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G Grimaldi Júnior

Publications and source records attributed to G Grimaldi Júnior.

At least 19 recordsLinked to original sources
PubMed2003

Epidemiological and clinical features of Leishmania (Viannia) braziliensis American cutaneous and mucocutaneous leishmaniasis in the State of Espírito Santo, Brazil.

Between 1985 and 2000, epidemiological surveys of the American tegumentary leishmaniasis (ATL) were carried out in several rural and urban communities in Espírito Santo, Brazil. A total of 100 stocks of Leishmania (comprising isolates from both human and canine hosts with ATL) were identified by two methods of molecular characterization, using specific monoclonal antibodies and multilocus enzyme electrophoresis. Parasite isolates from 19 municipalities were found to belong to the same zymodeme and serodeme type as of the Leishmania (Viannia) braziliensis reference strain. In contrast, our genotyping studies have shown intra-specific variation among these parasites (comparisons of the variability of the internal transcribed spacers between the small and large subunits of the rRNA genes of the 22 stocks studied revealed at least 11 genotypes). Two main clusters of L. (V.) braziliensis genotypes were observed, representing parasites collected from different endemic regions in the state, where transmission reflects distinct eco-epidemiological features. Infection with this pathogen was associated with the characteristic disease forms, but neither the clinical outcome nor the response to treatment could be related to the genetic polymorphism of the isolates, as defined by using the proposed methodology.

Adolescent↗
PubMed1997

Development of Endotrypanum (Kinetoplastida:Trypanosomatidae) in experimentally infected phlebotomine sand flies (Diptera:Psychodidae).

The developmental biology (parasite establishment, migration, and differentiation) of Brazilian strains of Endotrypanum are reported for 3 sand fly species: Lutzomyia longipalpis Lutz & Neiva, L. shannoni Dyar, and Phlebotomus papatasi Scopoli. Laboratory-reared sand flies were infected by feeding on a promastigote suspension through a chick-skin membrane. Infections within the insect gut were examined at various times after feeding by staining fresh and fixed specimens. Development of Endotrypanum varied for each parasite-host species association. After feeding on culture forms of E. schaudinni Mesnil & Brimont (strain ISHA/BR/80/IM1111), significantly more L. shannoni (100%, 9/9) became infected than did L. longipalpis (62.3%, 33/53) or P. papatasi (27.3%, 15/55). The greatest number of infections were in the midgut and hindgut from 6 to 16 d after feeding, but flagellates also were present in the Malpighian tubules. Moreover, distinct development patterns in the sand fly gut were obtained when the Callejon L. longipalpis colony was fed on cultures of other Endotrypanum strains. Significantly fewer sand flies became infected with strain MCHO/BR/85/IM2259 (18.2%, 4/22) than with strain ISHA/BR/80/IM1111 (55.6%, 20/36). There were also individual variation in the distribution and survival of parasites within the guts of flies in each group. These data indicate that there is variation in the susceptibility to infection with Endotrypanum among and within sand fly species.

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PubMed1996

Enzyme polymorphism in Endotrypanum and numerical analysis of isoenzyme data.

In this study, we have analysed enzyme polymorphism among a group of protozoan parasites of the genus Endotrypanum (Kinetoplastida: Trypanosomatidae). Seventeen stocks of Endotrypanum spp. isolated from sloths (Choloepus didactylus and C. juruanus) in the Amazon Region of Brazil were analysed by enzyme electrophoresis, and their electromorphic profiles were compared with reference strains reported previously. The 16 enzymic loci were analysed, and the strains were classified into zymodemes, each representing parasites with unique enzyme profiles. Each zymodeme was considered as an elementary taxon, and using numerical analyses (cladistic, agglomerative hierarchical and ordination techniques) the genus was shown to be monophyletic and the 12 zymodemes characterized could be divided into 3 groups (A, B, C). The heterogeneous population (which may represent a complex of parasite species or strains variants) showed, however, no correlation with the origin (i.e. host species involved or geographic area of isolation) of Endotrypanum stocks. Eight isolates of Endotrypanum sp. from Rondônia State (Brazil) and a parasite strain from Panama were clustered together into a zymodeme, which was phenetically closely related to the E. monterogeii from Costa Rica. The data indicate that E. schaudinni is a species complex.

Animals↗
PubMed1996

Disseminated American cutaneous leishmaniasis.

