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2.
J Neurol ; 267(6): 1622-1631, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32055996

RESUMO

OBJECTIVE: Observational study to evaluate the long-term motor and non-motor effects of deep brain stimulation (DBS) of the globus pallidus internus (GPi) on medically refractory dystonia. BACKGROUND: Dystonia is a chronic disease affecting mainly young patients with a regular life expectancy and lifelong need for therapy. Pallidal DBS is an established treatment for severe isolated dystonia but long-term data are sparse. METHODS: We considered 36 consecutive patients with isolated generalized (n = 14) and cervical/segmental (n = 22) dystonia operated at Charité-University Hospital between 2000 and 2007 in a retrospective analysis for long-term outcome of pallidal DBS. In 19 of these patients, we could analyze dystonic symptoms and disability rated by the Burke-Fahn-Marsden Dystonia Rating scale (BFMDRS) at baseline, short-term (ST-FU, range 3-36 months) and long-term follow-up (LT-FU, range 93-197 months). Quality of life and mood were evaluated using the SF36 and Beck Depression Index (BDI) questionnaires. RESULTS: Patients reached an improvement in motor symptoms of 63.8 ± 5.7% (mean ± SE) at ST-FU and 67.9 ± 6.1% at LT-FU. Moreover, a significant and stable reduction in disability was shown following DBS (54.2 ± 9.4% at ST-FU and 53.8 ± 9.2% at LT-FU). BDI and SF36 had improved by 40% and 23%, respectively, at LT-FU (n = 14). Stimulation-induced adverse events included swallowing difficulties, dysarthria, and bradykinesia. Pulse generator (n = 3) and electrodes (n = 5) were revised in seven patients due to infection. CONCLUSIONS: Pallidal DBS is a safe and efficacious long-term treatment for dystonia with sustained effects on motor impairment and disability, accompanied by a robust improvement in mood and quality of life.


Assuntos
Estimulação Encefálica Profunda , Distúrbios Distônicos/terapia , Globo Pálido , Avaliação de Resultados em Cuidados de Saúde , Torcicolo/terapia , Adulto , Sintomas Afetivos/terapia , Idoso , Estimulação Encefálica Profunda/efeitos adversos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Estudos Retrospectivos , Índice de Gravidade de Doença , Adulto Jovem
3.
Neuroimage Clin ; 16: 175-183, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28794978

RESUMO

Parkinsonian bradykinesia and rigidity are typically associated with excessive beta band oscillations in the subthalamic nucleus. Recently another spectral peak has been identified that might be implicated in the pathophysiology of the disease: high-frequency oscillations (HFO) within the 150-400 Hz range. Beta-HFO phase-amplitude coupling (PAC) has been found to correlate with severity of motor impairment. However, the neuronal origin of HFO and its usefulness as a potential target for deep brain stimulation remain to be established. For example, it is unclear whether HFO arise from the same neural populations as beta oscillations. We intraoperatively recorded local field potentials from the subthalamic nucleus while advancing DBS electrodes in 2 mm steps from 4 mm above the surgical target point until 2 mm below, resulting in 4 recording sites. Data from 26 nuclei from 14 patients were analysed. For each trajectory, we identified the recording site with the largest spectral peak in the beta range (13-30 Hz), and the largest peak in the HFO range separately. In addition, we identified the recording site with the largest beta-HFO PAC. Recording sites with largest beta power and largest HFO power coincided in 50% of cases. In the other 50%, HFO was more likely to be detected at a more superior recording site in the target area. PAC followed more closely the site with largest HFO (45%) than beta power (27%). HFO are likely to arise from spatially close, but slightly more superior neural populations than beta oscillations. Further work is necessary to determine whether the different activities can help fine-tune deep brain stimulation targeting.


