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1.
Microb Ecol ; 86(3): 1847-1855, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36708393

RESUMEN

Whether intraspecific phenotypic variation in saprobic fungi may be driven by the host of origin has received little attention. We addressed this issue by testing hypotheses using the model system Phlebiopsis gigantea, a wood destroying fungus associated with Picea abies and Pinus sylvestris, among others, and widely employed in practical forestry as a biological control agent. By examining approximately 60 sympatric P. gigantea isolates from both P. abies and P. sylvestris, we showed that the former grew in vitro significantly (P < 0.05) slower than the latter (average 5.56 mm/day vs. 6.84) while producing 1.8-fold significantly higher number of mitospores. An overall significant trade-off between these two phenotypic traits was detected, in particular for isolates originating from P. abies. Comparative inoculation experiments of a subsample of isolates and the assessment of mycelial growth in logs of both hosts allowed to reject the hypothesis that isolates are equally fit in terms of growth rate in wood of both hosts regardless of the host of origin. Tree models revealed that the growth rate of isolates was associated not only with the wood species in which the isolates were inoculated (P < 0.001), P. sylvestris being more rapidly colonized than P. abies, but also with the host of origin of isolates (P < 0.001). Results showed that P. gigantea isolates originating from different hosts differ phenotypically in terms of some key phenotypic traits demonstrating that a host-driven intraspecific phenotypic variation may occur in saprobic fungi.


Asunto(s)
Abies , Picea , Pinus sylvestris , Polyporales , Hongos , Pinus sylvestris/microbiología , Variación Biológica Poblacional , Picea/microbiología
2.
Appl Microbiol Biotechnol ; 107(2-3): 535-542, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36607404

RESUMEN

Studies on the chemical mechanisms of furfural formation showed the possibility to apply a new differential catalysis of hemicellulose - its depolymerisation and pentose dehydration to furfural. This change led to the increase in furfural yield and essential decrease of cellulose destruction. The lignocellulose residue that remains after the production of furfural may be subjected to enzymatic hydrolysis to glucose and the subsequent fermentation to ethanol. The remaining lignin appeared to be suitable for the production of additional various value-added products including medicinal mushrooms and laccase-containing enzyme complexes. Based on these developments, an innovative concept is proposed for the waste-free use of lignocellulose to obtain various valuable products. KEY POINTS: • New chemical mechanism of furfural production. • New lignocellulose pretreatment does not damage cellulose and lignin. • Lignocellulose may be processed using waste-free technology.


Asunto(s)
Etanol , Lignina , Lignina/metabolismo , Furaldehído , Celulosa , Hidrólisis , Fermentación
3.
Medicina (Kaunas) ; 53(2): 101-108, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28416171

RESUMEN

OBJECTIVE: The aim of this study was to compare treatment methods of the knee joint degenerative osteoarthritis, using autologous bone marrow-derived mononuclear cells and hyaluronic acid injections and observe prevalence of adverse effects in both groups. MATERIALS AND METHODS: A prospective randomized controlled clinical trial was carried out. The analysis of pain and changes in osteoarthritis symptoms after a single intra-articular bone marrow-derived mononuclear cell injection into the knee joint in the Kellgren-Lawrence stage II-III osteoarthritis during the 12-month period were performed. The results were compared with the control group treated routinely by hyaluronic acid injections therapy. A therapy group of patients (n=28) received single bone marrow-derived mononuclear cell intra-articular injections. A control group of patients (n=28) was treated with a total of three sodium hyaluronate intra-articular injections each one performed a week apart. The clinical results were obtained using the Knee Osteoarthritis Outcome Score (KOOS) and the Knee Society Score (KSS) before and 3, 6, and 12 months after injection. RESULTS: A statistically significant improvement was observed in the mononuclear cell group over the starting point in all scores. At the endpoint at month 12, the KOOS score improved significantly (P<0.05) on the pain subscale (+25.44), activity and daily living subscale (+21.36), quality of life subscale (+28.83), and total KOOS (+18.25). The KSS score also demonstrated a significant improvement on the symptoms subscale (+25.42) and the function subscale (+38.32) (P<0.001). The KOOS symptoms and sports subscales improved without statistical significance. The difference between the control group treated with hyaluronic acid versus the bone marrow-derived mononuclear cells group at time points 6 and 12 months demonstrated a statistically significant (P<0.05) superiority in the KOOS pain subscale over the hyaluronic acid group. In both groups serious adverse effects were not observed. CONCLUSIONS: The intra-articular injection of bone marrow-derived mononuclear cells is a safe manipulation with no side effects during the 12-month period. This treatment provides statistically significant clinical improvement between the starting point and 1, 3, 6, and 12 months after. When compared to hyaluronic acid treatment, better pain relief in the long-term period of mononuclear cell group was observed.


