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D M Campos

Publications and source records attributed to D M Campos.

17 recordsLinked to original sources
PubMed2001

Polarized expression of the GFP-tagged rat V(1a) vasopressin receptor.

We investigated the targeting of the V(1a) receptor fused with the green fluorescence protein (V(1a)R-GFP) in polarized MDCK cells. Cells expressing V(1a)R-GFP displayed binding to vasopressin (AVP) and AVP-induced calcium responses, similar to cells expressing the wild-type V1a receptor. Interestingly, as with the wild-type V(1a)R, V(1a)R-GFP is preferentially distributed in the basolateral side of MDCK cells as monitored by confocal microscopy. Furthermore, AVP induced internalization of GFP-tagged receptors. Therefore, the GFP-tagged V(1a) receptor retains all the sorting signals of the wild-type receptor and offers an excellent system to elucidate the mechanisms of cell trafficking of V(1a) receptors.

Animals↗
PubMedDate not supplied

Experimental life cycle of Lagochilascaris minor Leiper, 1909.

The life cycle of Lagochilascaris minor was studied using material collected from human lesion and applying the experimental model: rodents (mice, hamsters), and carnivores (cats, dogs). In mice given infective eggs, orally, hatch of the third stage larvae was noted in the gut wall, with migration to liver, lungs, skeletal musculature and subcutaneous tissue becoming, soon after, encysted. In cats infected with skinned carcasses of mice (60 to 235 days of infection) it was observed: hatch of third stage larvae from the nodules (cysts) in the stomach, migration through the oesophagus, pharynx, trachea, related tissues (rhino-oropharynx), and cervical lymph nodes developing to the mature stage in any of these sites on days 9-20 post inoculation (P.I.). There was no parasite development up to the mature stage in cats inoculated orally with infective eggs, which indicates that the life cycle of this parasite includes an obligatory intermediate host. In one of the cats (fed carcass of infected mice) necropsied on day 43 P.I., it was observed the occurrence of the self-infective cycle of L. minor in the lung tissues and in the cervical region which was characterized by the finding of eggs in different stages of development, third stage larvae and mature worms. It's believed that some component of the carnivore gastrointestinal tracts may preclude the development of third stage larvae from L. minor eggs what explains the interruption of the life cycle in animals fed infective eggs. It's also pointed out the role of the intermediate host in the first stages of the life cycle of this helminth.

Animals↗
PubMedDate not supplied

Cryo-microtome sections of coproculture larvae of Strongyloides stercoralis and Strongyloides ratti as antigen sources for the immunodiagnosis of human strongyloidiasis.

Cryo-microtome sections of larvae of Strongyloides stercoralis and S. ratti respectively obtained from human and rat feces cultures, were used as antigens. Fluoresceinate conjugates against human IgG were employed at the ideal titer of 10 for S. stercoralis and 100 for S. ratti. The sensitivity of the indirect immunofluorescence reaction (IIF) was 94.4% and 92.5% and the specificity 94.2% and 97.1% for the two specific larval antigens, respectively. Sera from 123 persons (54 from carriers of S. stercoralis infections and 69 from controls) were submitted to the reaction. The titers of different sera varied from 20 to 2560. There was a significant linear correlation (r = 0.85 p < or = 0.001) between the antibodies from the two species of larval antigens. We conclude that both antigens may be used in the IIF reaction for the diagnosis of human strongyloidiasis. Due to the feasibility of safe and low-cost mass production of S. ratti larvae in the laboratory with a considerable economy of conjugate, their utilization in the serum diagnosis of human strongyloidiasis is recommended.

Animals↗
PubMedDate not supplied

Assessment of ivermectin therapeutic efficacy on third-stage larvae of Lagochilascaris minor in mice experimentally infected.

