RESUMO
Localized rectal adenocarcinoma is a heterogeneous disease and current treatment recommendations are based on a preoperative multidisciplinary evaluation. High-resolution magnetic resonance imaging and endoscopic ultrasound are complementary to do a locoregional accurate staging. Surgery remains the mainstay of treatment and preoperative therapies with chemoradiation (CRT) or short-course radiation (SCRT) must be considered in more locally advanced cases. Novel strategies with induction chemotherapy alone or preceding or after CRT (SCRT) and surgery are in development.
Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Guias de Prática Clínica como Assunto , Neoplasias Retais/diagnóstico , Neoplasias Retais/terapia , Humanos , Espanha , Resultado do TratamentoRESUMO
Intracellular recordings in in vitro slice preparations of rat brain were used to compare the actions of dopamine and dopamine receptor agonists on the subthreshold membrane properties of neostriatal neurons. A reproducible response for dopaminergic agonists was evoked after firing produced by current ramp injections that induced a subthreshold voltage displacement. Dopamine (10-100 microM) decreased both firing rate and membrane slope input resistance in virtually all cells tested. Input resistance change appeared as an increase in inward rectification. Approximate reversal potential was around -87 mV. The D1 receptor agonists SKF 38393 and Cl-APB (1-10 microM) mimicked both dopamine effects with a reversal potential around -89 mV. The effects were blocked by the presence of 5-10 mM caesium (Cs+) but not by 1 microM tetrodotoxin, suggesting that main D1 effects on input resistance are due to subthreshold Cs(+)-sensitive conductances. cAMP analogues mimicked the actions of D1 receptor agonists. The D2 agonist, quinpirole (1-10 microM), did not produce any input resistance change, nonetheless, it still produced a decrease in firing rate. This suggests that the main D2 effect on firing is due to actions on suprathreshold ion conductances. All effects were blocked by D1 and D2 antagonists, respectively. D1 or D2 effects were found in the majority of cells tested.
Assuntos
Agonistas de Dopamina/farmacologia , Dopamina/farmacologia , Neostriado/fisiologia , Receptores de Dopamina D1/efeitos dos fármacos , Receptores de Dopamina D2/efeitos dos fármacos , 2,3,4,5-Tetra-Hidro-7,8-Di-Hidroxi-1-Fenil-1H-3-Benzazepina/farmacologia , Potenciais de Ação/fisiologia , Animais , Benzazepinas/farmacologia , Césio/farmacologia , AMP Cíclico/análogos & derivados , AMP Cíclico/farmacologia , Estimulação Elétrica , Eletrofisiologia , Potenciais Evocados/efeitos dos fármacos , Haloperidol/farmacologia , Técnicas In Vitro , Canais Iônicos/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Neostriado/citologia , Neurônios/fisiologia , Técnicas de Patch-Clamp , Quimpirol/farmacologia , Ratos , Ratos Wistar , Sulpirida/farmacologia , Tetrodotoxina/farmacologiaRESUMO
Intracellular recordings from slice preparations were used to assess the subthreshold electrophysiological behavior of rat neostriatal projection neurons. Both current steps and ramp currents were used to estimate the current-voltage relationship (I-V plot). Inward rectification in the subthreshold range was a characteristic of most neurons. The amount of rectification varied greatly, and it was complex: membrane voltage trajectories in response to ramps were made up by almost piece-wise changes in the rate of voltage rise, suggesting that multiple conductances contribute to the subthreshold range. Inward current blockers such as tetrodotoxin (TTX) or Cd2+ decreased inward rectification, whereas outward current blockers such as tetraethylammonium (TEA) or 4-aminopyridine (4-AP) increased inward rectification. However, most inward rectification was due to TEA- and Cs(+)-sensitive conductances and not to TTX- or Cd(2+)-sensitive conductances. Cs(+)-sensitive conductances predominated at more negative membrane potentials, whereas 4-AP-sensitive conductances predominated at just +/- 10 mV below the firing threshold. In spite of a very slow activation, there was evidence for transient outward currents modulating the response, i.e., 4-AP-sensitivity, and voltage-sensitivity for firing frequency and threshold. TEA-sensitive conductances also contributed toward fixing the firing threshold. These results imply the contribution of various ion conductances on the shaping of the characteristic physiological firing recorded in vivo. Modulation of these responses by transmitters or peptides may help to understand neural processing in the neostriatum.
Assuntos
Neostriado/fisiologia , Neurônios/fisiologia , Potenciais de Ação/fisiologia , Animais , Apamina/farmacologia , Estimulação Elétrica , Eletrofisiologia , Potenciais Evocados/efeitos dos fármacos , Histocitoquímica , Técnicas In Vitro , Canais Iônicos/efeitos dos fármacos , Lisina/análogos & derivados , Potenciais da Membrana/fisiologia , Neostriado/citologia , Vias Neurais/citologia , Vias Neurais/fisiologia , Técnicas de Patch-Clamp , Ratos , Ratos WistarRESUMO
Suprarenal carcinoma is an unusual entity, rarely surpassing 4,000 gr. In general, tumors of such big size are not functional. We present a case of a 31-years-old woman with a suprarenal carcinoma weighting 5,200 gr, in which hormonal production was clinically and biochemically demonstrated.
Assuntos
Neoplasias das Glândulas Suprarrenais/diagnóstico , Neoplasias das Glândulas Suprarrenais/metabolismo , Neoplasias das Glândulas Suprarrenais/patologia , Adulto , Feminino , Humanos , RimRESUMO
Thirty one subjects are studied, 15 healthy (controls) and 16 presenting chronic alcoholic hepatopathy, in whom the existence of an autonomic insufficiency syndrome (AIS) was evaluated measuring the variations in heart rate while breathing (R index) and after standing up [O(B) index]. Vagal functioning was also studied when evaluating gastric emptying of digestible solids (VGS) and non digestible (VGSND). VGS after 45, 75 and 105 minutes in alcoholic patients was slower than in healthy controls (p less than 0.05) and in 50% of them it was slow after 105 minutes. VGSND was similar in both groups. R and O(B) indexes in alcoholic patients was smaller than in the control group (p less than 0.001), presenting 94% of them some index altered. An elevated percentage of patients suffering chronic alcoholic hepatopathy present a AIS which involves several organs, being R and O(B) indexes a better diagnostic method than VGS study.