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1.
Neoplasma ; 67(1): 164-170, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31777257

RESUMO

The differential diagnosis of well-differentiated tumors of follicular cell origin remains the most problematic task in thyroid pathology. Specific morphologic criteria (capsular and/or vascular invasion, nuclear characteristics) are crucial in the diagnosis of these neoplasms. However, the assessment of malignant features is inconclusive in some cases. Moreover, oncocytic thyroid tumors remain controversial in a respect to their pathobiology, behavior and management. Therefore, the useful diagnostic/prognostic thyroid markers are awaited. The aim of our study was to evaluate the expression of galectin-3 and thyroid peroxidase (TPO) in benign and malignant thyroid tumors of follicular cell origin. A total of 186 archival thyroid samples including 38 non-oncocytic follicular adenomas, 53 oncocytic (Hürthle cell) adenomas, 6 non-oncocytic follicular carcinomas, 23 oncocytic (Hürthle cell) carcinomas, 43 non-oncocytic papillary carcinomas, and 23 oncocytic papillary carcinomas were analyzed for galectin-3 and TPO expression by immunohistochemistry. Both types of papillary carcinomas showed significant upregulation of galectin-3 in comparison with the other tumor types, likewise, significant differences in galectin-3 expression were discovered between non-oncocytic and oncocytic variants of studied tumors excluding follicular carcinoma. Significant lowering of TPO was revealed in oncocytic adenomas and papillary carcinomas. In conclusion, the combined use of galectin-3 and TPO markers could help to improve the differential diagnosis of thyroid tumors. Differences in the galectin-3 and TPO expression between some oncocytic and non-oncocytic tumors support their separation in the latest WHO classification of thyroid tumors.


Assuntos
Autoantígenos/genética , Galectina 3/genética , Iodeto Peroxidase/genética , Proteínas de Ligação ao Ferro/genética , Neoplasias da Glândula Tireoide/diagnóstico , Biomarcadores Tumorais/genética , Proteínas Sanguíneas , Diagnóstico Diferencial , Galectinas , Humanos , Neoplasias da Glândula Tireoide/classificação
2.
Rozhl Chir ; 98(4): 159-166, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31159549

RESUMO

INTRODUCTION: Future liver remnant volume (FLRV) is a crucial factor impacting resectability of colorectal liver metastases (CLM). In case of low FLRV, augmentation can be done by performing portal vein embolization (PVE). However, there is a risk of progression of CLM between PVE and resection. Intraportal application of autologous hematopoietic stem cells (HSC) is a possibility to accelerate the growth of FLRV. The effect of thus applied SC on CLM progression still remains unclear, though. METHODS: 63 patients underwent PVE between 2003 and 2015. In 20 patients a product with HSC was applied intraportally on the first day after PVE (PVE HSC group). HSC were gained from peripheral blood (10 patients) or bone marrow (10 patients). FLRV and volume of liver metastases (VLM) were evaluated by CT volumetry. The gained data were statistically evaluated in relation to the disease free interval (DFI), overall survival (OS), achievement of CLM resectability and progression of extrahepatic metastases. We compared the PVE HSC group with the group of patient undergoing simple PVE. RESULTS: No significant difference in FLRV and VLM growth was observed between the study groups. The percentage of exploratory laparotomies was smaller in the group with PVE and HSC application. Patients with simple PVE had a significantly higher incidence of extrahepatic metastases during follow up. We did not observe any significant differences in DFI and OS between the groups. CONCLUSION: HSC application did not accelerate CLM growth in comparison with PVE alone. PVE and HSC application had a higher percentage of patients undergoing liver resection and a lower incidence of extrahepatic metastases.


Assuntos
Neoplasias Colorretais , Embolização Terapêutica , Neoplasias Hepáticas , Células-Tronco , Neoplasias Colorretais/patologia , Hepatectomia , Humanos , Neoplasias Hepáticas/secundário , Veia Porta
3.
Ultrason Sonochem ; 14(1): 19-28, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16545594

RESUMO

The intensity distribution of the ultrasonic energy is, after the frequency, the most significant parameter to characterize ultrasonic fields in any sonochemical experiment. Whereas in the case of low intensity ultrasound the measurement of intensity and its distribution is well solved, in the case of high intensity (when cavitation takes place) the measurement is much more complicated. That is why the predicting the acoustic pressure distribution within the cell is desirable. A numerical solution of the wave equation gave the distribution of intensity within the cell. The calculations together with experimental verification have shown that the whole reactor behaves like a resonator and the energy distribution depends strongly on its shape. The agreement between computational simulations and experiments allowed optimisation of the shape of the sonochemical reactor. The optimal geometry resulted in a strong increase in intensity along a large part of the cell. The advantages of such optimised geometry are (i) the ultrasonic power necessary for obtaining cavitation is low; (ii) low power delivered to the system results in only weak heating, consequently, no cooling is necessary and (iii) the "active volume" is large, i.e. the fraction of the reactor volume with high intensity is large and is not limited to a vicinity close to the horn tip.


