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1.
Ann Oncol ; 30(8): 1298-1303, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31192355

RESUMO

BACKGROUND: This trial evaluated whether preoperative short-course radiotherapy and consolidation chemotherapy (CCT) were superior to chemoradiation in rectal cancers with clinical (c)T4 or fixed cT3. Previously, we reported early results showing no differences in the radical surgery rate (primary end point). In the short-course/CCT group, we observed lower acute toxicity of preoperative treatment and better overall survival (OS). We updated results to determine whether the benefit in OS was sustained and to evaluate late complications. PATIENTS AND METHODS: Patients with cT4 or fixed cT3 rectal cancer were randomized either to preoperative 5 × 5 Gy and three cycles of FOLFOX4 or to chemoradiation (50.4 Gy with bolus 5-Fu, leucovorin and oxaliplatin). RESULTS: Patients (N = 515) were eligible for analysis, 261 in the short-course/CCT group and 254 in the chemoradiation group. The median follow-up was 7.0 years. The difference in OS was insignificant [hazard ratio (HR) 0.90; 95% confidence interval (CI) 0.70-1.15; P = 0.38). However, the difference in early OS favouring short-course/CCT previously reported was observed again, being 9% at 3 years (95% CI 0.5% to 17%). This difference disappeared later; at 8 years OS was 49% in both groups. There was no difference in disease-free survival (HR 0.95; 95% CI 0.75-1.19; P = 0.65) at 8 years 43% versus 41% in the short-course/CCT group versus the chemoradiation group, respectively. The corresponding values for cumulative incidences of local failure and distant metastases did not differ and were HR = 1.08, 95% CI 0.70-1.23, P = 0.60, 35% versus 32% and HR = 1.10, 95% CI 0.68-1.23, P = 0.54, 36% versus 34%, respectively. The rate of late complications was similar (P = 0.66), grade 3+ being 11% versus 9% in the short-course/CCT group versus the chemoradiation group, respectively. CONCLUSION: The superiority of preoperative short-course/CCT over chemoradiation was not demonstrated. CLINICAL TRIAL NUMBER: The trial is registered as ClinicalTrials.gov number NCT00833131.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Fracionamento da Dose de Radiação , Terapia Neoadjuvante/métodos , Recidiva Local de Neoplasia/epidemiologia , Neoplasias Retais/terapia , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia/efeitos adversos , Quimiorradioterapia/métodos , Quimioterapia de Consolidação/efeitos adversos , Quimioterapia de Consolidação/métodos , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Seguimentos , Humanos , Incidência , Leucovorina/administração & dosagem , Leucovorina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/efeitos adversos , Recidiva Local de Neoplasia/prevenção & controle , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Polônia/epidemiologia , Protectomia , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Reto/efeitos dos fármacos , Reto/patologia , Reto/efeitos da radiação , Reto/cirurgia , Fatores de Tempo , Adulto Jovem
2.
Pol J Vet Sci ; 21(4): 823-825, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30605294

RESUMO

This study analysed the influence of montelukast (MON; 10-8 - 10-4 M), a cysteinyl leukotriene receptor 1 (CysLTR1) antagonist, on the contractility of the porcine uterine smooth muscle in the luteal phase of the oesterous cycle (n=8) and in early pregnancy (n=8). Stimulation of uterine strips in the luteal phase with MON has been shown to significantly reduce the amplitude of con- tractions, but not to affect the tension or frequency of contractions. A statistically significant tension increase and decrease in the frequency and amplitude of contractions was observed in pigs in early pregnancy. This suggests that MON has a different effect on the parameters under study in cyclic and pregnant pigs.


Assuntos
Acetatos/farmacologia , Antagonistas de Leucotrienos/farmacologia , Fase Luteal/fisiologia , Prenhez , Quinolinas/farmacologia , Suínos/fisiologia , Contração Uterina/efeitos dos fármacos , Animais , Ciclopropanos , Feminino , Gravidez , Sulfetos
3.
Artigo em Inglês | MEDLINE | ID: mdl-30906172

RESUMO

Recently, significant improvement in the strain tolerance of Bi-2223 conductor has been achieved by lamination with high strength nickel alloy. The conductor, supplied by Sumitomo Electric and designated Type HT-NX, is now commercially available in lengths sufficient for manufacture of high-homogeneity solenoids. A program to fully exploit the improved conductor properties is now underway at the National High Magnetic Field Laboratory (NHMFL). Five coils are being made, the last of which is to demonstrate an NMR measurement approaching 1 GHz and 1 ppm over 10 mm volume. In so doing, we expect to demonstrate critical current fraction, and strain similar to that expected in 30 T NMR magnets. The coils will be tested inside an existing 16 Tesla large-bore background magnet at the NHMFL. The design of the NMR demonstration coil is presented first, with expected values for field, homogeneity and strain given. A technology development program is then outlined, which includes fabrication of four test coils to test various design features, develop fabrication tooling and train personnel.

