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1.
Med Oral Patol Oral Cir Bucal ; 26(3): e393-e403, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33247564

RESUMO

BACKGROUND: Salivary gland cancers (SGC) represent an uncommon group of heterogeneous tumors. We performed a retrospective survey of SGC diagnosed in a reference center for treatment of malignant tumors from the south of Brazil aiming to determine the prognostic value of demographic, clinic and pathologic features. MATERIAL AND METHODS: Cases diagnosed as SGC between 2006 and 2016 were retrospectively collected. Medical records were examined to extract demographic, clinic, pathologic and follow-up information. RESULTS: One-hundred and seven cases of SGC were identified. The most common SGC were mucoepidermoid carcinoma (MEC) (n = 39) followed by adenoid cystic carcinoma (AdCC) (n = 29). Among AdCCs, 55.2% of cases were classified as cribriform, 27.6% as tubular and 17.2% as solid. The tubular subtype had the highest percentage of cases with perineural invasion (p=0.01). Among MEC, 61.5% of cases were classified as low grade, 15.4% as intermediate grade and 19.9% as high grade. Low grade MEC had the lowest percentage of cases with perineural invasion (p=0.04). The 5-year survival for loco-regional control, disease-free survival (DFS) and disease-specific survival were 75%, 70% and 84%, respectively. The following features were associated with poor DFS: advanced age (p=0.03), rural residency (p=0.01), being a smoker or former smoker (p=0.01), pain (p=0.03), nodal metastasis (p<0.001), need for chemotherapy (p=0.02), neck dissection (p=0.04), perineural invasion (p=0.01), and being diagnosed with AdCC compared to MEC (p=0.02). CONCLUSIONS: The clinco-demographic and pathologic features identified as prognostic factors reveal the profile of patients at increased risk of recurrence and who would benefit from closer follow-up.


Assuntos
Recidiva Local de Neoplasia , Neoplasias das Glândulas Salivares , Brasil/epidemiologia , Humanos , Prognóstico , Estudos Retrospectivos , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias das Glândulas Salivares/epidemiologia , Neoplasias das Glândulas Salivares/terapia
2.
Eur J Appl Physiol ; 120(7): 1651-1656, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32447452

RESUMO

PURPOSE: This study sought to investigate the electromyographic activity of the vastus lateralis (VL) muscle during concentric-eccentric exercise using a new concept leg press machine enabling a preset overloading in the eccentric phase. METHODS: Ten young males familiar with resistive exercise were recruited for this study. Tests were performed on a Leg-press Biostrength® (Technogym S.p.A., Italy). The load was set to 70% and 80% of one-repetition maximum (1-RM). The participants performed 2 sets of 6 repetitions at each relative load with (ECC +) and without (ISOW) an eccentric overload equivalent to 150% of the concentric load. A metronome was employed to maintain the selected cadence. Sets were separated by a 5-min rest. Surface electromyography (EMG) of VL was recorded and integrated (iEMG). RESULTS: Results showed a higher iEMG in ECC + with respect to ISOW at both intensities (+ 29% for 70% 1-RM, p < 0.01 and + 31% for 80% 1-RM, p < 0.001). No statistically significant differences were detected between concentric and eccentric phase in both ECC + conditions. CONCLUSIONS: Training with a 150% eccentric overload provides a ~ 30% greater motor unit recruitment of the VL muscle in leg press exercise. Moreover, the results show that the eccentric overloading provided by the Biostrength® machine enables training at the same level of neural activation of the concentric phase. Hence, the derecruitment of motor units, normally observed during the eccentric phase when using conventional training machines, was overcome using the Biostrength® machine; this observation seems particularly important for maximizing neuromuscular responses to strength training.


