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1.
Nature ; 623(7989): 932-937, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38030780

RESUMO

Planets with radii between that of the Earth and Neptune (hereafter referred to as 'sub-Neptunes') are found in close-in orbits around more than half of all Sun-like stars1,2. However, their composition, formation and evolution remain poorly understood3. The study of multiplanetary systems offers an opportunity to investigate the outcomes of planet formation and evolution while controlling for initial conditions and environment. Those in resonance (with their orbital periods related by a ratio of small integers) are particularly valuable because they imply a system architecture practically unchanged since its birth. Here we present the observations of six transiting planets around the bright nearby star HD 110067. We find that the planets follow a chain of resonant orbits. A dynamical study of the innermost planet triplet allowed the prediction and later confirmation of the orbits of the rest of the planets in the system. The six planets are found to be sub-Neptunes with radii ranging from 1.94R⊕ to 2.85R⊕. Three of the planets have measured masses, yielding low bulk densities that suggest the presence of large hydrogen-dominated atmospheres.

2.
Psychiatr Q ; 92(2): 419-430, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32789719

RESUMO

Psychiatrists play an important role in providing access to psychiatric electrical interventions (PEIs) such as electroconvulsive therapy (ECT) and transcranial magnetic stimulation (TMS). As such, their views on these procedures likely influence whether they refer or provide these types of treatments for their clinically depressed patients. Despite this, scholars have too infrequently examined psychiatrists' views about specific PEIs and have not yet examined their views across different PEIs. To gain insight into psychiatrists' views about PEIs, we conducted a qualitative study based on semi-structured interviews with 16 psychiatrists in Michigan. The majority of psychiatrists had a positive attitude towards PEIs in general. One-third reported cautionary attitudes towards PEIs; they did not reject the interventions but were skeptical of their effectiveness or felt they needed further development. The majority of psychiatrists consider ECT and TMS to be viable therapies that they would discuss with their patients after several failed medication trials. There was a lack of knowledge about surgical PEIs, such as deep brain stimulation. This study provides insights into how psychiatrists perceive PEIs. While broadly positive attitudes exist, this research highlights certain challenges, particularly lack of knowledge and ambiguity about the use of PEIs.


Assuntos
Atitude do Pessoal de Saúde , Eletroconvulsoterapia/normas , Psiquiatria , Pesquisa Qualitativa , Estimulação Magnética Transcraniana/normas , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
J Intern Med ; 287(5): 534-545, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31976601

RESUMO

BACKGROUND: Fibroblast growth factor 19 (FGF19) is produced in the small intestine and is involved in suppression of hepatic bile acid (BA) synthesis. FGF19 is also expressed in the liver and serum levels are elevated in adults with cholestatic liver disease. This may reflect a rescue mechanism to dampen liver injury caused by increased intrahepatic BAs. OBJECTIVES: To examine circulating FGF19 at early stages of biliary atresia and at short-term follow-up post-Kasai portoenterostomy (KPE) in relation to noncholestatic infants. The relationship between FGF19, BAs and markers for BA synthesis and hepatic gene expression of factors involved in BA metabolism were also evaluated. METHODS: Liver tissue, portal and peripheral blood samples were obtained from fifteen patients at KPE; additional blood was collected 4-6 months after surgery. Two control groups were included; to examine possible changes related to surgery and to compare FGF19 in biliary atresia to noncholestatic infants. RESULTS: Circulating FGF19 levels correlated to its hepatic gene expression at time of KPE in biliary atresia and levels were elevated compared to noncholestatic infants. At follow-up, FGF19 levels were markedly reduced, and the decline coincided with reductions in bilirubin and conjugated chenodeoxycholic acid and with increased levels of the BA synthesis marker C4. CONCLUSION: Elevated circulating FGF19 in biliary atresia is of hepatic origin and reduced following KPE. Changes in serum FGF19 may reflect the level of restoration of the enterohepatic circulation, and this warrants further long-term studies on the role of FGF19 in the cholestatic liver.