4.
Pol J Vet Sci ; 20(1): 111-121, 2017 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-28525334

RESUMO

This study analysed the relaxant properties of salbutamol (ß2-adrenoceptors agonist) and BRL 37344 (ß3-adrenoceptors agonist) regarding the contractility of porcine myometrium on days 10-14 of the oestrous cycle (cyclic group; n = 10) and on days 3-5 of pregnancy (early pregnant group; n = 6). The activity of myometrial strips (tension, frequency and amplitude) was recorded under isometric conditions using force transducers. The contractility was assessed further following the administration of increasing concentrations of the agonists (10-9-10-4 M), both with and without ß-adrenoceptor antagonists (butaxamine - a selective ß2- adrenoceptor antagonist, propranolol- a non-selective ß1- and ß2-adrenoceptor antagonist and bupranolol - a non-selective ß1-, ß2- and ß3-adrenoceptor antagonist) at a concentration of 10-4 M. Although neither salbutamol nor BRL 37344 caused changes in the tension, at the highest concentrations they decreased the frequency and amplitude of contractions. These changes were more evident after salbutamol treatment and in the early pregnant group. Antagonists given alone did not cause changes in the parameters examined but changed some activity of the agonists. Butoxamine reduced the decrease in frequency and amplitude induced by salbutamol and produced a decrease in the tension after BRL 37344 treatment in the early pregnant group. Propranolol reduced the decrease in frequency and amplitude induced by salbutamol in both examined groups and did not cause significant changes in BRL 37344 activity. The administration of bupranolol before salbutamol treatment caused an increase in the tension and reduced the decrease in the frequency in the cyclic group. Moreover, bupranolol eliminated a decrease in frequency and induced an increase in amplitude caused by BRL 37344 in both groups and these changes were more evident in the early pregnant group. The data indicates that both ß2- and ß3-adenoreceptors are involved in the regulation of the contractility in both groups, but the changes after agonists and antagonists treatment are more evident in the early pregnant myometrium.


Assuntos
Agonistas de Receptores Adrenérgicos beta 2/farmacologia , Agonistas de Receptores Adrenérgicos beta 3/farmacologia , Corpo Lúteo/efeitos dos fármacos , Miométrio/fisiologia , Prenhez , Suínos/fisiologia , Albuterol/farmacocinética , Albuterol/farmacologia , Animais , Bupranolol/farmacocinética , Bupranolol/farmacologia , Butoxamina/farmacocinética , Butoxamina/farmacologia , Corpo Lúteo/fisiologia , Interações Medicamentosas , Etanolaminas/farmacocinética , Etanolaminas/farmacologia , Feminino , Gravidez , Prenhez/fisiologia , Contração Uterina/efeitos dos fármacos
5.
Pol J Vet Sci ; 20(3): 485-490, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-29166277

RESUMO

The present in vitro study investigated the influence of doxazosin on the contractility of the urinary bladder in female pigs with experimentally induced cystitis. Fifteen juvenile female piglets (18-20 kg body weight) were randomly assigned into three groups (n=5 animals each): i) control (clinically healthy animals, without doxazosin treatment), ii) animals with induced inflammation of the urinary bladder, but without doxazosin treatment (experimental group I) and iii) animals with inflamed bladder, treated orally with doxazosin (0.1 mg/kg body weight for 30 days; experimental group II). Thereafter, the pigs were sacrificed and strips of the bladder trigone were suspended in organ baths. The tension and amplitude of the smooth muscles was measured before and after exposition to 5-hydroxytryptamine (5-HT; 10-6-10-4 M), acetylocholine (ACh; 10-5-10-3 M) and norepinephrine (NE; 10-9-10-7 M). 5-HT caused an increase in the tension of contractions in all the groups and the amplitude in the experimental groups, however, the effect was higher in the experimental group I than in group II as compared to that found in the pre-treatment period. ACh caused an increase in the tension in the control group and a decrease in the amplitude in both experimental groups; these changes significantly differed between the control and doxazosin-treated group. NE caused a decrease in the tension in both experimental groups and amplitude in all the groups, however, the effect was most strongly expressed in doxazosine-treated group. The present study has revealed that long-term administration of doxazosin causes a desensitization of the detrusor smooth muscle to in vitro applied mediators in the autonomic nervous system.