Assuntos
Desenho Assistido por Computador , Modelos Teóricos , Radiometria/métodos , Sonicação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Doses de Radiação
4.
Ceska Slov Farm ; 49(4): 185-9, 2000 Jul.
Artigo em Tcheco | MEDLINE | ID: mdl-10953469

RESUMO

The paper presents an introductory physicochemical study dealing with the preparation of atelocollagen felt saturated with local anesthetics, with the modelling of the release of the anesthetic from the collagen matrix in vitro, and with the checking of the corresponding analytical procedures (dc-polarography and UV-VIS spectrophotometry) for the determination of cinchocaine. The study is supplemented with experiments in vivo that confirm the usability of the new material for the depot formation of local anesthetics.


Assuntos
Anestésicos Locais/química , Colágeno , Preparações de Ação Retardada/química , Dibucaína/química , Veículos Farmacêuticos , Química Farmacêutica , Polarografia , Espectrofotometria
5.
J Agric Food Chem ; 47(9): 3879-85, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10552738

RESUMO

Metamitron (1) does not undergo hydrolysis at pH 1-8 and up to 5 M H(2)SO(4). The product of its two-electron reduction, 1, 6-dihydrometamitron (2), on the other hand, undergoes at pH <3 relatively fast hydrolysis. The dependence of the measured rate constant on acidity indicates that the completely protonated form (AH(2)(2+)) predominating in strongly acidic media undergoes hydrolysis slower than the species bearing one less proton (AH(+)). The latter most reactive species is present in highest concentration in solutions of pH between 0 and 2. This species is protonated on the 2,3-azomethine bond and yields as final products 2-hydrazino-2-phenylacetic acid (4) and acethydrazide (5). Kinetic, polarographic, and spectrophotometric measurements indicated for the first dissociation an average value pK(a) = -0.8, for the second pK(a) = 0.95. These observations together with the easy reduction of the 1,6-bond in metamitron (1) indicate that in nature the cleavage of metamitron may be preceded by its reduction to 1, 6-dihydrometamitron (2), which is then hydrolyzed. Thus, anaerobic, reductive conditions are likely preferable for the total microbial degradation of metamitron.


Assuntos
Herbicidas/química , Triazinas/química , Concentração de Íons de Hidrogênio , Hidrólise , Estrutura Molecular , Oxirredução
6.
Folia Microbiol (Praha) ; 44(3): 271-5, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10664882

RESUMO

In Bacillus megaterium, a temperature that suppresses sporulation (43 degrees C) only slightly exceeds both the optimum growth temperature and the temperature still permitting sporulation (40-41 degrees C). Here we show that, when cells grown at 35 degrees C and transferred to a sporulation medium, were subjected to shifts between 35 degrees C and the sporulation suppressing temperature (SST, 43 degrees C), their development and proteolytic activities were deeply affected. During the reversible sporulation phase that took place at 35 degrees C for 2-3 h (T2-T3), the cells developed forespores and their protein turnover was characterized by degradation of short-lived proteins and proteins made accessible to the proteolytic attack because of starvation. During the following irreversible sporulation phase refractile heat-resistant spores appeared at T4-T5. Protein turnover rate increased again after T2 and up to T8 60-70% prelabelled proteins were degraded. The SST suppressed sporulation at its beginning; at T3 no asymmetric septa were observed and the amount of heat-resistant spores at T8 was by 4-5 orders lower than at 35 degrees C. However, the cells remained viable and were able to sporulate when transferred to a lower temperature. Protein degradation was increased up to T3 but then its velocity sharply dropped and the amount of degraded protein at T8 corresponded to slightly more than one-half of that found at 35 degrees C. The cytoplasmic proteolytic activity was enhanced but the activity in the membrane fraction was decreased. When a temperature shift to SST was applied at the beginning of the irreversible sporulation phase (T2.5), the sporulation process was impaired. A portion of forespores lyzed, the others were able to complete their development but most spores were not heat-resistant and their coats showed defects. Protein degradation increased again because an effective proteolytic system was developed during the reversible sporulation phase but the amount of degraded protein was slightly lower than at 35 degrees C. A later (T4) shift to SST had no effect on the sporulation process.