Assuntos
Ritmo beta , Doença de Parkinson/fisiopatologia , Núcleo Subtalâmico/fisiopatologia , Idoso , Ondas Encefálicas , Estimulação Encefálica Profunda , Humanos , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador
4.
Ann Rheum Dis ; 69(2): 443-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19293161

RESUMO

OBJECTIVES: (1) To show that a single-chain Fv antibody (scFv) against tumour necrosis factor alpha (TNFalpha) (ESBA105) has efficacy comparable to a full length anti-TNFalpha IgG (infliximab); (2) to evaluate whether ESBA105 has all the properties required for the local treatment of arthritis; and (3) to investigate its discriminative tissue penetration properties. METHODS: In vivo efficacy was measured in arthritis of the knee joint induced by the intra-articular injection of recombinant human TNFalpha (rhTNFalpha) in Lewis rats. Cartilage penetration of scFv (ESBA105) and full length IgG (infliximab) were studied in bovine cartilage specimens ex vivo. Tissue penetration, biodistribution and pharmacokinetics of ESBA105 were followed and compared after intra-articular and intravenous administration. RESULTS: In cell culture, ESBA105 showed similar TNFalpha inhibitory potency to infliximab. In vivo, ESBA105 inhibited rhTNFalpha-induced synovial inflammation in rats with efficacy again comparable to infliximab. An 11-fold molar excess of ESBA105 over rhTNFalpha resulted in 90% inhibition of knee joint swelling, inflammatory infiltrates and proteoglycan loss from cartilage. In ex vivo studies of bovine cartilage, ESBA105 penetrated well into the cartilage whereas infliximab remained on the surface. In vivo, rapid penetration into the synovial tissue, cartilage and surrounding tissues was observed following intra-articular injection of [(125)I]-ESBA105 into the knee joint of rabbits. CONCLUSIONS: ESBA105 potently inhibits inflammation and prevents cartilage damage triggered by TNFalpha. In contrast to a full length IgG, ESBA105 also penetrates into cartilage and can be expected to reverse the TNFalpha-induced catabolic state of articular cartilage in arthritides.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Artrite Experimental/prevenção & controle , Osteoartrite/prevenção & controle , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacologia , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/farmacologia , Apoptose/efeitos dos fármacos , Cartilagem Articular/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Fibroblastos/efeitos dos fármacos , Infliximab , Injeções Intra-Articulares , Masculino , Coelhos , Ratos , Ratos Endogâmicos Lew , Proteínas Recombinantes/farmacologia , Sinovite/prevenção & controle , Distribuição Tecidual
5.
Acta Physiol (Oxf) ; 188(1): 33-40, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16911251

RESUMO

BACKGROUND: Angiotensin II (Ang II) is a well-known activator of smooth muscle in the vasculature but has been little explored with regard to intestinal wall muscular activity. This study investigates pharmacological properties of Ang II and expression of its receptors in small-intestinal smooth muscle from rats and humans. METHODS: Isometric recordings were performed in vitro on small intestinal longitudinal muscle strips. Protein expressions of Ang II typ 1 (AT1R) and typ 2 (AT2R) receptors were assessed by Western blot. RESULTS: Ang II elicited concentration-dependent contractions of rat jejunal and ileal muscle preparations. The concentration-response curve (rat ileum, EC(50): 1.5 +/- 0.9 x 10(-8) M) was shifted to the right by the AT1R receptor antagonist losartan (10(-7) M) but was unaffected by the AT2R antagonist PD123319 (10(-7) M) as well as by the adrenolytic guanethidine (3 x 10(-6) M) and the anticholinergic atropine (10(-6) M). Human duodenal, jejunal and ileal longitudinal muscle preparations all contracted concentration-dependently in response to Ang II. The concentration-response curve (human jejunum, EC(50): 1.5 +/- 0.8 x 10(-8) M) was shifted to the right by losartan (10(-7) M) but was unaffected by PD123319 (10(-7) M). Both AT1R and AT2R were detected in all segments of the rat small intestinal wall musculature, whereas only AT1R was readily detectable in the human samples. CONCLUSION: Ang II elicits contractions of small-intestinal longitudinal muscle preparations from the small intestine of rats and man. The pharmacological pattern and protein expression analyses indicate mediation via the AT1R.


