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1.
Toxicol Appl Pharmacol ; 427: 115667, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34343560

RESUMO

Dichlorodiphenyltrichloroethane (DDT) is a representative organochlorine insecticide and a known endocrine disruptor. Malathion is an organophosphate insecticide and a next-generation pesticide. Previously, it was shown that oxytocin (OT) and prostaglandins (PGs) are involved in the mechanism of the adverse effect of DDT on bovine myometrial contractions. However, disruption of myometrial contractions without disruption of cervical activity may not be sufficient to cause preterm delivery. Hence, the aim of this study was to determine the effects of insecticides on the function of the bovine cervix at preovulation period. Bovine cervical cells or strips were treated with DDT or malathion (0.1-100 ng/ml), and neither DDT nor malathion (each at a dose of 100 ng/ml) affected the viability of cervical cells. Malathion (0.1-10 ng/ml) and the high doses of DDT (10 ng/ml) decreased the force of cervical contractions, in contrast to a low dose of DDT (0.1 ng/ml). Both insecticides also decreased the mRNA expression of the OT receptor and the level of the second messenger (inositol triphosphate, IP3). Moreover, DDT decreased the amount of other second messengers (diacylglycerol, DAG), while malathion decreased the amount of gap junction protein (GAP). Only malathion increased PGE2 and decreased PGF2α secretion, while neither insecticide had an effect on both prostaglandins synthesis. Both DDT and malathion impaired cervical contractions, secretory function and cellular signalling. It is also possible that malathion-mediated induction of locally produced PGE2 can be followed by cervical softening. Admittedly it was shown that DDT and malathion can evoke failures in the regulation of motor function of cervix during oestrus cycle, while their harmful effect on gestation can be also not excluded.


Assuntos
Colo do Útero/efeitos dos fármacos , DDT/toxicidade , Inseticidas/toxicidade , Malation/toxicidade , Músculo Liso/efeitos dos fármacos , Contração Uterina/efeitos dos fármacos , Animais , Bovinos , Colo do Útero/fisiologia , Relação Dose-Resposta a Droga , Feminino , Músculo Liso/fisiologia , Técnicas de Cultura de Órgãos , Contração Uterina/fisiologia
2.
Pol J Vet Sci ; 24(1): 5-12, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33847092

RESUMO

Dieldrin and DDE are environmental metabolites of the organochlorine pesticides aldrin and DDT, respectively. During pregnancy, these chemicals can quickly infiltrate through the placental barrier, accumulate in amniotic fluid and fetus, and act as endocrine disruptors (EDs). The aim of this study was to investigate the effect of DDE and dieldrin and their parental substances at concentrations of 1 and 10 ng/ml on secretion of PGE2 and PGF2α from bovine endometrial explants (120-150 and 151-180 days of pregnancy) after 24 hr of incubation with EDs. The mRNA expression of COX2, PGES and PGFS and the concentrations of PGE2 and PGF2α were measured. EDs did not affect (p>0.05) COX2 gene expression, but DDT and DDE decreased (p⟨0.05) PGES expression and PGE2 secretion in the explants from 120-150 days of pregnancy. Depending on the dose, DDT and DDE increased (p⟨0.05) PGFS expression and PGF2α secretion from the explants from 120-150 days and decreased PGF2α secretion (p⟨0.05) from the explants from 151-180 days of pregnancy. Aldrin and dieldrin decreased (p⟨0.05) PGFS expression and PGF2α secretion from all explants. In summary, EDs disrupt the secretion of PGE2 and PGF2α by influencing the gene expression of PGES and PGFS.


