The Chemical Compositions of Essential Oils Derived from Cryptocarya alba and Laurelia sempervirens Possess Antioxidant, Antibacterial and Antitumoral Activity Potential.

Cryptocarya alba (Peumo; CA) and Laurelia sempervirens (Laurel; LS) are herbs native to the Chilean highlands and have historically been used for medicinal purposes by the Huilliches people. In this work, the essential oils were extracted using hydrodistillation in Clevenger apparatus and analyzed by GC-MS to determine their composition. The antioxidant capacity (AC) was evaluated in vitro. The cytotoxicity was determined using cell line cultures both non tumoral and tumoral. The toxicity was determined using the nematode Caenorhabditis elegans. The antimicrobial activity was evaluated against 52 bacteria using the agar disc diffusion method and the minimum inhibitory concentrations (MICs) were determined. The principal compounds found in C. alba essential oil (CA_EO) were α-terpineol (24.96%) and eucalyptol (21.63%) and were isazafrol (91.9%) in L. sempervirens essential oil (LS_EO). Both EOs showed antioxidant capacity in vitro. Both EO showed antibacterial activity against bacteria using. LS_EO showed more inhibitory effect on these cell lines respect to CA_EO. Both EOs showed toxicity against the nematode C.elegans at 3.12-50 mg/mL. The essential oils of CA and LS have an important bioactive potential in their antioxidant, antibacterial and cytotoxicity activity. Both essential oils could possibly be used in the field of natural medicine, natural food preservation, cosmetics, sanitation and plaguicides among others.

Use of Phycobiliproteins from Atacama Cyanobacteria as Food Colorants in a Dairy Beverage Prototype.

The interest of the food industry in replacing artificial dyes with natural pigments has grown recently. Cyanobacterial phycobiliproteins (PBPs), phycoerythrin (PE) and phycocyanin (PC), are colored water-soluble proteins that are used as natural pigments. Additionally, red PE and blue PC have antioxidant capabilities. We have formulated a new food prototype based on PBP-fortified skim milk. PBPs from Andean cyanobacteria were purified by ammonium sulfate precipitation, ion-exchange chromatography, and freeze-drying. The stability of PE and PC was evaluated by changes in their absorption spectra at various pH (1-14) and temperature (0-80 °C) values. Purified PBPs showed chemical stability under pH values of 5 to 8 and at temperatures between 0 and 50 °C. The antioxidant property of PBP was confirmed by ABTS (2,2'-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical ion scavenging, and FRAP (Ferric Antioxidant Power) assays. The absence of PBP toxicity against Caenorhabditis elegans was confirmed up to 1 mg PBP/mL. Skim milk fortified with PE obtained a higher score after sensory tests. Thus, a functional food based on skim milk-containing cyanobacterial PBPs can be considered an innovative beverage for the food industry. PBPs were stable at an ultra-high temperature (138 °C and 4 s). PBP stability improvements by changes at its primary structure and the incorporation of freeze-dried PBPs into sachets should be considered as alternatives for their future commercialization.

Comparison of Total Anaerobic Microbiota in Periodontitis Before and After the Subgingival Irrigation with Chlorhexidine at 0. 12 % / Comparación de la Microbiota Anaerobia Total en Periodontitis antes y Después de la Irrigación Subgingival con Clorhexidina al 0, 12 %

ABSTRACT: The objective of this study was to determine the effect of the subgingival irrigation of chlorhexidine 0.12 % of the total anaerobic microbiota. Microbial sampling to 30 subjects with periodontitis stage II Grade B, in pockets with a periodontal probing depth > 4 mm. The subgingival irrigation was made with 5 mL of chlorhexidine in the test group and with 5 mL of distilled water in the control group. 24 hours after the procedure was obtained a second sample to compare. It was found that the subgingival irrigation with chlorhexidine at 0.12 % achieved a statistically significant decrease in anaerobic microbiota (p< 0.05).