Assuntos
Cistite/veterinária , Doxazossina/farmacologia , Contração Muscular/efeitos dos fármacos , Doenças dos Suínos/induzido quimicamente , Acetilcolina/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Animais , Agonistas Colinérgicos/farmacologia , Cistite/induzido quimicamente , Feminino , Músculo Liso/efeitos dos fármacos , Norepinefrina/farmacologia , Distribuição Aleatória , Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Suínos , Doenças dos Suínos/tratamento farmacológico , Simpatomiméticos/farmacologia , Bexiga Urinária/efeitos dos fármacos
6.
Pol J Vet Sci ; 17(3): 527-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25286666

RESUMO

In the present study influence of doxazosin on the porcine urinary bladder contractility has been examined. Immature pigs were treated for 30 days with: a) doxazosin (n = 5) per os at a dose of 0.1 mg/kg b.w. or b) placebo (n = 5; control group). Thereafter, animals were sacrificed and urinary bladder strips from the trigone were suspended in organ baths. The tension of the smooth musce was measured before and after exposition to acetylocholine (ACh; 10(-5) - 10(-3) M), norepinephrine (NE; 10(-9) - 10(-7) M) and 5-hydroxytryptamine (5-HT; 10(-7) - 10(-5) M). Both the ACh and 5-HT at the highest doses significantly increased the contractility in each group, but this response was weaker in doxazosin-treated animals. NE caused relaxation in both groups, but the effect was weaker in doxazosine-treated group. The results of our study have shown that long-term administration of doxazosin caused a desensitization of the detrusor smooth muscle for in vitro applied mediators of the autonomic nervous systems.


Assuntos
Antagonistas de Receptores Adrenérgicos alfa 1/farmacologia , Doxazossina/farmacologia , Contração Muscular/efeitos dos fármacos , Suínos , Bexiga Urinária/efeitos dos fármacos , Animais , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Bexiga Urinária/fisiologia
7.
Nature ; 450(7170): 633-6, 2007 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-18046394

RESUMO

Venus is completely covered by a thick cloud layer, of which the upper part is composed of sulphuric acid and some unknown aerosols. The cloud tops are in fast retrograde rotation (super-rotation), but the factors responsible for this super-rotation are unknown. Here we report observations of Venus with the Venus Monitoring Camera on board the Venus Express spacecraft. We investigate both global and small-scale properties of the clouds, their temporal and latitudinal variations, and derive wind velocities. The southern polar region is highly variable and can change dramatically on timescales as short as one day, perhaps arising from the injection of SO2 into the mesosphere. The convective cells in the vicinity of the subsolar point are much smaller than previously inferred, which we interpret as indicating that they are confined to the upper cloud layer, contrary to previous conclusions, but consistent with more recent study.

8.
Pol J Vet Sci ; 15(4): 635-43, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23390752

RESUMO

Recent studies show that a representative of phospholipids, namely lysophosphatidic acid (LPA) and its receptors (LPA1.3) play a significant role in the reproductive processes, i. a, in the modulation of the uterine contractility. The participation of LPA3 in the reproductive processes has been revealed in mice and has not been studied in gilts. Therefore, in the present study we investigated the role/action of LPA and its receptors LPA1, LPA2 and LPA3 on the contraction activity in the porcine uterus. The study was conducted on an experimental model in which the pig uterus consisted of the one whole uterine horn and a part of the second horn, both connected with the uterine corpus. Uterine strips consisting of the endometrium with the myometrium (ENDO/MYO) and myometrium (MYO) alone were collected on days 12-14 of the estrous cycle (control group; n = 5) or pregnancy (experimental group; n = 5). Two analogues of LPA at increasing doses were used: oleoyl-sn-glycero-3-phosphate (L-alpha-LPA, a selective agonist of LPA1 and LPA2 receptors; 10(-7) M; 10(-6) M and 10(-5) M) and 1-oleoyl-2-O-methyl-rac-glycerophosphothionate (OMPT, a selective agonist of LPA3 receptor; 68 nM; 136 nM and 680 nM). L-alpha-LPA caused an increase in the contraction tension, amplitude and frequency of ENDO/MYO from the uterine horn with the developing embryos. This effect was not observed in MYO in both groups examined. In the ENDO/MYO strips of the uterine horn with developing embryos, OMPT significantly increased the contraction tension at the highest dose (680 nM) and amplitude at all doses examined, while frequency of contractions was decreased at doses of 136 nM and 680 nM. In the MYO strips of the uterine horn with embryos a significant increase in the contraction tension and amplitude after the highest dose of OMPT was observed. The results obtained imply the important role of receptors LPA1, LPA2 and LPA3 in the contraction activity of the porcine uterus during early pregnancy.


