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1.
BMC Surg ; 23(1): 303, 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37794384

RESUMEN

PURPOSES: Postoperative bleeding remains a life-threatening complication in thyroid surgery. The aim was to assess the efficacy of four different hemostatic agents, Collagen-Fibrinogen-Thrombin Patch (CFTP) in two sizes (3 × 2.5 cm and 9.5 × 4.8 cm), polysaccharide particles (1 g) and Cellulose Gauze (2.5 × 5 cm) on postoperative drainage volume (DV) compared to a control group. METHODS: We included from October 2007 until Mai 2011, 150 patients (30 per group) for this monocentric, retrospective case-controlled study. Patients were scheduled for a hemithyroidectomy or thyroidectomy. The primary endpoint was the postoperative DV within the first 24 h, secondary the incidence of adverse events. RESULTS: There were no difference in demographic parameters. The mean DV (± SD) was 51.15 (± 36.86) ml in the control, 50.65 (± 42.79) ml in small (3 × 2.5 cm), 25.38 (± 23.99) ml in large CFTP (9.5 × 4.8 cm), 53.11 (± 39.48) ml in the polysaccharide particles and 48.94 (± 30.59) ml in the cellulose gauze group. DV was significantly reduced with the large CFTP (p < 0.05) compared to all other groups. There were no adverse events. CONCLUSIONS: We were able to demonstrate a significant reduction in the DV for the large CFTP group compared to the other collectives. Although this as being associated with not inconsiderable costs and we would only recommend its use for high-risk patients only.


Asunto(s)
Hemostáticos , Glándula Tiroides , Humanos , Glándula Tiroides/cirugía , Estudios Retrospectivos , Hemostáticos/uso terapéutico , Trombina , Fibrinógeno/uso terapéutico , Celulosa/uso terapéutico , Polisacáridos
2.
Circ Res ; 114(2): e2-5, 2014 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-24436435

RESUMEN

RATIONALE: Variants in TRIM63, including a nonsense mutation (p.Q247X), have been suggested recently to cause hypertrophic cardiomyopathy. OBJECTIVE: To verify pathogenicity of TRIM63 p.Q247X detected by whole-exome sequencing in a symptomless professional sports player seeking medical advice because of a prolonged QT interval found during a routine check-up. METHODS AND RESULTS: Clinical studies were performed in the proband and his mother, who also carried TRIM63 p.Q247X. No evidence of hypertrophic cardiomyopathy was found in either person. CONCLUSIONS: The p.Q247X variant in TRIM63 is not likely to be a highly penetrant variant causing hypertrophic cardiomyopathy.


Asunto(s)
Cardiomiopatía Hipertrófica/genética , Cardiomiopatía Hipertrófica/metabolismo , Eliminación de Gen , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Mutación Missense/genética , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Femenino , Humanos , Masculino
3.
Arch Insect Biochem Physiol ; 83(2): 69-85, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23585293

RESUMEN

The secretion of amylase and cellulase in Gryllus bimaculatus is determined by increased food intake, whereby shortly after molting food consumption increases. About half of the standing amylase concentration (activity) in the endothelial cells can be secreted within 30 min. The peak of amylase and cellulase secretion that occurs in the photophase is related to the feeding peak in the previous scotophase. The secretion of chitinase on the other hand is primarily controlled by the molting cycle. Only amylase secretion was affected by calcium in the incubation medium, suggesting an apocrine release mechanism. Refeeding experiments (after 5 days without food) suggest that the release of amylase in response to a nutrient in the lumen (glucose) is not due to simple stimulation of exocytosis, but rather a stimulation of synthesis.


Asunto(s)
Amilasas/metabolismo , Celulasa/metabolismo , Quitinasas/metabolismo , Gryllidae/enzimología , Envejecimiento , Animales , Conducta Alimentaria , Tracto Gastrointestinal/enzimología , Gryllidae/crecimiento & desarrollo , Metamorfosis Biológica , Ninfa/enzimología , Ninfa/crecimiento & desarrollo , Fotoperiodo , Caracteres Sexuales
4.
Front Med Technol ; 5: 1211423, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38045886

RESUMEN

Parylene C is well-known as an encapsulation material for medical implants. Within the approach of miniaturization and automatization of a bone distractor, piezoelectric actuators were encapsulated with Parylene C. The stretchability of the polymer was investigated with respect to the encapsulation functionality of piezoelectric chips. We determined a linear yield strain of 1% of approximately 12-µm-thick Parylene C foil. Parylene C encapsulation withstands the mechanical stress of a minimum of 5×105 duty cycles by continuous actuation. The experiments demonstrate that elongation of the encapsulation on piezoelectric actuators and thus the elongation of Parylene C up to 0.8 mm are feasible.