Assuntos
Bovinos/fisiologia , Dinoprosta/metabolismo , Dinoprostona/metabolismo , Endométrio/efeitos dos fármacos , Inseticidas/farmacologia , Aldrina/farmacologia , Aldrina/toxicidade , Animais , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , DDT/farmacologia , DDT/toxicidade , Diclorodifenil Dicloroetileno/farmacologia , Diclorodifenil Dicloroetileno/toxicidade , Dieldrin/farmacologia , Dieldrin/toxicidade , Dinoprosta/genética , Dinoprostona/genética , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Inseticidas/metabolismo , Inseticidas/toxicidade , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Técnicas de Cultura de Tecidos/veterinária
3.
Anim Reprod Sci ; 223: 106623, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33132122

RESUMO

Chlorooganic xenobiotics (XBs) such as DDT, DDE, aldrin and dieldrin interfere with release of hormones from chorionic villi that are necessary for sustaining the normal course pregnancy: prostaglandins (PGs), oxytocin (OT), progesterone (P4) and estradiol (E2). Approximately 20 %-40 % of these hormones originate from the smooth chorion. The aim of current studies was to investigate effects of these XBs on synthesis and release of PGE2, PGF2α, OT, P4 and E2 from explants of smooth chorion of cattle, obtained during the120-150 and 151-180 day gestational period. Explants were incubated with DDT, DDE, aldrin or dieldrin at concentrations of 1 and 10 ng/mL for 24 h, and concentrations of PGE2, PGF2α, OT, P4 and E2 in post incubation medium and the relative abundances of COX-2, PTGES, AKR1B1, NP-I/OT, PAM, HSD3B, and CYP19A1 mRNA transcripts in tissue explants were determined. The XBs did not have effects on cell viability in explants (P > 0.05), however, there were effects on prostaglandins, OT and P4 secretion and relative abundance of mRNA transcript for genes encoding the main enzymes involved in synthesis of these hormones (P < 0.05). The XBs that were evaluated did not have effects on E2 synthesis and secretion (P > 0.05). In summary, XBs evaluated in the present study had effects on the pattern of prostaglandin secretion, and can increase OT and P4 release from smooth chorion explants. Because XBs inhibit hormonal action throughout the chorion, there is an increase in risk of abortions or premature births in animals.


Assuntos
Córion/efeitos dos fármacos , Hormônios Esteroides Gonadais/metabolismo , Inseticidas/toxicidade , Ocitocina/metabolismo , Prostaglandinas/metabolismo , Aldrina/toxicidade , Animais , Bovinos , Córion/citologia , DDT/toxicidade , Diclorodifenil Dicloroetileno/toxicidade , Dieldrin/toxicidade , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônios Esteroides Gonadais/genética , Ocitocina/genética , Gravidez , Prostaglandinas/genética , Técnicas de Cultura de Tecidos
5.
J Laryngol Otol ; 132(9): 802-806, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30180914

RESUMO

BACKGROUND: A subset of patients with bone-anchored hearing aids develop skin reactions that may be related to excess skin mobility around the skin-penetrating abutments. However, there is a lack of reports on the extent of skin mobility within the retroauricular space, typical for the implant location. METHODS: This study was based on photographic analysis of the relative shifts between the skull and soft tissue of the head in the retroauricular region, detected under the physiological conditions of head support and facial muscle contraction. RESULTS: The mean calculated value for skin shifts at the implant site was 5.1 mm. In 84 per cent of cases, the extent of skin shift was greater with the head at rest, by an average of 3.1 mm. The extent of skin movement during facial muscle contraction ranged between 0 mm and 8.9 mm. No direct correlations were detected between the extent and direction of skin shifts and patients' age, gender or body mass index. CONCLUSION: There are no objective data that can predict individual skin movement at the osseointegrated implant site. The study confirmed high variability in terms of the direction and extent of skin shift, which should be discussed when managing related skin problems.


Assuntos
Auxiliares de Audição/efeitos adversos , Pele/fisiopatologia , Crânio/patologia , Âncoras de Sutura/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Condução Óssea/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento/fisiologia , Contração Muscular/fisiologia , Osseointegração/fisiologia , Fotografação/métodos , Fenômenos Fisiológicos da Pele , Crânio/cirurgia , Âncoras de Sutura/normas
6.
Anaesthesist ; 63(8-9): 691-6, 2014 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-25056410