Assuntos
Exercício Físico/fisiologia , Perna (Membro)/fisiologia , Contração Muscular/fisiologia , Força Muscular/fisiologia , Adulto , Feminino , Humanos , Masculino , Músculo Esquelético/fisiologia , Treinamento de Força/métodos , Adulto Jovem
3.
Tissue Cell ; 42(5): 307-13, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20817239

RESUMO

Nitric oxide (NO) is a gas produced through the action of nitric oxide synthase that acts as a neurotransmitter in the central nervous system (CNS) of adult gastropod mollusks. There are no known reports of the presence of NOS-containing neurons and glial cells in young and adult Megalobulimus abbreviatus. Therefore, NADPH-d histochemistry was employed to map the nitrergic distribution in the CNS of young and adult snails in an attempt to identify any transient enzymatic activity in the developing CNS. Reaction was observed in neurons and fibers in all CNS ganglia of both age groups, but in the pedal and cerebral ganglia, positive neurons were more intense than in other ganglia, forming clusters symmetrically located in both paired ganglia. However, neuronal NADPH-d activity in the mesocerebrum and pleural ganglia decreased from young to adult animals. In both age groups, positive glial cells were located beneath the ganglionic capsule, forming a network and surrounding the neuronal somata. The trophospongium of large and giant neurons was only visualized in young animals. Our results indicate the presence of a nitrergic signaling system in young and adult M. abbreviatus, and the probable involvement of glial cells in NO production.


Assuntos
Sistema Nervoso Central/enzimologia , Gânglios dos Invertebrados/enzimologia , NADPH Desidrogenase/metabolismo , Óxido Nítrico Sintase/metabolismo , Envelhecimento , Animais , Sistema Nervoso Central/crescimento & desenvolvimento , Caramujos
4.
Braz. j. med. biol. res ; 43(1): 85-95, Jan. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-535638

RESUMO

The objective of the present study was to determine whether lesion of the subthalamic nucleus (STN) promoted by N-methyl-D-aspartate (NMDA) would rescue nigrostriatal dopaminergic neurons after unilateral 6-hydroxydopamine (6-OHDA) injection into the medial forebrain bundle (MFB). Initially, 16 mg 6-OHDA (6-OHDA group) or vehicle (artificial cerebrospinal fluid - aCSF; Sham group) was infused into the right MFB of adult male Wistar rats. Fifteen days after surgery, the 6-OHDA and SHAM groups were randomly subdivided and received ipsilateral injection of either 60 mM NMDA or aCSF in the right STN. Additionally, a control group was not submitted to stereotaxic surgery. Five groups of rats were studied: 6-OHDA/NMDA, 6-OHDA/Sham, Sham/NMDA, Sham/Sham, and Control. Fourteen days after injection of 6-OHDA, rats were submitted to the rotational test induced by apomorphine (0.1 mg/kg, ip) and to the open-field test. The same tests were performed again 14 days after NMDA-induced lesion of the STN. The STN lesion reduced the contralateral turns induced by apomorphine and blocked the progression of motor impairment in the open-field test in 6-OHDA-treated rats. However, lesion of the STN did not prevent the reduction of striatal concentrations of dopamine and metabolites or the number of nigrostriatal dopaminergic neurons after 6-OHDA lesion. Therefore, STN lesion is able to reverse motor deficits after severe 6-OHDA-induced lesion of the nigrostriatal pathway, but does not protect or rescue dopaminergic neurons in the substantia nigra pars compacta.


Assuntos
Animais , Masculino , Ratos , Dopamina/fisiologia , Atividade Motora/efeitos dos fármacos , Neurônios/patologia , Doença de Parkinson Secundária/patologia , Substância Negra/citologia , Núcleo Subtalâmico/lesões , Imuno-Histoquímica , Atividade Motora/fisiologia , N-Metilaspartato , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Veículos Farmacêuticos , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/fisiopatologia , Distribuição Aleatória , Ratos Wistar , Substância Negra/fisiopatologia , Núcleo Subtalâmico/efeitos dos fármacos , Núcleo Subtalâmico/patologia , Núcleo Subtalâmico/cirurgia , /metabolismo
5.
Braz J Med Biol Res ; 43(1): 85-95, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19967265

