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1.
Vet Surg ; 45(6): 782-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27399196

RESUMO

OBJECTIVE: To report the signalment, presenting clinical signs, surgical complications, histologic diagnosis, postoperative complications, and outcome of dogs and cats undergoing pneumonectomy. STUDY DESIGN: Retrospective case series; multicenter study. ANIMALS: Client-owned dogs (n=17) and cats (n=10). METHODS: Signalment, clinical signs, side affected, surgical data, preoperative diagnostic tests (including complete blood count, serum biochemistry, cytologic diagnosis, chest radiographs, and computed tomography), histologic diagnosis, surgical complications, adjunctive therapy, and date and cause of death were collected from records of dogs and cats that underwent pneumonectomy. Survival estimates and complication were assessed. RESULTS: Seventeen animals had a left-sided pneumonectomy performed (12 dogs, 5 cats) and 10 animals had a right-sided pneumonectomy (5 dogs, 5 cats). Fourteen animals were diagnosed with neoplasia (52%). The overall incidence of complications for dogs and cats were 76 and 80%, respectively, with major complications in 41 and 50%, respectively. Respiratory complications (persistent pleural effusion, oxygen dependence, persistent increased respiratory rate, or coughing) were the most frequent complications. No animals died or were euthanatized intraoperative or within the first 24 hours postoperative. One dog (6%) and 2 cats (20%) died, or were euthanatized in the first 2 weeks postoperative. CONCLUSION: Based on this case series, right and left pneumonectomy can be performed with low perioperative mortality in dogs and cats, with some animals experiencing prolonged survival.


Assuntos
Doenças do Gato/cirurgia , Doenças do Cão/cirurgia , Pneumonectomia/veterinária , Animais , Gatos , Cães , Feminino , Masculino , Derrame Pleural/cirurgia , Derrame Pleural/veterinária , Complicações Pós-Operatórias/veterinária , Radiografia Torácica , Estudos Retrospectivos , Resultado do Tratamento
2.
Osteoarthritis Cartilage ; 22(7): 904-11, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24836210

RESUMO

OBJECTIVE: To examine the feasibility of a 10-week gait modification program in people with medial tibiofemoral knee osteoarthritis (OA), and to assess changes in clinical and biomechanical outcomes. DESIGN: Fifteen people with medial knee OA completed 10 weeks of gait modification focusing on increasing toe-out angle during stance 10° compared to their self-selected angle measured at baseline. In addition to adherence and performance difficulty outcomes, knee joint symptoms (Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale and total score, numerical rating scale (NRS) of pain), and knee joint loading during gait (late stance peak knee adduction moment (KAM)) were assessed. RESULTS: Participants were able to perform the toe-out gait modification program with minimal to moderate difficulty, and exhibited significant increases in self-selected toe-out angle during walking (P < 0.001). Joint discomfort was reported by five participants (33%) in the hip or knee joints, though none lasted longer than 2 weeks. Participants reported statistically significant reductions in WOMAC pain (P = 0.02), NRS pain (P < 0.001), WOMAC total score (P = 0.02), and late stance KAM (P = 0.04). CONCLUSIONS: These preliminary findings suggest that toe-out gait modification is feasible in people with medial compartment knee OA. Preliminary changes in clinical and biomechanical outcomes provide the impetus for conducting larger scale studies of gait modification in people with knee OA to confirm these findings.


Assuntos
Marcha/fisiologia , Osteoartrite do Joelho/fisiopatologia , Osteoartrite do Joelho/terapia , Modalidades de Fisioterapia , Dedos do Pé/fisiologia , Idoso , Fenômenos Biomecânicos/fisiologia , Estudos de Viabilidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Dor/reabilitação , Medição da Dor , Projetos Piloto , Resultado do Tratamento , Caminhada/fisiologia
3.
Osteoarthritis Cartilage ; 22(2): 203-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24333292

