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1.
Physiol Res ; 70(5): 755-764, 2021 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-34505534

RESUMO

Beneficial effects of Sambucus nigra L. (black elder) as a traditional medicine have been associated with the phytoconstituents including polyphenols, terpenes and lectins. Various antioxidant rich natural products have also been implicated with improvement of reproductive health and fertility, however, the effect of Sambucus nigra on the ovarian cell functions has not been investigated yet. The objectives of the present study were to screen the polyphenols in the elderflower and elderberry extracts, and to examine the secretion activity of steroid hormones 17beta-estradiol and progesterone by human ovarian granulosa cells HGL5 after supplementation of the extracts at a concentration range of 12.5 to 100 microg.ml-1. Qualitative as well as quantitative screening of polyphenols by high-performance liquid chromatography with diode-array detector (HPLC-DAD) analysis revealed rutin to be the most abundant polyphenol in both elderflower and elderberry extracts. In culture, neither elderflower nor elderberry extract caused any significant impact (p>0.05) in cell viability as studied by AlamarBlue assay in comparison to control. However, a dose-dependent stimulation of 17beta-estradiol release was detected by ELISA after supplementation of elderflower (at 50 microg.ml-1; p<0.01) and elderberry (at 100 microg.ml-1; p<0.05) extracts at higher doses used in the study. On the other hand, both elderflower and elderberry extracts stimulated the secretion of progesterone by HGL5 cells at a lower dose (12.5 microg.ml-1; p<0.05), as compared to control. Therefore, elderflower and elderberry extracts may have the potential to regulate steroidogenesis in ovarian cells.


Assuntos
Hormônios Esteroides Gonadais/metabolismo , Células da Granulosa/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Linhagem Celular , Feminino , Células da Granulosa/metabolismo , Humanos , Extratos Vegetais/química , Sambucus nigra/química
2.
Br J Sports Med ; 42(6): 472-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18390919

RESUMO

BACKGROUND: A number of studies have shown that proprioception training can reduce the risk of injuries in pivoting sports, but the mechanism is not clearly understood. AIM: To determine the contributing effects of propioception on knee joint position sense among team handball players. STUDY DESIGN: Prospective cohort study. METHODS: Two professional female handball teams were followed prospectively for the 2005-6 season. 20 players in the intervention team followed a prescribed proprioceptive training programme while 19 players in the control team did not have a specific propioceptive training programme. The coaches recorded all exposures of the individual players. The location and nature of injuries were recorded. Joint position sense (JPS) was measured by a goniometer on both knees in three angle intervals, testing each angle five times. Assessments were performed before and after the season by the same examiner for both teams. In the intervention team a third assessment was also performed during the season. Complete data were obtained for 15 subjects in the intervention team and 16 in the control team. Absolute error score, error of variation score and SEM were calculated and the results of the intervention and control teams were compared. RESULTS: The proprioception sensory function of the players in the intervention team was significantly improved between the assessments made at the start and the end of the season (mean (SD) absolute error 9.78-8.21 degrees (7.19-6.08 degrees ) vs 3.61-4.04 degrees (3.71-3.20 degrees ), p<0.05). No improvement was seen in the sensory function in the control team between the start and the end of the season (mean (SD) absolute error 6.31-6.22 degrees (6.12-3.59 degrees ) vs 6.13-6.69 degrees (7.46-6.49 degrees ), p>0.05). CONCLUSION: This is the first study to show that proprioception training improves the joint position sense in elite female handball players. This may explain the effect of neuromuscular training in reducing the injury rate.


Assuntos
Traumatismos do Joelho/prevenção & controle , Articulação do Joelho/fisiologia , Educação Física e Treinamento/métodos , Propriocepção/fisiologia , Adulto , Traumatismos em Atletas/fisiopatologia , Traumatismos em Atletas/prevenção & controle , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Traumatismos do Joelho/fisiopatologia , Estudos Prospectivos
3.
Anim Reprod Sci ; 104(2-4): 306-15, 2008 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-17374463

