Distribución geográfica de los triatominos en el oriente del Perú / Geographic distribution of triatomines in east of Peru

Se nota la distribución geográfica de nueve especies de triatominae (Hemiptera, Reduviidae) en la zona oriental del Perú constituida por los departamentos de Amazonas, Loreto, San Martín, Ucayali y Madre de Dios; ellas son: Triatoma nigromaculata, Panstrongylus chinai, P. herreri, P. geniculatus, P. lignarius, Eratyrus mucronatus, Rhodnius pictipes, R. robustus y Belminus peruvianus. La especie de mayor distribución es R. pictipes. Los autores hallaron a R. pictipes infectado en forma natural con Trypanosoma cruzi, a P. herreri y R. robustus con Trypanosoma sp

Purification and properties of the very high density lipoprotein from the hemolymph of adult Triatoma infestans.

The very high density lipoprotein (VHDL) of Triatoma infestans hemolymph from adult males has been isolated and purified by two-step density gradient ultracentrifugation. It appears to be homogeneous as judged by native polyacrylamide gel electrophoresis. The content of VHDL in hemolymph was estimated to be 8 mg protein/ml. The purified protein has a molecular weight (Mr) of 450,000, is composed of six subunits of Mr approximately equal to 77,000, and possesses a high content of aromatic amino acids. This protein is glycosylated and contains 3% of lipids by weight with a remarkable amount of free fatty acids (25% of total lipids). The T. infestans VHDL has a different lipid and amino acid composition from lipophorin. The lipid composition and the spectroscopic studies using cis-parinaric acid indicated a high fatty acid binding affinity. It has nine binding sites per mol of VHDL. Competence studies revealed that VHDL has its highest affinity for the binding of palmitic acid followed by stearic and arachidonic acids.

Polymorphic organization of the endoplasmic reticulum of the Malpighian tubule. Evidence for a transcellular route.

Isosmotic fluid absorption carried out by many mammalian epithelia appears to be similar to the isosmotic secretion of insect epithelia such as the Malpighian tubules, which are responsible for urine formation and osmoregulation. We have studied by electron microscopy (80 kV) the three-dimensional characteristics of organelles in the Malpighian tubules of Rhodnius prolixus using thick sections (0.3-0.5 microns) and uranyl and lead impregnation. The ER presents a different organization in the upper (distal) and lower (proximal) segments of the Malpighian tubule. In distal secretory segment, the ER forms a network made of chains of vesicles having irregular shapes (ca. 0.06 micron in diameter) connected to each other by canaliculi while in the lower absorptive segment, the ER is made of parallel saccules arranged in stacks or whorls in the central region of the cytoplasm. In both segments, the ER network extends throughout the cytoplasm from the basolateral infoldings to the apex between the many mitochondria present in these two areas. A unique feature of these cells, revealed by thick sections, is the presence in each microvillus of either a mitochondrion or an ER canaliculus in continuity with the ER network. The ER does not seem to have any specific association with mitochondria or other organelles. As in the mammalian nephron, this ER organization is most likely related to specific segmental functions and adds support to its potential role as a transcellular epithelial route.

The occurrence of arachidonic acid in Triatoma infestans.

1. Gas-liquid chromatography and mass spectrometry were used to verify the presence of arachidonic acid (20:4 omega 6) in adult male and female organs of the blood-suckling bug Triatoma infestans. Fat body, gonad and head lipids were analyzed. 2. Male gonads contained the highest percentage of phospholipids and the highest percentage of arachidonic acid. 3. Phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine and sphingomyelin were isolated from gonads and heads of sexed insects and the fatty acid composition analyzed. 4. All the phospholipids analyzed contained relevant percentages of linoleic acid and fair percentages of arachidonic acid, except for sphingomyelin where no 20:4 omega 6 acid was found. 5. However, arachidonic acid was specifically incorporated in phosphatidylinositol since this phospholipid contained very large percentages of the acid. 6. In male gonads, phosphatidylcholine also contained a similar high percentage of the acid. Arachidonic acid is apparently incorporated, selectively, into these lipids from the blood of the host.

[Biochemistry of the evolutive cycle of Triatoma infestans. IX. Composition of cuticular hydrocarbons compared to other Triatominae]. / Bioquímica del ciclo evolutivo del Triatoma infestans. IX. Composición de los hidrocarburos cuticulares comparada con otros triatominos.

