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1.
Medicina (Kaunas) ; 60(4)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38674213

RESUMO

Background and Objectives: There are many surgical techniques for oroantral communication treatment, one of which is the buccal fat pad. Of particular interest is the high reparative potential of the buccal fat pad, which may be contributed to by the presence of mesenchymal stem cells. The purpose of this work is to evaluate the reparative potential of BFP cells using morphological and immunohistochemical examination. Materials and Methods: 30 BFP samples were provided by the Clinic of Maxillofacial and Plastic Surgery of the Russian University of Medicine (Moscow, Russia) from 28 patients. Morphological examination of 30 BFP samples was performed at the Institute of Clinical Morphology and Digital Pathology of Sechenov University. Hematoxylin-eosin, Masson trichrome staining and immunohistochemical examination were performed to detect MSCs using primary antibodies CD133, CD44 and CD10. Results: During staining with hematoxylin-eosin and Masson's trichrome, we detected adipocytes of white adipose tissue united into lobules separated by connective tissue layers, a large number of vessels of different calibers, as well as the general capsule of BFP. The thin connective tissue layers contained neurovascular bundles. Statistical processing of the results of the IHC examination of the samples using the Mann-Whitney criterion revealed that the total number of samples in which the expression of CD44, CD10 and CD133 antigens was confirmed was statistically significantly higher than the number of samples where the expression was not detected (p < 0.05). Conclusions: During the morphological study of the BFP samples, we revealed statistically significant signs of MSCs presence (p < 0.05), including in the brown fat tissue, which proves the high reparative potential of this type of tissue and can make the BFP a choice option among other autogenous donor materials when eliminating OAC and other surgical interventions in the maxillofacial region.


Assuntos
Tecido Adiposo , Compostos Azo , Bochecha , Imuno-Histoquímica , Humanos , Imuno-Histoquímica/métodos , Feminino , Masculino , Antígeno AC133/análise , Receptores de Hialuronatos/análise , Neprilisina/análise , Células-Tronco Mesenquimais , Adulto , Amarelo de Eosina-(YS) , Hematoxilina , Verde de Metila
2.
Int J Mol Sci ; 24(8)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37108443

RESUMO

The causes of heart valve bioprosthetic calcification are still not clear. In this paper, we compared the calcification in the porcine aorta (Ao) and the bovine jugular vein (Ve) walls, as well as the bovine pericardium (Pe). Biomaterials were crosslinked with glutaraldehyde (GA) and diepoxide (DE), after which they were implanted subcutaneously in young rats for 10, 20, and 30 days. Collagen, elastin, and fibrillin were visualized in non-implanted samples. Atomic absorption spectroscopy, histological methods, scanning electron microscopy, and Fourier-transform infrared spectroscopy were used to study the dynamics of calcification. By the 30th day, calcium accumulated most intensively in the collagen fibers of the GA-Pe. In elastin-rich materials, calcium deposits were associated with elastin fibers and localized differences in the walls of Ao and Ve. The DE-Pe did not calcify at all for 30 days. Alkaline phosphatase does not affect calcification since it was not found in the implant tissue. Fibrillin surrounds elastin fibers in the Ao and Ve, but its involvement in calcification is questionable. In the subcutaneous space of young rats, which are used to model the implants' calcification, the content of phosphorus was five times higher than in aging animals. We hypothesize that the centers of calcium phosphate nucleation are the positively charged nitrogen of the pyridinium rings, which is the main one in fresh elastin and appears in collagen as a result of GA preservation. Nucleation can be significantly accelerated at high concentrations of phosphorus in biological fluids. The hypothesis needs further experimental confirmation.


