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1.
Cryobiology ; 113: 104588, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37813176

RESUMEN

Chub (reophillic cyprinids) is one of the most sensitive bioindicator fish of environmental changes following anthropogenic activities. The improvement of different biotechnological procedures could help support its conservation and strengthen the natural populations. The aim of this study was to compare the effects of two different hormonal agents (carp pituitary extract and Ovopel™) on various motility parameters (pMOT-%, DAP-µm, VCL µm s-1, VSL-µm s-1, LIN-%, ALH-µm, BCF-Hz) of fresh and cryopreserved/thawed sperm (stored at 4 °C for 6 h). Additionally, we sought to develop a novel, large-scale cryopreservation method for chub sperm, assessing freezing methods (Styrofoam box and a controlled-rate freezer) and different containers (0.5, 5 mL straw and 4 mL cryotube) for sperm cryopreservation. The results of this study indicated no difference between the carp pituitary extract and Ovopel treated groups in either the fresh or frozen/thawed sperm (at 0, 3, 6, hour post thawing, P = 0.4351). In contrast, the quality of the thawed chub sperm was negatively affected after 3 h chilled storage in both hormonal treatments (P = 0.0036, P < 0.0001). When assessing the motility parameters of the sperm between the 5 mL straw and 4 mL cryotube groups cryopreserved in a Styrofoam Box, no difference was observed (P = 0.103). Additionally, sperm loaded in 4 mL cryotubes showed no difference in motility when cryopreserved with either the Styrofoam box or controlled-rate freezer methods (P = 0.109). A similar hatching rate was observed in sperm preserved using the Styrofoam box (35 ± 7 %) and controlled rate freezer (25 ± 9 %) methods (P = 0.300). In a second fertilization trial, hatching rate was similar between control (72 ± 19 %) and cryopreserved (4 mL cryotube and Styrofoam box, 61 ± 5 %) groups. (P = 0.257). Based on our findings and its standard features (less species specific, precise dose calculation), Ovopel can be a good candidate for the stimulation of spermiation in chub sperm prior to cryopreservation. Furthermore, our study presents a novel and applicable method for the large-scale cryopreservation of chub sperm.


Asunto(s)
Carpas , Cyprinidae , Preservación de Semen , Animales , Masculino , Criopreservación/métodos , Semen , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Motilidad Espermática , Espermatozoides , Crioprotectores/farmacología
2.
Mol Pharm ; 14(11): 3927-3934, 2017 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-28972782

RESUMEN

Disadvantageous crystallization phenomenon of amorphous itraconazole (ITR) occurring in the course of dissolution process was investigated in this work. A perfectly amorphous form (solid dispersion) of the drug was generated by the electroblowing method (with vinylpyrrolidone-vinyl acetate copolymer), and the obtained fibers were formulated into tablets. Incomplete dissolution of the tablets was noticed under the circumstances of the standard dissolution test, after which a precipitated material could be filtered. The filtrate consisted of ITR and stearic acid since no magnesium content was detectable in it. In parallel with dissolution, ITR forms an insoluble associate, stabilized by hydrogen bonding, with stearic acid deriving from magnesium stearate. This is why dissolution curves do not have the plateaus at 100%. Two ways are viable to tackle this issue: change the lubricant (with sodium stearyl fumarate >95% dissolution can be accomplished) or alter the polymer in the solid dispersion to a type being able to form hydrogen bonds with ITR (e.g., hydroxypropyl methylcellulose). This work draws attention to one possible phenomenon that can lead to a deterioration of originally good dissolution of an amorphous solid dispersion.