The hydrocarbon composition of epicuticular lipids of different species of Triatomini were determined and compared by gas-liquid chromatography. T. infestans, T. delpontei, T. rubrovaria, T. sordida, T. guasayana and T. vitticeps from infestans subgroup and T. pallidipennis from rubrofasciata, were studied. All these species had in common the same kind of hydrocarbons. The major components were n C29; n C31; 12+14+15+18 methyl C38; 15, 19+14, 18 dimethyl C39; 12+14+17+19 methyl C36 and 4 methyl C34. However, the relative proportions of selective hydrocarbons were significantly different among the species studied. These differences may be used with a chemotaxonomic criterion. Either the gas-liquid chromatographic curve of the cuticular hydrocarbons or the ratio of selective hydrocarbons may be used as fingerprints of the species considered.

Vitellin and vitellogenin characterization of Triatoma infestans and related species.

The vitellogenin-vitellin (VG-VN) of Triatoma infestans is a glycolipoprotein with a mol. wt. of 220,000; is a high density lipoprotein (1.18-1.21 g/ml) with low electrophoretic mobility at pH 8.2. There are many common proteins present in females, males, nymphs and eggs, but none is a glycolipoprotein. The major band of protein revealed a mol. wt. of 43,000, it is an anodic protein which appears in all the fractions of saline gradient. Males and females have a glycolipoprotein with electrophoretic mobility similar to VG-VN, but it is a low density lipoprotein. Another VG-VN, cathodic, not glycolipoproteic, is present in eggs and female hemolymph. The major VG-VN could be isolated from other proteins by ultracentrifugation in BrNa gradient or by DEAE-cellulose chromatography. Several species of Triatoma have immunological identity between theirs VG-VN. Female and eggs of Panstrongylus megistus and females, males and eggs of Rhodnius prolixus have a glycolipoprotein with partial immunological identity with the VG-VN of Triatoma infestans.

Bioquímica del ciclo evolutivo del Triatoma infestans: IX. composición de los hidrocarburos cuticulares comparada con otros triatominos / Biochemistry of the evolutive cycle of Triatoma infestans: IX. Composition of cuticular hydrocarbons compared to other Triatominae

Se compara la composición de los hidrocarburos epicuticulares de varias especies de la tribu Triatomini: T. infestans, T. delpontei, T. rubrovaria, T. sordida, T. guasayana, T. vitticeps (subgrupo infestans) y T. pallidipennis (subgrupo rubrofasciata). Todas estas especies tienen una misma composión cualitativa donde los hidrocarburos mayoritarios son nC29, nC31, 12+14+15+18 metil C38, 15,19+14,18 dimetil C39, 12+14+17+19 metil C36 y 4 metil C34. Sin embargo, las proporciones en que ciertos hidrocarburos se encuentran en cada especie difieren significativamente entre sí y podrían ser utilizadas como criterio de taxonomía química para especies congenéricas bastante cercanas. Para ello podrían emplearse ya sea las curvas cromatográficas o los cocientes de las cantidades en que se presentan ciertos hidrocarburos

Bioquímica del ciclo evolutivo del Triatoma infestans: IX. composición de los hidrocarburos cuticulares comparada con otros triatominos / Biochemistry of the evolutive cycle of Triatoma infestans: IX. Composition of cuticular hydrocarbons compared to other Triatominae

Se compara la composición de los hidrocarburos epicuticulares de varias especies de la tribu Triatomini: T. infestans, T. delpontei, T. rubrovaria, T. sordida, T. guasayana, T. vitticeps (subgrupo infestans) y T. pallidipennis (subgrupo rubrofasciata). Todas estas especies tienen una misma composión cualitativa donde los hidrocarburos mayoritarios son nC29, nC31, 12+14+15+18 metil C38, 15,19+14,18 dimetil C39, 12+14+17+19 metil C36 y 4 metil C34. Sin embargo, las proporciones en que ciertos hidrocarburos se encuentran en cada especie difieren significativamente entre sí y podrían ser utilizadas como criterio de taxonomía química para especies congenéricas bastante cercanas. Para ello podrían emplearse ya sea las curvas cromatográficas o los cocientes de las cantidades en que se presentan ciertos hidrocarburos (AU)

[A new plasminogen activator isolated from the saliva of Rhapactor biparticeps (Heteroptera, Reduviidae): biological and physicochemical properties]. / Un nouvel activateur du plasminogène isolé à partir de la salive de Rhapactor biparticeps (Heteroptera, Reduviidae): Propriétés biologiques et Physicochimiques.

A new plasminogen activator has been isolated from the saliva of Rhapactor biparticeps. This product is 5% of salivary proteins and acts at an optimal pH of 7.8.P.D.F which results from its action on human fibrinogen are similar to those which are obtained with streptokinase. The modalities of action of this plasminogen activator on the fibrinogen are discussed.

[Identification of plasminogen activators in the saliva of Rhapactor biparticeps (Reduviidae)]. / Identification d'activateurs du plasminogène dans la salive de Rhapactor biparticeps (Reduviidae).