Assuntos
Ácidos e Sais Biliares/metabolismo , Atresia Biliar/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Portoenterostomia Hepática , Ácidos e Sais Biliares/sangue , Atresia Biliar/cirurgia , Feminino , Humanos , Lactente , Fígado/metabolismo , Masculino , Portoenterostomia Hepática/efeitos adversos , Reação em Cadeia da Polimerase em Tempo Real , Resultado do Tratamento
4.
Am J Transplant ; 16(3): 1021-30, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26523372

RESUMO

Clinical hepatocyte transplantation is hampered by low engraftment rates and gradual loss of function resulting in incomplete correction of the underlying disease. Preconditioning with partial hepatectomy improves engraftment in animal studies. Our aim was to study safety and efficacy of partial hepatectomy preconditioning in clinical hepatocyte transplantation. Two patients with Crigler-Najjar syndrome type I underwent liver resection followed by hepatocyte transplantation. A transient increase of hepatocyte growth factor was seen, suggesting that this procedure provides a regenerative stimulus. Serum bilirubin was decreased by 50%, and presence of bilirubin glucuronides in bile confirmed graft function in both cases; however, graft function was lost due to discontinuation of immunosuppressive therapy in one patient. In the other patient, serum bilirubin gradually increased to pretransplant concentrations after ≈600 days. In both cases, loss of graft function was temporally associated with emergence of human leukocyte antigen donor-specific antibodies (DSAs). In conclusion, partial hepatectomy in combination with hepatocyte transplantation was safe and induced a robust release of hepatocyte growth factor, but its efficacy on hepatocyte engraftment needs to be evaluated with additional studies. To our knowledge, this study provides the first description of de novo DSAs after hepatocyte transplantation associated with graft loss.


Assuntos
Formação de Anticorpos/imunologia , Síndrome de Crigler-Najjar/imunologia , Rejeição de Enxerto/etiologia , Antígenos HLA/imunologia , Hepatectomia/efeitos adversos , Hepatócitos/transplante , Transplante de Fígado/efeitos adversos , Doadores de Tecidos , Adolescente , Adulto , Criança , Síndrome de Crigler-Najjar/cirurgia , Feminino , Humanos , Lactente , Masculino , Complicações Pós-Operatórias , Prognóstico
5.
Rev Med Suisse ; 11(463): 505-10, 2015 Feb 25.
Artigo em Francês | MEDLINE | ID: mdl-25898459

RESUMO

Sudden death is the first cause of mortality in patients with end stage renal disease undergoing chronic dialysis treatment. The technique of dialysis as well as the chemical composition of the dialysate can impact on the incidence of cardiac arrhythmias. Pilot studies reveal that the use of an acetate-free dialysate with a downstream filter infusion of sodium bicarbonate, coupled with a modulated potassium-profiled dialysate during hemodialysis, or acetate free biofiltration with potassium profiled dialysate, reduces the incidence of arrhythmias, the QT interval and QT dispersion. The limitation of the ultrafiltration volume during the dialysis session, and the increase in calcium concentration in the dialysate are other possible strategies to reduce cardiac arrhythmias.


Assuntos
Arritmias Cardíacas/prevenção & controle , Diálise Renal/métodos , Humanos
6.
J Physiol Pharmacol ; 75(3)2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39042386

RESUMO

Suicide is a significant public health challenge worldwide. Statistical data confirm a strong relationship between suicidal behavior and depressive disorders (DDs), but the molecular mechanisms of these diseases are still poorly understood. A growing body of research suggests that the Klotho-mediated pathway may be a novel intracellular target for the development of suicide-related disorders (including DDs). To verify this hypothesis, the link between α-Klotho levels, Nrf2-related inflammatory status (IL-1α, IL-1ß, Keap1, NFκB p65), AMPA (GluA1, GluA2, p-S831-GluA1, p-S845-GluA1) receptor subunit trafficking and AMPK (AMPKα1/2; pT172-AMPKα1) signalling pathways in the brain of suicide victims as compared to controls were investigated. Commercially available enzyme-linked immunoassay (ELISA) and Western blot analysis were performed in the hippocampus (HP) and frontal cortex (FCx) of suicide victims and matched controls. Group differences were assessed using an unpaired Student's t-test. A statistically significant decrease in the level of α-Klotho (HP: p=0.001; FCx: p=0.012) with an increase in IL-1ß (HP: p=0.0108) and IL-1α (FCx: p=0.009) concentrations were shown. These alterations were associated with increased Keap1 (FCx: p=0.023) and NF-κB-p65 (HP: p=0.039; FCx: p=0.013 nuclear fraction) protein levels. Furthermore, a significant reduction in p-S831-GluA1 (HP: p=0.029; FCx=0.002) and p-S845-GluA1 (HP: p=0.0012) proteins was observed. Similarly, the level of GluA2 (HP: p=0.011; FCx: p=0.002) and in p-T172-AMPKα1 (HP: p=0.0288; FCx: p=0.0338) protein were statistically decreased. Our findings demonstrate that a reduction in α-Klotho levels in brain structures related to mood disorders (HP, FCx) correlates with suicidal behavior. Moreover, our study provides novel insights into the molecular mechanisms underlying suicide-related disorders, highlighting the role of α-Klotho, Nrf2-related inflammatory status, AMPA receptor trafficking, and AMPK signaling pathways in the pathophysiology of suicidal behavior. These results may have implications for the development of targeted interventions for individuals at risk of suicide.