In this study we evaluated the potential action of ivermectin on third-stage larvae, both at migratory and encysted phases, in mouse tissues after experimental infection with Lagochilascaris minor. Study groups I and II consisted of 120 mice that were orally administered 1,000 parasite eggs. In order to assess ivermectin action upon migratory larvae, group I (60 mice) was equally split in three subgroups, namely I-A, I-B, and I-C. On the 7th day after inoculation (DAI), each animal from the subgroup I-A was treated with 200 micrograms/Kg ivermectin while subgroup I-B was given 1,000 micrograms/Kg, both groups received a single subcutaneous dose. To assess the drug action on encysted larvae, group II was equally split in three subgroups, namely II-A, II-B, II-C. On the 45th DAI each animal was treated with ivermectin at 200 micrograms/Kg (subgroup II-A) and 1,000 micrograms/Kg (group II-B) with a single subcutaneous dose. Untreated animals of subgroups I-C and II-C were used as controls. On the 60th DAI all animals were submitted to larva search. At a dose of 1,000 micrograms/Kg the drug had 99.5% effectiveness on third-stage migratory larvae (subgroup I-B). Ivermectin efficacy was lower than 5% on third-stage encysted larvae for both doses as well as for migratory larvae treated with 200 micrograms/Kg.

Animals↗
PubMedDate not supplied

Parasitological and immunological diagnoses of strongyloidiasis in immunocompromised and non-immunocompromised children at Uberlândia, State of Minas Gerais, Brazil.

Parasitological and immunological diagnoses were part of a study conducted among 151 children, 83 immunocompromised (IC) and 68 non-immunocompromised (non-IC) aged from zero to 12, seen at the University Hospital, Universidade Federal de Uberlândia, State of Minas Gerais, Brazil, from February, 1996, to June, 1998. Three fecal samples from each child were analyzed for the parasitological diagnosis by Baermann-Moraes and Lutz methods. The immunological diagnosis to detect IgG and IgM antibodies was carried out by the indirect immunofluorescence antibody test (IFAT) with cryo-microtome sections of Strongyloides stercoralis and Strongyloides ratti larvae as antigens and by the ELISA test with an alkaline extract of S. ratti as the antigens. Of the 151 children 5 (3.31%) were infected with larvae of S. stercoralis (2 cases IC, 2.41%, and 3 cases non-IC, 4.41%). The IFAT-IgG detected 7 (8.43%) serum samples positive among IC, and 2 (2.94%) cases among non-IC. The ELISA-IgG test detected 10 (12.05%) serum samples positive among IC, and 1 (1.47%) case among non-IC. The IFAT-IgM detected 6 (7.22%) positive cases among IC, and 3 (4.41%) cases among non-IC. ELISA-IgM test detected 10 (12.05%) positive cases among IC, and 3 (4.41%) cases among non-IC. It was concluded that the immunological tests can help in the diagnosis of strongyloidiasis in immunocompromised children.

Animals↗
PubMedDate not supplied

[Visceral larva migrans. Report of 3 cases].

We report three cases of children with visceral larva migrans confirmed by enzyme-linked immunosorbent assay (ELISA), in Goiânia. Pulmonary interstitial infiltrates with dry cough and peripheral eosinophilia characterised the first case. Clinical and laboratorial finding in the second case included dry cough, pulmonary infiltrates, peripheral eosinophilia and hypergammaglobulinaemia. A persistent eosinophilia, between 1987-1989, without apparent cause led to the confirmation of parasite infection in the third case.

Child↗
PubMedDate not supplied

[Assessment of ivermectin therapeutic efficacy on fourth-stage larvae of Lagochilascaris minor in experimentally infected cats].

In order to verify the action of ivermectin against fourth-stage larvae of Lagochilascaris minor, thirty cats were divided into three groups (I, II and III). Each animal was inoculated orally with 50 third-stage larvae. The cats from groups I and II were treated with Ivermectin (200/microg/kg/single dose/sc via) on fifth day after inoculation (DAI). Treatment evaluation was performed between 30 and 40 DAI (group I) and between 180 to 190 DAI (group II) using parasite macroscopic and microscopic research at autopsy. The 10 cats from group III were untreated (control group). The authors observed 100% drug efficacy, at all observation periods, by total interruption of parasite's biological cycle in each of the treated animals. All the control group developed Lagochilascaris minor infection.

