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1.
Animals (Basel) ; 14(9)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38731296

RESUMEN

BACKGROUND: Mesenchymal stem cells (MSCs) are increasingly trialed in cellular therapy applications in humans. They can also be applied to treat a range of diseases in animals, particularly in cattle to combat inflammatory conditions and aging-associated degenerative disorders. We sought to demonstrate the feasibility of obtaining MSCs from adipose tissue and characterizing them using established assays. METHODS: Bovine adipose MSCs (BvAdMSCs) were isolated using in-house optimized tissue digestion protocols and characterized by performing a colony formation assay, cell growth assessments, cell surface marker analysis by immunocytochemistry and flow cytometry, osteogenic and adipogenic differentiation, and secretion of indoleamine 2,3-dioxygenease (IDO). RESULTS: Our results demonstrate the feasibility of successful MSC isolation and culture expansion from bovine adipose tissues with characteristic features of colony formation, in vitro multilineage differentiation into osteogenic and adipogenic lineages, and cell surface marker expression of CD105, CD73, CD90, CD44, and CD166 with negative expression of CD45. BvAdMSCs secreted significant amounts of IDO with or without interferon-gamma stimulation, indicating ability for immunomodulation. CONCLUSIONS: We report a viable approach to obtaining autologous adipose-derived MSCs that can be applied as potential adjuvant cell therapy for tissue repair and regeneration in cattle. Our methodology can be utilized by veterinary cell therapy labs for preparing MSCs for disease management in cattle.

2.
J Biol Eng ; 17(1): 44, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37434264

RESUMEN

Mesenchymal stem/stromal cells (MSCs) have been carefully examined to have tremendous potential in regenerative medicine. With their immunomodulatory and regenerative properties, MSCs have numerous applications within the clinical sector. MSCs have the properties of multilineage differentiation, paracrine signaling, and can be isolated from various tissues, which makes them a key candidate for applications in numerous organ systems. To accentuate the importance of MSC therapy for a range of clinical indications, this review highlights MSC-specific studies on the musculoskeletal, nervous, cardiovascular, and immune systems where most trials are reported. Furthermore, an updated list of the different types of MSCs used in clinical trials, as well as the key characteristics of each type of MSCs are included. Many of the studies mentioned revolve around the properties of MSC, such as exosome usage and MSC co-cultures with other cell types. It is worth noting that MSC clinical usage is not limited to these four systems, and MSCs continue to be tested to repair, regenerate, or modulate other diseased or injured organ systems. This review provides an updated compilation of MSCs in clinical trials that paves the way for improvement in the field of MSC therapy.

3.
Materials (Basel) ; 15(23)2022 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36500133

RESUMEN

In this paper, the features of radiation compensation of wide-gap semiconductors are discussed, considering the case study of silicon carbide. Two classical methods of concentration determination are compared and analyzed: capacitance-voltage (C-V) and current-voltage (I-V) characteristics. The dependence of the base resistance in high-voltage 4H-SiC Schottky diodes on the dose of irradiation by electrons and protons is experimentally traced in the range of eight orders of magnitude. It is demonstrated that the dependence of the carrier concentration on the irradiation dose can be determined unambiguously and reliably in a very wide range of compensation levels, based on the results of measuring the I-V characteristics. It is shown that the determination of the carrier removal rate using the I-V characteristics is more correct than using the C-V characteristics, especially in the case of high radiation doses.