Assuntos
Glucuronidase , Proteína 1 Associada a ECH Semelhante a Kelch , Proteínas Klotho , Fator 2 Relacionado a NF-E2 , Receptores de AMPA , Transdução de Sinais , Suicídio , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Encéfalo/metabolismo , Lobo Frontal/metabolismo , Glucuronidase/metabolismo , Hipocampo/metabolismo , Interleucina-1beta/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Transporte Proteico , Receptores de AMPA/metabolismo , Suicídio/psicologia
7.
J Physiol Pharmacol ; 74(3)2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37661185

RESUMO

Suicide is a global public health concern. There is evidence of an association between suicidal behavior and depressive disorders (DDs). An increasing number of studies have suggested that nuclear factor erythroid-derived 2-like 2 (Nrf2), a major endogenous regulator of the oxidative stress response, can be a novel target for the neurobiology of suicide-related disorders (including depression). This study aimed to investigate the relationship between oxidative stress progression, Nrf2 regulation, and N-methyl-D-aspartate receptor (NMDA) subunit composition in the hippocampus (Hp) and frontal cortex (FCx) of suicide victims (n=14) and matched controls (n=8). Furthermore, zinc and magnesium concentrations and their potency to inhibit [3H] MK-801 (radioactively labeled form of MK-801 - dizocilpine, a well-characterized NMDAR channel uncompetitive antagonist frequently used in receptor-binding assays) binding to NMDA receptor channels were measured. Our results revealed a statistically significant increase in protein carbonyl levels and thiobarbituric acid-reactive substances (TBARS) concentrations in Hp and FCx of suicide victims. Enhanced superoxide dismutase (SOD) activity (only in FCx) in suicides compared to controls was shown. These alterations were accompanied by an increase in Nrf2 protein levels in whole homogeneous tissue lysates and cytosolic fractions of Hp and FCx. Importantly, suicide victims presented a significant reduction in Nrf2 protein levels in the nuclear fraction of FCx. Finally, the observed decrease in N-methyl-D-aspartate receptor subunit 2B (GluN2B) and postsynaptic density proteins 95 (PSD-95) protein levels was associated with a statistically significant reduction in magnesium levels in the FCx of suicide victims. These results confirm for the first time that increased oxidative stress parameters are related to Nrf2 protein changes and alterations in the NMDA receptor complex in the pathophysiology of suicidal behavior.


Assuntos
Fator 2 Relacionado a NF-E2 , Suicídio , Humanos , Receptores de N-Metil-D-Aspartato , Maleato de Dizocilpina , Magnésio , Encéfalo , Estresse Oxidativo
8.
J Intern Med ; 272(3): 201-23, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22789058

RESUMO

Inherited metabolic diseases of the liver are characterized by deficiency of a hepatic enzyme or protein often resulting in life-threatening disease. The remaining liver function is usually normal. For most patients, treatment consists of supportive therapy, and the only curative option is liver transplantation. Hepatocyte transplantation is a promising therapy for patients with inherited metabolic liver diseases, which offers a less invasive and fully reversible approach. Procedure-related complications are rare. Here, we review the experience of hepatocyte transplantation for metabolic liver diseases and discuss the major obstacles that need to be overcome to establish hepatocyte transplantation as a reliable treatment option in the clinic.