Assuntos
Angiotensina II/farmacologia , Intestino Delgado/fisiologia , Músculo Liso/fisiologia , Antagonistas Adrenérgicos/farmacologia , Adulto , Idoso , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Bloqueadores do Receptor Tipo 2 de Angiotensina II , Animais , Atropina/farmacologia , Western Blotting/métodos , Antagonistas Colinérgicos/farmacologia , Relação Dose-Resposta a Droga , Feminino , Guanetidina/farmacologia , Humanos , Imidazóis/farmacologia , Técnicas In Vitro , Intestino Delgado/efeitos dos fármacos , Losartan/farmacologia , Masculino , Pessoa de Meia-Idade , Contração Muscular/efeitos dos fármacos , Músculo Liso/química , Músculo Liso/efeitos dos fármacos , Piridinas/farmacologia , Ratos , Receptor Tipo 1 de Angiotensina/análise , Receptor Tipo 2 de Angiotensina/análise , Especificidade da Espécie
6.
Exp Physiol ; 91(1): 191-9, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16263801

RESUMO

Activation of angiotensin II type 2 receptors (AT2R) has been shown to stimulate duodenal mucosal alkaline secretion (DMAS) in Sprague-Dawley rats (S-D). This finding could not be confirmed in another line of S-D, and the present study investigates whether the level of AT2R expression determines the response to the AT2R agonist CGP42112A. DMAS was measured in anaesthetized rats using in situ pH-stat titration. Real-time PCR and Western blot were used to assess AT1R and AT2R RNA and protein expression, respectively. CGP42112A (0.1 microg kg(-1)min(-1) I.V.) elicited a 45% net increase in DMAS in the previous S-D line studied, whereas no change occurred in the new S-D line. Luminal administration of prostaglandin E2 (10(-5) M) increased DMAS similarly in both S-D lines. AT2R protein expression was significantly higher in tissue from the previous line compared to the new line. Individual AT1R to AT2R ratios (RNA and protein) were significantly higher in the new line compared to the previous S-D line. In the new S-D line intravenous infusion of angiotensin II (Ang II; 10 microg kg(-1) h(-1)) over 120 min significantly lowered the duodenal AT1aR to AT2R RNA ratio. Prolonged Ang II infusion over 240 min increased AT2R protein expression and evoked a 42% stimulatory response in DMAS to CGP42112A. The level of local AT2R expression determines the effect of the AT2R agonist CGP42112A on rat duodenal mucosal alkaline secretion. AT2R expression should be confirmed before interpreting the experimental effects of pharmacological interferences with this receptor.


Assuntos
Duodeno/metabolismo , Mucosa Intestinal/metabolismo , RNA Mensageiro/metabolismo , Receptor Tipo 2 de Angiotensina/agonistas , Angiotensina II/farmacologia , Animais , Dinoprostona/farmacologia , Duodeno/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Masculino , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 2 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/metabolismo
7.
Acta Anaesthesiol Scand ; 48(2): 198-204, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14995942

RESUMO

BACKGROUND: Blockade of the angiotensin II type 1 (AT1) receptor has been demonstrated to ameliorate splanchnic hypoperfusion in acute experimental circulatory failure. This study focused on hemodynamic changes and survival in pigs treated with AT1 blockade prior to or during acute endotoxinemia. METHODS: Escherichia coli lipopolysaccharide endotoxin was infused in anesthetized and mechanically ventilated pigs. Systemic, renal, mesenteric and jejunal mucosal perfusion as well as systemic oxygen and acid-base balance were monitored. The selective AT1 receptor blocker candesartan was administered prior to as well as during endotoxinemia. Control animals received the saline vehicle. RESULTS: Pre-treatment with candesartan resulted in higher survival rate (83%, 10 out of 12 animals) compared with 50% (6 of 12) in control animals and 27% (3 of 11) in animals treated during endotoxinemia. Pre-treatment with candesartan resulted in higher cardiac output, mixed venous oxygen saturation, arterial standard base-excess, portal venous blood flow during endotoxin infusion compared with controls and animals treated during endotoxinemia. No adverse effects were found on neither systemic nor renal circulation. CONCLUSION: The favorable results of AT1 receptor blockade prior to endotoxinemia are lost when blockade is established during endotoxinemia demonstrating the importance of the renin-angiotensin system and its dynamic involvement in acute endotoxinemic shock.