RESUMO

The objective of the present study was to determine whether lesion of the subthalamic nucleus (STN) promoted by N-methyl-D-aspartate (NMDA) would rescue nigrostriatal dopaminergic neurons after unilateral 6-hydroxydopamine (6-OHDA) injection into the medial forebrain bundle (MFB). Initially, 16 mg 6-OHDA (6-OHDA group) or vehicle (artificial cerebrospinal fluid - aCSF; Sham group) was infused into the right MFB of adult male Wistar rats. Fifteen days after surgery, the 6-OHDA and SHAM groups were randomly subdivided and received ipsilateral injection of either 60 mM NMDA or aCSF in the right STN. Additionally, a control group was not submitted to stereotaxic surgery. Five groups of rats were studied: 6-OHDA/NMDA, 6-OHDA/Sham, Sham/NMDA, Sham/Sham, and Control. Fourteen days after injection of 6-OHDA, rats were submitted to the rotational test induced by apomorphine (0.1 mg/kg, ip) and to the open-field test. The same tests were performed again 14 days after NMDA-induced lesion of the STN. The STN lesion reduced the contralateral turns induced by apomorphine and blocked the progression of motor impairment in the open-field test in 6-OHDA-treated rats. However, lesion of the STN did not prevent the reduction of striatal concentrations of dopamine and metabolites or the number of nigrostriatal dopaminergic neurons after 6-OHDA lesion. Therefore, STN lesion is able to reverse motor deficits after severe 6-OHDA-induced lesion of the nigrostriatal pathway, but does not protect or rescue dopaminergic neurons in the substantia nigra pars compacta.


Assuntos
Dopamina/fisiologia , Atividade Motora/efeitos dos fármacos , Neurônios/patologia , Doença de Parkinson Secundária/patologia , Substância Negra/citologia , Núcleo Subtalâmico/lesões , Animais , Imuno-Histoquímica , Masculino , Atividade Motora/fisiologia , N-Metilaspartato , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/fisiopatologia , Veículos Farmacêuticos , Distribuição Aleatória , Ratos , Ratos Wistar , Substância Negra/fisiopatologia , Núcleo Subtalâmico/efeitos dos fármacos , Núcleo Subtalâmico/patologia , Núcleo Subtalâmico/cirurgia , Tirosina 3-Mono-Oxigenase/metabolismo
6.
Braz J Med Biol Res ; 38(1): 73-80, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15665992

RESUMO

We describe the behavior of the snail Megalobulimus abbreviatus upon receiving thermal stimuli and the effects of pretreatment with morphine and naloxone on behavior after a thermal stimulus, in order to establish a useful model for nociceptive experiments. Snails submitted to non-functional (22 degrees C) and non-thermal hot-plate stress (30 degrees C) only displayed exploratory behavior. However, the animals submitted to a thermal stimulus (50 degrees C) displayed biphasic avoidance behavior. Latency was measured from the time the animal was placed on the hot plate to the time when the animal lifted the head-foot complex 1 cm from the substrate, indicating aversive thermal behavior. Other animals were pretreated with morphine (5, 10, 20 mg/kg) or naloxone (2.5, 5.0, 7.5 mg/kg) 15 min prior to receiving a thermal stimulus (50 degrees C; N = 9 in each group). The results (means +/- SD) showed an extremely significant difference in response latency between the group treated with 20 mg/kg morphine (63.18 +/- 14.47 s) and the other experimental groups (P < 0.001). With 2.5 mg/kg (16.26 +/- 3.19 s), 5.0 mg/kg (11.53 +/- 1.64 s) and 7.5 mg/kg naloxone (7.38 +/- 1.6 s), there was a significant, not dose-dependent decrease in latency compared to the control (33.44 +/- 8.53 s) and saline groups (29.1 +/- 9.91 s). No statistically significant difference was found between the naloxone-treated groups. With naloxone plus morphine, there was a significant decrease in latency when compared to all other groups (minimum 64% in the saline group and maximum 83.2% decrease in the morphine group). These results provide evidence of the involvement of endogenous opioid peptides in the control of thermal withdrawal behavior in this snail, and reveal a stereotyped and reproducible avoidance behavior for this snail species, which could be studied in other pharmacological and neurophysiological studies.


