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1.
J Endocrinol ; 261(3)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38593833

RESUMO

The mouse estrous cycle is divided into four stages: proestrus (P), estrus (E), metestrus (M), and diestrus (D). The estrous cycle affects reproductive hormone levels in a wide variety of tissues. Therefore, to obtain reliable results from female mice, it is important to know the estrous cycle stage during sampling. The stage can be analyzed from a vaginal smear under a microscope. However, it is time-consuming, and the results vary between evaluators. Here, we present an accurate and reproducible method for staging the mouse estrous cycle in digital whole-slide images (WSIs) of vaginal smears. We developed a model using a deep convolutional neural network (CNN) in a cloud-based platform, Aiforia Create. The CNN was trained by supervised pixel-level multiclass semantic segmentation of image features from 171 hematoxylin-stained samples. The model was validated by comparing the results obtained by CNN with those of four independent researchers. The validation data included three separate studies comprising altogether 148 slides. The total agreement attested by the Fleiss kappa value between the validators and the CNN was excellent (0.75), and when D, E, and P were analyzed separately, the kappa values were 0.89, 0.79, and 0.74, respectively. The M stage is short and not well defined by the researchers. Thus, identification of the M stage by the CNN was challenging due to the lack of proper ground truth, and the kappa value was 0.26. We conclude that our model is reliable and effective for classifying the estrous cycle stages in female mice.


Assuntos
Aprendizado Profundo , Ciclo Estral , Animais , Feminino , Ciclo Estral/fisiologia , Camundongos , Esfregaço Vaginal/métodos , Redes Neurais de Computação , Processamento de Imagem Assistida por Computador/métodos , Reprodutibilidade dos Testes
2.
Aquat Toxicol ; 48(2-3): 265-274, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10686331

RESUMO

The 21-hydroxylation of 17alpha-hydroxyprogesterone is one step in the biosynthesis of corticosteroids. Both 7 days of handling-induced stress and 7 weeks of food deprivation significantly elevated head kidney microsomal 17alpha-hydroxyprogesterone 21-hydroxylase activity in juvenile rainbow trout. The increased 21-hydroxylase activity was not paralleled by changes in plasma cortisol levels induced by handling stress whereas food deprivation for 3 and 7 weeks increased both 21-hydroxylase activity and plasma cortisol levels significantly. Food deprivation in rainbow trout affected detoxification enzyme activities, namely glutathione-S-transferase (GST), uridine-di-phosphate glucuronosyltransferase (UGT) and glutathione reductase (GR) activities in the liver. Together our observations suggest that experimental conditions can affect experimental results, especially the values of parameters like GST, UGT and GR. Furthermore, alterations in the metabolic state of the liver caused by stress or food deprivation can alter the balance between detoxification enzymes in rainbow trout liver.

4.
Acta Neurol Scand ; 95(6): 321-30, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9395431

RESUMO

The characteristics of patients suffering from drug resistant epilepsy, including the results of the preoperative evaluation and epilepsy surgery were retrospectively analyzed in a Swedish multicenter 10-year cohort of children and adults. Altogether 152 patients (65 children and 87 adults) treated during the period 1980-1990 in three epilepsy centers were included and followed-up 2 years after surgery. Median age at onset of seizures was 4 years for the children and 12 years for the adults. A localization related epilepsy was present in 85% of the children and in 95% of the adults. The mean number of seizure types in the children was 1.7 (range 1-4) and in the adults 1.8 (range 1-4). The median monthly seizure frequency was 52 and 15 for children and adults respectively. Resective surgery was performed in 143 cases (94 temporal, 31 extratemporal, 9 multilobar and 9 major resection procedures) and palliative procedures in 16 cases (13 callosotomies and 3 stereotactic amygdalotomies). Postoperative neurological deficits were detected in 9% of the patients after temporal lobe resections and in 15% of the patients after extratemporal and multilobar resection procedures. Two years after resective surgery 53% of the children and 49% of the adults were seizure free. Another 25% of the patients had a more than 50% reduction of seizure frequency. In the postoperative non seizure free group of patients there was a negative correlation between decrease in weighted seizure severity and decrease in seizure frequency. This finding stresses the need for including other parameters than seizure frequency when evaluating the outcome of epilepsy surgery.


