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1.
Opt Express ; 29(24): 40333-40344, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34809377

RESUMO

Short-pulse metrology and dynamic studies in the extreme ultraviolet (XUV) spectral range greatly benefit from interferometric measurements. In this contribution a Michelson-type all-reflective split-and-delay autocorrelator operating in a quasi amplitude splitting mode is presented. The autocorrelator works under a grazing incidence angle in a broad spectral range (10 nm - 1 µm) providing collinear propagation of both pulse replicas and thus a constant phase difference across the beam profile. The compact instrument allows for XUV pulse autocorrelation measurements in the time domain with a single-digit attosecond precision and a useful scan length of about 1 ps enabling a decent resolution of E/ΔE = 2000 at 26.6 eV. Its performance for selected spectroscopic applications requiring moderate resolution at short wavelengths is demonstrated by characterizing a sharp electronic transition at 26.6 eV in Ar gas. The absorption of the 11th harmonic of a frequency-doubled Yb-fiber laser leads to the well-known 3s3p64p1P1 Fano resonance of Ar atoms. We benchmark our time-domain interferometry results with a high-resolution XUV grating spectrometer and find an excellent agreement. The common-path interferometer opens up new opportunities for short-wavelength femtosecond and attosecond pulse metrology and dynamic studies on extreme time scales in various research fields.

2.
Opt Lett ; 45(11): 3013-3016, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32479446

RESUMO

We demonstrate an efficient approach for enhancing the spectral broadening of long laser pulses and for efficient frequency redshifting by exploiting the intrinsic temporal properties of molecular alignment inside a gas-filled hollow-core fiber (HCF). We find that laser-induced alignment with durations comparable to the characteristic rotational time scale TRotAlign enhances the efficiency of redshifted spectral broadening compared to noble gases. The applicability of this approach to Yb lasers with (few hundred femtoseconds) long pulse duration is illustrated, for which efficient broadening based on conventional Kerr nonlinearity is challenging to achieve. Furthermore, this approach proposes a practical solution for high energy broadband long-wavelength light sources, and it is attractive for many strong field applications.

3.
Klin Padiatr ; 228(1): 11-6, 2016 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-26766668

RESUMO

BACKGROUND: Based on an increasing number of outpatient treatments, an extensive demand planning is necessary to ensure the quality of medical care. University outpatient clinics are special parts of this sector and therefore it is necessary that a research demonstrates the nearly uninvestigated position of a paediatric outpatient clinic. PATIENTS: The research at the university hospital for children and adolescents in Leipzig started in 2009 to survey 2283 of in total 9391 patients and the physicians. METHODS: Sociodemographic data as well as economic and medical facts were determined by using questionnaires. In each case a questionnaire was answered by the children or their accompanying persons and a separate one was completed by the respective doctor. RESULTS: The results created a foundation, on the basis of patient volume per day and per daytime. Less than 20% of the children admitted to consult the clinic for their first time. The majority of patients visit them because of a letter of referral. Most of the patients (58%) were younger than 6 years old. Approximately 35% of patients did not come from the city region of Leipzig. CONCLUSION: The investigation evidenced the necessity of a day and night operating institution for children in the region of Leipzig as well as the high specialisation of the outpatient clinic. In need of further investigation is the cooperation between several physicians to find out if this lots of medical examination are necessary or if there took place overlapping.


Assuntos
Hospitais Universitários/estatística & dados numéricos , Hospitais Universitários/normas , Ambulatório Hospitalar/estatística & dados numéricos , Ambulatório Hospitalar/normas , Pediatria/normas , Gestão da Qualidade Total/estatística & dados numéricos , Gestão da Qualidade Total/normas , Adolescente , Plantão Médico/normas , Plantão Médico/estatística & dados numéricos , Criança , Pré-Escolar , Comportamento do Consumidor , Alemanha , Pesquisa sobre Serviços de Saúde , Humanos , Garantia da Qualidade dos Cuidados de Saúde/normas , Garantia da Qualidade dos Cuidados de Saúde/estatística & dados numéricos , Encaminhamento e Consulta/normas , Encaminhamento e Consulta/estatística & dados numéricos , Inquéritos e Questionários , Revisão da Utilização de Recursos de Saúde/estatística & dados numéricos
4.
Nat Genet ; 20(2): 129-35, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9771704

RESUMO

X-linked lymphoproliferative syndrome (XLP or Duncan disease) is characterized by extreme sensitivity to Epstein-Barr virus (EBV), resulting in a complex phenotype manifested by severe or fatal infectious mononucleosis, acquired hypogammaglobulinemia and malignant lymphoma. We have identified a gene, SH2D1A, that is mutated in XLP patients and encodes a novel protein composed of a single SH2 domain. SH2D1A is expressed in many tissues involved in the immune system. The identification of SH2D1A will allow the determination of its mechanism of action as a possible regulator of the EBV-induced immune response.


