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1.
Inorg Chem ; 63(1): 129-140, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38109782

RESUMO

Three new coordination polymers (CPs) constructed from the linker 1,4-di(dithiocarboxylate) (BDDTC2-)─the sulfur-analog of 1,4-benzenedicarboxylate (BDC2-)─together with Mn-, Zn-, and Fe-based inorganic SBUs are reported with description of their structural and electronic properties. Single-crystal X-ray diffraction revealed structural diversity ranging from one-dimensional chains in [Mn(BDDTC)(DMF)2] (1) to two-dimensional (2D) honeycomb sheets observed for [Zn2(BDDTC)3][Zn(DMF)5(H2O)] (2). Gas adsorption experiments confirmed a 3D porous structure for the mixed-valent material [Fe2(BDDTC)2(OH)] (3). 3 contains a 1:1 ratio of Fe2+/3+ ions, as evidenced by 57Fe Mössbauer, X-band EPR, and X-ray absorption spectroscopy. Its empirical formula was established by elemental analysis, thermal gravimetric analysis, infrared vibrational spectroscopy, and X-ray absorption spectroscopy in lieu of elusive single-crystal X-ray diffraction data. In contrast to the Mn- and Zn-based compounds 1 and 2, the Fe2+/3+ CP 3 showed remarkably high electrical conductivity of 5 × 10-3 S cm-1 (according to van der Pauw measurements), which is within the range of semiconducting materials. Overall, our study confirms that sulfur derivatives of typical carboxylate linkers (e.g., BDC) are suitable for the construction of electrically conducting CPs, due to acceptedly higher covalency in metal-ligand bonding compared to the electrically insulating carboxylate CPs or metal-organic frameworks. At the same time, the direct comparison between insulating CPs 1 and 2 with CP 3 emphasizes that the electronic structure of the metal is likewise a crucial aspect to construct electrically conductive materials.

2.
J Interv Cardiol ; 31(6): 916-924, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30397932

RESUMO

AIMS: To evaluate the impact of right ventricular dysfunction (RVD) on outcome after transcatheter mitral valve repair (TMVR) in patients with chronic heart failure (CHF) and severe functional mitral regurgitation (FMR). METHODS AND RESULTS: One hundred thirty patients (median age 72.7 ± 10.7 years; 63.8% male) at high operative risk (LogEuroSCORE 23.8 ± 13.9%) with FMR and CHF (left ventricular ejection fraction 32 ± 7%) were enrolled and separated into two groups according to the RVD. RVD was assessed by the tricuspid annular plane systolic excursion (TAPSE) method (A: TAPSE ≤ 16 mm, n = 58; B: TAPSE > 16 mm, n = 72). The rate of successful reduction of mitral regurgitation (MR ≤2+) by TMVR was similar in both groups (94.6% vs 91.2%; P: n.s.) with low in-hospital major adverse event rates. During a median follow-up period of 10.5 ± 4 months, the Kaplan-Meier analysis revealed a significantly higher all-cause mortality in group A (43.1% vs 23.6%; log-rank P = 0.039) and a significantly higher rate of hospital readmission due to congestive heart failure (56.9% vs 26.4%; log-rank P < 0.001). At long-term follow-up, 25% of patients in group A remained in NYHA functional class IV (none in group B). Preexisting RVD as assessed by TAPSE and Doppler tissue imaging (DTI-S') was an independent predictor of all-cause mortality after TMVR (hazard ratio 2.84; 95% confidence interval 1.15-7.65; P = 0.039; hazard ratio 4.70; 95% confidence interval 1.14-20.21; P = 0.044, respectively). CONCLUSIONS: Patients with CHF and RVD were with regard to functional capacity less often responder and showed an unfavorable long-term outcome. Thus, patients with CHF and RVD seem to benefit less frequently from TMVR.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Insuficiência Cardíaca/cirurgia , Insuficiência da Valva Mitral/cirurgia , Disfunção Ventricular Direita/complicações , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos Cardíacos/métodos , Doença Crônica , Ecocardiografia , Feminino , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/mortalidade , Hemodinâmica , Mortalidade Hospitalar , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/mortalidade , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Resultado do Tratamento , Função Ventricular Esquerda
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 6311-6314, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28269692