Assuntos
Córtex Cerebral/cirurgia , Descorticação Cerebral , Epilepsia/cirurgia , Avaliação de Resultados em Cuidados de Saúde , Índice de Gravidade de Doença , Adolescente , Adulto , Fatores Etários , Idade de Início , Anticonvulsivantes/uso terapêutico , Córtex Cerebral/fisiopatologia , Descorticação Cerebral/efeitos adversos , Descorticação Cerebral/métodos , Descorticação Cerebral/normas , Criança , Pré-Escolar , Estudos de Coortes , Resistência a Medicamentos , Epilepsia/classificação , Epilepsia/complicações , Epilepsia/tratamento farmacológico , Feminino , Seguimentos , Lobo Frontal/cirurgia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde/normas , Estudos Retrospectivos , Suécia , Lobo Temporal/fisiopatologia , Lobo Temporal/cirurgia
6.
Eur J Oral Sci ; 105(1): 59-66, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9085030

RESUMO

The effect of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) on bone healing was examined in calvarial defects in rabbits. Bicortical circular (critical size) defects were prepared in the calvarial bone of 16 rabbits. The defects were closed on the dural side and covered externally with expanded polytetrafluoroethylene membranes to prevent interference with osteogenesis within the defect by the surrounding tissue and to keep the growth factor in place. A single dose of methylcellulose gel (4.4%) with (n = 8) or without rhPDGF-BB (50 micrograms/ml) (n = 8) was applied to the defects, and the bone formation was evaluated after 8 weeks. Healing of defects in both groups was characterized by the presence of newly formed bone along the edges of the original defect and by a central area of fibrous connective tissue. The newly formed bone in the rhPDGF-BB treated defects had a trabecular structure; in contrast, a more compact structure was found in the control defects. In the rhPDGF-BB-treated defects, the bone ingrowth was 51.8 +/- 7.1% compared to 30.5 +/- 3.3% in the control defects. Furthermore, the amount of mineralized tissue was increased 112% in the rhPDGF-BB group. The amount of bone marrow was increased 75% in the rhPDGF-BB-treated defect. The porosity of cortical lamella in the newly formed bone was 84% higher in the rhPDGF-BB-treated defects compared to the control. These results show that administration of a single dose of rhPDGF-BB stimulates bone formation in critical size calvarial defects.


Assuntos
Substâncias de Crescimento/uso terapêutico , Osteogênese/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/uso terapêutico , Crânio/efeitos dos fármacos , Animais , Becaplermina , Doenças Ósseas/tratamento farmacológico , Doenças Ósseas/patologia , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Calcificação Fisiológica/efeitos dos fármacos , Tecido Conjuntivo/efeitos dos fármacos , Tecido Conjuntivo/patologia , Método Duplo-Cego , Feminino , Géis , Substâncias de Crescimento/administração & dosagem , Humanos , Processamento de Imagem Assistida por Computador , Membranas Artificiais , Metilcelulose , Excipientes Farmacêuticos , Fator de Crescimento Derivado de Plaquetas/administração & dosagem , Politetrafluoretileno , Porosidade , Proteínas Proto-Oncogênicas c-sis , Coelhos , Distribuição Aleatória , Proteínas Recombinantes , Crânio/patologia , Cicatrização/efeitos dos fármacos
7.
Neurosci Res ; 22(1): 51-5, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7792082

RESUMO

The dipole tracing (DT) method estimates the position and vector dipole moment of an equivalent current dipole by minimizing the mean squared error of the dipole potentials at the surface electrode positions. In the scalp-skull-brain/DT (SSB/DT) method, which we have developed, the head model consists of three compartments of uniform conductors corresponding to the scalp, skull and brain. The accuracy of the calculations are mainly dependent on the ratios of the conductivities of the three compartments. The best result was obtained with the conductivity ratios of 1:1/80:1 for the scalp, skull and brain compartments, respectively.


Assuntos
Encéfalo/fisiologia , Couro Cabeludo/fisiologia , Crânio/fisiologia , Encéfalo/anatomia & histologia , Condutividade Elétrica , Estimulação Elétrica , Epilepsia/patologia , Humanos , Modelos Anatômicos , Couro Cabeludo/anatomia & histologia , Crânio/anatomia & histologia
8.
Electroencephalogr Clin Neurophysiol ; 91(5): 374-82, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7525234

RESUMO

Using a realistic, 3-shell head model including the scalp (S), skull (S) and brain (B) with conductivity ratios of 1:1/80:1, respectively, the electrical activity in the human brain recorded by conventional electroencephalography was approximated by 1 or 2 equivalent current dipoles. The dipole locations and vector moments were estimated by minimizing the squared difference between the potentials actually recorded from the scalp and those theoretically calculated from the equivalent dipoles. The validity of this dipole tracing method (the DT of the SSB head model) was tested in patients with focal epileptic seizures undergoing presurgical evaluation with intracranial subdural strip electrodes. Weak currents were passed through 1 or 2 pairs of subdural electrodes to create artificial dipoles. The dipole estimations correctly distinguished between single and double generator sources, but there were certain dislocations of the calculated dipoles. The average error of dislocation was found to be 8.5 mm for the 1-dipole model. That for the 2-dipole model was 6 mm for one of the components and 18 mm for the other. It was concluded that the DT method of the SSB head model can be a valuable clinical tool in 3-dimensional localization of focal epileptic discharges in the human brain.


