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1.
Phys Rev Lett ; 131(9): 093201, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721828

RESUMO

Light-ion trap (LIONTRAP), a high-precision Penning-trap mass spectrometer, was used to determine the atomic mass of ^{4}He. Here, we report a 12 parts-per-trillion measurement of the mass of a ^{4}He^{2+} ion, m(^{4}He^{2+})=4.001 506 179 651(48) u. From this, the atomic mass of the neutral atom can be determined without loss of precision: m(^{4}He)=4.002 603 254 653(48) u. This result is slightly more precise than the current CODATA18 literature value but deviates by 6.6 standard deviations.

2.
Phys Rev Lett ; 123(17): 173001, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31702246

RESUMO

The recently established agreement between experiment and theory for the g factors of lithiumlike silicon and calcium ions manifests the most stringent test of the many-electron bound-state quantum electrodynamics (QED) effects in the presence of a magnetic field. In this Letter, we present a significant simultaneous improvement of both theoretical g_{th}=2.000 889 894 4 (34) and experimental g_{exp}=2.000 889 888 45 (14) values of the g factor of lithiumlike silicon ^{28}Si^{11+}. The theoretical precision now is limited by the many-electron two-loop contributions of the bound-state QED. The experimental value is accurate enough to test these contributions on a few percent level.

3.
Phys Rev Lett ; 119(3): 033001, 2017 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-28777624

RESUMO

We report on the precise measurement of the atomic mass of a single proton with a purpose-built Penning-trap system. With a precision of 32 parts per trillion our result not only improves on the current CODATA literature value by a factor of 3, but also disagrees with it at a level of about 3 standard deviations.

4.
Chirurgia (Bucur) ; 109(6): 769-73, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25560499

RESUMO

BACKGROUND: As surgeons embrace the concept of increasingly less invasive surgery, techniques using only a single small incision have begun to gain traction. Multiple case series managed by a single-incision laparoscopic cholecystectomy (SILC) have been published. The objective of this study is to describe the short-term outcomes of SILC in our institution. METHODS: A retrospective review was done for 51 patients who underwent SILC between 2009-2012. The operative time, surgical technique, conversion rate, and postoperative complications were reported. RESULTS: SILC was performed for 51 patients, all women, with a mean age of 35.6 years (range=19-62). Their body mass index(BMI) ranged from 16.8-35.6 kg m2 with a mean of 20.4. Twelve patients (23.52 %) had acute cholecystitis. The mean operating time was 58.6 minutes (range=45-95 min). Incidents were encountered in 6 patients (11.76%) and were related to intraoperative bleeding. There was a single conversion to the standard laparoscopic procedure (1.9%) and in 5 cases an accessory needle grasp was used (9.8%). Two patients (3.9%)presented postoperative complications (wound infections) and the mean hospital stay was 1.6 days. CONCLUSIONS: SILC is feasible and provides a promising alternative to natural orifice transluminal endoscopic surgery for scarless laparoscopic cholecystectomy. However, routine application of this novel technique requires an evaluation of its safety and cost effectiveness in larger studies.


Assuntos
Colecistectomia Laparoscópica/métodos , Doenças da Vesícula Biliar/cirurgia , Tempo de Internação , Adulto , Índice de Massa Corporal , Colecistectomia Laparoscópica/instrumentação , Colecistite Aguda/cirurgia , Colecistolitíase/cirurgia , Conversão para Cirurgia Aberta , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Resultado do Tratamento
5.
Chirurgia (Bucur) ; 108(3): 411-3, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23790794

RESUMO

Meckel's diverticulum is a congenital disorder that results from an incomplete obliteration of the vitelline duct. Meckel's diverticulum may give rise to bleeding, intestinal obstruction and inflammation; however, its perforation by a foreign body is an extremely rare life-threatening complication. We report ona 37-year-old male presenting symptoms and signs of acute abdomen with an initial suspicion of acute appendicitis.However, the right diagnosis was made only during exploratory laparoscopy when the appendix was found to be normal,whereas Meckel's diverticulum was found to be inflamed and perforated by a chicken bone. The patient was treated successfully with laparoscopic resection of the diverticulum, and had an uncomplicated postoperative course.