5.
Int J Integr Care ; 23(1): 17, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37006718

RESUMEN

Introduction: Care integration needs to take place on different levels, including that of infrastructure and especially data infrastructure. Only integrated data allow for policy making, care planning, research, and evaluation that spans across different sectors of care and support. Methods: In the course of an EU-funded reform initiative on integrated care, the Estonian government and various agencies have developed a concept for an integrated data centre, bringing together information from social, medical, and vocational support services. The concept was developed in co-production with many stakeholders. A test data set from all covered sectors, including the pseudonymised data of 17,945 citizens of an Estonian municipality, was created and analysed as a proof-of-concept exercise. Results: The co-production approach resulted in a set of requirements and use cases as well as a specification of premises, processes, and data flows for the data centre. The analysis of the test dataset showed the principal feasibility of the dataset for the intended purposes. Conclusion: The concept development phase showed that an integrated data centre for Estonia is feasible per se and helped to specify concrete actions required for its realisation. Strategic and financial decisions from the Estonian Reform Steering Committee are now needed to create the data centre.

6.
Commun Biol ; 6(1): 1146, 2023 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950046

RESUMEN

Here we present a deep learning-based image analysis platform (DLAP), tailored to autonomously quantify cell numbers, and fluorescence signals within cellular compartments, derived from RNAscope or immunohistochemistry. We utilised DLAP to analyse subtypes of tyrosine hydroxylase (TH)-positive dopaminergic midbrain neurons in mouse and human brain-sections. These neurons modulate complex behaviour, and are differentially affected in Parkinson's and other diseases. DLAP allows the analysis of large cell numbers, and facilitates the identification of small cellular subpopulations. Using DLAP, we identified a small subpopulation of TH-positive neurons (~5%), mainly located in the very lateral Substantia nigra (SN), that was immunofluorescence-negative for the plasmalemmal dopamine transporter (DAT), with ~40% smaller cell bodies. These neurons were negative for aldehyde dehydrogenase 1A1, with a lower co-expression rate for dopamine-D2-autoreceptors, but a ~7-fold higher likelihood of calbindin-d28k co-expression (~70%). These results have important implications, as DAT is crucial for dopamine signalling, and is commonly used as a marker for dopaminergic SN neurons.


Asunto(s)
Aprendizaje Profundo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática , Animales , Humanos , Ratones , Dopamina , Neuronas Dopaminérgicas , Sustancia Negra
7.
JMIR Med Inform ; 8(10): e20938, 2020 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-33021490

RESUMEN

BACKGROUND: Information and communication technology may provide domiciliary care programs with continuity of care. However, evidence about the effectiveness and cost-effectiveness of information and communication technology in the context of integrated care models is relatively scarce. OBJECTIVE: The objective of our study was to provide evidence on the clinical effectiveness and cost-effectiveness of the BeyondSilos project for patients enrolled in the Badalona city pilot site in Spain. METHODS: A quasi-experimental study was used to assess the cost-effectiveness of information and communication technology-enhanced integration of health and social care, including the third sector (intervention), compared to basic health and social care coordination (comparator). The study was conducted in Badalona between 2015 and 2016. Participants were followed for 8 months. RESULTS: The study included 198 patients: 98 in the intervention group and 100 in the comparator group. The mean Barthel index remained unchanged in the intervention group (mean change 0.14, 95% CI -4.51 to 4.78; P=.95) but decreased in the comparator group (mean change -3.23, 95% CI -5.34 to -1.11; P=.003). Instrumental Activities of Daily Living significantly decreased in both groups: mean changes of -0.23 (95% CI -0.44 to -0.02; P=.03) and -0.33 (95% CI -0.46 to -0.20; P<.001) in the intervention and comparator groups, respectively. No differences were found in the Geriatric Depression Scale (intervention: mean change 0.28, 95% CI -0.44 to 1.01, P=.44; comparator: mean change -0.29, 95% CI -0.59 to 0.01, P=.06). The intervention showed cost-effectiveness (incremental cost-effectiveness ratio €6505.52, approximately US $7582). CONCLUSIONS: The information and communication technology-enhanced integrated domiciliary care program was cost-effective. The beneficial effects of this approach strongly rely upon the commitment of the professional staff involved. TRIAL REGISTRATION: ClinicalTrials.gov NCT03111004; http://clinicaltrials.gov/ct2/show/ NCT03111004.