Assuntos
Antagonistas de Receptores de Angiotensina , Benzimidazóis/farmacologia , Endotoxemia/tratamento farmacológico , Circulação Esplâncnica/efeitos dos fármacos , Tetrazóis/farmacologia , Doença Aguda , Animais , Compostos de Bifenilo , Débito Cardíaco/efeitos dos fármacos , Endotoxemia/mortalidade , Endotoxemia/fisiopatologia , Feminino , Masculino , Oxigênio/sangue , Sistema Renina-Angiotensina/fisiologia , Taxa de Sobrevida , Suínos
8.
EMBO J ; 20(11): 2943-53, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11387227

RESUMO

In mouse brain cDNA libraries generated from small RNA molecules we have identified a total of 201 different expressed RNA sequences potentially encoding novel small non-messenger RNA species (snmRNAs). Based on sequence and structural motifs, 113 of these RNAs can be assigned to the C/D box or H/ACA box subclass of small nucleolar RNAs (snoRNAs), known as guide RNAs for rRNA. While 30 RNAs represent mouse homologues of previously identified human C/D or H/ACA snoRNAs, 83 correspond to entirely novel snoRNAS: Among these, for the first time, we identified four C/D box snoRNAs and four H/ACA box snoRNAs predicted to direct modifications within U2, U4 or U6 small nuclear RNAs (snRNAs). Furthermore, 25 snoRNAs from either class lacked antisense elements for rRNAs or snRNAS: Therefore, additional snoRNA targets have to be considered. Surprisingly, six C/D box snoRNAs and one H/ACA box snoRNA were expressed exclusively in brain. Of the 88 RNAs not belonging to either snoRNA subclass, at least 26 are probably derived from truncated heterogeneous nuclear RNAs (hnRNAs) or mRNAS: Short interspersed repetitive elements (SINEs) are located on five RNA sequences and may represent rare examples of transcribed SINES: The remaining RNA species could not as yet be assigned either to any snmRNA class or to a part of a larger hnRNA/mRNA. It is likely that at least some of the latter will represent novel, unclassified snmRNAS:


Assuntos
Técnicas Genéticas , Camundongos/genética , RNA/química , RNA/genética , Animais , Pareamento de Bases , Sequência de Bases , Encéfalo/metabolismo , DNA Complementar , Bases de Dados como Assunto , Biblioteca Gênica , Humanos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA Ribossômico/química , RNA Ribossômico/genética , RNA Nucleolar Pequeno/química , RNA Nucleolar Pequeno/genética , Ratos
9.
Am J Physiol Gastrointest Liver Physiol ; 280(6): G1254-60, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11352819

RESUMO

The aims of this study were to elucidate the distribution of angiotensin receptors (AT(1) and AT(2)) in the duodenal wall and to investigate whether AT(2) receptors are involved in the regulation of duodenal mucosal alkaline secretion, which is of importance for the mucosal defense against gastric acid. Immunohistochemistry was used to locate AT(1) and AT(2) receptors in chloralose-anesthetized rats. Duodenal mucosal alkaline output was measured by use of in situ pH-stat titration. Immunohistochemistry demonstrated a distinct staining for both AT(1) and AT(2) receptors in the lamina propria of the villi and also for AT(1) receptors in the muscularis interna. When angiotensin II was infused in the presence of the AT(1) receptor antagonist losartan, mucosal alkaline secretion increased by ~50%. This response was inhibited by the AT(2) receptor antagonist PD-123319. The AT(2) receptor agonist CGP-42112A increased mucosal alkaline secretion by ~50%. This increase was absent in the presence of PD-123319 but not in the presence of losartan or the local anesthetic lidocaine. We conclude that angiotensin II stimulates duodenal mucosal alkaline secretion by activation of AT(2) receptors located in the duodenal mucosa/submucosa.


Assuntos
Bicarbonatos/metabolismo , Duodeno/metabolismo , Mucosa Intestinal/metabolismo , Receptores de Angiotensina/fisiologia , Anestésicos Locais/farmacologia , Angiotensina II/farmacologia , Animais , Duodeno/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Lidocaína/farmacologia , Masculino , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Receptores de Angiotensina/agonistas , Receptores de Angiotensina/metabolismo , Distribuição Tecidual
10.
Bioinformatics ; 16(10): 890-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11120678