BACKGROUND: While studying cutaneous leishmaniasis in the central part of western Venezuela, we found four cases of disseminated American cutaneous leishmaniasis, three from the Lara State and one from Portuguesa State. METHODS: A clinical history was taken for each of these patients, followed by microscopic examination of the Giemsastained smears from their cutaneous lesions and by a Montenegro skin test. Serum from a skin lesion were grown in Novy-MacNeal-Nicolle medium (NNN). Hamsters were inoculated with suspension of tissues taken from the patient's lesions. Biopsies were taken for histopathologic examination. Isolates from cultures on NNN medium and from hamsters were subcultured in Schneider's medium for parasite identification, using molecular techniques. Treatment with injections of N-methyl glucamine antimonate, 25 mg/kg/day was prescribed for each patient for 20 consecutive days and, after a week of rest, a second course of injections was administered. RESULTS: Patients had disseminated papular, ulcerous, nodular, and ulceronodular lesions on the skin. Smears of the skin lesions from all of the patients showed abundant amastigotes within histiocytes or free in the tissues. The skin test was negative in two patients. On histopathologic examination of skin lesions, mainly numerous vacuolated histiocytes filled with amastigotes were observed. Isolates from all the patients were identified as Leishmania venezuelensis. One of the patients healed after treatment with N-methyl glucamine antimonate. The others were resistant to this therapy. CONCLUSIONS: Diffuse cutaneous leishmaniasis can be caused also by Leishmania venezuelensis. Patients with nodular lesions who presented a negative Montenegro skin test were more resistant to treatment with specific pentavalent antimonials.

Adolescent↗
PubMed1995

Intergenic region typing (IRT): a rapid molecular approach to the characterization and evolution of Leishmania.

In the New World, Leishmania of the Viannia subgenus cause both cutaneous and mucocutaneous disease. These parasites show considerable intra-species genetic diversity and variation, which complicates taxonomic classification and epidemiology. We have used the variability of the transcribed noncoding regions between the small and large subunit rRNA genes to examine relationships in this group. In a method termed intergenic region typing (IRT), PCR amplification products were obtained for the rapidly evolving 1-1.2-kb internal transcribed spacers (ITS) between the SSU and LSU rRNAs, from 50 parasites isolated from different hosts and geographic areas. Amplified DNAs were digested with 10 different enzymes, and fragment patterns compared after acrylamide gel electrophoresis. High levels of intra- and inter-specific variation were observed, and quantitative similarity comparisons were used to associate different lineages. A complex evolutionary tree was obtained. Some species formed tight clusters (L. equatorensis, L. panamensis, L. guyanensis, L. shawi), while L. braziliensis was highly polymorphic and L. naiffi showed intraspecific distances comparable to the largest obtained within all Viannia. L. colombiensis, L. equatorensis and L. lainsoni clearly represent distinct lineages. Good agreement was obtained with molecular trees based upon isoenzyme or mini-exon repeat sequence comparisons. Overall, IRT appears to be a superb method for epidemiological and taxonomic studies of Leishmania, being sensitive, rapid and quantitative while simultaneously revealing considerable molecular diversity. IRT could also be applied to other nonconserved intergenic regions, including those separating protein-coding genes.

Animals↗
PubMed1994

Proteinase activities during temperature-induced stage differentiation of species complexes of Leishmania.

We have examined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), using gelatin, bovine serum albumin (BSA) or human IgG as substrate, proteinase activities in cell lysates from selected species complexes of Leishmania. The inhibition of proteinase activity caused by the reagent L-trans-epoxysuccinylleucylamido(4-guanidino)butane (E-64), which is known to act only on cysteinyl proteinases, revealed a 31 kDa component of this class of enzymes in soluble, but not in membrane-enriched preparations, of either L. amazonensis or L. major-like parasites from the New World. The proteinase component was detectable in the leishmanial multiplicative promastigote stage (log phase) and its concentration apparently increased during the thermally induced transformation of promastigotes to amastigote-like forms in vitro. Comparative studies revealed that taxonomically distinct species complexes of Leishmania possess high amastigote cysteine proteinase activity. This feature, however, was lacking in other developmental stages of the species (L. braziliensis, L. chagasi, L. aethiopica, and L. donovani) analyzed. Furthermore, lesion amastigotes of L. amazonensis displayed ultrastructurally recognizable megasomes, but megasome-like or large multivesicular body organelles could be detected only in axenic amastigotes of both L. amazonensis and L. major-like species.

Animals↗
PubMed1993

Molecular evidence for the importation of Old World Leishmania into the Americas.

