growth, less inhibited secretory cell functions, a significant reduction in the formation of advanced glycation end products (AGEs), and clinical signs for an improved preservation of peritoneal mesothelial cells indicated by an increase in effluent CA125. One has to be aware, however, that uremia per se prior to initiation of PD, as well as during PD treatment itself, directly impacts on peritoneal membrane structural changes so that new, more biocompatible PD fluids may not be completely sufficient to prevent morphologic and functional changes of the membrane. Due to a strong sodium sieving during APD, PD fluids with sodium concentrations of 125-130 mmol/L may be beneficial. Systematic calcium kinetic studies have not yet been performed in APD patients. APD fluids should offer a calcium concentration range of 1.0-1.75 mmol/L in order to enable an individualized APD prescription. For long-term APD treatment, better knowledge of peritoneal membrane physiology and PD kinetics should promote individualization of prescriptions. New, pH-neutral PD solutions with minimized amounts of GDPs may be a significant step forward to improved membrane preservation during long-term APD treatment.


Assuntos
Soluções para Diálise , Diálise Peritoneal , Acidose/metabolismo , Automação , Cálcio , Soluções para Diálise/química , Glucose , Humanos , Concentração de Íons de Hidrogênio , Diálise Peritoneal/métodos , Peritônio , Sódio
7.
Biochem Biophys Res Commun ; 280(5): 1408-14, 2001 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-11162688

RESUMO

Conventional peritoneal dialysis fluids (PDFs) lead to formation of advanced glycation end-products (AGE) in the peritoneal membrane. In this study, we investigated in vitro the dependence of AGE formation on regular changes of PDFs, as performed during continuous ambulatory peritoneal dialysis (CAPD), and on the contribution of high glucose concentration versus glucose degradation products (GDPs). Under conditions similar to CAPD, protein glycating activity of a conventional single chamber bag PDF (CAPD 4.25%), two double chamber bag PDFs (CAPD Balance 4.25% and CAPD Bicarbonate 4.25%) and a sterile filtered control was measured in vitro by N(epsilon)-(carboxymethyl)lysine (CML) and imidazolones, two well characterized, physiologically relevant AGE structures. Regular changes of PDFs increased AGE formation (CML 3.3-fold and imidazolone 2.6-fold) compared to incubation without changes. AGE formation by CAPD 4.25% was increased compared to control (imidazolones 7.9-fold and CML 3.3-fold) and the use of double chamber bag PDFs led to a decrease of imidazolones by 79% (CAPD Bicarbonate 4.25%) and by 66% (CAPD Balance 4.25%) and to CML contents similar to the control. These results indicate that a major part of AGEs were formed by GDPs in PDFs, whereas only a minor part was due to high glucose concentration. The use of double chamber bag fluids can reduce AGE formation considerably.


Assuntos
Imidazóis/química , Lisina/análogos & derivados , Lisina/química , Diálise Peritoneal Ambulatorial Contínua/instrumentação , Soluções para Diálise/química , Fluorescência , Produtos Finais de Glicação Avançada/química , Humanos , Albumina Sérica/química , Fatores de Tempo
8.
Perit Dial Int ; 21 Suppl 3: S108-13, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11887803