RESUMO

OBJECTIVE: To compare the energy expenditure of increased lateral trunk lean walking - a suggested method of reducing medial compartment knee joint load - compared to normal walking in a population of older adults with medial knee osteoarthritis (OA). METHOD: Participants completed two randomly-presented treadmill walking conditions: 15 min of normal walking or walking with ten degrees of peak lateral trunk lean. Lateral trunk lean angle was displayed in front of the participant in real-time during treadmill conditions. Energy expenditure (VO2 and METs), heart rate (HR), peak lateral trunk lean angle, knee pain and perceived exertion were measured and differences between conditions were compared using paired t-tests. RESULTS: Twelve participants (five males, mean (standard deviation (SD)) age 64.1 (9.4) years, body mass index (BMI) 28.3 (4.9) kg/m²) participated. All measures were significantly elevated in the lateral trunk lean condition (P < 0.008), except for knee pain (P = 0.22). Oxygen consumption (VO2) was, on average 9.5% (95% CI 4.2-14.7%) higher, and HR was on average 5.3 beats per minute (95% CI 1.7-9.0 bpm) higher during increased lateral trunk lean walking. CONCLUSION: Increased lateral trunk lean walking on a treadmill resulted in significantly higher levels of steady-state energy expenditure, HR, and perceived exertion, but no difference in knee pain. While increased lateral trunk lean has been shown to reduce biomechanical measures of joint loading relevant to OA progression, it should be prescribed with caution given the potential increase in energy expenditure experienced when it is employed.


Assuntos
Metabolismo Energético/fisiologia , Marcha/fisiologia , Osteoartrite do Joelho/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos/fisiologia , Índice de Massa Corporal , Teste de Esforço , Feminino , Frequência Cardíaca/fisiologia , Humanos , Articulação do Joelho/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/complicações , Consumo de Oxigênio/fisiologia , Dor/etiologia , Índice de Gravidade de Doença , Caminhada/fisiologia , Suporte de Carga/fisiologia
4.
Heliyon ; 10(5): e26769, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439890

RESUMO

Background: Although it is widely recognized that more attention needs to be paid to children's fluid intake, there is little information on how to improve it. Peer education has been suggested as an effective approach to changing health behaviors among school children. As a new approach, our study piloted a peer education program to improve children's fluid intake in primary schools. Methods: University students were prepared for their role as peer educators in an elective university course, including the concept of peer education and different pedagogical methods. The peer educators evaluated the training process by completing a questionnaire. The intervention took place during a School Health Day led by the peer educators. An anonymous survey with a questionnaire on knowledge of fluid intake was administered two weeks before, at the end of, and 15 weeks after the intervention. Changes in hydration knowledge were tested using repeated measures ANOVA. Results: The pilot program showed increased knowledge about fluid consumption (p < 0.001) in lower and upper primary school children (N = 326) at the end of the School Health Day compared to pre-intervention measures. A positive change was observed after 15 weeks only in upper primary students. Feedback from peer educators was useful for fine-tuning the program. Conclusions: This innovative program induced positive changes in knowledge about fluid intake in primary school children. The persistence of the changes differed between lower and upper primary school children. Based on the results, the intervention should be replicated to adapt the program to the needs of lower primary school children. Because the training of peer educators and the peer education program appeared to be successful, this program is worthy of international replication. This approach may also be suggested for other behavior change issues.

5.
Physiol Int ; 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33769958

RESUMO

OBJECTIVES: Conditions that have similar initial presentations as sepsis may make early recognition of sepsis in an emergency room (ER) difficult. We investigated whether selected physiologic and metabolic parameters can be reliably used in the emergency department to differentiate sepsis from other disease states that mimic it, such as dehydration and stroke. METHODS: Loess regression on retrospective follow-up chart data of patients with sepsis-like symptoms (N = 664) aged 18+ in a large ER in Hungary was used to visualize/identify cutoff points for sepsis risk. A multivariate logistic regression model based on standard triage data was constructed with its corresponding receiver operating characteristic (ROC) curve and compared with another model constructed based on current sepsis guidelines. RESULTS: Age, bicarbonate, HR, lactate, pH, and body temperature had U, V, W, or reverse U-shaped associations with identifiable inflexion points, but the cutoff values we identified were slightly different from guideline cutoff values. In contrast to the guidelines, no inflexion points could be observed for the association of sepsis with SBP, DPB, MAP, and RR and therefore were treated as continuous variables. Compared to the guidelines-based model, the triage data-driven final model contained additional variables (age, pH, bicarbonate) and did not include lactate. The data-driven model identified about 85% of sepsis cases correctly, while the guidelines-based model identified only about 70% of sepsis cases correctly. CONCLUSION: Our findings contribute to the growing body of evidence for the necessity of finding improved tools to identify sepsis at early time points, such as in the ER.