Assuntos
Proteínas de Transporte/genética , Infecções por Herpesviridae/complicações , Herpesvirus Humano 4 , Peptídeos e Proteínas de Sinalização Intracelular , Transtornos Linfoproliferativos/genética , Mutação , Domínios de Homologia de src/genética , Antígenos CD , Linfócitos B/imunologia , Linfócitos B/virologia , Proteínas de Transporte/metabolismo , Clonagem Molecular , Feminino , Ligação Genética , Glicoproteínas/metabolismo , Infecções por Herpesviridae/imunologia , Infecções por Herpesviridae/virologia , Humanos , Imunoglobulinas/metabolismo , Transtornos Linfoproliferativos/complicações , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/virologia , Masculino , Dados de Sequência Molecular , Linhagem , Receptores de Superfície Celular , Alinhamento de Sequência , Deleção de Sequência , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária , Membro 1 da Família de Moléculas de Sinalização da Ativação Linfocitária , Linfócitos T/imunologia , Linfócitos T/virologia , Cromossomo X
5.
Klin Padiatr ; 223(6): 378-85, 2011 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-22052638

RESUMO

BACKGROUND: Primary immunodeficiencies are potentially life-threatening diseases. Over the last years, the clinical phenotype and the molecular basis of an increasing number of immunological defects have been characterized. However, in daily practice primary immunodeficiencies are still often diagnosed too late. Considering that an early diagnosis may reduce morbidity and mortality of affected patients, an interdisciplinary guideline for the diagnosis of primary immunodeficiencies was developed on behalf of the Arbeitsgemeinschaft Pädiatrische Immunologie (API) and the Deutsche Gesellschaft für Immunologie (DGfI). METHODS: The guideline is based on expert opinion and on knowledge from other guidelines and recommendations from Germany and other countries, supplemented by data from studies that support the postulated key messages (level of evidence III). With the contribution of 20 representatives, belonging to 14 different medical societies and associations, a consensus-based guideline with a representative group of developers and a structured consensus process was created (S2k). Under the moderation of a representative of the Association of the Scientific Medical Societies in Germany (AWMF) the nominal group process took place in April 2011. RESULTS: The postulated key messages were discussed and voted on following a structured consensus procedure. In particular, modified warning signs for primary immunodeficiencies were formulated and immunological emergency situations were defined.


Assuntos
Comportamento Cooperativo , Síndromes de Imunodeficiência/diagnóstico , Comunicação Interdisciplinar , Adulto , Criança , Diagnóstico Precoce , Medicina Baseada em Evidências , Alemanha , Humanos , Infecções Oportunistas/diagnóstico
6.
Clin Immunol ; 137(3): 357-65, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20832369

RESUMO

Autoimmune lymphoproliferative syndrome (ALPS) is mainly caused by defects in the CD95 pathway. Raised CD3+TCRαß+CD4-CD8- double negative T cells and impaired T cell apoptosis are hallmarks of the disease. In contrast, the B cell compartment has been less well studied. We found an altered distribution of B cell subsets with raised transitional B cells and reduced marginal zone B cells, switched memory B cells and plasma blasts in most of 22 analyzed ALPS patients. Moreover, 5 out of 66 ALPS patients presented with low IgG and susceptibility to infection revealing a significant overlap between ALPS and common variable immunodeficiency (CVID). In patients presenting with lymphoproliferation, cytopenia, hypogammaglobulinemia and impaired B cell differentiation, serum biomarkers were helpful in addition to apoptosis tests for the identification of ALPS patients. Our observations may indicate a role for apoptosis defects in some diseases currently classified as CVID.