4.
Sci Total Environ ; 813: 152281, 2022 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-34942249

RESUMEN

This is the first Europe-wide comprehensive assessment of the climatological and physiological information recorded by hydrogen isotope ratios in tree-ring cellulose (δ2Hc) based on a unique collection of annually resolved 100-year tree-ring records of two genera (Pinus and Quercus) from 17 sites (36°N to 68°N). We observed that the high-frequency climate signals in the δ2Hc chronologies were weaker than those recorded in carbon (δ13Cc) and oxygen isotope signals (δ18Oc) but similar to the tree-ring width ones (TRW). The δ2Hc climate signal strength varied across the continent and was stronger and more consistent for Pinus than for Quercus. For both genera, years with extremely dry summer conditions caused a significant 2H-enrichment in tree-ring cellulose. The δ2Hc inter-annual variability was strongly site-specific, as a result of the imprinting of climate and hydrology, but also physiological mechanisms and tree growth. To differentiate between environmental and physiological signals in δ2Hc, we investigated its relationships with δ18Oc and TRW. We found significant negative relationships between δ2Hc and TRW (7 sites), and positive ones between δ2Hc and δ18Oc (10 sites). The strength of these relationships was nonlinearly related to temperature and precipitation. Mechanistic δ2Hc models performed well for both genera at continental scale simulating average values, but they failed on capturing year-to-year δ2Hc variations. Our results suggest that the information recorded by δ2Hc is significantly different from that of δ18Oc, and has a stronger physiological component independent from climate, possibly related to the use of carbohydrate reserves for growth. Advancements in the understanding of 2H-fractionations and their relationships with climate, physiology, and species-specific traits are needed to improve the modelling and interpretation accuracy of δ2Hc. Such advancements could lead to new insights into trees' carbon allocation mechanisms, and responses to abiotic and biotic stress conditions.


Asunto(s)
Celulosa , Árboles , Isótopos de Carbono/análisis , Bosques , Hidrógeno , Isótopos de Oxígeno/análisis
5.
Opt Lett ; 47(1): 86-89, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34951887

RESUMEN

The generation of terahertz radiation in a photoconductive emitter based on nitrogen-doped single-crystal diamond was realized for the first time. Under 400 nm femtosecond laser pumping, the performance of diamond antennas with different dopant levels was investigated and compared with a reference ZnSe antenna. Terahertz waveforms and corresponding spectra were measured. A low saturation level for high-nitrogen-containing diamond substrate was revealed. The results indicate the prospects of doped diamond as a material for high-efficiency large-aperture photoconductive antennas.

6.
Psychol Russ ; 15(4): 159-169, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761718

RESUMEN

Background: It is known that some genes regulate neurochemical metabolism, and their polymorphisms affect cognitive performance, including the ability to categorize emotionally significant information. Objective: The aim of our study was to analyze the recognition of emotional and neutral visual scenes in carriers of different polymorphic variants of the MAOA, COMT, DRD4, and 5HT2A genes. Design: The study sample consisted of 87 university students (Caucasians, women 63%, average age 20.4±2.6 years). The genotypes of the COMT, 5HT2A, and DRD4 genes were determined by polymerase chain reaction. Agarose gel electrophoresis was used to determine the number of tandem repeats of the MAOA gene. Three hundred sixty (360) photographic images of scenes of different emotional valence (positive, negative, and neutral - 120 images for each category) were used as stimuli. These images were classified by expert assessments. The images were presented in a random sequence. The exposure time was 700 ms. The research participants were asked to determine the emotional valence of each scene. Results: We found that only the COMT gene genotype affected the recognition of emotional and neutral visual scenes. Carriers of the COMT Val/Val genotype, which causes dopamine to stay in the synaptic space for a shorter time, are better in recognizing and demonstrate higher sensitivity to the emotional content of scenes. Carriers of the Val/Met genotype demonstrated the worst ability to differentiate the emotional valence of visual scenes. Conclusion: This study has shown that the length of stay of monoamines in the synaptic space regulated by the COMT gene affects the recognition of emotional visual information.

7.
Materials (Basel) ; 14(17)2021 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-34501066

RESUMEN

The radiation hardness of silicon carbide with respect to electron and proton irradiation and its dependence on the irradiation temperature are analyzed. It is shown that the main mechanism of SiC compensation is the formation of deep acceptor levels. With increasing the irradiation temperature, the probability of the formation of these centers decreases, and they are partly annealed out. As a result, the carrier removal rate in SiC becomes ~6 orders of magnitude lower in the case of irradiation at 500 °C. Once again, this proves that silicon carbide is promising as a material for high-temperature electronics devices.