RESUMO

OBJECTIVE: Glucose degradation products (GDPs) and low pH are potential causes of bioincompatibility of peritoneal dialysis fluids (PDFs). The aim of the present study was to compare the effect of 6 weeks' exposure of the peritoneum in rats to two different PDFs: a standard PDF with a low pH and high level of GDPs (CAPD 3: Fresenius Medical Care, Bad Homburg, Germany), and a modified PDF with a low level of GDPs and a physiologic pH (CAPD 3 Balance: Fresenius Medical Care). METHODS: After catheter implantation, rats were exposed twice daily for 6 weeks to CAPD 3 fluid or to CAPD 3 Balance. At the beginning and at the end of the study, a 4-hour dwell was performed in every rat to evaluate intraperitoneal inflammation and its effect on total collagen synthesis in the in vitro cultured rat mesothelial cells (ex vivo study). Additionally, after 6 weeks' exposure, the peritoneal cavity was opened, and macroscopic changes were evaluated according to a semiquantitative scale. Peritoneal samples were also taken for morphology study. RESULTS: In rats treated with CAPD 3 fluid, intraperitoneal inflammation was comparable at the beginning and at the end of the experiment. In animals exposed to CAPD 3 Balance, the intensity of the intraperitoneal inflammation decreased during the study (cell count, p = 0.0781; neutrophil:macrophage ratio, p < 0.01; nitrite concentration, p < 0.05; hyaluronan level, p < 0.05). The capacity of effluent dialysate from CAPD 3 rats to activate collagen synthesis in in vitro-cultured mesothelial cells was the same at the beginning and at the end of the study. In the CAPD 3 Balance group, this capacity was statistically significantly lower at the end of the study than at the beginning (p < 0.05). The mean thickness of the visceral peritoneum was comparable in both groups of animals, but, macroscopically, more severe fibrosis was found in the peritoneum of rats exposed to CAPD 3 as compared with animals treated with CAPD 3 Balance (p < 0.05). CONCLUSION: We showed that, in the rat model of peritoneal dialysis, chronic exposure of the peritoneum to PDFs with low GDPs and a physiologic pH diminished the intraperitoneal inflammatory reaction induced by dialysis, and reduced peritoneal fibrosis.


Assuntos
Soluções para Diálise/toxicidade , Diálise Peritoneal Ambulatorial Contínua , Peritônio/efeitos dos fármacos , Animais , Células Cultivadas , Colágeno/biossíntese , Soluções para Diálise/química , Epitélio/metabolismo , Glucose/análise , Glucose/metabolismo , Glucose/toxicidade , Concentração de Íons de Hidrogênio , Masculino , Peritônio/metabolismo , Peritônio/patologia , Peritonite/metabolismo , Ratos , Ratos Wistar
9.
Perit Dial Int ; 21 Suppl 3: S35-40, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11887852

RESUMO

OBJECTIVE: Increased peritoneal vasculature has been reported in long-term peritoneal dialysis (PD), and vascular endothelial growth factors (VEGFs) have been found in dialysate. High concentrations of glucose or lactate, glucose degradation products (GDPs), and low pH of dialysis solutions are all possible factors in increased peritoneal VEGF synthesis. In this study, we investigated the effects of high glucose dialysis solutions on VEGF synthesis by peritoneal vascular endothelial cells (PVECs). METHODS: The PVECs were isolated from rat omentum and were incubated for 4 hours in three different culture media [M199 media (control), conventional dialysis solutions containing 4.25% glucose diluted with an equal volume of M199 media (HGD), and M199 media containing 118 mmol/L mannitol as an osmolar control (mannitol)]. Levels of VEGF protein in the culture supernatant were measured by ELISA, and mRNA expression was determined by Northern blot analysis. Data are presented as percent of control. RESULTS: After incubation for 4 hours, the number of cells did not differ between the 3 groups. Levels of VEGF in culture supernatant were significantly higher in the HGD group (124% +/- 19%, p = 0.006) as compared with the control and mannitol (85% +/- 10%) groups. The mRNA expression of VEGF appeared to be higher in the HGD group (128% +/- 49%) than in the control and mannitol (94% +/- 18%) groups. CONCLUSION: High glucose dialysis solutions increased VEGF synthesis by PVECs. The relationship between VEGF synthesis by PVECs and neovascularization of the peritoneum observed in long-term peritoneal dialysis patients has to be studied further.


Assuntos
Soluções para Diálise , Fatores de Crescimento Endotelial/biossíntese , Endotélio Vascular/metabolismo , Glucose/farmacologia , Linfocinas/biossíntese , Diálise Peritoneal , Peritônio/irrigação sanguínea , Animais , Northern Blotting , Células Cultivadas , Soluções para Diálise/química , Fatores de Crescimento Endotelial/genética , Ensaio de Imunoadsorção Enzimática , Concentração de Íons de Hidrogênio , Soluções Hipertônicas , Linfocinas/genética , Manitol/farmacologia , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Receptores de Fatores de Crescimento do Endotélio Vascular , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
10.
Mol Biol Cell ; 11(11): 3925-35, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11071917