Asunto(s)
Trasplante de Médula Ósea , Ácido Hialurónico/administración & dosificación , Monocitos/trasplante , Osteoartritis de la Rodilla/terapia , Anciano , Trasplante de Médula Ósea/efectos adversos , Femenino , Humanos , Ácido Hialurónico/efectos adversos , Inyecciones Intraarticulares , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/tratamiento farmacológico , Osteoartritis de la Rodilla/cirugía , Resultado del Tratamiento
4.
Mycorrhiza ; 26(5): 465-73, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26861482

RESUMEN

We examined differences in fine root morphology, mycorrhizal colonisation and root-inhabiting fungal communities between Picea abies individuals infected by Heterobasidion root-rot compared with healthy individuals in four stands on peat soils in Latvia. We hypothesised that decreased tree vitality and alteration in supply of photosynthates belowground due to root-rot infection might lead to changes in fungal communities of tree roots. Plots were established in places where trees were infected and in places where they were healthy. Within each stand, five replicate soil cores with roots were taken to 20 cm depth in each root-rot infected and uninfected plot. Root morphological parameters, mycorrhizal colonisation and associated fungal communities, and soil chemical properties were analysed. In three stands root morphological parameters and in all stands root mycorrhizal colonisation were similar between root-rot infected and uninfected plots. In one stand, there were significant differences in root morphological parameters between root-rot infected versus uninfected plots, but these were likely due to significant differences in soil chemical properties between the plots. Sequencing of the internal transcribed spacer of fungal nuclear rDNA from ectomycorrhizal (ECM) root morphotypes of P. abies revealed the presence of 42 fungal species, among which ECM basidiomycetes Tylospora asterophora (24.6 % of fine roots examined), Amphinema byssoides (14.5 %) and Russula sapinea (9.7 %) were most common. Within each stand, the richness of fungal species and the composition of fungal communities in root-rot infected versus uninfected plots were similar. In conclusion, Heterobasidion root-rot had little or no effect on fine root morphology, mycorrhizal colonisation and composition of fungal communities in fine roots of P. abies growing on peat soils.


Asunto(s)
Basidiomycota/fisiología , Picea/microbiología , Enfermedades de las Plantas/microbiología , Raíces de Plantas/microbiología , Suelo/química , Micorrizas/fisiología , Raíces de Plantas/anatomía & histología
5.
BMC Dev Biol ; 14: 10, 2014 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-24552295

RESUMEN

BACKGROUND: Important knowledge about the role of vitamin A in vertebrate heart development has been obtained using the vitamin A-deficient avian in ovo model which enables the in vivo examination of very early stages of vertebrate heart morphogenesis. These studies have revealed the critical role of the vitamin A-active form, retinoic acid (RA) in the regulation of several developmental genes, including the important growth regulatory factor, transforming growth factor-beta2 (TGFß2), involved in early events of heart morphogenesis. However, this in ovo model is not readily available for elucidating details of molecular mechanisms determining RA activity, thus limiting further examination of RA-regulated early heart morphogenesis. In order to obtain insights into RA-regulated gene expression during these early events, a reliable in vitro model is needed. Here we describe a cell culture that closely reproduces the in ovo observed regulatory effects of RA on TGFß2 and on several developmental genes linked to TGFß signaling during heart morphogenesis. RESULTS: We have developed an avian heart forming region (HFR) cell based in vitro model that displays the characteristics associated with vertebrate early heart morphogenesis, i.e. the expression of Nkx2.5 and GATA4, the cardiogenesis genes, of vascular endothelial growth factor (VEGF-A), the vasculogenesis gene and of fibronectin (FN1), an essential component in building the heart, and the expression of the multifunctional genes TGFß2 and neogenin (NEO). Importantly, we established that the HFR cell culture is a valid model to study RA-regulated molecular events during heart morphogenesis and that the expression of TGFß2 as well as the expression of several TGFß2-linked developmental genes is regulated by RA. CONCLUSIONS: Our findings reported here offer a biologically relevant experimental in vitro system for the elucidation of RA-regulated expression of TGFß2 and other genes involved in vertebrate early cardiovascular morphogenesis.


Asunto(s)
Corazón/efectos de los fármacos , Morfogénesis/efectos de los fármacos , Miocardio/citología , Vitamina A/farmacología , Animales , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Células Cultivadas , Embrión de Pollo , Pollos , Ensayo de Inmunoadsorción Enzimática , Fibronectinas/genética , Factor de Transcripción GATA4/genética , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Corazón/embriología , Proteínas de Homeodominio/genética , Morfogénesis/genética , Miocardio/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Técnicas de Cultivo de Tejidos , Factores de Transcripción/genética , Factor de Crecimiento Transformador beta2/genética , Factor de Crecimiento Transformador beta2/metabolismo , Tretinoina/farmacología , Factor A de Crecimiento Endotelial Vascular/genética , Vertebrados/embriología , Vertebrados/genética , Vitaminas/farmacología
6.
ACS Omega ; 7(44): 40324-40332, 2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36385891