8.
Opt Lett ; 45(18): 5205-5208, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32932491

RESUMEN

We report a new method for excitation of magnetic resonance in an optically aligned atomic ensemble. It employs a comb-like rf field acting on the end sublevels of the Fg=1 state separated by the doubled Zeeman frequency. This approach provides a resonance without substructures associated with the quadratic Zeeman shift. A theoretical explanation of the effect is given in terms of the two-quantum transition |Fg=1,mFg=-1⟩⇆|Fg=1,mFg=1⟩ and is corroborated by an experiment with 87Rb atoms. Possible advantages of the approach and its range of applicability are discussed.

9.
J Am Soc Mass Spectrom ; 30(10): 1850-1856, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31111415

RESUMEN

Mono-ligation kinetics were measured for ammonia reacting with atomic cations in the first two groups of the periodic table (K+, Rb+, Cs+ and Ca+, Sr+, Ba+). Also, mono-ligation energies were computed using density functional theory (DFT) in an attempt to assess the role of non-covalent electrostatic interactions in these chemical reactions. The measurements were performed at room temperature in helium bath gas at 0.35 Torr using an inductively coupled plasma/selected-ion flow tube (ICP/SIFT) tandem mass spectrometer. Rate coefficients are reported for ammonia addition, the only reaction channel that was observed with all these cations. A systematic decrease in the rate of addition of NH3 was observed for both group 1 and 2 cations going down the periodic table. The computational studies predict a decrease in the adduct binding energy and an increase in the bond separation going down groups 1 and 2 of the periodic table and provide some insight into the role of the extra selectron in the group 2 radical cations in ligand bonding. A correlation is seen between the efficiency of ligation and the binding energy of the adduct ion and attributed to the lifetime of the intermediate encounter complex against back dissociation which is dependent on its well depth. Higher-order additions of ammonia were also observed. Remarkable differences in the extent and kinetics were seen between the group 1 and 2 cations, and these were attributed to the occurrence of ammonia solvation of the extra s electron in the higher-order adducts of the alkaline earth cations.

10.
Eur J Mass Spectrom (Chichester) ; 25(1): 44-49, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30773917

RESUMEN

The kinetics of ammonia ligation to atomic first and second row transition metal cations were measured in an attempt to assess the role of ligand field effects in gas-phase ion-molecule reaction kinetics. Measurements were performed at 295 ± 2 K in helium bath gas at 0.35 Torr using an inductively coupled plasma/selected-ion flow tube tandem mass spectrometer. The atomic cations were produced at ca. 5500 K in an inductively coupled plasma source and were allowed to decay radiatively and to thermalize by collisions with argon and helium atoms prior to reaction. A strong correlation was observed across the periodic table between the measured rate coefficients for ammonia ligation and measured/calculated bond dissociation energies. A similar strong correlation is seen with the ligand field stabilization energy. So ligand field stabilization energies should provide a useful predictor of relative rates of ligation of atomic metal ions.

11.
J Environ Manage ; 210: 239-254, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29348059

RESUMEN

Reducing fertilizer use is a priority in the quest for sustainable forestry systems. In short rotation Eucalyptus plantations, NPK pellets are routinely added to the seedling's top soil layer at planting, potentially leading to increased seedling mortality, nutrient loss and environmental degradation. To address this triple challenge, the development of efficient fertilization practices is essential. In the present work, we synthesized a crosslinked acrylic-cellulosic superabsorbent composite (SAPH-BAL) containing small amounts of specific nutrients integrated in the polymer matrix. We analyzed the composite's chemical and rheological properties, and assessed the viability of Eucalyptus plantations supplied with it at planting. Physiological measurements confirmed the suitability of SAPH-BAL in greenhouse-grown potted seedlings subjected to different growth conditions, showing that it efficiently delivers nutrients while protecting seedlings from drought stress. Field experiments carried out at ten South American locations covering an ample range of environmental conditions confirmed the beneficial effect of SAPH-BAL on growth and survival in comparison to the conventional fertilization scheme (superabsorbent + 75 g NPK). Furthermore, it was found that plants treated with SAPH-BAL were less affected by the differences in rainfall regimes during the experiments compared to those fertilized conventionally. To the best of our knowledge this is the first report describing the successful use of superabsorbents for root targeted delivery of fertilizers in forestry operations.