RESUMO

The present study attempted to evaluate the effect of different doses of lecirelin intramuscularly administered at the moment of insemination on parameters such as the conception rate, the total number of rabbits per litter, the number of stillborns per litter and the abortion rate in nulliparous and lactating crossbred rabbit does. The experiment was performed with 295 crossbred female rabbits Hyplus strain PS 19 that were housed in a rabbit farm. Six days before insemination, the light-dark cycles were as follows: 16-h light (70 lx and more):8-h dark, and all does were subcutaneously injected with 25 IU of eCG 48 h before insemination. The doses of lecirelin were as follows: 0.05, 0.1, 0.2, 0.3, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, and 4.0 microg/doe, and were tested in both nulliparous and lactating female does; the doses were applied at the moment of insemination. The conception rate in nulliparous does ranged significantly from 10.0% (0.05 microg) to 89.5% (1.5 microg). The conception rate in lactating does was the lowest at a dose of 0.05 microg (10.0%), as compared with the doses starting from 0.3 microg, and was confirmed statistically significant. The lowest number of rabbits per litter was found at a lecirelin dose of 0.1 microg (6.64). This finding was statistically significant, as compared with doses equal to or exceeding 0.3 microg. No statistical differences were found for doses ranging from 0.3 to 4.0 microg in nulliparous does (9.06 versus 10.29, respectively). The lowest number of rabbits per litter in lactating does was found at a dose of 0.05 microg (8.28) while the highest number of rabbits was detected at a dose of 4.0 microg (10.73), without statistically significant differences among individual doses. Generally, the number of rabbits per litter in lactating rabbit does was higher than that in nulliparous does (P<0.05). One negative finding is that abortions occurred in lactating does at the intramuscular application of a dose equal to or exceeding 1.5 microg, and in nulliparous does at a dose equal to or exceeding 2.0 microg.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Inseminação Artificial/veterinária , Indução da Ovulação/veterinária , Coelhos/fisiologia , Animais , Animais Recém-Nascidos , Relação Dose-Resposta a Droga , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/farmacologia , Injeções Subcutâneas/veterinária , Inseminação Artificial/métodos , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Masculino , Indução da Ovulação/métodos , Gravidez , Natimorto/veterinária
4.
Life Sci ; 79(9): 847-53, 2006 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-16616765

RESUMO

The brain uptake and brain to blood efflux transport of (14)C-GABA were studied in spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats using 20 min bilateral in situ brain perfusion in rats anesthetized using urethane. The volume of distribution (Vd) of (14)C-GABA into cerebrospinal fluid (CSF) and brain regions (cortex, diencephalon, cerebellum, and brain stem) was significantly greater in SHR than in the corresponding regions in WKY rats (p<0.05). The estimated Vd value of (14)C-GABA in CSF of SHR was 3.4 fold greater than that in WKY. Also compared to WKY, the Vd of (14)C-GABA into cerebellum and cortex of SHR was 15.3 fold and 19.4 fold greater, respectively. Although the study of blood-brain barrier (BBB) integrity using (3)H-mannitol revealed increased paracellular permeability at the brain capillaries of SHR when compared to WKY rats, this was found to be only partially responsible for the increased (14)C-GABA uptake. The study of brain to blood efflux transport of (14)C-GABA (after loading of brain with (14)C-GABA by vascular perfusion) revealed that the half-time of elimination was significantly shorter in SHR (5.35+/-0.66 min) than in WKY rats (14.83+/-1.94 min), (p<0.001). HPLC analysis revealed that GABA concentrations in brain extracts and CSF of SHR were similar to those in WKY rats (p>0.05). The faster efflux in SHR might be, at least partially, responsible to compensate for increased uptake of this neurotransmitter and to preserve the protective function of BBB towards GABA. The protective function of the BCSFB towards GABA appears to be also preserved, since systemic infusion of GABA within a wide range of administered doses (0.004-5.00 mg/kg) produced an increase in GABA CSF concentration from around 0.5 microM to only 11 microM, and the obtained pattern of CSF GABA concentrations under these conditions did not differ between SHR and WKY rats, as revealed by HPLC.