Assuntos
Síndrome Linfoproliferativa Autoimune/diagnóstico , Síndrome Linfoproliferativa Autoimune/imunologia , Linfócitos B/imunologia , Imunodeficiência de Variável Comum/diagnóstico , Imunodeficiência de Variável Comum/imunologia , Proteína Ligante Fas/sangue , Interleucina-10/sangue , Vitamina B 12/sangue , Adolescente , Adulto , Agamaglobulinemia/imunologia , Apoptose , Biomarcadores/sangue , Criança , Pré-Escolar , Diagnóstico Diferencial , Proteína Ligante Fas/imunologia , Citometria de Fluxo , Humanos , Imunoglobulina G/sangue , Interleucina-10/imunologia , Pessoa de Meia-Idade , Monócitos/imunologia , Fenótipo , Linfócitos T/imunologia , Vitamina B 12/imunologia , Receptor fas/sangue , Receptor fas/imunologia
7.
Infection ; 38(3): 231-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20358246

RESUMO

CASE PRESENTATION: We report on the case of a 5 year-old girl who developed fulminant myocarditis due to acute infection with influenza virus type B. Cardiac arrest occurred suddenly, resuscitation efforts were not successful, and the patient died of congestive heart failure 24 h after admission to the hospital. DIAGNOSIS: Lymphocytic infiltration of cardiac tissues and virologic studies confirmed the suspected diagnosis of acute viral myocarditis. CONCLUSION: In conclusion, influenza virus type B is one of the infective agents that can cause rapid and fatal myocarditis in previously healthy children. Early cardiac support may be the only option to prevent fatal outcome.


Assuntos
Vírus da Influenza B/isolamento & purificação , Influenza Humana/virologia , Miocardite/virologia , Doença Aguda , Fatores Etários , Pré-Escolar , Evolução Fatal , Feminino , Histocitoquímica , Humanos , Vírus da Influenza B/genética , Influenza Humana/líquido cefalorraquidiano , Influenza Humana/diagnóstico , Miocardite/líquido cefalorraquidiano , Miocardite/diagnóstico , Radiografia Torácica , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Science ; 268(5212): 866-9, 1995 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-7754369

RESUMO

Carrier-mediated prostaglandin transport has been postulated to occur in many tissues. On the basis of sequence homology, the protein of unknown function encoded by the rat matrin F/G complementary DNA was predicted to be an organic anion transporter. Expression of the matrin F/G complementary DNA in HeLa cells or Xenopus oocytes conferred the property of specific transport of prostaglandins. The tissue distribution of matrin F/G messenger RNA and the sensitivity of matrin F/G-induced prostaglandin transport to inhibitors were similar to those of endogenous prostaglandin transport. The protein encoded by the matrin F/G complementary DNA is thus preferably called PGT because it is likely to function as a prostaglandin transporter.


Assuntos
Antiporters , Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Prostaglandinas/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Transporte Biológico/efeitos dos fármacos , Proteínas de Transporte/química , Proteínas de Transporte/genética , Códon , Colo/metabolismo , DNA Complementar/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Epitélio/metabolismo , Células HeLa , Humanos , Medula Renal/metabolismo , Dados de Sequência Molecular , Transportadores de Ânions Orgânicos , RNA Mensageiro/análise , Ratos , Xenopus
9.
Klin Padiatr ; 221(6): 379-81, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19890791

RESUMO

We report on a 22-year-old girl with a history of recurrent febrile episodes, chronic arthritis, urticarial rash, and neurological symptoms including right hemiparesis, internal hydrocephalus, mental retardation, progressive deafness, and visual impairment. Treatment starting at age 20 months, including different combinations of immunosuppressive and antiinflammatory drugs such as corticosteroids and anti-TNFalpha antibody, was unsuccessful. Four years ago, we found a heterozygous S595G mutation in the NLRP3 gene of this patient. This prompted us to introduce anakinra, which resulted in considerable improvement of the patient's complaints.


Assuntos
Alelos , Proteínas de Transporte/genética , Síndromes Periódicas Associadas à Criopirina/genética , Análise Mutacional de DNA , Triagem de Portadores Genéticos , Adolescente , Antirreumáticos/uso terapêutico , Criança , Pré-Escolar , Síndromes Periódicas Associadas à Criopirina/diagnóstico , Síndromes Periódicas Associadas à Criopirina/tratamento farmacológico , Síndromes Periódicas Associadas à Criopirina/imunologia , Feminino , Seguimentos , Humanos , Lactente , Proteína Antagonista do Receptor de Interleucina 1/deficiência , Proteína Antagonista do Receptor de Interleucina 1/uso terapêutico , Interleucina-1beta/sangue , Proteína 3 que Contém Domínio de Pirina da Família NLR , Adulto Jovem
10.
Lancet ; 370(9601): 1757-63, 2007 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-18037080