Plasminogen activators are identified in the saliva of Rhapactor biparticeps using a particular technique which includes human fibrin in polyacrylamide gel. This technique is described and results are discussed according to classical methods used for fibrinolysis studies.

Isolation and characterization of the haemolymph lipoproteins of Triatoma infestans.

1. Three lipoproteins differing in hydrated densities were isolated by ultracentrifugal procedures from the haemolymph of adult and fasted Triatoma infestans. 2. They are the high density lipoprotein HDL (d = 1.115-1.152) and the two very high density lipoproteins VHDL-I (d = 1.190-1.231) and VHDL-II (d = 1.245-1.260). HDL was the predominant lipoprotein. 3. The total lipid content expressed as % of lipoprotein weight in HDL, VHDL-I an VHDL-II was 30.1, 7.8 ad 2.9% respectively. Diacylglycerols are the predominant lipids of HDL (38.7%) and VHDL-I (27.0%) but only amount of 6.2% in VHDL-II. 4. Triacylglycerols are minor components (about 6.0%) of all fractions. 5. The phospholipids (phosphatidylethanolamine and phosphatidylcholine), sterols, sterol esters and hydrocarbons were present in all lipoprotein fractions. 6. Phospholipids and hydrocarbons were the most abundant lipids of VHDL-II.

Influence of organ extracts of Triatoma infestans on differentiation of Trypanosoma cruzi.

The influence that extracts of different T. infestans organs possess to induce Trypanosoma cruzi differentiation from epimastigotes to metacyclic forms in Grace's and modified Grace's media was analyzed. Growth of epimastigotes was adequate in Grace's medium when homogenates of stomach, testes, and ovaries from recently fed insects were added. Growth of epimastigotes was adequate when testes or ovaries obtained from recently fed triatomes were added to modified Grace's medium. Similar results were obtained in Grace's or modified Grace's media supplemented with stomach or intestinal homogenates obtained from "starved" triatomes. None of the above culture conditions induced differentiation of epimastigotes to the metacyclic stage. When extracts of intestine or stomach obtained from triatomes fed 24 to 48 hr previously were used to supplement the modified Grace's medium, growth and differentiation to the metacyclic stage was induced in a high percentage of the population. When extracts of intestine obtained from recently fed insects were used to supplement Grace's medium, differentiation and growth was an in modified Grace's medium. No important differences were observed if cultures were prepared at pH 6.4 or 7.0. The triatome food source did not seem to be important for the differentiation. The parasite population after differentiation to metacyclic type forms showed a higher degree of infectivity than the original population constituted mostly by epimastigotes. These studies suggest the importance of factors from the insect vector in differentiation of T. cruzi.

Toluidine blue binding capacity of heterochromatin and euchromatin of Triatoma infestans Klug.

The localization of the absorption peaks of toluidine blue-stained heterochromatin (Ho and Hs) and euchromatin (Eo and Es) of the Malpighian tubules of the blood-sucking hemipteran, Triatoma infestans Klug was studied cytophotometrically (Ho and Eo: hetero- and euchromatin of nuclei with one single chromocenter; Hs and Es: hetero- and euchromatin of nuclei with several chromocenters). shifts of the absorption peaks to longer wave-lengths were found for the euchromatin fractions and Hs after RNAse treatment. The differences in the localization of absorption peaks after RNAse digestion when comparing the various chromatin types with one another are assumed to be due to differences in the number and proximity of DNA phosphates unattached to proteins and hence available to dye binding. The localization of the absorption peak of Ho at a relatively short wavelength (lambda = 570 nm) as compared with those for Hs, Eo, and Es, is attributed to a special state of chromatin condensation and practically absence of RNA in Ho. Also a certain removal of histones (probably, Hl) by the acetic ethanol "fixation" is speculated to play a role in the absorption curve properties of Ho subjected to TB staining.

[Cytochemical data on histones of the heterochromatins and euchromatins of Triatoma infestans Klug (author's transl)]. / Dados citoquimicos sobre as histonas de heterocromatinas e eucromatinas do Triatoma infestans Klug.

In cells of the Malpighian tubes of Triatoma infestans Klug, the histone content reactive to the alkaline fast green method does not remarkably differ when nuclei with various heterochromatic patterns (T1 and T8) are compared to each other. The fast green-histone values for the euchromatins (and heterochromatins) of both nucleus types also appear not differing. However, the possibility that these histones are differently linked to DNA in euchromatin or heterochromatin variants is not to be ruled out. Cytochemical evidence is suggestive of a lysine-richness in the histones of the mentioned hetero- and euchromatins.