Assuntos
Barreira Hematoencefálica/fisiologia , Química Encefálica/fisiologia , Ácido gama-Aminobutírico/metabolismo , Animais , Transporte Biológico Ativo/fisiologia , Pressão Sanguínea/fisiologia , Cromatografia Líquida de Alta Pressão , Azul Evans , Feminino , Infusões Intravenosas , Masculino , Manitol/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Ácido gama-Aminobutírico/sangue , Ácido gama-Aminobutírico/líquido cefalorraquidiano
5.
Knee Surg Sports Traumatol Arthrosc ; 9(5): 307-12, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11685364

RESUMO

We present our technique for surgically treating Tossy III acromioclavicular joint dislocation, discuss the indications for various procedures, and evaluate our postoperative results. We operated on 17 patients suffering from chronic acromioclavicular instability after such dislocation using a modified Weaver-Dunn procedure, in which there is no lateral clavicular end resection, the coracoacromial ligament graft is sutured to the inferior part of the clavicle by transosseal sutures, and a Bosworth coracoclavicular screw is used to protect the graft postoperatively for 8 weeks. After a mean of 37 months we evaluated shoulder function by the Constant score and the subjective and radiological results. Mean Constant score was 91.9% (74-100%); it was 80-90% in 5 patients and above 90% in 11. One patient had screw loosing after the operation and suffered partial loss of reduction and discomfort during shoulder loading. All patients but one returned to work, and all but one have returned to their preoperative activity at the same level. Subjectively, there were 11 excellent and 6 good results. Compared to the contralateral uninjured side, radiography showed anatomical reposition in the vertical plane in 9 cases, slight loss of reduction in 6 (difference in the distance between the inferior border of the acromion and the clavicle is 2-4 mm), and partial loss of reduction in 2 (4-8 mm). We recommend the modified Weaver-Dunn procedure for surgical treatment of chronic, Tossy grade III acromioclavicular joint dislocations as it provides good functional and subjective results. Our modification is indicated mainly for young patients because posttraumatic arthrosis occurs more frequently in elderly patients, making clavicular end resection necessary.


Assuntos
Articulação Acromioclavicular/lesões , Articulação Acromioclavicular/cirurgia , Luxações Articulares/cirurgia , Procedimentos Ortopédicos , Adolescente , Adulto , Traumatismos em Atletas/cirurgia , Parafusos Ósseos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Autólogo
7.
Exp Brain Res ; 124(3): 273-80, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9989432

RESUMO

Galvanic vestibular stimulation serves to modulate the continuous firing level of the peripheral vestibular afferents. It has been shown that the application of sinusoidally varying, bipolar galvanic currents to the vestibular system can lead to sinusoidally varying postural sway. Our objective was to test the hypothesis that stochastic galvanic vestibular stimulation can lead to coherent stochastic postural sway. Bipolar binaural stochastic galvanic vestibular stimulation was applied to nine healthy young subjects. Three different stochastic vestibular stimulation signals, each with a different frequency content (0-1 Hz, 1-2 Hz, and 0-2 Hz), were used. The stimulation level (range 0.4-1.5 mA, peak to peak) was determined on an individual basis. Twenty 60-s trials were conducted on each subject - 15 stimulation trials (5 trials with each stimulation signal) and 5 control (no stimulation) trials. During the trials, subjects stood in a relaxed, upright position with their head facing forward. Postural sway was evaluated by using a force platform to measure the displacements of the center of pressure (COP) under each subject's feet. Cross-spectral measures were used to quantify the relationship between the applied stimulus and the resulting COP time series. We found significant coherency between the stochastic vestibular stimulation signal and the resulting mediolateral COP time series in the majority of trials in 8 of the 9 subjects tested. The coherency results for each stimulation signal were reproducible from trial to trial, and the highest degree of coherency was found for the 1- to 2-Hz stochastic vestibular stimulation signal. In general, for the nine subjects tested, we did not find consistent significant coherency between the stochastic vestibular stimulation signals and the anteroposterior COP time series. This work demonstrates that, in subjects who are facing forward, bipolar binaural stochastic galvanic stimulation of the vestibular system leads to coherent stochastic mediolateral postural sway, but it does not lead to coherent stochastic anteroposterior postural sway. Our finding that the coherency was highest for the 1- to 2-Hz stochastic vestibular stimulation signal may be due to the intrinsic dynamics of the quasi-static postural control system. In particular, it may result from the effects of the vestibular stimulus simply being superimposed upon the quiet-standing COP displacements. By utilizing stochastic stimulation signals, we ensured that the subjects could not predict a change in the vestibular stimulus. Thus, our findings indicate that subjects can act as "responders" to galvanic vestibular stimulation.