Assuntos
Bioprótese , Calcinose , Doenças das Valvas Cardíacas , Próteses Valvulares Cardíacas , Ratos , Animais , Bovinos , Suínos , Elastina , Cálcio , Bioprótese/efeitos adversos , Próteses Valvulares Cardíacas/efeitos adversos , Calcinose/patologia , Glutaral , Colágeno , Fósforo , Pericárdio/patologia
3.
Int J Mol Sci ; 24(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37446270

RESUMO

Carbon nanotubes (CNTs) are used in applications ranging from electrical engineering to medical device manufacturing. It is well known that the addition of nanotubes can influence the mechanical properties of various industrial materials, including plastics. Electrospinning is a popular method for fabricating nanomaterials, widely suggested for polymer scaffold manufacturing. In this study, we aimed to describe the influence of single-walled carbon nanotube (SWCNT) suspensions on polymeric poured films and electrospun scaffolds and to investigate their structural and mechanical properties obtained from various compositions. To obtain films and electrospun scaffolds of 8 mm diameter, we used poly-ε-caprolactone (PCL) and poly(cyclohexene carbonate) (PCHC) solutions containing several mass fractions of SWCNT. The samples were characterized using tensile tests, atomic force and scanning electronic microscopy (AFM and SEM). All the studied SWCNT concentrations were shown to decrease the extensibility and strength of electrospun scaffolds, so SWCNT use was considered unsuitable for this technique. The 0.01% mass fraction of SWCNT in PCL films increased the polymer strength, while fractions of 0.03% and more significantly decreased the polymer strength and extensibility compared to the undoped polymer. The PHCH polymeric films showed a similar behavior with an extremum at 0.02% concentration for strength at break.


Assuntos
Nanotubos de Carbono , Nanotubos de Carbono/química , Engenharia Tecidual/métodos , Poliésteres/química , Suspensões , Polímeros , Alicerces Teciduais/química
4.
Anal Chem ; 91(6): 3778-3783, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30773009

RESUMO

We propose monitoring of diabetes through continuous analysis of undiluted sweat immediately after its excretion using a flow-through glucose biosensor. The used biosensors are based on Prussian Blue and glucose oxidase immobilized in perfluorosulfonated ionomer or gel of alkoxysilane; the resulting sensitivity with the latter reaches in batch mode 0.23 A M-1 cm-2, and the calibration range is from 1 µM to 1 mM (flow-through mode). On the basis of the glucose tolerance test known to be a clinically relevant procedure to mimic hyperglycemia, a positive correlation between the rates of glucose concentration increase in blood and in noninvasively collected sweat has been observed ( r = 0.75). The observed correlation between sweat and blood considering low-molecular weight metabolites is even better than that observed previously between capillary and vein blood, confirming diagnostic value of sweat for diabetes monitoring. The dynamics of sweat glucose concentration, recorded by means of the proposed biosensor, is in a good accordance with the dynamics of blood glucose content without any time delay, thus offering a prospect for noninvasive monitoring of diabetes.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus/metabolismo , Glucose/metabolismo , Monitorização Fisiológica/métodos , Suor/metabolismo , Adulto , Feminino , Voluntários Saudáveis , Humanos , Masculino , Siloxanas/química , Fatores de Tempo , Adulto Jovem
5.
Anal Chem ; 89(21): 11198-11202, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29065687

RESUMO

For noninvasive diagnostics of hypoxia, we propose the nonenzymatic sensor based on screen-printed structures with the working surface modified in course of electropolymerization of 3-aminophenylboronic acid (3-APBA) with imprinting of lactate. Impedimetric sensor allows lactate detection in the range from 3 mM to 100 mM with the detection limit of 1.5 mM; response time is 2-3 min. Sensor sensitivity remains unchanged within 6 months of storage unpacked in dry state at a room temperature, which is unachievable for enzyme based devices. Analysis of human sweat with poly(3-APBA) based sensor is possible due to (i) much higher lactate content compared to other polyols and (ii) high sensor selectivity (Klactateglucose < 3 × 10-2). Successful detection of lactate in human sweat by means of the poly(3-APBA) based sensor has been confirmed using the highly specific reference method based on lactate oxidase enzyme (correlation coefficient r > 0.9). The attractive performance characteristics of poly(3-APBA) based enzyme-free sensors justify their future use for noninvasive clinical analysis and sports medicine.