RESUMEN: El objetivo del presente estudio fue determinar el efecto de la irrigación subgingival de la clorhexidina 0,12 % sobre la microbiota anaeróbica total. Se tomaron muestras microbiológicas a 30 sujetos con periodontitis estadio II grado B, en sacos periodontales con una profundidad de sondaje > 4 mm. Se realizó la irrigación subgingival con 5 mL. de clorhexidina en el grupo test y con 5 mL. de agua destilada en el grupo control. 24 horas después del procedimiento se obtuvo una segunda muestra a comparar. Se detectó que la irrigación subgingival con clorhexidina al 0,12 % logra disminuir en forma estadísticamente significativa la microbiota anaeróbica total (p< 0,05).

Decreased cruzipain and gp85/trans-sialidase family protein expression contributes to loss of Trypanosoma cruzi trypomastigote virulence.

Two cell lines derived from a single Trypanosoma cruzi clone by long-term passaging generated a highly virulent (C8C3hvir) and a low virulent (C8C3lvir) cell line. The C8C3hvir cell line was highly infective and lethal to Balb/c mice, and the C8C3lvir cell line was three- to five-fold less infective to mouse cardiomyocytes than C8C3hvir. The highly virulent T. cruzi cell line abundantly expressed the major cysteine proteinase cruzipain (Czp), complement regulatory protein (CRP) and trans-sialidase (TS), all of which are known to act as virulence factors in this parasite. The in vitro invasion capacity and in vivo Balb/c mouse infectiveness of the highly virulent strain was strongly reduced by pre-treatment with antisense oligonucleotides targeting TS or CRP or with E64d. Based on these results, we conclude that decreased levels of TS, CRP and Czp expression could contribute to loss of T. cruzi trypomastigote virulence.

A cytoplasmic new catalytic subunit of calcineurin in Trypanosoma cruzi and its molecular and functional characterization.

Parasitological cure for Chagas disease is considered extremely difficult to achieve because of the lack of effective chemotherapeutic agents against Trypanosoma cruzi at different stages of infection. There are currently only two drugs available. These have several limitations and can produce serious side effects. Thus, new chemotherapeutic targets are much sought after. Among T. cruzi components involved in key processes such as parasite proliferation and host cell invasion, Ca(2+)-dependent molecules play an important role. Calcineurin (CaN) is one such molecule. In this study, we cloned a new isoform of the gene coding for CL strain catalytic subunit CaNA (TcCaNA2) and characterized it molecularly and functionally. There is one copy of the TcCaNA2 gene per haploid genome. It is constitutively transcribed in all T. cruzi developmental forms and is localized predominantly in the cytosol. In the parasite, TcCaNA2 is associated with CaNB. The recombinant protein TcCaNA2 has phosphatase activity that is enhanced by Mn(2+)/Ni(2+). The participation of TcCaNA2 in target cell invasion by metacyclic trypomastigotes was also demonstrated. Metacyclic forms with reduced TcCaNA2 expression following treatment with morpholino antisense oligonucleotides targeted to TcCaNA2 invaded HeLa cells at a lower rate than control parasites treated with morpholino sense oligonucleotides. Similarly, the decreased expression of TcCaNA2 following treatment with antisense morpholino oligonucleotides partially affected the replication of epimastigotes, although to a lesser extent than the decrease in expression following treatment with calcineurin inhibitors. Our findings suggest that the calcineurin activities of TcCaNA2/CaNB and TcCaNA/CaNB, which have distinct cellular localizations (the cytoplasm and the nucleus, respectively), may play a critical role at different stages of T. cruzi development, the former in host cell invasion and the latter in parasite multiplication.

Copper reduces Aß oligomeric species and ameliorates neuromuscular synaptic defects in a C. elegans model of inclusion body myositis.