Assuntos
Migração de Corpo Estranho/complicações , Perfuração Intestinal/etiologia , Divertículo Ileal/complicações , Adulto , Migração de Corpo Estranho/diagnóstico , Migração de Corpo Estranho/cirurgia , Humanos , Perfuração Intestinal/diagnóstico , Perfuração Intestinal/cirurgia , Laparoscopia , Masculino , Divertículo Ileal/diagnóstico , Divertículo Ileal/cirurgia , Resultado do Tratamento
6.
Z Geburtshilfe Neonatol ; 216(6): 277-84, 2012 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-23264183

RESUMO

BACKGROUND: A severe hepatopathy constitutes a serious threat during pregnancy and poses considerable challenges to the treating physicians. A broad spectrum of pregnancy-dependent or independent diseases like HELLP-syndrome, liver infection or acute fatty liver of pregnancy (AFLP) is characterized by these affections of the liver. In this study, we present a series of 3 cases with life-threatening hepatopathies and discuss the current state of the literature. A special focus is placed on pathogenesis and differential diagnosis. METHODOLOGY: Pathological, radiological and gynaecological/surgical procedures were performed according to the current German guidelines. Laboratory tests were conducted in the clinics' routine diagnostics section. The existing literature was reviewed via the US National Library of Medicine database "PubMed.gov". RESULTS: The first patient had been afflicted by a fulminant HELLP syndrome causing delivery after 32 weeks of pregnancy. Consecutively, she suffered a sub-total liver infarction followed by a severe coagulopathy and septic peritonitis. The second patient was diagnosed with HELLP syndrome at 36 weeks of pregnancy. The initially mild syndrome exacerbated after delivery leading to haemorrhagic shock and acute renal failure. In the third case, a woman with asymptomatic hepatitis B delivered in the 36th week of pregnancy. Post partum, her pre-existing condition worsened fulminantly resulting in sub-acute liver dystrophy and massive coagulopathy. DISCUSSION AND CONCLUSION: Whenever a hepatopathy occurs during pregnancy, several divergent diagnoses with severe implications and different aetiopathologies have to be considered. Diagnostic and therapeutic strategies have to be weighed quickly to enable a fast, interdisciplinary cooperation in order to prevent fatal outcomes.


Assuntos
Síndrome HELLP/diagnóstico , Falência Hepática/diagnóstico , Transtornos Puerperais/diagnóstico , Adulto , Diagnóstico Diferencial , Progressão da Doença , Feminino , Alemanha , Síndrome HELLP/etiologia , Síndrome HELLP/terapia , Hepatite B Crônica/complicações , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/terapia , Humanos , Recém-Nascido , Infarto/diagnóstico , Infarto/etiologia , Infarto/terapia , Fígado/irrigação sanguínea , Fígado/patologia , Cirrose Hepática/diagnóstico , Cirrose Hepática/etiologia , Cirrose Hepática/terapia , Falência Hepática/etiologia , Falência Hepática/terapia , Testes de Função Hepática , Transplante de Fígado , Gravidez , Transtornos Puerperais/etiologia , Transtornos Puerperais/terapia , Fatores de Risco , Tomografia Computadorizada por Raios X
7.
Clin Transl Radiat Oncol ; 34: 51-56, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35345866