RESUMO

BACKGROUND: We aimed to assess the efficacy of the oral live attenuated human rotavirus vaccine Rotarix (RIX4414) for prevention of rotavirus gastroenteritis in European infants during their first 2 years of life. METHODS: 3994 study participants were enrolled from six countries and were randomly assigned two oral doses of either RIX4414 (n=2646) or placebo (n=1348), which were coadministered with the first two doses of specific childhood vaccinations. Follow-up for gastroenteritis episodes was undertaken from 2 weeks post-dose two through the two consecutive rotavirus seasons following vaccinations (combined efficacy follow-up period; mean duration 17 months [SD 1.6]). Our primary endpoint was vaccine efficacy against rotavirus gastroenteritis of any severity during the first efficacy follow-up period (2 weeks post-dose two to the end of the first rotavirus season). Stool specimens obtained during gastroenteritis episodes were tested for rotavirus by ELISA and typed by RT-PCR. Episodes scoring 11 or greater on the 20-point Vesikari scale were classified as severe. Analysis was according to protocol. This study is registered with ClinicalTrials.gov, number NCT00140686 (eTrack102247). FINDINGS: 120 infants were excluded from the according-to-protocol analysis. During the first efficacy follow-up period (mean duration 5.7 months [SD 1.2]), 24 of 2572 infants allocated RIX4414 versus 94 of 1302 given placebo had rotavirus gastroenteritis episodes of any severity, resulting in a vaccine efficacy of 87.1% (95% CI 79.6-92.1; p<0.0001). For the combined efficacy follow-up period, vaccine efficacy against severe rotavirus gastroenteritis was 90.4% (85.1-94.1; p<0.0001), for admission owing to rotavirus gastroenteritis 96.0% (83.8-99.5; p<0.0001), and for rotavirus-related medical attention 83.8% (76.8-88.9; p<0.0001), and significant protection against severe rotavirus gastroenteritis by circulating G1, G2, G3, G4, and G9 rotavirus types was shown. INTERPRETATION: In a European setting, two doses of RIX4414 coadministered with childhood vaccines provided high protection against any and severe rotavirus gastroenteritis, with an overall reduction of admissions for gastroenteritis over two consecutive rotavirus epidemic seasons.


Assuntos
Gastroenterite , Infecções por Rotavirus/prevenção & controle , Vacinas contra Rotavirus , Vacinas Atenuadas , Método Duplo-Cego , Europa (Continente)/epidemiologia , Fezes/virologia , Feminino , Gastroenterite/classificação , Gastroenterite/prevenção & controle , Gastroenterite/virologia , Humanos , Lactente , Masculino , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/fisiopatologia , Índice de Gravidade de Doença
14.
J Clin Invest ; 75(6): 2056-64, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2989340

RESUMO

We studied the effects of cyclic AMP (cAMP) on HCO-3 transport by rabbit cortical collecting tubules perfused in vitro. Net HCO-3 secretion was observed in tubules from NaHCO3- loaded rabbits. 8-Bromo-cAMP-stimulated net HCO-3 secretion, whereas secretion fell with time in control tubules. Both isoproterenol and vasopressin (ADH) are known to stimulate adenylate cyclase in this epithelium; however, only isoproterenol stimulated net HCO-3 secretion. The mechanism of cAMP-stimulated HCO-3 secretion was examined. If both HCO-3 and H+ secretion were to occur simultaneously in tubules exhibiting net HCO-3 secretion, cAMP might increase the net HCO-3 secretory rate by inhibiting H+ secretion, by stimulating HCO-3 secretion, or both. These possibilities were examined using basolateral addition of the disulfonic stilbene (4,4'-diisothiocyanostilbene-2,2'-disulfonate (DIDS). In acidifying tubules from NH4Cl-loaded rabbits, DIDS eliminated HCO-3 reabsorption, a result consistent with known effects of DIDS as an inhibitor of H+ secretion. In contrast, cAMP left acidification (H+ secretion) intact. DIDS applied to HCO-3 secretory tubules failed to increase the HCO-3 secretory rate, indicating minimal H+ secretion in HCO-3 secreting tubules. Thus, inhibition of H+ secretion by cAMP could not account for the cAMP-induced stimulation of net HCO-3 secretion. cAMP-stimulated HCO-3 secretion was reversibly eliminated by 0 Cl perfusate, whereas luminal DIDS had no effect. Bath amiloride (1 mM) failed to eliminate cAMP-stimulated HCO-3 secretion when bath [Na+] was 145 mM or 5 mM. cAMP depolarized the transepithelial voltage. The collected fluid [HCO-3] after cAMP could be accounted for by electrical driving forces, suggesting that cAMP stimulates passive HCO-3 secretion. However, cAMP did not alter HCO-3 permeability measured under conditions expected to inhibit transcellular HCO-3 movement (0 Cl- solutions and bath DIDS). This measured HCO-3 permeability was not high enough to account, by passive diffusion, for the HCO-3 fluxes observed in Cl-containing solutions. We conclude the following: cAMP increased net HCO3- secretion by stimulating HCO3- secretion and not by inhibiting H+ secretion; this HCO3- secretion may have occurred by Cl-HCO3- exchange; Na+-H+ exchange appeared not to play a role in basolateral H+ extrusion under these conditions; and the stimulation of HCO3- secretion by isoproterenol, but not ADH, suggests the existence of separate cell cAMP pools or cellular heterogeneity in this cAMP response.