Alzheimer's disease and inclusion body myositis (IBM) are disorders frequently found in the elderly and characterized by the presence of amyloid-ß peptide (Aß) aggregates. We used Caenorhabditis elegans that express Aß in muscle cells as a model of IBM, with the aim of analyzing Aß-induced muscle pathology and evaluating the consequences of modulating Aß aggregation. First, we tested whether the altered motility we observed in the Aß transgenic strain could be the result of a compromised neuromuscular synapse. Our pharmacological analyses show that synaptic transmission is defective in our model and suggest a specific defect on nicotine-sensitive acetylcholine receptors (AChRs). Through GFP-coupled protein visualization, we found that synaptic dysfunction correlates with mislocalization of ACR-16, the AChR subunit essential for nicotine-triggered currents. Histological and biochemical analysis allowed us to determine that copper treatment increases the amyloid deposits and decreases Aß oligomers in this model. Furthermore, copper treatment improves motility, ACR-16 localization, and synaptic function and delays Aß-induced paralysis. Our results indicate that copper modulates Aß-induced pathology and suggest that Aß oligomers are triggering neuromuscular dysfunction. Our findings emphasize the importance of neuromuscular synaptic dysfunction and the relevance of modulating the amyloidogenic component as an alternative therapeutic approach for this debilitating disease.

Calcineurin B of the human protozoan parasite Trypanosoma cruzi is involved in cell invasion.

During Trypanosoma cruzi cell invasion, signal transduction pathways are triggered in parasite and host cells, leading to a rise in intracellular Ca2+ concentration. We posed the question whether calcineurin (CaN), in particular the functional regulatory subunit CaNB, a Ca2+-binding EF-hand protein, was expressed in T. cruzi and whether it played a role in cell invasion. Here we report the cloning and characterization of CL strain CaNB gene, as well as the participation of CaNB in cell invasion. Treatment of metacyclic trypomastigotes (MT) or tissue-culture trypomastigotes (TCT) with the CaN inhibitors cyclosporin or cypermethrin strongly inhibited (62-64%) their entry into HeLa cells. In assays using anti-phospho-serine/threonine antibodies, a few proteins of MT were found to be dephosphorylated in a manner inhibitable by cyclosporin upon exposure to HeLa cell extract. The phosphatase activity of CaN was detected by a biochemical approach in both MT and TCT. Treatment of parasites with antisense phosphorothioate oligonucleotides directed to TcCaNB-CL, which reduced the expression of TcCaNB and affected TcCaN activity, resulted in approximately 50% inhibition of HeLa cell entry by MT or TCT. Given that TcCaNB-CL may play a key role in cell invasion and differs considerably in its primary structure from the human CaNB, it might be considered as a potential chemotherapeutic target.

Cell invasion by Trypanosoma cruzi amastigotes of distinct infectivities: studies on signaling pathways.

Trypanosoma cruzi metacyclic trypomastigotes of the major phylogenetic lineages use specific signaling pathways to invade host cells. Using a panel of drugs, we studied if the differences in the ability of extracellular amastigotes (EA) from G (T. cruzi I) and CL (T. cruzi II) strains to invade host cells could be associated to activation of specific signaling routes. Sonicated extracts from G or CL strain EA induced transient raises in HeLa cell intracellular Ca(2+) levels in a dose-dependent manner. Treatment of EA with drugs that affect Ca(2+) release from inositol-1,4,5-triphosphate-sensitive stores did not significantly affect the infectivity of either strain, whereas EA of both strains treated with ionomycin plus NH(4)Cl or nigericin that release Ca(2+) from acidocalcisomes had their infectivity reduced. Treatment of parasites with adenylate cyclase activator forskolin increased the infectivity of both strains towards HeLa cells. These data, taken together, suggest that, for host cell invasion, G and CL strain EA engage signaling pathways that lead to an increase of cyclic adenosine monophosphate and Ca(2+) mobilization from acidocalcisomes. Moreover, treatment of EA with genistein reduced by approximately 45% the invasion of HeLa cells by G but not by CL strain, implicating a protein tyrosine kinase in the process. In line with this, HeLa cell extracts contained a protein tyrosine kinase activity that mediated the phosphorylation of 87- and 175-kDa polypeptides of EA from G but not from CL strain. Regarding the target cell response, the activation of host PI3 kinase appears to be required for invasion by either strain as treatment of HeLa cells with wortmannin reduced EA infectivity. These data overall reinforce the concept that cell invasion by T. cruzi EA markedly differs from the process involving metacyclic trypomastigotes.

Trypanosoma cruzi surface molecule gp90 downregulates invasion of gastric mucosal epithelium in orally infected mice.