RESUMO

BACKGROUND: Prehospital emergency medicine is a challenge for trainee emergency physicians. Rare injuries and diseases as well as patients in extreme age groups can unexpectedly face emergency physicians. In the regulations on medical education the German Medical Association requires participation in 50 emergency missions under the supervision of an experienced emergency physician. This needs to be improved because on-the-job training does not generally represent the whole spectrum of emergency medicine and a good and structured training under on call conditions is nearly impossible. AIM: The subject of the model project described was whether practical training for emergency physicians can be achieved by participation in simulation training instead of real emergency situations. MATERIAL AND METHODS: After modification of the Saarland regulations on medical education it was possible to replace up to 25 participations in emergency missions by simulation training. The concept of the course NASimSaar25 requires participants to complete 25 simulator cases in 3 days in small training groups. Emergency situations from all medical disciplines need to be treated. A special focus is on the treatment of life-threatening and rare diseases and injuries. Modern simulators and actors are used. The debriefings are conducted by experienced tutors based on approved principles. Medical contents, learning targets from the field of crew resource management (CRM) and soft skills are discussed in these debriefings. RESULTS: Education in the field of emergency medicine can be improved by simulator-based learning and training. However, practical work under a tutor in real and clinical experience cannot be completely replaced by simulation. Simulator training can only be successful if theoretical knowledge has already been acquired. CONCLUSION: A simulator-based course concept can result in an improvement of emergency medical education. The model project NASimSaar25 was well received by the target audience and mostly very well evaluated in terms of learning and reality. If this project becomes established the demand on simulation-based training will increase. The training should achieve a consistent standard of quality.


Assuntos
Medicina de Emergência/educação , Simulação de Paciente , Médicos , Competência Clínica , Simulação por Computador , Currículo , Medicina de Emergência/legislação & jurisprudência , Alemanha , Humanos , Capacitação em Serviço
7.
Theriogenology ; 81(7): 877-86, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24576709

RESUMO

The orphan receptor steroidogenic factor-1 (SF-1) is involved in the regulation of ovarian steroidogenesis in cows. It is hypothesized that estrogen-like chlorinated compounds might affect SF-1, and thus impair the function of the ovary. Bovine luteal cells from the estrous cycle (Days: 1-5, 6-10, 11-15, and 16-19) were treated for 50 hours with DDT, 1,1-dichloro-2,2-bis(4-chlorophenyl)ethene, 3,3'4,4'-tetrachlorobiphenyl or 2'2'4,4',5,5'-hexachlorobiphenyl (each at a dose of 10 ng/mL). Luteal cells were also treated with 4-(heptyloxy)phenol (1 × 10(-7) M), an SF-1 agonist, and F0160 (1 × 10(-6) M), an SF-1 blocker, jointly or separately. The secretion of progesterone and oxytocin and the expression of oxytocin precursor (NP-I/OT) messenger RNA were increased (P < 0.05) by all studied xenobiotics and 4-(heptyloxy)phenol, although they were inhibited (P < 0.05) by F0160. However, the xenobiotics did not affect (P > 0.05) SF-1 messenger RNA expression. In summary, SF-1 is involved in the adverse effect of chlorinated xenobiotics on the regulation of the bovine CL.


Assuntos
Bovinos , Poluentes Ambientais/toxicidade , Ciclo Estral/fisiologia , Células Lúteas/metabolismo , Fator Esteroidogênico 1/metabolismo , Animais , Células Cultivadas , DDT/toxicidade , Diclorodifenil Dicloroetileno/toxicidade , Feminino , Regulação da Expressão Gênica/fisiologia , Ocitocina/metabolismo , Bifenilos Policlorados/toxicidade , Esteroides/metabolismo
8.
Anim Reprod Sci ; 143(1-4): 30-7, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24215672

