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1.
Psychosom Med ; 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38573035

RESUMEN

OBJECTIVE: The role of inflammation and neuroimmune mechanisms, which have been documented in various neuropsychiatric disorders including the seizure subtype of functional neurological disorder, remains unclear in functional movement disorders (FMD). To explore these mechanisms, we analyzed selected inflammatory markers in cerebrospinal fluid (CSF) in patients with FMD. METHODS: We compared CSF markers in 26 patients with clinically established FMD (20 females; mean (SD) age 43.3 (10.9); disease duration 3.9 (3); range 0.1-11 years; mean follow-up after lumbar puncture 4.3 (2) years, range 0.5-7 years) and 26 sex and age-matched clinical controls with non-inflammatory non-neurodegenerative neurological disorders, mostly sleep disorders. RESULTS: 65% of FMD patients vs. 15% of controls showed cytological abnormalities (i.e., increased white blood cells (WBC) count, signs of WBC activation, or both (odds ratio (OR) = 9.85, 95% confidence interval [2.37, 52.00], p < 0.01, corrected), with a significantly higher frequency of an isolated lymphocytic activation 35% vs. 0% (OR = ∞, 95% confidence interval [2.53, ∞], p < 0.05, corrected). There were no differences in CSF protein and albumin levels, quotient albumin, IgG index, and oligoclonal bands. CSF abnormalities were not associated with more severe motor symptoms or a higher frequency of depression in FMD. CONCLUSIONS: Our results suggest a possible involvement of immune mechanisms in the pathophysiology of (at least a subtype of) FMD that deserves further investigation.

2.
Small Methods ; 7(9): e2300258, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37248805

RESUMEN

A quantitative four-dimensional scanning transmission electron microscopy (4D-STEM) imaging technique (q4STEM) for local thickness estimation across amorphous specimen such as obtained by focused ion beam (FIB)-milling of lamellae for (cryo-)TEM analysis is presented. This study is based on measuring spatially resolved diffraction patterns to obtain the angular distribution of electron scattering, or the ratio of integrated virtual dark and bright field STEM signals, and their quantitative evaluation using Monte Carlo simulations. The method is independent of signal intensity calibrations and only requires knowledge of the detector geometry, which is invariant for a given instrument. This study demonstrates that the method yields robust thickness estimates for sub-micrometer amorphous specimen using both direct detection and light conversion 2D-STEM detectors in a coincident FIB-SEM and a conventional SEM. Due to its facile implementation and minimal dose reauirements, it is anticipated that this method will find applications for in situ thickness monitoring during lamella fabrication of beam-sensitive materials.

3.
Microorganisms ; 11(4)2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37110311

RESUMEN

Sample preparation protocols for conventional high voltage transmission electron microscopy (TEM) heavily rely on the usage of staining agents containing various heavy metals, most commonly uranyl acetate and lead citrate. However high toxicity, rising legal regulations, and problematic waste disposal of uranyl acetate have increased calls for the reduction or even complete replacement of this staining agent. One of the strategies for uranyless imaging is the employment of low-voltage transmission electron microscopy. To investigate the influence of different imaging and staining strategies on the final image of cyanobacterial cells, samples stained by uranyl acetate with lead citrate, as well as unstained samples, were observed using TEM and accelerating voltages of 200 kV or 25 kV. Moreover, to examine the possibilities of reducing chromatic aberration, which often causes issues when imaging using electrons of lower energies, samples were also imaged using a scanning transmission electron microscopy at 15 kV accelerating voltages. The results of this study demonstrate that low-voltage electron microscopy offers great potential for uranyless electron microscopy.

4.
Int J Pharm ; 634: 122695, 2023 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-36758881

RESUMEN

This contribution is focused on the preparation of a liposomal drug delivery system of erlotinib resisting the nebulization process that could be used for local treatment of non-small-cell lung cancer. Liposomes with different compositions were formulated to reveal their influence on the encapsulation efficiency of erlotinib. An encapsulation efficiency higher than 98 % was achieved for all vesicles containing phosphatidic acid (d ≈ 100 nm, ζ = - 43 mV) even in the presence of polyethylene glycol (d ≈ 150 nm, ζ = - 17 mV) which decreased this value in all other formulas. The three most promising formulations were nebulized by two air-jet and two vibrating mesh nebulizers, and the aerosol deposition in lungs was calculated by tools of computational fluid and particle mechanics. According to the numerical simulations and measurements of liposomal stability, air-jet nebulizers generated larger portion of the aerosol able to penetrate deeper into the lungs, but the delivery is likely to be more efficient when the formulation is administered by Aerogen Solo vibrating mesh nebulizer because of a higher portion of intact vesicles after the nebulization. The leakage of encapsulated drug from liposomes nebulized by this nebulizer was lower than 2 % for all chosen vesicles.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Administración por Inhalación , Liposomas , Clorhidrato de Erlotinib , Aerosoles y Gotitas Respiratorias , Nebulizadores y Vaporizadores , Sistemas de Liberación de Medicamentos , Pulmón , Tamaño de la Partícula , Broncodilatadores
5.
Polymers (Basel) ; 14(9)2022 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-35566928