6.
Science ; 263(5145): 367-9, 1994 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-17769802

RESUMO

Photorefractive materials can form "instant" holograms without time-consuming development steps. Their potential applications include image processing, optical data storage, and correction of image distortion, but the cost of crystal growth and preparation has been a primary impediment to commercial application. Polymers, on the other hand, are low in cost and readily fabricated in a variety of forms. Photorefractive polymers were constructed with performance that matched or exceeded the performance of available photorefractive crystals. The largest observed two-beam energy coupling gain coefficient for the polymers was 56 per centimeter.

7.
Commun Agric Appl Biol Sci ; 74(2): 309-12, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20222585

RESUMO

In the course of our work we often faced to the problem that WCR lays its eggs unevenly (Berger, 2008) so it is impossible to find soils under field circumstances which contains eggs in homogenous distribution and in large numbers. Owing to the inhomogeneous distribution and low number of eggs it is quite difficult to study the effectiveness of soil disinfectant and seed-dressing insecticides on larvae of WCR in pot experiments. Therefore, the aim of our studies was to gain soil samples with known quantity and distribution of eggs. According to our prevailing idea, numerous adults are placed into a relatively small place under ideal environmental conditions and a small quantity of soil is provided for them to lay eggs.


Assuntos
Besouros/patogenicidade , Plantas/parasitologia , Solo/parasitologia , Animais , Besouros/crescimento & desenvolvimento , Meio Ambiente , Feminino , Hungria , Oviposição , Controle de Pragas/métodos
8.
Acta Biol Hung ; 59(2): 147-61, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18637555

RESUMO

We have investigated the expression of Doublecortin (Dcx) protein in the developing cerebellum of mouse from postnatal 2nd day to postnatal 22nd day and in young adults by immunohistochemistry. Strong expression of Dcx was present in the inner zone of the external granule cell layer, and remained strong while postmitotic granule cell precursors were present in this transitory layer. Descending granule cell precursors exhibited Dcx immunostaining not only while migrating but for a short time also after their settlement. Dcx-immunostained cells appeared in deep cerebellocortical territories and in the cerebellar white matter during the first postnatal week. These bipolar cells were arranged in the sagittal plane and built up transitory migratory streams during the second postnatal week and their number gradually decreased during the third postnatal week. Upward migration of bipolar cells was observed while leaving the migratory streams, penetrating the internal granule cell layer and the molecular layer. These cells were considered as precursors of late migrating molecular layer interneurons. However, a proportion of Dcx-immunostained cells underwent a bipolar-to-multipolar dendritic remodellation and - on the basis of strong morphological similarities - was taken for "multipotent progenitor cells", described recently in the neocortex of adult rat.


Assuntos
Envelhecimento/metabolismo , Córtex Cerebelar/crescimento & desenvolvimento , Córtex Cerebelar/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/fisiologia , Neuropeptídeos/metabolismo , Animais , Animais Recém-Nascidos , Movimento Celular , Proteínas do Domínio Duplacortina , Proteína Duplacortina , Camundongos
9.
Chem Commun (Camb) ; 54(38): 4838-4841, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29696267

RESUMO

γ,δ-Unsaturated amides in which the alkene moiety bears an aryl or heteroaryl substituent undergo regioselective rhodium-catalyzed δ-borylation by pinacolborane to afford chiral secondary benzylic boronic esters. The results contrast the γ-borylation of γ,δ-unsaturated amides in which the disubstituted alkene moiety bears only alkyl substituents; the reversal in regiochemistry is coupled with a reversal in the sense of π-facial selectivity.

10.
Biochim Biophys Acta ; 880(1): 1-9, 1986 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-3942777

RESUMO

Combined NMR and the vacuum dehydration method were used to study the state of water in rat muscle. Comparative studies were carried out on muscles of young and old mature white rats. The spin-lattice relaxation time was measured as a function of water content. The single-exponential behaviour of the relaxation process indicates a normal fast-exchange process between the different fractions. The more elaborate analysis demonstrates the failure of the original fast-exchange model. It is proved that structural changes take place in the macromolecule/ion/bound water system of the muscle even at the beginning of dehydration. All the muscle water seems to be necessary to maintain the normal natural state of the muscle's molecular structure.