RESUMO

MOTIVATION: The choice of probes is an important feature of hybridisation experiments. In this paper we present an algorithm that optimises probes with respect to a training set of sequences based on Shannon entropy as a quality criterion. The practical motivation for our algorithm is oligonucleotide fingerprinting, a method for the simultaneous identification of sequences (cDNA or genomic DNA) by their hybridisation tags according to a set of short probes such as octamers, although the algorithm is of course not restricted to that application. RESULTS: We can show that our method is superior to the selection of probes according to their frequencies, which is a widely used strategy, and to randomly chosen probe sets. The quality of probe sets is assessed by a simulation pipeline that entails the set of probes as a simulation parameter. The performance of probe sets trained on sequences from different organisms shows additionally that probes should be chosen with regard to the organism under analysis. Case studies are presented on how constraints (G+C-content, complexity of the individual probes) influence the selection process. AVAILABILITY: A description of the oligonucleotide fingerprinting pipeline is published on our web-page http://www.molgen.mpg.de/ approximately ag_onf/met.htm. An executable of the algorithm and probe lists designed for human and rodents can be downloaded from the ftp-site ftp://ftp.molgen.mpg.de/pub/mpimg/probe_design/.


Assuntos
Impressões Digitais de DNA/métodos , Sondas de DNA , Hibridização de Ácido Nucleico/métodos , Algoritmos , Animais , Humanos , Oligodesoxirribonucleotídeos/análise , Roedores
11.
Shock ; 14(4): 471-7, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11049112

RESUMO

Angiotensin II (AngII) is an important vasoconstrictor during hypovolemia. This study focused on the effects of the AngII receptor blocker candesartan on intestinal, hepatic, and renal hemodynamics during severe hypovolemia when administered in preexisting moderate hypovolemia. It was hypothesized that specific AngII receptor blockade might enhance splanchnic perfusion during hypovolemia. Fasted, anesthetized, ventilated, juvenile pigs were hemorrhaged by 20% of the blood volume for 30 min. Animals were then randomized to receive candesartan (CAND, n = 11) or the vehicle (CTRL, n = 10) prior to further hemorrhage to 40% of the blood volume for 30 min. The shed blood was then retransfused. Systemic and splanchnic hemodynamics were recorded including intestinal mucosal, superficial and parenchymal hepatic, and cortical and medullary renal microcirculation by laser-Doppler flowmetry. Arterial blood gases were analysed. Candesartan-treated animals maintained mesenteric and jejunal mucosal perfusion during 40% hypovolemia compared to CTRL animals, while no differences were observed in the hepatic and renal circulation. Retransfusion restored mesenteric and renal blood flows despite persistent hypotension and reduced cardiac output in both CAND and CTRL animals. Renal medullary and hepatic parenchymal microcirculation failed to recover during retransfusion in both CAND and CTRL animals. Arterial acidosis, hypercarbia, and a negative base excess were observed in CTRL animals following retransfusion whereas those parameters were normalised in CAND animals. Administration of candesartan in moderate hypovolemia ameliorated the reduction and consequences of mesenteric and intestinal, but not hepatic perfusion during severe hypovolemia. No adverse effects were observed in the renal circulation.


Assuntos
Angiotensina II/antagonistas & inibidores , Benzimidazóis/farmacologia , Hipovolemia/tratamento farmacológico , Hipovolemia/fisiopatologia , Circulação Renal/efeitos dos fármacos , Circulação Esplâncnica/efeitos dos fármacos , Tetrazóis/farmacologia , Equilíbrio Ácido-Base/efeitos dos fármacos , Angiotensina II/fisiologia , Antagonistas de Receptores de Angiotensina , Animais , Compostos de Bifenilo , Feminino , Hemodinâmica/efeitos dos fármacos , Mucosa Intestinal/irrigação sanguínea , Mucosa Intestinal/efeitos dos fármacos , Circulação Hepática/efeitos dos fármacos , Masculino , Microcirculação/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina , Circulação Renal/fisiologia , Circulação Esplâncnica/fisiologia , Suínos
12.
FEBS Lett ; 481(3): 227-34, 2000 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-11007969

RESUMO

Reactive astrocytes occurring in response to neurodegeneration are thought to play an important role in neuronal regeneration by upregulating the expression of extracellular matrix (ECM) components as well as the ECM degrading metalloproteinases (MMPs). We examined the mRNA levels and cellular distribution of membrane type matrix metalloproteinase 1 (MT1-MMP) and tissue inhibitors 1-4 of MMPs (TIMPs) in brain stem and spinal cord of wobbler (WR) mutant mice affected by progressive neurodegeneration and astrogliosis. MT1-MMP, TIMP-1 and TIMP-3 mRNA levels were elevated, whereas TIMP-2 and TIMP-4 expression was not affected. MT1-MMP was expressed in reactive astrocytes of WR. In primary astrocyte cultures, MT1-MMP mRNA was upregulated by exogeneous tumor necrosis factor alpha. Increased plasma membrane and secreted MMP activities were found in primary WR astrocytes.