Assuntos
Mapeamento Encefálico/instrumentação , Encéfalo/fisiologia , Modelos Neurológicos , Couro Cabeludo/fisiologia , Crânio/fisiologia , Eletrofisiologia , Humanos
9.
J Periodontol ; 65(5): 373-8, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8046552

RESUMO

An enhanced formation of bone, dentin, and collagen fibers in periodontal wounds after application of polypeptide growth factors has recently been reported. However, the complex environment in vivo makes it impossible to determine the specific effects of growth factors on various cells involved in the wound-healing process. We have therefore investigated the mitogenic and morphogenic effects of recombinant epidermal growth factor (rEGF), natural platelet-derived growth factor (nPDGF), and natural fibroblast growth factor (nFGF) on periodontal ligament fibroblast-like cells. A cell line was established from rat PDL tissue. The cell line was characterized according to morphology, growth pattern, cytoskeletal proteins, and growth kinetics. The mitogenic effect of growth factors was assessed by incorporation of [3H]thymidine in the cellular DNA for 4 hours. Differences between groups of observations were assessed by the Student t-test. The morphogenic effects of growth factors were described with respect to growth pattern, cell orientation, and cell and nucleus form after a random photographic recording. The fibroblast-like cell type and the non-transformed phenotype of the cell line have been identified by the presence of parameters considered to be characteristic of a normal fibroblast-like cell line. The morphogenic analysis of both experimental and control cultures showed a monolayer of adherent cells with spindle or stellate morphology, a random alignment and round or elongated nuclei. Incorporation of [3H]-thymidine was increased in a dose-dependent manner by all growth factors. Maximal effect on the DNA synthesis was: rEGF, 131%; nPDGF, 274%; and nFGF, 182%.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
DNA/biossíntese , Fator de Crescimento Epidérmico/farmacologia , Fatores de Crescimento de Fibroblastos/farmacologia , Fibroblastos/metabolismo , Ligamento Periodontal/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Animais , Bovinos , Divisão Celular , Linhagem Celular , Fibroblastos/citologia , Humanos , Ligamento Periodontal/citologia , Ratos
10.
Eur J Popul ; 10(2): 143-73, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-12288064

RESUMO

"Retrospective survey data are used to estimate the effect of various factors on the transitions to first marriage or first cohabitation among single Norwegian men and women born in 1945 and 1960. A high educational level is not found to reduce marriage intensities for women, although educational enrollment appears to be less compatible with marriage for women than men. The effect of employment varies according to prevailing sex-role expectations. The data support the assumption that modern cohabitation developed from two socially opposite origins, the educated elite and the working class. A social value dimension is assumed to have a major effect upon the present-day choice between marriage and cohabitation." (SUMMARY IN FRE)


Assuntos
Escolaridade , Emprego , Estado Civil , Casamento , Fatores Sexuais , Classe Social , Valores Sociais , Comportamento , Demografia , Países Desenvolvidos , Economia , Europa (Continente) , Noruega , População , Características da População , Psicologia , Países Escandinavos e Nórdicos , Comportamento Social , Fatores Socioeconômicos
12.
J Periodontol ; 63(12): 960-8, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1474468