Assuntos
Bicarbonatos/metabolismo , AMP Cíclico/fisiologia , Túbulos Renais Coletores/metabolismo , Túbulos Renais/metabolismo , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/análogos & derivados , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Equilíbrio Ácido-Base/efeitos dos fármacos , Amilorida/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Cloretos/metabolismo , Feminino , Isoproterenol/farmacologia , Coelhos , Taxa Secretória/efeitos dos fármacos , Trocadores de Sódio-Hidrogênio , Vasopressinas/farmacologia
15.
J Clin Invest ; 78(6): 1621-30, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3023449

RESUMO

Cyclic AMP stimulates HCO3 secretion and Cl self-exchange in rabbit cortical collecting tubule. We found that varying peritubular [Cl] changed the Cl self-exchange rate with saturation kinetics (Km, 3-4 mM). HCO3 secretion also showed saturation kinetics as a function of mean luminal [Cl] (Km, 4-11 mM). Both Cl self-exchange and Cl-HCO3 exchange thus appear to be carrier-mediated. Addition/removal of basolateral HCO3 qualitatively changed Cl and HCO3 transport as expected for Cl-HCO3 exchange, but quantitatively changed Cl absorption more than HCO3 secretion. The diffusive Cl permeability and the transepithelial conductance in the presence of HCO3/CO2 and cAMP were higher than in their absence suggesting that HCO3/CO2 and cAMP together increase a conductive Cl pathway parallel to a 1:1 Cl-HCO3 exchanger. Thus, cAMP not only stimulates the overall process of anion exchange (probably by increasing an electroneutral exchanger and/or a series Cl conductance), but also stimulates a Cl conductance parallel to the exchange process.


Assuntos
Bicarbonatos/metabolismo , Cloretos/metabolismo , AMP Cíclico/farmacologia , Túbulos Renais Coletores/metabolismo , Túbulos Renais/metabolismo , Absorção , Animais , Transporte Biológico/efeitos dos fármacos , Córtex Renal/metabolismo , Túbulos Renais Coletores/efeitos dos fármacos , Cinética , Permeabilidade , Coelhos
16.
J Clin Invest ; 82(1): 57-64, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3392216

RESUMO

Cl self-exchange by the rabbit cortical collecting tubule (CCT) occurs via an apical anion exchanger in series with a basolateral Cl conductance. We studied the effects of organic acids on CCT Cl self-exchange. We found no evidence for transport of acid anions by the self-exchange system. Rather, Cl self-exchange was inhibited by a variety of organic acids. The degree of inhibition correlated with the chloroform/water partition coefficient and was enhanced by lowering pH, indicating inhibition by the lipid-soluble, protonated species. Inhibition by the representative acid iso-butyrate was dose-dependent and showed sidedness (basolateral greater than apical). Iso-butyrate also reversibly reduced transepithelial conductance without altering K permeability, suggesting inhibition of the principal cell basolateral Cl conductance. Because small organic compounds with similar lipid solubilities but no carboxyl group had no effect, both the carboxyl group and the lipid-solubility of organic acids appear to be important. The results are consistent with blockade of chloride channels by organic acids.