Experiments were performed to elucidate why Trypanosoma cruzi isolates 573 and 587 differ widely in their efficiency to infect gastric mucosal epithelium when administered orally to mice. These isolates have the same surface profile and a similar capacity to enter host cells in vitro. Metacyclic forms of isolates 573 and 587 and the control CL isolate expressed similar levels of gp82, which is a cell invasion-promoting molecule. Expression of gp90, a molecule that downregulates cell invasion, was lower in the CL isolate. Consistent with this profile, approximately threefold fewer parasites of isolates 573 and 587 entered epithelial HeLa cells, as compared to the CL isolate. No difference in the rate of intracellular parasite replication was observed between isolates. When given orally to mice, metacyclic forms of isolate 573, like the CL isolate, produced high parasitemia (>10(6) parasites per ml at the peak), killing approximately 40% of animals, whereas infection with isolate 587 resulted in low parasitemia (<10(5) parasites per ml), with zero mortality. On the fourth day post-inoculation, tissue sections of the mouse stomach stained with hematoxylin and eosin showed a four to sixfold higher number of epithelial cells infected with isolate 573 or CL than with isolate 587. The rate of intracellular parasite development was similar in all isolates. Mimicking in vivo infection, parasites were treated with pepsin at acidic pH and then assayed for their ability to enter HeLa cells or explanted gastric epithelial cells. Pepsin extensively digested gp90 from isolate 573 and significantly increased invasion of both cells, but had minor effect on gp90 or infectivity of isolates 587 and CL. The profile of g82 digestion was similar in isolates 573 and 587, with partial degradation to a approximately 70 kDa fragment, which preserved the target cell binding domain as well as the region involved in gastric mucin adhesion. Gp82 from CL isolate was resistant to pepsin. Assays with parasites recovered from the mouse stomach 2 h after oral infection showed an extensive digestion of gp90 and increased infectivity of isolate 573, but not of isolate 587 or CL. Our data indicate that T. cruzi infection in vitro does not always correlate with in vivo infection because host factors may act on parasites, modulating their infectivity, as is the case of pepsin digestion of isolate 573 gp90.

Molecular basis of non-virulence of Trypanosoma cruzi clone CL-14.

We investigated the properties of metacyclic trypomastigotes of non-virulent Trypanosoma cruzi clone CL-14, as compared to the parental isolate CL. In contrast to the CL isolate, which produces high parasitemias in mice, metacyclic forms of clone CL-14 failed to produce patent infection. In vitro, the number of clone CL-14 parasites that entered epithelial HeLa cells, after 1 h incubation, was approximately four-fold lower than that of the CL isolate and at 72 h post-infection intracellular replication was not apparent whereas cells infected with the CL isolate contained large number of parasites replicating as amastigotes. CL isolate metacyclic forms were long and slender, with the kinetoplast localised closer to the nucleus than to the posterior end, whereas clone CL-14 parasites were shorter, with the kinetoplast very close to the posterior end. Cysteine proteinase cruzipain and trans-sialidase activities were lower in CL isolate than in clone CL-14. The surface profile was similar, except that the expression of gp82, the stage-specific glycoprotein that promotes CL isolate mucosal infection in vivo and host cell invasion in vitro, was greatly reduced on the surface of clone CL-14 metacyclic forms. Genistein, a specific inhibitor of protein tyrosine kinase, which is activated in CL isolate by binding of gp82 to its host cell receptor, did not affect host cell entry of clone CL-14. In contrast with CL isolate, the infectivity of clone CL-14 was not affected by phospholipase C inhibitor U73122 but was diminished by a combination of ionomycin plus NH(4)Cl, which releases Ca(2+) from acidic vacuoles. Internalisation of clone CL-14, but not of CL isolate, was significantly increased by treating parasites with neuraminidase, which removes sialic acid from the mucin-like surface molecule gp35/50. Taken together, our data suggest an association between the non-virulence of clone CL-14 metacyclic forms and the reduced expression of gp82, which precludes the activation of signal transduction pathways leading to effective host cell invasion.