RESUMO

Repopulation of the detached root surface by cells from the periodontal ligament (PDL) is a prerequisite for new attachment formation. Stimulation of PDL-cell growth may therefore serve as an essential method to enhance formation of new attachment. Studies have demonstrated that insulin-like growth factor-I (IGF-I) has a mitogenic effect on fibroblasts originating from various connective tissues and cell-lines. Further, human growth hormone (hGH) is known to regulate the plasma concentration of IGF-I and to mediate cellular biological effects. In the present study we examined the effect of IGF-I and hGH on morphology, growth pattern, and DNA synthesis. The expression of IGF-I and hGH receptors on the surface of cultured PDL fibroblasts is also described. A primary fibroblastic cell line was established from rat PDL tissue, and blind, photographic recordings of morphology and growth pattern, as well as incorporation of [3H]thymidine in cellular DNA, was carried out in the presence and absence of IGF-I and hGH. The presence of specific membrane receptors was investigated by binding of [125I]IGF-I and [125I]hGH. The analysis of photographs showed that IGF-I and hGH had no effect on morphology and growth pattern. Incorporation of 3H-thymidine, however, was increased in a dose-dependent manner by IGF-I, whereas hGH alone or in combination with IGF-I produced no dose-dependent response. Maximum effect (% of control) on DNA synthesis was 176% for IGF-I and 91% for hGH.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
DNA/biossíntese , Fibroblastos/efeitos dos fármacos , Hormônio do Crescimento/farmacologia , Fator de Crescimento Insulin-Like I/farmacologia , Ligamento Periodontal/efeitos dos fármacos , Receptor IGF Tipo 1/efeitos dos fármacos , Receptores da Somatotropina/efeitos dos fármacos , Animais , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Tamanho Celular/efeitos dos fármacos , Citoesqueleto/química , DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fibroblastos/química , Fibroblastos/citologia , Fibroblastos/metabolismo , Hormônio do Crescimento/administração & dosagem , Fator de Crescimento Insulin-Like I/administração & dosagem , Radioisótopos do Iodo , Ligamento Periodontal/química , Ligamento Periodontal/citologia , Ligamento Periodontal/metabolismo , Ratos , Ratos Endogâmicos , Receptor IGF Tipo 1/metabolismo , Receptores da Somatotropina/metabolismo , Timidina/metabolismo , Trítio
13.
Neurosci Lett ; 113(2): 181-6, 1990 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-2198500

RESUMO

A new dipole tracing method, based on a realistic head model, was used to determine dipole locations and vector moments of interictal convexity sharp waves recorded (with conventional EEG technique) from the right fronto-temporal region in a patient with partial complex seizures. When the dipole locations in the head model were compared to MRI scans, the majority of the sharp wave dipoles were found to be located in the right hippocampal area. For individual sharp waves, the hippocampal dipoles moved along tracks corresponding to the vector moment directions, suggesting that the electrical sources of the convexity sharp waves were somato-dendritic currents which spread rapidly from one neuron group to the next in the hippocampal area. Previous long-term subdural recording had shown seizure onset in this area. After right-sided anterior temporal lobectomy including the hippocampus the patient has been seizure-free for three months.


Assuntos
Diagnóstico por Computador , Eletroencefalografia , Eletrofisiologia/métodos , Epilepsia do Lobo Temporal/fisiopatologia , Adulto , Feminino , Humanos
15.
Presse Med ; 15(31): 1520-3, 1986 Sep 25.
Artigo em Francês | MEDLINE | ID: mdl-2947092

RESUMO

Injectable Ginkgo biloba extract, administered intravenously to rabbits, suppressed the vasospasm induced by the topic application of autologous serum on brain surface. This effect was dose-dependent as for as the normalization of the arterial diameter and duration of spasm were concerned. In animals previously treated with oral Ginkgo biloba extract, the almost complete disappearance of spasm was observed at intervals of time similar to those observed after intravenous injection.


Assuntos
Ataque Isquêmico Transitório/tratamento farmacológico , Plantas Medicinais , Árvores , Administração Oral , Animais , Arteríolas/efeitos dos fármacos , Encéfalo/irrigação sanguínea , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Feminino , Soros Imunes/farmacologia , Injeções Intravenosas , Ataque Isquêmico Transitório/induzido quimicamente , Masculino , Extratos Vegetais/uso terapêutico , Coelhos , Fatores de Tempo
16.
Scand J Work Environ Health ; 11(4): 265-9, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2997912

RESUMO

Forty-seven copper smelter workers, exposed to airborne arsenic for 8-40 years, were examined clinically with electromyography, and the motor and sensory conduction velocities in their arms and legs were determined. Fifty age-matched industrial workers not exposed to arsenic formed a reference group. The level of arsenic in the air at the smeltery was estimated to be below 500 micrograms/m3 before 1975 and approximately 50 micrograms/m3 thereafter. Urine analyses of arsenic showed a mean value of 71 micrograms/l (1 mumol/l) in the exposed group; this value is lower than that found in earlier studies reporting clinically detectable neuropathy. Only minor neurological and electromyographic abnormalities were found. A slightly reduced nerve conduction velocity in two or more peripheral nerves was more common among the arsenic workers than the referents, and a statistically significant correlation between cumulative exposure to arsenic and reduced nerve conduction velocity in three peripheral motor nerves was found. This occurrence was interpreted as a sign of slight subclinical neuropathy. In conclusion the risk of clinically significant neuropathy is small when exposure is kept below 50 micrograms/m3 in workroom air. The subclinical findings may be of interest in relation to the prevention of early adverse health effects from arsenic exposure.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Arsênio/efeitos adversos , Metalurgia , Doenças Profissionais/induzido quimicamente , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Adulto , Idoso , Eletromiografia , Humanos , Masculino , Pessoa de Meia-Idade , Condução Nervosa/efeitos dos fármacos , Suécia , Fatores de Tempo
17.
Electroencephalogr Clin Neurophysiol ; 61(2): 138-40, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2410223