8.
Nat Commun ; 10(1): 5094, 2019 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-31704946

RESUMEN

Degeneration of dopaminergic neurons in the substantia nigra causes the motor symptoms of Parkinson's disease. The mechanisms underlying this age-dependent and region-selective neurodegeneration remain unclear. Here we identify Cav2.3 channels as regulators of nigral neuronal viability. Cav2.3 transcripts were more abundant than other voltage-gated Ca2+ channels in mouse nigral neurons and upregulated during aging. Plasmalemmal Cav2.3 protein was higher than in dopaminergic neurons of the ventral tegmental area, which do not degenerate in Parkinson's disease. Cav2.3 knockout reduced activity-associated nigral somatic Ca2+ signals and Ca2+-dependent after-hyperpolarizations, and afforded full protection from degeneration in vivo in a neurotoxin Parkinson's mouse model. Cav2.3 deficiency upregulated transcripts for NCS-1, a Ca2+-binding protein implicated in neuroprotection. Conversely, NCS-1 knockout exacerbated nigral neurodegeneration and downregulated Cav2.3. Moreover, NCS-1 levels were reduced in a human iPSC-model of familial Parkinson's. Thus, Cav2.3 and NCS-1 may constitute potential therapeutic targets for combatting Ca2+-dependent neurodegeneration in Parkinson's disease.


Asunto(s)
Envejecimiento/genética , Canales de Calcio Tipo R/genética , Proteínas de Transporte de Catión/genética , Supervivencia Celular/genética , Neuronas Dopaminérgicas/metabolismo , Proteínas Sensoras del Calcio Neuronal/genética , Neuropéptidos/genética , Enfermedad de Parkinson/genética , Envejecimiento/metabolismo , Animales , Canales de Calcio Tipo R/metabolismo , Señalización del Calcio , Proteínas de Transporte de Catión/metabolismo , Neuronas Dopaminérgicas/patología , Humanos , Células Madre Pluripotentes Inducidas , Ratones , Ratones Noqueados , Proteínas Sensoras del Calcio Neuronal/metabolismo , Neuropéptidos/metabolismo , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Sustancia Negra/metabolismo , Sustancia Negra/patología , Regulación hacia Arriba , Área Tegmental Ventral/metabolismo , Área Tegmental Ventral/patología
9.
Biochim Biophys Acta ; 1768(10): 2627-34, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17669355

RESUMEN

The twin-arginine-translocase (Tat) can transport proteins in their folded state across bacterial or thylakoid membranes. In Bacillus subtilis the Tat-machinery consists of only two integral (inner) membrane proteins, TatA and TatC. Multiple copies of TatA are supposed to form the transmembrane channel, but little structural data is available on this 70-residue component. We used a multi-construct approach for expressing several characteristic fragments of TatA(d), to determine their individual structures and to cross-validate them comprehensively within the architecture of the full-length protein. Here, we report the design, high-yield expression, detergent-aided purification and lipid-reconstitution of five constructs of TatA(d), overcoming difficulties associated with the very different hydrophobicities and sizes of these membrane protein fragments. Circular dichroism (CD) and oriented CD (OCD) were used to determine their respective conformations and alignments in suitable, negatively charged phospholipid bilayers. CD spectroscopy showed an N-terminal alpha-helix, a central helical stretch, and an unstructured C-terminus, thus proving the existence of these secondary structures in TatA(d) for the first time. The OCD spectra demonstrated a transmembrane orientation of the N-terminal alpha-helix and a surface alignment of the central amphiphilic helix in lipid bilayers, thus supporting the postulated topology model and function of TatA as a transmembrane channel.