Assuntos
Equilíbrio Postural/fisiologia , Postura/fisiologia , Vestíbulo do Labirinto/fisiologia , Adolescente , Adulto , Estimulação Elétrica , Feminino , Humanos , Masculino , Processos Estocásticos
8.
Eur J Neurosci ; 10(5): 1590-607, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9751132

RESUMO

HDs racI Thrombin causes profound metabolic and morphological changes in cultured neural cells via activation of the thrombin receptor, also called protease-activated receptor 1 (PAR1). PAR1 mRNA is present in the rat brain, but the role of this receptor in the nervous system remains elusive. The expression of PAR1 and the potent thrombin inhibitor protease nexin-1 (PN-1) was investigated in the developing rat brain and spinal cord and after peripheral nerve lesion. As seen by in situ hybridization, the PAR1 mRNA signal in the late embryonic and early postnatal nervous system was widespread, but generally of low intensity whereas in the adult it was more pronounced and confined to particular neuronal cells. These include the mesencephalic dopaminergic neurons, several thalamic and brainstem nuclei, the mitral cells in the olfactory bulb and the Purkinje cells in the cerebellum. In the spinal cord, PAR1 mRNA was abundant in motoneurons and a particularly high expression was detected in the preganglionic neurons of the autonomic nervous system. High PAR1 mRNA expression was also found in the dorsal root ganglia. Interestingly, strong immunoreactivity for the protease inhibitor PN-1 was present in spinal motoneuron cell bodies, although its transcript was undetectable there. In response to sciatic nerve transection, the signal intensity of PAR1 mRNA as seen by Northern analysis increased in the proximal and the distal part of the lesioned nerve and in the denervated muscle, whereas the PN-1 mRNA signal strongly increased only in the distal part of the nerve but remained unchanged in the proximal part and in the muscle. After facial nerve transection, PAR1 mRNA expression substantially decreased in facial motoneurons. No PAR1 transcript was detected in reactive astrocytes. Similar to PAR1, PN-1 mRNA which was expressed in interneurons within the facial nucleus was also decreased following facial nerve transection.


Assuntos
Proteínas de Transporte/genética , Fenômenos Fisiológicos do Sistema Nervoso , RNA Mensageiro/biossíntese , Receptores de Trombina/genética , Inibidores de Serina Proteinase/genética , Serpinas/genética , Precursor de Proteína beta-Amiloide , Animais , Células Cultivadas , Desenvolvimento Embrionário e Fetal/fisiologia , Traumatismos do Nervo Facial , Sistema Nervoso/embriologia , Sistema Nervoso/crescimento & desenvolvimento , Nexinas de Proteases , Ratos , Ratos Sprague-Dawley , Receptor PAR-1 , Receptores de Superfície Celular , Nervo Isquiático/lesões , Medula Espinal/embriologia , Medula Espinal/fisiologia
9.
Artigo em Inglês | MEDLINE | ID: mdl-9604199

RESUMO

Complete rupture of the pectoralis major muscle, first described by Patissier in 1822, is a rare sports injury. Less than 100 cases have been reported in the literature since 1822. In this study, we describe our surgical technique and summarize our results and experience of the surgical treatment of pectoralis major rupture. Seven athletes (4 wrestlers, 2 handball players, 1 body-builder) were surgically treated in our department from 1981 to 1996. During the follow-up examination, five patients had excellent and two had good results, and six athletes could return to sports activity at their preoperative level. Among our patients we emphasize that of a wrestler, who had suffered an acute rupture, and 3 months after the surgery he won an Olympic gold medal. According to the literature and our experience, we suggest that only surgical repair of the acute pectoralis major rupture will result in both complete recovery and restoration of the full strength of the muscle, essential for active athletes.