RESUMO

Potentials from the sensory root of the trigeminal nerve in the cerebello-pontine angle, evoked by electrical stimulation of the different trigeminal divisions, were recorded during neurosurgical operations. Two components of the compound action potential could be distinguished: one early with large amplitude and one late with small amplitude. It is concluded that the two components represent activity in A alpha and A delta fibers respectively.


Assuntos
Neuroma Acústico/fisiopatologia , Nervo Trigêmeo/fisiopatologia , Neuralgia do Trigêmeo/fisiopatologia , Potenciais de Ação , Adulto , Idoso , Estimulação Elétrica , Humanos , Pessoa de Meia-Idade
18.
Appl Neurophysiol ; 48(1-6): 351-7, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-3879796

RESUMO

Phrenic nerve stimulators (diaphragm pacers) were implanted in 16 patients with partial or total respiratory insufficiency due to high cervical medullary lesions and brain stem lesions (14 cases) or central hypoventilation syndrome (2 cases). At 5-72 months' follow-up (M = 35) 12 patients are entirely independent of conventional respirator, 2 of them after 8 years of total respirator dependency. Two patients are dead and the final 2 cases had limited help from diaphragm pacing.


Assuntos
Terapia por Estimulação Elétrica/métodos , Nervo Frênico , Paralisia Respiratória/terapia , Adolescente , Adulto , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Nervo Frênico/fisiopatologia , Paralisia Respiratória/fisiopatologia
19.
Acta Neurol Scand ; 70(6): 423-31, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6516791

RESUMO

Bilateral intracarotidal Amytal (amobarbital) tests for evaluation of speech and memory function were performed during preoperative evaluation of 30 patients with drug-resistant epilepsy. In 8 of these patients (16 tests), having partial complex epilepsy, EEG was recorded with depth electrodes, implanted bilaterally in anterior mesial temporal structures. The EEGs during 13 tests could be quantified with regard to spike activity. A rapid increase in spike frequency was observed ipsilateral to the injection in all tests but one. No seizure activity or clinical seizures were provoked. This previously unnoticed effect of amobarbital could be due to a direct excitatory effect of the drug on epileptic temporal neurones or, alternatively, to a release of interictal inhibition, exerted upon these neurons by other structures. In 4 patients, the effect was compared with that of methohexital, another barbiturate known to have excitatory effects upon epileptic activity.


Assuntos
Amobarbital/farmacologia , Encéfalo/efeitos dos fármacos , Eletroencefalografia , Epilepsia/fisiopatologia , Potenciais de Ação/efeitos dos fármacos , Adolescente , Adulto , Encéfalo/fisiopatologia , Eletrodos , Feminino , Humanos , Masculino , Metoexital/farmacologia , Pessoa de Meia-Idade
20.
Neurochirurgia (Stuttg) ; 27(4): 115-6, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6332993

RESUMO

The authors implanted a diaphragm pacer in a 71-year-old man who had suffered for two years from continuous hiccup of unknown cause with resulting insomnia. Preoperative transcutaneous stimulation of the phrenic nerves in the neck resulted in diaphragm contractions but did not affect his hiccup. Postoperatively, the patient was free of symptoms for two weeks. Electrophrenic stimulation was then initiated and after three days his hiccup disappeared again. After a ten day period without stimulation his hiccup recurred. For ten months the patient has suffered from hiccup only in the day time during which time he has also used the pacer. With a few exceptions he has been free of symptoms and without pacing during the night, which enables him to sleep normally. The effect of phrenic nerve stimulation on hiccup could be due to interference with the abnormal activation of the phrenic nerve, whatever its cause.


Assuntos
Terapia por Estimulação Elétrica/métodos , Soluço/terapia , Nervo Frênico , Idoso , Terapia por Estimulação Elétrica/instrumentação , Soluço/fisiopatologia , Humanos , Masculino , Nervo Frênico/fisiopatologia
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