Dopamine depletion in wistar rats with epilepsy

The dopamine content in cerebral structures has been related to neuronal excitability and several approaches have been used to study this phenomenon during seizure vulnerability period. In the present work, we describe the effects of dopamine depletion after the administration of 6-hidroxidopamine (6-OHDA) into the substantia nigra pars compacta of male rats submitted to the pilocarpine model of epilepsy. Susceptibility to pilocarpine-induced status epilepticus (SE), as well as spontaneous and recurrent seizures (SRSs) frequency during the chronic period of the model were determined. Since the hippocampus is one of main structures in the development of this experimental model of epilepsy, the dopamine levels in this region were also determined after drug administration. In the first experiment, 62% (15/24) of 6-OHDA pre-treated rats and 45% (11/24) of those receiving ascorbic acid as control solution progressed to motor limbic seizures evolving to SE, after the administration of pilocarpine. Severeness of seizures during the model´s the acute period, was significantly higher in epileptic experimental rats (56.52%), than in controls (4.16%). In the second experiment, the frequency of seizures in the model's chronic phase did not significantly change between groups. Our data show that dopamine may play an important role on seizure severity in the pilo's model acute period, which seems to be due to dopamine inhibitory action on motor expression of seizure.

Case report: Interference from isatuximab on serum protein electrophoresis prevented demonstration of complete remission in a myeloma patient

Multiple myeloma is a haematological cancer caused by malignant plasma cells in the bone marrow that can result in organ dysfunction and death. Recent novel treatments have contributed to improved survival rates, including monoclonal antibody therapies that target the CD38 protein on the surface of plasma cells. Anti-CD38 therapies are IgG kappa monoclonal antibodies that are given in doses high enough for the drug to be visible on serum protein electrophoresis as a small paraprotein. We present a case where isatuximab, the most recent anti-CD38 monoclonal antibody to be approved for treatment of myeloma, obscured the patient's paraprotein on gel immunofixation, so that complete remission could not be demonstrated. This was resolved using the isatuximab Hydrashift assay. The interference on gel immunofixation was unexpected because isatuximab migrated in a position distinct from the patient's paraprotein on capillary zone electrophoresis. We demonstrate the surprising finding that isatuximab migrates in a different position on gel electrophoresis compared to capillary zone electrophoresis. It is vital that laboratories are aware of the possible interference on electrophoresis from anti-CD38 monoclonal antibody therapies, and are able to recognise these drugs on protein electrophoresis. The difference in isatuximab's electrophoretic mobility on capillary and gel protein electrophoresis makes this particularly challenging. Laboratories should have a strategy for alternative analyses in the event that the drugs interfere with assessment of the patient's paraprotein.

Accuracy of ultrasound and clinical examination in the diagnosis of axillary lymph node metastases in breast cancer

To evaluate the accuracy of ultrasound regarding the axilla using a 3.5 mHz linear probe, a retrospective study was conducted including 115 cases of breast cancer. The clinical examination was more sensitive than echography (68% vs 56%), but not significantly. The ultrasound presented a higher specificity (89% vs 68% P less than 0.05). The positive predictive values were 82% and 92% for clinical examination and ultrasound respectively and the negative predictive values were 50% and 49%. The total accuracy was 68% for the clinical examination and 67% for the echography (NS). Breaking the data into two groups, those with up to three nodes involved and those with four or more, the analysis showed that either the sensitivity of the clinical examination in the second group or the specificity of the ultrasound in both groups, was significantly higher (P less than 0.05). Nevertheless there was no difference in the total accuracy between the two methods in either group. The results suggest that probes with this resolution have not helped clinical examination in the evaluation of the axilla and even the simultaneous use of both methods may fail in one-third of the cases with lymph node metastases.

Reaction of rectal mucosa of celiac patients to direct contact with gluten

It is assumed that the colonic mucosa of celiac patients is not sensitive to gluten. This assumption has been supported by the absence of clinical manifestations of colonic involvement in patients with active celiac disease which, by itself, does not confirm insensitivity to gluten. Eight children, aged from 11 to 25 months, with an initial diagnosis of celiac disease were studied: in five children a definite diagnosis has already been confirmed. Rectal gluten challenge was done by means of retention enemas. A volume of 100 ml of a 10% gluten suspension in water was introduced into the rectum three times per day for 8 days; each enema was retained at least 1 h. Rectosigmoidoscopies and rectal biopsies were done before and at the end of the challenge period. The endoscopic appearance of rectal mucosa was normal in all the children either before or after gluten challenge. The means of total mucosal thickness, intraepithelial lymphocyte counts, mitotic crypt cell activity, and cellular infiltration of lamina propria increased after challenge; the mean of goblet cell/epithelial cell ratio in the surface epithelium decreased. The differences between each pair of means (before and after challenge), however, were not significant except for total mucosal thickness (p less than 0.05), the meaning of which is unclear. This study did not definitely demonstrate that the rectal mucosa of celiacs is insensitive to gluten. For practical clinical purposes, however, it behaves as such. This makes the rectal mucosa a useless tool for the final diagnosis of celiac disease.