Assuntos
Traumatismos em Atletas/cirurgia , Músculos Peitorais/lesões , Músculos Peitorais/cirurgia , Adulto , Humanos , Masculino , Ruptura/cirurgia , Procedimentos Cirúrgicos Operatórios/métodos , Luta Romana/lesões
10.
Artigo em Inglês | MEDLINE | ID: mdl-8884733

RESUMO

Recurrent anterior shoulder instability and the restoration of sports ability after surgery are common problems, especially among professional athletes. The purpose of this study was to evaluate the rate, level and time of returning to sports activity activity after Bankart procedure in anterior shoulder instability in high level athletes. From 1992-1994 61 patients suffering from recurrent anterior shoulder instability were operated on open Bankart procedure, 44 out of 61 were professional athletes. There were 7 handball, 7 basketball, 6 football, 2 waterpolo and 1 baseball player and 4 wrestlers, 2 weight-lifters, 2 boxers, 3 bicyclists, 2 motorists, 2 swimmers, 2 sailors, 2 kayakers and 2 skiers. The mean duration of instability was 19.1 months (3-72) before operation. 29 patients had posttraumatic recurrent anterior dislocation and 15 patients had posttraumatic anterior subluxations. The average number of redislocations was 4.4, ranging from 2 to 11. At the follow-up examination the patients were tested clinically for instability using the special score created by Walch and Duplay and the Constant functional score. We measured the strength of the rotator cuff by Kintrex isokinetic device from the 10th postoperative week. 35 out of 44 professional athletes could be followed-up. The average follow-up period was 14.2 months, from 6 to 31. 88% of the patients were able to return to sports participation, 66% on the previous level and 22% on a lower level. 12% of the patients finished their professional sports career. The mean rehabilitation period was 5.8 months, the average period of full restoration of sports ability was 9.3 months. Similar results were documented with the Constant score and the Walch-Duplay test (88% excellent or good, 12% fair). The main reason for the inability to continue sports activity was some pain during extreme abduction and external rotation of the arm and recurrent sensations of subluxation (3 cases). Based on the results of the follow-up examinations an early diagnosis is paramount followed by timely surgical intervention to restore anatomical integrity in proven cases of shoulder instability in professional athletes. The open Bankart procedure is preferred giving excellent functional results and providing good chances for the athletes to return to their previous sports level.


Assuntos
Traumatismos em Atletas/cirurgia , Instabilidade Articular/cirurgia , Lesões do Ombro , Adolescente , Adulto , Traumatismos em Atletas/fisiopatologia , Feminino , Seguimentos , Humanos , Instabilidade Articular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Recidiva , Rotação , Ombro/fisiopatologia
11.
Exp Brain Res ; 107(1): 145-50, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8751072

RESUMO

Stabilogram-diffusion analysis was used to examine how prolonged periods in microgravity affect the open-loop and closed-loop postural control mechanisms. It was hypothesized that following spaceflight: (1) the effective stochastic activity of the open-loop postural control schemes in astronauts is increased; (2) the effective stochastic activity and uncorrelated behavior, respectively, of the closed-loop postural control mechanisms in astronauts are increased; and (3) astronauts utilized open-loop postural controls schemes for shorter time intervals and smaller displacements. Four crew members and two alternates from the 14-day Spacelab Life Sciences 2 Mission were included in the study. Each subject was tested under eyes-open, quiet-standing conditions on multiple preflight and postflight days. The subjects' center-of-pressure trajectories were measured with a force platform and analyzed according to stabilogram-diffusion analysis. It was found that the effective stochastic activity of the open-loop postural control schemes in three of the four crew members was increased following spaceflight. This result is interpreted as an indication that there may be in-flight adaptations to higher-level descending postural control pathways, e.g., a postflight increase in the tonic activation of postural muscles. This change may also be the consequence of a compensatory (e.g., "stiffening") postural control strategy that is adopted by astronauts to account for general feeling of postflight unsteadiness. The crew members, as a group, did not exhibit any consistent preflight/postflight differences in the steady-state behavior of their closed-loop postural control mechanisms or in the functional interaction of their open-loop and closed-loop postural control mechanisms. These results are interpreted as indications that although there may be in-flight adaptations to the vestibular system and/or proprioceptive system, input from the visual system can compensate for such changes during undisturbed stance.