RESUMO

FKBP65 (65-kDa FK506-binding protein) is a member of the highly conserved family of intracellular receptors called immunophilins. All have the property of peptidyl-prolyl cis-trans isomerization, and most have been implicated in folding and trafficking events. In an earlier study, we identified that FKBP65 associates with the extracellular matrix protein tropoelastin during its transport through the cell. In the present study, we have carried out a detailed investigation of the subcellular localization of FKBP65 and its relationship to tropoelastin. Using subcellular fractionation, Triton X-114 phase separation, protease protection assays, and immunofluorescence microscopy (IF), we have identified that FKBP65 is contained within the lumen of the endoplasmic reticulum (ER). Subsequent IF studies colocalized FKBP65 with tropoelastin and showed that the two proteins dissociate before reaching the Golgi apparatus. Immunohistochemical localization of FKBP65 in developing lung showed strong staining of vascular and airway smooth muscle cells. Similar areas stained positive for the presence of elastic fibers in the extracellular matrix. The expression of FKBP65 was investigated during development as tropoelastin is not expressed in adult tissues. Tissue-specific expression of FKBP65 was observed in 12-d old mouse tissues; however, the pattern of expression of FKBP65 was not restricted to those tissues expressing tropoelastin. This suggests that additional ligands for FKBP65 likely exist within the ER. Remarkably, in the adult tissues examined, FKBP65 expression was absent or barely detectable. Taken together, these results support an ER-localized FKBP65-tropoelastin interaction that occurs specifically during growth and development of tissues.


Assuntos
Retículo Endoplasmático/metabolismo , Matriz Extracelular/metabolismo , Pulmão/crescimento & desenvolvimento , Peptidilprolil Isomerase , Proteínas de Ligação a Tacrolimo/metabolismo , Sequência de Aminoácidos , Animais , Bovinos , Regulação da Expressão Gênica no Desenvolvimento , Complexo de Golgi/metabolismo , Membranas Intracelulares , Pulmão/citologia , Pulmão/metabolismo , Camundongos , Dados de Sequência Molecular , Músculo Liso/metabolismo , Proteínas de Ligação a Tacrolimo/genética , Tropoelastina/metabolismo
11.
Mol Biol Cell ; 10(11): 3595-605, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10564258

RESUMO

Elastic fibers consist of two morphologically distinct components: elastin and 10-nm fibrillin-containing microfibrils. During development, the microfibrils form bundles that appear to act as a scaffold for the deposition, orientation, and assembly of tropoelastin monomers into an insoluble elastic fiber. Although microfibrils can assemble independent of elastin, tropoelastin monomers do not assemble without the presence of microfibrils. In the present study, immortalized ciliary body pigmented epithelial (PE) cells were investigated for their potential to serve as a cell culture model for elastic fiber assembly. Northern analysis showed that the PE cells express microfibril proteins but do not express tropoelastin. Immunofluorescence staining and electron microscopy confirmed that the microfibril proteins produced by the PE cells assemble into intact microfibrils. When the PE cells were transfected with a mammalian expression vector containing a bovine tropoelastin cDNA, the cells were found to express and secrete tropoelastin. Immunofluorescence and electron microscopic examination of the transfected PE cells showed the presence of elastic fibers in the matrix. Biochemical analysis of this matrix showed the presence of cross-links that are unique to mature insoluble elastin. Together, these results indicate that the PE cells provide a unique, stable in vitro system in which to study elastic fiber assembly.