Asunto(s)
Fertilizantes , Agricultura Forestal , Conservación de los Recursos Naturales , Eucalyptus , Suelo , Agua
12.
Sci Transl Med ; 7(305): 305ra147, 2015 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-26378247

RESUMEN

Each year, 500,000 patients are treated with radiotherapy for head and neck cancer, resulting in relatively high survival rates. However, in 40% of patients, quality of life is severely compromised because of radiation-induced impairment of salivary gland function and consequent xerostomia (dry mouth). New radiation treatment technologies enable sparing of parts of the salivary glands. We have determined the parts of the major salivary gland, the parotid gland, that need to be spared to ensure that the gland continues to produce saliva after irradiation treatment. In mice, rats, and humans, we showed that stem and progenitor cells reside in the region of the parotid gland containing the major ducts. We demonstrated in rats that inclusion of the ducts in the radiation field led to loss of regenerative capacity, resulting in long-term gland dysfunction with reduced saliva production. Then we showed in a cohort of patients with head and neck cancer that the radiation dose to the region of the salivary gland containing the stem/progenitor cells predicted the function of the salivary glands one year after radiotherapy. Finally, we showed that this region of the salivary gland could be spared during radiotherapy, thus reducing the risk of post-radiotherapy xerostomia.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Glándula Parótida/efectos de la radiación , Radioterapia/métodos , Glándulas Salivales/patología , Glándulas Salivales/efectos de la radiación , Células Madre/citología , Animales , Humanos , Ratones , Glándula Parótida/metabolismo , Calidad de Vida , Radioterapia/efectos adversos , Ratas , Saliva/metabolismo , Glándulas Salivales/metabolismo , Xerostomía
14.
Opt Lett ; 37(16): 3369-71, 2012 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-23381260

RESUMEN

The processes, induced by local action of the IR femtosecond laser pulse (λ=1.2 µm, τ=250 fs) in the bulk of silicon monocrystal, are studied. Infrared femtosecond interferometry was for the first time applied for visualization of beam propagation inside opaque materials. Dependences of laser-induced variation of material polarizability on pulse energy were obtained and essential wave-packet spreading in space was revealed. This leads to huge delocalization of light-scattering outside the beam caustic exceeds 99% of pulse energy. This effect results in extremely high optical damage threshold of crystalline silicon bulk-irreversible changes in material structure and optical properties were not observed for pulse energy up to 90 µJ. The role of beam Kerr self-focusing and defocusing by an electron-hole plasma inside c:Si is discussed.

15.
J Phys Chem A ; 113(19): 5602-11, 2009 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-19371125

RESUMEN

Reactions of methane have been measured with 59 atomic metal cations at room temperature in helium bath gas at 0.35 Torr using an inductively-coupled plasma/selected-ion flow tube (ICP/SIFT) tandem mass spectrometer. The atomic cations were produced at approximately 5500 K in an ICP source and allowed to decay radiatively and to thermalize by collisions with argon and helium atoms prior to reaction. Rate coefficients and product distributions are reported for the reactions of fourth-row atomic cations from K(+) to Se(+), of fifth-row atomic cations from Rb(+) to Te(+) (excluding Tc(+)), of sixth-row atomic cations from Cs(+) to Bi(+), and of the lanthanide cations from La(+) to Lu(+) (excluding Pm(+)). Two primary reaction channels were observed: C-H bond insertion with elimination of H(2), and CH(4) addition. The bimolecular H(2) elimination was observed in the reactions of CH(4) with As(+), Nb(+), and some sixth-row metal cations, i.e., Ta(+), W(+), Os(+), Ir(+), Pt(+); secondary and higher-order H(2) elimination was observed exclusively for Ta(+), W(+), and Ir(+) ions. All other transition-metal cations except Mn(+) and Re(+) were observed to react with CH(4) exclusively by addition, and up to two methane molecules were observed to add sequentially to most transition-metal ions. CH(4) addition was also observed for Ge(+), Se(+), La(+), Ce(+), and Gd(+) ions, while the other main-group and lanthanide cations did not react measurably with methane.