Assuntos
Analgésicos Opioides/farmacologia , Comportamento Animal/efeitos dos fármacos , Temperatura Alta , Morfina/farmacologia , Naloxona/farmacologia , Caramujos/efeitos dos fármacos , Animais , Regulação da Temperatura Corporal/efeitos dos fármacos , Naloxona/antagonistas & inibidores , Tempo de Reação/efeitos dos fármacos , Termorreceptores/efeitos dos fármacos
7.
Braz. j. med. biol. res ; 38(1): 73-80, Jan. 2005. ilus, graf
Artigo em Inglês | LILACS | ID: lil-405539

RESUMO

We describe the behavior of the snail Megalobulimus abbreviatus upon receiving thermal stimuli and the effects of pretreatment with morphine and naloxone on behavior after a thermal stimulus, in order to establish a useful model for nociceptive experiments. Snails submitted to non-functional (22°C) and non-thermal hot-plate stress (30°C) only displayed exploratory behavior. However, the animals submitted to a thermal stimulus (50°C) displayed biphasic avoidance behavior. Latency was measured from the time the animal was placed on the hot plate to the time when the animal lifted the head-foot complex 1 cm from the substrate, indicating aversive thermal behavior. Other animals were pretreated with morphine (5, 10, 20 mg/kg) or naloxone (2.5, 5.0, 7.5 mg/kg) 15 min prior to receiving a thermal stimulus (50°C; N = 9 in each group). The results (means ± SD) showed an extremely significant difference in response latency between the group treated with 20 mg/kg morphine (63.18 ± 14.47 s) and the other experimental groups (P < 0.001). With 2.5 mg/kg (16.26 ± 3.19 s), 5.0 mg/kg (11.53 ± 1.64 s) and 7.5 mg/kg naloxone (7.38 ± 1.6 s), there was a significant, not dose-dependent decrease in latency compared to the control (33.44 ± 8.53 s) and saline groups (29.1 ± 9.91 s). No statistically significant difference was found between the naloxone-treated groups. With naloxone plus morphine, there was a significant decrease in latency when compared to all other groups (minimum 64 percent in the saline group and maximum 83.2 percent decrease in the morphine group). These results provide evidence of the involvement of endogenous opioid peptides in the control of thermal withdrawal behavior in this snail, and reveal a stereotyped and reproducible avoidance behavior for this snail species, which could be studied in other pharmacological and neurophysiological studies.


Assuntos
Animais , Analgésicos Opioides/farmacologia , Comportamento Animal/efeitos dos fármacos , Temperatura Alta , Morfina/farmacologia , Naloxona/farmacologia , Caramujos/efeitos dos fármacos , Regulação da Temperatura Corporal/efeitos dos fármacos , Naloxona/antagonistas & inibidores , Tempo de Reação/efeitos dos fármacos , Termorreceptores/efeitos dos fármacos
8.
Ann Otolaryngol Chir Cervicofac ; 120(1): 3-13, 2003 Feb.
Artigo em Francês | MEDLINE | ID: mdl-12717312

RESUMO

OBJECTIVES: We analyzed retrospectively the files of 130 patients with unresectable cancer of the head and neck who were given concomitant radiotherapy-chemotherapy between January 1993 and February 2000. PATIENTS AND METHODS: The series included 41 patients with grade III cancer, 64 grade IVA, and 25 grade IVB. Treatment combined radiotherapy (70.2 Gy centered on the tumor with 50.4 Gy on the lymph nodes) and chemotherapy using three cycles of cisplatinium combined with 5-fluorouracil in continuous infusion for 120 hr. RESULTS: Local control was achieved in 51% of the patients at two years and 48% at five years. Overall survival was 45% at two years and 33% at five years, all grades included. CONCLUSION: Univariate analysis of prognostic factors points out the importance of the nutritional status before and during treatment.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Adulto , Idoso , Terapia Combinada , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Doses de Radiação , Estudos Retrospectivos
10.
Biochem J ; 326 ( Pt 3): 661-8, 1997 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9307014