Asunto(s)
Bacillus subtilis/enzimología , Membrana Dobles de Lípidos/química , Proteínas de Transporte de Membrana/química , Secuencia de Aminoácidos , Dicroismo Circular , Escherichia coli/genética , Proteínas de Escherichia coli/química , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación
10.
Biochim Biophys Acta ; 1768(12): 3071-9, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17980349

RESUMEN

The transmembrane protein TatA is the pore forming unit of the twin-arginine translocase (Tat), which has the unique ability of transporting folded proteins across the cell membrane. This ATP-independent protein export pathway is a recently discovered alternative to the general secretory (Sec) system of bacteria. To obtain insight in the translocation mechanism, the structure and alignment in the membrane of the well-folded segments 2-45 of TatAd from Bacillus subtilis was studied here. Using solid-state NMR in bicelles containing anionic lipids, the topology and orientation of TatAd was determined in an environment mimicking the bacterial membrane. A wheel-like pattern, characteristic for a tilted transmembrane helix, was observed in 15N chemical shift /15N-1H dipolar coupling correlation NMR spectra. Analysis of this PISA wheel revealed a 14-16 residue long N-terminal membrane-spanning helix which is tilted by 17 degrees with respect to the membrane normal. In addition, comparison of uniformly and selectively 15N-labeled TatA2-45 samples allowed determination of the helix polarity angle.


Asunto(s)
Proteínas Bacterianas/química , Espectroscopía de Resonancia Magnética/métodos , Proteínas de Transporte de Membrana/química , Secuencia de Aminoácidos , Bacillus subtilis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Simulación por Computador , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Datos de Secuencia Molecular
11.
Soft Matter ; 4(6): 1249-1254, 2008 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-32907269

RESUMEN

Embedding biological compounds, e.g. enzymes or whole cells, in solid host material seems to be a promising approach to widen their field of application far beyond the limits of natural conditions. In fields such as medicine and biotechnology, there is great interest in new methods to produce these types of composite materials in the form of micro- or nanosized particles. Such methods should be applicable to large amounts of substance. Inspired by one of nature's remarkable features-its ability to combine (bio)organic and inorganic components at the nanoscale-we developed a generic silica encapsulation method for biomolecules based on the concepts of polyelectrolyte layer adsorption followed by templated silica mineralization similar to biomineralization in diatoms. Application of this method to the model substance purple membrane (PM) resulted in a defined hybrid material with a nanoscale protective encapsulating silica shell providing a high barrier for the diffusion of low molecular weight molecules.

12.
J Phys Chem B ; 111(26): 7519-28, 2007 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-17547443

RESUMEN

Structural investigations on the hydrolysis and condensation behavior of germanium alkoxides were for the first time performed by means of X-ray absorption fine structure and Raman spectroscopy. The studies reveal that germanium alkoxides are monomeric in nature and undergo very fast hydrolysis and condensation reactions upon water addition. However, the chelation of germanium alkoxides by acetylacetone does not take place even 48 h after mixing, and any change in hydrolysis and condensation behavior is not observed after acetylacetone addition. When mixed with prehydrolyzed silicon alkoxide, the structures of germanium alkoxides are not modified. Both Si and Ge precursors are insensitive to the presence of each other in the reaction solution even after 48 h of aging. The addition of water to this mixture catalyzes the hydrolysis and condensation reactions very fast and leads to the formation of Ge-O-Ge (and consequently Si-O-Si) homocondensation products.

13.
J Phys Chem B ; 111(26): 7501-18, 2007 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-17547445

RESUMEN

Structural investigations on the hydrolysis and condensation behavior of hafnium and tantalum alkoxides were for the first time performed by means of X-ray absorption fine structure and Raman spectroscopy. The studies reveal that both of the alkoxides are dimeric in nature and instantaneously undergo hydrolysis and condensation reactions upon the addition of water. The results indicate that the chemical reaction of the alkoxides with acetylacetone occurs immediately with an increase from 6- to 8-fold coordination around the metal. As a consequence of the coordination by a bidentate ligand, hydrolysis and condensation reactions are hindered in solutions of the chemically modified Hf(OnBu)4 and Ta(OEt)5. Furthermore, the investigations demonstrate that the structure of metal alkoxides is not altered after mixing with prehydrolyzed silicon tetraethoxide, and even after 48 h, both of the species remain as separate entities in the mixture. The addition of water to this mixture starts the hydrolysis and condensation reactions instantaneously and leads to the formation of a M-O-M homocondensation product due to the different reactivity of the two alkoxides.