Assuntos
Técnicas Eletroquímicas/métodos , Ácido Láctico/análise , Suor/química , Ácidos Borônicos/química , Humanos , Limite de Detecção , Polimerização , Polímeros/química
6.
Chemphyschem ; 18(18): 2482-2486, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28726353

RESUMO

The copper salt of trifluoroacetic acid, Cu(CF3 COO)2 , offers a new platform to investigate the quantum ground states of low-dimensional magnets. In practice, it realizes the ideal case of a solid hosting essentially isolated magnetic monolayers. These entities are constituted by well-separated two-leg half-integer spin ladders organized in a zigzag fashion. The ladders are comprised of dimeric units of edge-sharing tetragonal pyramids coupled through carbon ions. The spin-gap state in this compound was revealed by static and dynamic magnetic measurements. No indications of long range magnetic ordering down to liquid helium temperature were obtained in specific heat measurements. First principles calculations allow estimation of the main exchange interaction parameters, J⊥ =176 K and J∥ =12 K, consistent with the weakly interacting dimers model.

7.
J Xenobiot ; 14(3): 989-1002, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39189170

RESUMO

Microplastics (MPs) in aquatic environments can be associated with various substances, including persistent organic pollutants, which add to the problem of plastic ecotoxicity. The abundance of 1-5 mm microplastics and concentrations of particle-adsorbed organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in sandy sediments from three beaches in recreational areas along the upper Ob River in Western Siberia were assessed. MP pollution levels in the Ob River beach sands ranged from 24 ± 20.7 to 104 ± 46.2 items m-2 or, in terms of mass concentration, from 0.26 ± 0.21 to 1.22 ± 0.39 mg m-2. The average abundance of MP particles reached 0.67 ± 0.58 items kg-1 or 8.22 ± 6.13 µg kg-1 in the studied sediments. MP concentrations were significantly higher in number (p < 0.05) and mass (p < 0.01) at the riverbank site downstream of the Novosibirsk wastewater treatment plant (WWTP) outfall compared to these at the upstream and more distant beaches. Most MPs (70-100%) were represented by irregularly shaped fragments. The polymer composition of MPs varied between sites, with a general predominance of polyethylene (PE). The study revealed associations of MPs with PCBs and OCPs not previously detected in the riverbed and beach sediments, suggesting that these substances are circulating in the Ob River basin. Although MP concentrations were higher downstream of the WWTP, the maximum levels of particle-associated OCPs were observed in the beach sands of the site farthest from the urban agglomeration. The pesticides γ-HCH, 4,4-DDT, and 4,4-DDE were detected on MPs at relatively low concentrations. PCBs were more abundant in the studied samples, including 118 dioxin-like congener. The results obtained indicate that the Ob River is susceptible to plastic and persistent organic pollutant (POP) contamination and serve as a starting point for further studies and practical solutions to the problem.

8.
Polymers (Basel) ; 14(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35054754

RESUMO

Electrospinning is a perspective method widely suggested for use in bioengineering applications, but the variability in currently available data and equipment necessitates additional research to ascertain the desirable methodology. In this study, we aimed to describe the effects of electrospinning technique alterations on the structural and mechanical properties of (1,7)-polyoxepan-2-one (poly-ε-caprolactone, PCL) scaffolds, such as circumferential and longitudinal stress/strain curves, in comparison with corresponding properties of fresh rat aorta samples. Scaffolds manufactured under different electrospinning modes were analyzed and evaluated using scanning electronic microscopy as well as uniaxial longitudinal and circumferential tensile tests. Fiber diameter was shown to be the most crucial characteristic of the scaffold, correlating with its mechanical properties.