Assuntos
Corpo Ciliar/metabolismo , Proteínas Contráteis/metabolismo , Proteínas da Matriz Extracelular , Microfibrilas/metabolismo , Animais , Bovinos , Células Cultivadas , Condrócitos , Desmosina/análise , Tecido Elástico/metabolismo , Elastina/genética , Elastina/metabolismo , Matriz Extracelular/ultraestrutura , Fibrilinas , Imunofluorescência , Humanos , Técnicas In Vitro , Microfibrilas/ultraestrutura , Proteínas dos Microfilamentos/química , Microscopia Eletrônica , Fatores de Processamento de RNA , Transfecção , Tropoelastina/genética , Tropoelastina/metabolismo
12.
J Am Soc Nephrol ; 10(6): 1159-69, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10361853

RESUMO

Human kidney proximal tubule epithelia express the ATP-dependent export pump for anionic conjugates encoded by the MRP2 (cMRP/cMOAT) gene (symbol ABCC2). MRP2, the apical isoform of the multidrug resistance protein, is an integral membrane glycoprotein with a molecular mass of approximately 190 kD that was originally cloned from liver and localized to the canalicular (apical) membrane domain of hepatocytes. In this study, MRP2 was detected in human kidney cortex by reverse transcription-PCR followed by sequencing of a 826-bp cDNA fragment and by immunoblotting using two different antibodies. Human MRP2 was localized to the apical brush-border membrane domain of proximal tubules by double and triple immunofluorescence microscopy including laser scanning microscopy. The expression of MRP2 in renal cell carcinoma was studied by reverse transcription-PCR and immunoblotting in samples from patients undergoing tumor-nephrectomy without prior chemotherapy. Clear-cell carcinomas, originating from the proximal tubule epithelium, expressed MRP2 in 95% (18 of 19) of cases. Immunofluorescence microscopy of MRP2 in clear-cell carcinoma showed a lack of a distinct apical-to-basolateral tumor cell polarity and an additional localization of MRP2 on intracellular membranes. MRP2, the first cloned ATP-dependent export pump for anionic conjugates detected in human kidney, may be involved in renal excretion of various anionic endogenous substances, xenobiotics, and cytotoxic drugs. This conjugate-transporting ATPase encoded by the MRP2 gene has a similar substrate specificity as the multidrug resistance protein MRP1, and may contribute to the multidrug resistance of renal clear-cell carcinomas.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/isolamento & purificação , Carcinoma de Células Renais/genética , Genes MDR/genética , Neoplasias Renais/genética , Túbulos Renais Proximais/química , Proteínas de Membrana Transportadoras , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Carcinoma de Células Renais/química , Células Clonais , Dipeptidil Peptidase 4/análise , Expressão Gênica , Marcadores Genéticos , Humanos , Immunoblotting , Neoplasias Renais/química , Microscopia de Fluorescência , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteína 2 Associada à Farmacorresistência Múltipla , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Neoplásico/análise , Valores de Referência , Sensibilidade e Especificidade
13.
Pediatr Res ; 42(2): 241-6, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9262230

RESUMO

Hyperprostaglandin E syndrome (HPS), the prenatal variant of Bartter's syndrome, is characterized by a marked and selective stimulation of prostaglandin E (PGE2) synthesis. In the study group HPS patients showed increased urinary levels of PGE2, an index of renal, and of 11 alpha-hydroxy-9,15-dioxo-2,3,4,5,20-pentanor-19-carboxyprostano ic acid (PGE-M), an index of systemic PGE2 synthesis of 470% and of 570%, respectively. In addition, plasma concentration of PGE-M was also elevated 6.3-fold when compared with a control group. The urinary levels of other prostanoids were unaltered. During indomethacin treatment in both groups prostanoid excretion rates were suppressed to similar levels. To investigate the origin of stimulated prostanoid biosynthesis in HPS patients CD14+ monocytes were isolated from plasma samples, and the prostanoid synthesis was analyzed. The pattern and amounts of metabolites synthesized from endogenous arachidonic acid pools did not vary significantly between monocytes of the HPS and the control group. Thromboxane A2 (TXA2) was formed as the major prostanoid product. Using PGH2 as an exogenous substrate, again no difference in PGE2 biosynthesis was observed, indicating no difference in PGE-synthetic activity between both groups. Additionally, mRNA expression analysis of CD14+ monocytes via RT-PCR delineated the constitutive expression of cyclooxygenase-1, cyclooxygenase-2, and thromboxane synthase mRNA in cells from HPS patients and controls without statistical differences between these two groups. In conclusion, our data show that monocytes are not the source for the increased PGE2 biosynthesis in children with HPS, and a genetic defect in PGE synthesis can be excluded as the primary event in the pathogenesis in HPS.