Asunto(s)
Itraconazol/química , Ácidos Esteáricos/química , Cristalización , Composición de Medicamentos , Excipientes/química , Comprimidos/química
3.
Nutr Metab Cardiovasc Dis ; 27(6): 571-580, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28428025

RESUMEN

BACKGROUND AND AIMS: Some crucial associations between obesity-related altered adipokine levels and the main factors of atherosclerotic, atherothrombotic processes are not fully known. We analysed the relationships of classic adipokines, namely leptin, resistin, adiponectin, tumour necrosis factor-alpha (TNF-α), interleukin 6 (IL-6) with the markers of platelet activation, including mean platelet volume (MPV), platelet surface/soluble P-selectin, platelet-derived microparticles (PMPs), the parameters of coagulation abnormalities and common carotid intima-media thickness (IMT) in obese patients with or without atherosclerotic comorbidities in comparison to age- and sex-matched controls. METHODS AND RESULTS: We enrolled 154 obese individuals, including 98 suffering from atherosclerotic concomitant conditions, 56 free of atherosclerotic comorbidities and 62 healthy controls. Plasma levels of leptin, resistin, adiponectin, TNF-α, IL-6, soluble P-selectin, and plasminogen activator inhibitor-1 antigen (PAI-1 ag) were analysed by ELISA. Platelet surface P-selectin and PMPs were measured by flow cytometry. IMT was detected by ultrasonography. Adipokines were closely associated with markers of platelet hyperactivity, hypercoagulability, hypofibrinolysis and IMT. Significant independent associations were found between leptin and platelet count (p < 0.0001), MPV (p = 0.019), PMPs (p < 0.0001), fibrinogen (p = 0.001), factor VIII (FVIII) activity (p = 0.035); adiponectin and PAI-1 ag (p = 0.035); resistin and soluble P-selectin (p = 0.002); TNF-α and PAI-1 ag (p < 0.0001); and IL-6 and fibrinogen (p = 0.011). Finally, leptin (p = 0.0005), adiponectin (p = 0.019), IL-6 (p = 0.001), MPV (p = 0.0003), PMP (p = 0.008), and FVIII activity (p = 0.043) were independent predictors of IMT. CONCLUSION: Overall, we suggest that in obese subjects altered adipokine levels play a key role in common carotid atherosclerosis both directly and through haemostatic parameters.


Asunto(s)
Adipoquinas/sangre , Aterosclerosis/sangre , Plaquetas/metabolismo , Enfermedades de las Arterias Carótidas/sangre , Arteria Carótida Común/diagnóstico por imagen , Grosor Intima-Media Carotídeo , Hemostasis , Obesidad/sangre , Trombosis/sangre , Adulto , Aterosclerosis/diagnóstico por imagen , Aterosclerosis/etiología , Biomarcadores/sangre , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/etiología , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/diagnóstico , Activación Plaquetaria , Factores de Riesgo , Trombosis/diagnóstico por imagen , Trombosis/etiología
4.
Graefes Arch Clin Exp Ophthalmol ; 255(1): 25-30, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27377657

RESUMEN

PURPOSE: Diabetic retinopathy is one of the leading causes of blindness. There are several risk factors, such as the duration of diabetes or glycemic control of the patient; however, several biochemical factors also alter the process. Our aim was to investigate the role of soluble E-selectin in the formation of diabetic retinopathy. PATIENTS AND METHODS: Fifty-seven patients (37 female and 20 male, aged 61.71 ± 12.31 years) and 14 healthy control subjects (ten female and four male, aged 63.06 ± 10.46 years) were enrolled in the study. We measured the soluble E-selectin level in the plasma of patients by ELISA. All patients underwent careful ophthalmological examination, including ophthalmoscopy and color fundus photography, while diabetic retinopathy grading was performed in line with the 2012 classification of the American Academy of Ophthalmology (AAO). RESULTS: The soluble E-selectin level was significantly higher in patients with diabetes compared to controls (32.95 ng/ml vs. 26.55 ng/ml, p = 0.03). Dividing patients into groups by the presence of retinopathy, the E-selectin level was also significantly higher in the retinopathy group (p < 0.05). When we examined diabetic patients by the severity of retinopathy (groups A, B, and C, by the guidelines of the AAO), however, we did not find any significant difference in soluble E-selectin levels, although it tended to be higher in group B. CONCLUSIONS: An elevated E-selectin level can play a role in the development of diabetic retinopathy, but it does not seem to alter disease severity. However, glycemic control and the reduction of cardiovascular risk factors may also alter the level of E-selectin that might play a role in the prevention of diabetic retinopathy.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Retinopatía Diabética/sangre , Selectina E/sangre , Anciano , Biomarcadores/sangre , Diabetes Mellitus Tipo 2/sangre , Retinopatía Diabética/etiología , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo
5.
Opt Lett ; 40(11): 2525-8, 2015 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26030548