RESUMO

Polychlorinated biphenyls (PCBs), DDT and its metabolite (DDE) belong to estrogen-like endocrine disruptors. However, though their activity is approximately 1000-fold lower than the activity of estradiol (E2), this steroid's high concentration in follicular fluid and incubation media does not inhibit the influence of these xenobiotics. It was hypothesized that these xenobiotics might affect Steroidogenic Factor-1 (SF-1) and impair ovary function. To test this hypothesis, granulosa cells were obtained from ovarian follicles >1 or <1cm in diameter, which were treated with PCB-77, PCB-153, DDT or DDE (each at 10ng/ml), alone or jointly with an SF-1 antagonist (F0160). Treatment with the SF-1 antagonist inhibited (P<0.05) the secretion of P4 from cells of both sizes of follicles, as induced (P<0.05) by an SF-1 activator (HxP), DDE or PCB-153. All xenobiotics and HxP stimulated (P<0.05) the synthesis and secretion of oxytocin (OT). However, the effect on mRNA expression for NP-I/OT, which is OT precursor, was inhibited (P<0.05) by F0160 in all cultures treated with PCB-77, except for granulosa cells derived from follicles <1cm. Moreover, F0160 inhibited the effect on OT secretion of HxP, as well as all xenobiotics except for PCB-77 and DDE, in granulosa cells derived from follicles <1cm. Xenobiotic treatment did not affect (P>0.05) the expression for SF-1 mRNA. It is suggested that the SF-1 receptor may be involved in the adverse effects of xenobiotics on P4 secretion as well as the synthesis and secretion of OT.


Assuntos
DDT/farmacologia , Diclorodifenil Dicloroetileno/farmacologia , Hormônios Esteroides Gonadais/metabolismo , Células da Granulosa/efeitos dos fármacos , Ocitocina/metabolismo , Bifenilos Policlorados/farmacologia , Fator Esteroidogênico 1/fisiologia , Animais , Bovinos , Células Cultivadas , Dioxanos/farmacologia , Relação Dose-Resposta a Droga , Feminino , Células da Granulosa/metabolismo , Isoquinolinas/farmacologia , Receptores Nucleares Órfãos/fisiologia , Fator Esteroidogênico 1/antagonistas & inibidores
9.
Anim Reprod Sci ; 138(1-2): 74-81, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23481593

RESUMO

The orphan receptor Steroidogenic Factor-1 (SF-1, NR5A1), a member of the nuclear receptor superfamily, is present in fetal and adult steroidogenic tissues and also participates in the regulation of ovarian function. In this study, the expression levels of SF-1 mRNA and protein were determined in granulosa cells (from follicles >1cm and <1cm in diameter) and luteal tissue (from days 1-5, 6-10, 11-15, and 16-19 of the estrous cycle and weeks 3-5, 6-8, and 9-12 of pregnancy). Additionally, the effects of a synthetic SF-1 stimulator (4-(heptyloxy)phenol - HxP; 1×10(-7)M) and a synthetic SF-1 inhibitor (F0160; 1×10(-5)M) on the secretion of estradiol and oxytocin (OT) from granulosa cells (from follicles>1cm) and the secretion of progesterone (P4) and OT from luteal cells (days 11-16 of the estrous cycle) were investigated. The levels of SF-1 mRNA and protein were higher in granulosa cells (P<0.05) from follicles>1cm than in cells from follicles<1cm. In luteal tissue, the mRNA abundance was the highest (P<0.05) on days 6-10 of the estrous cycle, and the amount of protein was the highest on days 6-15 (P<0.05). The lowest levels of mRNA and protein for SF-1 were observed on days 16-19 of the estrous cycle (P<0.05). The abundance of SF-1 mRNA decreased at 9-12 weeks of pregnancy (P<0.05). The stimulation of the studied cells with HxP increased P4 and estradiol secretion from luteal and granulosa cells, respectively, and OT secretion from both types of cells. The SF-1 inhibitor did not affect hormone secretion by either type of cell, but it did diminish the effect induced by the SF-1 stimulator. The obtained data revealed estrous cycle-dependent levels of mRNA and protein for SF-1 in luteal tissue, and the use of a specific SF-1 stimulator and a specific SF-1 inhibitor confirmed the involvement of this receptor in steroidogenesis and OT secretion from cultured granulosa and luteal cells. These findings suggest that the SF-1 receptor participates in the local regulation of ovarian function during both the estrous cycle and the first trimester of pregnancy in cows. Furthermore, the concentrations of the SF-1 inhibitor and stimulator that we used in the primary cell culture could effectively modify the activity of this receptor.


