Acute myeloid leukemia with t(8; 21)(q22; q22) preceded by breast granulocytic sarcoma / Leucemia mielóide aguda com t(8; 21)(q22; q22) precedido de sarcoma granulocítico na mama

Granulocytic sarcoma (GS) is a rare extramedullary tumor mass composed of immature cells derived from the hematopoietic myeloid series. It is usually associated with leukemia and other myeloproliferative disorders but can also occur without overt hematologic diseases. The breast has been reported to be an uncommon site of presentation. We report a case of acute myeloid leukemia preceded by GS of the breast. The immunohistochemistry revealed myeloperoxidase, CD68 and CD43 positivity, thus indicating a diagnosis of GS. Conventional cytogenetic analysis of peripheral blood cells showed t(8;21)(q22;22). Complete remission was achieved with Daunorubicin and Cytarabine induction therapy followed by three courses of high-dose Cytarabine consolidation. The patient remains in continuous complete remission at 27 months.

Sarcoma granulocítico (GS) é um raro tumor extramedular composto de células imaturas derivadas das linhagens hematopoiéticasmielóides. É geralmente associada à leucemia ou outras desordens mieloproliferativas, mas também pode ocorrer sem manifestação de doenças hematológicas. A mama tem sido relatada como local incomum de apresentação. Relatamos um caso de leucemia mielóide aguda precedida por GS da mama. A imunohistoquímica revelou mieloperoxidase, CD68 e CD43 positivos, indicando um diagnóstico da GS. A análise citogenética convencional de células de sangue periférico mostrou t(8; 21)(q22; 22). Remissão completa foi atingida com indução terapêutica com daunorubicina e citarabina, seguida de três ciclos de alta dose de citarabina. O paciente permanece em completa remissão há 27 meses.

Possible analgesic effect of vigabrin in animal experimental chronic neuropathic pain

Since anticonvulsants have been used for treating neuralgias, an interest has arisen to experimentally test vigabatrin for its gabaergic mechanism of action. For this, 41 Wistar rats were used, and in 25 of them a constractive sciatic neuropathy was induced (Bennet & Xie model). For testing pain symptoms, spontaneous (Scratching) and evoked behaviors to noxious (46 degrees Celsius) and non-noxious (40 degrees Celsius) thermal stimuli were quatified. Moreover, a comparative pharmacological study of vigabatrin with other analgesic anticonvulsant drugs was also performed. The results showed a possible dose-dependent analgesic effect of vigabatrin (gamma-vinyl-GABA) on experimental neuropathic pain, as shown vy the significant (p<0.05) decreasing effect of vigabatrin on scratching and by its significant (p>0.05) increasing effect on the latency of the right hindpaw withdrawal of the animals to noxious thermal stimulus. This was corroborated by similar findings with analgesic anticonvulsants (carbamazepine, phenytoin and valproic acid). This possible and not yet described analgesic effect of vigabatrin seems not to be opioid mediated.

The effect of baclofen on spontaneous and evoked behavioral expression of experimental neuropathic chronic pain

Baclofen (Beta-p-chlorophenyl-GABA) has been used in humans to treat spasticity, as well as trigeminal neuralgia Since GABA (gamma-aminobutyric acid) has been implicated in inhibitory and analgesic effects in the nervous system, it was of interest to study the effect of baclofen in experimental neuropathic pain. With this purpose, experiments were carried out in 17 neuropathic rats with constrictive sciatic injury, as described by Bennet and Xie (1988), taking as pain parameters scratching behaviour and the latency to the thermal nociceptive stimulus. The results showed that baclofen induces, in a dose-dependent manner, significant decrease (p<0.05) of scratching behaviour and significant increase (p<0.05) of the latency to the nociceptive thermal stimulus. The absence of antagonism of naloxone suggested a non-participation of an opioid-mediated mechanism in this analgesic effect of baclofen on experimental neuropathic pain.

Experimental HTLV-1 infection and associated myelopathy

HTLV-I infection and associated myelopathy has been reproduced experimentally in vitro and in vivo and these studies have shown the possibility of creating several lines of infective cells and of detecting minor and major clinical expressions of HTLV-I associated myelopathy in rabbits and rats.