RESUMEN

We performed femtosecond laser-induced damage threshold (fs LIDT) measurements with substantially different repetition rate Ti:sapphire laser systems: a 1 kHz regenerative amplifier and a 4.3 MHz long-cavity oscillator. All other pulse parameters are kept the same. Comparative measurements of a dielectric high reflector, a chirped mirror, and metallic mirrors show at least a factor of 2.7 lower fs LIDT at megahertz repetition rates. We attribute this to thermally assisted damage mechanisms supported by complex heat transfer simulations.

6.
Epidemiol Infect ; 142(5): 1019-28, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23866811

RESUMEN

The presence of 10 virulence genes was examined using polymerase chain reaction (PCR) in 365 European O157 and non-O157 Escherichia coli isolates associated with verotoxin production. Strain-specific PCR data were analysed using hierarchical clustering. The resulting dendrogram clearly separated O157 from non-O157 strains. The former clustered typical high-risk seropathotype (SPT) A strains from all regions, including Sweden and Spain, which were homogenous by Cramer's V statistic, and strains with less typical O157 features mostly from Hungary. The non-O157 strains divided into a high-risk SPTB harbouring O26, O111 and O103 strains, a group pathogenic to pigs, and a group with few virulence genes other than for verotoxin. The data demonstrate SPT designation and selected PCR separated verotoxigenic E. coli of high and low risk to humans; although more virulence genes or pulsed-field gel electrophoresis will need to be included to separate high-risk strains further for epidemiological tracing.


Asunto(s)
Escherichia coli O157/clasificación , Escherichia coli O157/patogenicidad , Escherichia coli Shiga-Toxigénica/clasificación , Escherichia coli Shiga-Toxigénica/patogenicidad , Virulencia/genética , Animales , Análisis por Conglomerados , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Escherichia coli O157/genética , Proteínas de Escherichia coli/genética , Europa (Continente)/epidemiología , Humanos , Prevalencia , Ovinos , Escherichia coli Shiga-Toxigénica/genética , Porcinos
7.
Orv Hetil ; 152(40): 1596-608, 2011 Oct 02.
Artículo en Húngaro | MEDLINE | ID: mdl-21945869

RESUMEN

Mutations in BRCA1 and BRCA2 genes account for the majority of hereditary breast and ovarian cancers. Approximately 10% of cases of ovarian cancer are due to germline mutations in BRCA1 and BRCA2. Ovarian cancer associated with BRCA1 and BRCA2 mutations has a distinct histological phenotype. This type of cancer is predominantly of serous or endometrioid histology and is high grade. Patients with BRCA1 or BRCA2 mutations should be offered risk-reducing salpingo-oophorectomy by age 40 years, or when childbearing is complete. Nowadays there are no differences between the treatments provided for sporadic and hereditary ovarian cancer, although there are indications that targeted therapy is effective in women with BRCA1/BRCA2-associated tumors. Retrospective studies reveal a high level of sensitivity to platinum agents in BRCA-associated tumors and initial trials show good efficacy and tolerability for polyADP-ribose polymerase inhibitors in mutation carriers with advanced ovarian cancers. These agents might also potentially be used in chemoprevention. Authors review the current management of hereditary ovarian cancer.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Genes BRCA1 , Genes BRCA2 , Mutación de Línea Germinal , Neoplasias Ováricas/genética , Neoplasias Ováricas/terapia , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Antígeno Ca-125/metabolismo , Metilación de ADN , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/normas , Detección Precoz del Cáncer/tendencias , Trompas Uterinas/cirugía , Femenino , Predisposición Genética a la Enfermedad , Humanos , MicroARNs/metabolismo , Persona de Mediana Edad , Neoplasias Ováricas/clasificación , Neoplasias Ováricas/epidemiología , Neoplasias Ováricas/cirugía , Ovariectomía , Medicina de Precisión/métodos , Medicina de Precisión/normas , Medicina de Precisión/tendencias , Medición de Riesgo , Factores de Riesgo , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo
8.
Acta Haematol ; 123(2): 91-5, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20029173