Assuntos
Monócitos/metabolismo , Prostaglandinas E/sangue , Prostaglandinas/biossíntese , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , Feminino , Humanos , Lactente , Isoenzimas/genética , Receptores de Lipopolissacarídeos/sangue , Masculino , Proteínas de Membrana , Monócitos/imunologia , Reação em Cadeia da Polimerase/métodos , Prostaglandina-Endoperóxido Sintases/genética , Prostaglandinas/sangue , Prostaglandinas/urina , DNA Polimerase Dirigida por RNA , Tromboxano-A Sintase/genética
14.
J Am Soc Nephrol ; 8(8): 1213-21, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9259347

RESUMO

A novel ATP-dependent export pump for amphiphilic anionic conjugates, which has been cloned recently from liver, was identified in rat kidney and localized to the apical membrane domain of proximal tubule epithelia. This 190-kD membrane glycoprotein (Mrp2) has been described previously as the hepatocyte canalicular isoform of the multidrug resistance protein and as the canalicular multispecific organic anion transporter. Mrp2 was identified in kidney by reverse transcription PCR followed by sequencing of the amplified 786-bp fragment and by immunoblotting, using an antibody specifically reacting with the carboxy terminus of rat Mrp2. Double immunofluorescence and confocal laser-scanning microscopy showed the presence of Mrp2 in the brush-border membrane domain of segments S1, S2, and S3 of proximal tubule epithelia. Mrp2 was not detectable in other segments of the nephron. The onset of Mrp2 expression during development occurred in a very early stage of nephron development. Mrp2 represents the first cloned ATP-dependent export pump for amphiphilic organic anions identified in kidney and localized to the apical membrane domain of proximal tubule epithelia. Mrp2 may contribute to cellular detoxification and to the secretion of endogenous and xenobiotic anionic substances, most of which are conjugates, from the blood into urine.


Assuntos
Proteínas de Transporte/genética , Túbulos Renais Proximais/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Transporte de Ânions , Sequência de Bases , Primers do DNA/genética , Expressão Gênica , Immunoblotting , Canais Iônicos/genética , Masculino , Glicoproteínas de Membrana/genética , Microscopia Confocal , Microscopia de Fluorescência , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Mutantes , Ratos Sprague-Dawley
15.
Insect Mol Biol ; 6(3): 291-9, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9272447

RESUMO

We report the cloning and primary characterization of both cDNA and genomic fragments from the white gene of the yellow fever mosquito, Aedes aegypti. Comparisons of the conceptual translation product with white genes from four other species within the order Diptera show that the Ae. aegypti gene is most similar to the white gene of the mosquito vector of human malaria, Anopheles gambiae (86% identity and 92% similarity). The analysis of the primary sequence of genomic DNA at the 5'-end of the coding region revealed the presence of an intron that is also present in An. gambiae, but not in the vinegar fly, Drosophila melanogaster. The isolated clones of the Ae. aegypti white gene will enable the construction of a marker gene for use in the development of a germline transformation system for this species.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Aedes/genética , Proteínas de Drosophila , Proteínas do Olho/genética , Genes de Insetos/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Proteínas do Olho/química , Marcadores Genéticos , Íntrons/genética , Dados de Sequência Molecular , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico , Transformação Genética
16.
Z Orthop Ihre Grenzgeb ; 132(5): 371-6, 1994.
Artigo em Alemão | MEDLINE | ID: mdl-7985395

RESUMO

As a seeming law of nature the possibility of making use of various multiplanar sectional imaging techniques is accompanied by diagnostic exaggeration. Simple and cost effective procedures with low radiation dosage such as plain x-rays of the spine are being thrust into the background. Not seldom are patients referred to the spine surgeon with MRI or Cat scan at hand but lacking standard radiographs. As far as the assessment of intervertebral disc disease is concerned the combination of plain X-rays of the spine and computed tomography of the level in question turned out to be sufficient for indication of the operation in more than 90% of 450 patients after nucleotomie at the Orthopedic University Clinic Mainz. To our mind MRI should be restricted to cases in whom disc surgery had failed to relieve sciatica. Here it allows to distinguish between a recurrent HNP and postoperative scar tissue. In our patients myelography, an invasive procedure, has its role only in emergency diagnostics, and in the dynamic-functional examination.