RESUMO

Purpose: To establish stable in vitro growth of keratinocytes from very small biopsy specimens and successfully apply new test systems to determine their radiosensitivity. Materials and Methods: Oral mucosa biopsies (diameter: 1.7 mm) from 15 subjects were immobilized with custom-made cups onto culture plates. Outgrowing cells were tested for cytokeratin 5/14 and Ki67, expanded, radiated at different doses, and seeded onto circumscribed areas before being allowed to spread centrifugally. In this newly developed spreading assay, cell-covered areas were measured by image analysis. For statistical analysis, a linear mixed regression model was used; additionally, results were correlated to the radiation dose applied. Colony forming efficiency (CFE) was used to validate the results. DNA damage repair was analysed by gammaH2AX and 53BP1 foci quantification using immunofluorescence microscopy 24 h and 96 h after irradiation. Results: Stable keratinocyte growth continued for up to 7 weeks in 14 biopsies. Cells spread reliably from an initial 16.6 mm2 up to a median of 119.2 mm2 (range: 54.4-290). Radiated cells spread to only 100.7 mm2 (2 Gy; range: 55.3-266.7); 73.2 mm2 (4 Gy; 15-240.4); 47 mm2 (6 Gy; 2-111.9), and 22.7 mm2 (8 Gy; 0-80). Similarly, CFE decreased from 0.223 (0 Gy) to 0.0028 (8 Gy). Using an individual donor as a random factor, cell spread correlated with CFE, where radiation dose was the main driver (decrease by 0.50, adjusted for area). Upon irradiation with 6 Gy, radiation-induced DNA damage was increased after 24 h in all samples, and even after 96 h in 5 out of 7 samples, as detected by a higher number of gammaH2AX/53BP1 foci in irradiated cells (mean 3.7 for 24 h; mean 0.6 for 96 h). Conclusion: In vitro propagation of keratinocytes derived from a small biopsy is feasible. Radiation impairs cellular migration and proliferation, and the newly described spreading assay allows ranking for cellular radioresistance. The keratinocyte model also supports classical functional assays such as clonogenic survival and DNA double strand repair. The clinical relevance awaits upcoming investigations.

8.
Scand J Public Health ; 39(6 Suppl): 57-61, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21382849

RESUMO

BACKGROUND: Findings on socioeconomic health differentials in youth remain fragmented with the role of cumulative and interaction effects of different forms of health resources not well understood. METHODS: European KIDSCREEN data were analysed to explore effects of material and non-material resources on subjective health in The Netherlands, Hungary, and the UK. RESULTS: Regression analysis revealed significant main effects of economic, social, and cultural resources on youth health. In the UK an interaction effect between economic and cultural resources indicated a conditional relationship between material and non-material health resources. CONCLUSIONS: Exploring the combined impact of economic, social, and cultural resources may contribute to our understanding of health differentials.


Assuntos
Nível de Saúde , Saúde Pública , Fatores Socioeconômicos , Adolescente , Criança , Escolaridade , Feminino , Disparidades nos Níveis de Saúde , Humanos , Hungria , Masculino , Países Baixos , Apoio Social , Inquéritos e Questionários , Reino Unido
9.
J Vet Intern Med ; 24(6): 1452-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21039869

RESUMO

BACKGROUND: Vomiting, nausea, inappetence, and diarrhea are common delayed adverse effects of doxorubicin. Maropitant, a neurokinin-1 receptor antagonist, is known to prevent acute vomiting in dogs receiving cisplatin. OBJECTIVE: To evaluate the efficacy of maropitant in preventing delayed vomiting after administration of doxorubicin to dogs. ANIMALS: Fifty-nine dogs with cancer. METHODS: This randomized, double-blind, placebo-controlled study used a cross-over design. Dogs were randomized into 1 of 2 treatment groups. Group A received maropitant after the 1st doxorubicin, and placebo after the 2nd. Group B received placebo first, and maropitant second. Maropitant (2 mg/kg) or placebo tablets were administered PO for 5 days after doxorubicin treatment. Owners completed visual analog scales based on Veterinary Cooperative Oncology Group-Common Terminology Criteria for Adverse Events to grade their pet's clinical signs during the week after administration of doxorubicin. Statistical differences in gastrointestinal toxicosis and myelosuppression between maropitant and placebo treatments were evaluated. RESULTS: Significantly fewer dogs had vomiting (P=.001) or diarrhea (P=.041), and the severity of vomiting (P<.001) and diarrhea (P=.024) was less the week after doxorubicin when receiving maropitant compared with placebo. No differences were found between maropitant and placebo for other gastrointestinal and bone marrow toxicoses. CONCLUSIONS AND CLINICAL IMPORTANCE: Maropitant is effective in preventing delayed vomiting induced by doxorubicin. Its prophylactic use might improve quality of life and decrease the need for dose reductions in certain dogs.