Assuntos
Bacillus megaterium/metabolismo , Proteínas de Bactérias/metabolismo , Bacillus megaterium/ultraestrutura , Endopeptidases/metabolismo , Cinética , Esporos Bacterianos/metabolismo , Esporos Bacterianos/ultraestrutura , Temperatura
7.
Biochem Mol Biol Int ; 39(6): 1185-92, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8876972

RESUMO

Asporogenic mutant blocked in the 0-II sporulation stage degraded pulse-labelled proteins in the sporulation medium at the same rate as the parental strain for the first two hours. The degraded fraction was mostly composed of intrinsically short-lived proteins which were degraded even after enriching the medium with amino acids and growth resumption. Proteins accessible to degradation because of nutritional shift down formed a lesser proportion of this fraction. The acceleration of protein turnover in the parent strain during the irreversible sporulation phase was not developed in the mutant. A first order kinetic model of protein degradation was used for parameter estimation. Ca(2+)-dependent intracellular serine proteinase was synthesized in an inactive form, which was activated by increasing Ca2+ concentration to 30 mM.


Assuntos
Bacillus megaterium/metabolismo , Proteínas de Bactérias/metabolismo , Esporos Bacterianos/metabolismo , Bacillus megaterium/genética , Bacillus megaterium/ultraestrutura , Cálcio/metabolismo , Cinética , Mutação , Serina Endopeptidases/metabolismo , Esporos Bacterianos/genética
8.
Folia Microbiol (Praha) ; 35(4): 291-7, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2262170

RESUMO

The mean lengths of G1, S, G2 and M phases of the cell cycle were determined on the basis of the population distribution of Candida utilis grown in a continuous culture under steady-state conditions by using an original mathematical method. The length of the G2 phase was proportional to that of G1; the length of M was effectively independent of the growth rate. The length of S was proportional to the mean number of mitochondria in the cell.


Assuntos
Candida/citologia , Ciclo Celular , Candida/genética , Candida/crescimento & desenvolvimento , DNA Fúngico/análise , DNA Mitocondrial/análise , Interfase , Probabilidade , Fase S
9.
Folia Biol (Praha) ; 36(5): 231-5, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2276399

RESUMO

During in vitro incubation, the pulmonary and thymic tissue of mice released a colony stimulating factor (CSF) supporting the development of colonies of granulocytes and macrophages from bone marrow progenitors. Cardiac, splenic, renal and bone marrow tissues were not active. The dysgenetic thymus of nude mice was a very potent source of CSF during in vitro incubation.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/isolamento & purificação , Timo/metabolismo , Envelhecimento , Animais , Células Cultivadas , Meios de Cultura , Pulmão/metabolismo , Pulmão/ultraestrutura , Camundongos , Camundongos Endogâmicos , Camundongos Nus , Técnicas de Cultura de Órgãos , Timo/ultraestrutura
10.
J Basic Microbiol ; 27(9): 521-8, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-3454375

RESUMO

A thy- tetracycline-resistant mutant of Streptomyces granaticolor was prepared by mutagenesis of the parental strain ETH 7437. The mutant exhibits a different morphology and an overproduction of granaticins. The ability to form an aerial mycelium and spores has been lost. The mutant cells have a round or an atypical shape and a thick cell wall, the membraneous system is enlarged by numerous mesosomes. Division septa are formed rarely. The mutant is more sensitive to both low and high temperature than the parental strain. The altered features are stably maintained for many generations. Ribosomal proteins of the mutant do not differ substantially from those of the original strain indicating that the mutant phenotype is not due to an alteration at the translational level.


Assuntos
Antibióticos Antineoplásicos/metabolismo , Streptomyces/metabolismo , Cromatografia em Camada Fina , Eletroforese em Gel de Poliacrilamida , Fermentação , Microscopia Eletrônica , Mutação , Naftoquinonas/metabolismo , Proteínas Ribossômicas/análise , Streptomyces/genética , Streptomyces/crescimento & desenvolvimento , Streptomyces/ultraestrutura , Temperatura , Resistência a Tetraciclina
11.
Virology ; 140(2): 360-3, 1985 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-2982237

RESUMO

Three new phage-like particles (CG1, CG2, and CGK1) were isolated from Corynebacterium glutamicum CBII. Particles CG1 and CG2 are DNA phages with long, noncontractile tails, CGK1 is a killer particle according to electron microscopy. A heat-stable low-molecular-weight bacteriocidal substance affecting various coryneform bacteria was observed to be joined to the killer particle CGK1.