Infection by Trypanosoma cruzi metacyclic forms deficient in gp82 but expressing a related surface molecule, gp30.

Trypanosoma cruzi metacyclic trypomastigotes invade and replicate in the gastric mucosal epithelium after oral infection. In this study we analyzed the process of infection by T. cruzi isolates deficient in the expression of gp82, the metacyclic stage-specific surface glycoprotein implicated in target cell entry in vitro and in promoting mucosal infection in mice after oral challenge. Mice infected by the oral route with metacyclic forms of gp82-deficient isolate 569 or 588 developed patent parasitemia but at greatly reduced levels compared to those infected with the gp82-expressing isolate CL. Metacyclic forms of both isolates expressed gp30, a surface glycoprotein detectable by monoclonal antibody (MAb) 3F6 directed to gp82. Otherwise, the gp82-deficient isolates displayed a surface profile similar to that of the CL isolate and also entered epithelial HeLa cells in a manner inhibitable by MAb 3F6 and dependent on the parasite signal transduction that involved the activation of protein tyrosine kinase and Ca(2+) mobilization from thapsigargin-sensitive stores. Like gp82, gp30 triggered the host cell Ca(2+) response required for parasite internalization. Purified gp30 and the recombinant gp82 inhibited HeLa cell invasion of metacyclic forms of isolates 569 and 588 by approximately 90 and approximately 70%, respectively. A cell invasion assay performed in the presence of gastric mucin, mimicking the in vivo infection, showed an inhibition of 70 to 75% in the internalization of gp82-deficient isolates but not of the CL isolate. The recombinant gp82 exhibited an adhesive capacity toward gastric mucin much higher than that of gp30. Taken together, our findings indicate that target cell entry of metacyclic trypomastigotes can be mediated either by gp82 or gp30 but that efficient mucosal infection depends on the expression of gp82.

Diterpenoids from Azorella compacta (Umbelliferae) active on Trypanosoma cruzi.

The anti-Trypanosoma cruzi activity of natural products isolated from Azorella compacta was evaluated, with particular emphasis on their effect against intracellular amastigotes. Five diterpenoids from A. compacta derived from mulinane and azorellane were isolated and identified. Only two products, named azorellanol (Y-2) and mulin-11,3-dien-20-oic acid (Y-5), showed trypanocidal activity against all stages of T. cruzi including intracellular amastigotes. At 10 M, these compounds displayed a strong lytic activity. It ranged from 88.4 0.6 to 99.0 1 % for all strains and stages evaluate, with an IC50 /18 h values of 20-84 M and 41-87 M, respectively. The development of intracellular amastigotes was also inhibited by nearly 60% at 25 M. The trypanocidal molecules Y-2 and Y-5 did show different degrees of cytotoxicity depending on the cell line tested, with an IC50 /24 h ranging from 33.2 to 161.2 M. We evaluated the effect of diterpenoids against intracellular T. cruzi forms by immunofluorescent identification of a specific membrane molecular marker (Ssp-4 antigen) of the T. cruzi amastigote forms. The accuracy and reproducibility of the measurements were found to be outstanding when examined by confocal microscopy.

Diterpenoids from Azorella compacta (Umbelliferae) active on Trypanosoma cruzi

The anti-Trypanosoma cruzi activity of natural products isolated from Azorella compacta was evaluated, with particular emphasis on their effect against intracellular amastigotes. Five diterpenoids from A. compacta derived from mulinane and azorellane were isolated and identified. Only two products, named azorellanol (Y-2) and mulin-11,3-dien-20-oic acid (Y-5), showed trypanocidal activity against all stages of T. cruzi including intracellular amastigotes. At 10 æM, these compounds displayed a strong lytic activity. It ranged from 88.4 ± 0.6 to 99.0 ± 1 percent for all strains and stages evaluate, with an IC50 /18 h values of 20-84 æM and 41-87 æM, respectively. The development of intracellular amastigotes was also inhibited by nearly 60 percent at 25 æM. The trypanocidal molecules Y-2 and Y-5 did show different degrees of cytotoxicity depending on the cell line tested, with an IC50 /24 h ranging from 33.2 to 161.2 æM. We evaluated the effect of diterpenoids against intracellular T. cruzi forms by immunofluorescent identification of a specific membrane molecular marker (Ssp-4 antigen) of the T. cruzi amastigote forms. The accuracy and reproducibility of the measurements were found to be outstanding when examined by confocal microscopy

Cell adhesion and Ca2+ signaling activity in stably transfected Trypanosoma cruzi epimastigotes expressing the metacyclic stage-specific surface molecule gp82.