Assuntos
Estradiol/metabolismo , Ciclo Estral/metabolismo , Ovário/metabolismo , Ocitocina/metabolismo , Primeiro Trimestre da Gravidez/metabolismo , Fator Esteroidogênico 1/metabolismo , Animais , Western Blotting , Bovinos , Dioxanos/farmacologia , Feminino , Células da Granulosa/metabolismo , Isoquinolinas/farmacologia , Células Lúteas/metabolismo , Ovário/citologia , Fenóis/farmacologia , Gravidez , RNA Mensageiro/química , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Estatísticas não Paramétricas , Fator Esteroidogênico 1/genética
10.
Environ Toxicol ; 28(7): 411-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21656645

RESUMO

Coumestrol is one of a few biologically active substances present in leguminous plants, which are widely used as fodder for ruminants. Depending on the doses, coumestrol acts on the reproductive processes as an estrogen-like factor or antiestrogen to evoke a decrease in ovulation frequency, elongation of estrous cycle duration. The aim of the current investigations was to study the influence of coumestrol on secretory function of luteal cells obtained from first trimester of pregnant cows. Luteal cells (2.5 × 10(5) /mL) from 3rd to 5th, 6th to 8th, and 9th to 12th week of pregnancy were preincubated for 24 h and incubated with coumestrol (1 × 10(-6) M) for successive 48 h and the medium concentrations of progesterone (P4), oxytocin (OT), prostaglandin (PG) E2 and F2α were determined. Moreover, the expression of mRNA for neurophysin-I/oxytocin (NP-I/OT; precursor of OT) and peptidyl-glycine-α-amidating mono-oxygenase (PGA, an enzyme responsible for post-translational OT synthesis) was determined after 8 h of treatment. Coumestrol did not affect P4 secretion but increased the secretion of OT from the cells collected at all stages of gestation studied. Hence, the ratio of P4 to OT was markedly decreased. Simultaneously, coumestrol increased the expression of NP-I/OT mRNA during 9th to 12th weeks of pregnancy, and mRNA for PGA during 3rd to 5th and 9th to 12th weeks of gestation. Furthermore, coumestrol decreased PGE2 secretion from luteal cells in all studied stages of pregnancy, while it affected PGF2α metabolite (PGFM) concentration only from week 3 to 5 of pregnancy. Obtained results suggest that coumestrol impairs secretory function of the corpus luteum (CL) and this way it can affect the maintenance of pregnancy in the cow.


Assuntos
Cumestrol/farmacologia , Células Lúteas/efeitos dos fármacos , Fitoestrógenos/farmacologia , Prenhez/efeitos dos fármacos , Animais , Bovinos , Dinoprosta/metabolismo , Dinoprostona/metabolismo , Feminino , Humanos , Células Lúteas/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/metabolismo , Neurofisinas/genética , Neurofisinas/metabolismo , Ocitocina/metabolismo , Gravidez , Prenhez/fisiologia , Progesterona/metabolismo , RNA Mensageiro/metabolismo
11.
Reprod Domest Anim ; 46(1): 21-8, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19799752

RESUMO

The current investigations were undertaken to study the mechanism of the adverse effect of phytoestrogens on the function of bovine granulosa (follicles >1< cm in diameter) and luteal cells from day 1-5, 6-10, 11-15, 16-19 of the oestrous cycle. The cells were incubated with genistein, daidzein or coumestrol (each at the dose of 1 × 10(-6) m). The viability and secretion of estradiol (E2), progesterone (P4) and oxytocin (OT) were measured after 72 h of incubation. Moreover, the expression of mRNA for neurophysin-I/OT (NP-I/OT; precursor of OT) and peptidyl-glycine-α-amidating monooxygenase (PGA, an enzyme responsible for post-translational OT synthesis) was determined after 8 h of treatment. None of the phytoestrogens used affected the viability of cells except for coumestrol. The increased secretion of E2 and P4 was only obtained by coumestrol (p<0.05) from granulosa cells from follicles <1cm in diameter and decreased from luteal cells on days 11-15 of the oestrous cycle, respectively. All three phytoestrogens stimulated (p<0.05) OT secretion from granulosa and luteal cells in all stages of the oestrous cycle and the expression of NP-I/OT mRNA in the both types of cells. The expression of mRNA for PGA was stimulated (p<0.05) by daidzein and coumestrol in granulosa cells, and by genistein and coumestrol in luteal cells. In conclusion, our results demonstrate that these phytoestrogens can impair the ovary function in cattle by adversely affecting the synthesis of OT in follicles and in corpus luteum. However, their influence on the ovarian steroids secretion was less evident.