RESUMEN

Production of polyhydroxyalkanoates (PHA), microbial biopolyesters, employing extremophilic microorganisms is a very promising concept relying on robustness of such organisms against microbial contamination, which provides numerous economic and technological benefits. In this work, we took advantage of the natural susceptibility of halophilic and thermophilic PHA producers to hypotonic lysis and we developed a simple and robust approach enabling effective isolation of PHA materials from microbial cells. The method is based on the exposition of microbial cells to hypotonic conditions induced by the diluted solution of sodium dodecyl sulfate (SDS) at elevated temperatures. Such conditions lead to disruption of the cells and release of PHA granules. Moreover, SDS, apart from its cell-disruptive function, also solubilizes hydrophobic components, which would otherwise contaminate PHA materials. The purity of obtained materials, as well as the yields of recovery, reach high values (values of purity higher than 99 wt.%, yields close to 1). Furthermore, we also focused on the removal of SDS from wastewater. The simple, inexpensive, and safe technique is based on the precipitation of SDS in the presence of KCl. The precipitate can be simply removed by decantation or centrifugation. Moreover, there is also the possibility to regenerate the SDS, which would substantially improve the economic feasibility of the process.

6.
Int J Biol Macromol ; 206: 977-989, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35314264

RESUMEN

Polyhydroxyalkanoates (PHA) are abundant microbial polyesters accumulated in the form of intracellular granules by numerous prokaryotes primarily as storage of carbon and energy. Apart from their storage function, the presence of PHA also enhances the robustness of the microbial cells against various stressors. In this work, we investigated the role of PHA in Cupriavidus necator, a model organism concerning PHA metabolism, for adaptation to osmotic pressure and copper ions. In long-term laboratory evolution experiments, the bacterial culture was cultivated in presence of elevated doses of sodium chloride or copper ions (incubations lasted 78 passages for Cu2+ and 68 passages for NaCl) and the evolved strains were compared with the wild-type strain in terms of growth and PHA production capacity, cell morphology (investigated by various electron microscopy techniques), activities of selected enzymes involved in PHA metabolism and other crucial metabolic pathways, the chemical composition of bacterial biomass (determined by infrared and Raman spectroscopy) and also considering robustness against various stressors. The results confirmed the important role of PHA metabolism for adaptation to both tested stressors.


Asunto(s)
Cupriavidus necator , Polihidroxialcanoatos , Cobre/metabolismo , Cupriavidus necator/metabolismo , Iones/metabolismo , Presión Osmótica , Cloruro de Sodio/metabolismo
7.
Bioengineering (Basel) ; 8(10)2021 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-34677214

RESUMEN

Polyhydroxyalkanoates (PHA) are microbial polyesters that have recently come to the forefront of interest due to their biodegradability and production from renewable sources. A potential increase in competitiveness of PHA production process comes with a combination of the use of thermophilic bacteria with the mutual use of waste substrates. In this work, the thermophilic bacterium Tepidimonas taiwanensis LMG 22826 was identified as a promising PHA producer. The ability to produce PHA in T. taiwanensis was studied both on genotype and phenotype levels. The gene encoding the Class I PHA synthase, a crucial enzyme in PHA synthesis, was detected both by genome database search and by PCR. The microbial culture of T. taiwanensis was capable of efficient utilization of glucose and fructose. When cultivated on glucose as the only carbon source at 50 °C, the PHA titers reached up to 3.55 g/L, and PHA content in cell dry mass was 65%. The preference of fructose and glucose opens the possibility to employ T. taiwanensis for PHA production on various food wastes rich in these abundant sugars. In this work, PHA production on grape pomace extracts was successfully tested.

8.
Microorganisms ; 9(5)2021 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-33923216

RESUMEN

Actinobacteria belonging to the genus Rubrobacter are known for their multi-extremophilic growth conditions-they are highly radiation-resistant, halotolerant, thermotolerant or even thermophilic. This work demonstrates that the members of the genus are capable of accumulating polyhydroxyalkanoates (PHA) since PHA-related genes are widely distributed among Rubrobacter spp. whose complete genome sequences are available in public databases. Interestingly, all Rubrobacter strains possess both class I and class III synthases (PhaC). We have experimentally investigated the PHA accumulation in two thermophilic species, R. xylanophilus and R. spartanus. The PHA content in both strains reached up to 50% of the cell dry mass, both bacteria were able to accumulate PHA consisting of 3-hydroxybutyrate and 3-hydroxyvalerate monomeric units, none other monomers were incorporated into the polymer chain. The capability of PHA accumulation likely contributes to the multi-extremophilic characteristics since it is known that PHA substantially enhances the stress robustness of bacteria. Hence, PHA can be considered as extremolytes enabling adaptation to extreme conditions. Furthermore, due to the high PHA content in biomass, a wide range of utilizable substrates, Gram-stain positivity, and thermophilic features, the Rubrobacter species, in particular Rubrobacter xylanophilus, could be also interesting candidates for industrial production of PHA within the concept of Next-Generation Industrial Biotechnology.