Assuntos
Astrócitos/enzimologia , Sistema Nervoso Central/enzimologia , Metaloendopeptidases/biossíntese , Doenças Neurodegenerativas/enzimologia , Animais , Astrócitos/imunologia , Astrócitos/patologia , Linhagem Celular , Células Cultivadas , Sistema Nervoso Central/patologia , Indução Enzimática/genética , Indução Enzimática/imunologia , Regulação da Expressão Gênica/imunologia , Metaloproteinase 14 da Matriz , Metaloproteinases da Matriz Associadas à Membrana , Metaloendopeptidases/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes Neurológicos , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , RNA Mensageiro/biossíntese , Proteínas Recombinantes/farmacologia , Inibidor Tecidual de Metaloproteinase-1/biossíntese , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-2/biossíntese , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-3/biossíntese , Inibidor Tecidual de Metaloproteinase-3/genética , Inibidores Teciduais de Metaloproteinases/biossíntese , Inibidores Teciduais de Metaloproteinases/genética , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima/genética , Regulação para Cima/imunologia , Inibidor Tecidual 4 de Metaloproteinase
13.
J Acoust Soc Am ; 108(3 Pt 1): 1181-96, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11008819

RESUMO

Three experimental paradigms were used to specify the auditory system's frequency selectivity for amplitude modulation (AM). In the first experiment, masked-threshold patterns were obtained for signal-modulation frequencies of 4, 16, 64, and 256 Hz in the presence of a half-octave-wide modulation masker, both applied to the same noise carrier with a bandwidth ranging from 1 to 4 kHz. In the second experiment, psychophysical tuning curves (PTCs) were obtained for signal-modulation frequencies of 16 and 64 Hz imposed on a noise carrier as in the first experiment. In the third experiment, masked thresholds for signal-modulation frequencies of 8, 16, 32, and 64 Hz were obtained according to the "classical" band-widening paradigm, where the bandwidth of the modulation masker ranged from 1/8 to 4 octaves, geometrically centered on the signal frequency. The first two experiments allowed a direct derivation of the shape of the modulation filters while the latter paradigm only provided an indirect estimate of the filter bandwidth. Thresholds from the experiments were predicted on the basis of an envelope power-spectrum model (EPSM) which integrates the envelope power of the modulation masker in the passband of a modulation filter tuned to the signal-modulation frequency. The Q-value of second-order bandpass modulation filters was fitted to the masking patterns from the first experiment using a least-squares algorithm. Q-values of about 1 for frequencies up to 64 Hz suggest an even weaker selectivity for modulation than assumed in earlier studies. The same model also accounted reasonably well for the shape of the temporal modulation transfer function (TMTF) obtained for carrier bandwidths in the range from 1 to 6000 Hz. Peripheral filtering and effects of peripheral compression were also investigated using a multi-channel version of the model. Waveform compression did not influence the simulated results. Peripheral bandpass filtering only influenced thresholds for high modulation frequencies when signal information was strongly attenuated by the transfer function of the peripheral filters.