Assuntos
Transplante de Células/métodos , Hepatócitos/citologia , Hepatopatias/terapia , Erros Inatos do Metabolismo/terapia , Imunidade Adaptativa , Animais , Técnicas de Cultura de Células , Senescência Celular , Criopreservação , Humanos , Imunidade Inata , Terapia de Imunossupressão , Doadores de Tecidos , Condicionamento Pré-Transplante
9.
Opt Express ; 20(13): 14508-13, 2012 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-22714512

RESUMO

We present a method of fabricating Ge-doped SiO2 fibers with corrugations around their full circumference for a desired length in the longitudinal direction. The procedure comprises three steps: hydrogenation of Ge-doped SiO2 fibers to increase photosensitivity, recording of Bragg gratings with ultraviolet light to achieve modulation of refractive index, and chemical etching. Finite-length, radially corrugated fibers may be used as couplers. Corrugated tapered fibers are used as high energy throughput probes in scanning near-field optical microscopy.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Germânio/química , Refratometria/instrumentação , Dióxido de Silício/química , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
10.
J Clin Virol ; 135: 104694, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33476928

RESUMO

In resource-limited settings, use of dried blood spots (DBS) could be a pragmatic alternative to plasma for VL monitoring in people living with HIV (PLWH). We compared results from DBS to standard plasma VL testing under field conditions in patients receiving antiretroviral therapy (ART). DBS cards were prepared from venous blood (V-DBS), finger-pricks using micro-capillary tubes (M-DBS), and direct spotting (D-DBS). DBS and matched EDTA plasma were tested on the Abbott m2000 platform using the appropriate RealTime HIV-1 quantitative CE protocol. Matched plasma samples were also tested on the Roche COBAS Ampliprep/COBAS TaqMan version 2.0. Diagnostic accuracy indicators (sensitivity, specificity, misclassification rate, and kappa coefficient) for viral failure (VF) based on different VL threshold levels and agreement of absolute VL were calculated. A total of 669 participants provided 2676 samples. V-DBS had a peak sensitivity for VF of 89.1 % [95 % CI: 85.5-92.7] at the 1000 copies/mL threshold and a peak specificity of 97.4 % [95 % CI: 95.9-99.0] at the 5000 copies/mL threshold. The lowest proportion of upward misclassification (patients classified with VF who actually had viral suppression) for V-DBS was 3.1 % [95 % CI: 1.4-4.8] at the 5000 copies/mL threshold, whereas the lowest proportion of downward misclassification (patients classified as undetectable who actually had VF) was 10.9 % [95 % CI: 7.2-14.5] at the 1000 copies/mL threshold. Abbott RealTime HIV-1 VL results from all 3 DBS types for adults and children showed strong correlation with the gold standard plasma-based assay. DBS could be useful for monitoring VL in resource limited settings such as Nigeria.


Assuntos
Infecções por HIV , HIV-1 , Adulto , Criança , Teste em Amostras de Sangue Seco , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Nigéria , RNA Viral , Sensibilidade e Especificidade , Manejo de Espécimes , Carga Viral
11.
Science ; 290(5490): 337-41, 2000 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-11030652

RESUMO

A nuclear isoform of myosin I beta that contains a unique 16-amino acid amino-terminal extension has been identified. An affinity-purified antibody to the 16-amino acid peptide demonstrated nuclear staining. Confocal and electron microscopy revealed that nuclear myosin I beta colocalized with RNA polymerase II in an alpha-amanitin- and actinomycin D-sensitive manner. The antibody coimmunoprecipitated RNA polymerase II and blocked in vitro RNA synthesis. This isoform of myosin I beta appears to be in a complex with RNA polymerase II and may affect transcription.


Assuntos
Núcleo Celular/metabolismo , Proteínas Motores Moleculares , Miosinas/metabolismo , RNA Polimerase II/metabolismo , RNA/biossíntese , Transcrição Gênica , Células 3T3 , Actinas/metabolismo , Amanitinas/farmacologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Dactinomicina/farmacologia , Éxons , Células HeLa , Humanos , Camundongos , Microscopia Confocal , Microscopia Eletrônica , Dados de Sequência Molecular , Miosinas/química , Miosinas/genética , Miosinas/imunologia , Inibidores da Síntese de Ácido Nucleico/farmacologia , Testes de Precipitina , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , Isoformas de Proteínas/metabolismo
12.
Klin Padiatr ; 221(3): 174-5, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19437367

RESUMO

We report on a 15-year-old girl referred to us for dyspnea. Investigations revealed multiple pulmonary emboli originating from iliac vein thrombosis. As under heparin therapy, d-dimers rose again and the thrombus grew significantly in size while platelet count decreased by >30%. A diagnosis of heparin-induced thrombocytopenia (HIT) type II was suspected, heparin-treatment was stopped and lepirudin therapy was started successfully at a doses of 0.15 mg/kg bw/hr.