Assuntos
Antieméticos/uso terapêutico , Antineoplásicos/efeitos adversos , Doenças do Cão/induzido quimicamente , Doxorrubicina/efeitos adversos , Quinuclidinas/uso terapêutico , Vômito/veterinária , Animais , Antineoplásicos/uso terapêutico , Doenças do Cão/prevenção & controle , Cães , Doxorrubicina/uso terapêutico , Feminino , Masculino , Neoplasias/tratamento farmacológico , Vômito/induzido quimicamente , Vômito/prevenção & controle
10.
Eur J Clin Invest ; 38(2): 134-42, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18226047

RESUMO

BACKGROUND: Cholangiocellular carcinomas and gallbladder carcinomas are highly aggressive tumours with a poor prognosis and are generally regarded as chemoresistant tumours. Overexpression of ATP-binding cassette transporters of the multidrug resistance protein (MDR) and multidrug resistance-related protein (MRP) family in cancer cells is a major cause for the multidrug resistance phenotype in vitro and in vivo. To further define the role of MRP family members in biliary tract cancer, we studied the expression and localization of MRP2 and MRP3 in cholangiocellular carcinomas and gallbladder carcinomas. MATERIALS AND METHODS: The expression and cellular localization of the multidrug resistance proteins MRP2 and MRP3 in human cholangiocellular carcinomas and gallbladder carcinomas were analysed by immunohistochemistry using isoform-specific antibodies. Expression of MRP isoforms was studied in vitro in Mz-ChA-1 cells derived from gallbladder adenocarcinoma by reverse transcription-polymerase chain reaction (RT-PCR), immunoblotting and immunofluorescence microscopy. RESULTS: Mz-ChA-1 cells constitutively expressed MDR P-glycoproteins, MRP1, MRP2 and MRP3 by RT-PCR, immunoblotting and immunofluorescence microscopy. MRP2 and MRP3 are expressed in the respective apical and basolateral membrane domains. MRP3 was the predominant MRP isoform in gallbladder carcinomas (93%) and cholangiocellular carcinomas (57%), whereas MRP2 expression was detected in only 29% of gallbladder carcinomas and was undetectable in cholangiocellular carcinomas. CONCLUSIONS: Our findings suggest that the intrinsic multidrug resistance of cholangiocellular and gallbladder carcinomas seems to be independent of MRP2 expression while the expression of MRP3 may contribute to the MDR phenotype.


Assuntos
Colangiocarcinoma/metabolismo , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias da Vesícula Biliar/metabolismo , Proteínas de Membrana Transportadoras/análise , Proteínas Associadas à Resistência a Múltiplos Medicamentos/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Colangiocarcinoma/genética , Neoplasias da Vesícula Biliar/genética , Expressão Gênica , Humanos , Immunoblotting , Proteínas de Membrana Transportadoras/genética , Microscopia de Fluorescência , Pessoa de Meia-Idade , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
11.
Gesundheitswesen ; 70(5): 295-304, 2008 May.
Artigo em Alemão | MEDLINE | ID: mdl-18604768