Assuntos
Lisofosfolipídeos/farmacologia , Contração Muscular/fisiologia , Músculo Liso/fisiologia , Compostos Organotiofosforados/farmacologia , Ácidos Fosfatídicos/farmacologia , Suínos/fisiologia , Útero/fisiologia , Animais , Feminino , Lisofosfolipídeos/metabolismo , Compostos Organotiofosforados/metabolismo , Ácidos Fosfatídicos/metabolismo , Gravidez
9.
Pol J Vet Sci ; 15(1): 11-20, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22708352

RESUMO

WC1+ cells in cattle exhibit both regulatory and effector activities. However, it has not been elucidated whether they are so plastic that both activities co-exist in one cell or there are separate subpopulations of effector and regulatory cells. Since the production of IFN-gamma and IL-10 seems to be related to WC1+ cells' effector and regulatory function, respectively, the main aim of this study was to determine whether those cytokines are produced by separate subpopulations of WC1+, or are co-produced by the same cells. Due to increasingly frequent emphasised role of consumption of IL-2 in the mechanism of suppressor action of mouse CD25+CD4+ T regulatory cells, expression of the receptor's alpha chain for interleukin 2 (CD25) on WC1+ lymphocytes has been evaluated. An average of 5.21% of WC1+ cells obtained from PBMCs of 12-month-old heifers show constitutive expression of the CD25 molecule, with CD25(high)WC1+ and CD25(low)WC1+ cells accounting for 1.05% and 4.10% of WC1+ lymphocytes, respectively. For detection of intracellular cytokine production, PBMCs were stimulated with concanavalin A. Both IFN-gamma(-) and IL-10-producing cells within the CD25(-)WC1+ and CD25+WC1+ subpopulations were mainly separate subpopulations. The average percentage of IFN-gamma(+)IL-10(-), IFN-gamma(-)IL-10+ and IFN-gamma(+)IL-10+ cells among CD25(-)WC1+ lymphocytes was 4.03%, 2.67% and 0.51%, respectively. A positive correlation was observed between the presence of the CD25 molecule on WC1+ lymphocytes and production of IL-10 and TGF-beta, because the average percentage of IFN-gamma(-)IL-10+ and IFN-gamma(+)IL-10+ among CD25+WC1+ lymphocytes was 3 and 4.5 times higher as compared to the corresponding cells in the CD25(-)WC1+ subpopulation, whereas the percentage of IFN-gamma(+)IL-10(-) cells in both the subpopulations was not significantly different. The percentage of TGF-beta+ cells within the CD25+WC1+ subpopulation was 2.72 times as high as that of CD25(-)WC1+ lymphocytes. Therefore, with respect to the production of IFN-gamma, IL-10 and TGF-beta, CD25+WC1+ lymphocytes turn out to have a more suppressor profile than CD25(-)WC1+.


Assuntos
Bovinos , Interleucina-10/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Glicoproteínas de Membrana/metabolismo , Subpopulações de Linfócitos T/metabolismo , Animais , Células Cultivadas , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-10/genética , Subunidade alfa de Receptor de Interleucina-2/genética , Glicoproteínas de Membrana/genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo
10.
Pol J Vet Sci ; 13(1): 3-12, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21077425

RESUMO

The aim of the study was to determine whether treatment with recommended doses of meloxicam or flunixin had an effect on the apoptosis of peripheral blood T lymphocytes in calves. The study was carried out on 4-5 months old calves (n = 24, 8 per group). Experimental animals were injected subcutaneously with a single dose of 0.5 mg x kg(-1) of meloxicam or intravenously with 3 doses of 2.2 mg x kg(-1) day(-1) of flunixin. The non-treatment animals served as control. Blood samples were taken at day 0 and at days 1, 2, 3, 5, 7 and 14 after the first NSAIDs injection. Apoptosis was determined by flow cytometry using Annexin V-PE/7-AAD staining. The kinetic analysis of apoptosis in the total lymphocyte population, as well as in the CD4+ and CD8+ subsets did not reveal significant differences in the frequency of early apoptotic cells between control and experimental groups throughout the period studied. Although, 24 h after administration of the first dose of NSAIDs, late-stage apoptosis/necrosis was significantly increased in the total lymphocyte population (the meloxicam group), as well as in the CD4+ (the meloxicam group and the flunixin group) and CD8+ (the flunixin group) subsets of T cells. However, this disturbance was transient, relatively poorly expressed and, thus, unlikely to be of clinical significance. Our results indicate that the use of meloxicam or flunixin in accordance with the recommended dosage regimen in cattle do not have a clinically significant influence on apoptosis of peripheral blood T cells.