9.
Br J Ophthalmol ; 102(11): 1579-1585, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29378728

RESUMEN

BACKGROUND: Vitreoretinal lymphomas belong to the family of central nervous system (CNS) lymphomas. The optimal approach for the treatment of isolated primary vitreoretinal lymphoma is unclear because of the lack of large comparative clinical series. Combination of intravitreal and systemic chemotherapy is recommended in many reports. The aim of our retrospective study was to compare the survival rate and prognosis of patients with vitreoretinal lymphoma with and without CNS involvement. METHODS: Twenty patients with vitreoretinal lymphomas were observed between the years 2004and2016, 10 patients with primary vitreoretinal lymphoma and 10 with primary CNS lymphoma. To compare survival rates, we included 53 patients diagnosed with primary CNS lymphoma without vitreoretinal involvement between the years 2002and2011 from our haemato-oncology department. RESULTS: The 5-year survival rate was estimated 71% in patients with vitreoretinal lymphoma in our observation. Significantly longer 5-year overall survival (P˂0.01) was observed in patients with vitreoretinal lymphoma compared with patients with primary CNS lymphoma without vitreoretinal involvement. Progression-free survival was almost equal in both groups of patients with primary vitreoretinal lymphoma and primary CNS lymphoma (P=0.363). The relapse of lymphoma was frequent (50%-60%) with the median time to first relapse of 31 months. Combined treatment (local and systemic) in patients without CNS involvement significantly prolonged progression-free survival in our study (P˂0.05). CONCLUSION: Combined treatment of primary vitreoretinal lymphoma significantly delays the relapse of lymphoma compared with local therapy alone. Intraocular involvement brings significant positive prognostic value when overall survival is compared.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Linfoma Intraocular/tratamiento farmacológico , Recurrencia Local de Neoplasia/fisiopatología , Neoplasias de la Retina/tratamiento farmacológico , Cuerpo Vítreo/efectos de los fármacos , Anciano , Supervivencia sin Enfermedad , Neoplasias del Ojo/tratamiento farmacológico , Neoplasias del Ojo/mortalidad , Neoplasias del Ojo/fisiopatología , Femenino , Citometría de Flujo , Humanos , Linfoma Intraocular/mortalidad , Linfoma Intraocular/fisiopatología , Inyecciones Intravítreas , Masculino , Metotrexato/administración & dosificación , Persona de Mediana Edad , Procarbazina/administración & dosificación , Pronóstico , Neoplasias de la Retina/mortalidad , Neoplasias de la Retina/fisiopatología , Estudios Retrospectivos , Rituximab/administración & dosificación , Tasa de Supervivencia , Factores de Tiempo , Vincristina/administración & dosificación , Agudeza Visual/fisiología , Cuerpo Vítreo/patología
10.
Mult Scler ; 22(6): 770-81, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26362893

RESUMEN

BACKGROUND: The utility of blood-brain barrier (BBB) biomarkers for clinical and magnetic resonance imaging progression in multiple sclerosis (MS) has not been extensively investigated. OBJECTIVES: To determine whether cerebrospinal fluid (CSF) measures of BBB at clinical onset predict radiological and clinical deterioration over 48 months. METHODS: This longitudinal study included 182 patients after first clinical event suggestive of MS treated with weekly intramuscular interferon beta-1a. CSF and serum samples were analyzed for leukocytes, total protein, albumin, immunoglobulins, and oligoclonal bands. Optimal thresholds for the albumin quotient (QAlb) were determined. Mixed-effect model analyses, adjusted for age, gender, and treatment escalation, were used to analyze relationship between CSF measures and disease activity outcomes over 48 months of follow-up. RESULTS: Increased QAlb at clinical onset was associated with enlargement of lateral ventricles (p = .001) and greater whole brain (p = .003), white matter (p < .001), corpus callosum (p < .001), and thalamus (p = .003) volume loss over 48 months. Higher QAlb was associated with higher Expanded Disability Status Scale score over 48 months (p = .002). CONCLUSIONS: Increased QAlb at clinical onset is associated with increased brain atrophy and greater disability in patients after first clinical event suggestive of MS.


Asunto(s)
Albúminas/líquido cefalorraquídeo , Barrera Hematoencefálica , Encéfalo/patología , Progresión de la Enfermedad , Esclerosis Múltiple/líquido cefalorraquídeo , Esclerosis Múltiple/fisiopatología , Índice de Severidad de la Enfermedad , Adulto , Atrofia/patología , Biomarcadores , Encéfalo/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Esclerosis Múltiple/sangre , Albúmina Sérica , Adulto Joven
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