Metacyclic trypomastigotes of Trypanosoma cruzi express a developmentally regulated 82-kDa surface glycoprotein (gp82) that has been implicated in host cell invasion. gp82-mediated interaction of metacyclic forms with target cells induces in both cells activation of the signal transduction pathways, leading to intracellular Ca(2+) mobilization, which is required for parasite internalization. Noninfective epimastigotes do not express detectable levels of gp82 and are unable to induce a Ca(2+) response. We stably transfected epimastigotes with a T. cruzi expression vector carrying the metacyclic stage gp82 cDNA. These transfectants produced a functional gp82, which bound to and triggered a Ca(2+) response in HeLa cells, in the same manner as the metacyclic trypomastigote gp82. Such properties were not found in epimastigotes transfected with the plasmid vector alone. Epimastigotes expressing gp82 on the surface adhered to HeLa cells but were not internalized. Treatment of gp82-expressing epimastigotes with forskolin, an activator of adenylyl cyclase that increases the metacyclic trypomastigote entry into target cells, did not promote parasite internalization. P175, an intracellular tyrosine phosphorylated protein, which appears to play a role in gp82-dependent signaling cascade in metacyclic forms, was undetectable in epimastigotes, either transfected or not with pTEX-gp82. Overall, our results indicate that gp82 is required but not sufficient for target cell invasion.

Involvement of Trypanosoma cruzi metacyclic trypomastigote surface molecule gp82 in adhesion to gastric mucin and invasion of epithelial cells.

Upon oral infection, Trypanosoma cruzi metacyclic trypomastigotes invade and replicate in the gastric mucosal epithelium, being apparently uniquely specialized for adhesion to mucin and mucosal invasion. Here we investigated the involvement of gp82, the metacyclic-stage-specific surface glycoprotein implicated in host cell entry, in both adhesion to gastric mucin and invasion of the mucosal epithelium upon oral challenge. Metacyclic forms, preincubated with a control monoclonal antibody (MAb) or with MAb 3F6 directed to gp82, were administered orally to BALB/c mice, and parasitemia was monitored. Mice that received parasites treated with MAb 3F6 had greatly reduced parasitemia, displaying at the peak a mean number of blood parasites more than 100-fold lower than that of the control group. MAbs directed to other T. cruzi surface glycoproteins had no such effect. gp82, as either a native or a recombinant molecule, but not the metacyclic trypomastigote surface molecule gp90 or gp35/50, bound to gastric mucin in enzyme-linked immunosorbent assays. MAb 3F6 significantly inhibited the penetration of cultured epithelial HeLa cells by metacyclic forms in the absence or in the presence of gastric mucin. Mucin alone did not affect parasite internalization. Parasite infectivity was not altered by treatment of metacyclic forms with pepsin, to which gp82 was resistant, or with proteinase K, which removed the N-terminal portion of gp82 but preserved its host cell binding site. Taken together, these findings suggest that gp82 mediates the interaction of metacyclic trypomastigotes with gastric mucin and the subsequent penetration of underlying epithelial cells.

Activation of distinct signal transduction pathways in Trypanosoma cruzi isolates with differential capacity to invade host cells.