Assuntos
Apoptose/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Clonixina/análogos & derivados , Tiazinas/farmacologia , Tiazóis/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/fisiologia , Linfócitos T CD4-Positivos/fisiologia , Linfócitos T CD8-Positivos/fisiologia , Bovinos , Clonixina/farmacologia , Feminino , Masculino , Meloxicam
11.
Pol J Vet Sci ; 12(3): 305-10, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19886250

RESUMO

The objective of the present study was to determine the influence of nonsteroidal anti-inflammatory drugs (NSAIDs) representing different chemical groups on progesterone (P4) production by cultured bovine steroidogenic luteal cells. The cells were enzymatically isolated from corpora lutea collected on days 8-12 of the estrous cycle. After 24 h preincubation they were incubated for 24 h with medium only (control) or stimulated with bovine luteinizing hormone - LH (100 ng/ml; positive control) or increasing concentrations (10(-8) to 10(-4) M) of acetylsalicylic acid, indomethacin, ibuprofen, naproxen, piroxicam, phenylbutazone, dipyrone or nimesulide. Concentartions of P4 in the culture media were determined by enzyme immunoassay. LH significantly increased P4 secretion, while acetylsalicylic acid and indomethacin did not affect the production of this hormone. A significant increase in P4 secretion was observed after administration of dipyrone at all concentrations, piroxicam at concentrations of 10(-8), 10(-7) and 10(-5) M, phenylbutazone and naproxen at concentrations of 10(-7) and 10(-6) M and ibuprofen at concentrations of 10(-5) and 10(-4) M. Nimesulide did not affect P4 production at concentrations of 10(-8) - 10(-5) M, while at a concentration of 10(-4) M it inhibited P4 secretion. The results obtained indicate that NSAIDs may change the production of P4 in bovine luteal cells, however, these changes are dependent on the substance used.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Bovinos , Células Lúteas/efeitos dos fármacos , Células Lúteas/metabolismo , Progesterona/metabolismo , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Hormônio Luteinizante/farmacologia
12.
Pol J Vet Sci ; 11(3): 199-203, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18942540

RESUMO

The pharmacokinetics of flunixin meglumine was determined after its multiple (altogether 4 doses at 24-hours intervals) intravenous administration at a dose of 2.2 mg/kg body weight in six mature clinically healthy heifers. Plasma flunixin and its metabolite 5-hydroxyflunixin concentrations were analyzed with high-pressure liquid chromatography using an assay with a lower limit detection of 0.03 microg/ml for both substances. Plasma concentrations versus time curves were described by a two compartment open model. Mean plasma flunixin concentrations were similar on day 1 and 4, and than rapidly decreased (within 2 hours) from initial concentrations higher than 10 microg/ml to the concentrations lower than 1 microg/ml. The distribution phase of flunixin was short (t0.5 alpha = 0.29 +/- 0.16 and 0.18 +/- 0.04 on day 1 and 4, respectively) and the elimination phase was more prolonged (t0.5 beta = 3.30 +/- 0.60 and 3.26 +/- 0.22 on day 1 and 4, respectively). The mean residence time of flunixin was similar on day 1 (1.83 +/- 0.83) and 4 (1.88 +/- 0.46), and for 5-hydroxyflunixin this parameter was insignificantly (P > 0.05) higher on day 1 (5.49 +/- 2.22) as compared to that found on day 4 (3.99 +/- 2.17). The clearance of flunixin was similar on both examined days (0.23 +/- 0.12 on day 1 and 0.31 +/- 0.15 on day 4), and for 5-hydroxyflunixin was insignificantly (P > 0.05) lower on day 1 (2.37 +/- 1.21) as compared to that determined on day 4 (3.23 +/- 1.06). Our data indicate that multiple administration of flunixin did not alter significantly the parent drug and its metabolite concentrations in plasma, however may cause some small changes in pharmacokinetic parameters.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Bovinos/metabolismo , Clonixina/análogos & derivados , Animais , Área Sob a Curva , Bovinos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/veterinária , Clonixina/farmacocinética , Relação Dose-Resposta a Droga , Esquema de Medicação/veterinária , Feminino , Meia-Vida , Injeções Intravenosas/veterinária , Taxa de Depuração Metabólica , Fatores de Tempo
13.
Mol Biosyst ; 13(2): 277-313, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-27918060