RESUMEN

In this study, we determined the allele and genotype frequencies of vascular endothelial growth factor (VEGF) G+405C, C-460T, C+936T and C-2578A single nucleotide polymorphisms (SNPs) in 32 patients affected by mantle cell lymphoma (MCL) and 58 healthy controls. Real-time PCR combined with melting curve analysis was used for the determination of SNP alleles. A significant difference in the allele frequency of VEGFC-460T and C+936T SNPs in MCL and healthy cases was not observed. On the contrary, VEGF G+405C and C-2578A SNP allele distribution was significantly lower in the patient group than among normal controls (p = 0.014, p = 0.001). This observation suggests that further investigation is warranted, both in vitro and in a larger series of patients, to further examine the role of VEGF polymorphisms in the pathogenesis of MCL. In addition, the use of quantitative real-time PCR combined with a melting curve analysis method in the detection of the 4 VEGF SNPs may have the potential to replace older and more time-consuming PCR-RFLP methods and bears further investigation.


Asunto(s)
Linfoma de Células del Manto/genética , Polimorfismo de Nucleótido Simple , Factor A de Crecimiento Endotelial Vascular/genética , Adulto , Anciano , Femenino , Frecuencia de los Genes , Humanos , Masculino , Persona de Mediana Edad
9.
Science ; 199(4334): 1199-201, 1978 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-17745606

RESUMEN

In an earlier paper, Khare and Sagan reported the production of a brownish polymeric material from the near-ultraviolet irradiation of simulated jovian atmospheres with a low hydrogen abundance. Examination of this product indicates that hydrogen sulfide is the initial photon acceptor; the powder resulting after extraction with benzene is 84 percent sulfur, largely S(8). In results reported here, the remaining 16 percent was pyrolyzed and then examined by gas chromatography-mass spectrometry. Pyrolysis at 450 degrees C yielded a series of alkanes, alkenes, C(3)-alkylbenzenes, aromatics, thiophenes, alkylthiophenes, alkylmercaptans, alkyldisulfides, together with the nitrogenous compounds hydrogen cyanide, methyl cyanide, alkylisothiocyanates, acrylonitrile, and allylisothiocyanates. Some of these compounds might be sought on Jupiter and Saturn and their satellites by remote infrared and ultraviolet spectroscopy and directly by entry probes.

10.
Science ; 161(3845): 1005-8, 1968 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-17812798

RESUMEN

Spheroidal and cupshaped, carbonaceous alga-like bodies, as well as filamentous structures and amorphous carbonaceous matter occur in sedimentary rocks of the Onverwacht Series (Swaziland System) in South Africa. The Onverwacht sediments are older than 3.2 eons, and they are probably the oldest, littlealtered sedimentary rocks on Earth. The basal Onverwacht sediments lie approximately 10,000 meters stratigraphically below the Fig Tree sedimentary rocks, from which similar organic microstructures have been interpreted as alga-like microfossils. The Onverwacht spheroids and filaments are best preserved in black, carbonrich cherts and siliceous argillites interlayered with thick sequences of lavas. These lifelike forms and the associated carbonaceous substances are probably biological in origin. If so, the origins of unicellular life on Earth are buried in older rocks now obliterated by igneous and metamorphic events.

11.
Science ; 167(3918): 770-3, 1970 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-5410553

RESUMEN

Lunar fines and a chip from inside a rock pyrolyzed in helium at 700 degrees C gave methane, other gases, and aromatic hydrocarbons. Benzene/methanol extracts of fines yielded traces of high molecular weight alkanes and sulfur. Traces of glycine, alanine, ethanolamine, and urea were found in aqueous extracts. Biological controls and a terrestrial rock, dunite, subjected to exhaust from the lunar module descent engine showed a different amino acid distribution. Interpretation of the origin of the carbon compounds requires extreme care, because of possible contamination acquired during initial sample processing.