Assuntos
Limiar Auditivo/fisiologia , Adulto , Humanos , Psicofísica
14.
Crit Care Med ; 28(8): 2843-50, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10966260

RESUMO

OBJECTIVE: To examine the effects of hypertonic (7.5%) saline-6% dextran 70 (HSD) and isotonic (0.9%) saline-6% dextran 70 (ISD) on cardiovascular function and intestinal perfusion in experimental endotoxin shock. DESIGN: Experimental, randomized, unblinded, interventional study. SETTING: University experimental animal laboratory. SUBJECTS: Anesthetized and mechanically ventilated landrace pigs (n = 24). INTERVENTIONS: Induction of endotoxin (ET) shock by infusion of Escherichia coil lipopolysaccharide endotoxin (serotype 0111: B4) followed by no fluid treatment (control; C) or small-volume (4 mL/kg) treatment with HSD or ISD. MEASUREMENTS AND MAIN RESULTS: Mean arterial pressure, central venous pressure, pulmonary artery pressure, pulmonary artery occlusion pressure, cardiac output, portal vein blood flow, intestinal microcirculation, intramucosal (regional) P(CO2), intestinal-arterial gap of CO2, and intramucosal pH were monitored, and blood gases were analyzed. Infusion of ET resulted in hypokinetic shock, which in untreated animals led to cardiovascular deterioration and a survival rate of only 33% at 300 mins after start of ET infusion. ISD treatment transiently improved hemodynamic variables and mucosal blood flow but did not affect the survival rate vs. C. Significant beneficial, long-lasting effects of HSD infusion on hemodynamics, especially on mucosal blood flow and intramucosal pH, were demonstrable, resulting in a survival rate of 86%. The relative risk of death at 300 mins was 1.20 for ISD vs. C and 0.17 for HSD vs. C. CONCLUSION: Small-volume HSD resuscitation is much more effective than ISD resuscitation. Variables that were improved include cardiac output, portal blood flow, and intestinal mucosal blood flow in ET shock, all of which improve survival. Such beneficial effects of HSD on splanchnic perfusion may be of value in treating critically ill septic patients in the intensive care unit.


Assuntos
Dextranos/uso terapêutico , Intestinos/irrigação sanguínea , Choque Séptico/tratamento farmacológico , Cloreto de Sódio/uso terapêutico , Animais , Gasometria , Feminino , Soluções Hipertônicas , Soluções Isotônicas , Masculino , Distribuição Aleatória , Fluxo Sanguíneo Regional , Choque Séptico/sangue , Suínos
15.
Genome Res ; 10(8): 1230-40, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10958641

RESUMO

We have used oligonucleotide-fingerprinting data on 60,000 cDNA clones from two different mouse embryonic stages to establish a normalized cDNA clone set. The normalized set of 5,376 clones represents different clusters and therefore, in almost all cases, different genes. The inserts of the cDNA clones were amplified by PCR and spotted on glass slides. The resulting arrays were hybridized with mRNA probes prepared from six different adult mouse tissues. Expression profiles were analyzed by hierarchical clustering techniques. We have chosen radioactive detection because it combines robustness with sensitivity and allows the comparison of multiple normalized experiments. Sensitive detection combined with highly effective clustering algorithms allowed the identification of tissue-specific expression profiles and the detection of genes specifically expressed in the tissues investigated. The obtained results are publicly available (http://www.rzpd.de) and can be used by other researchers as a digital expression reference.


Assuntos
Perfilação da Expressão Gênica/métodos , Biblioteca Gênica , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Algoritmos , Animais , Impressões Digitais de DNA/instrumentação , Impressões Digitais de DNA/métodos , Feto/química , Perfilação da Expressão Gênica/instrumentação , Camundongos , Dados de Sequência Molecular , Família Multigênica , Hibridização de Ácido Nucleico/métodos , Análise de Sequência com Séries de Oligonucleotídeos/instrumentação , Filogenia , Ratos
17.
Genomics ; 66(3): 249-56, 2000 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-10873379

RESUMO

Clustering large data sets is a central challenge in gene expression analysis. The hybridization of synthetic oligonucleotides to arrayed cDNAs yields a fingerprint for each cDNA clone. Cluster analysis of these fingerprints can identify clones corresponding to the same gene. We have developed a novel algorithm for cluster analysis that is based on graph theoretic techniques. Unlike other methods, it does not assume that the clusters are hierarchically structured and does not require prior knowledge on the number of clusters. In tests with simulated libraries the algorithm outperformed the Greedy method and demonstrated high speed and robustness to high error rate. Good solution quality was also obtained in a blind test on real cDNA fingerprints.