Assuntos
Anticoagulantes/efeitos adversos , Fibrinolíticos/uso terapêutico , Heparina/efeitos adversos , Veia Ilíaca , Embolia Pulmonar/tratamento farmacológico , Trombocitopenia/induzido quimicamente , Trombose/tratamento farmacológico , Adolescente , Anticoagulantes/uso terapêutico , Diagnóstico Diferencial , Relação Dose-Resposta a Droga , Feminino , Heparina/uso terapêutico , Hirudinas , Humanos , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Embolia Pulmonar/diagnóstico , Proteínas Recombinantes/uso terapêutico , Recidiva , Trombose/diagnóstico , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler , Veia Cava Inferior
13.
Hamostaseologie ; 29(3): 256-9, 2009 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-19644604

RESUMO

In contrast to heparins and oral anticoagulants, anti IIa inhibitors (thrombin inhibitors) are able to directly inhibit the protease activity of thrombin and can thereby precisely control the blood coagulation process. Direct thrombin inhibitors are either biosimilars (r-hirudin) or synthetically produced substances (bivalirudin, argatroban, dabigatran). In 1997 r-hirudin was introduced into clinical practice, however due to its narrow therapeutic range and the necessity of drug monitoring it has not gained widespread clinical use by now. Since 2004 and 2005 the synthetic thrombin inhibitors bivalirudin and argatroban, respectively, are available. With dabigatran the first oral synthetic thrombin inhibitor followed in 2008. These four drugs can inhibit even clot bound thrombin and show low plasma protein binding. They differ in respect to route and duration of application as well as elimination from the body, thereby offering a precise inhibition of blood coagulation adjusted to the individual case and without danger of HIT II. These advantages shall be used and advanced by the development of further direct thrombin inhibitors.


Assuntos
Anticoagulantes/uso terapêutico , Hemostasia/efeitos dos fármacos , Heparina/uso terapêutico , Vitamina K/antagonistas & inibidores , Varfarina , Idoso , Anticoagulantes/farmacocinética , Biotransformação , Cumarínicos/farmacocinética , Cumarínicos/uso terapêutico , Feminino , Hemostasia/genética , Heparina/efeitos adversos , Heparina/farmacocinética , Humanos , Coeficiente Internacional Normatizado , Masculino , Pessoa de Meia-Idade , Farmacogenética , Insuficiência Renal/induzido quimicamente , Varfarina/farmacocinética , Varfarina/uso terapêutico
14.
Transplant Proc ; 51(3): 845-851, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30979474

RESUMO

BACKGROUND: Despite an increase in the number of pancreas transplants in the Scandiatransplant region in the last decade, there continues to be a gap between demand and supply of transplantable organs. This imbalance has encouraged the transplant community to consider new sources of grafts, such as the reintroduction of donors after circulatory death (DCD) who were the standard donors in our center before 1988. MATERIAL AND METHODS: In this long-term follow-up study, we compare 44 consecutive, simultaneous pancreas kidney transplants performed at Karolinska University Hospital between 1986 and 1991: 21 patients received DCD grafts and 23 received grafts from donors after brain death. RESULTS: Both groups had similar donor and recipient characteristics, but cold ischemia times were significantly shorter in the DCD group. Warm ischemia times were very short compared with other studies on DCDs. Patient and graft survival rates were similar in both groups. CONCLUSION: This study suggests that controlled DCD pancreas and kidney grafts transplanted simultaneously can be a feasible option for reducing organ shortage without any negative impact on the long-term results.


Assuntos
Transplante de Rim/métodos , Transplante de Pâncreas/métodos , Doadores de Tecidos , Adulto , Morte Encefálica , Isquemia Fria , Morte , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Transplante de Rim/mortalidade , Masculino , Pessoa de Meia-Idade , Transplante de Pâncreas/mortalidade , Taxa de Sobrevida , Doadores de Tecidos/provisão & distribuição , Transplantes/provisão & distribuição , Isquemia Quente
15.
Surg Endosc ; 22(4): 938-42, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17705079