Assuntos
Cloretos/metabolismo , Ácidos Graxos/farmacologia , Túbulos Renais Coletores/metabolismo , Túbulos Renais/metabolismo , 1-Butanol , Animais , Transporte Biológico/efeitos dos fármacos , Butanóis/farmacologia , Butiratos/farmacologia , Caprilatos/farmacologia , Clorofórmio , Depressão Química , Condutividade Elétrica , Concentração de Íons de Hidrogênio , Isobutiratos , Túbulos Renais Coletores/efeitos dos fármacos , Cinética , Naloxona/farmacologia , Coelhos , Ácido gama-Aminobutírico/farmacologia
17.
J Clin Invest ; 98(5): 1142-9, 1996 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8787677

RESUMO

We recently identified a cDNA in the rat that encodes a broadly expressed PG transporter (PGT). Because PGs play diverse and important roles in human health and disease, we cloned human PGT (hPGT) from an adult human kidney cDNA library. A consensus sequence (4.0 kb) derived from several clones, plus 3' polymerase chain reaction amplification, exhibited 74% nucleic acid identity and 82% amino acid identity compared to rat PGT. When transiently expressed in HeLa cells, a full-length clone catalyzed the transport of PGE1, PGE2, PGD2, PGF2alpha, and, to a lesser degree, TXB2. Northern blotting revealed mRNA transcripts of many different sizes in adult human heart, placenta, brain, lung, liver, skeletal muscle, pancreas, kidney, spleen, prostate, ovary, small intestine, and colon. hPGT mRNAs are also strongly expressed in human fetal brain, lung, liver, and kidney. The broad tissue distribution and substrate profile of hPGT suggest a role in the transport and/or metabolic clearance of PGs in diverse human tissues.


Assuntos
Antiporters/genética , Proteínas de Ligação a DNA/genética , Prostaglandinas/metabolismo , Sequência de Aminoácidos , Animais , Antiporters/biossíntese , Transporte Biológico , Clonagem Molecular , Sequência Consenso , DNA Complementar , Proteínas de Ligação a DNA/biossíntese , Feto , Biblioteca Gênica , Humanos , Dados de Sequência Molecular , Transportadores de Ânions Orgânicos , Ratos , Proteínas Recombinantes/biossíntese , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Distribuição Tecidual
18.
J Clin Invest ; 73(6): 1659-67, 1984 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6427278

RESUMO

Although intrarenal infusions of kinins produce diuresis, it is not clear to what extent this response is due to hemodynamically mediated medullary washout and/or to direct epithelial effects of kinins. Recent evidence has shown that bradykinin binds to collecting tubules in vitro. We therefore examined the interactions of lysyl-bradykinin and antidiuretic hormone (ADH) with respect to hydraulic conductivity (Lp) in the rabbit cortical collecting tubule perfused in vitro. To ensure adequate substrate for prostaglandin synthesis, the bath contained 2.5 microM arachidonic acid. Arachidonic acid produced no change in base-line Lp and had no effect on the subsequent response to a supramaximal dose of ADH (100 microU/ml). Therefore, all subsequent experiments were done in the presence of arachidonic acid. Lysyl-bradykinin (10(-9)M) added to either the lumen or bath had no effect on base-line Lp. Collecting tubules which were exposed for 1 h to bath lysyl-bradykinin (10(-9)M) had a significantly diminished subsequent Lp in response to ADH (P less than 0.02). In tubules exposed to bath lysyl-bradykinin plus indomethacin (5 microM), the subsequent ADH response was normal. Lysyl-bradykinin (10(-9)M) added to the lumen had no effect on subsequent ADH response. We conclude that lysyl-bradykinin from the basolateral side inhibits the hydroosmotic response of the cortical collecting tubule to ADH, and that this inhibition is probably prostaglandin-mediated. Lysyl-bradykinin does not affect water flow from the luminal surface. These data indicate that the diuresis seen with kinin infusions may result, at least in part, from a direct epithelial effect. They also suggest a role of the renal kallikrein-kinin system in modulating water transport in vivo.