Assuntos
Hipogravidade , Postura/fisiologia , Voo Espacial , Vestíbulo do Labirinto/fisiologia , Humanos , Propriocepção/fisiologia , Fatores de Tempo
13.
J Neurosci Res ; 37(2): 256-70, 1994 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8151733

RESUMO

Glia-derived nexin/protease nexin-1 (GDN/PN-1) is a serine protease inhibitor that is secreted by glial cells and fibroblasts in culture. In the adult mammalian nervous system it has been shown to be expressed in the olfactory system and by some glial cells in response to neuronal injury. In situ hybridization and immunocytochemical studies were performed to identify the structures expressing GDN/PN-1 in the developing and adult rat brain. In contrast to a transient widespread expression during pre- and postnatal development, some brain structures constitutively express GDN/PN-1. These include the olfactory nerve layer of the olfactory bulb, basal forebrain, striatum, pyramidal neurons of layer V in the cortex, thalamic nuclei, pars compacta of the substantia nigra, inferior and superior colliculi, and deep cerebellar nuclei. All of these parts, excluding the olfactory nerve layer, are characterized by a high neuronal cell density. Neurons in these regions were immunoreactive for GDN/PN-1. Furthermore GDN/PN-1 expression in cell lines showed that the active protein was synthesized and secreted from B104 but not from NB2a neuroblastoma cells. Although GDN/PN-1 has only been reported to be synthesized by glia, the results presented here demonstrate that in addition, a subset of neurons express this protease inhibitor.


Assuntos
Química Encefálica/fisiologia , Proteínas de Transporte/biossíntese , Neurônios/metabolismo , Precursor de Proteína beta-Amiloide , Animais , Animais Recém-Nascidos , Northern Blotting , Encéfalo/citologia , Proteínas de Transporte/imunologia , Eletroforese em Gel de Poliacrilamida , Immunoblotting , Imuno-Histoquímica , Hibridização In Situ , Camundongos , Proteínas do Tecido Nervoso/biossíntese , Neuroblastoma/metabolismo , Nexinas de Proteases , RNA Mensageiro/biossíntese , Ratos , Receptores de Superfície Celular , Células Tumorais Cultivadas
14.
Ontogenez ; 24(2): 62-9, 1993.
Artigo em Russo | MEDLINE | ID: mdl-8488013

RESUMO

The effect of methylazoxymethanol (MAM), an antimitotic drug, on granule and Purkinje cells of the rat cerebellum was studied. MAM was injected subcutaneously into ICR mice on day 5 after birth. The number of nucleoli and DNA content in nuclei of cerebellar neurons were determined 2 and 12 days after the injection. The number of nucleoli served as a criterion of maturity of neurons. On day 2 after MAM administration the proportion of Purkinje cells containing a smaller number of nucleoli increased suggesting a direct effect of MAM on maturation of Purkinje neurons. On day 12 no difference in the number of nucleoli was found between experimental and control animals but the number of granule cells containing multiple nucleoli increased significantly. The latter suggests that the studied cell population was supplemented with less mature cells. As a result, development of Purkinje and granule cells is desynchronized and that appears to determine the secondary effect of MAM on Purkinje cell differentiation.


Assuntos
Acetato de Metilazoximetanol/farmacologia , Células de Purkinje/efeitos dos fármacos , Envelhecimento/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Nucléolo Celular/efeitos dos fármacos , Nucléolo Celular/ultraestrutura , Núcleo Celular/química , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Citofotometria , DNA/análise , DNA/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos ICR , Células de Purkinje/citologia
16.
Neurosci Lett ; 141(2): 177-80, 1992 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-1436632

RESUMO

We report the presence of spontaneous hemorrhages in the brain of normal neonatal rats. The quantitative evaluation showed that the hemorrhaging was most frequent in 4- to 5-day-old rats. Nearly all the lesions were found in the cerebral cortex of the lateral part of the forebrain hemisphere, particularly in the middle cortical layers. Their average incidence amounted to 6.71 +/- 2.95 per six 5-microns sections from 5-day-old rats. The lesions were nearly absent in the newborn and 7-day-old animals. We suggest that vascular wall immaturity and some extravascular factors, like developmental increase of blood pressure, may account for the perinatal hemorrhaging.