Assuntos
Água Corporal , Músculos , Fatores Etários , Animais , Feminino , Espectroscopia de Ressonância Magnética , Ratos
11.
Int J Dev Neurosci ; 23(1): 27-35, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15730884

RESUMO

We have studied the postnatal quantitative changes of cortical Purkinje neurons in the cerebellum of the cat at the following postnatal groups of age: P0, P42, P72 and adults. An unbiased counting method, the optical fractionator was used for the estimation of Purkinje cell numbers. A significant increase of Purkinje cell number was found between P0 (1.097 x 10(6)) and P42/P72 (1.805 x 10(6) and 1.895 x 10(6)) declining to 1.429 x 10(6) in the adult, still 30% higher than in the newborn. It was also observed that during the first few postnatal weeks large "gaps" were present in the Purkinje monolayer as revealed by Nissl staining and metabotropic glutamate receptor 1alpha immunocytochemistry. These Purkinje cell gaps were observed most frequently in well-definable areas, especially in the intermediate zone of the neocerebellum. Simultaneously with the numerical increase of Purkinje neurons between the P0 and P72 age groups, these gaps disappeared after the third postnatal week resulting in the completion of the Purkinje monolayer in the whole cerebellum.


Assuntos
Cerebelo/crescimento & desenvolvimento , Células de Purkinje/fisiologia , Fatores Etários , Envelhecimento/fisiologia , Animais , Animais Recém-Nascidos , Gatos , Contagem de Células/métodos , Cerebelo/citologia , Imuno-Histoquímica/métodos , Receptores de Glutamato Metabotrópico/metabolismo , Coloração e Rotulagem/métodos
12.
Int J Dev Neurosci ; 23(8): 723-9, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16289944

RESUMO

We have studied the temporal and spatial characteristics of the development of unipolar brush cells (UBCs) in the human cerebellar vermis. Consistently with previous studies in rodents and cat, we have found that unipolar brush cells appear at a relatively late phase of cerebellar development and their development continues up to and beyond the first postnatal year. A series of 23 normal human brains, including 5 adult and 18 fetal or infant brains (between the 24th gestational week and the 11th postnatal month) were used. In order to visualize unipolar brush cells, calretinin-immunocytochemistry was performed on formaldehyde-fixed, paraffin-embedded blocks of the cerebellar vermis. Our results show that calretinin-immunoreactive unipolar brush cells are not yet present in the cerebellar vermis at the 28th gestational week. At birth, they are present in a relatively small number, mostly in the vestibular lobules. At the 3rd, 5th, 8.5th and 11th postnatal months the number of calretinin-immunoreactive unipolar brush cells gradually increase, first appearing in the vestibular lobules, followed by the invasion of the later developing vermal lobules, spreading in a rostro-caudal and proximo-distal direction. Although at the 11th postnatal month unipolar brush cells exhibited adult-like morphological and distributional features, their number appeared to be lower than in the adult cerebellum. The late maturation of unipolar brush cells implies that the cytoarchitectonical development of the human cerebellum is not completed by the end of the first postnatal year.


Assuntos
Cerebelo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Neurônios/metabolismo , Proteína G de Ligação ao Cálcio S100/metabolismo , Idoso , Idoso de 80 Anos ou mais , Calbindina 2 , Contagem de Células/métodos , Cerebelo/citologia , Cerebelo/crescimento & desenvolvimento , Cerebelo/metabolismo , Feminino , Feto , Humanos , Imuno-Histoquímica/métodos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Neurônios/fisiologia
13.
Anat Embryol (Berl) ; 209(6): 471-84, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15887047

RESUMO

The postnatal development of the ganglionic (Purkinje) layer was studied in the mouse cerebellum from P0 to young adulthood with special emphasis to vermal lobules VI-VII (oculomotor vermis) in the mouse. In order to visualize Purkinje cells (PCs), toluidine blue staining of resin-embedded semithin sections and calbindin immunohistochemistry were utilized. The number of PCs in the whole cerebellum was 199,080+/-2966 at postnatal day eight (P8), 222,000+/-2979 at P20 and nearly the same, 225,800+/-7549 in young adults; i.e., there was an approximately 13.4% increase of PCs between P8 and adults. The number of PC somata aligned into a rostrocaudal stripe along the developing ganglionic layer increased by about 24% in vermal cerebellar lobule III but much more markedly (i.e., by 49%) in VI+VII between P6 and young adulthood. Between P6 and P16, the increase of the number of PCs in the ganglionic layer of lobules VI and VII resulted in the (delayed) completion of PC layer, caused by the (late) alignment of rostrocaudally dispersed PCs, although late postnatal migration of a smaller population of these cells cannot be excluded either. It is concluded that the oculomotor vermis belongs to the latest developing cerebellar cortical structures, which could be the reason for its frequent involvement in developmentally related disturbances and disorders.