Assuntos
Bovinos/metabolismo , Ovário/efeitos dos fármacos , Ocitocina/biossíntese , Ocitocina/metabolismo , Fitoestrógenos/efeitos adversos , Animais , Células Cultivadas , Cumestrol/farmacologia , Feminino , Genisteína/farmacologia , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Isoflavonas/farmacologia , Células Lúteas/efeitos dos fármacos , Células Lúteas/metabolismo , Oxigenases de Função Mista/genética , Complexos Multienzimáticos/genética , Neurofisinas/genética , Ovário/metabolismo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
12.
Amino Acids ; 41(1): 131-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20414692

RESUMO

It has been observed that astrocyte and astrocytoma cells differ in their response to D-ribose-L-cysteine (RibCys) in the culture medium. RibCys, a prodrug of L-cysteine, elevates the level of cysteine and glutathione in both astrocytoma and astrocyte cultures. It also affects the activity of two sulfurtransferases, 3-mercaptopyruvate sulfurtransferase and rhodanese, involved in the metabolism of sulfane sulfur-containing compounds and in consequence exerts an effect on the level of sulfane sulfur. Under conditions, in which the raised level of sulfane sulfur was accompanied by an elevated activity of 3-mercaptopyruvate sulfurtransferase, the proliferation of the human astrocytome U373 line was decreased. The experiments were simultaneously performed with murine astrocytes to compare the behavior of normal cells under similar conditions. In murine astrocytes, RibCys was capable of increasing cellular proliferation, and was accompanied by a diminished level of sulfane sulfur and unchanged activity of the two sulfurtransferases. Thus, RibCys might offer a therapeutic advantage in the inhibition of astrocytoma cell proliferation. Besides, in the absence of oxidative stress, measured as the ratio of GSH/GSSG, the obtained results confirm that the fall in the level of sulfane sulfur is associated with increasing proliferation of cells, whereas a rise in the level causes a decrease in the proliferation of U373 cells.


Assuntos
Antineoplásicos/farmacologia , Astrócitos/efeitos dos fármacos , Astrocitoma/tratamento farmacológico , Pró-Fármacos/farmacologia , Tiazolidinas/farmacologia , Animais , Antineoplásicos/química , Astrocitoma/patologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cisteína/análise , Avaliação Pré-Clínica de Medicamentos , Glutationa/análise , Humanos , Camundongos , Pró-Fármacos/química , Relação Estrutura-Atividade , Tiazolidinas/química
13.
J Microsc ; 237(3): 481-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20500422

RESUMO

An alloy with a chemical composition of Ti-45Al-5V (at.%) was synthesized by mechanical alloying in a Szegvari-type attritor from elemental powders of high purity. Before compaction, the powders were characterized by X-ray diffraction and scanning as well as transmission electron microscopy. The compaction of powders was carried out by hot isostatic pressing and hot isostatic extrusion. The resulting material was subjected to microstructural and mechanical characterization. The microstructure investigated by transmission and scanning electron microscopy supplemented by X-ray diffraction revealed that the bulk material was composed of a mixture of TiAl- and Ti(3)Al-based phases, however, the typical lamellar microstructure for such alloys was not observed. The materials exhibited exceptionally high yield strength together with satisfactory ductility and fracture toughness. The high strength was unequivocally due to grain refinement and the presence of oxide dispersoid.

14.
J Plast Reconstr Aesthet Surg ; 63(8): 1305-11, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19631596

RESUMO

Surgical treatment of hand contractures and pseudosyndactyly in Epidermolysis bullosa poses numerous medical and hospital management problems. For instance, the exceptional fragility of genetically defective epidermis may contribute to iatrogenic trauma or hamper and prolong healing. The interval between unavoidable contracture recurrences rarely exceeds 2 years; therefore, a search for quick treatment completion should be considered by the surgical teams. Because this goal is rarely achieved, even efforts aimed at facilitating operative procedures and improving patient comfort are often quite valuable. This study presents the initial results on the use of the Biobrane dressing in six cases with various degrees of hand contracture. Application of the product in the form of gloves was fast and easy, promoted epithelialisation and substantially reduced the risk of iatrogenic trauma during replacement of the dressings. The use of Biobrane also enabled rapid elimination of additional protective dressing layers, exposure of the healing skin and prevention of further epidermal maceration. However, the time and number of necessary procedures under anaesthesia was dependent upon the degree of hand deformity rather than on Biobrane use, so this treatment did not shorten the healing time to less than 4 weeks.