Animals↗
PubMedDate not supplied

Wild rodents as experimental intermediate hosts of Lagochilascaris minor Leiper, 1909.

A total of 25 specimens of Cavia porcellus (guinea pig), 5 Dasyprocta agouti (agouti), and 22 Calomys callosus (vesper mice) were inoculated with infective eggs of Lagochilascaris minor. The inoculum was prepared with embryonated eggs and orally administered to each individual animal through an esophagus probe. In parallel, 100 specimens of Felis catus domesticus were individually fed with 55-70 nodules containing 3rd-stage larvae encysted in tissues of infected rodents. Animals were examined and necropsied at different time intervals. The migration and encystment of L3 larva was observed in viscera, skeletal muscle, adipose and subcutaneous tissues from all rodents. Adult worms localized at abscesses in the cervical region, rhino, and oropharynx were recovered from domestic cats inoculated with infected rodent tissues. Through this study we can conclude that: (1) wild rodents act as intermediate hosts, characterizing this ascarid heteroxenic cycle; (2) in natural conditions rodents could possibly act as either intermediate hosts or paratenic hosts of Lagochilascaris minor; (3) despite the occurrence of an auto-infecting cycle, in prime-infection of felines (definite hosts) the cycle is only completed when intermediate hosts are provided; and (4) in the wild, rodents could serve as a source of infection for humans as they are frequently used as food in regions with the highest incidence of human lagochilascariasis.

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PubMedDate not supplied

[Nuclear syndrome of the oculomotor nerve caused by a mesencephalic infarction confirmed by MRI].

The nuclear syndrome of the third nerve was first described in 1981. It has the very characteristic disturbance of an ophthalmoplegia with complete ipsilateral third nerve palsy associated with paresis of elevation in contralateral eye. This particularly presentation is due to the innervation of the superior rectus which comes mainly from the contralateral oculomotor nucleus. As associated signs were described contralateral cerebellar and or pyramidal syndromes, uni or bilateral parasympathetic disfunction and sometimes gaze disorders. The etiology es usually a vascular damage (ischemic most frequently) located in mesencephalon. We report on a case of a 60 years old man who developed acute nuclear ophthalmoplegia of the third right nerve accompanied with cerebellar and pyramidal syndrome and focal asterixis in left extremities. MRI showed an ischemic lesion in right paramedial mesencephalic territory with extension to the ipsilateral thalamic region. Pyramidal and cerebellar syndromes and asterixis disappeared in a few weeks, while ophthalmoplegia remained unchanged. Semiologic characteristics and anatomic basis of the nuclear oculomotor syndrome which allow to make the differential diagnosis between this syndrome and intra-axial fascicular disturbances of the third nerve (Weber, Claude and Benedikt syndromes) are discuss.

Cerebral Infarction↗
PubMedDate not supplied

[Recurrent confusional states and periodic lateralized epileptiform discharges: a new type of non-convulsive status epilepticus?].

Periodic lateralized epileptiform discharges (PLEDs) in an EEG usually indicate the presence of an underlying structural lesion (of vascular origin in most cases). PLEDs are also sometimes observed in certain types of infections (mainly viral), in which they may even constitute a characteristic finding useful for diagnostic purposes. In recent years cases have been reported in which PLEDs are linked to recurring confusional states that do not fit in with established classifications and that may be epileptic in nature. We discuss the cases of 2 patients who were repeatedly admitted to our hospital in confusional states, in whom PLEDs were observed in EEG readings. Clinical evolution in both cases paralleled EEG alterations. We were able to perform both critical and intercritical single proton emission tomography on 1 patient, finding, respectively, hyper- and hypoabsorption foci. Symptoms resolved with antiepileptic treatment.

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