Assuntos
Córtex Cerebelar , Células de Purkinje/citologia , Animais , Animais Recém-Nascidos , Biomarcadores/metabolismo , Calbindinas , Proteínas de Ligação ao Cálcio/metabolismo , Contagem de Células , Diferenciação Celular , Córtex Cerebelar/citologia , Córtex Cerebelar/crescimento & desenvolvimento , Córtex Cerebelar/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/metabolismo , Células de Purkinje/metabolismo , Proteína G de Ligação ao Cálcio S100
14.
Commun Agric Appl Biol Sci ; 70(4): 693-6, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16628905

RESUMO

Main method to control the American Corn Rootworm is crop rotation (Camprag et. al., 1994) but we don't know how to determine the possible number of larvae under fall so we cannot use autumn cereals to change the row of cultivated plants. The pest spends almost 10 months in soil in egg and larval state (Chiang, 1973). There are two methods for scouting Diabrotica eggs and larval instars from soil over the winter. One of the two most important methods is holding soil samples on fixed temperature (Fromm et al., 1999). This method takes more than one and a half month but its result is highly reliable. The conventional egg-washing technique takes fewer days to count the number of Diabrotica eggs in soil but it has lower effectiveness than the other one because the eggs in a sample cannot be counted correctly. Our results show that the effectiveness of egg washing with high concentrated salty water (NaCl) is high and the method is quick enough to help planning the crop rotation even under the autumn period (Takács et al., 2004).


Assuntos
Besouros/crescimento & desenvolvimento , Solo/parasitologia , Agricultura/métodos , Animais , Feminino , Larva/crescimento & desenvolvimento , Masculino , Densidade Demográfica , Temperatura , Zea mays/parasitologia
15.
J Comp Neurol ; 302(4): 739-48, 1990 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-1982005

RESUMO

GABA and glutamate immunogold staining demonstrated that nerve cells of the thalamic ventrobasal complex (VB) of mice were positive exclusively for glutamate. None of the neuronal perikarya reacted the GABA antibody. By using alternate thin sections of the normal VB, it was also shown that large "specific" somatosensory and small corticothalamic terminals, both of which contained spherical synaptic vesicles, exhibited only glutamate-like immunoreactivity. A third axonal type, containing flat-ovoid synaptic vesicles, stained only for GABA. Seventy-five days after coagulation of the vibrissal follicles in newborn mice, a characteristic multiplication of GABA positive axon terminals was observed. In addition, it was demonstrated that, similarly to modified cortical endings (Hámori et al., J. Comp. Neurol. 254:166-183, '86), many GABA positive terminals appeared as specific afferent endings, replacing the missing "specific" vibrissal afferents. This finding shows a remarkable plasticity of inhibitory GABA axons during developmental synaptogenesis and provides further evidence that the size, location, and the type of attachment of presynaptic terminals are dependent on their postsynaptic target.


Assuntos
Glutamatos/análise , Plasticidade Neuronal , Tálamo/fisiologia , Vibrissas/fisiologia , Ácido gama-Aminobutírico/análise , Vias Aferentes/crescimento & desenvolvimento , Vias Aferentes/fisiologia , Animais , Axônios/química , Ácido Glutâmico , Imuno-Histoquímica , Camundongos , Microscopia Eletrônica , Terminações Nervosas/química , Terminações Nervosas/ultraestrutura , Tálamo/química , Tálamo/ultraestrutura
16.
J Comp Neurol ; 254(2): 166-83, 1986 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-3794005