14.
Photochem Photobiol ; 92(3): 488-94, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26946184

RESUMEN

Human skin is exposed to a number of harmful agents of which the ultraviolet (UV) component of solar radiation is most important. UV-induced damages include direct DNA lesions as well as oxidative damage in DNA, proteins and lipids caused by reactive oxygen species (ROS). Being the main site of ROS generation in the cell, mitochondria are particularly affected by photostress. The resulting mitochondrial dysfunction may have negative effects on many essential cellular processes. To counteract these effects, coenzyme Q10 (CoQ10 ) is used as a potent therapeutic in a number of diseases. We analyzed the mitochondrial respiration profile, the mitochondrial membrane potential and cellular ATP level in skin fibroblasts after irradiation. We observed an accelerated regeneration of cellular ATP level, a decrease in mitochondrial dysfunction as well as a preservation of the mitochondrial membrane potential after irradiation in human skin fibroblasts by treatment with CoQ10 . We conclude that the faster regeneration of the ATP level was achieved by a preservation of mitochondrial function by the addition of CoQ10 and that the protective effect of CoQ10 is primarily mediated via its antioxidative function. We suggest also that it might be further dependent on a stimulation of DNA repair enzymes by CoQ10 .


Asunto(s)
Adenosina Trifosfato/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/efectos de la radiación , Piel/citología , Ubiquinona/análogos & derivados , Rayos Ultravioleta , Fibroblastos/metabolismo , Humanos , Estrés Oxidativo , Ubiquinona/farmacología
16.
Dalton Trans ; (7): 946-56, 2008 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-18259629

RESUMEN

The room-temperature stable CI3+ salts [CI3+[pftb](-)1 and [CI3]+[al-f-al](-) 2([pftb](-) = [Al(OC(CF3)3)4](-); [al-f-al](-) = [((CF3)3CO)3Al-F-Al(OC(CF3)3)3](-)) were prepared in quantitative yields from purified CI4 and the corresponding silver aluminates with total exclusion of light (NMR, IR, UV-VIS, X-ray diffraction). The isolated CI(3)(+) cation is trigonal planar with a sum of <(I-C-I) = 360.0 degrees (1) and 359.9 degrees (2). Attempts to prepare CHI2+ and CH2I+ salts from CHI3 or CH2I2/Ag[pftb] mixtures remained unsuccessful; the reaction with CH2I2 leads to the formation of the adduct [Ag(CH2I2)3]+[pftb](-)3, while for HCI3, dismutation with formation of 1 as well as 3 was observed. All particles were also calculated at the MP2/TZVPP level to predict the vibrational and electronic spectra as well as to calculate the Gibbs free energies of all reactions (DeltaG degrees , gas phase and CH2Cl2 solution). Quantum chemical calculations were also used to investigate the stability of the [pftb](-) anion against the electrophilic attack of the CX3+ and CHnX3-n+ cations (X = F-I, n = 1-3). The strength of the Lewis acidity of these cations and of the isoelectronic boron halides BX()and BHnX3-n have been established on the basis of their fluoride ion affinities (FIAs). The FIAs of the carbon and the boron containing compounds show opposite trends, with fluorinated halomethyl cations being stronger acids than their heavier congeners but iodinated holoboranes being stronger acids than their lighter homologues.

17.
J Phys Chem A ; 111(27): 6094-102, 2007 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-17579380

RESUMEN

First-principles gradient-corrected density functional theory electronic structure calculations of the haptotropic rearrangement of a Cr(CO)(3) unit on naphthalene and phenanthrene derivatives are reported. Coupled-cluster calibration studies of Cr(CO)(3) complexes with benzene and naphthalene derivatives confirm the accuracy of the applied Becke exchange and Perdew correlation functionals. Characteristic points on the energy hypersurface (reactants, products, intermediates, and transition states) were located for various substituents on the aromatic skeleton. It is argued that a -OH/-O(-) substituent may provide a means to steer the haptotropic shift depending on the pH value, i.e., to construct a molecular switch. In addition, the mechanism of the [3 + 2 + 1] benzannulation of chromium pentacarbonyl naphthylcarbene complexes with alkynes was investigated, and the preference of the angular benzannulation leading to phenanthrene complexes of Cr(CO)(3) over the linear benzannulation leading to corresponding anthracene complexes is explained.

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