Asunto(s)
Aminoácidos/análisis , Medio Ambiente Extraterrestre , Geología , Hidrocarburos/análisis , Fenómenos Astronómicos , Astronomía , Cromatografía de Gases , Cromatografía por Intercambio Iónico , Fenómenos Geológicos , Microscopía Electrónica de Rastreo , Vuelo Espacial
12.
Horm Metab Res ; 41(5): 374-80, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19214941

RESUMEN

The efficacy and safety of the new drug, BGP-15, were compared with placebo in insulin-resistant patients in a 28-day dose-ranging study. Forty-seven nondiabetic patients with impaired glucose tolerance were randomly assigned to 4 weeks of treatment with 200 or 400 mg of BGP-15 or placebo. Insulin resistance was determined by hyperinsulinemic euglycemic clamp technique and homeostasis model assessment method, and beta-cell function was measured by intravenous glucose tolerance test. Each BGP-15 dose significantly increased whole body insulin sensitivity (M-1, p=0.032), total body glucose utilization (M-2, p=0.035), muscle tissue glucose utilization (M-3, p=0.040), and fat-free body mass glucose utilization (M-4, p=0.038) compared to baseline and placebo. No adverse drug effects were observed during treatment. BGP-15 at 200 or 400 mg significantly improved insulin sensitivity in insulin-resistant, nondiabetic patients during treatment compared to placebo and was safe and well-tolerated. This was the first clinical study demonstrating the insulin-sensitizing effect of a molecule, which is considered as a co-inducer of heat shock proteins.


Asunto(s)
Intolerancia a la Glucosa/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Resistencia a la Insulina , Insulina/metabolismo , Oximas/administración & dosificación , Piperidinas/administración & dosificación , Adulto , Método Doble Ciego , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Femenino , Glucosa/metabolismo , Intolerancia a la Glucosa/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Placebos , Adulto Joven
17.
18.
19.
Oral Oncol ; 44(3): 227-35, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17604679

RESUMEN

Some oral squamous cell carcinomas (OSCCs) overexpress epidermal growth factor receptor (EGFR) but little is known about the receptor system overall during oral carcinogenesis. We studied all four ERBB receptors (EGFR, ERBB2-4) in developing (n=2), normal (n=7), dysplastic (n=23) and malignant (n=26) oral epithelia by means of immunohistochemistry. The investigations were supplemented by conducting reverse transcription-polymerase chain reactions in relation to 13 OSCC samples. All four ERBB receptors were detected in developing oral epithelium and, to a lesser degree, in mature oral epithelium. An increase in EGFR immunoreactivity was seen in 61% and 54% of dysplasias and OSCCs, respectively. The corresponding percentages for ERBB2 were 48 and 12, for ERBB3 48 and 43. ERBB4 nuclear staining was increased in 30% of dysplasias and 26% of OSCCs. Changes in ERBB receptor mRNA levels were not statistically significant. The results show that ERBB receptor profiles are specific to each tumour. Increased nuclear translocation of ERBB4 in some OSCCs may alter transcription of target genes and be associated with cancer progression. This information may be useful for clinicians as EGFR inhibitors are becoming treatment options in modern oncology.


Asunto(s)
Carcinoma de Células Escamosas/metabolismo , Mucosa Bucal/metabolismo , Neoplasias de la Boca/metabolismo , Proteínas Tirosina Quinasas Receptoras/análisis , Adulto , Anciano , Carcinoma de Células Escamosas/genética , Receptores ErbB/análisis , Genes erbB , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Mucosa Bucal/embriología , Mucosa Bucal/patología , Neoplasias de la Boca/genética , Ploidias , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/patología , ARN Mensajero/análisis , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Receptor ErbB-2/análisis , Receptor ErbB-3/análisis , Receptor ErbB-4 , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Coloración y Etiquetado , Estadísticas no Paramétricas
20.
Rev Sci Instrum ; 89(5): 056105, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29864798

RESUMEN

A neutron polarizer using four successive reflections on m = 2.5 supermirrors was built and installed at the GINA neutron reflectometer at the Budapest Neutron Centre. This simple setup exhibits 99.6% polarizing efficiency with 80% transmitted intensity of the selected polarization state. Due to the geometry, the higher harmonics in the incident beam are filtered out, while the optical axis of the beam remains intact for easy mounting and dismounting the device in an existing experimental setup.

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