RESUMO

Morphological modifications of two subcortical vibrissal relays were analyzed, following destruction of vibrissal follicles in newborn mice. The volume of the nucleus interpolaris (NI) of the trigeminal nuclear complex in the brainstem decreased by 33%, while the number of its neuronal perikarya decreased only moderately. Vibrissal deafferentation caused no shrinkage of the ventrobasal complex (VB). In the damaged medial vibrissal part of VB (VBm), however, neuronal density was higher than normal, indicating the prevention or retardation of physiologically programmed cell death in the afferentation deprived thalamic somatosensory relay station. It is suggested that the difference in neuron density produced by deafferentation is related to the states of maturation at birth of the two subcortical vibrissal relays. Following vibrissal deafferentation the basic organization of the synaptic neuropil appeared to be similar to the control. Quantitative electron microscopic (EM) analysis revealed, however, an increased number of axon terminals with ovoid synaptic vesicles in both deafferented relay stations. The increased density of gamma-aminobutyric acid (GABA)-immunostained boutons observed in the VBm following vibrissal deprivation suggested a compensatory increase most probably of the inhibitory axon endings. Quantitative EM analysis also provided evidence that many or most of the specific afferent terminals in the damaged VBm were not identical with but were substitutes for the original "vibrissal" specific afferents. Forty percent of all "specific" afferents were shown to be modified corticothalamic terminals. The modification and the resemblence of some cortical endings to specific afferents demonstrated the morphogenetic plasticity of synaptogenesis in these terminals during development as well as the importance and inductive potential of the postsynaptic target in the differentiation of presynaptic axon terminals.


Assuntos
Animais Recém-Nascidos/fisiologia , Neurônios Aferentes/ultraestrutura , Tálamo/ultraestrutura , Núcleos do Trigêmeo/ultraestrutura , Vibrissas/inervação , Animais , Denervação , Camundongos , Camundongos Endogâmicos , Terminações Nervosas/ultraestrutura , Plasticidade Neuronal , Vesículas Sinápticas/ultraestrutura
17.
J Histochem Cytochem ; 38(12): 1767-77, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1979341

RESUMO

Selective labeling of mossy fiber terminals and parallel fibers was obtained in rat cerebellar cortex by a glutamate antibody produced and characterized by Hepler et al. The high-resolution electron microscopic immunogold demonstration of this amino acid offered the possibility of determining the size and shape of synaptic vesicles in glutamate-positive mossy endings. Mossy terminals that stained with the glutamate antibody formed two distinct populations, one with spherical synaptic vesicles with an average diameter of 34.0 nm (more than 90% of all mossy fiber endings) and one with pleomorphic and smaller synaptic vesicles which had an average diameter of 28.5 nm. We present experimental evidence that the mossy terminals with large round vesicles are of extracerebellar origin, whereas those with small pleomorphic synaptic vesicles are endings of nucleocortical fibers. The presence of two distinct classes of gamma-aminobutyric acid (GABA)-containing axon terminals within cerebellar glomeruli has also been demonstrated; those originating from the cerebellar nuclei contain large (36.2 nm) synaptic vesicles, whereas the majority of GABA-stained axon terminals that are of local (cortical) origin contain small (29.1 nm) synaptic vesicles. It therefore appears that, at least in the case of glutamate and GABA, morphological characterization of the axon terminals based on the size and shape of synaptic vesicles is not a reliable indicator of their functional nature (i.e., whether they are excitatory or inhibitory); convincing evidence for the identity of the transmitter can be obtained only by electron microscopic immunostaining procedures. Our results also suggest the existence of both inhibitory and excitatory feedback from cerebellar nuclei to cerebellar cortex.


Assuntos
Córtex Cerebelar/química , Glutamatos/análise , Imuno-Histoquímica , Microscopia Imunoeletrônica , Vesículas Sinápticas/ultraestrutura , Ácido gama-Aminobutírico/análise , Animais , Axônios/química , Axônios/ultraestrutura , Córtex Cerebelar/ultraestrutura , Denervação , Ácido Glutâmico , Masculino , Terminações Nervosas/química , Terminações Nervosas/ultraestrutura , Ratos
18.
Br J Pharmacol ; 133(5): 625-34, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11429385