RESUMO

BACKGROUND: Laparoscopic donor nephrectomy has become the first choice for living donor kidney transplantation, offering advantages over open donor nephrectomy. This study aimed to evaluate kidney tissue metabolism during and after pneumoperitoneum using a microdialysis technique. METHODS: Eight pigs underwent laparotomy and implantation of two microdialysis catheters: one in the cortex and one in the medulla of the left kidney. After laparotomy, the abdominal wall was closed, and pneumoperitoneum was induced with a constant standard pressure of 16 to 18 mmHg for 4 h, followed by rapid desufflation. In microdialysis samples collected from intrarenal catheters, markers of ischemia (glucose, lactate, pyruvate, and lactate-pyruvate ratio) and the marker of cell membrane injury (glycerol) were monitored. RESULTS: There were no changes in glucose, lactate, or pyruvate level before, during, or after pneumoperitoneum, either in the cortex or in the medulla. Additionally, the calculated lactate-pyruvate ratio did not show signs of ischemia during or after pneumoperitoneum. However, with regard to the marker of cell injury, glycerol increased in the medulla after decompression from 22.57 +/- 3.76 to 35.67 +/- 5.43 mmol/l (p < 0.01). This release of glycerol in the medulla was significantly higher than in the cortex (area under the curve [AUC], 22.18 +/- 4.87 vs 34.79 +/- 7.88 mmol/l; p < 0.01). CONCLUSIONS: The pattern of metabolic changes monitored in the kidney during and after pneumoperitoneum indicates some kind of cell injury predominant in the medulla without any signs of kidney ischemia. This nonischemic injury could be related to hyperperfusion of the kidney after decompression or injury to cells attributable to mechanical cell expansion at the point of rapid decompression.


Assuntos
Rim/metabolismo , Laparoscopia , Microdiálise , Nefrectomia/métodos , Pneumoperitônio Artificial , Animais , Área Sob a Curva , Glucose/metabolismo , Glicerol/metabolismo , Ácido Láctico/metabolismo , Ácido Pirúvico/metabolismo , Estatísticas não Paramétricas , Suínos
17.
Neuropharmacology ; 53(6): 741-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17870136

RESUMO

The purpose of the present study was to investigate whether the anxiolytic-like action of a selective and brain penetrable group I metabotropic glutamate (mGlu5) receptor antagonist 3-[(2-methyl-1,3-tiazol-4-yl)ethynyl]-pyridine (MTEP) is dependent upon the serotonergic system. Experiments were performed on male Wistar rats. The Vogel conflict drinking test was used to detect anxiolytic-like activity. MTEP administered intraperitoneally at doses of 1, 3 and 6 mg/kg induced anxiolytic-like effect. The potential anxiolytic effect of MTEP (1 mg/kg) was inhibited by a nonselective 5-HT receptor antagonist metergoline (2 mg/kg i.p.) and 5-HT2A/2C receptor antagonist ritanserin (0.5 mg/kg i.p.), but not by a 5-HT1A receptor antagonist N-{2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl}-N-(2-pyridynyl)cyclohexane-carboxamide (WAY 100635) (0.1 mg/kg i.p). The anxiolytic effect of MTEP (6 mg/kg) was attenuated by ritanserin (1 mg/kg i.p.). Moreover, MTEP-induced a dose-dependent release of serotonin in the frontal cortex. The obtained results suggest that the potential anxiolytic effect of the mGlu5 receptor antagonist MTEP is due to the increased serotonin release with subsequent activation of 5-HT2A/2C receptors, most probably located postsynaptically, but not by the 5-HT1A receptors.


Assuntos
Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Piridinas/farmacologia , Serotonina/metabolismo , Tiazóis/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Injeções Intraperitoneais , Masculino , Metergolina/farmacologia , Microdiálise , Piperazinas/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Wistar , Receptor de Glutamato Metabotrópico 5 , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Ritanserina/farmacologia , Antagonistas da Serotonina/farmacologia
18.
Mol Biol Cell ; 9(9): 2509-25, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9725909