RESUMO

OBJECTIVES: The incidence distribution of triage advice in the medical call centre Medi24 and the pattern of service utilisation were analysed with respect to two groups of callers with different insurance schemes. Individuals having contracted insurance of the Medi24 model could use the telephone consultation service of the medical call centre Medi24 (mainly part of the mandatory basic health insurance) voluntarily and free of charge whereas individuals holding an insurance policy of the Telmed model (special contract within the mandatory basic health insurance with a premium discount ranging from 8% to 12%) were obliged to have a telephone consultation before arranging an appointment with a medical doctor. METHODS: A cross-sectional study was carried out in the medical call centre Medi24 based on all triage datasets of the Medi24 and Telmed groups collected during the one year period from July 1st 2005 to June 30th 2006. The distribution of the six different urgency levels within the two groups and their respective pattern of service utilisation was determined. In a multivariable logistic regression model the Odds Ratio for every enquiry originating from the Telmed group versus those originating from the Medi24 group was calculated. RESULTS: During a one-year period 48 388 triage requests reached the medical call centre Medi24, 56% derived from the Telmed group and 44% from the Medi24 group. Within the Medi24 group more than 25% of the individuals received self-care advice, within the Telmed group, on the other hand, only about 18% received such advice. In contrast, 27% of the Telmed triage requests but only 18% of the Medi24 triage requests resulted in the advice to make a routine appointment with a medical doctor. The probability that an individual of the Telmed group obtained the advice to go to the accident and emergency department was lower than for an individual of the Medi24 group (OR 0.77, 95% CI 0.60-0.99). Likewise, the probability of self-care advice was decreased in regard to the Medi24 group (OR 0.80, 95% CI 0.75-0.85). However, regarding the advice to make a routine appointment with a medical doctor, the Telmed group was represented more frequently than the Medi24 group (OR 1.36, 95% CI 1.28-1.44). CONCLUSION: In respect of the triage advice, the Telmed group differed significantly from the Medi24 group within all urgency levels. The differences between the two groups in respect of the advice given were still less pronounced than expected against the background of their different contract conditions and the disparate temporal pattern of utilisation. We interprete this finding with the fact that appraising the urgency of health problems appropriately seems to be very difficult for the majority of people seeking advice.


Assuntos
Linhas Diretas/estatística & dados numéricos , Programas Nacionais de Saúde/estatística & dados numéricos , Consulta Remota/estatística & dados numéricos , Triagem/estatística & dados numéricos , Feminino , Humanos , Masculino , Suíça/epidemiologia
12.
AJNR Am J Neuroradiol ; 28(7): 1346-53, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17698539

RESUMO

BACKGROUND AND PURPOSE: Functional MR imaging (fMRI) is rapidly evolving and claims to complement or even substitute intraoperative mapping (IOM) of language functions. However, little is known about the reproducibility of imaging data in the language domain. The aim of our study was to assess the reproducibility of activations for 2 widely used paradigms: naming and word generation. Individual analysis was focused on the Broca area and the left insula. MATERIALS AND METHODS: We examined 13 healthy right-handed subjects in 3 sessions with fMRI. Two conditions were assessed: overt naming and overt naming plus noun generation. The same stimuli were used in all of the sessions. A random-effects analysis was performed to analyze whole-brain activation on a group level. For the regions of interest, the number of voxels classified as active were counted for each subject, and individual reproducibility coefficients were calculated over sessions. RESULTS: For the naming condition, the random-effects analysis did not reveal significant activations in the specified regions; small individual activations were not reproducible. For the combined task, all of the subjects showed activations in the Broca area that were more extensive and reproducible than in the naming task. Activations in the insula were only poorly reproducible. CONCLUSION: Naming is an approved task in IOM but does not identify the Broca area with fMRI in a reproducible way. Priming may have affected our results, but the use of a combined task, in which naming is paired with noun generation, improves the reproducibility of activations and is also suitable for IOM.


Assuntos
Mapeamento Encefálico/métodos , Potenciais Evocados/fisiologia , Lobo Frontal/fisiologia , Idioma , Imageamento por Ressonância Magnética/métodos , Leitura , Análise e Desempenho de Tarefas , Adolescente , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
Vet Comp Oncol ; 15(3): 1019-1028, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27277825