RESUMO

The electrophysiological effects of dronedarone, a new nonionidated analogue of amiodarone were studied after chronic and acute administration in dog Purkinje fibres, papillary muscle and isolated ventricular myocytes, and compared with those of amiodarone by applying conventional microelectrode and patch-clamp techniques. Chronic treatment with dronedarone (2x25 mg(-1) kg(-1) day p.o. for 4 weeks), unlike chronic administration of amiodarone (50 mg(-1) kg(-1) day p.o. for 4 weeks), did not lengthen significantly the QTc interval of the electrocardiogram or the action potential duration (APD) in papillary muscle. After chronic oral treatment with dronedarone a small, but significant use-dependent V(max) block was noticed, while after chronic amiodarone administration a strong use-dependent V(max) depression was observed. Acute superfusion of dronedarone (10 microM), similar to that of amiodarone (10 microM), moderately lengthened APD in papillary muscle (at 1 Hz from 239.6+/-5.3 to 248.6+/-5.3 ms, n=13, P<0.05), but shortened it in Purkinje fibres (at 1 Hz from 309.6+/-11.8 to 287.1+/-10.8 ms, n=7, P<0.05). Both dronedarone (10 microM) and amiodarone (10 microM) superfusion reduced the incidence of early and delayed afterdepolarizations evoked by 1 microM dofetilide and 0.2 microM strophantidine in Purkinje fibres. In patch-clamp experiments 10 microM dronedarone markedly reduced the L-type calcium current (76.5+/-0.7 %, n=6, P<0.05) and the rapid component of the delayed rectifier potassium current (97+/-1.2 %, n=5, P<0.05) in ventricular myocytes. It is concluded that after acute administration dronedarone exhibits effects on cardiac electrical activity similar to those of amiodarone, but it lacks the 'amiodarone like' chronic electrophysiological characteristics.


Assuntos
Amiodarona/análogos & derivados , Amiodarona/farmacologia , Ventrículos do Coração/efeitos dos fármacos , Vasodilatadores/farmacologia , Potenciais de Ação/efeitos dos fármacos , Amiodarona/sangue , Amiodarona/química , Animais , Cães , Dronedarona , Estimulação Elétrica , Eletrocardiografia , Eletrofisiologia , Feminino , Ventrículos do Coração/citologia , Técnicas In Vitro , Masculino , Músculos Papilares/efeitos dos fármacos , Músculos Papilares/fisiologia , Ramos Subendocárdicos/efeitos dos fármacos , Ramos Subendocárdicos/fisiologia , Função Ventricular
19.
J Clin Pathol ; 38(6): 653-8, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2989341

RESUMO

A number of conditions are associated with abnormalities of trace metal handling by the liver. We report the application of the Oxford scanning proton microprobe to the analysis of hepatic copper in one such condition, primary biliary cirrhosis. The scanning proton microprobe analyses conventional tissue sections (5-10 micron thickness) and produces simultaneous elemental distribution maps of biologically relevant elements with a spatial resolution of 1 micron and a detection limit better than 1 ppm. We have confirmed the localisation of excess copper to periportal areas and suggest that such accumulation is confined to a proportion of periportal hepatocytes. We have also shown a close spatial correlation between regions of copper accumulation and areas of high sulphur concentration. The copper to sulphur ratio in these areas is consistent with their identity as aggregates of copper loaded metallothionein, and the scanning proton microprobe was further able to show that the aggregates contain less than 30 ppm zinc.


Assuntos
Cobre/metabolismo , Cirrose Hepática Biliar/metabolismo , Fígado/metabolismo , Computadores , Humanos , Prótons , Espectrometria por Raios X , Enxofre/metabolismo , Distribuição Tecidual , Oligoelementos/metabolismo
20.
Neuroreport ; 11(11): 2597-600, 2000 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-10943729

RESUMO

The neuroprotective/neuronal rescue effects of selegiline are not exactly understood, and show great variability in clinical trials. In this study, the dose-dependence of neuronal rescue potency of selegiline and its analogue para-fluoro-selegiline (PFS) was investigated in gerbils. The compounds were tested in a transient global cerebral ischemia model. Selegiline expressed a bell-shaped, dose-response curve with high intrinsic activity (with greatest effect at 0.001 mg/kg), as opposed to PFS which shows a saturation profile. These findings indicate possible therapeutic differences between PFS and selegiline in the treatment of neurodegenerative disorders. Inhibition of progression of the disease (neuroprotective effect) and improvements of symptoms (MAO-B inhibition) may occur at the same dose level using PFS, while these doses are separated in case of selegiline.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Compostos de Flúor/farmacologia , Degeneração Neural/tratamento farmacológico , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Selegilina/farmacologia , Animais , Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Sobrevivência Celular/fisiologia , Relação Dose-Resposta a Droga , Gerbillinae , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Hipocampo/fisiopatologia , Masculino , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/patologia , Doenças Neurodegenerativas/fisiopatologia , Neurônios/metabolismo , Neurônios/patologia , Células Piramidais/efeitos dos fármacos , Células Piramidais/metabolismo , Células Piramidais/patologia , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Selegilina/análogos & derivados
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