RESUMEN

A new composite metal-insulator-metal (MIM) system consisting of exceptionally dense non-close-packed (NCP) arrays of gold or silver nanoparticles, porous anodic aluminum oxide (PAAO), and bulk aluminum substrate interacts strongly with visible light and may become a very useful component for optical applications. The proposed MIM structure can be synthesized using accessible lithography-free chemical and physical processes (anodization and capillary force assisted colloidal particle deposition) that are suitable for the low-cost production of specialized devices. Here, we present a systematic study to determine the essential MIM structure parameters (nanoparticle size and PAAO layer thickness) for localized surface plasmon resonance (LSPR) refractometric sensing. A performance comparison was done by recording the spectra of scattered light upon angled illumination in media with different refractive indices. A clear advantage for maximizing the signal to background ratio was observed in the case of 60 and 80 nm Au nanoparticles with a PAAO thickness in a narrow range between 300 and 375 nm. Sensitivity exceeding a 200 nm peak wavelength shift per refractive index unit was found for 60 nm Au nanoparticles on approximately 500-nm-thick PAAO. The experimental observations were supported by finite-difference time-domain (FDTD) simulations.

7.
Cartilage ; 10(1): 26-35, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29373926

RESUMEN

OBJECTIVES: To evaluate the main symptoms of knee osteoarthritis (OA) and tissue structure changes after a single dose bone marrow-derived mononuclear cell (BM MNC) intra articular injection. Case series study. Patients with knee OA Kellgren Lawrence (K-L) grade II and III received 1 injection of BM MNC. The clinical results were analyzed with the Knee injury and Osteoarthritis Outcome Score (KOOS) and Knee Society Score (KSS) before, 3, 6, and 12 months after injection. Radiological evaluation was performed with a calibrated x-ray and the magnetic resonance (MR) imaging before and 6 to 7 months postinjection. RESULTS: A total of 34 knees were treated with BM MNC injections. Mean (±SD) age of patient group was 53.96 ± 14.15 years; there were 16 males, 16 females, KL grade II, 16; KL grade III, 18. The average injected count of BM MNCs was 45.56 ± 34.94 × 106 cells. At the endpoint of 12 months 65% of patients still had minimal perceptible clinical improvement of the KOOS total score. The mean improvement of KOOS total score was +15.3 and of the KSS knee score was +21.45 and the function subscale +27.08 ( P < 0.05) points. The Whole Organ Magnetic Resonance Imaging Score (WORMS) improved from 44.31 to 42.93 points ( P < 0.05). No adverse effects after the BM-MNC injection were observed. CONCLUSIONS: The single dose BM MNC partially reduces clinical signs of the knee osteoarthritis stage II/III and in some cases, decreases degenerative changes in the joint building tissue over 12-month period.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas/métodos , Leucocitos Mononucleares/trasplante , Osteoartritis de la Rodilla/terapia , Adulto , Femenino , Estudios de Seguimiento , Humanos , Inyecciones Intraarticulares , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/diagnóstico por imagen , Osteoartritis de la Rodilla/patología , Radiografía , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
8.
Int J Med Mushrooms ; 16(6): 605-6015, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25404225

RESUMEN

Shiitake medicinal mushroom, Lentinus edodes, is among the most widely cultivated edible mushrooms in the world and is a well-studied source of nutrients and biologically active compounds. We have studied the influence of the dietary supplement of the polysaccharides containing a hot water extract of the mushroom L. edodes on the fruit fly Drosophila melanogaster in terms of food intake, body weight, life span, and age-related locomotor activity. L. edodes extract, when added to the D. melanogaster feeding substrate at a 0.003-0.030% concentration (calculated for the dry weight of the polysaccharide fraction) did not influence food intake or body weight of the flies. It increased the life span and locomotor activities of male flies but was associated with early mortality and decreased locomotor activity of female flies. We conclude that the observed anti-aging effects of L. edodes extracts in the male D. melanogaster are not the result of dietary restriction. We propose that D. melanogaster is a suitable model organism for researching the molecular basis of the anti-aging effect of the shiitake mushroom extracts and sex linkage of these effects.