Assuntos
Algoritmos , Análise por Conglomerados , Impressões Digitais de DNA/métodos , Simulação por Computador , DNA Complementar/análise , DNA Complementar/genética , Estudos de Avaliação como Assunto , Humanos , Reprodutibilidade dos Testes , Validação de Programas de Computador
18.
Pharmacogenomics ; 1(2): 169-78, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-11256588

RESUMO

The genomics era is providing us with vast amounts of information derived from whole-genome sequencing. This will doubtlessly revolutionise biology and the way novel medicines will be discovered. To leverage this information efficiently, however, technologies in addition to high-throughput sequencing are required. DNA microarray technology is one technology that has already shown great potential for both basic research and drug discovery. With particular emphasis on antibacterial research we will summarise in this review the key technological aspects and most important applications of DNA microarrays demonstrated so far.


Assuntos
Antibacterianos/farmacologia , Bactérias/genética , Análise de Sequência com Séries de Oligonucleotídeos , Farmacogenética/métodos , Bactérias/efeitos dos fármacos , Mapeamento Cromossômico , Análise de Sequência com Séries de Oligonucleotídeos/estatística & dados numéricos , Farmacogenética/estatística & dados numéricos , Farmacogenética/tendências
19.
Genomics ; 59(2): 122-33, 1999 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-10409423

RESUMO

We describe the use of oligonucleotide fingerprinting for the generation of a normalized cDNA library from unfertilized sea urchin eggs and report the preliminary analysis of this library, which resulted in the establishment of a partial gene catalogue of the sea urchin egg. In an analysis of 21,925 cDNA clones by hybridization with 217 oligonucleotide probes, we were able to identify 6291 clusters corresponding to different transcripts, ranging in size from 1 to 265 clones. This corresponds to an average 3.5-fold normalization of the starting library. The normalized library represents about one-third of all genes expressed in the sea urchin egg. To generate sequence information for the transcripts represented by the clusters, representative clones selected from 711 clusters were sequenced. The construction and preliminary analysis of the normalized library are the first steps in the assembly of an increasingly complete collection of maternal genes expressed in the sea urchin egg, which will provide a number of insights into the early development of this well-characterized model organism.


Assuntos
Biblioteca Gênica , Óvulo/metabolismo , Ouriços-do-Mar/genética , Animais , Clonagem Molecular , Impressões Digitais de DNA , DNA Complementar/química , DNA Complementar/classificação , DNA Complementar/genética , Regulação da Expressão Gênica no Desenvolvimento , Dados de Sequência Molecular , Oligonucleotídeos , Óvulo/química , Óvulo/crescimento & desenvolvimento , Ouriços-do-Mar/química , Análise de Sequência de DNA , Transcrição Gênica
20.
Nat Genet ; 22(3): 271-5, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10391215

RESUMO

Arabidopsis thaliana is a small flowering plant that serves as the major model system in plant molecular genetics. The efforts of many scientists have produced genetic maps that provide extensive coverage of the genome (http://genome-www. stanford.edu/Arabidopsis/maps.html). Recently, detailed YAC, BAC, P1 and cosmid-based physical maps (that is, representations of genomic regions as sets of overlapping clones of corresponding libraries) have been established that extend over wide genomic areas ranging from several hundreds of kilobases to entire chromosomes. These maps provide an entry to gain deeper insight into the A. thaliana genome structure. A. thaliana has been chosen as the subject of the first large-scale project intended to determine the full genome sequence of a plant. This sequencing project, together with the increasing interest in map-based gene cloning, has highlighted the requirement for a complete and accurate physical map of this plant species. To supply the scientific community with a high-quality resource, we present here a complete physical map of A. thaliana using essentially the IGF BAC library. The map consists of 27 contigs that cover the entire genome, except for the presumptive centromeric regions, nucleolar organization regions (NOR) and telomeric areas. This is the first reported map of a complex organism based entirely on BAC clones and it represents the most homogeneous and complete physical map established to date for any plant genome. Furthermore, the analysis performed here serves as a model for an efficient physical mapping procedure using BAC clones that can be applied to other complex genomes.


Assuntos
Arabidopsis/genética , Genoma de Planta , Mapeamento Físico do Cromossomo , Cromossomos Bacterianos/genética , Clonagem Molecular , Mapeamento de Sequências Contíguas , Bases de Dados Factuais , Biblioteca Gênica , Marcadores Genéticos
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