RESUMO

This work presents the design and testing of an integrated 8-channel CMOS biopotential recording chip, consisting of low-noise input stages, tunable second stage, a multiplexer, and two analog-to-digital converters (ADC). Through its variable supply concept, the integrated input-referred noise of the first stage is selectable from 1.5 down to 0.63 µVRMS (ISS = 200 µA), which is superior to standard laboratory recording systems. The device features variable lower and upper corner frequencies, and outputs two digital 16-bit data streams at 62.5 kS/s. The chip die was fabricated in X-Fab 0.35 µm CMOS technology and has an area of 10 mm2.


Assuntos
Conversão Análogo-Digital , Metais/química , Óxidos , Semicondutores , Razão Sinal-Ruído , Desenho de Equipamento
4.
BMC Med Educ ; 12: 101, 2012 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-23107588

RESUMO

BACKGROUND: Focused emergency echocardiography performed by non-cardiologists has been shown to be feasible and effective in emergency situations. During resuscitation a short focused emergency echocardiography has been shown to narrow down potential differential diagnoses and to improve patient survival. Quite a large proportion of physicians are eligible to learn focused emergency echocardiography. Training in focused emergency echocardiography usually comprises a lecture, hands-on trainings in very small groups, and a practice phase. There is a shortage of experienced echocardiographers who can supervise the second step, the hands-on training. We thus investigated whether student tutors can perform the hands-on training for focused emergency echocardiography. METHODS: A total of 30 volunteer 4th and 5th year students were randomly assigned to a twelve-hour basic echocardiography course comprising a lecture followed by a hands-on training in small groups taught either by an expert cardiographer (EC) or by a student tutor (ST). Using a pre-post-design, the students were evaluated by an OSCE. The students had to generate two still frames with the apical five-chamber view and the parasternal long axis in five minutes and to correctly mark twelve anatomical cardiac structures. Two blinded expert cardiographers rated the students' performance using a standardized checklist. Students could achieve a maximum of 25 points. RESULTS: Both groups showed significant improvement after the training (p < .0001). In the group taught by EC the average increased from 2.3±3.4 to 17.1±3.0 points, and in the group taught by ST from 2.7±3.0 to 13.9±2.7 points. The difference in improvement between the groups was also significant (p = .03). CONCLUSIONS: Hands-on training by student tutors led to a significant gain in echocardiography skills, although inferior to teaching by an expert cardiographer.


Assuntos
Ecocardiografia , Educação Médica , Medicina de Emergência/educação , Mentores , Grupo Associado , Estudantes de Medicina , Adulto , Competência Clínica , Currículo , Avaliação Educacional , Feminino , Alemanha , Humanos , Masculino , Mentores/educação , Avaliação de Programas e Projetos de Saúde , Método Simples-Cego , Adulto Jovem
5.
Int J Med Microbiol ; 294(7): 465-70, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15715175

RESUMO

Micromonas (Peptostreptococcus) micros is frequently associated with periodontal disease as well as respiratory, gastrointestinal and female genitourinary tract infections, but only rarely has been reported as a pathogenic agent of prosthetic joint infections. Here we describe a case of a 63-year-old woman with prosthetic joint infection of total hip arthroplasty caused by the anaerobic species Micromonas micros, associated with tooth extraction. Samples obtained intraoperatively and from the oral cavity were positive for the presence of M. micros by culture and by real-time PCR. This case report indicates that infections of prosthetic joints can be associated with dental procedures and that sensitive molecular techniques are necessary for their routine diagnostic.


Assuntos
Prótese de Quadril/microbiologia , Artropatias/microbiologia , Peptostreptococcus/isolamento & purificação , Infecções Relacionadas à Prótese/microbiologia , Extração Dentária/efeitos adversos , Idoso , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos
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