RESUMO

Basic fibroblast growth factor (bFGF) and its specific receptors have diverse roles on a variety of cell types, such as the induction of vascular smooth-muscle cell proliferation which contributes to restenosis after coronary balloon angioplasty. bFGF is also known to interact with heparan sulphate proteoglycans present on the cell surface or in the extracellular matrix. In this study, the binding of 125I-bFGF to human aortic smooth-muscle cells was investigated. 125I-bFGF binding to these cells was reversible and saturable. Scatchard analysis revealed the presence of two distinct binding sites: a high-affinity receptor (Kd=38+/-7 pM; 1480+/-220 sites/cell) and a low-affinity non-saturable binding site (Kd=8. 0+/-2.0 nM). Pretreatment of the cells with heparinase resulted in a large reduction of 125I-bFGF binding to its low-affinity receptors, suggesting that they are heparin-like molecules. The specificity of the low- and high-affinity binding sites for bFGF was determined with acidic FGF, platelet-derived growth factor-BB and epidermal growth factor, which did not compete for 125I-bFGF binding. Expression of FGF receptor isoforms analysed by reverse transcriptase-PCR revealed the presence of only the type-1 receptor. Binding to low-affinity binding sites was antagonized by heparin, suramin, protamine sulphate and platelet factor 4. Unexpectedly, these molecules also reduced the binding of 125I-bFGF to its high-affinity sites. Consistent with these results, heparin, suramin, protamine sulphate and platelet factor 4 inhibited bFGF-induced proliferation of human aortic smooth-muscle cells. Heparin abrogated bFGF-induced release of tissue-type plasminogen activator by these cells. These observations suggest that the interaction of bFGF with human aortic smooth-muscle cells is different from that described for other cells such as endothelial cells, in which heparin acts as a potentiating factor of the mitogenic activity of bFGF.


Assuntos
Fibrinolíticos/farmacologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Heparina/farmacologia , Músculo Liso Vascular/metabolismo , Aorta/citologia , Aorta/metabolismo , Sítios de Ligação , Células Cultivadas , Humanos , Ligação Proteica/efeitos dos fármacos
11.
Rev Laryngol Otol Rhinol (Bord) ; 118(5): 311-4, 1997.
Artigo em Francês | MEDLINE | ID: mdl-9687650

RESUMO

Sensory illusions in hang-gliding and para-gliding. Hang-gliding and para-gliding are at the moment booming sports. Sensory illusions are physiological phenomena sharing the wrong perception of the pilote's real position in space. These phenomena are very familiar to aeroplane pilotes, they can also be noticed on certain conditions with hang-gliding pilotes. There are many and various sensory illusions, but only illusions of vestibular origin will be dealt with in this article. Vestibular physiology is reminded with the working principle of a semicircular canal. Physiology and laws of physics explain several sensory illusions, especially when the pilote loses his visual landmarks: flying through a cloud, coriolis effect. Also some specific stages of hang-gliding foster those phenomena: spiraling downwards, self-rotation, following an asymetric closing of the parachute, spin on oneself. Therefore a previous briefing for the pilotes seems necessary.


Assuntos
Ilusões/etiologia , Esportes , Humanos , Equilíbrio Postural/fisiologia , Vestíbulo do Labirinto/fisiologia
12.
Boll Soc Ital Biol Sper ; 65(3): 255-8, 1989 Mar.
Artigo em Italiano | MEDLINE | ID: mdl-2765248

RESUMO

L-Carnitine induces reversibility upon the lipid-graph of a rabbit with a surgically denerved heart after 90 days since it reduces the percentage of stearic acid but also increases thoroughly linoleic acid that notoriously has a plastic and regulatory effect on the heart.


Assuntos
Carnitina/fisiologia , Metabolismo dos Lipídeos , Miocárdio/metabolismo , Animais , Ácidos Araquidônicos/metabolismo , Denervação , Metabolismo Energético , Coração/inervação , Ácidos Linoleicos/metabolismo , Coelhos , Ácidos Esteáricos/metabolismo , Fatores de Tempo
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