RESUMO

The essential idea of regenerative medicine is to fix or replace tissues or organs with alive and patient-specific implants. Pluripotent stem cells are able to indefinitely self-renew and differentiate into all cell types of the body which makes them a potent substantial player in regenerative medicine. The easily accessible source of induced pluripotent stem cells may allow obtaining and cultivating tissues in vitro. Reprogramming refers to regression of mature cells to its initial pluripotent state. One of the approaches affecting pluripotency is the usage of low molecular mass compounds that can modulate enzymes and receptors leading to the formation of pluripotent stem cells (iPSCs). It would be great to assess the general character of such compounds and reveal their new derivatives or modifications to increase the cell reprogramming efficiency. Many improvements in the methods of pluripotency induction have been made by various groups in order to limit the immunogenicity and tumorigenesis, increase the efficiency and accelerate the kinetics. Understanding the epigenetic changes during the cellular reprogramming process will extend the comprehension of stem cell biology and lead to potential therapeutic approaches. There are compounds which have been already proven to be or for now only putative inducers of the pluripotent state that may substitute for the classic reprogramming factors (Oct3/4, Sox2, Klf4, c-Myc) in order to improve the time and efficiency of pluripotency induction. The effect of small molecules on gene expression is dosage-dependent and their application concentration needs to be strictly determined. In this review we analysed the role of small molecules in modulations leading to pluripotency induction, thereby contributing to our understanding of stem cell biology and uncovering the major mechanisms involved in that process.


Assuntos
Transdiferenciação Celular/efeitos dos fármacos , Reprogramação Celular/efeitos dos fármacos , Animais , Epigênese Genética/efeitos dos fármacos , Técnicas de Transferência de Genes , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator 4 Semelhante a Kruppel , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transgenes
14.
Supercond Sci Technol ; 30(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28360455

RESUMO

We performed a feasibility study on a high-strength Bi2-x Pb x Sr2Ca2Cu3O10-x (Bi-2223) tape conductor for high-field solenoid applications. The investigated conductor, DI-BSCCO Type HT-XX, is a pre-production version of Type HT-NX, which has recently become available from Sumitomo Electric Industries (SEI). It is based on their DI-BSCCO Type H tape, but laminated with a high-strength Ni-alloy. We used stress-strain characterizations, single- and double-bend tests, easy- and hard-way bent coil-turns at various radii, straight and helical samples in up to 31.2 T background field, and small 20-turn coils in up to 17 T background field to systematically determine the electro-mechanical limits in magnet-relevant conditions. In longitudinal tensile tests at 77 K, we found critical stress- and strain-levels of 516 MPa and 0.57%, respectively. In three decidedly different experiments we detected an amplification of the allowable strain with a combination of pure bending and Lorentz loading to ≥ 0.92% (calculated elastically at the outer tape edge). This significant strain level, and the fact that it is multi-filamentary conductor and available in the reacted and insulated state, makes DI-BSCCO HT-NX highly suitable for very high-field solenoids, for which high current densities and therefore high loads are required to retain manageable magnet dimensions.

15.
Clin Exp Med ; 6(2): 89-93, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16820997

RESUMO

Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) play a significant role in the metabolism of many biological substances. ADH participates in the metabolism of ethanol, retinoic acid, lipid peroxidation products, leukotriene and glutathione metabolism. ALDH is responsible for oxidation of acetaldehyde and other aldehydes and metabolism of histamine and retinoic acid. The aim of this study was to compare the metabolism in breast cancer cells and normal breast parenchyma by measuring ADH isoenzymes and ALDH activities in these tissues. Total ADH activity was measured by a photometric method with p-nitrosodimethylaniline (NDMA) as a substrate. For the measurement of the activity of ALDH and class I and II isoenzymes of ADH we employed the fluorometric methods, with class-specific fluorogenic substrates. The activity of class III alcohol dehydrogenase was detected by the photometric method with n-octanol and class IV with m-nitrobenzaldehyde as substrates. The samples were taken surgically during resection of breast carcinoma from 75 women. The activity of the class I ADH isoenzyme was significantly lower in breast cancer cells than in healthy tissues. The other tested classes of ADH had a tendency for higher levels of activity in cancer cells than in normal mammary tissue. The activity of total ADH and ALDH was also not significantly lower in the cancer cells. The decrease of activity of class I ADH isoenzyme in breast cancer tissues may be a factor of some disorders in metabolic pathways with participation of these isoenzymes that can lead to carcinogenesis.