9.
J Biomed Mater Res A ; 110(2): 394-408, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34390309

RESUMO

The aim of this study was to compare the mechanical properties and thermal stability of the venous wall depending on the treatment method used, and, accordingly, on those structural changes in the tissue that this treatment causes. Bovine jugular vein walls (BJVWs) cross-linked with glutaraldehyde (GA), ethylene glycol diglycidyl ether (DE), and Contegra commercial conduit were evaluated using uniaxial stretching [with and without pre-conditioning (PreC)], differential scanning calorimetry, amino acid analysis, and attenuated total reflection infrared spectroscopy. Fresh BJVW was used as a control. It was shown that failure stress in non-PreC GA-treated and DE-treated materials was lower than that in fresh and Contegra counterparts. Contegra samples were the stiffest among the tested materials. Cyclic preloading leads to distortion of the mechanical behavior of this material, which is heterogeneous in composition and structure. The denaturation temperatures (Td ) of all cross-linked BJVWs were higher than the Td of the fresh vein. The microstructures of the tested BJVWs did not exhibit any differences, but the cross-linking density and hydration of the DE-vein were the highest. GA-cross-linking or DE-cross-linking and isopropanol exposure (Contegra) changed the protein secondary structures of the tested materials in different ways. We hypothesized that the protein secondary structure and hydration degree are the main causes of differences in the mechanical properties and thermal stability of BJVW.


Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Animais , Bovinos , Glutaral , Veias Jugulares , Temperatura
10.
Plast Reconstr Surg Glob Open ; 10(3): e4166, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35291331

RESUMO

Iatrogenic glossopharyngeal nerve injuries are commonly associated with procedures such as a tonsillectomy, carotid endarterectomy, and endotracheal intubation. We present a previously unreported complication of a thread lift procedure in the jowl region, causing damage to the glossopharyngeal nerve through compression. The glossopharyngeal nerve belongs to the bulbar group of the cranial nerves. It is connected with the vagus and, therefore, is closely associated with the latter functionally and anatomically. Damage to the former may present with cardiovascular complications associated with the vagus nerve. The presented case demonstrates the diagnostic and treatment aspects of iatrogenic injury to the glossopharyngeal nerve.

11.
Polymers (Basel) ; 14(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36015570

RESUMO

Electrospun tissue-engineered grafts made of biodegradable materials have become a perspective search field in terms of vascular replacement, and more research is required to describe their in vivo transformation. This study aimed to give a detailed observation of hemodynamic and structural properties of electrospun, monolayered poly-ε-caprolactone (PCL) grafts in an in vivo experiment using a rat aorta replacement model at 10, 30, 60 and 90 implantation days. It was shown using ultrasound diagnostic and X-ray tomography that PCL grafts maintain patency throughout the entire follow-up period, without stenosis or thrombosis. Vascular compliance, assessed by the resistance index (RI), remains at the stable level from the 10th to the 90th day. A histological study using hematoxylin-eosin (H&E), von Kossa and Russell-Movat pentachrome staining demonstrated the dynamics of tissue response to the implant. By the 10th day, an endothelial monolayer was forming on the graft luminal surface, followed by the gradual growth and compaction of the neointima up to the 90th day. The intense inflammatory cellular reaction observed on the 10th day in the thickness of the scaffold was changed by the fibroblast and myofibroblast penetration by the 30th day. The cellularity maximum was reached on the 60th day, but by the 90th day the cellularity significantly (p = 0.02) decreased. From the 60th day, in some samples, the calcium phosphate depositions were revealed at the scaffold-neointima interface. Scanning electron microscopy showed that the scaffolds retained their fibrillar structure up to the 90th day. Thus, we have shown that the advantages of PCL scaffolds are excellent endothelialization and good surgical outcome. The disadvantages include their slow biodegradation, ineffective cellularization, and risks for mineralization and intimal hyperplasia.

12.
Methods Mol Biol ; 2198: 401-428, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32822047

RESUMO

CRISPR/cas9 is a popular tool, widely used today for genome editing. However, the modular organization of this tool allows it to be used not only for DNA modifications but also for introducing epigenetic modifications both in DNA (methylation/demethylation) and in histones (acetylation/deacetylation). In these notes we will concentrate on the ways to adapt the CRISPR/cas9 system for epigenetic DNA modification of specific regions of interest. The modular organization represents a universal principal, that allows to create infinite number of functions with a limited number of tools. CRISPR/cas9, in which each subunit can be adapted for a particular task, is an excellent example of this rule. Made of two main subunits, it can be modified for targeted delivery of foreign activity (effector, an epigenetic enzyme in our case) to a selected part of the genome. In doing this the CRISPR/cas9 system represents a unique method that allows the introduction of both genomic and epigenetic modifications. This chapter gives a detailed review of how to prepare DNA for the fully functional CRISPR/cas9 system, able to introduce required modifications in the region of interest. We will discuss specific requirements for each structural component of the system as well as for auxiliary elements (modules), which are needed to ensure efficient expression of the elements of the system within the cell and the needs of selection and visualization.