16.
Inorg Chem ; 45(24): 9646-53, 2006 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-17112259

RESUMEN

Results are reported for experimental measurements of the room-temperature chemical reactions between ground-state Hg*+ ions and 16 important environmental and biological gases: SF6, CO, CO2, N2O, D2O, CH4, CH3F, O2, CH3Cl, OCS, CS2, NH3, C6F6, NO2, NO*, and C6H6. The inductively coupled plasma/selected-ion flow tube tandem mass spectrometer used for these measurements has provided both rate and equilibrium constants. Efficient electron transfer (>19%) is observed with CS2, NH3, C6F6, NO2, NO*, and C6H6, molecular addition occurs with D2O, CH4, CH3F, CH3Cl, and OCS, and SF6, CO, CO2, N2O, and O2 showed no measurable reactivity with Hg*+. Theory is used to explore the stabilities and structures of both the observed and unobserved molecular adducts of Hg*+, and reasonable agreement is obtained with experimental observations, given the uncertainties of the theory and experiments. A correlation is reported between the Hg*+ and proton affinities of the ligands investigated. Solvation of Hg*+ with formic acid was observed to increase the rate of electron transfer from NO* by more than 20%.

19.
Minerva Anestesiol ; 69(4): 320-3, 2003 Apr.
Artículo en Italiano | MEDLINE | ID: mdl-12766727

RESUMEN

ICU nurses hold an important role in the management of septic patients underlining with their ability to recognize SIRS that is the first step in the proinflammatory and procoagulant cascade following an infection. Early and timely approach to organ dysfunction can indeed modify the damages due to hypoperfusion. The ability to recognize organ dysfunction using different monitoring devices available should be part of the nursing attitudes.


Asunto(s)
Cuidados Críticos/métodos , Sepsis/diagnóstico , Sepsis/enfermería , Sistema Nervioso Central/fisiopatología , Humanos , Monitoreo Fisiológico , Sepsis/fisiopatología
20.
Minerva Chir ; 53(6): 531-4, 1998 Jun.
Artículo en Italiano | MEDLINE | ID: mdl-9774847

RESUMEN

A rare case of peritonitis by cecal perforated diverticulum which was diagnosed after surgery by histology is reported. Preoperative diagnosis is often ignored and, in rare cases, is not always clear at laparotomy. Clinical aspects, diagnostic procedures, histological picture and surgical treatment are described. In the literature diverticula are classified as "solitary" and "multiple", "congenital" and "acquired", "true" and "false" and finally "usual type" and "hidden variant". The treatment of cecal acute diverticulitis is, in the majority of patients, surgery. Simple resection of the diverticulum and suture of the breach in double layer is the elective operation of non-complicated diverticulum or with an inflamed projection from the cecal wall ("usual type"). Segmental resection of colon or "right hemicolectomy" is recommended when a precise diagnosis is not possible and in complicated diverticula ("hidden variant"). On the basis of personal experience it is underlined that diagnosis is rarely made preoperatively since the clinical picture suggests an acute appendicitis. If there are some doubts for appendicitis, a incidental tumor or possible perforated diverticulum of the cecum should be considered and urgent surgery is mandatory.


Asunto(s)
Enfermedades del Ciego/complicaciones , Divertículo/complicaciones , Perforación Intestinal/etiología , Enfermedad Aguda , Enfermedades del Ciego/diagnóstico , Enfermedades del Ciego/cirugía , Ciego/cirugía , Divertículo/diagnóstico , Divertículo/cirugía , Humanos , Perforación Intestinal/diagnóstico , Perforación Intestinal/cirugía , Masculino , Persona de Mediana Edad , Peritonitis/diagnóstico , Peritonitis/etiología , Peritonitis/cirugía
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