Assuntos
Álcool Desidrogenase/metabolismo , Neoplasias da Mama/enzimologia , Isoenzimas/metabolismo , Feminino , Fluorometria , Humanos , Compostos Nitrosos/metabolismo , Especificidade por Substrato
16.
J Anim Sci ; 94(11): 4611-4618, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27898948

RESUMO

These studies were to demonstrate whether the ß-receptor is involved in regulating the contractility of the swine myometrium in the peri-implantation period and to compare a relaxing activity of selective ß- and ß-adrenergic agonists (salbutamol and BRL 37344, respectively). Myometrial strips were collected form the gilts ( = 8) on d 12 to 14 of pregnancy. Changes in the contractility of myometrial strips were assessed further to the administration of increasing concentrations of the agonists (10 to 10 ) with and without ß-adrenergic receptor antagonists: butoxamine, propranolol, and bupranolol at 10 . Moreover, the -log EC (pD) of the agonists were compared. Following the incubation of myometrial strips with salbutamol and BRL 37344, a significant ( < 0.05 to 0.001) reduction in the contractility, seen as decreased tension, amplitude, and frequency of contractions, as compared to the pretreatment period was noted, although salbutamol induced these changes at a concentration of 10 to 10 , whereas BRL 37344 induced them at 10 to 10 . Salbutamol exerted a significantly ( < 0.001) more potent reduction of the tension (pD = 6.98 ± 0.93 [SD]) than BRL 37344 (pD = 3.41 ± 0.1.61). The impact of salbutamol was neutralized by all administered antagonists, while a relaxing effect of BRL 37344 was completely inhibited by bupranolol and partially by propranolol. The data indicate that the ß-adenergic receptor is involved in the regulation of smooth muscle contractility in the swine uterus in the peri-implantation period and its activation triggers relaxation of the myometrium to a lesser degree than the activation of the ß-adrenergic receptor.


Assuntos
Albuterol/farmacologia , Implantação do Embrião/fisiologia , Etanolaminas/farmacologia , Miométrio/metabolismo , Suínos/fisiologia , Agonistas Adrenérgicos beta/farmacologia , Animais , Relação Dose-Resposta a Droga , Feminino , Gravidez , Receptores Adrenérgicos beta , Contração Uterina/efeitos dos fármacos
17.
J Physiol Pharmacol ; 67(4): 625-632, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27779483

RESUMO

Resiniferatoxin (RTX) is used as experimental drug therapy for a range of neurogenic urinary bladder disorders. The present study investigated the chemical coding of caudal mesenteric ganglion (CaMG) neurons supplying the porcine urinary bladder after intravesical RTX instillation. The CaMG neurons were visualized with retrograde tracer Fast Blue (FB) and their chemical profile was disclosed with double-labelling immunohistochemistry using antibodies against tyrosine hydroxylase (TH), neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), somatostatin (SOM), calbindin (CB), galanin (GAL) and neuronal nitric oxide synthase (nNOS). It was found that in both the control (n = 6) and RTX-treated pigs (n = 6), the vast majority (92.3 ± 2.7% and 93.1 ± 1.3%, respectively) of FB-positive (FB+) nerve cells were TH+. Intravesical instillation of RTX caused a decrease in the number of FB+ / TH + neurons immunopositive to NPY (91.0 ± 2.2% in control animals vs. 58.8 ± 5.0% in RTX-treated pigs) or VIP (1.7 ± 0.5% vs. 0%) and an increase in the number of FB+ / TH+ neurons immunoreactive to SOM (3.4 ± 1.5% vs. 20.6 ± 4.3%), CB (1.8 ±0.7% vs. 13.4 ± 2.3%), GAL (1.5 ± 0.6% vs. 7.5 ± 1.0%) or nNOS (0% vs. 10.9 ± 3.4%). The present results suggest that therapeutic effects of RTX on the mammalian urinary bladder can be partly mediated by CaMG neurons.


Assuntos
Diterpenos/farmacologia , Neurônios/efeitos dos fármacos , Bexiga Urinária/inervação , Animais , Feminino , Gânglios Simpáticos/citologia , Neurônios/metabolismo , Neurotoxinas/farmacologia , Suínos , Canais de Cátion TRPV/antagonistas & inibidores , Tirosina 3-Mono-Oxigenase/metabolismo
18.
J Am Coll Cardiol ; 18(4): 931-6, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1894866