Assuntos
Epigenômica/métodos , Edição de Genes/métodos , Animais , Proteína 9 Associada à CRISPR/genética , Proteína 9 Associada à CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , DNA/química , Metilação de DNA/genética , Epigênese Genética/genética , Humanos , RNA Guia de Cinetoplastídeos/genética
13.
J Phys Chem Lett ; 12(23): 5547-5551, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34101473

RESUMO

We report on the nanoparticles composed of the catalytically synthesized Prussian Blue (PB) core stabilized with the nickel hexacyanoferrate (NiHCF) shell. Catalyzing hydrogen peroxide reduction, the resulting nanozymes (ø = 66 nm) display catalytic rate constants, which for pyrogallol or ferrocyanide are, respectively, 25 and 35 times higher than those for peroxidase enzyme. After more than half a year of storage at a room temperature, the core-shell PB-NiHCF nanozymes retain both their size and physicochemical properties; such stability is unreachable for the enzymes. Being immobilized, core-shell PB-NiHCF nanozymes (ø = 45 nm) result in a hydrogen peroxide sensor with a sensitivity similar to that of the sensor based on sole PB nanoparticles. However, whereas the latter response in hard inactivating conditions (25 min in 1 mM H2O2) drops down to 7.5%, the PB-NiHCF nanozymes-based sensor retains >75% of initial sensitivity. Application of the core-shell PB-NiHCF nanozymes "artificial peroxidase" would obviously open new horizons in elaboration of anti-inflammatory drugs and (bio)sensors.


Assuntos
Nanopartículas/química , Peroxidase/química , Catálise , Isoenzimas/análise , Isoenzimas/química , Microscopia Eletrônica de Transmissão/métodos , Nanopartículas/análise , Peroxidase/análise , Estabilidade Proteica
14.
J Cosmet Dermatol ; 20(5): 1505-1511, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33547864

RESUMO

BACKGROUND: Soft tissue filler injections are frequently performed with a relatively low number of severe adverse events reported. While venous complications have been described, the majority of adverse events are generally associated with the arterial vascular system. Intra-arterial product application can present with pain, skin discoloration, and potential tissue loss and/or injection related visual compromise. AIM: We present the clinical case and the consecutive symptomology of a 39-year-old woman injected with calcium hydroxylapatite at the zygomatic arch with five perpendicular needle (27G 12mm) supraperiosteal bolus injections of 0.2 cc per site. METHODS: Immediately after the injections, weakness, nausea, vomiting, and loss of consciousness occurred. Additionally, left-sided loss of sensation of her face, scalp, oral, and nasal mucosa occurred, with absence of left corneal reflex and ipsi-lateral ear congestion. Subsequently, left-sided masseteric atrophy and dysphagia occurred. RESULTS: One year after the injection procedure the sensory loss of her facial skin and scalp persisted, while the other symptoms improved. Medications involved in the symptomatic (not causal) partial recovery process were Dexamethasone, Vitamin B complex, Vinpocetine, Pentoxifyllin, and Thioctic acid. CONCLUSION: The symptoms presented and the time-related relationship to the injection procedure increases the likeliness of an association between the administration of the calcium hydroxylapatite product and a lesion of the trigeminal ganglion. The resulting symptoms can altogether be related to the functions of the ganglion. The connecting pathway between the injection site and the ganglion can be explained by the arterial vascular pathway.