Mammalian cell invasion by Trypanosoma cruzi requires the activation of signal transduction pathways that result in a Ca(2+) response both in the parasite and the host cell. By using drugs that interfere with the signalling processes, we investigated if the difference in the ability of T. cruzi isolates to invade host cells was associated with the activation of distinct signalling routes in the parasites. Experiments were performed with metacyclic trypomastigotes, the developmental forms that initiate infection in the mammalian host, using the highly invasive isolate CL and the poorly infective isolate G, which belong to distinct phylogenetic lineages. Treatment of parasites with adenylyl cyclase activator forskolin increased the infectivity of the G but not of the CL isolate towards HeLa cells. On the other hand, a specific protein tyrosine kinase inhibitor genistein reduced by approximately 75% the penetration of CL but not of G isolate into HeLa cells. In the CL but not in the G isolate, protein tyrosine kinase mediated the phosphorylation of a 175kDa protein in a manner inducible by a HeLa cell extract. Upon treatment with the phospholipase C inhibitor U73122, or with drugs such as caffeine, which affects Ca(2+) release from inositol-1,4,5-triphosphate-sensitive stores, or thapsigargin, an inhibitor of intracellular Ca(2+) transport ATPases, the infectivity of the CL but not of the G isolate diminished significantly (P<0.005). In both isolates, a combination of ionomycin plus NH(4)Cl or nigericin released Ca(2+) from acidic vacuoles containing a Ca(2+)/H(+) exchange system. This treatment reduced the infectivity of metacyclic forms of the G but not of the CL isolate. Taken together, these data suggest that, for host cell invasion, distinct signalling pathways are activated in metacyclic trypomastigotes of the two isolates, leading to Ca(2+) release from different intracellular compartments.

Trichomonosis en adolescentes embarazadas de Antofagasta, Chile / Trichomonosis in pregnant adolescent from Antofagasta, Chile

Los problemas de salud de la adolescencia se caracterizan por una carga psicosocial elevada y un nivel de daño relativamente bajo término de morbilidad y mortalidad, sin embargo, la disminución de la edad promedio de la menarquia y el inicio precoz de actividad sexual coital son factores de riesgo para el embarazo y las enfermedades de transmisión sexual (ETS) entre los adolescentes. En este trabajo se investigó la infección por Trichomonas vaginalis y los factores epidemiológicos y obstétricos relacionados entre 300 adolescentes embarazadas de la ciudad de Antofagasta, cuyas edades variaron entre 12 y 18 años, de las cuales el 87,7 por ciento se concentró en el rango 15 y 17 años, en tanto que el 76,0 por ciento tuvo su menarquia entre los 12-14 años y el 27,3 por ciento inició su actividad sexual antes de los 15 años. Se determinó una tasa de infección por T. vaginalis de un 5,7 por ciento

Actividad de diterpenoides de azorella compacta, llareta, sobre amastigotes de trypanosoma cruzi / Activity of dipernoids isolated from azorella compacta, llareta, on trypanosoma cruzi amastigotes

The trypanocidad activity against amastigote forms of SPA-14, Tulahuen and G strains and CL Brener clone of Trypanosoma cruzi of diterpenoids isolated from Azorella compacta. Phil. (Llareta), a plant with ethnomedicinal prestige from prespanish age, was investigated. Amastigocidal activity was shown in azorellanol (2), diterpene isolated by first time, with an inhitory concentration 50 (IC) that varied between 60 M (CL Brener clone) and 84 M (SPA-14 strain), and in mulin -11,13 -dien-20-oico acid (5) with IC between 41 µM (G strain) and 87 mM (CL Brener clone). The cytotoxicity levels of both compounds against Hela and Vero cells and macrophages J144 are lower than nifurtimox and similar to gentian violet

Estudio epidemiológico de la pediculosis capitis y sarna en escolares básicos de Antofagasta, Chile, 1995 / Epidemiological study of pediculosis capitis and scabies in schoolchildren from Antofagasta, Chile, 1995

In order to contribute to a better knowledge of the pediculosis capitis and scabies during March-December 1995, 1122 primary schoolchildren under 14 years of age in the city-port of Antofagasta in northern Chile (20º South lat.), were examined. A total of 285 (25.4 percent) were found to be infested with Pediculus humanus capitis and only 20 (1.8 percent) with Sarcoptes scabiei. In general the rates of infestation to both ectoparasitic diseases were higher in groups of younger schoolchildren, also higher in women than in men and in those groups with high indexes of crowding and ignorance of the transmission mechanism of pediculosis capitis and scabies