Asunto(s)
Envejecimiento/efectos de los fármacos , Drosophila melanogaster/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Hongos Shiitake/química , Agua/química , Animales , Peso Corporal , Femenino , Calor , Masculino
9.
Stem Cell Rev Rep ; 5(4): 378-86, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20058201

RESUMEN

Mesenchymal stem cells (MSCs) have been isolated from a variety of human tissues, e.g., bone marrow, adipose tissue, dermis, hair follicles, heart, liver, spleen, dental pulp. Due to their immunomodulatory and regenerative potential MSCs have shown promising results in preclinical and clinical studies for a variety of conditions, such as graft versus host disease (GvHD), Crohn's disease, osteogenesis imperfecta, cartilage damage and myocardial infarction. MSC cultures are composed of heterogeneous cell populations. Complications in defining MSC arise from the fact that different laboratories have employed different tissue sources, extraction, and cultivation methods. Although cell-surface antigens of MSCs have been extensively explored, there is no conclusive evidence that unique stem cells markers are associated with these adult cells. Therefore the aim of this study was to examine expression of embryonic stem cell markers Oct4, Nanog, SOX2, alkaline phosphatase and SSEA-4 in adult mesenchymal stem cell populations derived from bone marrow, adipose tissue, dermis and heart. Furthermore, we tested whether human mesenchymal stem cells preserve tissue-specific differences under in vitro culture conditions. We found that bone marrow MSCs express embryonic stem cell markers Oct4, Nanog, alkaline phosphatase and SSEA-4, adipose tissue and dermis MSCs express Oct4, Nanog, SOX2, alkaline phosphatase and SSEA-4, whereas heart MSCs express Oct4, Nanog, SOX2 and SSEA-4. Our results also indicate that human adult mesenchymal stem cells preserve tissue-specific differences under in vitro culture conditions during early passages, as shown by distinct germ layer and embryonic stem cell marker expression patterns. Studies are now needed to determine the functional role of embryonic stem cell markers Oct4, Nanog and SOX2 in adult human MSCs.


Asunto(s)
Tejido Adiposo/metabolismo , Médula Ósea/metabolismo , Dermis/metabolismo , Células Madre Embrionarias/metabolismo , Miocardio/metabolismo , Tejido Adiposo/citología , Biomarcadores/metabolismo , Separación Celular , Células Cultivadas , Dermis/citología , Células Madre Embrionarias/citología , Humanos , Persona de Mediana Edad , Miocardio/citología
10.
Cytotechnology ; 58(3): 153-62, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19219561

RESUMEN

This study investigated conditions for optimal in vitro propagation of human skin-derived mesenchymal stem cells (S-MSC). Forty primary skin-derived precursor cell (SKP) cultures were established from both male and female donors (age 29-65 years) and eight of them were randomly selected for in-depth characterization. Effects of basic fibroblast growth factor (FGF-2), epidermal growth factor (EGF), leukemia inhibiting factor (LIF) and dibutyryl-cyclic adenosine monophosphate (db-cAMP) on S-MSC proliferation were investigated. Primary SKP cultures were >95% homogenous for CD90, CD73, and CD105 marker expression enabling to classify these cells as S-MSC. FGF-2 dose-dependent stimulation was observed in low serum medium only, whereas EGF neither stimulated S-MSC proliferation nor potentates the effect of FGF-2. Pronounced donor to donor differences among S-MSC cultures were observed in 3-day proliferation assay. This study demonstrates that homogenous S-MSC populations can be reproducibly isolated from individual donors of different age. Optimal cell culture conditions for in vitro propagation of S-MSC are B27 supplemented or low serum media with FGF-2 (4 ng/ml). EGF and LIF as well as db-cAMP are dispensable for S-MSC proliferation.

11.
J Virol ; 81(10): 5349-61, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17344292

RESUMEN

The epigenetic status of integrated adenovirus type 12 (Ad12) DNA in hamster cells cultivated for about 4 decades has been investigated. Cell line TR12, a fibroblastic revertant of the Ad12-transformed epitheloid hamster cell line T637 with 15 copies of integrated Ad12 DNA, carries one Ad12 DNA copy plus a 3.9-kbp fragment from a second copy. The cellular insertion site for the Ad12 integrate, identical in both cell lines, is a >5.2-kbp inverted DNA repeat. The Ad12 transgenome is packaged around nucleosomes. The cellular junction is more sensitive to micrococcal nuclease at Ad12-occupied sites than at unoccupied sites. Bisulfite sequencing reveals complete de novo methylation in most of the 1,634 CpGs of the integrated viral DNA, except for its termini. Isolated unmethylated CpGs extend over the entire Ad12 integrate. The fully methylated transgenome segments are characterized by promoter silencing and histone H3 and H4 hypoacetylation. Nevertheless, there is minimal transcriptional activity of the late viral genes controlled by the fully methylated major late promoter of Ad12 DNA.


Asunto(s)
Adenoviridae/genética , ADN Viral/genética , Epigénesis Genética , Provirus/genética , Acetilación , Adenoviridae/fisiología , Animales , Línea Celular , Línea Celular Transformada , Cricetinae , ADN/química , ADN/metabolismo , Metilación de ADN , Histonas/química , Nucleasa Microcócica/metabolismo , Nucleosomas/genética , Transcripción Genética , Cultivo de Virus , Integración Viral
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