Assuntos
Materiais Revestidos Biocompatíveis/uso terapêutico , Contratura/cirurgia , Epidermólise Bolhosa Distrófica/cirurgia , Deformidades Adquiridas da Mão/cirurgia , Mãos , Procedimentos de Cirurgia Plástica/instrumentação , Cuidados Pós-Operatórios/métodos , Criança , Pré-Escolar , Contratura/complicações , Epidermólise Bolhosa Distrófica/complicações , Feminino , Deformidades Adquiridas da Mão/etiologia , Humanos , Masculino , Curativos Oclusivos , Transplante de Pele , Resultado do Tratamento , Cicatrização
15.
Vnitr Lek ; 55(3): 272-5, 2009 Mar.
Artigo em Tcheco | MEDLINE | ID: mdl-19378859

RESUMO

The management of warfarin therapy in patients undergoing surgery or other invasive procedures involves a balance between the risk of hemorrhage, and the risk of thrombosis. Risk of hemorrhage and the trombosis depends on the type of procedure and on pre-existing conditions. Procedures with low risk of hemorrhage (dental, dermatologic or ophtalmologic procedures, endoscopy) can be provided with continuing anticoagulant therapy. Surgery with high hemorrhagic risk need stop warfarin and start bridging anticoagulant therapy, such as unfractionated heparin or low molecular weight heparin, prior and after surgery. In patients requiring emergency surgery, vitamin K, prothrombin complex concentrate or fresh frozen plasma can be used to improve coagulation.


Assuntos
Anticoagulantes/uso terapêutico , Cuidados Pré-Operatórios , Anticoagulantes/administração & dosagem , Emergências , Hemorragia/induzido quimicamente , Hemorragia/prevenção & controle , Heparina de Baixo Peso Molecular/administração & dosagem , Humanos , Assistência Perioperatória , Fatores de Risco , Varfarina/uso terapêutico
16.
Analyst ; 133(11): 1523-31, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18936829

RESUMO

Near-infrared reflectance spectroscopy (NIRS) is often applied when a rapid quantification of major components in feed is required. This technique is preferred over the other analytical techniques due to the relatively few requirements concerning sample preparations, high efficiency and low costs of the analysis. In this study, NIRS was used to control the content of crude protein, fat and fibre in extracted rapeseed meal which was produced in the local industrial crushing plant. For modelling the NIR data, the partial least squares approach (PLS) was used. The satisfactory prediction errors were equal to 1.12, 0.13 and 0.45 (expressed in percentages referring to dry mass) for crude protein, fat and fibre content, respectively. To point out the key spectral regions which are important for modelling, uninformative variable elimination PLS, PLS with jackknife-based variable elimination, PLS with bootstrap-based variable elimination and the orthogonal partial least squares approach were compared for the data studied. They enabled an easier interpretation of the calibration models in terms of absorption bands and led to similar predictions for test samples compared to the initial models.


Assuntos
Ração Animal/análise , Brassica rapa , Modelos Estatísticos , Animais , Calibragem , Gorduras na Dieta/análise , Fibras na Dieta/análise , Proteínas Alimentares/análise , Espectroscopia de Luz Próxima ao Infravermelho/métodos
17.
Diabetes Metab ; 34(4 Pt 1): 349-54, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18585071