A brief review of work carried out by the laboratory on the systematics of trypanosomatids during the last three years is given. The principal line of research has been on the taxonomy of New World Leishmania and one of the topics studied has been the determination of the autochthonous origin of certain Leishmania species found in the New World. Controversy exists as to whether the etiological agent of American Visceral Leishmaniasis is indigenous. Here, we present evidence from enzyme electrophoresis and schizodeme analysis indicating that L. chagasi has a recent origin and that it is similar to L. infantum. We also describe L. major-like isolates which have been found in the New World and present evidence suggesting that some of these populations may have been imported into the Americas. Reference strains from the subgenus Viannia are examined and compared with other Old World and New World species by enzyme electrophoresis. The results are analyzed numerically and we show that the Viannia species are a group of parasites indigenous to the New World that cluster separately from other Leishmania species. The numerical analyses also indicate that the subgenus forms a monophyletic group in contrast to the subgenus Leishmania which appears to be polyphyletic.

Americas↗
PubMed1993

[Cutaneous parasitism by Leishmania (Leishmania) chagasi during South American visceral leishmaniasis].

Eighteen patients from the northeastern Brazilian State of Ceara with proven kala-azar were studied for evidence of skin parasitism: two had ulcerative or papular skin lesions and 16 had clinically normal skin. Punch biopsies (3 mm) of intact paraspinal subscapular skin were performed on all patients; in those with papular or ulcerative lesions biopsies also were taken from an active site. One of each of the subscapsular biopsies and half of each biopsy from an active lesion were studied; the other specimens were seeded on NNN Difco Blood Agar Base Medium for parasite culture. The biopsies revealed a discrete to intense mononuclear inflammatory infiltrate, predominantly perivascular in nature. No amastigotes were observed in any tissue sections but 7 of the 18 patients yielded promastigotes on skin culture identified by monoclonal antibodies and by enzyme electrophoresis as Leishmania (Leishmania) chagasi [L. (L.) chagasi]. The isolation of Leishmania (Leishmania) chagasi, the recognized aetiologic agent of visceral leishmaniasis in the New World, from the skin of nearly 40% of 18 AVL patients proves dermatotropism of L. (L.) chagasi occurs and may be frequent in neotropical human visceral leishmaniasis (AVL.). Infected persons with skin parasites could act as a reservoir of infection and allow human to human transmission.

Adolescent↗
PubMed1992

Lymphadenopathy associated with Leishmania braziliensis cutaneous infection.

Lymph node involvement by Leishmania during human cutaneous leishmaniasis was reported more than 90 years ago, but the importance of certain Leishmania strains in such dissemination remains largely speculative. We have examined 36 consecutively untreated cutaneous leishmaniasis patients early in their disease; 66.7% had enlarged lymph nodes. Patients with enlarged lymph nodes had higher anti-Leishmania immune responses than patients without such involvement, both at the IgG antibody level (mean +/- SD optical density at 492 nm = 0.163 +/- 0.089 versus 0.098 +/- 0.086; P = 0.009) and in skin test responses (12.4 +/- 10.2 mm versus 5.7 +/- 7.3; P = 0.03). Thirteen (62%) of 21 lymph node cultures and 16 (53%) of 30 cultures from cutaneous sites were positive for Leishmania. Eleven of 13 isolates from lymph nodes were characterized by a panel of monoclonal antibodies, and all were typed as L. braziliensis. Our findings stress the importance of L. braziliensis as an agent involved in the early invasion of the lymphatic system.

Adolescent↗
PubMed1991

Leishmaniasis in Bahia, Brazil: evidence that Leishmania amazonensis produces a wide spectrum of clinical disease.

One hundred fourteen Leishmania isolates from patients with different clinical forms of leishmaniasis in the State of Bahia, Brazil, were characterized by indirect radioimmune binding assay using specific monoclonal antibodies (serodeme analysis). Seventy-five of these isolates were also analyzed by enzyme electrophoresis, based on 11 enzyme loci; parasite species were compared, according to their characteristic zymodemes, to those of WHO Leishmania reference strains. All isolates could be classified into one of three species: Leishmania amazonensis (n = 40), L. braziliensis (n = 39) or L. chagasi (n = 35). The most interesting information obtained from this study is the realization that L. amazonensis is capable of producing a wide spectrum of disease in humans. Infection with this parasite was associated with many different clinical presentations, including cutaneous leishmaniasis [CL] (20/49 cases), mucocutaneous leishmaniasis [MCL] (5/13 cases) and, of special note, visceral leishmaniasis [VL] (11/46 cases), as well as four cases of post kalaazar dermal leishmaniasis [PKDL]. In situ tissue parasite characterization, by immunoperoxidase assay and employing anti-L. amazonensis amastigote monoclonal antibodies, confirmed the infection with this species in two cases of CL, one case of DCL, one case of MCL and one case of PKDL. Our results also demonstrate the difficulty of parasite differentiation based on clinical grounds, since at least L. amazonensis infection can be associated with all types of leishmanial diseases, and different Leishmania species may be associated with indistinguishable clinical presentations. Since leishmanial parasites may vary in their biological behavior or in their response to treatment, it is important that their identification be made by reliable methods.

