Evolutionary Relationships of the Triatoma matogrossensis Subcomplex,the Endemic Triatoma in Central-Western Brazil,Based on Mitochondrial DNA Sequences

The phylogenetic relationships among species of Triatoma matogrossensis subcomplex ( T. baratai, T. guazu, T. matogrossensis, T. sordida, T. vandae, and T. williami) was addressed by using fragments of cytochrome oxidase I (COI), 16S rDNA (16S), and cytochrome b (Cytb) through Bayesian and parsimony analyses. We did not recover a monophyletic T. matogrossensis subcomplex, and their members were found clustered in three strongly supported clades, as follows: i) T. jurbergi + T. matogrossensis + T. vandae + T. garciabesi + T. sordida; ii) with T. guasayana as the sister group of clade (i); and iii) T. williami + T. guazu, however not closely related to the clade formed by the previously mentioned species. The other two endemic species from Central-Western Brazil, T. baratai and T. costalimai, were not recovered with strong clade support as related to other members of this subcomplex. Results call for a further revision in the classification of the subcomplexes within the genus Triatoma.     

High prevalence of Dopaminergic Premonitory Symptoms in migraine patients with Restless Legs Syndrome: a pathogenetic link?

In order to assess the prevalence of Dopaminergic Premonitory Symptoms (DPS) in migraine patients with Restless Legs Syndrome (RLS), we chose migraine patients from a large Italian clinical headache population previously investigated for an association between primary headaches and RLS. We evaluated a total sample of 164 patients with migraine, in particular 114 with migraine without aura (MO), 10 with migraine with aura (MA) and 40 with MO and MA in various combinations between them or with episodic tension-type headache (ETTH), defined as a “mixed group”. About 20% of all migraine patients referred at least one of the following DPS: yawning, nausea, somnolence or food craving, confirming data already indicated in the literature. Among migraine patients with RLS (25.6%), DPS were referred from about half of the patients (47.6%) compared to those without RLS (47.6% vs. 13.1%; p<0.001). Based on migraine subtype, patients with MO referred DPS (26.3%) more frequently compared to the MA group and “mixed group” (12.0%, p<0.05), particularly in the presence of RLS (63.0% vs. 20.0%, p<0.01). No statistical differences were found between clinical and demographic data of the subgroups or related to medical conditions investigated (anxiety, depression, sleep disorders, body mass index). It is interesting that the chances of having RLS in migraine patients were more than 5 times higher in the presence of DPS. These results could support a hypothetical dopaminergic imbalance in RLS and migraine, as the dopamine is involved in the pathogenesis of both disorders and it is responsible for the migraine DPS reported above.     

Presence of autoantibodies against small nuclear ribonucleoprotein epitopes in Chagas' patients' sera

We investigated the possibility that Chagas' patients develop an autoimmune response to human UsnRNPs (small nuclear ribonucleoprotein) or Sm epitopes. Using purified human UsnRNPs, we detected anti-human UsnRNPs antibodies in sera from patients suffering from Chagas' disease. The antibodies were also detected using peptide enzyme-linked immunosorbent assays containing the Sm-motif 1 domain. The latter technique showed that 61% (31/51) of the Chagas' patients' sera contained antibodies against Sm-motif 1. The detection of anti-UsnRNPs autoantibodies in Chagas' patients' sera strongly encourages further studies using animal models to determine how these autoantibodies appear. Received: 4 April 1998 / Accepted: 13 May 1998     

Absolute configuration and selective trypanocidal activity of gaudichaudianic acid enantiomers

Gaudichaudianic acid, a prenylated chromene isolated from Piper gaudichaudianum, has been described as a potent trypanocidal compound against the Y-strain of Trypanosoma cruzi. We herein describe its isolation as a racemic mixture followed by enantiomeric resolution using chiral HPLC and determination of the absolute configuration of the enantiomers as (+)-S and (-)-R by means of a combination of electronic and vibrational circular dichroism using density functional theory calculations. Investigation of the EtOAc extract of the roots, stems, and leaves from both adult specimens and seedlings of P. gaudichaudianum revealed that gaudichaudianic acid is biosynthesized as a racemic mixture from the seedling stage onward. Moreover, gaudichaudianic acid was found exclusively in the roots of seedlings, while it is present in all organs of the adult plant. Trypanocidal assays indicated that the (+)-enantiomer was more active than its antipode. Interestingly, mixtures of enantiomers showed a synergistic effect, with the racemic mixture being the most active.     