Assuntos
Técnicas Cosméticas , Doenças do Nervo Trigêmeo , Adulto , Cálcio , Técnicas Cosméticas/efeitos adversos , Durapatita/efeitos adversos , Feminino , Humanos , Injeções
15.
Biomedicines ; 10(1)2021 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-35052745

RESUMO

Calcification is the major factor limiting the clinical use of bioprostheses. It may be prevented by the immobilization of bisphosphonic compounds (BPs) on the biomaterial. In this study, we assessed the accumulation and structure of calcium phosphate deposits in collagen-rich bovine pericardium (Pe) and elastin-rich porcine aortic wall (Ao) and bovine jugular vein wall (Ve) cross-linked with glutaraldehyde (GA) or diepoxy compound (DE). These tissues were then modified with pamidronic (PAM) acid or 2-(2'-carboxyethylamino)ethylidene-1,1-bisphosphonic (CEABA) acid. Tissue transformations were studied using Fourier-transform infrared spectroscopy. After subcutaneous implantation of the biomaterials in 220 rats, calcification dynamics were examined using atomic absorption spectrophotometry, light microscopy after von Kossa staining, and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy The calcium content in all GA-cross-linked tissues and DE-cross-linked Ao increased to 100-160 mg/g on day 60 after implantation. BPs prevented the accumulation of phosphates on the surface of all materials and most effectively inhibited calcification in GA-cross-linked Ao and DE-cross-linked Pe. PAM containing -OH in the R1 group was more effective than CEABA containing -H in R1. The calcification-inhibitory effect of BPs may be realized through their ability to block nucleation and prevent the growth of hydroxyapatite crystals.

16.
J Clin Med ; 10(24)2021 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-34945243

RESUMO

Impaired wound healing is one of the unsolved problems of modern medicine, affecting patients' quality of life and causing serious economic losses. Impaired wound healing can manifest itself in the form of chronic skin wounds or hypertrophic scars. Research on the biology and physiology of skin wound healing disorders is actively continuing, but, unfortunately, a single understanding has not been developed. The attention of clinicians to the biological and physiological aspects of wound healing in the skin is necessary for the search for new and effective methods of prevention and treatment of its consequences. In addition, it is important to update knowledge about genetic and non-genetic factors predisposing to impaired wound healing in order to identify risk levels and develop personalized strategies for managing such patients. Wound healing is a very complex process involving several overlapping stages and involving many factors. This thematic review focuses on the extracellular matrix of the skin, in particular its role in wound healing. The authors analyzed the results of fundamental research in recent years, finding promising potential for their transition into real clinical practice.

17.
Mater Sci Eng C Mater Biol Appl ; 118: 111473, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255052

RESUMO

Bioprosthetic heart valves made from bovine pericardium (BP) and porcine pericardium (PP) preserved with glutaraldehyde (GA) are commonly used in valve surgeries but prone to calcification in many patients. In this study, we compared BP and PP preserved with GA, ethylene glycol diglycidyl ether (DE), and 1,2,3,4,6-penta-O-{1-[2-(glycidyloxy)ethoxy]ethyl}-d-glucopyranose (PE). We studied the stabilities of DE and PE in preservation media along with the amino acid (AA) compositions, Fourier-transform infrared spectra, mechanical properties, surface morphologies, thermal stability, calcification, and the cytocompatibility of BP and PP treated with 0.625% GA, 5% DE, 2% PE, and alternating 5% DE and 2% PE for 3 + 11 d and 10 + 10 d, respectively. Both epoxides were stable in the water-buffer solutions (pH 7.4). DE provided high linkage densities in BP and PP owing to reactions with Hyl, Lys, His, Arg, Ser, and Tyr. PE reacted weakly with these AAs but strongly with Met. High cross-linking density obtained using the 10 d + 10 d method provided satisfactory thermal stability of biomaterials. The epoxy preservations improved cytocompatibility and resistance to calcification. PE enhanced the stress/strain properties of the xenogeneic pericardia, perhaps by forming nanostructures that were clearly visualised in BP using scanning electron microscopy. The DE + PE combination, in an alternating cross-linking manner, thus constitutes a promising option for developing bioprosthetic pericardia.


Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Animais , Bovinos , Reagentes de Ligações Cruzadas , Glutaral , Humanos , Pericárdio , Suínos
18.
PLoS Genet ; 3(12): e235, 2007 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-18166085

RESUMO

Prader-Willi syndrome (PWS [MIM 176270]) is a neurogenetic disorder characterized by decreased fetal activity, muscular hypotonia, failure to thrive, short stature, obesity, mental retardation, and hypogonadotropic hypogonadism. It is caused by the loss of function of one or more imprinted, paternally expressed genes on the proximal long arm of chromosome 15. Several potential PWS mouse models involving the orthologous region on chromosome 7C exist. Based on the analysis of deletions in the mouse and gene expression in PWS patients with chromosomal translocations, a critical region (PWScr) for neonatal lethality, failure to thrive, and growth retardation was narrowed to the locus containing a cluster of neuronally expressed MBII-85 small nucleolar RNA (snoRNA) genes. Here, we report the deletion of PWScr. Mice carrying the maternally inherited allele (PWScr(m-/p+)) are indistinguishable from wild-type littermates. All those with the paternally inherited allele (PWScr(m+/p-)) consistently display postnatal growth retardation, with about 15% postnatal lethality in C57BL/6, but not FVB/N crosses. This is the first example in a multicellular organism of genetic deletion of a C/D box snoRNA gene resulting in a pronounced phenotype.


Assuntos
Deleção de Genes , Transtornos do Crescimento/genética , RNA Nucleolar Pequeno/genética , Animais , Northern Blotting , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hibridização de Ácido Nucleico , Reação em Cadeia da Polimerase Via Transcriptase Reversa
19.
Talanta ; 215: 120922, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32312464

RESUMO

We present here wearable devices for continuous monitoring of diabetes and hypoxia based on continuous analysis of sweat. To induce sweating the clinically relevant procedure (pilocarpine electrophoresis) is used. Being a sufficient requirement for diagnostics, positive correlations in variation rates between glucose and lactate concentrations in sweat and the corresponding values in blood are shown. Continuous monitoring of human condition is possible only with the use of flow-through wearable devices providing a delivery of sweat to the biosensor almost immediately after secretion. Evaluating blood glucose through continuous sweat analysis upon glucose tolerance test, we clearly show that diabetics can actually be monitored reliably via non-invasive approach.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus/diagnóstico , Glucose/análise , Hipóxia/diagnóstico , Monitorização Fisiológica , Suor/química , Dispositivos Eletrônicos Vestíveis , Diabetes Mellitus/metabolismo , Glucose/metabolismo , Humanos , Hipóxia/metabolismo , Tamanho da Partícula , Propriedades de Superfície
20.
J Biomed Mater Res A ; 108(7): 1579-1588, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32176416

RESUMO

This study evaluated the ability of bisphosphonates (BPAs) of different molecular structures to mitigate the calcification of porcine aortic wall (PAW) and bovine jugular vein wall (BJVW). Tissues cross-linked with glutaraldehyde (GA) or diepoxide (DE) were modified with pamidronic acid (PAM), alendronic acid (ALE), neridronic acid (NER) (type 1 BPAs); 2-(2'-carboxyethylamino)ethylidene-1,1-bisphosphonic acid (CEABA), 2-(5-carboxypentylamino)ethylidene-1,1-bisphosphonic acid (CPABA) (type 2); and zoledronic acid (ZOL) (type 3). After implanting the tissue samples subcutaneously in 100 rats, calcification was examined using atomic absorption spectrophotometry (60-day explants) and light microscopy after von Kossa staining (10- and 30-day explants). The calcium contents in GA-BJVW and GA- and DE-PAW increased up to 100-120 mg/g after 60 days, while being 3 times lower in DE-BJVW. In modified and nonmodified PAW samples, calcium phosphates appeared by day 10 and were associated with elastic fibers and devitalized cellular elements. In all groups of BJVW samples, mineralization began in elastic fibers near the subendothelial layer. In addition, calcified collagen was found in the GA-BJVW samples. Minimal calcification was found in GA-PAW treated with type 1 BPAs and CEABA. For DE-PAW and GA-BJVW, the calcium level significantly decreased with PAM and CEABA. Meanwhile, ALE and NER were effective for DE-BJVW.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Bioprótese/efeitos adversos , Calcinose/etiologia , Difosfonatos/administração & dosagem , Elastina/efeitos adversos , Animais , Materiais Biocompatíveis/química , Calcinose/prevenção & controle , Bovinos , Difosfonatos/química , Difosfonatos/uso terapêutico , Elastina/química , Suínos
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