RESUMO

AIM: The aim of this randomized, placebo-controlled, double-blind study was to assess whether a low frequency magnetic field can influence pain intensity, quality of life and sleep, and glycaemic control in patients with painful diabetic polyneuropathy. METHODS: Sixty-one patients were randomized into two groups: the study group comprised 32 patients exposed to a low frequency magnetic field, average pain duration 23 months; the control group included 29 patients who received sham exposure, average pain duration 28 months. Patients were exposed for three weeks, 20 min a day, five days a week. The magnetic field generator was a Viofor JPS device (Med & Life, Komorow, Poland). All subjects filled out the following questionnaires five times (at the beginning and after one, two, three and five weeks): SFMPQ-VAS (pain evaluation), EuroQol EQ-5D and MOS Sleep Scale. HbA(1c) was evaluated at baseline and after five weeks. RESULTS: Significant reductions in pain intensity were seen in both the study group (visual analogue scale [VAS] value of 73 mm at baseline versus 33 mm after three weeks) and controls (VAS 69 mm at baseline versus 41 mm after three weeks). The extent of pain reduction did not differ significantly between the groups at any time. Also, both groups had similar improvements in EuroQol, MOS and HbA(1c) values. CONCLUSION: Genuine magnetic field exposure has no advantage over sham exposure in reducing pain intensity, improving quality of life, and decreasing sleep disturbances and HbA(1c).


Assuntos
Neuropatias Diabéticas/terapia , Campos Eletromagnéticos , Manejo da Dor , Qualidade de Vida , Transtornos do Sono-Vigília/terapia , Adulto , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Inquéritos e Questionários
18.
Amino Acids ; 34(2): 231-7, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17450321

RESUMO

N-acetyl-L-cysteine (NAC), a precursor of L-cysteine, not only elevates the level of glutathione in both astrocytoma and astrocyte cultures, but also affects the cellular level of sulfane sulfur. Astrocytoma cells were investigated using the stable U373 human cell line. In the U373 cells, N-acetyl-L-cysteine, depending on the concentration in the culture medium and culture duration, either elevated or diminished the level of sulfane sulfur, and this was respectively accompanied by decreased or increased cellular proliferation. In murine astrocytes, in turn, NAC was capable of lowering the level of sulfane sulfur and in this way decreased cellular proliferation. It seems that normal (astrocyte) and transformed (astrocytoma) cells differed in their reaction to NAC in the culture medium. The effect of N-acetyl-L-cysteine on astrocytoma cells was advantageous in that it inhibited their proliferation through the elevation of the level of sulfane sulfur.


Assuntos
Acetilcisteína/metabolismo , Astrócitos/metabolismo , Astrocitoma/metabolismo , Proliferação de Células/efeitos dos fármacos , Dissulfetos/metabolismo , Compostos de Sulfidrila/metabolismo , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Células Cultivadas , Glutationa/metabolismo , Humanos , Camundongos , Sulfurtransferases/antagonistas & inibidores , Sulfurtransferases/metabolismo , Tiossulfato Sulfurtransferase/antagonistas & inibidores , Tiossulfato Sulfurtransferase/metabolismo
19.
Exp Clin Endocrinol Diabetes ; 115(1): 55-7, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17286237

RESUMO

In patients with diabetes mellitus, Charcot's neuroarthropathy mainly affects major weight-bearing joints, especially the foot and ankle. Remarkably, we report a case of Charcot's joint of the wrist - an unusually rare localization in type 2 diabetic patient. A review of medical literature identified only three such cases so far.


Assuntos
Artropatia Neurogênica/complicações , Diabetes Mellitus Tipo 2/complicações , Articulação do Punho , Artropatia Neurogênica/patologia , Diabetes Mellitus Tipo 2/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Articulação do Punho/patologia
20.
J Microsc ; 224(Pt 1): 24-6, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17100898

RESUMO

The material used in this study was a commercial HAYNES alloy 242 with a nominal composition of Ni-25% Mo-8% Cr (in wt.%). In the standard heat treatment, the 242 alloy is annealed at a temperature between 1065 and 1095 degrees C and then water quenched. The ageing treatment is carried out at 650 degrees C for 24 h in order to develop the long-range-order strengthening. The alloy in the conventionally aged condition was additionally cold rolled to 50% reduction in thickness and subsequently subjected to prolonged ageing at 650 degrees C for 4000 h. The enhanced diffusion resulted in the decomposition of the Ni(2)(Mo,Cr) metastable phase into the stable Ni(3)Mo-based phase. The presence of the new stable phase increased the yield and tensile strengths but deteriorated the ductility of the alloy at both room and 650 degrees C temperatures.

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