RESUMO

Multi-drug chemotherapy protocols for feline lymphoma have demonstrated variable efficacy and tolerability. In phase I trials, lomustine has demonstrated efficacy for cats with lymphoma though its use for treatment naïve feline intermediate/large cell gastrointestinal (GI) lymphoma remains unknown. This study evaluated the efficacy and tolerability of lomustine for the treatment of feline GI lymphoma. Thirty-two cats with histologically or cytologically confirmed intermediate/large cell GI lymphoma were evaluated retrospectively. Factors assessed included clinical signs, hematologic/biochemical parameters and use of l-asparaginase at induction. A response rate of 50% (16/32), with median duration of response of 302 days (range 64-1450 days), was found. Median progression-free interval was 132 days (range 31-1450 days), with overall median survival time of 108 days (range 4-1488 days). History of hyporexia, presence of anaemia and dose of lomustine were significantly associated with progression-free survival. Overall, lomustine is a well-tolerated and effective treatment for feline GI lymphoma.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Doenças do Gato/tratamento farmacológico , Neoplasias Gastrointestinais/veterinária , Lomustina/uso terapêutico , Linfoma/veterinária , Animais , Gatos , Feminino , Neoplasias Gastrointestinais/tratamento farmacológico , Linfoma/tratamento farmacológico , Masculino , Estudos Retrospectivos , Resultado do Tratamento
14.
Dalton Trans ; 46(30): 9760-9764, 2017 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-28708189

RESUMO

The synthesis, crystallographic analysis and full characterization of the Cu(i) complex-functionalized Anderson polyoxomolybdate anions (nBu4N)[MMo6O18((OCH2)3CNCH(C47H37N2P2OCu)2)] (M = Mn3+, Fe3+, Co3+) is reported. For the first time, direct crystallographic evidence for the covalent attachment of a photoactive metal complex to an organo-functionalized polyoxometalate is obtained. Initial electrochemical and photochemical studies report fundamental properties and solution stability of the compounds.

16.
Vet Comp Oncol ; 15(4): 1564-1571, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28419683

RESUMO

BACKGROUND: In humans geographical differences in the incidence and presentation of various cancers have been reported. However, much of this information has not been collected in veterinary oncology. AIM: The purpose of this study was to determine if a geographic difference in progression free survival exists for dogs with lymphoma treated within the US. MATERIALS AND METHODS: Medical records of 775 cases of canine lymphoma from 3 US regions (west, south and north), treated with CHOP chemotherapy, were retrospectively evaluated. Cases were collected from referral institutions and were required to have received at least one doxorubicin treatment and have follow up information regarding time to progression. RESULTS: Significant differences in sex (p = 0.05), weight (p = 0.049), stage (p < 0.001), immunophenotype (p = <0.001), and number of doxorubicin doses (p = 0.001) were seen between regions. Upon univariate analysis, progression free survival (PFS) differed by region (p = 0.006), stage (p = 0.009), sub-stage (p = 0.0005), and immunophenotype (p = 0.001). A multivariable Cox regression model showed that dogs in the western region had a significantly shorter PFS when compared to the south and east. CONCLUSION: PFS was significantly affected by stage, sub-stage and phenotype.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doenças do Cão/tratamento farmacológico , Linfoma não Hodgkin/veterinária , Animais , Ciclofosfamida/uso terapêutico , Doenças do Cão/mortalidade , Cães , Doxorrubicina/uso terapêutico , Feminino , Geografia Médica , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/mortalidade , Masculino , Prednisona/uso terapêutico , Estudos Retrospectivos , Análise de Sobrevida , Estados Unidos/epidemiologia , Vincristina/uso terapêutico
17.
J Neuroendocrinol ; 18(2): 97-103, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16420278

RESUMO

Activins are members of the transforming growth factor-beta superfamily that exert neurotrophic and neuroprotective effects on various neuronal populations. To determine the possible function of activin in stroke injury, we assessed which components of the activin signalling pathway were modulated in response to middle cerebral artery occlusion (MCAO). Furthermore, because oestradiol replacement protects against MCAO-induced cell death, we explored whether oestradiol replacement influences activin gene expression. Female Sprague-Dawley rats underwent permanent MCAO and the expression of activins and their corresponding receptors was determined by semiquantitative reverse transcriptase-polymerase chain reaction at 24 h after onset of ischaemia. We observed up-regulation of activin betaA and activin type I receptor A mRNA in response to injury. Dual-label immunocytochemistry followed by confocal z-stack analysis showed that the activin A expressing cells comprised neurones. Next, we monitored the time course of activin betaA mRNA expression in oestradiol- or vehicle-treated rats at 4, 8, 16 and 24 h after MCAO via in situ hybridisation. Starting at 4 h after injury, activin betaA mRNA was up-regulated in cortical and striatal areas in the ipsilateral hemisphere. Activin betaA mRNA levels in the cortex increased dramatically with time and were highest at 24 h after the insult, and oestradiol replacement did not influence this increase.