Antiprotozoal sesquiterpene pyridine alkaloids from Maytenus ilicifolia

As part of a bioprospecting program aimed at the discovery of antiprotozoal agents from the Brazilian flora, two new sesquiterpene pyridine alkaloids, ilicifoliunines A (1) and B (2), along with the known alkaloids aquifoliunine E-I (3) and mayteine (4), were isolated from the root bark of Maytenus ilicifolia. The structures of 1 and 2 were established on the basis of spectroscopic data interpretation. Alkaloid 3 displayed potent in vitro antiprotozoal activity against Leishmania chagasi and Trypanosoma cruzi, with IC(50) values of 1.4 and 41.9 μM, respectively, as well as low cytotoxicity against murine peritoneal macrophages (IC(50) of 1.8 mM).     

Transjugular intrahepatic portosystemic shunt and liver transplantation

Transjugular intrahepatic portosystemic stent shunting (TIPSS) appears to be an attractive, nonsurgical procedure to overcome complications of end-stage liver disease. During the period August 1992 to February 1995, 23 adults who had previously undergone TIPSS received liver transplants. These patients were compared to 36 cirrhotic patients, grafted during the same time period, in relation to the implantation technique, the intraoperative use of blood products, and the length of their hospital stay. These groups were comparable for previous right upper quadrant surgery, splanchnic vein modifications, and Child-Pugh classification. Liver transplantation was performed electively in all TIPSS patients. Ten patients (43.4%) presented with a significant shunt stenosis at a median follow-up time of 4.5 months (range 2.5 to 30 months). At transplantation 8 of the 23 TIPSS patients (34.8%) had specific TIPSS-related modifications i.e., extrahepatic portal vein aneurysm formation (n=2), dislocation of the distal end of the stent into the inferior vena cava (n=4) or into the main portal vein trunk (n=1), bilioportal fistula (n=1), and pronounced phlebitis of the inferior vena cava and hepatic veins due to redilation of shunt stenosis (n=4). The intraoperative blood product requirement at transplantation was similar in the 23 TIPSS-patients and in the 36 cirrhotic patients who received transplants without the TIPSS procedure during the same time period [median 800 ml (range 0–20300 ml) vs median 620 ml (range 0–7600 ml), respectively]. There was also no difference between the two groups in length of hospital stay [median 18 days (range 0–34 days) vs median 19 days (range 0–66 days), respectively]. We conclude that TIPSS plays an important role in the management of life-threatening complications of end-stage liver disease arising in potential liver transplant candidates. TIPSS should be considered as a temporary, effective bridge to elective transplantation and not as a means to lower the blood product requirement at transplantation. Specific TIPSS-related modifications should be recognized early by the transplant surgeon in order to adapt the technique of graft implantation.     

Post-apopletic trigeminal trophic syndrome

Trigeminal trophic syndrome is an uncommon clinical entity in which cutaneous trophic ulceration develops with continuous manipulation of trigeminal dermatomes. Patients spontaneously refer picking, rubbing and/or scratching at the affected areas because of hypo-anaesthesia, paraesthesia and/or pain following damage of the sensory trigeminal fibres or nuclei. We herein describe a patient who developed the syndrome as a sequela of brain stem infarction. Diagnosis by scrape cytology in ruling-out basal cell carcinoma and other ulcerative skin diseases is discussed and the importance of neurological examination in disclosing hemi-anaesthesia of trigeminal dermatome(s) is emphasized.