Assuntos
Córtex Cerebral/irrigação sanguínea , Hemorragia Cerebral/etiologia , Animais , Animais Recém-Nascidos , Córtex Cerebral/patologia , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/patologia , Incidência , Ratos
17.
Reprod Toxicol ; 6(4): 367-74, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1521011

RESUMO

Twenty five psychotropic drugs were ranked according to the embryotoxicity dose ranges estimated by the Chick Embryotoxicity Screening Test (CHEST). The chick results were compared with some data for common laboratory mammals. In 17 psychotropic drugs a deleterious dose-dependent effect upon the embryonic cardiovascular system was disclosed, terminating in immediate cardiac arrest.


Assuntos
Embrião de Mamíferos/efeitos dos fármacos , Psicotrópicos/toxicidade , Teratogênicos/toxicidade , Animais , Sistema Cardiovascular/efeitos dos fármacos , Embrião de Galinha , Feminino , Parada Cardíaca/induzido quimicamente , Parada Cardíaca/fisiopatologia , Camundongos , Gravidez , Coelhos , Ratos
18.
Neuropharmacology ; 28(6): 557-61, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2547179

RESUMO

The potency of nootropic drugs to protect cell proteins and lipids against free radical attack was studied. In an in vitro system, generating hydroxyl radicals by a Fenton-type reaction, the soluble proteins (bovine serum albumin and cytosol protein from brain) were quickly insolubilized and precipitated. Pyritinol (and tamitinol) exhibited the best protection against insolubilization of protein while centrophenoxine (meclophenoxate) and its dimethylaminoethanol moiety were less effective, piracetam (and oxiracetam) being without effect. The lipid peroxidation induced by free radicals from cyclic redox reactions of iron-ascorbate was not influenced by pyritinol, indicating the selectivity of its scavenger action. The efficient scavenging of hydroxyl radicals by pyritinol was confirmed by electron spin resonance spectroscopy measurement of hydroxyl radicals entrapped by spin trap. Millimolar concentrations of pyritinol competitively decreased the formation of spin adducts. The results suggest that the protective effect of pyritinol against free-radical induced derangement of cell proteins may be an important part of its antirheumatic, as well as nootropic, action.


Assuntos
Proteínas/análise , Psicotrópicos/farmacologia , Piridinas/farmacologia , Piritioxina/farmacologia , Animais , Ácido Ascórbico/farmacologia , Química Encefálica/efeitos dos fármacos , Óxidos N-Cíclicos , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Peroxidação de Lipídeos/efeitos dos fármacos , Proteínas do Tecido Nervoso , Ratos , Marcadores de Spin
20.
Neuropharmacology ; 28(1): 89-97, 1989 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2927582

RESUMO

Drugs administered during the perinatal period reach the developing organism at the vulnerable stage of intensive brain histogenesis and cytodifferentiation. They may interfere with the programme of developmental processes in the brain and lead to disturbances at the cellular/subcellular level and to biochemical alterations. These abnormalities form the basis for the functional pathology which becomes apparent gradually during maturation or even in adulthood as neuropsycho-behavioural deviations. A model experimental study in rats was carried out with synthetic glucocorticoids, which are widely used in obstetrics and neonatology for the prevention and treatment of neonatal idiopathic respiratory distress syndrome. As the developmental stage of the brain of the human foetus in late pregnancy closely resembles the ontogenetic phases of the brain of the rat in the early postnatal period, the neonate rat was taken as a model. The administration of dexamethasone to 7-day-old rats resulted in significant depletion of glucocorticoid receptors from the cytosol of the brain in a dose-dependent manner, beginning with the dose of 0.04 mg/kg (s.c.), i.e. a dose one order lower than the clinical dose used in obstetrics (0.4-0.5 mg/kg). Long-term follow-up of a single neonatal injection of dexamethasone (0.2 or 1 mg/kg s.c. on postnatal day 7) revealed an acceleration of some developmental landmarks in the preweaning period (incisor eruption, eye opening, motor skill) on the one hand, but a retardation of body growth and vaginal opening on the other hand. Adult animals exhibited a deficit in motor co-ordination, behavioural deviations (hyperactivity with stereotypy, decreased adaptability, increased emotional reactivity) and disturbances in reproduction in both males and females.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Encéfalo/efeitos dos fármacos , Dexametasona/efeitos adversos , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Química Encefálica , Aprendizagem/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Reforço Psicológico , Reprodução/efeitos dos fármacos
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