RESUMO

To explore the role of nonmuscle myosin II isoforms during mouse gametogenesis, fertilization, and early development, localization and microinjection studies were performed using monospecific antibodies to myosin IIA and IIB isotypes. Each myosin II antibody recognizes a 205-kDa protein in oocytes, but not mature sperm. Myosin IIA and IIB demonstrate differential expression during meiotic maturation and following fertilization: only the IIA isoform detects metaphase spindles or accumulates in the mitotic cleavage furrow. In the unfertilized oocyte, both myosin isoforms are polarized in the cortex directly overlying the metaphase-arrested second meiotic spindle. Cortical polarization is altered after spindle disassembly with Colcemid: the scattered meiotic chromosomes initiate myosin IIA and microfilament assemble in the vicinity of each chromosome mass. During sperm incorporation, both myosin II isotypes concentrate in the second polar body cleavage furrow and the sperm incorporation cone. In functional experiments, the microinjection of myosin IIA antibody disrupts meiotic maturation to metaphase II arrest, probably through depletion of spindle-associated myosin IIA protein and antibody binding to chromosome surfaces. Conversely, the microinjection of myosin IIB antibody blocks microfilament-directed chromosome scattering in Colcemid-treated mature oocytes, suggesting a role in mediating chromosome-cortical actomyosin interactions. Neither myosin II antibody, alone or coinjected, blocks second polar body formation, in vitro fertilization, or cytokinesis. Finally, microinjection of a nonphosphorylatable 20-kDa regulatory myosin light chain specifically blocks sperm incorporation cone disassembly and impedes cell cycle progression, suggesting that interference with myosin II phosphorylation influences fertilization. Thus, conventional myosins break cortical symmetry in oocytes by participating in eccentric meiotic spindle positioning, sperm incorporation cone dynamics, and cytokinesis. Although murine sperm do not express myosin II, different myosin II isotypes may have distinct roles during early embryonic development.


Assuntos
Fertilização/fisiologia , Meiose/fisiologia , Mitose/fisiologia , Miosinas/metabolismo , Animais , Afinidade de Anticorpos , Células COS , Divisão Celular , Demecolcina/farmacologia , Desenvolvimento Embrionário e Fetal , Feminino , Regulação da Expressão Gênica , Isoenzimas/metabolismo , Masculino , Camundongos , Microinjeções , Cadeias Pesadas de Miosina/metabolismo , Cadeias Leves de Miosina/metabolismo , Miosinas/genética , Oócitos , Fosforilação , Isoformas de Proteínas , Interações Espermatozoide-Óvulo , Espermatozoides/metabolismo , Espermatozoides/fisiologia
19.
Hamostaseologie ; 27(2): 105-10, 2007 May.
Artigo em Alemão | MEDLINE | ID: mdl-17479173

RESUMO

The central enzyme of blood coagulation, the serine proteinase thrombin, is capable to modify the growth of tumour cells by interaction with protease activated receptors 1 and 4 of the tumour cells. Thrombin is permanently available in tumour micro environment; meizothrombin is generated from prothrombin at a tumour specific activation complex and can influence tumour cell growth via PAR-1 and 7-transdomain protein receptor signalling pathway, too. PEG-coupled direct thrombin inhibitors that possess special pharmacokinetic characteristics and that have been designed for long lasting efficacy in extracellular space, control serine proteinase activity in tumour micro environment and therefore they own a high potential anti-tumour efficacy. In xenographic tumour models this new substance class has shown a significant carcinostatic effect.


Assuntos
Divisão Celular/efeitos dos fármacos , Neoplasias/patologia , Receptores de Trombina/fisiologia , Trombina/efeitos adversos , Sequência de Aminoácidos , Hirudinas/farmacologia , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica , Receptor PAR-1/fisiologia , Receptores de Trombina/química , Transdução de Sinais
20.
Vitam Horm ; 103: 295-326, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28061974

RESUMO

Elements (bioelements) are necessary factors required for the physiological function of organisms. They are critically involved in fundamental processes of life. Extra- and intracellular message and metabolic pathway factors as well as structural components include one or many elements in their functional structure. Recent years have seen an intensification in terms of knowledge gained about the roles of elements in anxiety disorders. In this chapter we present a review of the most important current data concerning the involvement of zinc, magnesium, copper, lithium, iron, and manganese, and their deficiency, in the pathophysiology and treatment of anxiety.


Assuntos
Transtornos de Ansiedade/etiologia , Ansiedade/etiologia , Deficiências Nutricionais/fisiopatologia , Modelos Animais de Doenças , Oligoelementos/deficiência , Animais , Ansiedade/prevenção & controle , Transtornos de Ansiedade/prevenção & controle , Deficiências Nutricionais/dietoterapia , Deficiências Nutricionais/psicologia , Suplementos Nutricionais , Humanos , Magnésio/uso terapêutico , Deficiência de Magnésio/dietoterapia , Deficiência de Magnésio/fisiopatologia , Deficiência de Magnésio/psicologia , Oligoelementos/uso terapêutico , Zinco/deficiência , Zinco/uso terapêutico
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