Animals↗
PubMed1986

Concurrent human infection with Leishmania donovani and Leishmania braziliensis braziliensis.

In the suburban district of Campo Grande, Municipality of Rio de Janeiro (Brazil) cases of both Leishmania domovani and L. b. braziliensis infections occur. In March 1982 we examined a white male child, five years old, with fever, weight loss and distended abdomen, symptoms said to have started three months before. After the first month a papular lesion appeared on his forehead, rapidly increasing in size and becoming ulcerated: Parasites were isolated from both the ulcer and the bone marrow by culturing in BHI-agar with rabbit blood and a liquid overlay of modified LIT medium. Using the techniques of zymodeme analysis, schizodeme analysis and serodeme analysis using monoclonal antibodies, the parasite from the ulcer was identified as L. b. braziliensis and that from the bone marrow as L. donovani. This seems to be the first described case of concurrent infection of man with a visceral and cutaneous Leishmania. It indicates that, at least in humans, a previous infection with L. donovani does not protect against L. b. braziliensis. This result has important implications for the development of vaccines against leishmaniases.

Animals↗
PubMedDate not supplied

Antigenic differences of Leishmania amazonensis isolates causing diffuse cutaneous leishmaniasis.

Six geographically distinct isolates of Leishmania amazonensis causing diffuse cutaneous leishmaniasis (DCL) (from Bahia and Maranhão, in Brazil and Guarico, in Venezuela) were characterized by immunoblot analysis to see whether any geographical or strain-related differences existed in antigenic composition. Western blots of promastigote homogenates were reacted with polyclonal sera from patients infected with L. amazonensis with the various forms of clinical disease. The pattern of antigenic reactivity of these strains revealed the presence of shared antigenic components between geographically distinct L. amazonensis isolates causing DCL, when tested with the sera of the infected patients. In certain cases, however, some polyclonal sera also detected antigenic fractions unique to the strains examined. Variation was observed between the antigenic components of some isolates of L. amazonensis that were recognized by a single serum, and between the antigenic components of a single isolate of L. amazonensis that were recognized by the different patients' sera. However, no constant association was found between the antigenic components identified in these isolates and the geographical area of isolation. These results indicate that, although these parasites appear to be closely related antigenically, they also possess some strain-related antigenic differences.

Animals↗
PubMedDate not supplied

Canine visceral leishmaniasis in Rio de Janeiro, Brazil. Clinical, parasitological, therapeutical and epidemiological findings (1977-1983).

Forty dogs from the periphery of the city of Rio de Janeiro were studied. All dogs where diagnosed as positive for leishmaniasis either parasitologically and/or serologically. Among them, 19 came from areas where only Visceral Leishmaniasis (VL) occurs (Realengo, Bangu, Senador Camará). Clinical signs of the disease were seen in 36.8% of the cases, including emaciation - 100%, lymphadenopathy and depilation - 85.7%. The other 21 dogs came from an area (Campo Grande) where both diseases (VL, and American Cutaneous Leishmaniasis - ACL) occur. Clinical signs of the disease, mainly cutaneous or mucocutaneous ulcers were seen in 76.2% of the cases. Leishmania parasites were found in 39 cases: 22% in viscera, 42.5% in viscera and normal skin and 35% in cutaneous or mucocutaneous ulcers. All the Leishmania stocks isolated from dogs which came from Realengo, Bangu, Senador Camará (VL area), and from Campo Grande (VL + ACL area) were characterized as L. donovani (except in one case) according to their schizodeme, zymodeme and serodeme. The only stock characterized as L. b. braziliensis, was isolated from the lymph node of a dog from Campo Grande with visceral disease and without skin lesions. Antimony therapy attempted in eight Leishmania donovani positive dogs was unsuccessful.

Animals↗