Assuntos
Bacteriófagos/isolamento & purificação , Corynebacterium , Bacteriocinas/isolamento & purificação , Bacteriófagos/ultraestrutura , Corynebacterium/ultraestrutura , Enzimas de Restrição do DNA , DNA Viral/isolamento & purificação , Mitomicina , Mitomicinas/farmacologia , Ativação Viral/efeitos dos fármacos
12.
Folia Microbiol (Praha) ; 30(2): 97-100, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3922858

RESUMO

Protoplasts of Bacillus subtilis 168 trpC2 str and cells of Escherichia coli SK 1590 after treatment with calcium chloride were transformed to tetracycline resistance with the recombinant plasmid pUN82 entrapped in the reverse phase evaporation liposomes. Frequency of transfer was 4 X 10(-4)% in B. subtilis and 8 X 10(-6)% in E. coli.


Assuntos
Bacillus subtilis/genética , Cloreto de Cálcio/farmacologia , Escherichia coli/genética , Lipossomos , Fosfatidilcolinas , Fosfatidilgliceróis , Protoplastos/metabolismo , Fatores R , Resistência Microbiana a Medicamentos , Escherichia coli/efeitos dos fármacos , Vetores Genéticos , Tetraciclina/farmacologia
16.
Folia Microbiol (Praha) ; 21(2): 117-24, 1976.
Artigo em Inglês | MEDLINE | ID: mdl-181299

RESUMO

Subcellular fractions containing plasma membranes with bound DNA and associated proteins were isolated from two different cultures of Bacillus subtilis 168 growing exponentially at different rates. Differences in the contents of individual between the dissociated complexes, established electrophoretically, can be explained by dynamic binding of the proteins to DNA, resulting in a control of DNA, resulting in a control of DNA replication. Electron microphotographs of isolated complexes display, in addition to unit membranes, associated filamentous structures in different arragement. Patterns obtained after treating the complexes with nucleases suggest a polydeoxyribonucleotide character of the filamentous structures.


Assuntos
Bacillus subtilis/análise , Proteínas de Bactérias/análise , DNA Bacteriano/análise , Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Membrana Celular/análise , Membrana Celular/metabolismo , DNA Bacteriano/metabolismo , Desoxirribonucleases/metabolismo , Diester Fosfórico Hidrolases/metabolismo , Protoplastos/análise , Ribonucleases/metabolismo , Frações Subcelulares/análise
18.
J Bacteriol ; 120(3): 1401-8, 1974 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-4436258

RESUMO

Criteria for morphogenetic and ultrastructural distinction between conidia and chlamydospores of a submerged culture of Claviceps purpurea (Fr.) Tul. are described. Both the hyphae of the sphacelia (asexual) stage and the conidia contained granular cytoplasm. Cytoplasmic invaginations in vacuoles were transformed to electron-opaque bodies and disintegrated prior to germination. The budding of conidia had basipetal succession. The chlamydospores were formed by rounding up the terminal cells of filamentous hyphae. Homogeneous nonvacuolized cytoplasm with lipid droplets and lipid-forming bodies was characteristic of young chlamydospores. Cristate mitochondria did not appear in the chlamydospores before the alkaloid production phase. Simultaneously a specific organelle in the chlamydospores, a dense body, appeared to absorb intracellular lipids and form large deposits of phospholipid material. No germination of chlamydospores was observed. The ultrastructural pattern described for chlamydospores was also observed in hyphae with reduced proliferation during the alkaloid production phase.


Assuntos
Claviceps/ultraestrutura , Alcaloides de Claviceps/biossíntese , Morfogênese , Membrana Celular/ultraestrutura , Núcleo Celular/ultraestrutura , Claviceps/crescimento & desenvolvimento , Citoplasma/ultraestrutura , Lipídeos , Microscopia Eletrônica , Mitocôndrias/ultraestrutura , Organoides/ultraestrutura , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/ultraestrutura , Vacúolos/ultraestrutura
19.
J Bacteriol ; 118(1): 285-94, 1974 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-4362461

RESUMO

Morphological characteristics of two types of elements in the submerged mycelium of Claviceps paspali are described. Distribution of polysaccharides in the cell wall and cytoplasm was cytochemically determined at the ultrastructural level. Polysaccharide deposition into the cell walls was proportional to the increase in the alkaloid yield. In the cytoplasm, on the other hand, the presence of polysaccharide grains indicated an absence of alkaloid synthesis.


Assuntos
Alcaloides/biossíntese , Claviceps/citologia , Polissacarídeos/isolamento & purificação , Alcaloides/análise , Parede Celular/análise , Claviceps/análise , Claviceps/crescimento & desenvolvimento , Claviceps/metabolismo , Citoplasma/análise , Grânulos Citoplasmáticos , Fermentação , Glicogênio , Histocitoquímica , Dietilamida do Ácido Lisérgico/análise , Microscopia Eletrônica , Ácido Periódico , Esporos Fúngicos/análise , Esporos Fúngicos/citologia , Esporos Fúngicos/crescimento & desenvolvimento
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