Assuntos
Calidina/farmacologia , Córtex Renal/fisiologia , Túbulos Renais/fisiologia , Vasopressinas/farmacologia , Animais , Ácido Araquidônico , Ácidos Araquidônicos/farmacologia , Água Corporal/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Feminino , Indometacina/farmacologia , Córtex Renal/efeitos dos fármacos , Túbulos Renais/efeitos dos fármacos , Perfusão , Coelhos
19.
J Clin Invest ; 73(2): 507-15, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6699174

RESUMO

Numerous previous studies have proposed a role for angiotensin II (AII) in the renal regulation of salt balance. At least one nephron site, the proximal convoluted segment, has been implicated in this role. We used in vitro microperfusion of rabbit proximal convoluted tubules to further examine this question. To insure use of appropriate in vivo concentrations as well as potency of the hormone in vitro, we measured plasma AII levels by radioimmunoassay in normal, sodium-depleted, and adrenalectomized rabbits, and measured AII activity by bioassay after incubation in various microperfusion baths. Plasma levels ranged from approximately 2 X 10(-11) to 5 X 10(-11) M. AII activity was stable in Ringer's solution plus albumin, but not in rabbit serum or Ringer's solution plus fetal calf serum. In Ringer's solution plus albumin, physiologic concentrations of AII stimulated volume reabsorption (Jv). 10(-11) M AII increased Jv by 16% (P less than 0.01). 10(-10) M AII produced a lesser increase, 7.5% (P less than 0.05). At a frequently studied, but probably pharmacologic dose, 10(-7) M AII inhibited Jv by 24% (P less than 0.001). AII at 10(-11) M did not stimulate Jv in the presence of 10(-7) M saralasin. Though previous studies have suggested agonistic effects of saralasin alone in epithelia, we found no significant effect of 10(-7) M saralasin on Jv. None of the AII doses measurably changed transepithelial voltage. We conclude that AII in physiologic doses directly stimulates Jv in proximal convoluted tubules and this effect is probably receptor mediated and, within the limits of detection, electroneutral.


Assuntos
Angiotensina II/farmacologia , Túbulos Renais Proximais/metabolismo , Sódio/metabolismo , Absorção , Animais , Transporte Biológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Feminino , Técnicas In Vitro , Túbulos Renais Proximais/efeitos dos fármacos , Perfusão , Coelhos , Saralasina/farmacologia
20.
J Thromb Haemost ; 5(12): 2315-22, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17900274

RESUMO

Plasminogen (plg) deficiency has been classified as (i) hypoplasminogenemia or 'true' type I plg deficiency, and (ii) dysplasminogenemia, also called type II plg deficiency. Both forms, severe hypoplasminogenemia and dysplasminogenemia, are not causally linked to venous thrombosis. Dysplasminogenemia does not lead to a specific clinical manifestation and probably represents only a polymorphic variation in the general population, mainly in Asian countries. Severe hypoplasminogenemia is associated with compromised extracellular fibrin clearance during wound healing, leading to pseudomembraneous (ligneous) lesions on affected mucous membranes (eye, middle ear, mouth, pharynx, duodenum, upper and lower respiratory tract and female genital tract). Ligneous conjunctivitis is by far the most common clinical manifestation. More than 12% of patients with severe hypoplasminogenemia exhibit congenital occlusive hydrocephalus. In milder cases of ligneous conjunctivitis, topical application of plg-containing eye drops, fresh frozen plasma, heparin, corticosteroids or certain immunosuppressive agents (such as azathioprine) may be more or less effective. Oral treatment with sex hormones was successful in two female patients with ligneous conjunctivitis. In severe cases with possibly life-threatening multi-organ involvement, true therapeutic options are not available at present. The plg-knockout mouse is a useful tool to study the many different properties of plg in a variety of settings, such as wound healing, tissue repair and tissue remodeling, virulence and invasiveness of certain bacteria in the human host, tumor growth and dissemination, as well as arteriosclerosis.


Assuntos
Transtornos da Coagulação Sanguínea , Conjuntivite/etiologia , Fibrinólise , Plasminogênio/deficiência , Trombose Venosa/etiologia , Sequência de Aminoácidos , Animais , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/classificação , Transtornos da Coagulação Sanguínea/complicações , Transtornos da Coagulação Sanguínea/tratamento farmacológico , Transtornos da Coagulação Sanguínea/epidemiologia , Transtornos da Coagulação Sanguínea/genética , Modelos Animais de Doenças , Fibrinolisina/metabolismo , Predisposição Genética para Doença , Heterozigoto , Homozigoto , Humanos , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Mutação , Fenótipo , Plasminogênio/química , Plasminogênio/genética , Conformação Proteica , Medição de Risco , Fatores de Risco
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