Assuntos
Receptores de Ativinas Tipo I/metabolismo , Estradiol/fisiologia , Regulação da Expressão Gênica , Infarto da Artéria Cerebral Média/metabolismo , Subunidades beta de Inibinas/genética , Neurônios/metabolismo , Receptores de Ativinas Tipo I/genética , Análise de Variância , Animais , Dano Encefálico Crônico/genética , Dano Encefálico Crônico/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Estradiol/administração & dosagem , Feminino , Regulação da Expressão Gênica/fisiologia , Infarto da Artéria Cerebral Média/genética , Subunidades beta de Inibinas/metabolismo , Neostriado/metabolismo , Neostriado/patologia , Neurônios/patologia , RNA Mensageiro/análise , Ratos , Transdução de Sinais/fisiologia , Distribuição Tecidual
18.
Dalton Trans ; 45(1): 74-7, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26610813

RESUMO

A cationic iridium complex with a 2,2'-bibenzimidazole ligand can act as a luminescent sensor for various anions. Strong H-bond supported ion pair bonding with an electron accepting dinitro-benzoate anion switches the luminescence "off". The luminescence of the sensor is switched back "on" when benzoate is replaced by competing H-bonded small anions, therefore leading to an enhanced sensitivity of the sensor system.

19.
Dalton Trans ; 45(41): 16121-16124, 2016 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-27711825

RESUMO

The covalent functionalization of metal oxide surfaces with organic ligands gives unique organic-inorganic hybrids. Here we report a bifunctional organic tether combining a phosphonate for metal oxide anchoring with an organic azide for attachment of organic groups. Stable binding of the tether to molecular and solid-state metal oxides is demonstrated and the subsequent "CLICKability" of the TiO2-anchored tether is shown. The phosphonate-azide reported could in future allow the general linkage of functional organic groups to metal oxides.

20.
Dalton Trans ; 44(19): 8889-905, 2015 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-25871461

RESUMO

The synthesis of tpphz(tbp)2 (tpphz(tbp)2 = 3,16-di(tert-butyl-phenyl)-tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2''',3'''-j]phenazine) has been optimized by using a new synthetic route. The complexes Ru(tbp)2tpphz, Rutpphz(tbp)2, Rutpphz(tbp)2Ru and the reference compound Ru(tbp)2phen (where Ru = (tbbpy)2Ru, tbbpy = 4,4'-di-tert-butyl-2,2'-bipyridine and (tbp)2phen = 3,8-bis(4-tert-butyl-phenyl)-1,10-phenanthroline) have been synthesized and characterized. Crystal structures or structural motifs could be obtained for each intermediate and complex and for the first time a tpphz based uncomplexed ligand could be investigated in the solid state. The mononuclear complexes Ru(tbp)2tpphz and Rutpphz(tbp)2 form π­π stacked dimers in the solid state. The latter exhibits an interesting aggregation in the solid state with three π-interactions. Concentration dependent aggregation of these isomers in solution is observed with the aid of 1H-NMR investigations. Out of those dimerization constants (KD) could be calculated for the complexes Ru(tbp)2tpphz and Rutpphz(tbp)2. The values differ significantly. Photophysical and electrochemical properties of the presented complexes were investigated and compared with reference compounds. The tert-butyl-phenyl-substitution induces a stabilization of the 1MLCT and 3MLCT states localized on the phenanthroline part of the bridging ligand. The 3MLCT localized on the phenazine portion seems to be not or only to a minor extent influenced by these substituents.

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