RESUMO

To evaluate cardiac involvement in primary antiphospholipid syndrome, two-dimensional and Doppler echocardiographic studies were performed in 34 consecutive patients with this syndrome. All patients had an increased level of serum anticardiolipin antibodies with no evidence of malignancy or systemic lupus erythematosus. The clinical manifestations of primary antiphospholipid syndrome were arterial thrombosis in 14 patients, venous thrombosis in 6 and recurrent fetal loss in 14. Valvular lesions were observed on two-dimensional echocardiography in 11 patients (32%) (9 women and 2 men), aged 24 to 57 years (mean +/- 1 SD 36 +/- 10). Abnormal echocardiographic findings were observed in 9 (64%) of 14 patients with arterial thrombosis versus 1 (17%) of 6 patients with venous thrombosis and 1 (7%) of 14 patients with recurrent fetal loss. The most common echocardiographic abnormality was mitral leaflet thickening, found in five patients; this was associated with mitral regurgitation in three and with combined mild mitral stenosis and regurgitation in one patient. Localized subvalvular mitral thickening was observed in one patient and calcification of the anulus in another. Aortic valve thickening was observed in two patients, one of whom also had a moderate degree of aortic regurgitation. Vegetation-like lesions on the mitral or aortic valve were found in two patients. It is concluded that valvular lesions are commonly found in primary antiphospholipid syndrome, particularly when the syndrome is manifested by peripheral arterial thrombosis. The location and appearance of valvular lesions in this syndrome are heterogeneous. Most patients have no clinically significant valvular disease. Two-dimensional and Doppler echocardiographic studies are often informative in these patients.


Assuntos
Autoanticorpos/imunologia , Cardiolipinas/imunologia , Doenças das Valvas Cardíacas/imunologia , Fosfolipídeos/imunologia , Adulto , Ecocardiografia , Ecocardiografia Doppler , Feminino , Doenças das Valvas Cardíacas/diagnóstico por imagem , Humanos , Masculino , Tromboflebite/imunologia , Trombose/imunologia
19.
J Am Coll Cardiol ; 10(1): 170-7, 1987 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3597985

RESUMO

Nuclear magnetic resonance (NMR) imaging is a new, noninvasive approach for imaging the cardiovascular system. Being a three-dimensional technique, NMR imaging has the capability of measuring volumes without the need for assumptions regarding ventricular geometry. In this study, the technique was validated in 19 excised dog hearts, filled with silicone-rubber, imaged using a multislice spin-echo sequence. The volume of the cavity in each slice was calculated from the number of pixels outlined for each slice multiplied by the pixel volume. Ventricular volumes measured by NMR imaging were highly correlated with cast volumes measured by water displacement: right ventricle (RV):RVNMR = 1.05 RVcast - 1.62; r = 0.99, SEE = 0.96 ml; left ventricle (LV):LVNMR = 0.98 LVcast + 0.35, r = 0.98, SEE = 1.48 ml. After validation in casts, NMR imaging volumes were measured in eight living dogs using a multiphasic gated technique to obtain images at 5, 105, 205, 305 and 405 ms after the QRS complex. Cardiac output (CO) and stroke volume (SV) measured by NMR imaging were significantly correlated with thermodilution (TD) measurements (CONMR = 0.63 COTD + 0.51 liters/min; r = 0.78, SEE = 0.57 liters/min; SVNMR = 0.67 SVTD + 1.95 ml; SEE = 5.58 ml). Right and left stroke volumes were closely related (LVSVNMR = 0.9 RVSVNMR + 1.75; r = 0.94, SEE = 4.32 ml), with the slope and intercept of the regression line showing no difference from 1 and 0, respectively. However, volumes determined by NMR imaging underestimated the thermodilution measurements, presumably reflecting the inability to obtain a true systolic image with the present sampling rate.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Volume Sanguíneo , Circulação Coronária , Espectroscopia de Ressonância Magnética , Animais , Cães , Ventrículos do Coração , Modelos Anatômicos , Termodiluição/métodos
20.
J Magn Reson ; 177(1): 1-8, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16125429

RESUMO

Access to an ultra-wide bore (105 mm) 21.1 T magnet makes possible numerous advances in NMR spectroscopy and MR imaging, as well as novel applications. This magnet was developed, designed, manufactured and tested at the National High Magnetic Field Laboratory and on July 21, 2004 it was energized to 21.1 T. Commercial and unique homebuilt probes, along with a standard commercial NMR console have been installed and tested with many science applications to develop this spectrometer as a user facility. Solution NMR of membrane proteins with enhanced resolution, new pulse sequences for solid state NMR taking advantage of narrowed proton linewidths, and enhanced spatial resolution and contrast leading to improved animal imaging have been documented. In addition, it is demonstrated that spectroscopy of single site (17)O labeled macromolecules in a hydrated lipid bilayer environment can be recorded in a remarkably short period of time. (17)O spectra of aligned samples show the potential for using this data for orientational restraints and for characterizing unique details of cation binding properties to ion channels. The success of this NHMFL magnet illustrates the potential for using a similar magnet design as an outsert for high temperature superconducting insert coils to achieve an NMR magnet with a field >25 T.


Assuntos
Espectroscopia de Ressonância Magnética/instrumentação , Proteínas de Membrana/química , Aumento da Imagem/instrumentação , Ressonância Magnética Nuclear Biomolecular/instrumentação , Sensibilidade e Especificidade
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