Assuntos
Diagnóstico por Imagem , Deslocamento do Disco Intervertebral/diagnóstico , Vértebras Lombares , Feminino , Humanos , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mielografia , Tomografia Computadorizada por Raios X
17.
Z Orthop Ihre Grenzgeb ; 131(5): 446-51, 1993.
Artigo em Alemão | MEDLINE | ID: mdl-8256493

RESUMO

Total hip arthroplasty was performed with PMMA-augmented tumor prostheses in 42 individuals suffering from metastatic destruction of the proximal end of the femur at the Orthopedic University Hospital Mainz from 1980 to 1992. Neoplastic lesions had been triggered by carcinomas of the breast in 25 female patients. 24 of our patients presented with pathologic fractures. In all patients capable of walking preoperatively early mobilization could be attained by total hip arthroplasty. Pain relief was achieved in each patient. Resection of the major trochanter and, partially, of the pelvitrochanteric muscle sleeve entailed luxation of the prosthesis six times in 5 individuals during the first postoperative two months; closed reduction was practicable in all of them. Postoperative survival time amounted to an average of 10.5 months. Leg length and hip function were successfully re-established by implanting tumor prostheses after resection of the proximal part of the femur.


Assuntos
Neoplasias Femorais/secundário , Prótese de Quadril , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Neoplasias Femorais/diagnóstico por imagem , Neoplasias Femorais/cirurgia , Seguimentos , Fraturas Espontâneas/diagnóstico por imagem , Fraturas Espontâneas/cirurgia , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Falha de Prótese , Radiografia , Amplitude de Movimento Articular/fisiologia
19.
Rofo ; 158(2): 121-6, 1993 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-8443356

RESUMO

In 105 patients CT studies were done prospectively after renal ESWL with a second generation lithotripter. 33 (31%) of the patients had renal oedema (n = 8), renal (n = 20) or extrarenal (n = 31) bleeding. Three of the 23 patients who had a three year follow-up had chronic renal changes, 10 had renal stones. As blunt renal trauma can be the cause of renal hypertension a longterm follow-up is necessary in ESWL patients, particularly if there was renal bleeding after treatment. Further studies are needed to determine the exact risk of renal hypertension after ESWL.


Assuntos
Hipertensão Renal/etiologia , Cálculos Renais/terapia , Litotripsia/efeitos adversos , Tecnécio Tc 99m Mertiatida , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Hipertensão Renal/diagnóstico por imagem , Cálculos Renais/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Cintilografia
20.
Rofo ; 157(4): 338-43, 1992 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-1391835

RESUMO

Extracorporeal shock wave lithotripsy (ESWL) has become the treatment of choice for urinary calculi. 117 patients were studied prospectively with 99mTc mercaptoacetyltriglycine (MAG3) before and after ESWL. 79 (66%) of the 119 kidneys treated had abnormal findings. Of these 63/119 (53%) had abnormal scans. 41 (65%) had focal lesions with a delayed intrarenal transport. The remaining 22 had a diffuse delay of intrarenal transport. A loss of relative renal function of 3% and more compared to the pretreatment values was observed in 50/119 (42%) patients. 99mTc MAG3 should be done routinely together with radiologic tests (CT or MRI) before and after ESWL to select the patients at risk for post ESWL hypertension.


Assuntos
Nefropatias/diagnóstico por imagem , Rim/diagnóstico por imagem , Litotripsia , Tecnécio Tc 99m Mertiatida , Feminino , Câmaras gama , Humanos , Rim/fisiopatologia , Cálculos Renais/complicações , Cálculos Renais/diagnóstico por imagem , Cálculos Renais/terapia , Nefropatias/epidemiologia , Nefropatias/etiologia , Litotripsia/efeitos adversos , Litotripsia/estatística & dados numéricos , Masculino , Estudos Prospectivos , Cintilografia , Fatores de Tempo
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